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Re: [PATCH] Add support for /k modfier for matching along with ${^PREMATCH}, ${^MATCH...
[perl5.git] / regcomp.c
index f8052a1..b5faf28 100644 (file)
--- a/regcomp.c
+++ b/regcomp.c
@@ -57,7 +57,7 @@
  ****    Alterations to Henry's code are...
  ****
  ****    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- ****    2000, 2001, 2002, 2003, 2004, 2005, 2006, by Larry Wall and others
+ ****    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 by Larry Wall and others
  ****
  ****    You may distribute under the terms of either the GNU General Public
  ****    License or the Artistic License, as specified in the README file.
 typedef struct RExC_state_t {
     U32                flags;                  /* are we folding, multilining? */
     char       *precomp;               /* uncompiled string. */
-    regexp     *rx;
+    regexp     *rx;                    /* perl core regexp structure */
+    regexp_internal    *rxi;           /* internal data for regexp object pprivate field */        
     char       *start;                 /* Start of input for compile */
     char       *end;                   /* End of input for compile */
     char       *parse;                 /* Input-scan pointer. */
@@ -125,6 +126,7 @@ typedef struct RExC_state_t {
     I32                utf8;
     HV         *charnames;             /* cache of named sequences */
     HV         *paren_names;           /* Paren names */
+    
     regnode    **recurse;              /* Recurse regops */
     I32                recurse_count;          /* Number of recurse regops */
 #if ADD_TO_REGEXEC
@@ -134,19 +136,22 @@ typedef struct RExC_state_t {
 #ifdef DEBUGGING
     const char  *lastparse;
     I32         lastnum;
+    AV          *paren_name_list;       /* idx -> name */
 #define RExC_lastparse (pRExC_state->lastparse)
 #define RExC_lastnum   (pRExC_state->lastnum)
+#define RExC_paren_name_list    (pRExC_state->paren_name_list)
 #endif
 } RExC_state_t;
 
 #define RExC_flags     (pRExC_state->flags)
 #define RExC_precomp   (pRExC_state->precomp)
 #define RExC_rx                (pRExC_state->rx)
+#define RExC_rxi       (pRExC_state->rxi)
 #define RExC_start     (pRExC_state->start)
 #define RExC_end       (pRExC_state->end)
 #define RExC_parse     (pRExC_state->parse)
 #define RExC_whilem_seen       (pRExC_state->whilem_seen)
-#define RExC_offsets   (pRExC_state->rx->offsets) /* I am not like the others */
+#define RExC_offsets   (pRExC_state->rxi->offsets) /* I am not like the others */
 #define RExC_emit      (pRExC_state->emit)
 #define RExC_emit_start        (pRExC_state->emit_start)
 #define RExC_naughty   (pRExC_state->naughty)
@@ -154,7 +159,6 @@ typedef struct RExC_state_t {
 #define RExC_seen      (pRExC_state->seen)
 #define RExC_size      (pRExC_state->size)
 #define RExC_npar      (pRExC_state->npar)
-#define RExC_cpar      (pRExC_state->cpar)
 #define RExC_nestroot   (pRExC_state->nestroot)
 #define RExC_extralen  (pRExC_state->extralen)
 #define RExC_seen_zerolen      (pRExC_state->seen_zerolen)
@@ -168,6 +172,7 @@ typedef struct RExC_state_t {
 #define RExC_recurse   (pRExC_state->recurse)
 #define RExC_recurse_count     (pRExC_state->recurse_count)
 
+
 #define        ISMULT1(c)      ((c) == '*' || (c) == '+' || (c) == '?')
 #define        ISMULT2(s)      ((*s) == '*' || (*s) == '+' || (*s) == '?' || \
        ((*s) == '{' && regcurly(s)))
@@ -342,8 +347,8 @@ static const scan_data_t zero_scan_data =
 #define SCF_SEEN_ACCEPT         0x8000 
 
 #define UTF (RExC_utf8 != 0)
-#define LOC ((RExC_flags & PMf_LOCALE) != 0)
-#define FOLD ((RExC_flags & PMf_FOLD) != 0)
+#define LOC ((RExC_flags & RXf_PMf_LOCALE) != 0)
+#define FOLD ((RExC_flags & RXf_PMf_FOLD) != 0)
 
 #define OOB_UNICODE            12345678
 #define OOB_NAMEDCLASS         -1
@@ -370,7 +375,7 @@ static const scan_data_t zero_scan_data =
  * arg. Show regex, up to a maximum length. If it's too long, chop and add
  * "...".
  */
-#define        FAIL(msg) STMT_START {                                          \
+#define _FAIL(code) STMT_START {                                       \
     const char *ellipses = "";                                         \
     IV len = RExC_end - RExC_precomp;                                  \
                                                                        \
@@ -381,10 +386,17 @@ static const scan_data_t zero_scan_data =
        len = RegexLengthToShowInErrorMessages - 10;                    \
        ellipses = "...";                                               \
     }                                                                  \
-    Perl_croak(aTHX_ "%s in regex m/%.*s%s/",                          \
-           msg, (int)len, RExC_precomp, ellipses);                     \
+    code;                                                               \
 } STMT_END
 
+#define        FAIL(msg) _FAIL(                            \
+    Perl_croak(aTHX_ "%s in regex m/%.*s%s/",      \
+           msg, (int)len, RExC_precomp, ellipses))
+
+#define        FAIL2(msg,arg) _FAIL(                       \
+    Perl_croak(aTHX_ msg " in regex m/%.*s%s/",            \
+           arg, (int)len, RExC_precomp, ellipses))
+
 /*
  * Simple_vFAIL -- like FAIL, but marks the current location in the scan
  */
@@ -548,17 +560,18 @@ static const scan_data_t zero_scan_data =
 #define EXPERIMENTAL_INPLACESCAN
 #endif
 
-#define DEBUG_STUDYDATA(data,depth)                                  \
-DEBUG_OPTIMISE_MORE_r(if(data){                                           \
+#define DEBUG_STUDYDATA(str,data,depth)                              \
+DEBUG_OPTIMISE_MORE_r(if(data){                                      \
     PerlIO_printf(Perl_debug_log,                                    \
-        "%*s"/* Len:%"IVdf"/%"IVdf" */"Pos:%"IVdf"/%"IVdf           \
-        " Flags: %"IVdf" Whilem_c: %"IVdf" Lcp: %"IVdf" ",           \
+        "%*s" str "Pos:%"IVdf"/%"IVdf                                \
+        " Flags: 0x%"UVXf" Whilem_c: %"IVdf" Lcp: %"IVdf" %s",       \
         (int)(depth)*2, "",                                          \
         (IV)((data)->pos_min),                                       \
         (IV)((data)->pos_delta),                                     \
-        (IV)((data)->flags),                                         \
+        (UV)((data)->flags),                                         \
         (IV)((data)->whilem_c),                                      \
-        (IV)((data)->last_closep ? *((data)->last_closep) : -1)      \
+        (IV)((data)->last_closep ? *((data)->last_closep) : -1),     \
+        is_inf ? "INF " : ""                                         \
     );                                                               \
     if ((data)->last_found)                                          \
         PerlIO_printf(Perl_debug_log,                                \
@@ -588,7 +601,7 @@ static void clear_re(pTHX_ void *r);
    floating substrings if needed. */
 
 STATIC void
-S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *minlenp)
+S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *minlenp, int is_inf)
 {
     const STRLEN l = CHR_SVLEN(data->last_found);
     const STRLEN old_l = CHR_SVLEN(*data->longest);
@@ -606,12 +619,12 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *min
            data->minlen_fixed=minlenp; 
            data->lookbehind_fixed=0;
        }
-       else {
+       else { /* *data->longest == data->longest_float */
            data->offset_float_min = l ? data->last_start_min : data->pos_min;
            data->offset_float_max = (l
                                      ? data->last_start_max
                                      : data->pos_min + data->pos_delta);
-           if ((U32)data->offset_float_max > (U32)I32_MAX)
+           if (is_inf || (U32)data->offset_float_max > (U32)I32_MAX)
                data->offset_float_max = I32_MAX;
            if (data->flags & SF_BEFORE_EOL)
                data->flags
@@ -633,7 +646,7 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *min
     }
     data->last_end = -1;
     data->flags &= ~SF_BEFORE_EOL;
-    DEBUG_STUDYDATA(data,0);
+    DEBUG_STUDYDATA("cl_anything: ",data,0);
 }
 
 /* Can match anything (initialization) */
@@ -789,9 +802,9 @@ S_cl_or(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, con
 
 #ifdef DEBUGGING
 /*
-   dump_trie(trie)
-   dump_trie_interim_list(trie,next_alloc)
-   dump_trie_interim_table(trie,next_alloc)
+   dump_trie(trie,widecharmap,revcharmap)
+   dump_trie_interim_list(trie,widecharmap,revcharmap,next_alloc)
+   dump_trie_interim_table(trie,widecharmap,revcharmap,next_alloc)
 
    These routines dump out a trie in a somewhat readable format.
    The _interim_ variants are used for debugging the interim
@@ -804,17 +817,17 @@ S_cl_or(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, con
 */
 
 /*
-  dump_trie(trie)
   Dumps the final compressed table form of the trie to Perl_debug_log.
   Used for debugging make_trie().
 */
  
 STATIC void
-S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
+S_dump_trie(pTHX_ const struct _reg_trie_data *trie, HV *widecharmap,
+           AV *revcharmap, U32 depth)
 {
     U32 state;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
 
 
@@ -823,7 +836,7 @@ S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
         "Match","Base","Ofs" );
 
     for( state = 0 ; state < trie->uniquecharcount ; state++ ) {
-       SV ** const tmp = av_fetch( trie->revcharmap, state, 0);
+       SV ** const tmp = av_fetch( revcharmap, state, 0);
         if ( tmp ) {
             PerlIO_printf( Perl_debug_log, "%*s", 
                 colwidth,
@@ -885,18 +898,19 @@ S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
     }
 }    
 /*
-  dump_trie_interim_list(trie,next_alloc)
   Dumps a fully constructed but uncompressed trie in list form.
   List tries normally only are used for construction when the number of 
   possible chars (trie->uniquecharcount) is very high.
   Used for debugging make_trie().
 */
 STATIC void
-S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc,U32 depth)
+S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie,
+                        HV *widecharmap, AV *revcharmap, U32 next_alloc,
+                        U32 depth)
 {
     U32 state;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
     /* print out the table precompression.  */
     PerlIO_printf( Perl_debug_log, "%*sState :Word | Transition Data\n%*s%s",
@@ -916,7 +930,7 @@ S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc
             );
         }
         for( charid = 1 ; charid <= TRIE_LIST_USED( state ) ; charid++ ) {
-           SV ** const tmp = av_fetch( trie->revcharmap, TRIE_LIST_ITEM(state,charid).forid, 0);
+           SV ** const tmp = av_fetch( revcharmap, TRIE_LIST_ITEM(state,charid).forid, 0);
            if ( tmp ) {
                 PerlIO_printf( Perl_debug_log, "%*s:%3X=%4"UVXf" | ",
                     colwidth,
@@ -938,19 +952,20 @@ S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc
 }    
 
 /*
-  dump_trie_interim_table(trie,next_alloc)
   Dumps a fully constructed but uncompressed trie in table form.
   This is the normal DFA style state transition table, with a few 
   twists to facilitate compression later. 
   Used for debugging make_trie().
 */
 STATIC void
-S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc, U32 depth)
+S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie,
+                         HV *widecharmap, AV *revcharmap, U32 next_alloc,
+                         U32 depth)
 {
     U32 state;
     U16 charid;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
     
     /*
@@ -961,7 +976,7 @@ S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie, U32 next_allo
     PerlIO_printf( Perl_debug_log, "%*sChar : ",(int)depth * 2 + 2,"" );
 
     for( charid = 0 ; charid < trie->uniquecharcount ; charid++ ) {
-       SV ** const tmp = av_fetch( trie->revcharmap, charid, 0);
+       SV ** const tmp = av_fetch( revcharmap, charid, 0);
         if ( tmp ) {
             PerlIO_printf( Perl_debug_log, "%*s", 
                 colwidth,
@@ -1128,7 +1143,7 @@ is the recommended Unicode-aware way of saying
        SV *tmp = newSVpvs("");                                            \
        if (UTF) SvUTF8_on(tmp);                                           \
        Perl_sv_catpvf( aTHX_ tmp, "%c", (int)uvc );                       \
-       av_push( TRIE_REVCHARMAP(trie), tmp );                             \
+       av_push( revcharmap, tmp );                                        \
     } STMT_END
 
 #define TRIE_READ_CHAR STMT_START {                                           \
@@ -1188,14 +1203,14 @@ is the recommended Unicode-aware way of saying
         else                                                    \
             tmp = newSVpvn( "", 0 );                            \
         if ( UTF ) SvUTF8_on( tmp );                            \
-        av_push( trie->words, tmp );                            \
+        av_push( trie_words, tmp );                             \
     });                                                         \
                                                                 \
     curword++;                                                  \
                                                                 \
     if ( noper_next < tail ) {                                  \
         if (!trie->jump)                                        \
-            Newxz( trie->jump, word_count + 1, U16);            \
+            trie->jump = (U16 *) PerlMemShared_calloc( word_count + 1, sizeof(U16) ); \
         trie->jump[curword] = (U16)(noper_next - convert);      \
         if (!jumper)                                            \
             jumper = noper_next;                                \
@@ -1209,7 +1224,8 @@ is the recommended Unicode-aware way of saying
         /* we only allocate the nextword buffer when there    */\
         /* a dupe, so first time we have to do the allocation */\
         if (!trie->nextword)                                    \
-            Newxz( trie->nextword, word_count + 1, U16);        \
+            trie->nextword = (U16 *)                                   \
+               PerlMemShared_calloc( word_count + 1, sizeof(U16));     \
         while ( trie->nextword[dupe] )                          \
             dupe= trie->nextword[dupe];                         \
         trie->nextword[dupe]= curword;                          \
@@ -1239,6 +1255,8 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     dVAR;
     /* first pass, loop through and scan words */
     reg_trie_data *trie;
+    HV *widecharmap = NULL;
+    AV *revcharmap = newAV();
     regnode *cur;
     const U32 uniflags = UTF8_ALLOW_DEFAULT;
     STRLEN len = 0;
@@ -1257,32 +1275,33 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                          )
                      );
 
-    const U32 data_slot = add_data( pRExC_state, 1, "t" );
-    SV *re_trie_maxbuff;
-#ifndef DEBUGGING
-    /* these are only used during construction but are useful during
-     * debugging so we store them in the struct when debugging.
+#ifdef DEBUGGING
+    const U32 data_slot = add_data( pRExC_state, 4, "tuuu" );
+    AV *trie_words = NULL;
+    /* along with revcharmap, this only used during construction but both are
+     * useful during debugging so we store them in the struct when debugging.
      */
+#else
+    const U32 data_slot = add_data( pRExC_state, 2, "tu" );
     STRLEN trie_charcount=0;
-    AV *trie_revcharmap;
 #endif
+    SV *re_trie_maxbuff;
     GET_RE_DEBUG_FLAGS_DECL;
 #ifndef DEBUGGING
     PERL_UNUSED_ARG(depth);
 #endif
 
-    Newxz( trie, 1, reg_trie_data );
+    trie = (reg_trie_data *) PerlMemShared_calloc( 1, sizeof(reg_trie_data) );
     trie->refcount = 1;
     trie->startstate = 1;
     trie->wordcount = word_count;
-    RExC_rx->data->data[ data_slot ] = (void*)trie;
-    Newxz( trie->charmap, 256, U16 );
+    RExC_rxi->data->data[ data_slot ] = (void*)trie;
+    trie->charmap = (U16 *) PerlMemShared_calloc( 256, sizeof(U16) );
     if (!(UTF && folder))
-        Newxz( trie->bitmap, ANYOF_BITMAP_SIZE, char );
+       trie->bitmap = (char *) PerlMemShared_calloc( ANYOF_BITMAP_SIZE, 1 );
     DEBUG_r({
-        trie->words = newAV();
+        trie_words = newAV();
     });
-    TRIE_REVCHARMAP(trie) = newAV();
 
     re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
     if (!SvIOK(re_trie_maxbuff)) {
@@ -1360,10 +1379,10 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                 }
             } else {
                 SV** svpp;
-                if ( !trie->widecharmap )
-                    trie->widecharmap = newHV();
+                if ( !widecharmap )
+                    widecharmap = newHV();
 
-                svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 1 );
+                svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 1 );
 
                 if ( !svpp )
                     Perl_croak( aTHX_ "error creating/fetching widecharmap entry for 0x%"UVXf, uvc );
@@ -1387,11 +1406,11 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     DEBUG_TRIE_COMPILE_r(
         PerlIO_printf( Perl_debug_log, "%*sTRIE(%s): W:%d C:%d Uq:%d Min:%d Max:%d\n",
                 (int)depth * 2 + 2,"",
-                ( trie->widecharmap ? "UTF8" : "NATIVE" ), (int)word_count,
+                ( widecharmap ? "UTF8" : "NATIVE" ), (int)word_count,
                (int)TRIE_CHARCOUNT(trie), trie->uniquecharcount,
                (int)trie->minlen, (int)trie->maxlen )
     );
-    Newxz( trie->wordlen, word_count, U32 );
+    trie->wordlen = (U32 *) PerlMemShared_calloc( word_count, sizeof(U32) );
 
     /*
         We now know what we are dealing with in terms of unique chars and
@@ -1433,8 +1452,10 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
             "%*sCompiling trie using list compiler\n",
             (int)depth * 2 + 2, ""));
-
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+       
+       trie->states = (reg_trie_state *)
+           PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
+                                 sizeof(reg_trie_state) );
         TRIE_LIST_NEW(1);
         next_alloc = 2;
 
@@ -1458,7 +1479,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                     if ( uvc < 256 ) {
                         charid = trie->charmap[ uvc ];
                    } else {
-                        SV** const svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 0);
+                        SV** const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
                         if ( !svpp ) {
                             charid = 0;
                         } else {
@@ -1498,14 +1519,19 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
 
         /* next alloc is the NEXT state to be allocated */
         trie->statecount = next_alloc; 
-        Renew( trie->states, next_alloc, reg_trie_state );
+        trie->states = (reg_trie_state *)
+           PerlMemShared_realloc( trie->states,
+                                  next_alloc
+                                  * sizeof(reg_trie_state) );
 
         /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(
-            dump_trie_interim_list(trie,next_alloc,depth+1)
+        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_list(trie, widecharmap,
+                                                        revcharmap, next_alloc,
+                                                        depth+1)
         );
 
-        Newxz( trie->trans, transcount ,reg_trie_trans );
+        trie->trans = (reg_trie_trans *)
+           PerlMemShared_calloc( transcount, sizeof(reg_trie_trans) );
         {
             U32 state;
             U32 tp = 0;
@@ -1536,7 +1562,10 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                     }
                     if ( transcount < tp + maxid - minid + 1) {
                         transcount *= 2;
-                        Renew( trie->trans, transcount, reg_trie_trans );
+                       trie->trans = (reg_trie_trans *)
+                           PerlMemShared_realloc( trie->trans,
+                                                    transcount
+                                                    * sizeof(reg_trie_trans) );
                         Zero( trie->trans + (transcount / 2), transcount / 2 , reg_trie_trans );
                     }
                     base = trie->uniquecharcount + tp - minid;
@@ -1616,9 +1645,13 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             "%*sCompiling trie using table compiler\n",
             (int)depth * 2 + 2, ""));
 
-        Newxz( trie->trans, ( TRIE_CHARCOUNT(trie) + 1 ) * trie->uniquecharcount + 1,
-              reg_trie_trans );
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+       trie->trans = (reg_trie_trans *)
+           PerlMemShared_calloc( ( TRIE_CHARCOUNT(trie) + 1 )
+                                 * trie->uniquecharcount + 1,
+                                 sizeof(reg_trie_trans) );
+        trie->states = (reg_trie_state *)
+           PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
+                                 sizeof(reg_trie_state) );
         next_alloc = trie->uniquecharcount + 1;
 
 
@@ -1646,7 +1679,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                     if ( uvc < 256 ) {
                         charid = trie->charmap[ uvc ];
                     } else {
-                        SV* const * const svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 0);
+                        SV* const * const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
                         charid = svpp ? (U16)SvIV(*svpp) : 0;
                     }
                     if ( charid ) {
@@ -1669,9 +1702,9 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         } /* end second pass */
 
         /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(
-            dump_trie_interim_table(trie,next_alloc,depth+1)
-        );
+        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_table(trie, widecharmap,
+                                                         revcharmap,
+                                                         next_alloc, depth+1));
 
         {
         /*
@@ -1775,7 +1808,9 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             }
         }
         trie->lasttrans = pos + 1;
-        Renew( trie->states, laststate, reg_trie_state);
+        trie->states = (reg_trie_state *)
+           PerlMemShared_realloc( trie->states, laststate
+                                  * sizeof(reg_trie_state) );
         DEBUG_TRIE_COMPILE_MORE_r(
                 PerlIO_printf( Perl_debug_log,
                    "%*sAlloc: %d Orig: %"IVdf" elements, Final:%"IVdf". Savings of %%%5.2f\n",
@@ -1795,12 +1830,12 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                 (UV)trie->lasttrans)
     );
     /* resize the trans array to remove unused space */
-    Renew( trie->trans, trie->lasttrans, reg_trie_trans);
+    trie->trans = (reg_trie_trans *)
+       PerlMemShared_realloc( trie->trans, trie->lasttrans
+                              * sizeof(reg_trie_trans) );
 
     /* and now dump out the compressed format */
-    DEBUG_TRIE_COMPILE_r(
-        dump_trie(trie,depth+1)
-    );
+    DEBUG_TRIE_COMPILE_r(dump_trie(trie, widecharmap, revcharmap, depth+1));
 
     {   /* Modify the program and insert the new TRIE node*/ 
         U8 nodetype =(U8)(flags & 0xFF);
@@ -1845,7 +1880,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         /* But first we check to see if there is a common prefix we can 
            split out as an EXACT and put in front of the TRIE node.  */
         trie->startstate= 1;
-        if ( trie->bitmap && !trie->widecharmap && !trie->jump  ) {
+        if ( trie->bitmap && !widecharmap && !trie->jump  ) {
             U32 state;
             for ( state = 1 ; state < trie->statecount-1 ; state++ ) {
                 U32 ofs = 0;
@@ -1862,7 +1897,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                          trie->trans[ base + ofs - trie->uniquecharcount ].check == state )
                     {
                         if ( ++count > 1 ) {
-                            SV **tmp = av_fetch( TRIE_REVCHARMAP(trie), ofs, 0);
+                            SV **tmp = av_fetch( revcharmap, ofs, 0);
                            const U8 *ch = (U8*)SvPV_nolen_const( *tmp );
                             if ( state == 1 ) break;
                             if ( count == 2 ) {
@@ -1873,7 +1908,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                                         (int)depth * 2 + 2, "",
                                         (UV)state));
                                if (idx >= 0) {
-                                   SV ** const tmp = av_fetch( TRIE_REVCHARMAP(trie), idx, 0);
+                                   SV ** const tmp = av_fetch( revcharmap, idx, 0);
                                    const U8 * const ch = (U8*)SvPV_nolen_const( *tmp );
 
                                     TRIE_BITMAP_SET(trie,*ch);
@@ -1893,22 +1928,31 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                    }
                 }
                 if ( count == 1 ) {
-                    SV **tmp = av_fetch( TRIE_REVCHARMAP(trie), idx, 0);
-                    const char *ch = SvPV_nolen_const( *tmp );
-                    DEBUG_OPTIMISE_r(
+                    SV **tmp = av_fetch( revcharmap, idx, 0);
+                    char *ch = SvPV_nolen( *tmp );
+                    DEBUG_OPTIMISE_r({
+                        SV *sv=sv_newmortal();
                         PerlIO_printf( Perl_debug_log,
                            "%*sPrefix State: %"UVuf" Idx:%"UVuf" Char='%s'\n",
                             (int)depth * 2 + 2, "",
-                            (UV)state, (UV)idx, ch)
-                    );
+                            (UV)state, (UV)idx, 
+                            pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), 6, 
+                               PL_colors[0], PL_colors[1],
+                               (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
+                               PERL_PV_ESCAPE_FIRSTCHAR 
+                            )
+                        );
+                    });
                     if ( state==1 ) {
                         OP( convert ) = nodetype;
                         str=STRING(convert);
                         STR_LEN(convert)=0;
                     }
-                    *str++=*ch;
-                    STR_LEN(convert)++;
-
+                    while (*ch) {
+                        *str++ = *ch++;
+                        STR_LEN(convert)++;
+                    }
+                    
                } else {
 #ifdef DEBUGGING           
                    if (state>1)
@@ -1925,11 +1969,21 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                 trie->maxlen -= (state - 1);
                 DEBUG_r({
                     regnode *fix = convert;
+                    U32 word = trie->wordcount;
                     mjd_nodelen++;
                     Set_Node_Offset_Length(convert, mjd_offset, state - 1);
                     while( ++fix < n ) {
                         Set_Node_Offset_Length(fix, 0, 0);
                     }
+                    while (word--) {
+                        SV ** const tmp = av_fetch( trie_words, word, 0 );
+                        if (tmp) {
+                            if ( STR_LEN(convert) <= SvCUR(*tmp) )
+                                sv_chop(*tmp, SvPV_nolen(*tmp) + STR_LEN(convert));
+                            else
+                                sv_chop(*tmp, SvPV_nolen(*tmp) + SvCUR(*tmp));
+                        }
+                    }    
                 });
                 if (trie->maxlen) {
                     convert = n;
@@ -1956,7 +2010,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             {
                 OP( convert ) = TRIEC;
                 Copy(trie->bitmap, ((struct regnode_charclass *)convert)->bitmap, ANYOF_BITMAP_SIZE, char);
-                Safefree(trie->bitmap);
+                PerlMemShared_free(trie->bitmap);
                 trie->bitmap= NULL;
             } else 
                 OP( convert ) = TRIE;
@@ -1990,8 +2044,12 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             Set_Node_Offset_Length(convert,mjd_offset,mjd_nodelen);
         });
     } /* end node insert */
-#ifndef DEBUGGING
-    SvREFCNT_dec(TRIE_REVCHARMAP(trie));
+    RExC_rxi->data->data[ data_slot + 1 ] = (void*)widecharmap;
+#ifdef DEBUGGING
+    RExC_rxi->data->data[ data_slot + TRIE_WORDS_OFFSET ] = (void*)trie_words;
+    RExC_rxi->data->data[ data_slot + 3 ] = (void*)revcharmap;
+#else
+    SvREFCNT_dec(revcharmap);
 #endif
     return trie->jump 
            ? MADE_JUMP_TRIE 
@@ -2021,7 +2079,8 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
    try 'g' and succeed, prodceding to match 'cdgu'.
  */
  /* add a fail transition */
-    reg_trie_data *trie=(reg_trie_data *)RExC_rx->data->data[ARG(source)];
+    const U32 trie_offset = ARG(source);
+    reg_trie_data *trie=(reg_trie_data *)RExC_rxi->data->data[trie_offset];
     U32 *q;
     const U32 ucharcount = trie->uniquecharcount;
     const U32 numstates = trie->statecount;
@@ -2040,13 +2099,13 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
 
 
     ARG_SET( stclass, data_slot );
-    Newxz( aho, 1, reg_ac_data );
-    RExC_rx->data->data[ data_slot ] = (void*)aho;
-    aho->trie=trie;
-    aho->states=(reg_trie_state *)savepvn((const char*)trie->states,
-        numstates * sizeof(reg_trie_state));
+    aho = (reg_ac_data *) PerlMemShared_calloc( 1, sizeof(reg_ac_data) );
+    RExC_rxi->data->data[ data_slot ] = (void*)aho;
+    aho->trie=trie_offset;
+    aho->states=(reg_trie_state *)PerlMemShared_malloc( numstates * sizeof(reg_trie_state) );
+    Copy( trie->states, aho->states, numstates, reg_trie_state );
     Newxz( q, numstates, U32);
-    Newxz( aho->fail, numstates, U32 );
+    aho->fail = (U32 *) PerlMemShared_calloc( numstates, sizeof(U32) );
     aho->refcount = 1;
     fail = aho->fail;
     /* initialize fail[0..1] to be 1 so that we always have
@@ -2300,6 +2359,9 @@ typedef struct scan_frame {
     I32 stop; /* what stopparen do we use */
 } scan_frame;
 
+
+#define SCAN_COMMIT(s, data, m) scan_commit(s, data, m, is_inf)
+
 STATIC I32
 S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                         I32 *minlenp, I32 *deltap,
@@ -2328,11 +2390,10 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
     SV *re_trie_maxbuff = NULL;
     regnode *first_non_open = scan;
     I32 stopmin = I32_MAX;
-    scan_frame last_frame= { last, NULL, NULL, stopparen };
-    scan_frame *frame=&last_frame;
-    
+    scan_frame *frame = NULL;
+
     GET_RE_DEBUG_FLAGS_DECL;
-    
+
 #ifdef DEBUGGING
     StructCopy(&zero_scan_data, &data_fake, scan_data_t);
 #endif
@@ -2342,1449 +2403,1474 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
             first_non_open=regnext(first_non_open);
     }
 
-    while (frame) {
-
-       DEBUG_PEEP("FBEG",scan,depth);
-       while ( scan && OP(scan) != END && scan < frame->last ) {
-           /* Peephole optimizer: */
-           DEBUG_STUDYDATA(data,depth);
-           DEBUG_PEEP("Peep",scan,depth);
-           JOIN_EXACT(scan,&min,0);
-
-           /* Follow the next-chain of the current node and optimize
-              away all the NOTHINGs from it.  */
-           if (OP(scan) != CURLYX) {
-               const int max = (reg_off_by_arg[OP(scan)]
-                       ? I32_MAX
-                       /* I32 may be smaller than U16 on CRAYs! */
-                       : (I32_MAX < U16_MAX ? I32_MAX : U16_MAX));
-               int off = (reg_off_by_arg[OP(scan)] ? ARG(scan) : NEXT_OFF(scan));
-               int noff;
-               regnode *n = scan;
-
-               /* Skip NOTHING and LONGJMP. */
-               while ((n = regnext(n))
-                       && ((PL_regkind[OP(n)] == NOTHING && (noff = NEXT_OFF(n)))
-                           || ((OP(n) == LONGJMP) && (noff = ARG(n))))
-                       && off + noff < max)
-                   off += noff;
-               if (reg_off_by_arg[OP(scan)])
-                   ARG(scan) = off;
-               else
-                   NEXT_OFF(scan) = off;
-           }
 
-           /* The principal pseudo-switch.  Cannot be a switch, since we
-              look into several different things.  */
-           if (OP(scan) == BRANCH || OP(scan) == BRANCHJ
-                   || OP(scan) == IFTHEN) {
-               next = regnext(scan);
-               code = OP(scan);
-               /* demq: the op(next)==code check is to see if we have "branch-branch" AFAICT */
-
-               if (OP(next) == code || code == IFTHEN) {
-                   /* NOTE - There is similar code to this block below for handling
-                      TRIE nodes on a re-study.  If you change stuff here check there
-                      too. */
-                   I32 max1 = 0, min1 = I32_MAX, num = 0;
-                   struct regnode_charclass_class accum;
-                   regnode * const startbranch=scan;
-
-                   if (flags & SCF_DO_SUBSTR)
-                       scan_commit(pRExC_state, data, minlenp); /* Cannot merge strings after this. */
-                   if (flags & SCF_DO_STCLASS)
-                       cl_init_zero(pRExC_state, &accum);
+  fake_study_recurse:
+    while ( scan && OP(scan) != END && scan < last ){
+       /* Peephole optimizer: */
+       DEBUG_STUDYDATA("Peep:", data,depth);
+       DEBUG_PEEP("Peep",scan,depth);
+        JOIN_EXACT(scan,&min,0);
+
+       /* Follow the next-chain of the current node and optimize
+          away all the NOTHINGs from it.  */
+       if (OP(scan) != CURLYX) {
+           const int max = (reg_off_by_arg[OP(scan)]
+                      ? I32_MAX
+                      /* I32 may be smaller than U16 on CRAYs! */
+                      : (I32_MAX < U16_MAX ? I32_MAX : U16_MAX));
+           int off = (reg_off_by_arg[OP(scan)] ? ARG(scan) : NEXT_OFF(scan));
+           int noff;
+           regnode *n = scan;
+       
+           /* Skip NOTHING and LONGJMP. */
+           while ((n = regnext(n))
+                  && ((PL_regkind[OP(n)] == NOTHING && (noff = NEXT_OFF(n)))
+                      || ((OP(n) == LONGJMP) && (noff = ARG(n))))
+                  && off + noff < max)
+               off += noff;
+           if (reg_off_by_arg[OP(scan)])
+               ARG(scan) = off;
+           else
+               NEXT_OFF(scan) = off;
+       }
 
-                   while (OP(scan) == code) {
-                       I32 deltanext, minnext, f = 0, fake;
-                       struct regnode_charclass_class this_class;
 
-                       num++;
-                       data_fake.flags = 0;
-                       if (data) {
-                           data_fake.whilem_c = data->whilem_c;
-                           data_fake.last_closep = data->last_closep;
-                       }
-                       else
-                           data_fake.last_closep = &fake;
-                       next = regnext(scan);
+
+       /* The principal pseudo-switch.  Cannot be a switch, since we
+          look into several different things.  */
+       if (OP(scan) == BRANCH || OP(scan) == BRANCHJ
+                  || OP(scan) == IFTHEN) {
+           next = regnext(scan);
+           code = OP(scan);
+           /* demq: the op(next)==code check is to see if we have "branch-branch" AFAICT */
+       
+           if (OP(next) == code || code == IFTHEN) {
+               /* NOTE - There is similar code to this block below for handling
+                  TRIE nodes on a re-study.  If you change stuff here check there
+                  too. */
+               I32 max1 = 0, min1 = I32_MAX, num = 0;
+               struct regnode_charclass_class accum;
+               regnode * const startbranch=scan;
+               
+               if (flags & SCF_DO_SUBSTR)
+                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot merge strings after this. */
+               if (flags & SCF_DO_STCLASS)
+                   cl_init_zero(pRExC_state, &accum);
+
+               while (OP(scan) == code) {
+                   I32 deltanext, minnext, f = 0, fake;
+                   struct regnode_charclass_class this_class;
+
+                   num++;
+                   data_fake.flags = 0;
+                   if (data) {
+                       data_fake.whilem_c = data->whilem_c;
+                       data_fake.last_closep = data->last_closep;
+                   }
+                   else
+                       data_fake.last_closep = &fake;
+
+                   data_fake.pos_delta = delta;
+                   next = regnext(scan);
+                   scan = NEXTOPER(scan);
+                   if (code != BRANCH)
                        scan = NEXTOPER(scan);
-                       if (code != BRANCH)
-                           scan = NEXTOPER(scan);
-                       if (flags & SCF_DO_STCLASS) {
-                           cl_init(pRExC_state, &this_class);
-                           data_fake.start_class = &this_class;
-                           f = SCF_DO_STCLASS_AND;
-                       }
-                       if (flags & SCF_WHILEM_VISITED_POS)
-                           f |= SCF_WHILEM_VISITED_POS;
-
-                       /* we suppose the run is continuous, last=next...*/
-                       minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext,
-                               next, &data_fake,
-                               stopparen, recursed, NULL, f,depth+1);
-                       if (min1 > minnext)
-                           min1 = minnext;
-                       if (max1 < minnext + deltanext)
-                           max1 = minnext + deltanext;
-                       if (deltanext == I32_MAX)
-                           is_inf = is_inf_internal = 1;
-                       scan = next;
-                       if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                           pars++;
-                       if (data_fake.flags & SCF_SEEN_ACCEPT) {
-                           if ( stopmin > minnext)
-                               stopmin = min + min1;
-                           flags &= ~SCF_DO_SUBSTR;
-                           if (data)
-                               data->flags |= SCF_SEEN_ACCEPT;
-                       }
-                       if (data) {
-                           if (data_fake.flags & SF_HAS_EVAL)
-                               data->flags |= SF_HAS_EVAL;
-                           data->whilem_c = data_fake.whilem_c;
-                       }
-                       if (flags & SCF_DO_STCLASS)
-                           cl_or(pRExC_state, &accum, &this_class);
+                   if (flags & SCF_DO_STCLASS) {
+                       cl_init(pRExC_state, &this_class);
+                       data_fake.start_class = &this_class;
+                       f = SCF_DO_STCLASS_AND;
+                   }
+                   if (flags & SCF_WHILEM_VISITED_POS)
+                       f |= SCF_WHILEM_VISITED_POS;
+
+                   /* we suppose the run is continuous, last=next...*/
+                   minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext,
+                                         next, &data_fake,
+                                         stopparen, recursed, NULL, f,depth+1);
+                   if (min1 > minnext)
+                       min1 = minnext;
+                   if (max1 < minnext + deltanext)
+                       max1 = minnext + deltanext;
+                   if (deltanext == I32_MAX)
+                       is_inf = is_inf_internal = 1;
+                   scan = next;
+                   if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
+                       pars++;
+                   if (data_fake.flags & SCF_SEEN_ACCEPT) {
+                       if ( stopmin > minnext) 
+                           stopmin = min + min1;
+                       flags &= ~SCF_DO_SUBSTR;
+                       if (data)
+                           data->flags |= SCF_SEEN_ACCEPT;
+                   }
+                   if (data) {
+                       if (data_fake.flags & SF_HAS_EVAL)
+                           data->flags |= SF_HAS_EVAL;
+                       data->whilem_c = data_fake.whilem_c;
                    }
-                   if (code == IFTHEN && num < 2) /* Empty ELSE branch */
-                       min1 = 0;
-                   if (flags & SCF_DO_SUBSTR) {
-                       data->pos_min += min1;
-                       data->pos_delta += max1 - min1;
-                       if (max1 != min1 || is_inf)
-                           data->longest = &(data->longest_float);
+                   if (flags & SCF_DO_STCLASS)
+                       cl_or(pRExC_state, &accum, &this_class);
+               }
+               if (code == IFTHEN && num < 2) /* Empty ELSE branch */
+                   min1 = 0;
+               if (flags & SCF_DO_SUBSTR) {
+                   data->pos_min += min1;
+                   data->pos_delta += max1 - min1;
+                   if (max1 != min1 || is_inf)
+                       data->longest = &(data->longest_float);
+               }
+               min += min1;
+               delta += max1 - min1;
+               if (flags & SCF_DO_STCLASS_OR) {
+                   cl_or(pRExC_state, data->start_class, &accum);
+                   if (min1) {
+                       cl_and(data->start_class, and_withp);
+                       flags &= ~SCF_DO_STCLASS;
                    }
-                   min += min1;
-                   delta += max1 - min1;
-                   if (flags & SCF_DO_STCLASS_OR) {
-                       cl_or(pRExC_state, data->start_class, &accum);
-                       if (min1) {
-                           cl_and(data->start_class, and_withp);
-                           flags &= ~SCF_DO_STCLASS;
-                       }
+               }
+               else if (flags & SCF_DO_STCLASS_AND) {
+                   if (min1) {
+                       cl_and(data->start_class, &accum);
+                       flags &= ~SCF_DO_STCLASS;
                    }
-                   else if (flags & SCF_DO_STCLASS_AND) {
-                       if (min1) {
-                           cl_and(data->start_class, &accum);
-                           flags &= ~SCF_DO_STCLASS;
-                       }
-                       else {
-                           /* Switch to OR mode: cache the old value of
-                            * data->start_class */
-                           INIT_AND_WITHP;
-                           StructCopy(data->start_class, and_withp,
-                                   struct regnode_charclass_class);
-                           flags &= ~SCF_DO_STCLASS_AND;
-                           StructCopy(&accum, data->start_class,
-                                   struct regnode_charclass_class);
-                           flags |= SCF_DO_STCLASS_OR;
-                           data->start_class->flags |= ANYOF_EOS;
-                       }
+                   else {
+                       /* Switch to OR mode: cache the old value of
+                        * data->start_class */
+                       INIT_AND_WITHP;
+                       StructCopy(data->start_class, and_withp,
+                                  struct regnode_charclass_class);
+                       flags &= ~SCF_DO_STCLASS_AND;
+                       StructCopy(&accum, data->start_class,
+                                  struct regnode_charclass_class);
+                       flags |= SCF_DO_STCLASS_OR;
+                       data->start_class->flags |= ANYOF_EOS;
                    }
+               }
 
-                   if (PERL_ENABLE_TRIE_OPTIMISATION && OP( startbranch ) == BRANCH ) {
-                       /* demq.
-
-                          Assuming this was/is a branch we are dealing with: 'scan' now
-                          points at the item that follows the branch sequence, whatever
-                          it is. We now start at the beginning of the sequence and look
-                          for subsequences of
+                if (PERL_ENABLE_TRIE_OPTIMISATION && OP( startbranch ) == BRANCH ) {
+               /* demq.
 
-                          BRANCH->EXACT=>x1
-                          BRANCH->EXACT=>x2
-                          tail
+                  Assuming this was/is a branch we are dealing with: 'scan' now
+                  points at the item that follows the branch sequence, whatever
+                  it is. We now start at the beginning of the sequence and look
+                  for subsequences of
 
-                          which would be constructed from a pattern like /A|LIST|OF|WORDS/
+                  BRANCH->EXACT=>x1
+                  BRANCH->EXACT=>x2
+                  tail
 
-                          If we can find such a subseqence we need to turn the first
-                          element into a trie and then add the subsequent branch exact
-                          strings to the trie.
+                  which would be constructed from a pattern like /A|LIST|OF|WORDS/
 
-                          We have two cases
+                  If we can find such a subseqence we need to turn the first
+                  element into a trie and then add the subsequent branch exact
+                  strings to the trie.
 
-                          1. patterns where the whole set of branch can be converted. 
+                  We have two cases
 
-                          2. patterns where only a subset can be converted.
+                    1. patterns where the whole set of branch can be converted. 
 
-                          In case 1 we can replace the whole set with a single regop
-                          for the trie. In case 2 we need to keep the start and end
-                          branchs so
+                    2. patterns where only a subset can be converted.
 
-                          'BRANCH EXACT; BRANCH EXACT; BRANCH X'
-                          becomes BRANCH TRIE; BRANCH X;
+                  In case 1 we can replace the whole set with a single regop
+                  for the trie. In case 2 we need to keep the start and end
+                  branchs so
 
-                          There is an additional case, that being where there is a 
-                          common prefix, which gets split out into an EXACT like node
-                          preceding the TRIE node.
+                    'BRANCH EXACT; BRANCH EXACT; BRANCH X'
+                    becomes BRANCH TRIE; BRANCH X;
 
-                          If x(1..n)==tail then we can do a simple trie, if not we make
-                          a "jump" trie, such that when we match the appropriate word
-                          we "jump" to the appopriate tail node. Essentailly we turn
-                          a nested if into a case structure of sorts.
+                 There is an additional case, that being where there is a 
+                 common prefix, which gets split out into an EXACT like node
+                 preceding the TRIE node.
 
-                       */
+                 If x(1..n)==tail then we can do a simple trie, if not we make
+                 a "jump" trie, such that when we match the appropriate word
+                 we "jump" to the appopriate tail node. Essentailly we turn
+                 a nested if into a case structure of sorts.
 
-                       int made=0;
-                       if (!re_trie_maxbuff) {
-                           re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
-                           if (!SvIOK(re_trie_maxbuff))
-                               sv_setiv(re_trie_maxbuff, RE_TRIE_MAXBUF_INIT);
-                       }
-                       if ( SvIV(re_trie_maxbuff)>=0  ) {
-                           regnode *cur;
-                           regnode *first = (regnode *)NULL;
-                           regnode *last = (regnode *)NULL;
-                           regnode *tail = scan;
-                           U8 optype = 0;
-                           U32 count=0;
+               */
+               
+                   int made=0;
+                   if (!re_trie_maxbuff) {
+                       re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
+                       if (!SvIOK(re_trie_maxbuff))
+                           sv_setiv(re_trie_maxbuff, RE_TRIE_MAXBUF_INIT);
+                   }
+                    if ( SvIV(re_trie_maxbuff)>=0  ) {
+                        regnode *cur;
+                        regnode *first = (regnode *)NULL;
+                        regnode *last = (regnode *)NULL;
+                        regnode *tail = scan;
+                        U8 optype = 0;
+                        U32 count=0;
 
 #ifdef DEBUGGING
-                           SV * const mysv = sv_newmortal();       /* for dumping */
+                        SV * const mysv = sv_newmortal();       /* for dumping */
 #endif
-                           /* var tail is used because there may be a TAIL
-                              regop in the way. Ie, the exacts will point to the
-                              thing following the TAIL, but the last branch will
-                              point at the TAIL. So we advance tail. If we
-                              have nested (?:) we may have to move through several
-                              tails.
-                              */
-
-                           while ( OP( tail ) == TAIL ) {
-                               /* this is the TAIL generated by (?:) */
-                               tail = regnext( tail );
-                           }
-
-
-                           DEBUG_OPTIMISE_r({
-                                   regprop(RExC_rx, mysv, tail );
-                                   PerlIO_printf( Perl_debug_log, "%*s%s%s\n",
-                                       (int)depth * 2 + 2, "", 
-                                       "Looking for TRIE'able sequences. Tail node is: ", 
-                                       SvPV_nolen_const( mysv )
-                                       );
-                                   });
-
-                           /*
-
-                              step through the branches, cur represents each
-                              branch, noper is the first thing to be matched
-                              as part of that branch and noper_next is the
-                              regnext() of that node. if noper is an EXACT
-                              and noper_next is the same as scan (our current
-                              position in the regex) then the EXACT branch is
-                              a possible optimization target. Once we have
-                              two or more consequetive such branches we can
-                              create a trie of the EXACT's contents and stich
-                              it in place. If the sequence represents all of
-                              the branches we eliminate the whole thing and
-                              replace it with a single TRIE. If it is a
-                              subsequence then we need to stitch it in. This
-                              means the first branch has to remain, and needs
-                              to be repointed at the item on the branch chain
-                              following the last branch optimized. This could
-                              be either a BRANCH, in which case the
-                              subsequence is internal, or it could be the
-                              item following the branch sequence in which
-                              case the subsequence is at the end.
-
-*/
+                        /* var tail is used because there may be a TAIL
+                           regop in the way. Ie, the exacts will point to the
+                           thing following the TAIL, but the last branch will
+                           point at the TAIL. So we advance tail. If we
+                           have nested (?:) we may have to move through several
+                           tails.
+                         */
+
+                        while ( OP( tail ) == TAIL ) {
+                            /* this is the TAIL generated by (?:) */
+                            tail = regnext( tail );
+                        }
 
-                           /* dont use tail as the end marker for this traverse */
-                           for ( cur = startbranch ; cur != scan ; cur = regnext( cur ) ) {
-                               regnode * const noper = NEXTOPER( cur );
+                        
+                        DEBUG_OPTIMISE_r({
+                            regprop(RExC_rx, mysv, tail );
+                            PerlIO_printf( Perl_debug_log, "%*s%s%s\n",
+                                (int)depth * 2 + 2, "", 
+                                "Looking for TRIE'able sequences. Tail node is: ", 
+                                SvPV_nolen_const( mysv )
+                            );
+                        });
+                        
+                        /*
+
+                           step through the branches, cur represents each
+                           branch, noper is the first thing to be matched
+                           as part of that branch and noper_next is the
+                           regnext() of that node. if noper is an EXACT
+                           and noper_next is the same as scan (our current
+                           position in the regex) then the EXACT branch is
+                           a possible optimization target. Once we have
+                           two or more consequetive such branches we can
+                           create a trie of the EXACT's contents and stich
+                           it in place. If the sequence represents all of
+                           the branches we eliminate the whole thing and
+                           replace it with a single TRIE. If it is a
+                           subsequence then we need to stitch it in. This
+                           means the first branch has to remain, and needs
+                           to be repointed at the item on the branch chain
+                           following the last branch optimized. This could
+                           be either a BRANCH, in which case the
+                           subsequence is internal, or it could be the
+                           item following the branch sequence in which
+                           case the subsequence is at the end.
+
+                        */
+
+                        /* dont use tail as the end marker for this traverse */
+                        for ( cur = startbranch ; cur != scan ; cur = regnext( cur ) ) {
+                            regnode * const noper = NEXTOPER( cur );
 #if defined(DEBUGGING) || defined(NOJUMPTRIE)
-                               regnode * const noper_next = regnext( noper );
+                            regnode * const noper_next = regnext( noper );
 #endif
 
-                               DEBUG_OPTIMISE_r({
-                                   regprop(RExC_rx, mysv, cur);
-                                   PerlIO_printf( Perl_debug_log, "%*s- %s (%d)",
-                                       (int)depth * 2 + 2,"", SvPV_nolen_const( mysv ), REG_NODE_NUM(cur) );
-
-                                   regprop(RExC_rx, mysv, noper);
-                                   PerlIO_printf( Perl_debug_log, " -> %s",
-                                       SvPV_nolen_const(mysv));
-
-                                   if ( noper_next ) {
-                                       regprop(RExC_rx, mysv, noper_next );
-                                       PerlIO_printf( Perl_debug_log,"\t=> %s\t",
-                                           SvPV_nolen_const(mysv));
-                                   }
-                                   PerlIO_printf( Perl_debug_log, "(First==%d,Last==%d,Cur==%d)\n",
-                                       REG_NODE_NUM(first), REG_NODE_NUM(last), REG_NODE_NUM(cur) );
-                               });
-                               if ( (((first && optype!=NOTHING) ? OP( noper ) == optype
-                                               : PL_regkind[ OP( noper ) ] == EXACT )
-                                           || OP(noper) == NOTHING )
+                            DEBUG_OPTIMISE_r({
+                                regprop(RExC_rx, mysv, cur);
+                                PerlIO_printf( Perl_debug_log, "%*s- %s (%d)",
+                                   (int)depth * 2 + 2,"", SvPV_nolen_const( mysv ), REG_NODE_NUM(cur) );
+
+                                regprop(RExC_rx, mysv, noper);
+                                PerlIO_printf( Perl_debug_log, " -> %s",
+                                    SvPV_nolen_const(mysv));
+
+                                if ( noper_next ) {
+                                  regprop(RExC_rx, mysv, noper_next );
+                                  PerlIO_printf( Perl_debug_log,"\t=> %s\t",
+                                    SvPV_nolen_const(mysv));
+                                }
+                                PerlIO_printf( Perl_debug_log, "(First==%d,Last==%d,Cur==%d)\n",
+                                   REG_NODE_NUM(first), REG_NODE_NUM(last), REG_NODE_NUM(cur) );
+                            });
+                            if ( (((first && optype!=NOTHING) ? OP( noper ) == optype
+                                         : PL_regkind[ OP( noper ) ] == EXACT )
+                                  || OP(noper) == NOTHING )
 #ifdef NOJUMPTRIE
-                                       && noper_next == tail
+                                  && noper_next == tail
 #endif
-                                       && count < U16_MAX)
-                               {
-                                   count++;
-                                   if ( !first || optype == NOTHING ) {
-                                       if (!first) first = cur;
-                                       optype = OP( noper );
-                                   } else {
-                                       last = cur;
-                                   }
-                               } else {
-                                   if ( last ) {
-                                       make_trie( pRExC_state,
-                                               startbranch, first, cur, tail, count,
-                                               optype, depth+1 );
-                                   }
-                                   if ( PL_regkind[ OP( noper ) ] == EXACT
+                                  && count < U16_MAX)
+                            {
+                                count++;
+                                if ( !first || optype == NOTHING ) {
+                                    if (!first) first = cur;
+                                    optype = OP( noper );
+                                } else {
+                                    last = cur;
+                                }
+                            } else {
+                                if ( last ) {
+                                    make_trie( pRExC_state, 
+                                            startbranch, first, cur, tail, count, 
+                                            optype, depth+1 );
+                                }
+                                if ( PL_regkind[ OP( noper ) ] == EXACT
 #ifdef NOJUMPTRIE
-                                           && noper_next == tail
+                                     && noper_next == tail
 #endif
-                                       ) {
-                                       count = 1;
-                                       first = cur;
-                                       optype = OP( noper );
-                                   } else {
-                                       count = 0;
-                                       first = NULL;
-                                       optype = 0;
-                                   }
-                                   last = NULL;
-                               }
-                           }
-                           DEBUG_OPTIMISE_r({
-                                   regprop(RExC_rx, mysv, cur);
-                                   PerlIO_printf( Perl_debug_log,
-                                       "%*s- %s (%d) <SCAN FINISHED>\n", (int)depth * 2 + 2,
-                                       "", SvPV_nolen_const( mysv ),REG_NODE_NUM(cur));
-
-                                   });
-                           if ( last ) {
-                               made= make_trie( pRExC_state, startbranch, first, scan, tail, count, optype, depth+1 );
+                                ){
+                                    count = 1;
+                                    first = cur;
+                                    optype = OP( noper );
+                                } else {
+                                    count = 0;
+                                    first = NULL;
+                                    optype = 0;
+                                }
+                                last = NULL;
+                            }
+                        }
+                        DEBUG_OPTIMISE_r({
+                            regprop(RExC_rx, mysv, cur);
+                            PerlIO_printf( Perl_debug_log,
+                              "%*s- %s (%d) <SCAN FINISHED>\n", (int)depth * 2 + 2,
+                              "", SvPV_nolen_const( mysv ),REG_NODE_NUM(cur));
+
+                        });
+                        if ( last ) {
+                            made= make_trie( pRExC_state, startbranch, first, scan, tail, count, optype, depth+1 );
 #ifdef TRIE_STUDY_OPT  
-                               if ( ((made == MADE_EXACT_TRIE &&
-                                               startbranch == first)
-                                           || ( first_non_open == first )) &&
-                                       depth==0 ) {
-                                   flags |= SCF_TRIE_RESTUDY;
-                                   if ( startbranch == first
-                                           && scan == tail )
-                                   {
-                                       RExC_seen &=~REG_TOP_LEVEL_BRANCHES;
-                                   }
-                               }
+                            if ( ((made == MADE_EXACT_TRIE && 
+                                 startbranch == first) 
+                                 || ( first_non_open == first )) && 
+                                 depth==0 ) {
+                                flags |= SCF_TRIE_RESTUDY;
+                                if ( startbranch == first 
+                                     && scan == tail ) 
+                                {
+                                    RExC_seen &=~REG_TOP_LEVEL_BRANCHES;
+                                }
+                            }
 #endif
-                           }
-                       }
-
-                   } /* do trie */
-
-               }
-               else if ( code == BRANCHJ ) {  /* single branch is optimized. */
-                   scan = NEXTOPER(NEXTOPER(scan));
-               } else                  /* single branch is optimized. */
-                   scan = NEXTOPER(scan);
-               continue;
-           } else if (OP(scan) == SUSPEND || OP(scan) == GOSUB || OP(scan) == GOSTART) {
-               scan_frame *newframe = NULL;
-               I32 paren;
-               regnode *start;
-               regnode *end;
-
-               if (OP(scan) != SUSPEND) {
-                   /* set the pointer */
-                   if (OP(scan) == GOSUB) {
-                       paren = ARG(scan);
-                       RExC_recurse[ARG2L(scan)] = scan;
-                       start = RExC_open_parens[paren-1];
-                       end   = RExC_close_parens[paren-1];
-                   } else {
-                       paren = 0;
-                       start = RExC_rx->program + 1;
-                       end   = RExC_opend;
-                   }
-                   if (!recursed) {
-                       Newxz(recursed, (((RExC_npar)>>3) +1), U8);
-                       SAVEFREEPV(recursed);
-                   }
-                   if (!PAREN_TEST(recursed,paren+1)) {
-                       PAREN_SET(recursed,paren+1);
-                       Newx(newframe,1,scan_frame);
-                   } else {
-                       if (flags & SCF_DO_SUBSTR) {
-                           scan_commit(pRExC_state,data,minlenp);
-                           data->longest = &(data->longest_float);
-                       }
-                       is_inf = is_inf_internal = 1;
-                       if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
-                           cl_anything(pRExC_state, data->start_class);
-                       flags &= ~SCF_DO_STCLASS;
-                   }
-               } else {             
-                   Newx(newframe,1,scan_frame);
-                   paren = stopparen;
-                   start = scan+2;
-                   end = regnext(scan);
-               }
-               if (newframe) {
-                   assert(start);
-                   assert(end);
-                   SAVEFREEPV(newframe);
-                   newframe->next = regnext(scan);
-                   newframe->last = end;
-                   newframe->stop = stopparen;
-                   newframe->prev = frame;
-                   frame = newframe;
-                   scan =  start;
-                   stopparen = paren;
-                   continue;
-               } 
+                        }
+                    }
+                    
+                } /* do trie */
+                
            }
-           else if (OP(scan) == EXACT) {
-               I32 l = STR_LEN(scan);
-               UV uc;
-               if (UTF) {
-                   const U8 * const s = (U8*)STRING(scan);
-                   l = utf8_length(s, s + l);
-                   uc = utf8_to_uvchr(s, NULL);
-               } else {
-                   uc = *((U8*)STRING(scan));
+           else if ( code == BRANCHJ ) {  /* single branch is optimized. */
+               scan = NEXTOPER(NEXTOPER(scan));
+           } else                      /* single branch is optimized. */
+               scan = NEXTOPER(scan);
+           continue;
+       } else if (OP(scan) == SUSPEND || OP(scan) == GOSUB || OP(scan) == GOSTART) {
+           scan_frame *newframe = NULL;
+           I32 paren;
+           regnode *start;
+           regnode *end;
+
+           if (OP(scan) != SUSPEND) {
+           /* set the pointer */
+               if (OP(scan) == GOSUB) {
+                   paren = ARG(scan);
+                   RExC_recurse[ARG2L(scan)] = scan;
+                    start = RExC_open_parens[paren-1];
+                    end   = RExC_close_parens[paren-1];
+                } else {
+                    paren = 0;
+                    start = RExC_rxi->program + 1;
+                    end   = RExC_opend;
+                }
+                if (!recursed) {
+                    Newxz(recursed, (((RExC_npar)>>3) +1), U8);
+                    SAVEFREEPV(recursed);
+                }
+                if (!PAREN_TEST(recursed,paren+1)) {
+                   PAREN_SET(recursed,paren+1);
+                    Newx(newframe,1,scan_frame);
+                } else {
+                    if (flags & SCF_DO_SUBSTR) {
+                        SCAN_COMMIT(pRExC_state,data,minlenp);
+                        data->longest = &(data->longest_float);
+                    }
+                    is_inf = is_inf_internal = 1;
+                    if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
+                        cl_anything(pRExC_state, data->start_class);
+                    flags &= ~SCF_DO_STCLASS;
+               }
+            } else {
+               Newx(newframe,1,scan_frame);
+               paren = stopparen;
+               start = scan+2;
+               end = regnext(scan);
+           }
+           if (newframe) {
+                assert(start);
+                assert(end);
+               SAVEFREEPV(newframe);
+               newframe->next = regnext(scan);
+               newframe->last = last;
+               newframe->stop = stopparen;
+               newframe->prev = frame;
+
+               frame = newframe;
+               scan =  start;
+               stopparen = paren;
+               last = end;
+
+               continue;
+           }
+       }
+       else if (OP(scan) == EXACT) {
+           I32 l = STR_LEN(scan);
+           UV uc;
+           if (UTF) {
+               const U8 * const s = (U8*)STRING(scan);
+               l = utf8_length(s, s + l);
+               uc = utf8_to_uvchr(s, NULL);
+           } else {
+               uc = *((U8*)STRING(scan));
+           }
+           min += l;
+           if (flags & SCF_DO_SUBSTR) { /* Update longest substr. */
+               /* The code below prefers earlier match for fixed
+                  offset, later match for variable offset.  */
+               if (data->last_end == -1) { /* Update the start info. */
+                   data->last_start_min = data->pos_min;
+                   data->last_start_max = is_inf
+                       ? I32_MAX : data->pos_min + data->pos_delta;
                }
-               min += l;
-               if (flags & SCF_DO_SUBSTR) { /* Update longest substr. */
-                   /* The code below prefers earlier match for fixed
-                      offset, later match for variable offset.  */
-                   if (data->last_end == -1) { /* Update the start info. */
-                       data->last_start_min = data->pos_min;
-                       data->last_start_max = is_inf
-                           ? I32_MAX : data->pos_min + data->pos_delta;
-                   }
-                   sv_catpvn(data->last_found, STRING(scan), STR_LEN(scan));
-                   if (UTF)
-                       SvUTF8_on(data->last_found);
-                   {
-                       SV * const sv = data->last_found;
-                       MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
-                           mg_find(sv, PERL_MAGIC_utf8) : NULL;
-                       if (mg && mg->mg_len >= 0)
-                           mg->mg_len += utf8_length((U8*)STRING(scan),
-                                   (U8*)STRING(scan)+STR_LEN(scan));
-                   }
-                   data->last_end = data->pos_min + l;
-                   data->pos_min += l; /* As in the first entry. */
-                   data->flags &= ~SF_BEFORE_EOL;
+               sv_catpvn(data->last_found, STRING(scan), STR_LEN(scan));
+               if (UTF)
+                   SvUTF8_on(data->last_found);
+               {
+                   SV * const sv = data->last_found;
+                   MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
+                       mg_find(sv, PERL_MAGIC_utf8) : NULL;
+                   if (mg && mg->mg_len >= 0)
+                       mg->mg_len += utf8_length((U8*)STRING(scan),
+                                                 (U8*)STRING(scan)+STR_LEN(scan));
                }
-               if (flags & SCF_DO_STCLASS_AND) {
-                   /* Check whether it is compatible with what we know already! */
-                   int compat = 1;
-
-                   if (uc >= 0x100 ||
-                           (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
-                            && !ANYOF_BITMAP_TEST(data->start_class, uc)
-                            && (!(data->start_class->flags & ANYOF_FOLD)
-                                || !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
-                      )
-                       compat = 0;
-                   ANYOF_CLASS_ZERO(data->start_class);
-                   ANYOF_BITMAP_ZERO(data->start_class);
-                   if (compat)
-                       ANYOF_BITMAP_SET(data->start_class, uc);
+               data->last_end = data->pos_min + l;
+               data->pos_min += l; /* As in the first entry. */
+               data->flags &= ~SF_BEFORE_EOL;
+           }
+           if (flags & SCF_DO_STCLASS_AND) {
+               /* Check whether it is compatible with what we know already! */
+               int compat = 1;
+
+               if (uc >= 0x100 ||
+                   (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
+                   && !ANYOF_BITMAP_TEST(data->start_class, uc)
+                   && (!(data->start_class->flags & ANYOF_FOLD)
+                       || !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
+                    )
+                   compat = 0;
+               ANYOF_CLASS_ZERO(data->start_class);
+               ANYOF_BITMAP_ZERO(data->start_class);
+               if (compat)
+                   ANYOF_BITMAP_SET(data->start_class, uc);
+               data->start_class->flags &= ~ANYOF_EOS;
+               if (uc < 0x100)
+                 data->start_class->flags &= ~ANYOF_UNICODE_ALL;
+           }
+           else if (flags & SCF_DO_STCLASS_OR) {
+               /* false positive possible if the class is case-folded */
+               if (uc < 0x100)
+                   ANYOF_BITMAP_SET(data->start_class, uc);
+               else
+                   data->start_class->flags |= ANYOF_UNICODE_ALL;
+               data->start_class->flags &= ~ANYOF_EOS;
+               cl_and(data->start_class, and_withp);
+           }
+           flags &= ~SCF_DO_STCLASS;
+       }
+       else if (PL_regkind[OP(scan)] == EXACT) { /* But OP != EXACT! */
+           I32 l = STR_LEN(scan);
+           UV uc = *((U8*)STRING(scan));
+
+           /* Search for fixed substrings supports EXACT only. */
+           if (flags & SCF_DO_SUBSTR) {
+               assert(data);
+               SCAN_COMMIT(pRExC_state, data, minlenp);
+           }
+           if (UTF) {
+               const U8 * const s = (U8 *)STRING(scan);
+               l = utf8_length(s, s + l);
+               uc = utf8_to_uvchr(s, NULL);
+           }
+           min += l;
+           if (flags & SCF_DO_SUBSTR)
+               data->pos_min += l;
+           if (flags & SCF_DO_STCLASS_AND) {
+               /* Check whether it is compatible with what we know already! */
+               int compat = 1;
+
+               if (uc >= 0x100 ||
+                   (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
+                   && !ANYOF_BITMAP_TEST(data->start_class, uc)
+                    && !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
+                   compat = 0;
+               ANYOF_CLASS_ZERO(data->start_class);
+               ANYOF_BITMAP_ZERO(data->start_class);
+               if (compat) {
+                   ANYOF_BITMAP_SET(data->start_class, uc);
                    data->start_class->flags &= ~ANYOF_EOS;
-                   if (uc < 0x100)
-                       data->start_class->flags &= ~ANYOF_UNICODE_ALL;
+                   data->start_class->flags |= ANYOF_FOLD;
+                   if (OP(scan) == EXACTFL)
+                       data->start_class->flags |= ANYOF_LOCALE;
                }
-               else if (flags & SCF_DO_STCLASS_OR) {
-                   /* false positive possible if the class is case-folded */
+           }
+           else if (flags & SCF_DO_STCLASS_OR) {
+               if (data->start_class->flags & ANYOF_FOLD) {
+                   /* false positive possible if the class is case-folded.
+                      Assume that the locale settings are the same... */
                    if (uc < 0x100)
                        ANYOF_BITMAP_SET(data->start_class, uc);
-                   else
-                       data->start_class->flags |= ANYOF_UNICODE_ALL;
                    data->start_class->flags &= ~ANYOF_EOS;
-                   cl_and(data->start_class, and_withp);
                }
-               flags &= ~SCF_DO_STCLASS;
+               cl_and(data->start_class, and_withp);
            }
-           else if (PL_regkind[OP(scan)] == EXACT) { /* But OP != EXACT! */
-               I32 l = STR_LEN(scan);
-               UV uc = *((U8*)STRING(scan));
-
-               /* Search for fixed substrings supports EXACT only. */
+           flags &= ~SCF_DO_STCLASS;
+       }
+       else if (strchr((const char*)PL_varies,OP(scan))) {
+           I32 mincount, maxcount, minnext, deltanext, fl = 0;
+           I32 f = flags, pos_before = 0;
+           regnode * const oscan = scan;
+           struct regnode_charclass_class this_class;
+           struct regnode_charclass_class *oclass = NULL;
+           I32 next_is_eval = 0;
+
+           switch (PL_regkind[OP(scan)]) {
+           case WHILEM:                /* End of (?:...)* . */
+               scan = NEXTOPER(scan);
+               goto finish;
+           case PLUS:
+               if (flags & (SCF_DO_SUBSTR | SCF_DO_STCLASS)) {
+                   next = NEXTOPER(scan);
+                   if (OP(next) == EXACT || (flags & SCF_DO_STCLASS)) {
+                       mincount = 1;
+                       maxcount = REG_INFTY;
+                       next = regnext(scan);
+                       scan = NEXTOPER(scan);
+                       goto do_curly;
+                   }
+               }
+               if (flags & SCF_DO_SUBSTR)
+                   data->pos_min++;
+               min++;
+               /* Fall through. */
+           case STAR:
+               if (flags & SCF_DO_STCLASS) {
+                   mincount = 0;
+                   maxcount = REG_INFTY;
+                   next = regnext(scan);
+                   scan = NEXTOPER(scan);
+                   goto do_curly;
+               }
+               is_inf = is_inf_internal = 1;
+               scan = regnext(scan);
                if (flags & SCF_DO_SUBSTR) {
-                   assert(data);
-                   scan_commit(pRExC_state, data, minlenp);
+                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot extend fixed substrings */
+                   data->longest = &(data->longest_float);
                }
-               if (UTF) {
-                   const U8 * const s = (U8 *)STRING(scan);
-                   l = utf8_length(s, s + l);
-                   uc = utf8_to_uvchr(s, NULL);
+               goto optimize_curly_tail;
+           case CURLY:
+               if (stopparen>0 && (OP(scan)==CURLYN || OP(scan)==CURLYM)
+                   && (scan->flags == stopparen))
+               {
+                   mincount = 1;
+                   maxcount = 1;
+               } else {
+                   mincount = ARG1(scan);
+                   maxcount = ARG2(scan);
                }
-               min += l;
-               if (flags & SCF_DO_SUBSTR)
-                   data->pos_min += l;
-               if (flags & SCF_DO_STCLASS_AND) {
-                   /* Check whether it is compatible with what we know already! */
-                   int compat = 1;
-
-                   if (uc >= 0x100 ||
-                           (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
-                            && !ANYOF_BITMAP_TEST(data->start_class, uc)
-                            && !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
-                       compat = 0;
-                   ANYOF_CLASS_ZERO(data->start_class);
-                   ANYOF_BITMAP_ZERO(data->start_class);
-                   if (compat) {
-                       ANYOF_BITMAP_SET(data->start_class, uc);
-                       data->start_class->flags &= ~ANYOF_EOS;
-                       data->start_class->flags |= ANYOF_FOLD;
-                       if (OP(scan) == EXACTFL)
-                           data->start_class->flags |= ANYOF_LOCALE;
+               next = regnext(scan);
+               if (OP(scan) == CURLYX) {
+                   I32 lp = (data ? *(data->last_closep) : 0);
+                   scan->flags = ((lp <= (I32)U8_MAX) ? (U8)lp : U8_MAX);
+               }
+               scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
+               next_is_eval = (OP(scan) == EVAL);
+             do_curly:
+               if (flags & SCF_DO_SUBSTR) {
+                   if (mincount == 0) SCAN_COMMIT(pRExC_state,data,minlenp); /* Cannot extend fixed substrings */
+                   pos_before = data->pos_min;
+               }
+               if (data) {
+                   fl = data->flags;
+                   data->flags &= ~(SF_HAS_PAR|SF_IN_PAR|SF_HAS_EVAL);
+                   if (is_inf)
+                       data->flags |= SF_IS_INF;
+               }
+               if (flags & SCF_DO_STCLASS) {
+                   cl_init(pRExC_state, &this_class);
+                   oclass = data->start_class;
+                   data->start_class = &this_class;
+                   f |= SCF_DO_STCLASS_AND;
+                   f &= ~SCF_DO_STCLASS_OR;
+               }
+               /* These are the cases when once a subexpression
+                  fails at a particular position, it cannot succeed
+                  even after backtracking at the enclosing scope.
+               
+                  XXXX what if minimal match and we are at the
+                       initial run of {n,m}? */
+               if ((mincount != maxcount - 1) && (maxcount != REG_INFTY))
+                   f &= ~SCF_WHILEM_VISITED_POS;
+
+               /* This will finish on WHILEM, setting scan, or on NULL: */
+               minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext, 
+                                     last, data, stopparen, recursed, NULL,
+                                     (mincount == 0
+                                       ? (f & ~SCF_DO_SUBSTR) : f),depth+1);
+
+               if (flags & SCF_DO_STCLASS)
+                   data->start_class = oclass;
+               if (mincount == 0 || minnext == 0) {
+                   if (flags & SCF_DO_STCLASS_OR) {
+                       cl_or(pRExC_state, data->start_class, &this_class);
+                   }
+                   else if (flags & SCF_DO_STCLASS_AND) {
+                       /* Switch to OR mode: cache the old value of
+                        * data->start_class */
+                       INIT_AND_WITHP;
+                       StructCopy(data->start_class, and_withp,
+                                  struct regnode_charclass_class);
+                       flags &= ~SCF_DO_STCLASS_AND;
+                       StructCopy(&this_class, data->start_class,
+                                  struct regnode_charclass_class);
+                       flags |= SCF_DO_STCLASS_OR;
+                       data->start_class->flags |= ANYOF_EOS;
                    }
+               } else {                /* Non-zero len */
+                   if (flags & SCF_DO_STCLASS_OR) {
+                       cl_or(pRExC_state, data->start_class, &this_class);
+                       cl_and(data->start_class, and_withp);
+                   }
+                   else if (flags & SCF_DO_STCLASS_AND)
+                       cl_and(data->start_class, &this_class);
+                   flags &= ~SCF_DO_STCLASS;
                }
-               else if (flags & SCF_DO_STCLASS_OR) {
-                   if (data->start_class->flags & ANYOF_FOLD) {
-                       /* false positive possible if the class is case-folded.
-                          Assume that the locale settings are the same... */
-                       if (uc < 0x100)
-                           ANYOF_BITMAP_SET(data->start_class, uc);
-                       data->start_class->flags &= ~ANYOF_EOS;
+               if (!scan)              /* It was not CURLYX, but CURLY. */
+                   scan = next;
+               if ( /* ? quantifier ok, except for (?{ ... }) */
+                   (next_is_eval || !(mincount == 0 && maxcount == 1))
+                   && (minnext == 0) && (deltanext == 0)
+                   && data && !(data->flags & (SF_HAS_PAR|SF_IN_PAR))
+                   && maxcount <= REG_INFTY/3 /* Complement check for big count */
+                   && ckWARN(WARN_REGEXP))
+               {
+                   vWARN(RExC_parse,
+                         "Quantifier unexpected on zero-length expression");
+               }
+
+               min += minnext * mincount;
+               is_inf_internal |= ((maxcount == REG_INFTY
+                                    && (minnext + deltanext) > 0)
+                                   || deltanext == I32_MAX);
+               is_inf |= is_inf_internal;
+               delta += (minnext + deltanext) * maxcount - minnext * mincount;
+
+               /* Try powerful optimization CURLYX => CURLYN. */
+               if (  OP(oscan) == CURLYX && data
+                     && data->flags & SF_IN_PAR
+                     && !(data->flags & SF_HAS_EVAL)
+                     && !deltanext && minnext == 1 ) {
+                   /* Try to optimize to CURLYN.  */
+                   regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS;
+                   regnode * const nxt1 = nxt;
+#ifdef DEBUGGING
+                   regnode *nxt2;
+#endif
+
+                   /* Skip open. */
+                   nxt = regnext(nxt);
+                   if (!strchr((const char*)PL_simple,OP(nxt))
+                       && !(PL_regkind[OP(nxt)] == EXACT
+                            && STR_LEN(nxt) == 1))
+                       goto nogo;
+#ifdef DEBUGGING
+                   nxt2 = nxt;
+#endif
+                   nxt = regnext(nxt);
+                   if (OP(nxt) != CLOSE)
+                       goto nogo;
+                   if (RExC_open_parens) {
+                       RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
+                       RExC_close_parens[ARG(nxt1)-1]=nxt+2; /*close->while*/
                    }
-                   cl_and(data->start_class, and_withp);
+                   /* Now we know that nxt2 is the only contents: */
+                   oscan->flags = (U8)ARG(nxt);
+                   OP(oscan) = CURLYN;
+                   OP(nxt1) = NOTHING; /* was OPEN. */
+
+#ifdef DEBUGGING
+                   OP(nxt1 + 1) = OPTIMIZED; /* was count. */
+                   NEXT_OFF(nxt1+ 1) = 0; /* just for consistancy. */
+                   NEXT_OFF(nxt2) = 0; /* just for consistancy with CURLY. */
+                   OP(nxt) = OPTIMIZED;        /* was CLOSE. */
+                   OP(nxt + 1) = OPTIMIZED; /* was count. */
+                   NEXT_OFF(nxt+ 1) = 0; /* just for consistancy. */
+#endif
                }
-               flags &= ~SCF_DO_STCLASS;
-           }
-           else if (strchr((const char*)PL_varies,OP(scan))) {
-               I32 mincount, maxcount, minnext, deltanext, fl = 0;
-               I32 f = flags, pos_before = 0;
-               regnode * const oscan = scan;
-               struct regnode_charclass_class this_class;
-               struct regnode_charclass_class *oclass = NULL;
-               I32 next_is_eval = 0;
+             nogo:
+
+               /* Try optimization CURLYX => CURLYM. */
+               if (  OP(oscan) == CURLYX && data
+                     && !(data->flags & SF_HAS_PAR)
+                     && !(data->flags & SF_HAS_EVAL)
+                     && !deltanext     /* atom is fixed width */
+                     && minnext != 0   /* CURLYM can't handle zero width */
+               ) {
+                   /* XXXX How to optimize if data == 0? */
+                   /* Optimize to a simpler form.  */
+                   regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN */
+                   regnode *nxt2;
+
+                   OP(oscan) = CURLYM;
+                   while ( (nxt2 = regnext(nxt)) /* skip over embedded stuff*/
+                           && (OP(nxt2) != WHILEM))
+                       nxt = nxt2;
+                   OP(nxt2)  = SUCCEED; /* Whas WHILEM */
+                   /* Need to optimize away parenths. */
+                   if (data->flags & SF_IN_PAR) {
+                       /* Set the parenth number.  */
+                       regnode *nxt1 = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN*/
+
+                       if (OP(nxt) != CLOSE)
+                           FAIL("Panic opt close");
+                       oscan->flags = (U8)ARG(nxt);
+                       if (RExC_open_parens) {
+                           RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
+                           RExC_close_parens[ARG(nxt1)-1]=nxt2+1; /*close->NOTHING*/
+                       }
+                       OP(nxt1) = OPTIMIZED;   /* was OPEN. */
+                       OP(nxt) = OPTIMIZED;    /* was CLOSE. */
 
-               switch (PL_regkind[OP(scan)]) {
-                   case WHILEM:                /* End of (?:...)* . */
-                       scan = NEXTOPER(scan);
-                       goto finish;
-                   case PLUS:
-                       if (flags & (SCF_DO_SUBSTR | SCF_DO_STCLASS)) {
-                           next = NEXTOPER(scan);
-                           if (OP(next) == EXACT || (flags & SCF_DO_STCLASS)) {
-                               mincount = 1;
-                               maxcount = REG_INFTY;
-                               next = regnext(scan);
-                               scan = NEXTOPER(scan);
-                               goto do_curly;
+#ifdef DEBUGGING
+                       OP(nxt1 + 1) = OPTIMIZED; /* was count. */
+                       OP(nxt + 1) = OPTIMIZED; /* was count. */
+                       NEXT_OFF(nxt1 + 1) = 0; /* just for consistancy. */
+                       NEXT_OFF(nxt + 1) = 0; /* just for consistancy. */
+#endif
+#if 0
+                       while ( nxt1 && (OP(nxt1) != WHILEM)) {
+                           regnode *nnxt = regnext(nxt1);
+                       
+                           if (nnxt == nxt) {
+                               if (reg_off_by_arg[OP(nxt1)])
+                                   ARG_SET(nxt1, nxt2 - nxt1);
+                               else if (nxt2 - nxt1 < U16_MAX)
+                                   NEXT_OFF(nxt1) = nxt2 - nxt1;
+                               else
+                                   OP(nxt) = NOTHING;  /* Cannot beautify */
                            }
+                           nxt1 = nnxt;
                        }
-                       if (flags & SCF_DO_SUBSTR)
-                           data->pos_min++;
-                       min++;
-                       /* Fall through. */
-                   case STAR:
-                       if (flags & SCF_DO_STCLASS) {
-                           mincount = 0;
-                           maxcount = REG_INFTY;
-                           next = regnext(scan);
-                           scan = NEXTOPER(scan);
-                           goto do_curly;
-                       }
-                       is_inf = is_inf_internal = 1;
-                       scan = regnext(scan);
-                       if (flags & SCF_DO_SUBSTR) {
-                           scan_commit(pRExC_state, data, minlenp); /* Cannot extend fixed substrings */
-                           data->longest = &(data->longest_float);
-                       }
-                       goto optimize_curly_tail;
-                   case CURLY:
-                       if (stopparen>0 && (OP(scan)==CURLYN || OP(scan)==CURLYM)
-                               && (scan->flags == stopparen))
-                       {
-                           mincount = 1;
-                           maxcount = 1;
-                       } else {
-                           mincount = ARG1(scan);
-                           maxcount = ARG2(scan);
-                       }
-                       next = regnext(scan);
-                       if (OP(scan) == CURLYX) {
-                           I32 lp = (data ? *(data->last_closep) : 0);
-                           scan->flags = ((lp <= (I32)U8_MAX) ? (U8)lp : U8_MAX);
-                       }
-                       scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
-                       next_is_eval = (OP(scan) == EVAL);
-do_curly:
-                       if (flags & SCF_DO_SUBSTR) {
-                           if (mincount == 0) scan_commit(pRExC_state,data,minlenp); /* Cannot extend fixed substrings */
-                           pos_before = data->pos_min;
-                       }
-                       if (data) {
-                           fl = data->flags;
-                           data->flags &= ~(SF_HAS_PAR|SF_IN_PAR|SF_HAS_EVAL);
-                           if (is_inf)
-                               data->flags |= SF_IS_INF;
-                       }
-                       if (flags & SCF_DO_STCLASS) {
-                           cl_init(pRExC_state, &this_class);
-                           oclass = data->start_class;
-                           data->start_class = &this_class;
-                           f |= SCF_DO_STCLASS_AND;
-                           f &= ~SCF_DO_STCLASS_OR;
-                       }
-                       /* These are the cases when once a subexpression
-                          fails at a particular position, it cannot succeed
-                          even after backtracking at the enclosing scope.
-
-                          XXXX what if minimal match and we are at the
-                          initial run of {n,m}? */
-                       if ((mincount != maxcount - 1) && (maxcount != REG_INFTY))
-                           f &= ~SCF_WHILEM_VISITED_POS;
-
-                       /* This will finish on WHILEM, setting scan, or on NULL: */
-                       minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext, 
-                               last, data, stopparen, recursed, NULL,
-                               (mincount == 0
-                                ? (f & ~SCF_DO_SUBSTR) : f),depth+1);
-
-                       if (flags & SCF_DO_STCLASS)
-                           data->start_class = oclass;
-                       if (mincount == 0 || minnext == 0) {
-                           if (flags & SCF_DO_STCLASS_OR) {
-                               cl_or(pRExC_state, data->start_class, &this_class);
-                           }
-                           else if (flags & SCF_DO_STCLASS_AND) {
-                               /* Switch to OR mode: cache the old value of
-                                * data->start_class */
-                               INIT_AND_WITHP;
-                               StructCopy(data->start_class, and_withp,
-                                       struct regnode_charclass_class);
-                               flags &= ~SCF_DO_STCLASS_AND;
-                               StructCopy(&this_class, data->start_class,
-                                       struct regnode_charclass_class);
-                               flags |= SCF_DO_STCLASS_OR;
-                               data->start_class->flags |= ANYOF_EOS;
-                           }
-                       } else {                /* Non-zero len */
-                           if (flags & SCF_DO_STCLASS_OR) {
-                               cl_or(pRExC_state, data->start_class, &this_class);
-                               cl_and(data->start_class, and_withp);
-                           }
-                           else if (flags & SCF_DO_STCLASS_AND)
-                               cl_and(data->start_class, &this_class);
-                           flags &= ~SCF_DO_STCLASS;
-                       }
-                       if (!scan)              /* It was not CURLYX, but CURLY. */
-                           scan = next;
-                       if ( /* ? quantifier ok, except for (?{ ... }) */
-                               (next_is_eval || !(mincount == 0 && maxcount == 1))
-                               && (minnext == 0) && (deltanext == 0)
-                               && data && !(data->flags & (SF_HAS_PAR|SF_IN_PAR))
-                               && maxcount <= REG_INFTY/3 /* Complement check for big count */
-                               && ckWARN(WARN_REGEXP))
-                       {
-                           vWARN(RExC_parse,
-                                   "Quantifier unexpected on zero-length expression");
-                       }
-
-                       min += minnext * mincount;
-                       is_inf_internal |= ((maxcount == REG_INFTY
-                                   && (minnext + deltanext) > 0)
-                               || deltanext == I32_MAX);
-                       is_inf |= is_inf_internal;
-                       delta += (minnext + deltanext) * maxcount - minnext * mincount;
-
-                       /* Try powerful optimization CURLYX => CURLYN. */
-                       if (  OP(oscan) == CURLYX && data
-                               && data->flags & SF_IN_PAR
-                               && !(data->flags & SF_HAS_EVAL)
-                               && !deltanext && minnext == 1 ) {
-                           /* Try to optimize to CURLYN.  */
-                           regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS;
-                           regnode * const nxt1 = nxt;
-#ifdef DEBUGGING
-                           regnode *nxt2;
-#endif
-
-                           /* Skip open. */
-                           nxt = regnext(nxt);
-                           if (!strchr((const char*)PL_simple,OP(nxt))
-                                   && !(PL_regkind[OP(nxt)] == EXACT
-                                       && STR_LEN(nxt) == 1))
-                               goto nogo;
-#ifdef DEBUGGING
-                           nxt2 = nxt;
-#endif
-                           nxt = regnext(nxt);
-                           if (OP(nxt) != CLOSE)
-                               goto nogo;
-                           if (RExC_open_parens) {
-                               RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
-                               RExC_close_parens[ARG(nxt1)-1]=nxt+2; /*close->while*/
-                           }
-                           /* Now we know that nxt2 is the only contents: */
-                           oscan->flags = (U8)ARG(nxt);
-                           OP(oscan) = CURLYN;
-                           OP(nxt1) = NOTHING; /* was OPEN. */
-
-#ifdef DEBUGGING
-                           OP(nxt1 + 1) = OPTIMIZED; /* was count. */
-                           NEXT_OFF(nxt1+ 1) = 0; /* just for consistancy. */
-                           NEXT_OFF(nxt2) = 0; /* just for consistancy with CURLY. */
-                           OP(nxt) = OPTIMIZED;        /* was CLOSE. */
-                           OP(nxt + 1) = OPTIMIZED; /* was count. */
-                           NEXT_OFF(nxt+ 1) = 0; /* just for consistancy. */
-#endif
-                       }
-nogo:
-
-                       /* Try optimization CURLYX => CURLYM. */
-                       if (  OP(oscan) == CURLYX && data
-                               && !(data->flags & SF_HAS_PAR)
-                               && !(data->flags & SF_HAS_EVAL)
-                               && !deltanext   /* atom is fixed width */
-                               && minnext != 0 /* CURLYM can't handle zero width */
-                          ) {
-                           /* XXXX How to optimize if data == 0? */
-                           /* Optimize to a simpler form.  */
-                           regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN */
-                           regnode *nxt2;
-
-                           OP(oscan) = CURLYM;
-                           while ( (nxt2 = regnext(nxt)) /* skip over embedded stuff*/
-                                   && (OP(nxt2) != WHILEM))
-                               nxt = nxt2;
-                           OP(nxt2)  = SUCCEED; /* Whas WHILEM */
-                           /* Need to optimize away parenths. */
-                           if (data->flags & SF_IN_PAR) {
-                               /* Set the parenth number.  */
-                               regnode *nxt1 = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN*/
-
-                               if (OP(nxt) != CLOSE)
-                                   FAIL("Panic opt close");
-                               oscan->flags = (U8)ARG(nxt);
-                               if (RExC_open_parens) {
-                                   RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
-                                   RExC_close_parens[ARG(nxt1)-1]=nxt2+1; /*close->NOTHING*/
-                               }
-                               OP(nxt1) = OPTIMIZED;   /* was OPEN. */
-                               OP(nxt) = OPTIMIZED;    /* was CLOSE. */
-
-#ifdef DEBUGGING
-                               OP(nxt1 + 1) = OPTIMIZED; /* was count. */
-                               OP(nxt + 1) = OPTIMIZED; /* was count. */
-                               NEXT_OFF(nxt1 + 1) = 0; /* just for consistancy. */
-                               NEXT_OFF(nxt + 1) = 0; /* just for consistancy. */
-#endif
-#if 0
-                               while ( nxt1 && (OP(nxt1) != WHILEM)) {
-                                   regnode *nnxt = regnext(nxt1);
-
-                                   if (nnxt == nxt) {
-                                       if (reg_off_by_arg[OP(nxt1)])
-                                           ARG_SET(nxt1, nxt2 - nxt1);
-                                       else if (nxt2 - nxt1 < U16_MAX)
-                                           NEXT_OFF(nxt1) = nxt2 - nxt1;
-                                       else
-                                           OP(nxt) = NOTHING;  /* Cannot beautify */
-                                   }
-                                   nxt1 = nnxt;
-                               }
 #endif
-                               /* Optimize again: */
-                               study_chunk(pRExC_state, &nxt1, minlenp, &deltanext, nxt,
-                                       NULL, stopparen, recursed, NULL, 0,depth+1);
-                           }
-                           else
-                               oscan->flags = 0;
-                       }
-                       else if ((OP(oscan) == CURLYX)
-                               && (flags & SCF_WHILEM_VISITED_POS)
-                               /* See the comment on a similar expression above.
-                                  However, this time it not a subexpression
-                                  we care about, but the expression itself. */
-                               && (maxcount == REG_INFTY)
-                               && data && ++data->whilem_c < 16) {
-                           /* This stays as CURLYX, we can put the count/of pair. */
-                           /* Find WHILEM (as in regexec.c) */
-                           regnode *nxt = oscan + NEXT_OFF(oscan);
-
-                           if (OP(PREVOPER(nxt)) == NOTHING) /* LONGJMP */
-                               nxt += ARG(nxt);
-                           PREVOPER(nxt)->flags = (U8)(data->whilem_c
-                                   | (RExC_whilem_seen << 4)); /* On WHILEM */
-                       }
-                       if (data && fl & (SF_HAS_PAR|SF_IN_PAR))
-                           pars++;
-                       if (flags & SCF_DO_SUBSTR) {
-                           SV *last_str = NULL;
-                           int counted = mincount != 0;
+                       /* Optimize again: */
+                       study_chunk(pRExC_state, &nxt1, minlenp, &deltanext, nxt,
+                                   NULL, stopparen, recursed, NULL, 0,depth+1);
+                   }
+                   else
+                       oscan->flags = 0;
+               }
+               else if ((OP(oscan) == CURLYX)
+                        && (flags & SCF_WHILEM_VISITED_POS)
+                        /* See the comment on a similar expression above.
+                           However, this time it not a subexpression
+                           we care about, but the expression itself. */
+                        && (maxcount == REG_INFTY)
+                        && data && ++data->whilem_c < 16) {
+                   /* This stays as CURLYX, we can put the count/of pair. */
+                   /* Find WHILEM (as in regexec.c) */
+                   regnode *nxt = oscan + NEXT_OFF(oscan);
+
+                   if (OP(PREVOPER(nxt)) == NOTHING) /* LONGJMP */
+                       nxt += ARG(nxt);
+                   PREVOPER(nxt)->flags = (U8)(data->whilem_c
+                       | (RExC_whilem_seen << 4)); /* On WHILEM */
+               }
+               if (data && fl & (SF_HAS_PAR|SF_IN_PAR))
+                   pars++;
+               if (flags & SCF_DO_SUBSTR) {
+                   SV *last_str = NULL;
+                   int counted = mincount != 0;
 
-                           if (data->last_end > 0 && mincount != 0) { /* Ends with a string. */
+                   if (data->last_end > 0 && mincount != 0) { /* Ends with a string. */
 #if defined(SPARC64_GCC_WORKAROUND)
-                               I32 b = 0;
-                               STRLEN l = 0;
-                               const char *s = NULL;
-                               I32 old = 0;
+                       I32 b = 0;
+                       STRLEN l = 0;
+                       const char *s = NULL;
+                       I32 old = 0;
 
-                               if (pos_before >= data->last_start_min)
-                                   b = pos_before;
-                               else
-                                   b = data->last_start_min;
+                       if (pos_before >= data->last_start_min)
+                           b = pos_before;
+                       else
+                           b = data->last_start_min;
 
-                               l = 0;
-                               s = SvPV_const(data->last_found, l);
-                               old = b - data->last_start_min;
+                       l = 0;
+                       s = SvPV_const(data->last_found, l);
+                       old = b - data->last_start_min;
 
 #else
-                               I32 b = pos_before >= data->last_start_min
-                                   ? pos_before : data->last_start_min;
-                               STRLEN l;
-                               const char * const s = SvPV_const(data->last_found, l);
-                               I32 old = b - data->last_start_min;
+                       I32 b = pos_before >= data->last_start_min
+                           ? pos_before : data->last_start_min;
+                       STRLEN l;
+                       const char * const s = SvPV_const(data->last_found, l);
+                       I32 old = b - data->last_start_min;
 #endif
 
-                               if (UTF)
-                                   old = utf8_hop((U8*)s, old) - (U8*)s;
-
-                               l -= old;
-                               /* Get the added string: */
-                               last_str = newSVpvn(s  + old, l);
-                               if (UTF)
-                                   SvUTF8_on(last_str);
-                               if (deltanext == 0 && pos_before == b) {
-                                   /* What was added is a constant string */
-                                   if (mincount > 1) {
-                                       SvGROW(last_str, (mincount * l) + 1);
-                                       repeatcpy(SvPVX(last_str) + l,
-                                               SvPVX_const(last_str), l, mincount - 1);
-                                       SvCUR_set(last_str, SvCUR(last_str) * mincount);
-                                       /* Add additional parts. */
-                                       SvCUR_set(data->last_found,
-                                               SvCUR(data->last_found) - l);
-                                       sv_catsv(data->last_found, last_str);
-                                       {
-                                           SV * sv = data->last_found;
-                                           MAGIC *mg =
-                                               SvUTF8(sv) && SvMAGICAL(sv) ?
-                                               mg_find(sv, PERL_MAGIC_utf8) : NULL;
-                                           if (mg && mg->mg_len >= 0)
-                                               mg->mg_len += CHR_SVLEN(last_str);
-                                       }
-                                       data->last_end += l * (mincount - 1);
-                                   }
-                               } else {
-                                   /* start offset must point into the last copy */
-                                   data->last_start_min += minnext * (mincount - 1);
-                                   data->last_start_max += is_inf ? I32_MAX
-                                       : (maxcount - 1) * (minnext + data->pos_delta);
-                               }
-                           }
-                           /* It is counted once already... */
-                           data->pos_min += minnext * (mincount - counted);
-                           data->pos_delta += - counted * deltanext +
-                               (minnext + deltanext) * maxcount - minnext * mincount;
-                           if (mincount != maxcount) {
-                               /* Cannot extend fixed substrings found inside
-                                  the group.  */
-                               scan_commit(pRExC_state,data,minlenp);
-                               if (mincount && last_str) {
-                                   SV * const sv = data->last_found;
-                                   MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
+                       if (UTF)
+                           old = utf8_hop((U8*)s, old) - (U8*)s;
+                       
+                       l -= old;
+                       /* Get the added string: */
+                       last_str = newSVpvn(s  + old, l);
+                       if (UTF)
+                           SvUTF8_on(last_str);
+                       if (deltanext == 0 && pos_before == b) {
+                           /* What was added is a constant string */
+                           if (mincount > 1) {
+                               SvGROW(last_str, (mincount * l) + 1);
+                               repeatcpy(SvPVX(last_str) + l,
+                                         SvPVX_const(last_str), l, mincount - 1);
+                               SvCUR_set(last_str, SvCUR(last_str) * mincount);
+                               /* Add additional parts. */
+                               SvCUR_set(data->last_found,
+                                         SvCUR(data->last_found) - l);
+                               sv_catsv(data->last_found, last_str);
+                               {
+                                   SV * sv = data->last_found;
+                                   MAGIC *mg =
+                                       SvUTF8(sv) && SvMAGICAL(sv) ?
                                        mg_find(sv, PERL_MAGIC_utf8) : NULL;
-
-                                   if (mg)
-                                       mg->mg_len = -1;
-                                   sv_setsv(sv, last_str);
-                                   data->last_end = data->pos_min;
-                                   data->last_start_min =
-                                       data->pos_min - CHR_SVLEN(last_str);
-                                   data->last_start_max = is_inf
-                                       ? I32_MAX
-                                       : data->pos_min + data->pos_delta
-                                       - CHR_SVLEN(last_str);
+                                   if (mg && mg->mg_len >= 0)
+                                       mg->mg_len += CHR_SVLEN(last_str);
                                }
-                               data->longest = &(data->longest_float);
+                               data->last_end += l * (mincount - 1);
                            }
-                           SvREFCNT_dec(last_str);
-                       }
-                       if (data && (fl & SF_HAS_EVAL))
-                           data->flags |= SF_HAS_EVAL;
-optimize_curly_tail:
-                       if (OP(oscan) != CURLYX) {
-                           while (PL_regkind[OP(next = regnext(oscan))] == NOTHING
-                                   && NEXT_OFF(next))
-                               NEXT_OFF(oscan) += NEXT_OFF(next);
+                       } else {
+                           /* start offset must point into the last copy */
+                           data->last_start_min += minnext * (mincount - 1);
+                           data->last_start_max += is_inf ? I32_MAX
+                               : (maxcount - 1) * (minnext + data->pos_delta);
                        }
-                       continue;
-                   default:                    /* REF and CLUMP only? */
-                       if (flags & SCF_DO_SUBSTR) {
-                           scan_commit(pRExC_state,data,minlenp);      /* Cannot expect anything... */
-                           data->longest = &(data->longest_float);
+                   }
+                   /* It is counted once already... */
+                   data->pos_min += minnext * (mincount - counted);
+                   data->pos_delta += - counted * deltanext +
+                       (minnext + deltanext) * maxcount - minnext * mincount;
+                   if (mincount != maxcount) {
+                        /* Cannot extend fixed substrings found inside
+                           the group.  */
+                       SCAN_COMMIT(pRExC_state,data,minlenp);
+                       if (mincount && last_str) {
+                           SV * const sv = data->last_found;
+                           MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
+                               mg_find(sv, PERL_MAGIC_utf8) : NULL;
+
+                           if (mg)
+                               mg->mg_len = -1;
+                           sv_setsv(sv, last_str);
+                           data->last_end = data->pos_min;
+                           data->last_start_min =
+                               data->pos_min - CHR_SVLEN(last_str);
+                           data->last_start_max = is_inf
+                               ? I32_MAX
+                               : data->pos_min + data->pos_delta
+                               - CHR_SVLEN(last_str);
                        }
-                       is_inf = is_inf_internal = 1;
-                       if (flags & SCF_DO_STCLASS_OR)
-                           cl_anything(pRExC_state, data->start_class);
-                       flags &= ~SCF_DO_STCLASS;
-                       break;
+                       data->longest = &(data->longest_float);
+                   }
+                   SvREFCNT_dec(last_str);
                }
-           }
-           else if (strchr((const char*)PL_simple,OP(scan))) {
-               int value = 0;
-
-               if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);
-                   data->pos_min++;
+               if (data && (fl & SF_HAS_EVAL))
+                   data->flags |= SF_HAS_EVAL;
+             optimize_curly_tail:
+               if (OP(oscan) != CURLYX) {
+                   while (PL_regkind[OP(next = regnext(oscan))] == NOTHING
+                          && NEXT_OFF(next))
+                       NEXT_OFF(oscan) += NEXT_OFF(next);
                }
-               min++;
-               if (flags & SCF_DO_STCLASS) {
-                   data->start_class->flags &= ~ANYOF_EOS;     /* No match on empty */
-
-                   /* Some of the logic below assumes that switching
-                      locale on will only add false positives. */
-                   switch (PL_regkind[OP(scan)]) {
-                       case SANY:
-                       default:
-do_default:
-                           /* Perl_croak(aTHX_ "panic: unexpected simple REx opcode %d", OP(scan)); */
-                           if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
-                               cl_anything(pRExC_state, data->start_class);
-                           break;
-                       case REG_ANY:
-                           if (OP(scan) == SANY)
-                               goto do_default;
-                           if (flags & SCF_DO_STCLASS_OR) { /* Everything but \n */
-                               value = (ANYOF_BITMAP_TEST(data->start_class,'\n')
-                                       || (data->start_class->flags & ANYOF_CLASS));
-                               cl_anything(pRExC_state, data->start_class);
-                           }
-                           if (flags & SCF_DO_STCLASS_AND || !value)
-                               ANYOF_BITMAP_CLEAR(data->start_class,'\n');
-                           break;
-                       case ANYOF:
-                           if (flags & SCF_DO_STCLASS_AND)
-                               cl_and(data->start_class,
-                                       (struct regnode_charclass_class*)scan);
-                           else
-                               cl_or(pRExC_state, data->start_class,
-                                       (struct regnode_charclass_class*)scan);
-                           break;
-                       case ALNUM:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
-                                   for (value = 0; value < 256; value++)
-                                       if (!isALNUM(value))
-                                           ANYOF_BITMAP_CLEAR(data->start_class, value);
-                               }
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (isALNUM(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);
-                               }
-                           }
-                           break;
-                       case ALNUML:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
-                           }
-                           else {
-                               ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
-                               data->start_class->flags |= ANYOF_LOCALE;
-                           }
-                           break;
-                       case NALNUM:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
-                                   for (value = 0; value < 256; value++)
-                                       if (isALNUM(value))
-                                           ANYOF_BITMAP_CLEAR(data->start_class, value);
-                               }
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (!isALNUM(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);
-                               }
-                           }
-                           break;
-                       case NALNUML:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
-                           }
-                           else {
-                               data->start_class->flags |= ANYOF_LOCALE;
-                               ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
-                           }
-                           break;
-                       case SPACE:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
-                                   for (value = 0; value < 256; value++)
-                                       if (!isSPACE(value))
-                                           ANYOF_BITMAP_CLEAR(data->start_class, value);
-                               }
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (isSPACE(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);
-                               }
-                           }
-                           break;
-                       case SPACEL:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
-                           }
-                           else {
-                               data->start_class->flags |= ANYOF_LOCALE;
-                               ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
-                           }
-                           break;
-                       case NSPACE:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
-                                   for (value = 0; value < 256; value++)
-                                       if (isSPACE(value))
-                                           ANYOF_BITMAP_CLEAR(data->start_class, value);
-                               }
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (!isSPACE(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);
-                               }
-                           }
-                           break;
-                       case NSPACEL:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               if (data->start_class->flags & ANYOF_LOCALE) {
-                                   ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
-                                   for (value = 0; value < 256; value++)
-                                       if (!isSPACE(value))
-                                           ANYOF_BITMAP_CLEAR(data->start_class, value);
-                               }
-                           }
-                           else {
-                               data->start_class->flags |= ANYOF_LOCALE;
-                               ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
-                           }
-                           break;
-                       case DIGIT:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NDIGIT);
-                               for (value = 0; value < 256; value++)
-                                   if (!isDIGIT(value))
-                                       ANYOF_BITMAP_CLEAR(data->start_class, value);
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_DIGIT);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (isDIGIT(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);                 
-                               }
-                           }
-                           break;
-                       case NDIGIT:
-                           if (flags & SCF_DO_STCLASS_AND) {
-                               ANYOF_CLASS_CLEAR(data->start_class,ANYOF_DIGIT);
-                               for (value = 0; value < 256; value++)
-                                   if (isDIGIT(value))
-                                       ANYOF_BITMAP_CLEAR(data->start_class, value);
-                           }
-                           else {
-                               if (data->start_class->flags & ANYOF_LOCALE)
-                                   ANYOF_CLASS_SET(data->start_class,ANYOF_NDIGIT);
-                               else {
-                                   for (value = 0; value < 256; value++)
-                                       if (!isDIGIT(value))
-                                           ANYOF_BITMAP_SET(data->start_class, value);                 
-                               }
-                           }
-                           break;
-                   }
-                   if (flags & SCF_DO_STCLASS_OR)
-                       cl_and(data->start_class, and_withp);
-                   flags &= ~SCF_DO_STCLASS;
+               continue;
+           default:                    /* REF and CLUMP only? */
+               if (flags & SCF_DO_SUBSTR) {
+                   SCAN_COMMIT(pRExC_state,data,minlenp);      /* Cannot expect anything... */
+                   data->longest = &(data->longest_float);
                }
+               is_inf = is_inf_internal = 1;
+               if (flags & SCF_DO_STCLASS_OR)
+                   cl_anything(pRExC_state, data->start_class);
+               flags &= ~SCF_DO_STCLASS;
+               break;
            }
-           else if (PL_regkind[OP(scan)] == EOL && flags & SCF_DO_SUBSTR) {
-               data->flags |= (OP(scan) == MEOL
-                       ? SF_BEFORE_MEOL
-                       : SF_BEFORE_SEOL);
-           }
-           else if (  PL_regkind[OP(scan)] == BRANCHJ
-                   /* Lookbehind, or need to calculate parens/evals/stclass: */
-                   && (scan->flags || data || (flags & SCF_DO_STCLASS))
-                   && (OP(scan) == IFMATCH || OP(scan) == UNLESSM)) {
-               if ( !PERL_ENABLE_POSITIVE_ASSERTION_STUDY 
-                       || OP(scan) == UNLESSM )
-               {
-                   /* Negative Lookahead/lookbehind
-                      In this case we can't do fixed string optimisation.
-                      */
+       }
+       else if (strchr((const char*)PL_simple,OP(scan))) {
+           int value = 0;
 
-                   I32 deltanext, minnext, fake = 0;
-                   regnode *nscan;
-                   struct regnode_charclass_class intrnl;
-                   int f = 0;
+           if (flags & SCF_DO_SUBSTR) {
+               SCAN_COMMIT(pRExC_state,data,minlenp);
+               data->pos_min++;
+           }
+           min++;
+           if (flags & SCF_DO_STCLASS) {
+               data->start_class->flags &= ~ANYOF_EOS; /* No match on empty */
 
-                   data_fake.flags = 0;
-                   if (data) {
-                       data_fake.whilem_c = data->whilem_c;
-                       data_fake.last_closep = data->last_closep;
+               /* Some of the logic below assumes that switching
+                  locale on will only add false positives. */
+               switch (PL_regkind[OP(scan)]) {
+               case SANY:
+               default:
+                 do_default:
+                   /* Perl_croak(aTHX_ "panic: unexpected simple REx opcode %d", OP(scan)); */
+                   if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
+                       cl_anything(pRExC_state, data->start_class);
+                   break;
+               case REG_ANY:
+                   if (OP(scan) == SANY)
+                       goto do_default;
+                   if (flags & SCF_DO_STCLASS_OR) { /* Everything but \n */
+                       value = (ANYOF_BITMAP_TEST(data->start_class,'\n')
+                                || (data->start_class->flags & ANYOF_CLASS));
+                       cl_anything(pRExC_state, data->start_class);
                    }
+                   if (flags & SCF_DO_STCLASS_AND || !value)
+                       ANYOF_BITMAP_CLEAR(data->start_class,'\n');
+                   break;
+               case ANYOF:
+                   if (flags & SCF_DO_STCLASS_AND)
+                       cl_and(data->start_class,
+                              (struct regnode_charclass_class*)scan);
                    else
-                       data_fake.last_closep = &fake;
-                   if ( flags & SCF_DO_STCLASS && !scan->flags
-                           && OP(scan) == IFMATCH ) { /* Lookahead */
-                       cl_init(pRExC_state, &intrnl);
-                       data_fake.start_class = &intrnl;
-                       f |= SCF_DO_STCLASS_AND;
+                       cl_or(pRExC_state, data->start_class,
+                             (struct regnode_charclass_class*)scan);
+                   break;
+               case ALNUM:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
+                           for (value = 0; value < 256; value++)
+                               if (!isALNUM(value))
+                                   ANYOF_BITMAP_CLEAR(data->start_class, value);
+                       }
                    }
-                   if (flags & SCF_WHILEM_VISITED_POS)
-                       f |= SCF_WHILEM_VISITED_POS;
-                   next = regnext(scan);
-                   nscan = NEXTOPER(NEXTOPER(scan));
-                   minnext = study_chunk(pRExC_state, &nscan, minlenp, &deltanext, 
-                           last, &data_fake, stopparen, recursed, NULL, f, depth+1);
-                   if (scan->flags) {
-                       if (deltanext) {
-                           vFAIL("Variable length lookbehind not implemented");
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (isALNUM(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
                        }
-                       else if (minnext > (I32)U8_MAX) {
-                           vFAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
+                   }
+                   break;
+               case ALNUML:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
+                   }
+                   else {
+                       ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
+                       data->start_class->flags |= ANYOF_LOCALE;
+                   }
+                   break;
+               case NALNUM:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
+                           for (value = 0; value < 256; value++)
+                               if (isALNUM(value))
+                                   ANYOF_BITMAP_CLEAR(data->start_class, value);
                        }
-                       scan->flags = (U8)minnext;
                    }
-                   if (data) {
-                       if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                           pars++;
-                       if (data_fake.flags & SF_HAS_EVAL)
-                           data->flags |= SF_HAS_EVAL;
-                       data->whilem_c = data_fake.whilem_c;
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (!isALNUM(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
+                       }
                    }
-                   if (f & SCF_DO_STCLASS_AND) {
-                       const int was = (data->start_class->flags & ANYOF_EOS);
-
-                       cl_and(data->start_class, &intrnl);
-                       if (was)
-                           data->start_class->flags |= ANYOF_EOS;
+                   break;
+               case NALNUML:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
                    }
-               }
-#if PERL_ENABLE_POSITIVE_ASSERTION_STUDY
-               else {
-                   /* Positive Lookahead/lookbehind
-                      In this case we can do fixed string optimisation,
-                      but we must be careful about it. Note in the case of
-                      lookbehind the positions will be offset by the minimum
-                      length of the pattern, something we won't know about
-                      until after the recurse.
-                      */
-                   I32 deltanext, fake = 0;
-                   regnode *nscan;
-                   struct regnode_charclass_class intrnl;
-                   int f = 0;
-                   /* We use SAVEFREEPV so that when the full compile 
-                      is finished perl will clean up the allocated 
-                      minlens when its all done. This was we don't
-                      have to worry about freeing them when we know
-                      they wont be used, which would be a pain.
-                      */
-                   I32 *minnextp;
-                   Newx( minnextp, 1, I32 );
-                   SAVEFREEPV(minnextp);
-
-                   if (data) {
-                       StructCopy(data, &data_fake, scan_data_t);
-                       if ((flags & SCF_DO_SUBSTR) && data->last_found) {
-                           f |= SCF_DO_SUBSTR;
-                           if (scan->flags) 
-                               scan_commit(pRExC_state, &data_fake,minlenp);
-                           data_fake.last_found=newSVsv(data->last_found);
+                   else {
+                       data->start_class->flags |= ANYOF_LOCALE;
+                       ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
+                   }
+                   break;
+               case SPACE:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
+                           for (value = 0; value < 256; value++)
+                               if (!isSPACE(value))
+                                   ANYOF_BITMAP_CLEAR(data->start_class, value);
                        }
                    }
-                   else
-                       data_fake.last_closep = &fake;
-                   data_fake.flags = 0;
-                   if (is_inf)
-                       data_fake.flags |= SF_IS_INF;
-                   if ( flags & SCF_DO_STCLASS && !scan->flags
-                           && OP(scan) == IFMATCH ) { /* Lookahead */
-                       cl_init(pRExC_state, &intrnl);
-                       data_fake.start_class = &intrnl;
-                       f |= SCF_DO_STCLASS_AND;
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (isSPACE(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
+                       }
                    }
-                   if (flags & SCF_WHILEM_VISITED_POS)
-                       f |= SCF_WHILEM_VISITED_POS;
-                   next = regnext(scan);
-                   nscan = NEXTOPER(NEXTOPER(scan));
-
-                   *minnextp = study_chunk(pRExC_state, &nscan, minnextp, &deltanext, 
-                           last, &data_fake, stopparen, recursed, NULL, f,depth+1);
-                   if (scan->flags) {
-                       if (deltanext) {
-                           vFAIL("Variable length lookbehind not implemented");
+                   break;
+               case SPACEL:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
+                   }
+                   else {
+                       data->start_class->flags |= ANYOF_LOCALE;
+                       ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
+                   }
+                   break;
+               case NSPACE:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
+                           for (value = 0; value < 256; value++)
+                               if (isSPACE(value))
+                                   ANYOF_BITMAP_CLEAR(data->start_class, value);
                        }
-                       else if (*minnextp > (I32)U8_MAX) {
-                           vFAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
+                   }
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (!isSPACE(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
                        }
-                       scan->flags = (U8)*minnextp;
                    }
-
-                   *minnextp += min;
-
-                   if (f & SCF_DO_STCLASS_AND) {
-                       const int was = (data->start_class->flags & ANYOF_EOS);
-
-                       cl_and(data->start_class, &intrnl);
-                       if (was)
-                           data->start_class->flags |= ANYOF_EOS;
+                   break;
+               case NSPACEL:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       if (data->start_class->flags & ANYOF_LOCALE) {
+                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
+                           for (value = 0; value < 256; value++)
+                               if (!isSPACE(value))
+                                   ANYOF_BITMAP_CLEAR(data->start_class, value);
+                       }
                    }
-                   if (data) {
-                       if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                           pars++;
-                       if (data_fake.flags & SF_HAS_EVAL)
-                           data->flags |= SF_HAS_EVAL;
-                       data->whilem_c = data_fake.whilem_c;
-                       if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) {
-                           if (RExC_rx->minlen<*minnextp)
-                               RExC_rx->minlen=*minnextp;
-                           scan_commit(pRExC_state, &data_fake, minnextp);
-                           SvREFCNT_dec(data_fake.last_found);
-
-                           if ( data_fake.minlen_fixed != minlenp ) 
-                           {
-                               data->offset_fixed= data_fake.offset_fixed;
-                               data->minlen_fixed= data_fake.minlen_fixed;
-                               data->lookbehind_fixed+= scan->flags;
-                           }
-                           if ( data_fake.minlen_float != minlenp )
-                           {
-                               data->minlen_float= data_fake.minlen_float;
-                               data->offset_float_min=data_fake.offset_float_min;
-                               data->offset_float_max=data_fake.offset_float_max;
-                               data->lookbehind_float+= scan->flags;
-                           }
+                   else {
+                       data->start_class->flags |= ANYOF_LOCALE;
+                       ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
+                   }
+                   break;
+               case DIGIT:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NDIGIT);
+                       for (value = 0; value < 256; value++)
+                           if (!isDIGIT(value))
+                               ANYOF_BITMAP_CLEAR(data->start_class, value);
+                   }
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_DIGIT);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (isDIGIT(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
+                       }
+                   }
+                   break;
+               case NDIGIT:
+                   if (flags & SCF_DO_STCLASS_AND) {
+                       ANYOF_CLASS_CLEAR(data->start_class,ANYOF_DIGIT);
+                       for (value = 0; value < 256; value++)
+                           if (isDIGIT(value))
+                               ANYOF_BITMAP_CLEAR(data->start_class, value);
+                   }
+                   else {
+                       if (data->start_class->flags & ANYOF_LOCALE)
+                           ANYOF_CLASS_SET(data->start_class,ANYOF_NDIGIT);
+                       else {
+                           for (value = 0; value < 256; value++)
+                               if (!isDIGIT(value))
+                                   ANYOF_BITMAP_SET(data->start_class, value);                 
                        }
                    }
+                   break;
+               }
+               if (flags & SCF_DO_STCLASS_OR)
+                   cl_and(data->start_class, and_withp);
+               flags &= ~SCF_DO_STCLASS;
+           }
+       }
+       else if (PL_regkind[OP(scan)] == EOL && flags & SCF_DO_SUBSTR) {
+           data->flags |= (OP(scan) == MEOL
+                           ? SF_BEFORE_MEOL
+                           : SF_BEFORE_SEOL);
+       }
+       else if (  PL_regkind[OP(scan)] == BRANCHJ
+                /* Lookbehind, or need to calculate parens/evals/stclass: */
+                  && (scan->flags || data || (flags & SCF_DO_STCLASS))
+                  && (OP(scan) == IFMATCH || OP(scan) == UNLESSM)) {
+            if ( !PERL_ENABLE_POSITIVE_ASSERTION_STUDY 
+                || OP(scan) == UNLESSM )
+            {
+                /* Negative Lookahead/lookbehind
+                   In this case we can't do fixed string optimisation.
+                */
 
+                I32 deltanext, minnext, fake = 0;
+                regnode *nscan;
+                struct regnode_charclass_class intrnl;
+                int f = 0;
 
+                data_fake.flags = 0;
+                if (data) {
+                    data_fake.whilem_c = data->whilem_c;
+                    data_fake.last_closep = data->last_closep;
                }
-#endif
+                else
+                    data_fake.last_closep = &fake;
+               data_fake.pos_delta = delta;
+                if ( flags & SCF_DO_STCLASS && !scan->flags
+                     && OP(scan) == IFMATCH ) { /* Lookahead */
+                    cl_init(pRExC_state, &intrnl);
+                    data_fake.start_class = &intrnl;
+                    f |= SCF_DO_STCLASS_AND;
+               }
+                if (flags & SCF_WHILEM_VISITED_POS)
+                    f |= SCF_WHILEM_VISITED_POS;
+                next = regnext(scan);
+                nscan = NEXTOPER(NEXTOPER(scan));
+                minnext = study_chunk(pRExC_state, &nscan, minlenp, &deltanext, 
+                    last, &data_fake, stopparen, recursed, NULL, f, depth+1);
+                if (scan->flags) {
+                    if (deltanext) {
+                       FAIL("Variable length lookbehind not implemented");
+                    }
+                    else if (minnext > (I32)U8_MAX) {
+                       FAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
+                    }
+                    scan->flags = (U8)minnext;
+                }
+                if (data) {
+                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
+                        pars++;
+                    if (data_fake.flags & SF_HAS_EVAL)
+                        data->flags |= SF_HAS_EVAL;
+                    data->whilem_c = data_fake.whilem_c;
+                }
+                if (f & SCF_DO_STCLASS_AND) {
+                    const int was = (data->start_class->flags & ANYOF_EOS);
+
+                    cl_and(data->start_class, &intrnl);
+                    if (was)
+                        data->start_class->flags |= ANYOF_EOS;
+                }
            }
-           else if (OP(scan) == OPEN) {
-               if (stopparen != (I32)ARG(scan))
-                   pars++;
+#if PERL_ENABLE_POSITIVE_ASSERTION_STUDY
+            else {
+                /* Positive Lookahead/lookbehind
+                   In this case we can do fixed string optimisation,
+                   but we must be careful about it. Note in the case of
+                   lookbehind the positions will be offset by the minimum
+                   length of the pattern, something we won't know about
+                   until after the recurse.
+                */
+                I32 deltanext, fake = 0;
+                regnode *nscan;
+                struct regnode_charclass_class intrnl;
+                int f = 0;
+                /* We use SAVEFREEPV so that when the full compile 
+                    is finished perl will clean up the allocated 
+                    minlens when its all done. This was we don't
+                    have to worry about freeing them when we know
+                    they wont be used, which would be a pain.
+                 */
+                I32 *minnextp;
+                Newx( minnextp, 1, I32 );
+                SAVEFREEPV(minnextp);
+
+                if (data) {
+                    StructCopy(data, &data_fake, scan_data_t);
+                    if ((flags & SCF_DO_SUBSTR) && data->last_found) {
+                        f |= SCF_DO_SUBSTR;
+                        if (scan->flags) 
+                            SCAN_COMMIT(pRExC_state, &data_fake,minlenp);
+                        data_fake.last_found=newSVsv(data->last_found);
+                    }
+                }
+                else
+                    data_fake.last_closep = &fake;
+                data_fake.flags = 0;
+               data_fake.pos_delta = delta;
+                if (is_inf)
+                   data_fake.flags |= SF_IS_INF;
+                if ( flags & SCF_DO_STCLASS && !scan->flags
+                     && OP(scan) == IFMATCH ) { /* Lookahead */
+                    cl_init(pRExC_state, &intrnl);
+                    data_fake.start_class = &intrnl;
+                    f |= SCF_DO_STCLASS_AND;
+                }
+                if (flags & SCF_WHILEM_VISITED_POS)
+                    f |= SCF_WHILEM_VISITED_POS;
+                next = regnext(scan);
+                nscan = NEXTOPER(NEXTOPER(scan));
+
+                *minnextp = study_chunk(pRExC_state, &nscan, minnextp, &deltanext, 
+                    last, &data_fake, stopparen, recursed, NULL, f,depth+1);
+                if (scan->flags) {
+                    if (deltanext) {
+                       FAIL("Variable length lookbehind not implemented");
+                    }
+                    else if (*minnextp > (I32)U8_MAX) {
+                       FAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
+                    }
+                    scan->flags = (U8)*minnextp;
+                }
+
+                *minnextp += min;
+
+                if (f & SCF_DO_STCLASS_AND) {
+                    const int was = (data->start_class->flags & ANYOF_EOS);
+
+                    cl_and(data->start_class, &intrnl);
+                    if (was)
+                        data->start_class->flags |= ANYOF_EOS;
+                }
+                if (data) {
+                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
+                        pars++;
+                    if (data_fake.flags & SF_HAS_EVAL)
+                        data->flags |= SF_HAS_EVAL;
+                    data->whilem_c = data_fake.whilem_c;
+                    if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) {
+                        if (RExC_rx->minlen<*minnextp)
+                            RExC_rx->minlen=*minnextp;
+                        SCAN_COMMIT(pRExC_state, &data_fake, minnextp);
+                        SvREFCNT_dec(data_fake.last_found);
+                        
+                        if ( data_fake.minlen_fixed != minlenp ) 
+                        {
+                            data->offset_fixed= data_fake.offset_fixed;
+                            data->minlen_fixed= data_fake.minlen_fixed;
+                            data->lookbehind_fixed+= scan->flags;
+                        }
+                        if ( data_fake.minlen_float != minlenp )
+                        {
+                            data->minlen_float= data_fake.minlen_float;
+                            data->offset_float_min=data_fake.offset_float_min;
+                            data->offset_float_max=data_fake.offset_float_max;
+                            data->lookbehind_float+= scan->flags;
+                        }
+                    }
+                }
+
+
            }
-           else if (OP(scan) == CLOSE) {
-               if (stopparen == (I32)ARG(scan)) {
-                   break;
-               }
-               if ((I32)ARG(scan) == is_par) {
-                   next = regnext(scan);
+#endif
+       }
+       else if (OP(scan) == OPEN) {
+           if (stopparen != (I32)ARG(scan))
+               pars++;
+       }
+       else if (OP(scan) == CLOSE) {
+           if (stopparen == (I32)ARG(scan)) {
+               break;
+           }
+           if ((I32)ARG(scan) == is_par) {
+               next = regnext(scan);
 
-                   if ( next && (OP(next) != WHILEM) && next < last)
-                       is_par = 0;             /* Disable optimization */
-               }
-               if (data)
-                   *(data->last_closep) = ARG(scan);
+               if ( next && (OP(next) != WHILEM) && next < last)
+                   is_par = 0;         /* Disable optimization */
            }
-           else if (OP(scan) == EVAL) {
+           if (data)
+               *(data->last_closep) = ARG(scan);
+       }
+       else if (OP(scan) == EVAL) {
                if (data)
                    data->flags |= SF_HAS_EVAL;
+       }
+       else if ( PL_regkind[OP(scan)] == ENDLIKE ) {
+           if (flags & SCF_DO_SUBSTR) {
+               SCAN_COMMIT(pRExC_state,data,minlenp);
+               flags &= ~SCF_DO_SUBSTR;
            }
-           else if ( PL_regkind[OP(scan)] == ENDLIKE ) {
-               if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);
-                   flags &= ~SCF_DO_SUBSTR;
-               }
-               if (data && OP(scan)==ACCEPT) {
-                   data->flags |= SCF_SEEN_ACCEPT;
-                   if (stopmin > min)
-                       stopmin = min;
-               }
+           if (data && OP(scan)==ACCEPT) {
+               data->flags |= SCF_SEEN_ACCEPT;
+               if (stopmin > min)
+                   stopmin = min;
            }
-           else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */
-           {
+       }
+       else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */
+       {
                if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);
+                   SCAN_COMMIT(pRExC_state,data,minlenp);
                    data->longest = &(data->longest_float);
                }
                is_inf = is_inf_internal = 1;
                if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
                    cl_anything(pRExC_state, data->start_class);
                flags &= ~SCF_DO_STCLASS;
-           }
+       }
+       else if (OP(scan) == GPOS) {
+           if (!(RExC_rx->extflags & RXf_GPOS_FLOAT) &&
+               !(delta || is_inf || (data && data->pos_delta))) 
+           {
+               if (!(RExC_rx->extflags & RXf_ANCH) && (flags & SCF_DO_SUBSTR))
+                   RExC_rx->extflags |= RXf_ANCH_GPOS;
+               if (RExC_rx->gofs < (U32)min)
+                   RExC_rx->gofs = min;
+            } else {
+                RExC_rx->extflags |= RXf_GPOS_FLOAT;
+                RExC_rx->gofs = 0;
+            }      
+       }
 #ifdef TRIE_STUDY_OPT
 #ifdef FULL_TRIE_STUDY
-           else if (PL_regkind[OP(scan)] == TRIE) {
-               /* NOTE - There is similar code to this block above for handling
-                  BRANCH nodes on the initial study.  If you change stuff here
-                  check there too. */
-               regnode *trie_node= scan;
-               regnode *tail= regnext(scan);
-               reg_trie_data *trie = (reg_trie_data*)RExC_rx->data->data[ ARG(scan) ];
-               I32 max1 = 0, min1 = I32_MAX;
-               struct regnode_charclass_class accum;
-
-               if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
-                   scan_commit(pRExC_state, data,minlenp); /* Cannot merge strings after this. */
-               if (flags & SCF_DO_STCLASS)
-                   cl_init_zero(pRExC_state, &accum);
-
-               if (!trie->jump) {
-                   min1= trie->minlen;
-                   max1= trie->maxlen;
-               } else {
-                   const regnode *nextbranch= NULL;
-                   U32 word;
-
-                   for ( word=1 ; word <= trie->wordcount ; word++) 
-                   {
-                       I32 deltanext=0, minnext=0, f = 0, fake;
-                       struct regnode_charclass_class this_class;
-
-                       data_fake.flags = 0;
-                       if (data) {
-                           data_fake.whilem_c = data->whilem_c;
-                           data_fake.last_closep = data->last_closep;
-                       }
-                       else
-                           data_fake.last_closep = &fake;
-
-                       if (flags & SCF_DO_STCLASS) {
-                           cl_init(pRExC_state, &this_class);
-                           data_fake.start_class = &this_class;
-                           f = SCF_DO_STCLASS_AND;
-                       }
-                       if (flags & SCF_WHILEM_VISITED_POS)
-                           f |= SCF_WHILEM_VISITED_POS;
-
-                       if (trie->jump[word]) {
-                           if (!nextbranch)
-                               nextbranch = trie_node + trie->jump[0];
-                           scan= trie_node + trie->jump[word];
-                           /* We go from the jump point to the branch that follows
-                              it. Note this means we need the vestigal unused branches
-                              even though they arent otherwise used.
-                              */
-                           minnext = study_chunk(pRExC_state, &scan, minlenp, 
-                                   &deltanext, (regnode *)nextbranch, &data_fake, 
-                                   stopparen, recursed, NULL, f,depth+1);
-                       }
-                       if (nextbranch && PL_regkind[OP(nextbranch)]==BRANCH)
-                           nextbranch= regnext((regnode*)nextbranch);
-
-                       if (min1 > (I32)(minnext + trie->minlen))
-                           min1 = minnext + trie->minlen;
-                       if (max1 < (I32)(minnext + deltanext + trie->maxlen))
-                           max1 = minnext + deltanext + trie->maxlen;
-                       if (deltanext == I32_MAX)
-                           is_inf = is_inf_internal = 1;
-
-                       if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                           pars++;
-                       if (data_fake.flags & SCF_SEEN_ACCEPT) {
-                           if ( stopmin > min + min1) 
-                               stopmin = min + min1;
-                           flags &= ~SCF_DO_SUBSTR;
-                           if (data)
-                               data->flags |= SCF_SEEN_ACCEPT;
-                       }
-                       if (data) {
-                           if (data_fake.flags & SF_HAS_EVAL)
-                               data->flags |= SF_HAS_EVAL;
-                           data->whilem_c = data_fake.whilem_c;
-                       }
-                       if (flags & SCF_DO_STCLASS)
-                           cl_or(pRExC_state, &accum, &this_class);
-                   }
-               }
-               if (flags & SCF_DO_SUBSTR) {
-                   data->pos_min += min1;
-                   data->pos_delta += max1 - min1;
-                   if (max1 != min1 || is_inf)
-                       data->longest = &(data->longest_float);
-               }
-               min += min1;
-               delta += max1 - min1;
-               if (flags & SCF_DO_STCLASS_OR) {
-                   cl_or(pRExC_state, data->start_class, &accum);
-                   if (min1) {
-                       cl_and(data->start_class, and_withp);
-                       flags &= ~SCF_DO_STCLASS;
-                   }
-               }
-               else if (flags & SCF_DO_STCLASS_AND) {
-                   if (min1) {
-                       cl_and(data->start_class, &accum);
-                       flags &= ~SCF_DO_STCLASS;
-                   }
-                   else {
-                       /* Switch to OR mode: cache the old value of
-                        * data->start_class */
-                       INIT_AND_WITHP;
-                       StructCopy(data->start_class, and_withp,
-                               struct regnode_charclass_class);
-                       flags &= ~SCF_DO_STCLASS_AND;
-                       StructCopy(&accum, data->start_class,
-                               struct regnode_charclass_class);
-                       flags |= SCF_DO_STCLASS_OR;
-                       data->start_class->flags |= ANYOF_EOS;
-                   }
-               }
-               scan= tail;
-               continue;
-           }
+        else if (PL_regkind[OP(scan)] == TRIE) {
+            /* NOTE - There is similar code to this block above for handling
+               BRANCH nodes on the initial study.  If you change stuff here
+               check there too. */
+            regnode *trie_node= scan;
+            regnode *tail= regnext(scan);
+            reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
+            I32 max1 = 0, min1 = I32_MAX;
+            struct regnode_charclass_class accum;
+
+            if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
+                SCAN_COMMIT(pRExC_state, data,minlenp); /* Cannot merge strings after this. */
+            if (flags & SCF_DO_STCLASS)
+                cl_init_zero(pRExC_state, &accum);
+                
+            if (!trie->jump) {
+                min1= trie->minlen;
+                max1= trie->maxlen;
+            } else {
+                const regnode *nextbranch= NULL;
+                U32 word;
+                
+                for ( word=1 ; word <= trie->wordcount ; word++) 
+                {
+                    I32 deltanext=0, minnext=0, f = 0, fake;
+                    struct regnode_charclass_class this_class;
+                    
+                    data_fake.flags = 0;
+                    if (data) {
+                        data_fake.whilem_c = data->whilem_c;
+                        data_fake.last_closep = data->last_closep;
+                    }
+                    else
+                        data_fake.last_closep = &fake;
+                   data_fake.pos_delta = delta;
+                    if (flags & SCF_DO_STCLASS) {
+                        cl_init(pRExC_state, &this_class);
+                        data_fake.start_class = &this_class;
+                        f = SCF_DO_STCLASS_AND;
+                    }
+                    if (flags & SCF_WHILEM_VISITED_POS)
+                        f |= SCF_WHILEM_VISITED_POS;
+    
+                    if (trie->jump[word]) {
+                        if (!nextbranch)
+                            nextbranch = trie_node + trie->jump[0];
+                        scan= trie_node + trie->jump[word];
+                        /* We go from the jump point to the branch that follows
+                           it. Note this means we need the vestigal unused branches
+                           even though they arent otherwise used.
+                         */
+                        minnext = study_chunk(pRExC_state, &scan, minlenp, 
+                            &deltanext, (regnode *)nextbranch, &data_fake, 
+                            stopparen, recursed, NULL, f,depth+1);
+                    }
+                    if (nextbranch && PL_regkind[OP(nextbranch)]==BRANCH)
+                        nextbranch= regnext((regnode*)nextbranch);
+                    
+                    if (min1 > (I32)(minnext + trie->minlen))
+                        min1 = minnext + trie->minlen;
+                    if (max1 < (I32)(minnext + deltanext + trie->maxlen))
+                        max1 = minnext + deltanext + trie->maxlen;
+                    if (deltanext == I32_MAX)
+                        is_inf = is_inf_internal = 1;
+                    
+                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
+                        pars++;
+                    if (data_fake.flags & SCF_SEEN_ACCEPT) {
+                        if ( stopmin > min + min1) 
+                           stopmin = min + min1;
+                       flags &= ~SCF_DO_SUBSTR;
+                       if (data)
+                           data->flags |= SCF_SEEN_ACCEPT;
+                   }
+                    if (data) {
+                        if (data_fake.flags & SF_HAS_EVAL)
+                            data->flags |= SF_HAS_EVAL;
+                        data->whilem_c = data_fake.whilem_c;
+                    }
+                    if (flags & SCF_DO_STCLASS)
+                        cl_or(pRExC_state, &accum, &this_class);
+                }
+            }
+            if (flags & SCF_DO_SUBSTR) {
+                data->pos_min += min1;
+                data->pos_delta += max1 - min1;
+                if (max1 != min1 || is_inf)
+                    data->longest = &(data->longest_float);
+            }
+            min += min1;
+            delta += max1 - min1;
+            if (flags & SCF_DO_STCLASS_OR) {
+                cl_or(pRExC_state, data->start_class, &accum);
+                if (min1) {
+                    cl_and(data->start_class, and_withp);
+                    flags &= ~SCF_DO_STCLASS;
+                }
+            }
+            else if (flags & SCF_DO_STCLASS_AND) {
+                if (min1) {
+                    cl_and(data->start_class, &accum);
+                    flags &= ~SCF_DO_STCLASS;
+                }
+                else {
+                    /* Switch to OR mode: cache the old value of
+                     * data->start_class */
+                   INIT_AND_WITHP;
+                    StructCopy(data->start_class, and_withp,
+                               struct regnode_charclass_class);
+                    flags &= ~SCF_DO_STCLASS_AND;
+                    StructCopy(&accum, data->start_class,
+                               struct regnode_charclass_class);
+                    flags |= SCF_DO_STCLASS_OR;
+                    data->start_class->flags |= ANYOF_EOS;
+                }
+            }
+            scan= tail;
+            continue;
+        }
 #else
-           else if (PL_regkind[OP(scan)] == TRIE) {
-               reg_trie_data *trie = (reg_trie_data*)RExC_rx->data->data[ ARG(scan) ];
-               U8*bang=NULL;
-
-               min += trie->minlen;
-               delta += (trie->maxlen - trie->minlen);
-               flags &= ~SCF_DO_STCLASS; /* xxx */
-               if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);      /* Cannot expect anything... */
-                   data->pos_min += trie->minlen;
-                   data->pos_delta += (trie->maxlen - trie->minlen);
-                   if (trie->maxlen != trie->minlen)
-                       data->longest = &(data->longest_float);
-               }
-               if (trie->jump) /* no more substrings -- for now /grr*/
-                   flags &= ~SCF_DO_SUBSTR;
-           }
-#endif /* old or new */
-#endif /* TRIE_STUDY_OPT */
-           /* Else: zero-length, ignore. */
-           scan = regnext(scan);
+       else if (PL_regkind[OP(scan)] == TRIE) {
+           reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
+           U8*bang=NULL;
+           
+           min += trie->minlen;
+           delta += (trie->maxlen - trie->minlen);
+           flags &= ~SCF_DO_STCLASS; /* xxx */
+            if (flags & SCF_DO_SUBSTR) {
+               SCAN_COMMIT(pRExC_state,data,minlenp);  /* Cannot expect anything... */
+               data->pos_min += trie->minlen;
+               data->pos_delta += (trie->maxlen - trie->minlen);
+               if (trie->maxlen != trie->minlen)
+                   data->longest = &(data->longest_float);
+           }
+           if (trie->jump) /* no more substrings -- for now /grr*/
+               flags &= ~SCF_DO_SUBSTR; 
        }
-       DEBUG_PEEP("FEND",scan,depth);
-       scan = frame->next;
-       stopparen = frame->stop;
-       frame = frame->prev;
-
+#endif /* old or new */
+#endif /* TRIE_STUDY_OPT */    
+       /* Else: zero-length, ignore. */
+       scan = regnext(scan);
+    }
+    if (frame) {
+        last = frame->last;
+        scan = frame->next;
+        stopparen = frame->stop;
+        frame = frame->prev;
+        goto fake_study_recurse;
     }
 
   finish:
+    assert(!frame);
+    DEBUG_STUDYDATA("pre-fin:",data,depth);
+
     *scanp = scan;
     *deltap = is_inf_internal ? I32_MAX : delta;
     if (flags & SCF_DO_SUBSTR && is_inf)
@@ -3804,32 +3890,29 @@ do_default:
     if (flags & SCF_TRIE_RESTUDY)
         data->flags |=         SCF_TRIE_RESTUDY;
     
-    DEBUG_STUDYDATA(data,depth);
+    DEBUG_STUDYDATA("post-fin:",data,depth);
     
     return min < stopmin ? min : stopmin;
 }
 
-STATIC I32
-S_add_data(RExC_state_t *pRExC_state, I32 n, const char *s)
+STATIC U32
+S_add_data(RExC_state_t *pRExC_state, U32 n, const char *s)
 {
-    if (RExC_rx->data) {
-       const U32 count = RExC_rx->data->count;
-       Renewc(RExC_rx->data,
-              sizeof(*RExC_rx->data) + sizeof(void*) * (count + n - 1),
-              char, struct reg_data);
-       Renew(RExC_rx->data->what, count + n, U8);
-       RExC_rx->data->count += n;
-    }
-    else {
-       Newxc(RExC_rx->data, sizeof(*RExC_rx->data) + sizeof(void*) * (n - 1),
-            char, struct reg_data);
-       Newx(RExC_rx->data->what, n, U8);
-       RExC_rx->data->count = n;
-    }
-    Copy(s, RExC_rx->data->what + RExC_rx->data->count - n, n, U8);
-    return RExC_rx->data->count - n;
+    U32 count = RExC_rxi->data ? RExC_rxi->data->count : 0;
+
+    Renewc(RExC_rxi->data,
+          sizeof(*RExC_rxi->data) + sizeof(void*) * (count + n - 1),
+          char, struct reg_data);
+    if(count)
+       Renew(RExC_rxi->data->what, count + n, U8);
+    else
+       Newx(RExC_rxi->data->what, n, U8);
+    RExC_rxi->data->count = count + n;
+    Copy(s, RExC_rxi->data->what + count, n, U8);
+    return count;
 }
 
+/*XXX: todo make this not included in a non debugging perl */
 #ifndef PERL_IN_XSUB_RE
 void
 Perl_reginitcolors(pTHX)
@@ -3893,23 +3976,18 @@ Perl_reginitcolors(pTHX)
 extern const struct regexp_engine my_reg_engine;
 #define RE_ENGINE_PTR &my_reg_engine
 #endif
-/* these make a few things look better, to avoid indentation */
-#define BEGIN_BLOCK {
-#define END_BLOCK }
+
+#ifndef PERL_IN_XSUB_RE 
 regexp *
 Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
 {
     dVAR;
-    GET_RE_DEBUG_FLAGS_DECL;
-    DEBUG_r(if (!PL_colorset) reginitcolors());
-#ifndef PERL_IN_XSUB_RE
-    BEGIN_BLOCK
+    HV * const table = GvHV(PL_hintgv);
     /* Dispatch a request to compile a regexp to correct 
        regexp engine. */
-    HV * const table = GvHV(PL_hintgv);
     if (table) {
         SV **ptr= hv_fetchs(table, "regcomp", FALSE);
+        GET_RE_DEBUG_FLAGS_DECL;
         if (ptr && SvIOK(*ptr) && SvIV(*ptr)) {
             const regexp_engine *eng=INT2PTR(regexp_engine*,SvIV(*ptr));
             DEBUG_COMPILE_r({
@@ -3919,10 +3997,16 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
             return CALLREGCOMP_ENG(eng, exp, xend, pm);
         } 
     }
-    END_BLOCK
+    return Perl_re_compile(aTHX_ exp, xend, pm);
+}
 #endif
-    BEGIN_BLOCK    
+
+regexp *
+Perl_re_compile(pTHX_ char *exp, char *xend, PMOP *pm)
+{
+    dVAR;
     register regexp *r;
+    register regexp_internal *ri;
     regnode *scan;
     regnode *first;
     I32 flags;
@@ -3936,6 +4020,9 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     int restudied= 0;
     RExC_state_t copyRExC_state;
 #endif    
+    GET_RE_DEBUG_FLAGS_DECL;
+    DEBUG_r(if (!PL_colorset) reginitcolors());
+        
     if (exp == NULL)
        FAIL("NULL regexp argument");
 
@@ -3963,7 +4050,6 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_end = xend;
     RExC_naughty = 0;
     RExC_npar = 1;
-    RExC_cpar = 1;
     RExC_nestroot = 0;
     RExC_size = 0L;
     RExC_emit = &PL_regdummy;
@@ -3973,6 +4059,9 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_close_parens = NULL;
     RExC_opend = NULL;
     RExC_paren_names = NULL;
+#ifdef DEBUGGING
+    RExC_paren_name_list = NULL;
+#endif
     RExC_recurse = NULL;
     RExC_recurse_count = 0;
 
@@ -4010,32 +4099,28 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     /* Allocate space and zero-initialize. Note, the two step process 
        of zeroing when in debug mode, thus anything assigned has to 
        happen after that */
-    Newxc(r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode),
-        char, regexp);
-    if (r == NULL)
+    Newxz(r, 1, regexp);
+    Newxc(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode),
+        char, regexp_internal);
+    if ( r == NULL || ri == NULL )
        FAIL("Regexp out of space");
 #ifdef DEBUGGING
     /* avoid reading uninitialized memory in DEBUGGING code in study_chunk() */
-    Zero(r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode), char);
+    Zero(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode), char);
+#else 
+    /* bulk initialize base fields with 0. */
+    Zero(ri, sizeof(regexp_internal), char);        
 #endif
-    /* initialization begins here */
+
+    /* non-zero initialization begins here */
+    RXi_SET( r, ri );
     r->engine= RE_ENGINE_PTR;
     r->refcnt = 1;
     r->prelen = xend - exp;
     r->precomp = savepvn(RExC_precomp, r->prelen);
-    r->subbeg = NULL;
-#ifdef PERL_OLD_COPY_ON_WRITE
-    r->saved_copy = NULL;
-#endif
-    r->reganch = pm->op_pmflags & PMf_COMPILETIME;
+    r->extflags = pm->op_pmflags & RXf_PMf_COMPILETIME;
+    r->intflags = 0;
     r->nparens = RExC_npar - 1;        /* set early to validate backrefs */
-    r->lastparen = 0;                  /* mg.c reads this.  */
-
-    r->substrs = 0;                    /* Useful during FAIL. */
-    r->startp = 0;                     /* Useful during FAIL. */
-    r->endp = 0;                       
-    r->swap = NULL; 
-    r->paren_names = 0;
     
     if (RExC_seen & REG_SEEN_RECURSE) {
         Newxz(RExC_open_parens, RExC_npar,regnode *);
@@ -4045,16 +4130,17 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     }
 
     /* Useful during FAIL. */
-    Newxz(r->offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
-    if (r->offsets) {
-       r->offsets[0] = RExC_size;
+    Newxz(ri->offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
+    if (ri->offsets) {
+       ri->offsets[0] = RExC_size;
     }
     DEBUG_OFFSETS_r(PerlIO_printf(Perl_debug_log,
                           "%s %"UVuf" bytes for offset annotations.\n",
-                          r->offsets ? "Got" : "Couldn't get",
+                          ri->offsets ? "Got" : "Couldn't get",
                           (UV)((2*RExC_size+1) * sizeof(U32))));
 
     RExC_rx = r;
+    RExC_rxi = ri;
 
     /* Second pass: emit code. */
     RExC_flags = pm->op_pmflags;       /* don't let top level (?i) bleed */
@@ -4062,18 +4148,16 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_end = xend;
     RExC_naughty = 0;
     RExC_npar = 1;
-    RExC_cpar = 1;
-    RExC_emit_start = r->program;
-    RExC_emit = r->program;
+    RExC_emit_start = ri->program;
+    RExC_emit = ri->program;
 #ifdef DEBUGGING
     /* put a sentinal on the end of the program so we can check for
        overwrites */
-    r->program[RExC_size].type = 255;
+    ri->program[RExC_size].type = 255;
 #endif
     /* Store the count of eval-groups for security checks: */
-    RExC_emit->next_off = (RExC_seen_evals > (I32)U16_MAX) ? U16_MAX : (U16)RExC_seen_evals;
+    RExC_rx->seen_evals = RExC_seen_evals;
     REGC((U8)REG_MAGIC, (char*) RExC_emit++);
-    r->data = 0;
     if (reg(pRExC_state, 0, &flags,1) == NULL)
        return(NULL);
 
@@ -4114,14 +4198,14 @@ reStudy:
 #endif    
 
     /* Dig out information for optimizations. */
-    r->reganch = pm->op_pmflags & PMf_COMPILETIME; /* Again? */
+    r->extflags = pm->op_pmflags & RXf_PMf_COMPILETIME; /* Again? */
     pm->op_pmflags = RExC_flags;
     if (UTF)
-        r->reganch |= ROPT_UTF8;       /* Unicode in it? */
-    r->regstclass = NULL;
+        r->extflags |= RXf_UTF8;       /* Unicode in it? */
+    ri->regstclass = NULL;
     if (RExC_naughty >= 10)    /* Probably an expensive pattern. */
-       r->reganch |= ROPT_NAUGHTY;
-    scan = r->program + 1;             /* First BRANCH. */
+       r->intflags |= PREGf_NAUGHTY;
+    scan = ri->program + 1;            /* First BRANCH. */
 
     /* testing for BRANCH here tells us whether there is "must appear"
        data in the pattern. If there is then we can use it for optimisations */
@@ -4164,67 +4248,68 @@ reStudy:
            if (OP(first) == EXACT)
                NOOP;   /* Empty, get anchored substr later. */
            else if ((OP(first) == EXACTF || OP(first) == EXACTFL))
-               r->regstclass = first;
+               ri->regstclass = first;
        }
 #ifdef TRIE_STCLASS    
        else if (PL_regkind[OP(first)] == TRIE &&
-               ((reg_trie_data *)r->data->data[ ARG(first) ])->minlen>0) 
+               ((reg_trie_data *)ri->data->data[ ARG(first) ])->minlen>0) 
        {
            regnode *trie_op;
            /* this can happen only on restudy */
            if ( OP(first) == TRIE ) {
-                struct regnode_1 *trieop;
-                Newxz(trieop,1,struct regnode_1);
+                struct regnode_1 *trieop = (struct regnode_1 *)
+                   PerlMemShared_calloc(1, sizeof(struct regnode_1));
                 StructCopy(first,trieop,struct regnode_1);
                 trie_op=(regnode *)trieop;
             } else {
-                struct regnode_charclass *trieop;
-                Newxz(trieop,1,struct regnode_charclass);
+                struct regnode_charclass *trieop = (struct regnode_charclass *)
+                   PerlMemShared_calloc(1, sizeof(struct regnode_charclass));
                 StructCopy(first,trieop,struct regnode_charclass);
                 trie_op=(regnode *)trieop;
             }
             OP(trie_op)+=2;
             make_trie_failtable(pRExC_state, (regnode *)first, trie_op, 0);
-           r->regstclass = trie_op;
+           ri->regstclass = trie_op;
        }
 #endif 
        else if (strchr((const char*)PL_simple,OP(first)))
-           r->regstclass = first;
+           ri->regstclass = first;
        else if (PL_regkind[OP(first)] == BOUND ||
                 PL_regkind[OP(first)] == NBOUND)
-           r->regstclass = first;
+           ri->regstclass = first;
        else if (PL_regkind[OP(first)] == BOL) {
-           r->reganch |= (OP(first) == MBOL
-                          ? ROPT_ANCH_MBOL
+           r->extflags |= (OP(first) == MBOL
+                          ? RXf_ANCH_MBOL
                           : (OP(first) == SBOL
-                             ? ROPT_ANCH_SBOL
-                             : ROPT_ANCH_BOL));
+                             ? RXf_ANCH_SBOL
+                             : RXf_ANCH_BOL));
            first = NEXTOPER(first);
            goto again;
        }
        else if (OP(first) == GPOS) {
-           r->reganch |= ROPT_ANCH_GPOS;
+           r->extflags |= RXf_ANCH_GPOS;
            first = NEXTOPER(first);
            goto again;
        }
        else if ((!sawopen || !RExC_sawback) &&
            (OP(first) == STAR &&
            PL_regkind[OP(NEXTOPER(first))] == REG_ANY) &&
-           !(r->reganch & ROPT_ANCH) )
+           !(r->extflags & RXf_ANCH) && !(RExC_seen & REG_SEEN_EVAL))
        {
            /* turn .* into ^.* with an implied $*=1 */
            const int type =
                (OP(NEXTOPER(first)) == REG_ANY)
-                   ? ROPT_ANCH_MBOL
-                   : ROPT_ANCH_SBOL;
-           r->reganch |= type | ROPT_IMPLICIT;
+                   ? RXf_ANCH_MBOL
+                   : RXf_ANCH_SBOL;
+           r->extflags |= type;
+           r->intflags |= PREGf_IMPLICIT;
            first = NEXTOPER(first);
            goto again;
        }
        if (sawplus && (!sawopen || !RExC_sawback)
            && !(RExC_seen & REG_SEEN_EVAL)) /* May examine pos and $& */
            /* x+ must match at the 1st pos of run of x's */
-           r->reganch |= ROPT_SKIP;
+           r->intflags |= PREGf_SKIP;
 
        /* Scan is after the zeroth branch, first is atomic matcher. */
 #ifdef TRIE_STUDY_OPT
@@ -4258,7 +4343,7 @@ reStudy:
        data.last_found = newSVpvs("");
        data.longest = &(data.longest_fixed);
        first = scan;
-       if (!r->regstclass) {
+       if (!ri->regstclass) {
            cl_init(pRExC_state, &ch_class);
            data.start_class = &ch_class;
            stclass_flag = SCF_DO_STCLASS_AND;
@@ -4277,9 +4362,10 @@ reStudy:
        if ( RExC_npar == 1 && data.longest == &(data.longest_fixed)
             && data.last_start_min == 0 && data.last_end > 0
             && !RExC_seen_zerolen
-            && (!(RExC_seen & REG_SEEN_GPOS) || (r->reganch & ROPT_ANCH_GPOS)))
-           r->reganch |= ROPT_CHECK_ALL;
-       scan_commit(pRExC_state, &data,&minlen);
+            && !(RExC_seen & REG_SEEN_VERBARG)
+            && (!(RExC_seen & REG_SEEN_GPOS) || (r->extflags & RXf_ANCH_GPOS)))
+           r->extflags |= RXf_CHECK_ALL;
+       scan_commit(pRExC_state, &data,&minlen,0);
        SvREFCNT_dec(data.last_found);
 
         /* Note that code very similar to this but for anchored string 
@@ -4290,7 +4376,7 @@ reStudy:
        if (longest_float_length
            || (data.flags & SF_FL_BEFORE_EOL
                && (!(data.flags & SF_FL_BEFORE_MEOL)
-                   || (RExC_flags & PMf_MULTILINE)))) 
+                   || (RExC_flags & RXf_PMf_MULTILINE)))) 
         {
             I32 t,ml;
 
@@ -4324,7 +4410,7 @@ reStudy:
            
            t = (data.flags & SF_FL_BEFORE_EOL /* Can't have SEOL and MULTI */
                       && (!(data.flags & SF_FL_BEFORE_MEOL)
-                          || (RExC_flags & PMf_MULTILINE)));
+                          || (RExC_flags & RXf_PMf_MULTILINE)));
            fbm_compile(data.longest_float, t ? FBMcf_TAIL : 0);
        }
        else {
@@ -4342,7 +4428,7 @@ reStudy:
        if (longest_fixed_length
            || (data.flags & SF_FIX_BEFORE_EOL /* Cannot have SEOL and MULTI */
                && (!(data.flags & SF_FIX_BEFORE_MEOL)
-                   || (RExC_flags & PMf_MULTILINE)))) 
+                   || (RExC_flags & RXf_PMf_MULTILINE)))) 
         {
             I32 t,ml;
 
@@ -4368,7 +4454,7 @@ reStudy:
 
            t = (data.flags & SF_FIX_BEFORE_EOL /* Can't have SEOL and MULTI */
                 && (!(data.flags & SF_FIX_BEFORE_MEOL)
-                    || (RExC_flags & PMf_MULTILINE)));
+                    || (RExC_flags & RXf_PMf_MULTILINE)));
            fbm_compile(data.longest_fixed, t ? FBMcf_TAIL : 0);
        }
        else {
@@ -4376,23 +4462,23 @@ reStudy:
            SvREFCNT_dec(data.longest_fixed);
            longest_fixed_length = 0;
        }
-       if (r->regstclass
-           && (OP(r->regstclass) == REG_ANY || OP(r->regstclass) == SANY))
-           r->regstclass = NULL;
+       if (ri->regstclass
+           && (OP(ri->regstclass) == REG_ANY || OP(ri->regstclass) == SANY))
+           ri->regstclass = NULL;
        if ((!(r->anchored_substr || r->anchored_utf8) || r->anchored_offset)
            && stclass_flag
            && !(data.start_class->flags & ANYOF_EOS)
            && !cl_is_anything(data.start_class))
        {
-           const I32 n = add_data(pRExC_state, 1, "f");
+           const U32 n = add_data(pRExC_state, 1, "f");
 
-           Newx(RExC_rx->data->data[n], 1,
+           Newx(RExC_rxi->data->data[n], 1,
                struct regnode_charclass_class);
            StructCopy(data.start_class,
-                      (struct regnode_charclass_class*)RExC_rx->data->data[n],
+                      (struct regnode_charclass_class*)RExC_rxi->data->data[n],
                       struct regnode_charclass_class);
-           r->regstclass = (regnode*)RExC_rx->data->data[n];
-           r->reganch &= ~ROPT_SKIP;   /* Used in find_byclass(). */
+           ri->regstclass = (regnode*)RExC_rxi->data->data[n];
+           r->intflags &= ~PREGf_SKIP; /* Used in find_byclass(). */
            DEBUG_COMPILE_r({ SV *sv = sv_newmortal();
                      regprop(r, sv, (regnode*)data.start_class);
                      PerlIO_printf(Perl_debug_log,
@@ -4406,8 +4492,8 @@ reStudy:
            r->check_substr = r->anchored_substr;
            r->check_utf8 = r->anchored_utf8;
            r->check_offset_min = r->check_offset_max = r->anchored_offset;
-           if (r->reganch & ROPT_ANCH_SINGLE)
-               r->reganch |= ROPT_NOSCAN;
+           if (r->extflags & RXf_ANCH_SINGLE)
+               r->extflags |= RXf_NOSCAN;
        }
        else {
            r->check_end_shift = r->float_end_shift;
@@ -4418,10 +4504,10 @@ reStudy:
        }
        /* XXXX Currently intuiting is not compatible with ANCH_GPOS.
           This should be changed ASAP!  */
-       if ((r->check_substr || r->check_utf8) && !(r->reganch & ROPT_ANCH_GPOS)) {
-           r->reganch |= RE_USE_INTUIT;
+       if ((r->check_substr || r->check_utf8) && !(r->extflags & RXf_ANCH_GPOS)) {
+           r->extflags |= RXf_USE_INTUIT;
            if (SvTAIL(r->check_substr ? r->check_substr : r->check_utf8))
-               r->reganch |= RE_INTUIT_TAIL;
+               r->extflags |= RXf_INTUIT_TAIL;
        }
        /* XXX Unneeded? dmq (shouldn't as this is handled elsewhere)
        if ( (STRLEN)minlen < longest_float_length )
@@ -4438,7 +4524,7 @@ reStudy:
        
        DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "\nMulti Top Level\n"));
 
-       scan = r->program + 1;
+       scan = ri->program + 1;
        cl_init(pRExC_state, &ch_class);
        data.start_class = &ch_class;
        data.last_closep = &last_close;
@@ -4454,15 +4540,15 @@ reStudy:
        if (!(data.start_class->flags & ANYOF_EOS)
            && !cl_is_anything(data.start_class))
        {
-           const I32 n = add_data(pRExC_state, 1, "f");
+           const U32 n = add_data(pRExC_state, 1, "f");
 
-           Newx(RExC_rx->data->data[n], 1,
+           Newx(RExC_rxi->data->data[n], 1,
                struct regnode_charclass_class);
            StructCopy(data.start_class,
-                      (struct regnode_charclass_class*)RExC_rx->data->data[n],
+                      (struct regnode_charclass_class*)RExC_rxi->data->data[n],
                       struct regnode_charclass_class);
-           r->regstclass = (regnode*)RExC_rx->data->data[n];
-           r->reganch &= ~ROPT_SKIP;   /* Used in find_byclass(). */
+           ri->regstclass = (regnode*)RExC_rxi->data->data[n];
+           r->intflags &= ~PREGf_SKIP; /* Used in find_byclass(). */
            DEBUG_COMPILE_r({ SV* sv = sv_newmortal();
                      regprop(r, sv, (regnode*)data.start_class);
                      PerlIO_printf(Perl_debug_log,
@@ -4475,29 +4561,41 @@ reStudy:
        the "real" pattern. */
     DEBUG_OPTIMISE_r({
        PerlIO_printf(Perl_debug_log,"minlen: %"IVdf" r->minlen:%"IVdf"\n",
-           minlen, r->minlen);
+                     (IV)minlen, (IV)r->minlen);
     });
     r->minlenret = minlen;
     if (r->minlen < minlen) 
         r->minlen = minlen;
     
     if (RExC_seen & REG_SEEN_GPOS)
-       r->reganch |= ROPT_GPOS_SEEN;
+       r->extflags |= RXf_GPOS_SEEN;
     if (RExC_seen & REG_SEEN_LOOKBEHIND)
-       r->reganch |= ROPT_LOOKBEHIND_SEEN;
+       r->extflags |= RXf_LOOKBEHIND_SEEN;
     if (RExC_seen & REG_SEEN_EVAL)
-       r->reganch |= ROPT_EVAL_SEEN;
+       r->extflags |= RXf_EVAL_SEEN;
     if (RExC_seen & REG_SEEN_CANY)
-       r->reganch |= ROPT_CANY_SEEN;
+       r->extflags |= RXf_CANY_SEEN;
     if (RExC_seen & REG_SEEN_VERBARG)
-       r->reganch |= ROPT_VERBARG_SEEN;
+       r->intflags |= PREGf_VERBARG_SEEN;
     if (RExC_seen & REG_SEEN_CUTGROUP)
-       r->reganch |= ROPT_CUTGROUP_SEEN;
+       r->intflags |= PREGf_CUTGROUP_SEEN;
     if (RExC_paren_names)
         r->paren_names = (HV*)SvREFCNT_inc(RExC_paren_names);
     else
         r->paren_names = NULL;
-               
+    if (r->prelen == 3 && strEQ("\\s+", r->precomp))
+       r->extflags |= RXf_WHITE;
+    else if (r->prelen == 1 && r->precomp[0] == '^')
+        r->extflags |= RXf_START_ONLY;
+
+#ifdef DEBUGGING
+    if (RExC_paren_names) {
+        ri->name_list_idx = add_data( pRExC_state, 1, "p" );
+        ri->data->data[ri->name_list_idx] = (void*)SvREFCNT_inc(RExC_paren_name_list);
+    } else
+#endif
+        ri->name_list_idx = 0;
+
     if (RExC_recurse_count) {
         for ( ; RExC_recurse_count ; RExC_recurse_count-- ) {
             const regnode *scan = RExC_recurse[RExC_recurse_count-1];
@@ -4512,33 +4610,35 @@ reStudy:
         PerlIO_printf(Perl_debug_log,"Final program:\n");
         regdump(r);
     });
-    DEBUG_OFFSETS_r(if (r->offsets) {
-        const U32 len = r->offsets[0];
+    DEBUG_OFFSETS_r(if (ri->offsets) {
+        const U32 len = ri->offsets[0];
         U32 i;
         GET_RE_DEBUG_FLAGS_DECL;
-        PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)r->offsets[0]);
+        PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)ri->offsets[0]);
         for (i = 1; i <= len; i++) {
-            if (r->offsets[i*2-1] || r->offsets[i*2])
+            if (ri->offsets[i*2-1] || ri->offsets[i*2])
                 PerlIO_printf(Perl_debug_log, "%"UVuf":%"UVuf"[%"UVuf"] ",
-                (UV)i, (UV)r->offsets[i*2-1], (UV)r->offsets[i*2]);
+                (UV)i, (UV)ri->offsets[i*2-1], (UV)ri->offsets[i*2]);
             }
         PerlIO_printf(Perl_debug_log, "\n");
     });
     return(r);
-    END_BLOCK    
 }
 
 #undef CORE_ONLY_BLOCK
-#undef END_BLOCK
 #undef RE_ENGINE_PTR
 
 #ifndef PERL_IN_XSUB_RE
 SV*
-Perl_reg_named_buff_sv(pTHX_ SV* namesv)
+Perl_reg_named_buff_get(pTHX_ SV* namesv, const REGEXP * const from_re, U32 flags)
 {
-    I32 parno = 0; /* no match */
-    if (PL_curpm) {
-        const REGEXP * const rx = PM_GETRE(PL_curpm);
+    AV *retarray = NULL;
+    SV *ret;
+    if (flags & 1) 
+        retarray=newAV();
+    
+    if (from_re || PL_curpm) {
+        const REGEXP * const rx = from_re ? from_re : PM_GETRE(PL_curpm);
         if (rx && rx->paren_names) {            
             HE *he_str = hv_fetch_ent( rx->paren_names, namesv, 0, 0 );
             if (he_str) {
@@ -4549,22 +4649,100 @@ Perl_reg_named_buff_sv(pTHX_ SV* namesv)
                     if ((I32)(rx->lastparen) >= nums[i] &&
                         rx->endp[nums[i]] != -1) 
                     {
-                        parno = nums[i];
-                        break;
+                        ret = reg_numbered_buff_get(nums[i],rx,NULL,0);
+                        if (!retarray) 
+                            return ret;
+                    } else {
+                        ret = newSVsv(&PL_sv_undef);
+                    }
+                    if (retarray) {
+                        SvREFCNT_inc(ret); 
+                        av_push(retarray, ret);
                     }
                 }
+                if (retarray)
+                    return (SV*)retarray;
             }
         }
     }
-    if ( !parno ) {
-        return 0;
+    return NULL;
+}
+
+SV*
+Perl_reg_numbered_buff_get(pTHX_ I32 paren, const REGEXP * const rx, SV* usesv, U32 flags)
+{
+    char *s = NULL;
+    I32 i = 0;
+    I32 s1, t1;
+    SV *sv = usesv ? usesv : newSVpvs("");
+    PERL_UNUSED_ARG(flags);
+        
+    if (!rx->subbeg) {
+        sv_setsv(sv,&PL_sv_undef);
+        return sv;
+    } 
+    else               
+    if (paren == -2 && rx->startp[0] != -1) {
+        /* $` */
+       i = rx->startp[0];
+       s = rx->subbeg;
+    }
+    else 
+    if (paren == -1 && rx->endp[0] != -1) {
+        /* $' */
+       s = rx->subbeg + rx->endp[0];
+       i = rx->sublen - rx->endp[0];
+    } 
+    else
+    if ( 0 <= paren && paren <= (I32)rx->nparens &&
+        (s1 = rx->startp[paren]) != -1 &&
+        (t1 = rx->endp[paren]) != -1)
+    {
+        /* $& $1 ... */
+        i = t1 - s1;
+        s = rx->subbeg + s1;
+    } else {
+        sv_setsv(sv,&PL_sv_undef);
+        return sv;
+    }          
+    assert(rx->sublen >= (s - rx->subbeg) + i );
+    if (i >= 0) {
+        const int oldtainted = PL_tainted;
+        TAINT_NOT;
+        sv_setpvn(sv, s, i);
+        PL_tainted = oldtainted;
+        if ( (rx->extflags & RXf_CANY_SEEN)
+            ? (RX_MATCH_UTF8(rx)
+                        && (!i || is_utf8_string((U8*)s, i)))
+            : (RX_MATCH_UTF8(rx)) )
+        {
+            SvUTF8_on(sv);
+        }
+        else
+            SvUTF8_off(sv);
+        if (PL_tainting) {
+            if (RX_MATCH_TAINTED(rx)) {
+                if (SvTYPE(sv) >= SVt_PVMG) {
+                    MAGIC* const mg = SvMAGIC(sv);
+                    MAGIC* mgt;
+                    PL_tainted = 1;
+                    SvMAGIC_set(sv, mg->mg_moremagic);
+                    SvTAINT(sv);
+                    if ((mgt = SvMAGIC(sv))) {
+                        mg->mg_moremagic = mgt;
+                        SvMAGIC_set(sv, mg);
+                    }
+                } else {
+                    PL_tainted = 1;
+                    SvTAINT(sv);
+                }
+            } else 
+                SvTAINTED_off(sv);
+        }
     } else {
-        GV *gv_paren;
-        SV *sv= sv_newmortal();
-        Perl_sv_setpvf(aTHX_ sv, "%"IVdf,(IV)parno);
-        gv_paren= Perl_gv_fetchsv(aTHX_ sv, GV_ADD, SVt_PVGV);
-        return GvSVn(gv_paren);
+        sv_setsv(sv,&PL_sv_undef);
     }
+    return sv;
 }
 #endif
 
@@ -4583,17 +4761,19 @@ Perl_reg_named_buff_sv(pTHX_ SV* namesv)
 STATIC SV*
 S_reg_scan_name(pTHX_ RExC_state_t *pRExC_state, U32 flags) {
     char *name_start = RExC_parse;
-    if ( UTF ) {
-       STRLEN numlen;
-        while( isIDFIRST_uni(utf8n_to_uvchr((U8*)RExC_parse,
-            RExC_end - RExC_parse, &numlen, UTF8_ALLOW_DEFAULT)))
-        {
-                RExC_parse += numlen;
-        }
-    } else {
-        while( isIDFIRST(*RExC_parse) )
-           RExC_parse++;
+
+    if (isIDFIRST_lazy_if(RExC_parse, UTF)) {
+        /* skip IDFIRST by using do...while */
+       if (UTF)
+           do {
+               RExC_parse += UTF8SKIP(RExC_parse);
+           } while (isALNUM_utf8((U8*)RExC_parse));
+       else
+           do {
+               RExC_parse++;
+           } while (isALNUM(*RExC_parse));
     }
+
     if ( flags ) {
         SV* sv_name = sv_2mortal(Perl_newSVpvn(aTHX_ name_start,
             (int)(RExC_parse - name_start)));
@@ -4810,7 +4990,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                         if (start_arg) {
                             SV *sv = newSVpvn( start_arg, RExC_parse - start_arg);
                             ARG(ret) = add_data( pRExC_state, 1, "S" );
-                            RExC_rx->data->data[ARG(ret)]=(void*)sv;
+                            RExC_rxi->data->data[ARG(ret)]=(void*)sv;
                             ret->flags = 0;
                         } else {
                             ret->flags = 1; 
@@ -4829,8 +5009,6 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            return ret;
         } else 
        if (*RExC_parse == '?') { /* (?...) */
-           U32 posflags = 0, negflags = 0;
-           U32 *flagsp = &posflags;
            bool is_logical = 0;
            const char * const seqstart = RExC_parse;
 
@@ -4839,10 +5017,46 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            ret = NULL;                 /* For look-ahead/behind. */
            switch (paren) {
 
+           case 'P':   /* (?P...) variants for those used to PCRE/Python */
+               paren = *RExC_parse++;
+               if ( paren == '<')         /* (?P<...>) named capture */
+                   goto named_capture;
+                else if (paren == '>') {   /* (?P>name) named recursion */
+                    goto named_recursion;
+                }
+                else if (paren == '=') {   /* (?P=...)  named backref */
+                    /* this pretty much dupes the code for \k<NAME> in regatom(), if
+                       you change this make sure you change that */
+                    char* name_start = RExC_parse;
+                   U32 num = 0;
+                    SV *sv_dat = reg_scan_name(pRExC_state,
+                        SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
+                    if (RExC_parse == name_start || *RExC_parse != ')')
+                        vFAIL2("Sequence %.3s... not terminated",parse_start);
+
+                    if (!SIZE_ONLY) {
+                        num = add_data( pRExC_state, 1, "S" );
+                        RExC_rxi->data->data[num]=(void*)sv_dat;
+                        SvREFCNT_inc(sv_dat);
+                    }
+                    RExC_sawback = 1;
+                    ret = reganode(pRExC_state,
+                          (U8)(FOLD ? (LOC ? NREFFL : NREFF) : NREF),
+                          num);
+                    *flagp |= HASWIDTH;
+
+                    Set_Node_Offset(ret, parse_start+1);
+                    Set_Node_Cur_Length(ret); /* MJD */
+
+                    nextchar(pRExC_state);
+                    return ret;
+                }
+                goto unknown;
            case '<':           /* (?<...) */
                if (*RExC_parse == '!')
                    paren = ',';
                else if (*RExC_parse != '=') 
+              named_capture:
                {               /* (?<...>) */
                    char *name_start;
                    SV *svname;
@@ -4867,6 +5081,10 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                         if (!RExC_paren_names) {
                             RExC_paren_names= newHV();
                             sv_2mortal((SV*)RExC_paren_names);
+#ifdef DEBUGGING
+                            RExC_paren_name_list= newAV();
+                            sv_2mortal((SV*)RExC_paren_name_list);
+#endif
                         }
                         he_str = hv_fetch_ent( RExC_paren_names, svname, 1, 0 );
                         if ( he_str )
@@ -4887,6 +5105,10 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                             SvIOK_on(sv_dat);
                             SvIVX(sv_dat)= 1;
                         }
+#ifdef DEBUGGING
+                        if (!av_store(RExC_paren_name_list, RExC_npar, SvREFCNT_inc(svname)))
+                            SvREFCNT_dec(svname);
+#endif
 
                         /*sv_dump(sv_dat);*/
                     }
@@ -4929,9 +5151,9 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                /*notreached*/
             { /* named and numeric backreferences */
                 I32 num;
-                char * parse_start;
             case '&':            /* (?&NAME) */
                 parse_start = RExC_parse - 1;
+              named_recursion:
                 {
                    SV *sv_dat = reg_scan_name(pRExC_state,
                        SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
@@ -5021,7 +5243,8 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                /* FALL THROUGH */
            case '{':           /* (?{...}) */
            {
-               I32 count = 1, n = 0;
+               I32 count = 1;
+               U32 n = 0;
                char c;
                char *s = RExC_parse;
 
@@ -5056,9 +5279,9 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                    LEAVE;
 
                    n = add_data(pRExC_state, 3, "nop");
-                   RExC_rx->data->data[n] = (void*)rop;
-                   RExC_rx->data->data[n+1] = (void*)sop;
-                   RExC_rx->data->data[n+2] = (void*)pad;
+                   RExC_rxi->data->data[n] = (void*)rop;
+                   RExC_rxi->data->data[n+1] = (void*)sop;
+                   RExC_rxi->data->data[n+2] = (void*)pad;
                    SvREFCNT_dec(sv);
                }
                else {                                          /* First pass */
@@ -5110,7 +5333,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                {
                    char ch = RExC_parse[0] == '<' ? '>' : '\'';
                    char *name_start= RExC_parse++;
-                   I32 num = 0;
+                   U32 num = 0;
                    SV *sv_dat=reg_scan_name(pRExC_state,
                        SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
                    if (RExC_parse == name_start || *RExC_parse != ch)
@@ -5119,7 +5342,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                     RExC_parse++;
                    if (!SIZE_ONLY) {
                         num = add_data( pRExC_state, 1, "S" );
-                        RExC_rx->data->data[num]=(void*)sv_dat;
+                        RExC_rxi->data->data[num]=(void*)sv_dat;
                         SvREFCNT_inc(sv_dat);
                     }
                     ret = reganode(pRExC_state,NGROUPP,num);
@@ -5209,13 +5432,20 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                 vFAIL("Sequence (? incomplete");
                 break;
            default:
-               --RExC_parse;
-             parse_flags:      /* (?i) */
-               while (*RExC_parse && strchr("iogcmsx", *RExC_parse)) {
+               --RExC_parse;
+               parse_flags:      /* (?i) */  
+           {
+                U32 posflags = 0, negflags = 0;
+               U32 *flagsp = &posflags;
+
+               while (*RExC_parse) {
+                   /* && strchr("iogcmsx", *RExC_parse) */
                    /* (?g), (?gc) and (?o) are useless here
                       and must be globally applied -- japhy */
-
-                   if (*RExC_parse == 'o' || *RExC_parse == 'g') {
+                    switch (*RExC_parse) {
+                   CASE_STD_PMMOD_FLAGS_PARSE_SET(flagsp);
+                    case 'o':
+                    case 'g':
                        if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
                            const I32 wflagbit = *RExC_parse == 'o' ? WASTED_O : WASTED_G;
                            if (! (wastedflags & wflagbit) ) {
@@ -5230,8 +5460,9 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                                );
                            }
                        }
-                   }
-                   else if (*RExC_parse == 'c') {
+                       break;
+                       
+                   case 'c':
                        if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
                            if (! (wastedflags & WASTED_C) ) {
                                wastedflags |= WASTED_GC;
@@ -5243,33 +5474,45 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                                );
                            }
                        }
-                   }
-                   else { pmflag(flagsp, *RExC_parse); }
-
-                   ++RExC_parse;
-               }
-               if (*RExC_parse == '-') {
-                   flagsp = &negflags;
-                   wastedflags = 0;  /* reset so (?g-c) warns twice */
+                       break;
+                   case 'k':
+                        if (flagsp == &negflags) {
+                            if (SIZE_ONLY && ckWARN(WARN_REGEXP))
+                                vWARN(RExC_parse + 1,"Useless use of (?-k)");
+                        } else {
+                            *flagsp |= RXf_PMf_KEEPCOPY;
+                        }
+                       break;
+                    case '-':
+                        if (flagsp == &negflags)
+                            goto unknown;
+                       flagsp = &negflags;
+                       wastedflags = 0;  /* reset so (?g-c) warns twice */
+                       break;
+                    case ':':
+                       paren = ':';
+                       /*FALLTHROUGH*/
+                    case ')':
+                        RExC_flags |= posflags;
+                        RExC_flags &= ~negflags;
+                        nextchar(pRExC_state);
+                       if (paren != ':') {
+                           *flagp = TRYAGAIN;
+                           return NULL;
+                       } else {
+                            ret = NULL;
+                           goto parse_rest;
+                       }
+                       /*NOTREACHED*/
+                    default:
+                    unknown:
+                       RExC_parse++;
+                       vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
+                       /*NOTREACHED*/
+                    }                           
                    ++RExC_parse;
-                   goto parse_flags;
-               }
-               RExC_flags |= posflags;
-               RExC_flags &= ~negflags;
-               if (*RExC_parse == ':') {
-                   RExC_parse++;
-                   paren = ':';
-                   break;
-               }               
-             unknown:
-               if (*RExC_parse != ')') {
-                   RExC_parse++;
-                   vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
                }
-               nextchar(pRExC_state);
-               *flagp = TRYAGAIN;
-               return NULL;
-           }
+           }} /* one for the default block, one for the switch */
        }
        else {                  /* (...) */
          capturing_parens:
@@ -5294,7 +5537,8 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
     }
     else                        /* ! paren */
        ret = NULL;
-
+   
+   parse_rest:
     /* Pick up the branches, linking them together. */
     parse_start = RExC_parse;   /* MJD */
     br = regbranch(pRExC_state, &flags, 1,depth+1);
@@ -5351,7 +5595,6 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            ender = reg_node(pRExC_state, TAIL);
            break;
        case 1:
-           RExC_cpar++;
            ender = reganode(pRExC_state, CLOSE, parno);
            if (!SIZE_ONLY && RExC_seen & REG_SEEN_RECURSE) {
                DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
@@ -6003,15 +6246,26 @@ S_reg_recode(pTHX_ const char value, SV **encp)
 
 /*
  - regatom - the lowest level
- *
- * Optimization:  gobbles an entire sequence of ordinary characters so that
- * it can turn them into a single node, which is smaller to store and
- * faster to run.  Backslashed characters are exceptions, each becoming a
- * separate node; the code is simpler that way and it's not worth fixing.
- *
- * [Yes, it is worth fixing, some scripts can run twice the speed.]
- * [It looks like its ok, as in S_study_chunk we merge adjacent EXACT nodes]
- */
+
+   Try to identify anything special at the start of the pattern. If there
+   is, then handle it as required. This may involve generating a single regop,
+   such as for an assertion; or it may involve recursing, such as to
+   handle a () structure.
+
+   If the string doesn't start with something special then we gobble up
+   as much literal text as we can.
+
+   Once we have been able to handle whatever type of thing started the
+   sequence, we return.
+
+   Note: we have to be careful with escapes, as they can be both literal
+   and special, and in the case of \10 and friends can either, depending
+   on context. Specifically there are two seperate switches for handling
+   escape sequences, with the one for handling literal escapes requiring
+   a dummy entry for all of the special escapes that are actually handled
+   by the other.
+*/
+
 STATIC regnode *
 S_regatom(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
 {
@@ -6023,14 +6277,15 @@ S_regatom(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
     DEBUG_PARSE("atom");
     *flagp = WORST;            /* Tentatively. */
 
+
 tryagain:
     switch (*RExC_parse) {
     case '^':
        RExC_seen_zerolen++;
        nextchar(pRExC_state);
-       if (RExC_flags & PMf_MULTILINE)
+       if (RExC_flags & RXf_PMf_MULTILINE)
            ret = reg_node(pRExC_state, MBOL);
-       else if (RExC_flags & PMf_SINGLELINE)
+       else if (RExC_flags & RXf_PMf_SINGLELINE)
            ret = reg_node(pRExC_state, SBOL);
        else
            ret = reg_node(pRExC_state, BOL);
@@ -6040,9 +6295,9 @@ tryagain:
        nextchar(pRExC_state);
        if (*RExC_parse)
            RExC_seen_zerolen++;
-       if (RExC_flags & PMf_MULTILINE)
+       if (RExC_flags & RXf_PMf_MULTILINE)
            ret = reg_node(pRExC_state, MEOL);
-       else if (RExC_flags & PMf_SINGLELINE)
+       else if (RExC_flags & RXf_PMf_SINGLELINE)
            ret = reg_node(pRExC_state, SEOL);
        else
            ret = reg_node(pRExC_state, EOL);
@@ -6050,7 +6305,7 @@ tryagain:
        break;
     case '.':
        nextchar(pRExC_state);
-       if (RExC_flags & PMf_SINGLELINE)
+       if (RExC_flags & RXf_PMf_SINGLELINE)
            ret = reg_node(pRExC_state, SANY);
        else
            ret = reg_node(pRExC_state, REG_ANY);
@@ -6109,99 +6364,103 @@ tryagain:
        vFAIL("Quantifier follows nothing");
        break;
     case '\\':
+       /* Special Escapes
+
+          This switch handles escape sequences that resolve to some kind
+          of special regop and not to literal text. Escape sequnces that
+          resolve to literal text are handled below in the switch marked
+          "Literal Escapes".
+
+          Every entry in this switch *must* have a corresponding entry
+          in the literal escape switch. However, the opposite is not
+          required, as the default for this switch is to jump to the
+          literal text handling code.
+       */
        switch (*++RExC_parse) {
+       /* Special Escapes */
        case 'A':
            RExC_seen_zerolen++;
            ret = reg_node(pRExC_state, SBOL);
            *flagp |= SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'G':
            ret = reg_node(pRExC_state, GPOS);
            RExC_seen |= REG_SEEN_GPOS;
            *flagp |= SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
+       case 'K':
+           RExC_seen_zerolen++;
+           ret = reg_node(pRExC_state, KEEPS);
+           *flagp |= SIMPLE;
+           goto finish_meta_pat;
        case 'Z':
            ret = reg_node(pRExC_state, SEOL);
            *flagp |= SIMPLE;
            RExC_seen_zerolen++;                /* Do not optimize RE away */
-           nextchar(pRExC_state);
-           break;
+           goto finish_meta_pat;
        case 'z':
            ret = reg_node(pRExC_state, EOS);
            *flagp |= SIMPLE;
            RExC_seen_zerolen++;                /* Do not optimize RE away */
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'C':
            ret = reg_node(pRExC_state, CANY);
            RExC_seen |= REG_SEEN_CANY;
            *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'X':
            ret = reg_node(pRExC_state, CLUMP);
            *flagp |= HASWIDTH;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'w':
            ret = reg_node(pRExC_state, (U8)(LOC ? ALNUML     : ALNUM));
            *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'W':
            ret = reg_node(pRExC_state, (U8)(LOC ? NALNUML    : NALNUM));
-           *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           *flagp |= HASWIDTH|SIMPLE;
+           goto finish_meta_pat;
        case 'b':
            RExC_seen_zerolen++;
            RExC_seen |= REG_SEEN_LOOKBEHIND;
            ret = reg_node(pRExC_state, (U8)(LOC ? BOUNDL     : BOUND));
            *flagp |= SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'B':
            RExC_seen_zerolen++;
            RExC_seen |= REG_SEEN_LOOKBEHIND;
            ret = reg_node(pRExC_state, (U8)(LOC ? NBOUNDL    : NBOUND));
            *flagp |= SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 's':
            ret = reg_node(pRExC_state, (U8)(LOC ? SPACEL     : SPACE));
            *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'S':
            ret = reg_node(pRExC_state, (U8)(LOC ? NSPACEL    : NSPACE));
            *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'd':
            ret = reg_node(pRExC_state, DIGIT);
            *flagp |= HASWIDTH|SIMPLE;
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;
+           goto finish_meta_pat;
        case 'D':
            ret = reg_node(pRExC_state, NDIGIT);
            *flagp |= HASWIDTH|SIMPLE;
+           goto finish_meta_pat;
+       case 'v':
+           ret = reganode(pRExC_state, PRUNE, 0);
+           ret->flags = 1;
+           *flagp |= SIMPLE;
+           goto finish_meta_pat;
+       case 'V':
+           ret = reganode(pRExC_state, SKIP, 0);
+           ret->flags = 1;
+           *flagp |= SIMPLE;
+         finish_meta_pat:          
            nextchar(pRExC_state);
             Set_Node_Length(ret, 2); /* MJD */
-           break;
+           break;          
        case 'p':
        case 'P':
            {   
@@ -6246,86 +6505,88 @@ tryagain:
             ret= reg_namedseq(pRExC_state, NULL); 
             break;
        case 'k':    /* Handle \k<NAME> and \k'NAME' */
+       parse_named_seq:
         {   
             char ch= RExC_parse[1];        
-           if (ch != '<' && ch != '\'') {
-               if (SIZE_ONLY)
-                   vWARN( RExC_parse + 1, 
-                       "Possible broken named back reference treated as literal k");
-               parse_start--;
-               goto defchar;
+           if (ch != '<' && ch != '\'' && ch != '{') {
+               RExC_parse++;
+               vFAIL2("Sequence %.2s... not terminated",parse_start);
            } else {
+               /* this pretty much dupes the code for (?P=...) in reg(), if
+                   you change this make sure you change that */
                char* name_start = (RExC_parse += 2);
-               I32 num = 0;
+               U32 num = 0;
                 SV *sv_dat = reg_scan_name(pRExC_state,
                     SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                ch= (ch == '<') ? '>' : '\'';
-                    
+                ch= (ch == '<') ? '>' : (ch == '{') ? '}' : '\'';
                 if (RExC_parse == name_start || *RExC_parse != ch)
-                    vFAIL2("Sequence \\k%c... not terminated",
-                        (ch == '>' ? '<' : ch));
-                
+                    vFAIL2("Sequence %.3s... not terminated",parse_start);
+
+                if (!SIZE_ONLY) {
+                    num = add_data( pRExC_state, 1, "S" );
+                    RExC_rxi->data->data[num]=(void*)sv_dat;
+                    SvREFCNT_inc(sv_dat);
+                }
+
                 RExC_sawback = 1;
                 ret = reganode(pRExC_state,
                           (U8)(FOLD ? (LOC ? NREFFL : NREFF) : NREF),
                           num);
                 *flagp |= HASWIDTH;
-                
-               
-                if (!SIZE_ONLY) {
-                    num = add_data( pRExC_state, 1, "S" );
-                    ARG_SET(ret,num);
-                    RExC_rx->data->data[num]=(void*)sv_dat;
-                    SvREFCNT_inc(sv_dat);
-                }    
+
                 /* override incorrect value set in reganode MJD */
                 Set_Node_Offset(ret, parse_start+1);
                 Set_Node_Cur_Length(ret); /* MJD */
                 nextchar(pRExC_state);
-                              
+
             }
             break;
-        }            
-       case 'n':
-       case 'r':
-       case 't':
-       case 'f':
-       case 'e':
-       case 'a':
-       case 'x':
-       case 'c':
-       case '0':
-           goto defchar;
-       case 'R': 
+       }
+       case 'g': 
        case '1': case '2': case '3': case '4':
        case '5': case '6': case '7': case '8': case '9':
            {
                I32 num;
-               bool isrel=(*RExC_parse=='R');
-               if (isrel)
+               bool isg = *RExC_parse == 'g';
+               bool isrel = 0; 
+               bool hasbrace = 0;
+               if (isg) {
                    RExC_parse++;
+                   if (*RExC_parse == '{') {
+                       RExC_parse++;
+                       hasbrace = 1;
+                   }
+                   if (*RExC_parse == '-') {
+                       RExC_parse++;
+                       isrel = 1;
+                   }
+                   if (hasbrace && !isDIGIT(*RExC_parse)) {
+                       if (isrel) RExC_parse--;
+                        RExC_parse -= 2;                           
+                       goto parse_named_seq;
+               }   }
                num = atoi(RExC_parse);
                 if (isrel) {
-                    num = RExC_cpar - num;
+                    num = RExC_npar - num;
                     if (num < 1)
                         vFAIL("Reference to nonexistent or unclosed group");
                 }
-               if (num > 9 && num >= RExC_npar)
+               if (!isg && num > 9 && num >= RExC_npar)
                    goto defchar;
                else {
                    char * const parse_start = RExC_parse - 1; /* MJD */
                    while (isDIGIT(*RExC_parse))
                        RExC_parse++;
-
+                   if (parse_start == RExC_parse - 1) 
+                       vFAIL("Unterminated \\g... pattern");
+                    if (hasbrace) {
+                        if (*RExC_parse != '}') 
+                            vFAIL("Unterminated \\g{...} pattern");
+                        RExC_parse++;
+                    }    
                    if (!SIZE_ONLY) {
                        if (num > (I32)RExC_rx->nparens)
                            vFAIL("Reference to nonexistent group");
-                       /* People make this error all the time apparently.
-                          So we cant fail on it, even though we should 
-                       
-                       else if (num >= RExC_cpar)
-                           vFAIL("Reference to unclosed group will always match");
-                       */
                    }
                    RExC_sawback = 1;
                    ret = reganode(pRExC_state,
@@ -6354,7 +6615,7 @@ tryagain:
        break;
 
     case '#':
-       if (RExC_flags & PMf_EXTENDED) {
+       if (RExC_flags & RXf_PMf_EXTENDED) {
            while (RExC_parse < RExC_end && *RExC_parse != '\n')
                RExC_parse++;
            if (RExC_parse < RExC_end)
@@ -6385,7 +6646,7 @@ tryagain:
            {
                char * const oldp = p;
 
-               if (RExC_flags & PMf_EXTENDED)
+               if (RExC_flags & RXf_PMf_EXTENDED)
                    p = regwhite(p, RExC_end);
                switch (*p) {
                case '^':
@@ -6397,27 +6658,40 @@ tryagain:
                case '|':
                    goto loopdone;
                case '\\':
+                   /* Literal Escapes Switch
+
+                      This switch is meant to handle escape sequences that
+                      resolve to a literal character.
+
+                      Every escape sequence that represents something
+                      else, like an assertion or a char class, is handled
+                      in the switch marked 'Special Escapes' above in this
+                      routine, but also has an entry here as anything that
+                      isn't explicitly mentioned here will be treated as
+                      an unescaped equivalent literal.
+                   */
+
                    switch (*++p) {
-                   case 'A':
-                   case 'C':
-                   case 'X':
-                   case 'G':
-                   case 'Z':
-                   case 'z':
-                   case 'w':
-                   case 'W':
-                   case 'b':
-                   case 'B':
-                   case 's':
-                   case 'S':
-                   case 'd':
-                   case 'D':
-                   case 'p':
-                   case 'P':
-                    case 'N':
-                    case 'R':
+                   /* These are all the special escapes. */
+                   case 'A':             /* Start assertion */
+                   case 'b': case 'B':   /* Word-boundary assertion*/
+                   case 'C':             /* Single char !DANGEROUS! */
+                   case 'd': case 'D':   /* digit class */
+                   case 'g': case 'G':   /* generic-backref, pos assertion */
+                   case 'k': case 'K':   /* named backref, keep marker */
+                   case 'N':             /* named char sequence */
+                   case 'p': case 'P':   /* unicode property */
+                   case 's': case 'S':   /* space class */
+                   case 'v': case 'V':   /* (*PRUNE) and (*SKIP) */
+                   case 'w': case 'W':   /* word class */
+                   case 'X':             /* eXtended Unicode "combining character sequence" */
+                   case 'z': case 'Z':   /* End of line/string assertion */
                        --p;
                        goto loopdone;
+
+                   /* Anything after here is an escape that resolves to a
+                      literal. (Except digits, which may or may not)
+                    */
                    case 'n':
                        ender = '\n';
                        p++;
@@ -6521,7 +6795,7 @@ tryagain:
                        ender = *p++;
                    break;
                }
-               if (RExC_flags & PMf_EXTENDED)
+               if (RExC_flags & RXf_PMf_EXTENDED)
                    p = regwhite(p, RExC_end);
                if (UTF && FOLD) {
                    /* Prime the casefolded buffer. */
@@ -6800,11 +7074,38 @@ S_checkposixcc(pTHX_ RExC_state_t *pRExC_state)
 }
 
 
+#define _C_C_T_(NAME,TEST,WORD)                         \
+ANYOF_##NAME:                                           \
+    if (LOC)                                            \
+       ANYOF_CLASS_SET(ret, ANYOF_##NAME);             \
+    else {                                              \
+       for (value = 0; value < 256; value++)           \
+           if (TEST)                                   \
+               ANYOF_BITMAP_SET(ret, value);           \
+    }                                                   \
+    yesno = '+';                                        \
+    what = WORD;                                        \
+    break;                                              \
+case ANYOF_N##NAME:                                     \
+    if (LOC)                                            \
+       ANYOF_CLASS_SET(ret, ANYOF_N##NAME);            \
+    else {                                              \
+       for (value = 0; value < 256; value++)           \
+           if (!TEST)                                  \
+               ANYOF_BITMAP_SET(ret, value);           \
+    }                                                   \
+    yesno = '!';                                        \
+    what = WORD;                                        \
+    break
+
+
 /*
    parse a class specification and produce either an ANYOF node that
-   matches the pattern. If the pattern matches a single char only and
-   that char is < 256 then we produce an EXACT node instead.
+   matches the pattern or if the pattern matches a single char only and
+   that char is < 256 and we are case insensitive then we produce an 
+   EXACT node instead.
 */
+
 STATIC regnode *
 S_regclass(pTHX_ RExC_state_t *pRExC_state, U32 depth)
 {
@@ -7048,380 +7349,109 @@ parseit:
                    if (ckWARN(WARN_REGEXP)) {
                        const int w =
                            RExC_parse >= rangebegin ?
-                           RExC_parse - rangebegin : 0;
-                       vWARN4(RExC_parse,
-                              "False [] range \"%*.*s\"",
-                              w, w, rangebegin);
-                   }
-                   if (prevvalue < 256) {
-                       ANYOF_BITMAP_SET(ret, prevvalue);
-                       ANYOF_BITMAP_SET(ret, '-');
-                   }
-                   else {
-                       ANYOF_FLAGS(ret) |= ANYOF_UNICODE;
-                       Perl_sv_catpvf(aTHX_ listsv,
-                                      "%04"UVxf"\n%04"UVxf"\n", (UV)prevvalue, (UV) '-');
-                   }
-               }
-
-               range = 0; /* this was not a true range */
-           }
-
-           if (!SIZE_ONLY) {
-               const char *what = NULL;
-               char yesno = 0;
-
-               if (namedclass > OOB_NAMEDCLASS)
-                   optimize_invert = FALSE;
-               /* Possible truncation here but in some 64-bit environments
-                * the compiler gets heartburn about switch on 64-bit values.
-                * A similar issue a little earlier when switching on value.
-                * --jhi */
-               switch ((I32)namedclass) {
-               case ANYOF_ALNUM:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_ALNUM);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isALNUM(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Word";      
-                   break;
-               case ANYOF_NALNUM:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NALNUM);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isALNUM(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Word";
-                   break;
-               case ANYOF_ALNUMC:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_ALNUMC);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isALNUMC(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Alnum";
-                   break;
-               case ANYOF_NALNUMC:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NALNUMC);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isALNUMC(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Alnum";
-                   break;
-               case ANYOF_ALPHA:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_ALPHA);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isALPHA(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Alpha";
-                   break;
-               case ANYOF_NALPHA:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NALPHA);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isALPHA(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Alpha";
-                   break;
-               case ANYOF_ASCII:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_ASCII);
-                   else {
-#ifndef EBCDIC
-                       for (value = 0; value < 128; value++)
-                           ANYOF_BITMAP_SET(ret, value);
-#else  /* EBCDIC */
-                       for (value = 0; value < 256; value++) {
-                           if (isASCII(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                       }
-#endif /* EBCDIC */
-                   }
-                   yesno = '+';
-                   what = "ASCII";
-                   break;
-               case ANYOF_NASCII:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NASCII);
-                   else {
-#ifndef EBCDIC
-                       for (value = 128; value < 256; value++)
-                           ANYOF_BITMAP_SET(ret, value);
-#else  /* EBCDIC */
-                       for (value = 0; value < 256; value++) {
-                           if (!isASCII(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                       }
-#endif /* EBCDIC */
-                   }
-                   yesno = '!';
-                   what = "ASCII";
-                   break;
-               case ANYOF_BLANK:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_BLANK);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isBLANK(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Blank";
-                   break;
-               case ANYOF_NBLANK:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NBLANK);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isBLANK(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Blank";
-                   break;
-               case ANYOF_CNTRL:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_CNTRL);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isCNTRL(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Cntrl";
-                   break;
-               case ANYOF_NCNTRL:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NCNTRL);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isCNTRL(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Cntrl";
-                   break;
-               case ANYOF_DIGIT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_DIGIT);
-                   else {
-                       /* consecutive digits assumed */
-                       for (value = '0'; value <= '9'; value++)
-                           ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Digit";
-                   break;
-               case ANYOF_NDIGIT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NDIGIT);
-                   else {
-                       /* consecutive digits assumed */
-                       for (value = 0; value < '0'; value++)
-                           ANYOF_BITMAP_SET(ret, value);
-                       for (value = '9' + 1; value < 256; value++)
-                           ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Digit";
-                   break;
-               case ANYOF_GRAPH:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_GRAPH);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isGRAPH(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Graph";
-                   break;
-               case ANYOF_NGRAPH:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NGRAPH);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isGRAPH(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Graph";
-                   break;
-               case ANYOF_LOWER:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_LOWER);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isLOWER(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Lower";
-                   break;
-               case ANYOF_NLOWER:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NLOWER);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isLOWER(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Lower";
-                   break;
-               case ANYOF_PRINT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_PRINT);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isPRINT(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Print";
-                   break;
-               case ANYOF_NPRINT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NPRINT);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isPRINT(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Print";
-                   break;
-               case ANYOF_PSXSPC:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_PSXSPC);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isPSXSPC(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Space";
-                   break;
-               case ANYOF_NPSXSPC:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NPSXSPC);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isPSXSPC(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '!';
-                   what = "Space";
-                   break;
-               case ANYOF_PUNCT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_PUNCT);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isPUNCT(value))
-                               ANYOF_BITMAP_SET(ret, value);
-                   }
-                   yesno = '+';
-                   what = "Punct";
-                   break;
-               case ANYOF_NPUNCT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NPUNCT);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (!isPUNCT(value))
-                               ANYOF_BITMAP_SET(ret, value);
+                           RExC_parse - rangebegin : 0;
+                       vWARN4(RExC_parse,
+                              "False [] range \"%*.*s\"",
+                              w, w, rangebegin);
                    }
-                   yesno = '!';
-                   what = "Punct";
-                   break;
-               case ANYOF_SPACE:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_SPACE);
-                   else {
-                       for (value = 0; value < 256; value++)
-                           if (isSPACE(value))
-                               ANYOF_BITMAP_SET(ret, value);
+                   if (prevvalue < 256) {
+                       ANYOF_BITMAP_SET(ret, prevvalue);
+                       ANYOF_BITMAP_SET(ret, '-');
                    }
-                   yesno = '+';
-                   what = "SpacePerl";
-                   break;
-               case ANYOF_NSPACE:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NSPACE);
                    else {
-                       for (value = 0; value < 256; value++)
-                           if (!isSPACE(value))
-                               ANYOF_BITMAP_SET(ret, value);
+                       ANYOF_FLAGS(ret) |= ANYOF_UNICODE;
+                       Perl_sv_catpvf(aTHX_ listsv,
+                                      "%04"UVxf"\n%04"UVxf"\n", (UV)prevvalue, (UV) '-');
                    }
-                   yesno = '!';
-                   what = "SpacePerl";
-                   break;
-               case ANYOF_UPPER:
+               }
+
+               range = 0; /* this was not a true range */
+           }
+
+
+    
+           if (!SIZE_ONLY) {
+               const char *what = NULL;
+               char yesno = 0;
+
+               if (namedclass > OOB_NAMEDCLASS)
+                   optimize_invert = FALSE;
+               /* Possible truncation here but in some 64-bit environments
+                * the compiler gets heartburn about switch on 64-bit values.
+                * A similar issue a little earlier when switching on value.
+                * --jhi */
+               switch ((I32)namedclass) {
+               case _C_C_T_(ALNUM, isALNUM(value), "Word");
+               case _C_C_T_(ALNUMC, isALNUMC(value), "Alnum");
+               case _C_C_T_(ALPHA, isALPHA(value), "Alpha");
+               case _C_C_T_(BLANK, isBLANK(value), "Blank");
+               case _C_C_T_(CNTRL, isCNTRL(value), "Cntrl");
+               case _C_C_T_(GRAPH, isGRAPH(value), "Graph");
+               case _C_C_T_(LOWER, isLOWER(value), "Lower");
+               case _C_C_T_(PRINT, isPRINT(value), "Print");
+               case _C_C_T_(PSXSPC, isPSXSPC(value), "Space");
+               case _C_C_T_(PUNCT, isPUNCT(value), "Punct");
+               case _C_C_T_(SPACE, isSPACE(value), "SpacePerl");
+               case _C_C_T_(UPPER, isUPPER(value), "Upper");
+               case _C_C_T_(XDIGIT, isXDIGIT(value), "XDigit");
+               case ANYOF_ASCII:
                    if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_UPPER);
+                       ANYOF_CLASS_SET(ret, ANYOF_ASCII);
                    else {
-                       for (value = 0; value < 256; value++)
-                           if (isUPPER(value))
-                               ANYOF_BITMAP_SET(ret, value);
+#ifndef EBCDIC
+                       for (value = 0; value < 128; value++)
+                           ANYOF_BITMAP_SET(ret, value);
+#else  /* EBCDIC */
+                       for (value = 0; value < 256; value++) {
+                           if (isASCII(value))
+                               ANYOF_BITMAP_SET(ret, value);
+                       }
+#endif /* EBCDIC */
                    }
                    yesno = '+';
-                   what = "Upper";
+                   what = "ASCII";
                    break;
-               case ANYOF_NUPPER:
+               case ANYOF_NASCII:
                    if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NUPPER);
+                       ANYOF_CLASS_SET(ret, ANYOF_NASCII);
                    else {
-                       for (value = 0; value < 256; value++)
-                           if (!isUPPER(value))
-                               ANYOF_BITMAP_SET(ret, value);
+#ifndef EBCDIC
+                       for (value = 128; value < 256; value++)
+                           ANYOF_BITMAP_SET(ret, value);
+#else  /* EBCDIC */
+                       for (value = 0; value < 256; value++) {
+                           if (!isASCII(value))
+                               ANYOF_BITMAP_SET(ret, value);
+                       }
+#endif /* EBCDIC */
                    }
                    yesno = '!';
-                   what = "Upper";
-                   break;
-               case ANYOF_XDIGIT:
+                   what = "ASCII";
+                   break;              
+               case ANYOF_DIGIT:
                    if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_XDIGIT);
+                       ANYOF_CLASS_SET(ret, ANYOF_DIGIT);
                    else {
-                       for (value = 0; value < 256; value++)
-                           if (isXDIGIT(value))
-                               ANYOF_BITMAP_SET(ret, value);
+                       /* consecutive digits assumed */
+                       for (value = '0'; value <= '9'; value++)
+                           ANYOF_BITMAP_SET(ret, value);
                    }
                    yesno = '+';
-                   what = "XDigit";
+                   what = "Digit";
                    break;
-               case ANYOF_NXDIGIT:
+               case ANYOF_NDIGIT:
                    if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NXDIGIT);
+                       ANYOF_CLASS_SET(ret, ANYOF_NDIGIT);
                    else {
-                       for (value = 0; value < 256; value++)
-                           if (!isXDIGIT(value))
-                               ANYOF_BITMAP_SET(ret, value);
+                       /* consecutive digits assumed */
+                       for (value = 0; value < '0'; value++)
+                           ANYOF_BITMAP_SET(ret, value);
+                       for (value = '9' + 1; value < 256; value++)
+                           ANYOF_BITMAP_SET(ret, value);
                    }
                    yesno = '!';
-                   what = "XDigit";
-                   break;
+                   what = "Digit";
+                   break;              
                case ANYOF_MAX:
                    /* this is to handle \p and \P */
                    break;
@@ -7655,11 +7685,13 @@ parseit:
        av_store(av, 2, (SV*)unicode_alternate);
        rv = newRV_noinc((SV*)av);
        n = add_data(pRExC_state, 1, "s");
-       RExC_rx->data->data[n] = (void*)rv;
+       RExC_rxi->data->data[n] = (void*)rv;
        ARG_SET(ret, n);
     }
     return ret;
 }
+#undef _C_C_T_
+
 
 STATIC char*
 S_nextchar(pTHX_ RExC_state_t *pRExC_state)
@@ -7677,7 +7709,7 @@ S_nextchar(pTHX_ RExC_state_t *pRExC_state)
            RExC_parse++;
            continue;
        }
-       if (RExC_flags & PMf_EXTENDED) {
+       if (RExC_flags & RXf_PMf_EXTENDED) {
            if (isSPACE(*RExC_parse)) {
                RExC_parse++;
                continue;
@@ -7997,10 +8029,10 @@ S_regtail_study(pTHX_ RExC_state_t *pRExC_state, regnode *p, const regnode *val,
         SV * const mysv_val=sv_newmortal();
         DEBUG_PARSE_MSG("");
         regprop(RExC_rx, mysv_val, val);
-        PerlIO_printf(Perl_debug_log, "~ attach to %s (%d) offset to %d\n",
-            SvPV_nolen_const(mysv_val),
-            REG_NODE_NUM(val),
-            val - scan
+        PerlIO_printf(Perl_debug_log, "~ attach to %s (%"IVdf") offset to %"IVdf"\n",
+                     SvPV_nolen_const(mysv_val),
+                     (IV)REG_NODE_NUM(val),
+                     (IV)(val - scan)
         );
     });
     if (reg_off_by_arg[OP(scan)]) {
@@ -8046,8 +8078,9 @@ Perl_regdump(pTHX_ const regexp *r)
     dVAR;
     SV * const sv = sv_newmortal();
     SV *dsv= sv_newmortal();
+    RXi_GET_DECL(r,ri);
 
-    (void)dumpuntil(r, r->program, r->program + 1, NULL, NULL, sv, 0, 0);
+    (void)dumpuntil(r, ri->program, ri->program + 1, NULL, NULL, sv, 0, 0);
 
     /* Header fields of interest. */
     if (r->anchored_substr) {
@@ -8086,37 +8119,37 @@ Perl_regdump(pTHX_ const regexp *r)
                      (r->check_substr == r->float_substr
                       && r->check_utf8 == r->float_utf8
                       ? "(checking floating" : "(checking anchored"));
-    if (r->reganch & ROPT_NOSCAN)
+    if (r->extflags & RXf_NOSCAN)
        PerlIO_printf(Perl_debug_log, " noscan");
-    if (r->reganch & ROPT_CHECK_ALL)
+    if (r->extflags & RXf_CHECK_ALL)
        PerlIO_printf(Perl_debug_log, " isall");
     if (r->check_substr || r->check_utf8)
        PerlIO_printf(Perl_debug_log, ") ");
 
-    if (r->regstclass) {
-       regprop(r, sv, r->regstclass);
+    if (ri->regstclass) {
+       regprop(r, sv, ri->regstclass);
        PerlIO_printf(Perl_debug_log, "stclass %s ", SvPVX_const(sv));
     }
-    if (r->reganch & ROPT_ANCH) {
+    if (r->extflags & RXf_ANCH) {
        PerlIO_printf(Perl_debug_log, "anchored");
-       if (r->reganch & ROPT_ANCH_BOL)
+       if (r->extflags & RXf_ANCH_BOL)
            PerlIO_printf(Perl_debug_log, "(BOL)");
-       if (r->reganch & ROPT_ANCH_MBOL)
+       if (r->extflags & RXf_ANCH_MBOL)
            PerlIO_printf(Perl_debug_log, "(MBOL)");
-       if (r->reganch & ROPT_ANCH_SBOL)
+       if (r->extflags & RXf_ANCH_SBOL)
            PerlIO_printf(Perl_debug_log, "(SBOL)");
-       if (r->reganch & ROPT_ANCH_GPOS)
+       if (r->extflags & RXf_ANCH_GPOS)
            PerlIO_printf(Perl_debug_log, "(GPOS)");
        PerlIO_putc(Perl_debug_log, ' ');
     }
-    if (r->reganch & ROPT_GPOS_SEEN)
-       PerlIO_printf(Perl_debug_log, "GPOS ");
-    if (r->reganch & ROPT_SKIP)
+    if (r->extflags & RXf_GPOS_SEEN)
+       PerlIO_printf(Perl_debug_log, "GPOS:%"UVuf" ", (UV)r->gofs);
+    if (r->intflags & PREGf_SKIP)
        PerlIO_printf(Perl_debug_log, "plus ");
-    if (r->reganch & ROPT_IMPLICIT)
+    if (r->intflags & PREGf_IMPLICIT)
        PerlIO_printf(Perl_debug_log, "implicit ");
-    PerlIO_printf(Perl_debug_log, "minlen %ld ", (long) r->minlen);
-    if (r->reganch & ROPT_EVAL_SEEN)
+    PerlIO_printf(Perl_debug_log, "minlen %"IVdf" ", (IV)r->minlen);
+    if (r->extflags & RXf_EVAL_SEEN)
        PerlIO_printf(Perl_debug_log, "with eval ");
     PerlIO_printf(Perl_debug_log, "\n");
 #else
@@ -8134,10 +8167,12 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
 #ifdef DEBUGGING
     dVAR;
     register int k;
+    RXi_GET_DECL(prog,progi);
     GET_RE_DEBUG_FLAGS_DECL;
+    
 
     sv_setpvn(sv, "", 0);
-    
+
     if (OP(o) > REGNODE_MAX)           /* regnode.type is unsigned */
        /* It would be nice to FAIL() here, but this may be called from
           regexec.c, and it would be hard to supply pRExC_state. */
@@ -8162,15 +8197,14 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
        Perl_sv_catpvf(aTHX_ sv, " %s", s );
     } else if (k == TRIE) {
        /* print the details of the trie in dumpuntil instead, as
-        * prog->data isn't available here */
+        * progi->data isn't available here */
         const char op = OP(o);
-        const I32 n = ARG(o);
+        const U32 n = ARG(o);
         const reg_ac_data * const ac = IS_TRIE_AC(op) ?
-               (reg_ac_data *)prog->data->data[n] :
+               (reg_ac_data *)progi->data->data[n] :
                NULL;
-        const reg_trie_data * const trie = !IS_TRIE_AC(op) ?
-            (reg_trie_data*)prog->data->data[n] :
-            ac->trie;
+        const reg_trie_data * const trie
+           = (reg_trie_data*)progi->data->data[!IS_TRIE_AC(op) ? n : ac->trie];
         
         Perl_sv_catpvf(aTHX_ sv, "-%s",reg_name[o->flags]);
         DEBUG_TRIE_COMPILE_r(
@@ -8216,14 +8250,36 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
     }
     else if (k == WHILEM && o->flags)                  /* Ordinal/of */
        Perl_sv_catpvf(aTHX_ sv, "[%d/%d]", o->flags & 0xf, o->flags>>4);
-    else if (k == REF || k == OPEN || k == CLOSE || k == GROUPP || OP(o)==ACCEPT) 
+    else if (k == REF || k == OPEN || k == CLOSE || k == GROUPP || OP(o)==ACCEPT) {
        Perl_sv_catpvf(aTHX_ sv, "%d", (int)ARG(o));    /* Parenth number */
-    else if (k == GOSUB) 
+       if ( prog->paren_names ) {
+            if ( k != REF || OP(o) < NREF) {       
+               AV *list= (AV *)progi->data->data[progi->name_list_idx];
+               SV **name= av_fetch(list, ARG(o), 0 );
+               if (name)
+                   Perl_sv_catpvf(aTHX_ sv, " '%"SVf"'", SVfARG(*name));
+            }      
+            else {
+                AV *list= (AV *)progi->data->data[ progi->name_list_idx ];
+                SV *sv_dat=(SV*)progi->data->data[ ARG( o ) ];
+                I32 *nums=(I32*)SvPVX(sv_dat);
+                SV **name= av_fetch(list, nums[0], 0 );
+                I32 n;
+                if (name) {
+                    for ( n=0; n<SvIVX(sv_dat); n++ ) {
+                        Perl_sv_catpvf(aTHX_ sv, "%s%"IVdf,
+                                   (n ? "," : ""), (IV)nums[n]);
+                    }
+                    Perl_sv_catpvf(aTHX_ sv, " '%"SVf"'", SVfARG(*name));
+                }
+            }
+        }            
+    } else if (k == GOSUB) 
        Perl_sv_catpvf(aTHX_ sv, "%d[%+d]", (int)ARG(o),(int)ARG2L(o)); /* Paren and offset */
     else if (k == VERB) {
         if (!o->flags) 
             Perl_sv_catpvf(aTHX_ sv, ":%"SVf, 
-                (SV*)prog->data->data[ ARG( o ) ]);
+                SVfARG((SV*)progi->data->data[ ARG( o ) ]));
     } else if (k == LOGICAL)
        Perl_sv_catpvf(aTHX_ sv, "[%d]", o->flags);     /* 2: embedded, otherwise 1 */
     else if (k == ANYOF) {
@@ -8402,36 +8458,32 @@ Perl_re_intuit_string(pTHX_ regexp *prog)
 }
 
 /* 
-   pregfree - free a regexp
+   pregfree() 
    
-   See regdupe below if you change anything here. 
+   handles refcounting and freeing the perl core regexp structure. When 
+   it is necessary to actually free the structure the first thing it 
+   does is call the 'free' method of the regexp_engine associated to to 
+   the regexp, allowing the handling of the void *pprivate; member 
+   first. (This routine is not overridable by extensions, which is why 
+   the extensions free is called first.)
+   
+   See regdupe and regdupe_internal if you change anything here. 
 */
-
+#ifndef PERL_IN_XSUB_RE
 void
 Perl_pregfree(pTHX_ struct regexp *r)
 {
     dVAR;
-
     GET_RE_DEBUG_FLAGS_DECL;
 
     if (!r || (--r->refcnt > 0))
        return;
-    DEBUG_COMPILE_r({
-       if (!PL_colorset)
-           reginitcolors();
-       {
-           SV *dsv= sv_newmortal();
-            RE_PV_QUOTED_DECL(s, (r->reganch & ROPT_UTF8),
-                dsv, r->precomp, r->prelen, 60);
-            PerlIO_printf(Perl_debug_log,"%sFreeing REx:%s %s\n", 
-                PL_colors[4],PL_colors[5],s);
-        }
-    });
-
+       
+    CALLREGFREE_PVT(r); /* free the private data */
+    
     /* gcov results gave these as non-null 100% of the time, so there's no
        optimisation in checking them before calling Safefree  */
     Safefree(r->precomp);
-    Safefree(r->offsets);             /* 20010421 MJD */
     RX_MATCH_COPY_FREE(r);
 #ifdef PERL_OLD_COPY_ON_WRITE
     if (r->saved_copy)
@@ -8450,24 +8502,64 @@ Perl_pregfree(pTHX_ struct regexp *r)
     }
     if (r->paren_names)
             SvREFCNT_dec(r->paren_names);
-    if (r->data) {
-       int n = r->data->count;
+    
+    Safefree(r->startp);
+    Safefree(r->endp);
+    Safefree(r);
+}
+#endif
+
+/* regfree_internal() 
+
+   Free the private data in a regexp. This is overloadable by 
+   extensions. Perl takes care of the regexp structure in pregfree(), 
+   this covers the *pprivate pointer which technically perldoesnt 
+   know about, however of course we have to handle the 
+   regexp_internal structure when no extension is in use. 
+   
+   Note this is called before freeing anything in the regexp 
+   structure. 
+ */
+void
+Perl_regfree_internal(pTHX_ struct regexp *r)
+{
+    dVAR;
+    RXi_GET_DECL(r,ri);
+    GET_RE_DEBUG_FLAGS_DECL;
+    
+    DEBUG_COMPILE_r({
+       if (!PL_colorset)
+           reginitcolors();
+       {
+           SV *dsv= sv_newmortal();
+            RE_PV_QUOTED_DECL(s, (r->extflags & RXf_UTF8),
+                dsv, r->precomp, r->prelen, 60);
+            PerlIO_printf(Perl_debug_log,"%sFreeing REx:%s %s\n", 
+                PL_colors[4],PL_colors[5],s);
+        }
+    });
+
+    Safefree(ri->offsets);             /* 20010421 MJD */
+    if (ri->data) {
+       int n = ri->data->count;
        PAD* new_comppad = NULL;
        PAD* old_comppad;
        PADOFFSET refcnt;
 
        while (--n >= 0) {
           /* If you add a ->what type here, update the comment in regcomp.h */
-           switch (r->data->what[n]) {
+           switch (ri->data->what[n]) {
            case 's':
            case 'S':
-               SvREFCNT_dec((SV*)r->data->data[n]);
+           case 'u':
+               SvREFCNT_dec((SV*)ri->data->data[n]);
                break;
            case 'f':
-               Safefree(r->data->data[n]);
+               Safefree(ri->data->data[n]);
                break;
            case 'p':
-               new_comppad = (AV*)r->data->data[n];
+               new_comppad = (AV*)ri->data->data[n];
                break;
            case 'o':
                if (new_comppad == NULL)
@@ -8477,10 +8569,10 @@ Perl_pregfree(pTHX_ struct regexp *r)
                    (SvTYPE(new_comppad) == SVt_PVAV) ? new_comppad : NULL
                );
                OP_REFCNT_LOCK;
-               refcnt = OpREFCNT_dec((OP_4tree*)r->data->data[n]);
+               refcnt = OpREFCNT_dec((OP_4tree*)ri->data->data[n]);
                OP_REFCNT_UNLOCK;
                if (!refcnt)
-                    op_free((OP_4tree*)r->data->data[n]);
+                    op_free((OP_4tree*)ri->data->data[n]);
 
                PAD_RESTORE_LOCAL(old_comppad);
                SvREFCNT_dec((SV*)new_comppad);
@@ -8492,17 +8584,16 @@ Perl_pregfree(pTHX_ struct regexp *r)
                 { /* Aho Corasick add-on structure for a trie node.
                      Used in stclass optimization only */
                     U32 refcount;
-                    reg_ac_data *aho=(reg_ac_data*)r->data->data[n];
+                    reg_ac_data *aho=(reg_ac_data*)ri->data->data[n];
                     OP_REFCNT_LOCK;
                     refcount = --aho->refcount;
                     OP_REFCNT_UNLOCK;
                     if ( !refcount ) {
-                        Safefree(aho->states);
-                        Safefree(aho->fail);
-                        aho->trie=NULL; /* not necessary to free this as it is 
-                                           handled by the 't' case */
-                        Safefree(r->data->data[n]); /* do this last!!!! */
-                        Safefree(r->regstclass);
+                        PerlMemShared_free(aho->states);
+                        PerlMemShared_free(aho->fail);
+                        /* do this last!!!! */
+                        PerlMemShared_free(ri->data->data[n]);
+                        PerlMemShared_free(ri->regstclass);
                     }
                 }
                 break;
@@ -8510,49 +8601,40 @@ Perl_pregfree(pTHX_ struct regexp *r)
                {
                    /* trie structure. */
                    U32 refcount;
-                   reg_trie_data *trie=(reg_trie_data*)r->data->data[n];
+                   reg_trie_data *trie=(reg_trie_data*)ri->data->data[n];
                     OP_REFCNT_LOCK;
                     refcount = --trie->refcount;
                     OP_REFCNT_UNLOCK;
                     if ( !refcount ) {
-                        Safefree(trie->charmap);
-                        if (trie->widecharmap)
-                            SvREFCNT_dec((SV*)trie->widecharmap);
-                        Safefree(trie->states);
-                        Safefree(trie->trans);
+                        PerlMemShared_free(trie->charmap);
+                        PerlMemShared_free(trie->states);
+                        PerlMemShared_free(trie->trans);
                         if (trie->bitmap)
-                            Safefree(trie->bitmap);
+                            PerlMemShared_free(trie->bitmap);
                         if (trie->wordlen)
-                            Safefree(trie->wordlen);
+                            PerlMemShared_free(trie->wordlen);
                         if (trie->jump)
-                            Safefree(trie->jump);
+                            PerlMemShared_free(trie->jump);
                         if (trie->nextword)
-                            Safefree(trie->nextword);
-#ifdef DEBUGGING
-                        if (trie->words)
-                            SvREFCNT_dec((SV*)trie->words);
-                        if (trie->revcharmap)
-                            SvREFCNT_dec((SV*)trie->revcharmap);
-#endif
-                        Safefree(r->data->data[n]); /* do this last!!!! */
+                            PerlMemShared_free(trie->nextword);
+                        /* do this last!!!! */
+                        PerlMemShared_free(ri->data->data[n]);
                    }
                }
                break;
            default:
-               Perl_croak(aTHX_ "panic: regfree data code '%c'", r->data->what[n]);
+               Perl_croak(aTHX_ "panic: regfree data code '%c'", ri->data->what[n]);
            }
        }
-       Safefree(r->data->what);
-       Safefree(r->data);
+       Safefree(ri->data->what);
+       Safefree(ri->data);
     }
-    Safefree(r->startp);
-    Safefree(r->endp);
-    if (r->swap) {
-        Safefree(r->swap->startp);
-        Safefree(r->swap->endp);
-        Safefree(r->swap);
+    if (ri->swap) {
+        Safefree(ri->swap->startp);
+        Safefree(ri->swap->endp);
+        Safefree(ri->swap);
     }
-    Safefree(r);
+    Safefree(ri);
 }
 
 #define sv_dup_inc(s,t)        SvREFCNT_inc(sv_dup(s,t))
@@ -8567,15 +8649,21 @@ Perl_pregfree(pTHX_ struct regexp *r)
    given regexp structure. It is a no-op when not under USE_ITHREADS. 
    (Originally this *was* re_dup() for change history see sv.c)
    
-   See pregfree() above if you change anything here. 
+   After all of the core data stored in struct regexp is duplicated
+   the regexp_engine.dupe method is used to copy any private data
+   stored in the *pprivate pointer. This allows extensions to handle
+   any duplication it needs to do.
+
+   See pregfree() and regfree_internal() if you change anything here. 
 */
 #if defined(USE_ITHREADS)
+#ifndef PERL_IN_XSUB_RE
 regexp *
-Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
+Perl_re_dup(pTHX_ const regexp *r, CLONE_PARAMS *param)
 {
     dVAR;
-    REGEXP *ret;
-    int i, len, npar;
+    regexp *ret;
+    int i, npar;
     struct reg_substr_datum *s;
 
     if (!r)
@@ -8584,38 +8672,102 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
     if ((ret = (REGEXP *)ptr_table_fetch(PL_ptr_table, r)))
        return ret;
 
-    len = r->offsets[0];
+    
     npar = r->nparens+1;
-
-    Newxc(ret, sizeof(regexp) + (len+1)*sizeof(regnode), char, regexp);
-    Copy(r->program, ret->program, len+1, regnode);
-
+    Newxz(ret, 1, regexp);
     Newx(ret->startp, npar, I32);
     Copy(r->startp, ret->startp, npar, I32);
     Newx(ret->endp, npar, I32);
-    Copy(r->startp, ret->startp, npar, I32);
-    if(r->swap) {
-        Newx(ret->swap, 1, regexp_paren_ofs);
+    Copy(r->endp, ret->endp, npar, I32);
+
+    if (r->substrs) {
+        Newx(ret->substrs, 1, struct reg_substr_data);
+        for (s = ret->substrs->data, i = 0; i < 3; i++, s++) {
+            s->min_offset = r->substrs->data[i].min_offset;
+            s->max_offset = r->substrs->data[i].max_offset;
+            s->end_shift  = r->substrs->data[i].end_shift;
+            s->substr     = sv_dup_inc(r->substrs->data[i].substr, param);
+            s->utf8_substr = sv_dup_inc(r->substrs->data[i].utf8_substr, param);
+        }
+    } else 
+        ret->substrs = NULL;    
+
+    ret->precomp        = SAVEPVN(r->precomp, r->prelen);
+    ret->refcnt         = r->refcnt;
+    ret->minlen         = r->minlen;
+    ret->minlenret      = r->minlenret;
+    ret->prelen         = r->prelen;
+    ret->nparens        = r->nparens;
+    ret->lastparen      = r->lastparen;
+    ret->lastcloseparen = r->lastcloseparen;
+    ret->intflags       = r->intflags;
+    ret->extflags       = r->extflags;
+
+    ret->sublen         = r->sublen;
+
+    ret->engine         = r->engine;
+    
+    ret->paren_names    = hv_dup_inc(r->paren_names, param);
+
+    if (RX_MATCH_COPIED(ret))
+       ret->subbeg  = SAVEPVN(r->subbeg, r->sublen);
+    else
+       ret->subbeg = NULL;
+#ifdef PERL_OLD_COPY_ON_WRITE
+    ret->saved_copy = NULL;
+#endif
+    
+    ret->pprivate = r->pprivate;
+    if (ret->pprivate) 
+        RXi_SET(ret,CALLREGDUPE_PVT(ret,param));
+    
+    ptr_table_store(PL_ptr_table, r, ret);
+    return ret;
+}
+#endif /* PERL_IN_XSUB_RE */
+
+/*
+   regdupe_internal()
+   
+   This is the internal complement to regdupe() which is used to copy
+   the structure pointed to by the *pprivate pointer in the regexp.
+   This is the core version of the extension overridable cloning hook.
+   The regexp structure being duplicated will be copied by perl prior
+   to this and will be provided as the regexp *r argument, however 
+   with the /old/ structures pprivate pointer value. Thus this routine
+   may override any copying normally done by perl.
+   
+   It returns a pointer to the new regexp_internal structure.
+*/
+
+void *
+Perl_regdupe_internal(pTHX_ const regexp *r, CLONE_PARAMS *param)
+{
+    dVAR;
+    regexp_internal *reti;
+    int len, npar;
+    RXi_GET_DECL(r,ri);
+    
+    npar = r->nparens+1;
+    len = ri->offsets[0];
+    
+    Newxc(reti, sizeof(regexp_internal) + (len+1)*sizeof(regnode), char, regexp_internal);
+    Copy(ri->program, reti->program, len+1, regnode);
+    
+    if(ri->swap) {
+        Newx(reti->swap, 1, regexp_paren_ofs);
         /* no need to copy these */
-        Newx(ret->swap->startp, npar, I32);
-        Newx(ret->swap->endp, npar, I32);
+        Newx(reti->swap->startp, npar, I32);
+        Newx(reti->swap->endp, npar, I32);
     } else {
-        ret->swap = NULL;
+        reti->swap = NULL;
     }
 
-    Newx(ret->substrs, 1, struct reg_substr_data);
-    for (s = ret->substrs->data, i = 0; i < 3; i++, s++) {
-       s->min_offset = r->substrs->data[i].min_offset;
-       s->max_offset = r->substrs->data[i].max_offset;
-       s->end_shift  = r->substrs->data[i].end_shift;
-       s->substr     = sv_dup_inc(r->substrs->data[i].substr, param);
-       s->utf8_substr = sv_dup_inc(r->substrs->data[i].utf8_substr, param);
-    }
 
-    ret->regstclass = NULL;
-    if (r->data) {
+    reti->regstclass = NULL;
+    if (ri->data) {
        struct reg_data *d;
-        const int count = r->data->count;
+        const int count = ri->data->count;
        int i;
 
        Newxc(d, sizeof(struct reg_data) + count*sizeof(void *),
@@ -8624,92 +8776,64 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
 
        d->count = count;
        for (i = 0; i < count; i++) {
-           d->what[i] = r->data->what[i];
+           d->what[i] = ri->data->what[i];
            switch (d->what[i]) {
-               /* legal options are one of: sSfpont
+               /* legal options are one of: sSfpontTu
                   see also regcomp.h and pregfree() */
            case 's':
            case 'S':
-               d->data[i] = sv_dup_inc((SV *)r->data->data[i], param);
-               break;
-           case 'p':
-               d->data[i] = av_dup_inc((AV *)r->data->data[i], param);
+           case 'p': /* actually an AV, but the dup function is identical.  */
+           case 'u': /* actually an HV, but the dup function is identical.  */
+               d->data[i] = sv_dup_inc((SV *)ri->data->data[i], param);
                break;
            case 'f':
                /* This is cheating. */
                Newx(d->data[i], 1, struct regnode_charclass_class);
-               StructCopy(r->data->data[i], d->data[i],
+               StructCopy(ri->data->data[i], d->data[i],
                            struct regnode_charclass_class);
-               ret->regstclass = (regnode*)d->data[i];
+               reti->regstclass = (regnode*)d->data[i];
                break;
            case 'o':
-               /* Compiled op trees are readonly, and can thus be
-                  shared without duplication. */
-               OP_REFCNT_LOCK;
-               d->data[i] = (void*)OpREFCNT_inc((OP*)r->data->data[i]);
-               OP_REFCNT_UNLOCK;
-               break;
-           case 'n':
-               d->data[i] = r->data->data[i];
-               break;
-           case 't':
-               d->data[i] = r->data->data[i];
+               /* Compiled op trees are readonly and in shared memory,
+                  and can thus be shared without duplication. */
                OP_REFCNT_LOCK;
-               ((reg_trie_data*)d->data[i])->refcount++;
+               d->data[i] = (void*)OpREFCNT_inc((OP*)ri->data->data[i]);
                OP_REFCNT_UNLOCK;
                break;
            case 'T':
-               d->data[i] = r->data->data[i];
-               OP_REFCNT_LOCK;
-               ((reg_ac_data*)d->data[i])->refcount++;
-               OP_REFCNT_UNLOCK;
                /* Trie stclasses are readonly and can thus be shared
                 * without duplication. We free the stclass in pregfree
                 * when the corresponding reg_ac_data struct is freed.
                 */
-               ret->regstclass= r->regstclass;
+               reti->regstclass= ri->regstclass;
+               /* Fall through */
+           case 't':
+               OP_REFCNT_LOCK;
+               ((reg_trie_data*)ri->data->data[i])->refcount++;
+               OP_REFCNT_UNLOCK;
+               /* Fall through */
+           case 'n':
+               d->data[i] = ri->data->data[i];
                break;
             default:
-               Perl_croak(aTHX_ "panic: re_dup unknown data code '%c'", r->data->what[i]);
+               Perl_croak(aTHX_ "panic: re_dup unknown data code '%c'", ri->data->what[i]);
            }
        }
 
-       ret->data = d;
+       reti->data = d;
     }
     else
-       ret->data = NULL;
-
-    Newx(ret->offsets, 2*len+1, U32);
-    Copy(r->offsets, ret->offsets, 2*len+1, U32);
-
-    ret->precomp        = SAVEPVN(r->precomp, r->prelen);
-    ret->refcnt         = r->refcnt;
-    ret->minlen         = r->minlen;
-    ret->minlenret      = r->minlenret;
-    ret->prelen         = r->prelen;
-    ret->nparens        = r->nparens;
-    ret->lastparen      = r->lastparen;
-    ret->lastcloseparen = r->lastcloseparen;
-    ret->reganch        = r->reganch;
+       reti->data = NULL;
 
-    ret->sublen         = r->sublen;
+    reti->name_list_idx = ri->name_list_idx;
 
-    ret->engine         = r->engine;
+    Newx(reti->offsets, 2*len+1, U32);
+    Copy(ri->offsets, reti->offsets, 2*len+1, U32);
     
-    ret->paren_names    = hv_dup_inc(r->paren_names, param);
-
-    if (RX_MATCH_COPIED(ret))
-       ret->subbeg  = SAVEPVN(r->subbeg, r->sublen);
-    else
-       ret->subbeg = NULL;
-#ifdef PERL_OLD_COPY_ON_WRITE
-    ret->saved_copy = NULL;
-#endif
-
-    ptr_table_store(PL_ptr_table, r, ret);
-    return ret;
+    return (void*)reti;
 }
-#endif    
+
+#endif    /* USE_ITHREADS */
 
 /* 
    reg_stringify() 
@@ -8722,37 +8846,40 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
    resulting string
    
    If flags is nonnull and the returned string contains UTF8 then 
-   (flags & 1) will be true.
+   (*flags & 1) will be true.
    
    If haseval is nonnull then it is used to return whether the pattern 
    contains evals.
    
    Normally called via macro: 
    
-        CALLREG_STRINGIFY(mg,0,0);
+        CALLREG_STRINGIFY(mg,&len,&utf8);
         
    And internally with
    
-        CALLREG_AS_STR(mg,lp,flags,haseval)        
+        CALLREG_AS_STR(mg,&lp,&flags,&haseval)        
     
    See sv_2pv_flags() in sv.c for an example of internal usage.
     
  */
-
+#ifndef PERL_IN_XSUB_RE
 char *
 Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
     dVAR;
     const regexp * const re = (regexp *)mg->mg_obj;
 
     if (!mg->mg_ptr) {
-       const char *fptr = "msix";
-       char reflags[6];
+       const char *fptr = STD_PAT_MODS;        /*"msix"*/
+       char reflags[7];
        char ch;
-       int left = 0;
-       int right = 4;
-       bool need_newline = 0;
-       U16 reganch = (U16)((re->reganch & PMf_COMPILETIME) >> 12);
-
+       bool hask = ((re->extflags & RXf_PMf_KEEPCOPY) == RXf_PMf_KEEPCOPY);
+       bool hasm = ((re->extflags & RXf_PMf_STD_PMMOD) != RXf_PMf_STD_PMMOD);
+        U16 reganch = (U16)((re->extflags & RXf_PMf_STD_PMMOD) >> 12);
+        bool need_newline = 0;
+        int left = 0;
+       int right = 4 + hask;
+        if (hask) 
+            reflags[left++] = KEEPCOPY_PAT_MOD; /*'k'*/
        while((ch = *fptr++)) {
            if(reganch & 1) {
                reflags[left++] = ch;
@@ -8762,11 +8889,11 @@ Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
            }
            reganch >>= 1;
        }
-       if(left != 4) {
+       if(hasm) {
            reflags[left] = '-';
-           left = 5;
+           left = 5 + hask;
        }
-
+        /* printf("[%*.7s]\n",left,reflags); */
        mg->mg_len = re->prelen + 4 + left;
        /*
         * If /x was used, we have to worry about a regex ending with a
@@ -8779,7 +8906,7 @@ Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
         * ourself. If we find a '\n' first (or if we don't find '#' or '\n'),
         * we don't need to add anything.  -jfriedl
         */
-       if (PMf_EXTENDED & re->reganch) {
+       if (PMf_EXTENDED & re->extflags) {
            const char *endptr = re->precomp + re->prelen;
            while (endptr >= re->precomp) {
                const char c = *(endptr--);
@@ -8806,17 +8933,15 @@ Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
        mg->mg_ptr[mg->mg_len] = 0;
     }
     if (haseval) 
-        *haseval = re->program[0].next_off;
+        *haseval = re->seen_evals;
     if (flags)    
-       *flags = ((re->reganch & ROPT_UTF8) ? 1 : 0);
+       *flags = ((re->extflags & RXf_UTF8) ? 1 : 0);
     
     if (lp)
        *lp = mg->mg_len;
     return mg->mg_ptr;
 }
 
-
-#ifndef PERL_IN_XSUB_RE
 /*
  - regnext - dig the "next" pointer out of a node
  */
@@ -8826,7 +8951,7 @@ Perl_regnext(pTHX_ register regnode *p)
     dVAR;
     register I32 offset;
 
-    if (p == &PL_regdummy)
+    if (!p)
        return(NULL);
 
     offset = (reg_off_by_arg[OP(p)] ? ARG(p) : NEXT_OFF(p));
@@ -8947,7 +9072,7 @@ S_put_byte(pTHX_ SV *sv, int c)
 
 #define CLEAR_OPTSTART \
     if (optstart) STMT_START { \
-           DEBUG_OPTIMISE_r(PerlIO_printf(Perl_debug_log, " (%d nodes)\n", node - optstart)); \
+           DEBUG_OPTIMISE_r(PerlIO_printf(Perl_debug_log, " (%"IVdf" nodes)\n", (IV)(node - optstart))); \
            optstart=NULL; \
     } STMT_END
 
@@ -8962,8 +9087,10 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
     register U8 op = PSEUDO;   /* Arbitrary non-END op. */
     register const regnode *next;
     const regnode *optstart= NULL;
+    
+    RXi_GET_DECL(r,ri);
     GET_RE_DEBUG_FLAGS_DECL;
-
+    
 #ifdef DEBUG_DUMPUNTIL
     PerlIO_printf(Perl_debug_log, "--- %d : %d - %d - %d\n",indent,node-start,
         last ? last-start : 0,plast ? plast-start : 0);
@@ -8974,13 +9101,12 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
 
     while (PL_regkind[op] != END && (!last || node < last)) {
        /* While that wasn't END last time... */
-
        NODE_ALIGN(node);
        op = OP(node);
-       if (op == CLOSE)
+       if (op == CLOSE || op == WHILEM)
            indent--;
        next = regnext((regnode *)node);
-       
+
        /* Where, what. */
        if (OP(node) == OPTIMIZED) {
            if (!optstart && RE_DEBUG_FLAG(RE_DEBUG_COMPILE_OPTIMISE))
@@ -8989,23 +9115,21 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
                goto after_print;
        } else
            CLEAR_OPTSTART;
-           
+       
        regprop(r, sv, node);
        PerlIO_printf(Perl_debug_log, "%4"IVdf":%*s%s", (IV)(node - start),
                      (int)(2*indent + 1), "", SvPVX_const(sv));
-
-       if (OP(node) != OPTIMIZED) {
-           if (next == NULL)           /* Next ptr. */
-               PerlIO_printf(Perl_debug_log, "(0)");
-           else if (PL_regkind[(U8)op] == BRANCH && PL_regkind[OP(next)] != BRANCH )
-               PerlIO_printf(Perl_debug_log, "(FAIL)");
-           else
-               PerlIO_printf(Perl_debug_log, "(%"IVdf")", (IV)(next - start));
-               
-           /*if (PL_regkind[(U8)op]  != TRIE)*/
-               (void)PerlIO_putc(Perl_debug_log, '\n');
-       }
-
+        
+        if (OP(node) != OPTIMIZED) {                 
+            if (next == NULL)          /* Next ptr. */
+                PerlIO_printf(Perl_debug_log, " (0)");
+            else if (PL_regkind[(U8)op] == BRANCH && PL_regkind[OP(next)] != BRANCH )
+                PerlIO_printf(Perl_debug_log, " (FAIL)");
+            else 
+                PerlIO_printf(Perl_debug_log, " (%"IVdf")", (IV)(next - start));
+            (void)PerlIO_putc(Perl_debug_log, '\n'); 
+        }
+        
       after_print:
        if (PL_regkind[(U8)op] == BRANCHJ) {
            assert(next);
@@ -9025,18 +9149,20 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
        else if ( PL_regkind[(U8)op]  == TRIE ) {
            const regnode *this_trie = node;
            const char op = OP(node);
-            const I32 n = ARG(node);
+            const U32 n = ARG(node);
            const reg_ac_data * const ac = op>=AHOCORASICK ?
-               (reg_ac_data *)r->data->data[n] :
+               (reg_ac_data *)ri->data->data[n] :
                NULL;
-           const reg_trie_data * const trie = op<AHOCORASICK ?
-               (reg_trie_data*)r->data->data[n] :
-               ac->trie;
+           const reg_trie_data * const trie =
+               (reg_trie_data*)ri->data->data[op<AHOCORASICK ? n : ac->trie];
+#ifdef DEBUGGING
+           AV *const trie_words = (AV *) ri->data->data[n + TRIE_WORDS_OFFSET];
+#endif
            const regnode *nextbranch= NULL;
            I32 word_idx;
             sv_setpvn(sv, "", 0);
            for (word_idx= 0; word_idx < (I32)trie->wordcount; word_idx++) {
-               SV ** const elem_ptr = av_fetch(trie->words,word_idx,0);
+               SV ** const elem_ptr = av_fetch(trie_words,word_idx,0);
                
                 PerlIO_printf(Perl_debug_log, "%*s%s ",
                    (int)(2*(indent+3)), "",
@@ -9050,8 +9176,8 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
                 );
                 if (trie->jump) {
                     U16 dist= trie->jump[word_idx+1];
-                   PerlIO_printf(Perl_debug_log, "(%u)\n",
-                        (dist ? this_trie + dist : next) - start);
+                   PerlIO_printf(Perl_debug_log, "(%"UVuf")\n",
+                                 (UV)((dist ? this_trie + dist : next) - start));
                     if (dist) {
                         if (!nextbranch)
                             nextbranch= this_trie + trie->jump[0];    
@@ -9096,12 +9222,10 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
        }
        if (op == CURLYX || op == OPEN)
            indent++;
-       else if (op == WHILEM)
-           indent--;
     }
     CLEAR_OPTSTART;
 #ifdef DEBUG_DUMPUNTIL    
-    PerlIO_printf(Perl_debug_log, "--- %d\n",indent);
+    PerlIO_printf(Perl_debug_log, "--- %d\n", (int)indent);
 #endif
     return node;
 }