This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Stage 1 of threadsafe-ing the trie strucutres - use shared malloc.
[perl5.git] / regcomp.c
index 39a8469..80b8da1 100644 (file)
--- a/regcomp.c
+++ b/regcomp.c
 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. */
@@ -113,13 +114,20 @@ typedef struct RExC_state_t {
     I32                sawback;                /* Did we see \1, ...? */
     U32                seen;
     I32                size;                   /* Code size. */
-    I32                npar;                   /* () count. */
+    I32                npar;                   /* Capture buffer count, (OPEN). */
+    I32                cpar;                   /* Capture buffer count, (CLOSE). */
+    I32                nestroot;               /* root parens we are in - used by accept */
     I32                extralen;
     I32                seen_zerolen;
     I32                seen_evals;
-    regnode    **parens;               /* offsets of each paren */
+    regnode    **open_parens;          /* pointers to open parens */
+    regnode    **close_parens;         /* pointers to close parens */
+    regnode    *opend;                 /* END node in program */
     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
     char       *starttry;              /* -Dr: where regtry was called. */
 #define RExC_starttry  (pRExC_state->starttry)
@@ -135,11 +143,12 @@ typedef struct 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)
@@ -147,12 +156,19 @@ 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)
 #define RExC_seen_evals        (pRExC_state->seen_evals)
 #define RExC_utf8      (pRExC_state->utf8)
 #define RExC_charnames  (pRExC_state->charnames)
-#define RExC_parens    (pRExC_state->parens)
+#define RExC_open_parens       (pRExC_state->open_parens)
+#define RExC_close_parens      (pRExC_state->close_parens)
+#define RExC_opend     (pRExC_state->opend)
+#define RExC_paren_names       (pRExC_state->paren_names)
+#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) == '?' || \
@@ -180,6 +196,14 @@ typedef struct RExC_state_t {
 #endif
 
 
+
+#define PBYTE(u8str,paren) ((U8*)(u8str))[(paren) >> 3]
+#define PBITVAL(paren) (1 << ((paren) & 7))
+#define PAREN_TEST(u8str,paren) ( PBYTE(u8str,paren) & PBITVAL(paren))
+#define PAREN_SET(u8str,paren) PBYTE(u8str,paren) |= PBITVAL(paren)
+#define PAREN_UNSET(u8str,paren) PBYTE(u8str,paren) &= (~PBITVAL(paren))
+
+
 /* About scan_data_t.
 
   During optimisation we recurse through the regexp program performing
@@ -317,11 +341,11 @@ static const scan_data_t zero_scan_data =
 #define SCF_WHILEM_VISITED_POS 0x2000
 
 #define SCF_TRIE_RESTUDY        0x4000 /* Do restudy? */
-
+#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
@@ -348,7 +372,7 @@ 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;                                  \
                                                                        \
@@ -359,10 +383,17 @@ 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
  */
@@ -481,7 +512,7 @@ static const scan_data_t zero_scan_data =
 #define Set_Node_Offset_To_R(node,byte) STMT_START {                   \
     if (! SIZE_ONLY) {                                                 \
        MJD_OFFSET_DEBUG(("** (%d) offset of node %d is %d.\n",         \
-                   __LINE__, (node), (int)(byte)));                    \
+                   __LINE__, (int)(node), (int)(byte)));               \
        if((node) < 0) {                                                \
            Perl_croak(aTHX_ "value of node is %d in Offset macro", (int)(node)); \
        } else {                                                        \
@@ -529,7 +560,7 @@ static const scan_data_t zero_scan_data =
 #define DEBUG_STUDYDATA(data,depth)                                  \
 DEBUG_OPTIMISE_MORE_r(if(data){                                           \
     PerlIO_printf(Perl_debug_log,                                    \
-        "%*s"/* Len:%"IVdf"/%"IVdf" */" Pos:%"IVdf"/%"IVdf           \
+        "%*s"/* Len:%"IVdf"/%"IVdf" */"Pos:%"IVdf"/%"IVdf           \
         " Flags: %"IVdf" Whilem_c: %"IVdf" Lcp: %"IVdf" ",           \
         (int)(depth)*2, "",                                          \
         (IV)((data)->pos_min),                                       \
@@ -666,6 +697,8 @@ STATIC void
 S_cl_and(struct regnode_charclass_class *cl,
        const struct regnode_charclass_class *and_with)
 {
+
+    assert(and_with->type == ANYOF);
     if (!(and_with->flags & ANYOF_CLASS)
        && !(cl->flags & ANYOF_CLASS)
        && (and_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
@@ -818,7 +851,7 @@ S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
         PerlIO_printf( Perl_debug_log, "%.*s", colwidth, "--------");
     PerlIO_printf( Perl_debug_log, "\n");
 
-    for( state = 1 ; state < trie->laststate ; state++ ) {
+    for( state = 1 ; state < trie->statecount ; state++ ) {
        const U32 base = trie->states[ state ].trans.base;
 
         PerlIO_printf( Perl_debug_log, "%*s#%4"UVXf"|", (int)depth * 2 + 2,"", (UV)state);
@@ -901,10 +934,13 @@ S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc
                            (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
                            PERL_PV_ESCAPE_FIRSTCHAR 
                     ) ,
-                TRIE_LIST_ITEM(state,charid).forid,
-                (UV)TRIE_LIST_ITEM(state,charid).newstate
-            );
-        }
+                    TRIE_LIST_ITEM(state,charid).forid,
+                    (UV)TRIE_LIST_ITEM(state,charid).newstate
+                );
+                if (!(charid % 10)) 
+                    PerlIO_printf(Perl_debug_log, "\n%*s| ",
+                        (int)((depth * 2) + 14), "");
+            }
         }
         PerlIO_printf( Perl_debug_log, "\n");
     }
@@ -1096,10 +1132,11 @@ is the recommended Unicode-aware way of saying
     *(d++) = uv;
 */
 
-#define TRIE_STORE_REVCHAR                                                    \
+#define TRIE_STORE_REVCHAR                                                 \
     STMT_START {                                                           \
-       SV *tmp = Perl_newSVpvf_nocontext( "%c", (int)uvc );               \
+       SV *tmp = newSVpvs("");                                            \
        if (UTF) SvUTF8_on(tmp);                                           \
+       Perl_sv_catpvf( aTHX_ tmp, "%c", (int)uvc );                       \
        av_push( TRIE_REVCHARMAP(trie), tmp );                             \
     } STMT_END
 
@@ -1131,9 +1168,8 @@ is the recommended Unicode-aware way of saying
 
 #define TRIE_LIST_PUSH(state,fid,ns) STMT_START {               \
     if ( TRIE_LIST_CUR( state ) >=TRIE_LIST_LEN( state ) ) {    \
-       TRIE_LIST_LEN( state ) *= 2;                            \
-       Renew( trie->states[ state ].trans.list,                \
-              TRIE_LIST_LEN( state ), reg_trie_trans_le );     \
+       U32 ging = TRIE_LIST_LEN( state ) *= 2;                 \
+       Renew( trie->states[ state ].trans.list, ging, reg_trie_trans_le ); \
     }                                                           \
     TRIE_LIST_ITEM( state, TRIE_LIST_CUR( state ) ).forid = fid;     \
     TRIE_LIST_ITEM( state, TRIE_LIST_CUR( state ) ).newstate = ns;   \
@@ -1168,8 +1204,8 @@ is the recommended Unicode-aware way of saying
                                                                 \
     if ( noper_next < tail ) {                                  \
         if (!trie->jump)                                        \
-            Newxz( trie->jump, word_count + 1, U16);            \
-        trie->jump[curword] = (U16)(tail - noper_next);         \
+            trie->jump = PerlMemShared_calloc( word_count + 1, sizeof(U16) ); \
+        trie->jump[curword] = (U16)(noper_next - convert);      \
         if (!jumper)                                            \
             jumper = noper_next;                                \
         if (!nextbranch)                                        \
@@ -1182,7 +1218,8 @@ 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 =                                   \
+               PerlMemShared_calloc( word_count + 1, sizeof(U16));     \
         while ( trie->nextword[dupe] )                          \
             dupe= trie->nextword[dupe];                         \
         trie->nextword[dupe]= curword;                          \
@@ -1220,6 +1257,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     U32 next_alloc = 0;
     regnode *jumper = NULL;
     regnode *nextbranch = NULL;
+    regnode *convert = NULL;
     /* we just use folder as a flag in utf8 */
     const U8 * const folder = ( flags == EXACTF
                        ? PL_fold
@@ -1243,14 +1281,14 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     PERL_UNUSED_ARG(depth);
 #endif
 
-    Newxz( trie, 1, reg_trie_data );
+    trie = 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 = PerlMemShared_calloc( 256, sizeof(U16) );
     if (!(UTF && folder))
-        Newxz( trie->bitmap, ANYOF_BITMAP_SIZE, char );
+       trie->bitmap = PerlMemShared_calloc( ANYOF_BITMAP_SIZE, 1 );
     DEBUG_r({
         trie->words = newAV();
     });
@@ -1268,6 +1306,16 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                   REG_NODE_NUM(last), REG_NODE_NUM(tail),
                   (int)depth);
     });
+   
+   /* Find the node we are going to overwrite */
+    if ( first == startbranch && OP( last ) != BRANCH ) {
+        /* whole branch chain */
+        convert = first;
+    } else {
+        /* branch sub-chain */
+        convert = NEXTOPER( first );
+    }
+        
     /*  -- First loop and Setup --
 
        We first traverse the branches and scan each word to determine if it
@@ -1353,7 +1401,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                (int)TRIE_CHARCOUNT(trie), trie->uniquecharcount,
                (int)trie->minlen, (int)trie->maxlen )
     );
-    Newxz( trie->wordlen, word_count, U32 );
+    trie->wordlen = PerlMemShared_calloc( word_count, sizeof(U32) );
 
     /*
         We now know what we are dealing with in terms of unique chars and
@@ -1392,7 +1440,12 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
 
         STRLEN transcount = 1;
 
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+        DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
+            "%*sCompiling trie using list compiler\n",
+            (int)depth * 2 + 2, ""));
+       
+       trie->states = PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
+                                            sizeof(reg_trie_state) );
         TRIE_LIST_NEW(1);
         next_alloc = 2;
 
@@ -1454,15 +1507,18 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
 
         } /* end second pass */
 
-        trie->laststate = next_alloc;
-        Renew( trie->states, next_alloc, reg_trie_state );
+        /* next alloc is the NEXT state to be allocated */
+        trie->statecount = next_alloc; 
+        trie->states = 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)
-                    );
+        );
 
-        Newxz( trie->trans, transcount ,reg_trie_trans );
+        trie->trans
+           = PerlMemShared_calloc( transcount, sizeof(reg_trie_trans) );
         {
             U32 state;
             U32 tp = 0;
@@ -1493,7 +1549,10 @@ 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
+                           = PerlMemShared_realloc( trie->trans,
+                                                    transcount
+                                                    * sizeof(reg_trie_trans) );
                         Zero( trie->trans + (transcount / 2), transcount / 2 , reg_trie_trans );
                     }
                     base = trie->uniquecharcount + tp - minid;
@@ -1569,11 +1628,15 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
            use TRIE_NODENUM() to convert.
 
         */
-
-
-        Newxz( trie->trans, ( TRIE_CHARCOUNT(trie) + 1 ) * trie->uniquecharcount + 1,
-              reg_trie_trans );
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+        DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
+            "%*sCompiling trie using table compiler\n",
+            (int)depth * 2 + 2, ""));
+
+       trie->trans = PerlMemShared_calloc( ( TRIE_CHARCOUNT(trie) + 1 )
+                                           * trie->uniquecharcount + 1,
+                                           sizeof(reg_trie_trans) );
+        trie->states = PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
+                                            sizeof(reg_trie_state) );
         next_alloc = trie->uniquecharcount + 1;
 
 
@@ -1693,7 +1756,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         const U32 laststate = TRIE_NODENUM( next_alloc );
        U32 state, charid;
         U32 pos = 0, zp=0;
-        trie->laststate = laststate;
+        trie->statecount = laststate;
 
         for ( state = 1 ; state < laststate ; state++ ) {
             U8 flag = 0;
@@ -1730,7 +1793,8 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             }
         }
         trie->lasttrans = pos + 1;
-        Renew( trie->states, laststate + 1, reg_trie_state);
+        trie->states = 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",
@@ -1743,8 +1807,15 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
 
         } /* end table compress */
     }
+    DEBUG_TRIE_COMPILE_MORE_r(
+            PerlIO_printf(Perl_debug_log, "%*sStatecount:%"UVxf" Lasttrans:%"UVxf"\n",
+                (int)depth * 2 + 2, "",
+                (UV)trie->statecount,
+                (UV)trie->lasttrans)
+    );
     /* resize the trans array to remove unused space */
-    Renew( trie->trans, trie->lasttrans, reg_trie_trans);
+    trie->trans = PerlMemShared_realloc( trie->trans, trie->lasttrans
+                                        * sizeof(reg_trie_trans) );
 
     /* and now dump out the compressed format */
     DEBUG_TRIE_COMPILE_r(
@@ -1752,12 +1823,11 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     );
 
     {   /* Modify the program and insert the new TRIE node*/ 
-        regnode *convert;
         U8 nodetype =(U8)(flags & 0xFF);
         char *str=NULL;
         
 #ifdef DEBUGGING
-        regnode *optimize;
+        regnode *optimize = NULL;
         U32 mjd_offset = 0;
         U32 mjd_nodelen = 0;
 #endif
@@ -1770,23 +1840,22 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
            the whole branch sequence, including the first.
          */
         /* Find the node we are going to overwrite */
-        if ( first == startbranch && OP( last ) != BRANCH ) {
-            /* whole branch chain */
-            convert = first;
-            DEBUG_r({
-                const  regnode *nop = NEXTOPER( convert );
-                mjd_offset= Node_Offset((nop));
-                mjd_nodelen= Node_Length((nop));
-            });
-        } else {
+        if ( first != startbranch || OP( last ) == BRANCH ) {
             /* branch sub-chain */
-            convert = NEXTOPER( first );
             NEXT_OFF( first ) = (U16)(last - first);
             DEBUG_r({
                 mjd_offset= Node_Offset((convert));
                 mjd_nodelen= Node_Length((convert));
             });
+            /* whole branch chain */
+        } else {
+            DEBUG_r({
+                const  regnode *nop = NEXTOPER( convert );
+                mjd_offset= Node_Offset((nop));
+                mjd_nodelen= Node_Length((nop));
+            });
         }
+        
         DEBUG_OPTIMISE_r(
             PerlIO_printf(Perl_debug_log, "%*sMJD offset:%"UVuf" MJD length:%"UVuf"\n",
                 (int)depth * 2 + 2, "",
@@ -1798,12 +1867,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         trie->startstate= 1;
         if ( trie->bitmap && !trie->widecharmap && !trie->jump  ) {
             U32 state;
-            DEBUG_OPTIMISE_r(
-                PerlIO_printf(Perl_debug_log, "%*sLaststate:%"UVuf"\n",
-                    (int)depth * 2 + 2, "",
-                    (UV)trie->laststate)
-           );
-            for ( state = 1 ; state < trie->laststate-1 ; state++ ) {
+            for ( state = 1 ; state < trie->statecount-1 ; state++ ) {
                 U32 ofs = 0;
                 I32 idx = -1;
                 U32 count = 0;
@@ -1850,21 +1914,30 @@ 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(
+                    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)
@@ -1881,11 +1954,21 @@ 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;
@@ -1904,7 +1987,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
               jump[0], which is otherwise unused by the jump logic. 
               We use this when dumping a trie and during optimisation. */
            if (trie->jump) 
-               trie->jump[0] = (U16)(tail - nextbranch);
+               trie->jump[0] = (U16)(nextbranch - convert);
             
             /* XXXX */
             if ( !trie->states[trie->startstate].wordnum && trie->bitmap && 
@@ -1912,7 +1995,7 @@ 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;
@@ -1928,9 +2011,9 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                    as we won't use them - (which resources?) dmq */
         }
         /* needed for dumping*/
-        DEBUG_r({
+        DEBUG_r(if (optimize) {
             regnode *opt = convert;
-            while (++opt<optimize) {
+            while ( ++opt < optimize) {
                 Set_Node_Offset_Length(opt,0,0);
             }
             /* 
@@ -1977,10 +2060,10 @@ 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)];
+    reg_trie_data *trie=(reg_trie_data *)RExC_rxi->data->data[ARG(source)];
     U32 *q;
     const U32 ucharcount = trie->uniquecharcount;
-    const U32 numstates = trie->laststate;
+    const U32 numstates = trie->statecount;
     const U32 ubound = trie->lasttrans + ucharcount;
     U32 q_read = 0;
     U32 q_write = 0;
@@ -1996,13 +2079,13 @@ 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 = PerlMemShared_calloc( 1, sizeof(reg_ac_data) );
+    RExC_rxi->data->data[ data_slot ] = (void*)aho;
     aho->trie=trie;
-    aho->states=(reg_trie_state *)savepvn((const char*)trie->states,
-        (trie->laststate+1)*sizeof(reg_trie_state));
+    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 = PerlMemShared_calloc( numstates, sizeof(U32) );
     aho->refcount = 1;
     fail = aho->fail;
     /* initialize fail[0..1] to be 1 so that we always have
@@ -2049,7 +2132,10 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
      */
     fail[ 0 ] = fail[ 1 ] = 0;
     DEBUG_TRIE_COMPILE_r({
-        PerlIO_printf(Perl_debug_log, "%*sStclass Failtable: 0", (int)(depth * 2), "");
+        PerlIO_printf(Perl_debug_log,
+                     "%*sStclass Failtable (%"UVuf" states): 0", 
+                     (int)(depth * 2), "", (UV)numstates
+        );
         for( q_read=1; q_read<numstates; q_read++ ) {
             PerlIO_printf(Perl_debug_log, ", %"UVuf, (UV)fail[q_read]);
         }
@@ -2072,14 +2158,14 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
 #endif
 
 #define DEBUG_PEEP(str,scan,depth) \
-    DEBUG_OPTIMISE_r({ \
+    DEBUG_OPTIMISE_r({if (scan){ \
        SV * const mysv=sv_newmortal(); \
        regnode *Next = regnext(scan); \
        regprop(RExC_rx, mysv, scan); \
-       PerlIO_printf(Perl_debug_log, "%*s" str ">%3d: %s [%d]\n", \
+       PerlIO_printf(Perl_debug_log, "%*s" str ">%3d: %s (%d)\n", \
        (int)depth*2, "", REG_NODE_NUM(scan), SvPV_nolen_const(mysv),\
        Next ? (REG_NODE_NUM(Next)) : 0 ); \
-   });
+   }});
 
 
 
@@ -2237,15 +2323,38 @@ S_join_exact(pTHX_ RExC_state_t *pRExC_state, regnode *scan, I32 *min, U32 flags
 /* Stops at toplevel WHILEM as well as at "last". At end *scanp is set
    to the position after last scanned or to NULL. */
 
-
+#define INIT_AND_WITHP \
+    assert(!and_withp); \
+    Newx(and_withp,1,struct regnode_charclass_class); \
+    SAVEFREEPV(and_withp)
+
+/* this is a chain of data about sub patterns we are processing that
+   need to be handled seperately/specially in study_chunk. Its so
+   we can simulate recursion without losing state.  */
+struct scan_frame;
+typedef struct scan_frame {
+    regnode *last;  /* last node to process in this frame */
+    regnode *next;  /* next node to process when last is reached */
+    struct scan_frame *prev; /*previous frame*/
+    I32 stop; /* what stopparen do we use */
+} scan_frame;
 
 STATIC I32
-S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp, 
+S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                         I32 *minlenp, I32 *deltap,
-                       regnode *last, scan_data_t *data, U32 flags, U32 depth)
+                       regnode *last,
+                       scan_data_t *data,
+                       I32 stopparen,
+                       U8* recursed,
+                       struct regnode_charclass_class *and_withp,
+                       U32 flags, U32 depth)
                        /* scanp: Start here (read-write). */
                        /* deltap: Write maxlen-minlen here. */
                        /* last: Stop before this one. */
+                       /* data: string data about the pattern */
+                       /* stopparen: treat close N as END */
+                       /* recursed: which subroutines have we recursed into */
+                       /* and_withp: Valid if flags & SCF_DO_STCLASS_OR */
 {
     dVAR;
     I32 min = 0, pars = 0, code;
@@ -2255,22 +2364,25 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
     int is_inf_internal = 0;           /* The studied chunk is infinite */
     I32 is_par = OP(scan) == OPEN ? ARG(scan) : 0;
     scan_data_t data_fake;
-    struct regnode_charclass_class and_with; /* Valid if flags & SCF_DO_STCLASS_OR */
     SV *re_trie_maxbuff = NULL;
     regnode *first_non_open = scan;
-
+    I32 stopmin = I32_MAX;
+    scan_frame *frame = NULL;
 
     GET_RE_DEBUG_FLAGS_DECL;
+
 #ifdef DEBUGGING
-    StructCopy(&zero_scan_data, &data_fake, scan_data_t);    
+    StructCopy(&zero_scan_data, &data_fake, scan_data_t);
 #endif
+
     if ( depth == 0 ) {
-        while (first_non_open && OP(first_non_open) == OPEN) 
+        while (first_non_open && OP(first_non_open) == OPEN)
             first_non_open=regnext(first_non_open);
     }
 
 
-    while (scan && OP(scan) != END && scan < last) {
+  fake_study_recurse:
+    while ( scan && OP(scan) != END && scan < last ){
        /* Peephole optimizer: */
        DEBUG_STUDYDATA(data,depth);
        DEBUG_PEEP("Peep",scan,depth);
@@ -2304,12 +2416,12 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
        /* 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 || OP(scan) == SUSPEND) {
+                  || 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 || code == SUSPEND) {
+           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. */
@@ -2317,7 +2429,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                struct regnode_charclass_class accum;
                regnode * const startbranch=scan;
                
-               if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
+               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);
@@ -2328,12 +2440,14 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
 
                    num++;
                    data_fake.flags = 0;
-                   if (data) {         
+                   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)
@@ -2342,13 +2456,14 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                        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, f,depth+1);
+                                         next, &data_fake,
+                                         stopparen, recursed, NULL, f,depth+1);
                    if (min1 > minnext)
                        min1 = minnext;
                    if (max1 < minnext + deltanext)
@@ -2358,6 +2473,13 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    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;
@@ -2365,8 +2487,6 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    }
                    if (flags & SCF_DO_STCLASS)
                        cl_or(pRExC_state, &accum, &this_class);
-                   if (code == SUSPEND)
-                       break;
                }
                if (code == IFTHEN && num < 2) /* Empty ELSE branch */
                    min1 = 0;
@@ -2381,7 +2501,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                if (flags & SCF_DO_STCLASS_OR) {
                    cl_or(pRExC_state, data->start_class, &accum);
                    if (min1) {
-                       cl_and(data->start_class, &and_with);
+                       cl_and(data->start_class, and_withp);
                        flags &= ~SCF_DO_STCLASS;
                    }
                }
@@ -2393,7 +2513,8 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    else {
                        /* Switch to OR mode: cache the old value of
                         * data->start_class */
-                       StructCopy(data->start_class, &and_with,
+                       INIT_AND_WITHP;
+                       StructCopy(data->start_class, and_withp,
                                   struct regnode_charclass_class);
                        flags &= ~SCF_DO_STCLASS_AND;
                        StructCopy(&accum, data->start_class,
@@ -2584,8 +2705,14 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                             if ( ((made == MADE_EXACT_TRIE && 
                                  startbranch == first) 
                                  || ( first_non_open == first )) && 
-                                 depth==0 ) 
+                                 depth==0 ) {
                                 flags |= SCF_TRIE_RESTUDY;
+                                if ( startbranch == first 
+                                     && scan == tail ) 
+                                {
+                                    RExC_seen &=~REG_TOP_LEVEL_BRANCHES;
+                                }
+                            }
 #endif
                         }
                     }
@@ -2598,6 +2725,63 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
            } 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);
@@ -2659,7 +2843,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                else
                    data->start_class->flags |= ANYOF_UNICODE_ALL;
                data->start_class->flags &= ~ANYOF_EOS;
-               cl_and(data->start_class, &and_with);
+               cl_and(data->start_class, and_withp);
            }
            flags &= ~SCF_DO_STCLASS;
        }
@@ -2707,13 +2891,10 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                        ANYOF_BITMAP_SET(data->start_class, uc);
                    data->start_class->flags &= ~ANYOF_EOS;
                }
-               cl_and(data->start_class, &and_with);
+               cl_and(data->start_class, and_withp);
            }
            flags &= ~SCF_DO_STCLASS;
        }
-       else if (OP(scan)==RECURSE) {
-            ARG2L_SET( scan, RExC_parens[ARG(scan)-1] - scan ); 
-       } 
        else if (strchr((const char*)PL_varies,OP(scan))) {
            I32 mincount, maxcount, minnext, deltanext, fl = 0;
            I32 f = flags, pos_before = 0;
@@ -2757,8 +2938,15 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                }
                goto optimize_curly_tail;
            case CURLY:
-               mincount = ARG1(scan);
-               maxcount = ARG2(scan);
+               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);
@@ -2794,7 +2982,8 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    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,
+               minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext, 
+                                     last, data, stopparen, recursed, NULL,
                                      (mincount == 0
                                        ? (f & ~SCF_DO_SUBSTR) : f),depth+1);
 
@@ -2807,7 +2996,8 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    else if (flags & SCF_DO_STCLASS_AND) {
                        /* Switch to OR mode: cache the old value of
                         * data->start_class */
-                       StructCopy(data->start_class, &and_with,
+                       INIT_AND_WITHP;
+                       StructCopy(data->start_class, and_withp,
                                   struct regnode_charclass_class);
                        flags &= ~SCF_DO_STCLASS_AND;
                        StructCopy(&this_class, data->start_class,
@@ -2818,7 +3008,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                } 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_with);
+                       cl_and(data->start_class, and_withp);
                    }
                    else if (flags & SCF_DO_STCLASS_AND)
                        cl_and(data->start_class, &this_class);
@@ -2868,10 +3058,15 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    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. */
@@ -2908,8 +3103,13 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                        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. */
@@ -2933,7 +3133,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
 #endif
                        /* Optimize again: */
                        study_chunk(pRExC_state, &nxt1, minlenp, &deltanext, nxt,
-                                   NULL, 0,depth+1);
+                                   NULL, stopparen, recursed, NULL, 0,depth+1);
                    }
                    else
                        oscan->flags = 0;
@@ -3265,7 +3465,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    break;
                }
                if (flags & SCF_DO_STCLASS_OR)
-                   cl_and(data->start_class, &and_with);
+                   cl_and(data->start_class, and_withp);
                flags &= ~SCF_DO_STCLASS;
            }
        }
@@ -3297,6 +3497,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                }
                 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);
@@ -3307,13 +3508,14 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     f |= SCF_WHILEM_VISITED_POS;
                 next = regnext(scan);
                 nscan = NEXTOPER(NEXTOPER(scan));
-                minnext = study_chunk(pRExC_state, &nscan, minlenp, &deltanext, last, &data_fake, f,depth+1);
+                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");
+                       FAIL("Variable length lookbehind not implemented");
                     }
                     else if (minnext > (I32)U8_MAX) {
-                        vFAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
+                       FAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
                     }
                     scan->flags = (U8)minnext;
                 }
@@ -3367,6 +3569,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                 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
@@ -3379,28 +3582,28 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     f |= SCF_WHILEM_VISITED_POS;
                 next = regnext(scan);
                 nscan = NEXTOPER(NEXTOPER(scan));
-                
-                *minnextp = study_chunk(pRExC_state, &nscan, minnextp, &deltanext, last, &data_fake, f,depth+1);
+
+                *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");
+                       FAIL("Variable length lookbehind not implemented");
                     }
                     else if (*minnextp > (I32)U8_MAX) {
-                        vFAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)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++;
@@ -3434,9 +3637,13 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
 #endif
        }
        else if (OP(scan) == OPEN) {
-           pars++;
+           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);
 
@@ -3450,7 +3657,19 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                if (data)
                    data->flags |= SF_HAS_EVAL;
        }
-       else if (OP(scan) == LOGICAL && scan->flags == 2) { /* Embedded follows */
+       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;
+           }
+       }
+       else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */
+       {
                if (flags & SCF_DO_SUBSTR) {
                    scan_commit(pRExC_state,data,minlenp);
                    data->longest = &(data->longest_float);
@@ -3460,14 +3679,28 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    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        
+#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 
+               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) ];
+            reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
             I32 max1 = 0, min1 = I32_MAX;
             struct regnode_charclass_class accum;
 
@@ -3495,7 +3728,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     }
                     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;
@@ -3506,14 +3739,15 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
     
                     if (trie->jump[word]) {
                         if (!nextbranch)
-                            nextbranch = tail - trie->jump[0];
-                        scan= tail - trie->jump[word];
+                            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, f,depth+1);
+                        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);
@@ -3527,7 +3761,13 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     
                     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;
@@ -3548,7 +3788,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
             if (flags & SCF_DO_STCLASS_OR) {
                 cl_or(pRExC_state, data->start_class, &accum);
                 if (min1) {
-                    cl_and(data->start_class, &and_with);
+                    cl_and(data->start_class, and_withp);
                     flags &= ~SCF_DO_STCLASS;
                 }
             }
@@ -3560,7 +3800,8 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                 else {
                     /* Switch to OR mode: cache the old value of
                      * data->start_class */
-                    StructCopy(data->start_class, &and_with,
+                   INIT_AND_WITHP;
+                    StructCopy(data->start_class, and_withp,
                                struct regnode_charclass_class);
                     flags &= ~SCF_DO_STCLASS_AND;
                     StructCopy(&accum, data->start_class,
@@ -3574,7 +3815,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
         }
 #else
        else if (PL_regkind[OP(scan)] == TRIE) {
-           reg_trie_data *trie = (reg_trie_data*)RExC_rx->data->data[ ARG(scan) ];
+           reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
            U8*bang=NULL;
            
            min += trie->minlen;
@@ -3595,8 +3836,17 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
        /* 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);
+
     *scanp = scan;
     *deltap = is_inf_internal ? I32_MAX : delta;
     if (flags & SCF_DO_SUBSTR && is_inf)
@@ -3612,33 +3862,30 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
        data->flags &= ~SF_IN_PAR;
     }
     if (flags & SCF_DO_STCLASS_OR)
-       cl_and(data->start_class, &and_with);
+       cl_and(data->start_class, and_withp);
     if (flags & SCF_TRIE_RESTUDY)
         data->flags |=         SCF_TRIE_RESTUDY;
     
     DEBUG_STUDYDATA(data,depth);
     
-    return min;
+    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) {
-       Renewc(RExC_rx->data,
-              sizeof(*RExC_rx->data) + sizeof(void*) * (RExC_rx->data->count + n - 1),
-              char, struct reg_data);
-       Renew(RExC_rx->data->what, RExC_rx->data->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;
 }
 
 #ifndef PERL_IN_XSUB_RE
@@ -3695,14 +3942,17 @@ Perl_reginitcolors(pTHX)
  * Beware that the optimization-preparation code in here knows about some
  * of the structure of the compiled regexp.  [I'll say.]
  */
+
+
+
 #ifndef PERL_IN_XSUB_RE
-#define CORE_ONLY_BLOCK(c) {c}{
 #define RE_ENGINE_PTR &PL_core_reg_engine
 #else
-#define CORE_ONLY_BLOCK(c) {
 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 }
  
 regexp *
@@ -3711,13 +3961,14 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     dVAR;
     GET_RE_DEBUG_FLAGS_DECL;
     DEBUG_r(if (!PL_colorset) reginitcolors());
-    CORE_ONLY_BLOCK(
+#ifndef PERL_IN_XSUB_RE
+    BEGIN_BLOCK
     /* 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);
-        if (ptr && SvIOK(*ptr)) {
+        if (ptr && SvIOK(*ptr) && SvIV(*ptr)) {
             const regexp_engine *eng=INT2PTR(regexp_engine*,SvIV(*ptr));
             DEBUG_COMPILE_r({
                 PerlIO_printf(Perl_debug_log, "Using engine %"UVxf"\n",
@@ -3725,8 +3976,12 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
             });            
             return CALLREGCOMP_ENG(eng, exp, xend, pm);
         } 
-    })
+    }
+    END_BLOCK
+#endif
+    BEGIN_BLOCK    
     register regexp *r;
+    register regexp_internal *ri;
     regnode *scan;
     regnode *first;
     I32 flags;
@@ -3767,12 +4022,19 @@ 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;
     RExC_whilem_seen = 0;
     RExC_charnames = NULL;
-    RExC_parens= NULL;
-    
+    RExC_open_parens = NULL;
+    RExC_close_parens = NULL;
+    RExC_opend = NULL;
+    RExC_paren_names = NULL;
+    RExC_recurse = NULL;
+    RExC_recurse_count = 0;
+
 #if 0 /* REGC() is (currently) a NOP at the first pass.
        * Clever compilers notice this and complain. --jhi */
     REGC((U8)REG_MAGIC, (char*)RExC_emit);
@@ -3782,15 +4044,14 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
        RExC_precomp = NULL;
        return(NULL);
     }
-    DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "Required "));
-    DEBUG_COMPILE_r(PerlIO_printf(Perl_debug_log, "size %"IVdf" nodes ", (IV)RExC_size));
-    DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "\nStarting second pass (creation)\n"));
     DEBUG_PARSE_r({
+        PerlIO_printf(Perl_debug_log, 
+            "Required size %"IVdf" nodes\n"
+            "Starting second pass (creation)\n", 
+            (IV)RExC_size);
         RExC_lastnum=0; 
         RExC_lastparse=NULL; 
     });
-
-    
     /* Small enough for pointer-storage convention?
        If extralen==0, this means that we will not need long jumps. */
     if (RExC_size >= 0x10000L && RExC_extralen)
@@ -3800,50 +4061,56 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     if (RExC_whilem_seen > 15)
        RExC_whilem_seen = 15;
 
+#ifdef DEBUGGING
+    /* Make room for a sentinel value at the end of the program */
+    RExC_size++;
+#endif
+
     /* 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;                       
+    
     if (RExC_seen & REG_SEEN_RECURSE) {
-        Newx(RExC_parens, RExC_npar,regnode *);
-        SAVEFREEPV(RExC_parens);
+        Newxz(RExC_open_parens, RExC_npar,regnode *);
+        SAVEFREEPV(RExC_open_parens);
+        Newxz(RExC_close_parens,RExC_npar,regnode *);
+        SAVEFREEPV(RExC_close_parens);
     }
 
     /* 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 */
@@ -3851,51 +4118,69 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_end = xend;
     RExC_naughty = 0;
     RExC_npar = 1;
-    RExC_emit_start = r->program;
-    RExC_emit = r->program;
+    RExC_cpar = 1;
+    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 */
+    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;
     REGC((U8)REG_MAGIC, (char*) RExC_emit++);
-    r->data = 0;
     if (reg(pRExC_state, 0, &flags,1) == NULL)
        return(NULL);
 
     /* XXXX To minimize changes to RE engine we always allocate
        3-units-long substrs field. */
     Newx(r->substrs, 1, struct reg_substr_data);
+    if (RExC_recurse_count) {
+        Newxz(RExC_recurse,RExC_recurse_count,regnode *);
+        SAVEFREEPV(RExC_recurse);
+    }
 
 reStudy:
     r->minlen = minlen = sawplus = sawopen = 0;
     Zero(r->substrs, 1, struct reg_substr_data);
-    StructCopy(&zero_scan_data, &data, scan_data_t);
 
 #ifdef TRIE_STUDY_OPT
     if ( restudied ) {
+        U32 seen=RExC_seen;
         DEBUG_OPTIMISE_r(PerlIO_printf(Perl_debug_log,"Restudying\n"));
-        RExC_state=copyRExC_state;
+        
+        RExC_state = copyRExC_state;
+        if (seen & REG_TOP_LEVEL_BRANCHES) 
+            RExC_seen |= REG_TOP_LEVEL_BRANCHES;
+        else
+            RExC_seen &= ~REG_TOP_LEVEL_BRANCHES;
         if (data.last_found) {
             SvREFCNT_dec(data.longest_fixed);
            SvREFCNT_dec(data.longest_float);
            SvREFCNT_dec(data.last_found);
        }
+       StructCopy(&zero_scan_data, &data, scan_data_t);
     } else {
-        copyRExC_state=RExC_state;
+        StructCopy(&zero_scan_data, &data, scan_data_t);
+        copyRExC_state = RExC_state;
     }
+#else
+    StructCopy(&zero_scan_data, &data, scan_data_t);
 #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 */
-    if (OP(scan) != BRANCH) {  /* Only one top-level choice. */
+    if (!(RExC_seen & REG_TOP_LEVEL_BRANCHES)) { /*  Only one top-level choice. */
        I32 fake;
        STRLEN longest_float_length, longest_fixed_length;
        struct regnode_charclass_class ch_class; /* pointed to by data */
@@ -3934,76 +4219,78 @@ 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 =
+                   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 =
+                   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 && (OP(first) == STAR &&
+       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
-       DEBUG_COMPILE_r(
+       DEBUG_PARSE_r(
            if (!restudied)
                PerlIO_printf(Perl_debug_log, "first at %"IVdf"\n",
                              (IV)(first - scan + 1))
         );
 #else
-       DEBUG_COMPILE_r(
+       DEBUG_PARSE_r(
            PerlIO_printf(Perl_debug_log, "first at %"IVdf"\n",
                (IV)(first - scan + 1))
         );
@@ -4021,23 +4308,23 @@ reStudy:
        * it happens that c_offset_min has been invalidated, since the
        * earlier string may buy us something the later one won't.]
        */
-       minlen = 0;
-
+       
        data.longest_fixed = newSVpvs("");
        data.longest_float = newSVpvs("");
        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;
        } else                          /* XXXX Check for BOUND? */
            stclass_flag = 0;
        data.last_closep = &last_close;
-
+        
        minlen = study_chunk(pRExC_state, &first, &minlen, &fake, scan + RExC_size, /* Up to end */
-                            &data, SCF_DO_SUBSTR | SCF_WHILEM_VISITED_POS | stclass_flag,0);
+            &data, -1, NULL, NULL,
+            SCF_DO_SUBSTR | SCF_WHILEM_VISITED_POS | stclass_flag,0);
 
        
         CHECK_RESTUDY_GOTO;
@@ -4046,8 +4333,8 @@ 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;
+            && (!(RExC_seen & REG_SEEN_GPOS) || (r->extflags & RXf_ANCH_GPOS)))
+           r->extflags |= RXf_CHECK_ALL;
        scan_commit(pRExC_state, &data,&minlen);
        SvREFCNT_dec(data.last_found);
 
@@ -4059,7 +4346,7 @@ 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;
 
@@ -4093,7 +4380,7 @@ 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 {
@@ -4111,7 +4398,7 @@ 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;
 
@@ -4137,7 +4424,7 @@ 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 {
@@ -4145,23 +4432,23 @@ 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,
@@ -4175,8 +4462,8 @@ 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;
@@ -4187,10 +4474,10 @@ 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 )
@@ -4205,16 +4492,17 @@ reStudy:
        struct regnode_charclass_class ch_class;
        I32 last_close = 0;
        
-       DEBUG_COMPILE_r(PerlIO_printf(Perl_debug_log, "\n"));
+       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;
 
+        
        minlen = study_chunk(pRExC_state, &scan, &minlen, &fake, scan + RExC_size,
-           &data, SCF_DO_STCLASS_AND|SCF_WHILEM_VISITED_POS,0);
-
+           &data, -1, NULL, NULL, SCF_DO_STCLASS_AND|SCF_WHILEM_VISITED_POS,0);
+        
         CHECK_RESTUDY_GOTO;
 
        r->check_substr = r->check_utf8 = r->anchored_substr = r->anchored_utf8
@@ -4222,15 +4510,15 @@ 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,
@@ -4241,34 +4529,54 @@ reStudy:
 
     /* Guard against an embedded (?=) or (?<=) with a longer minlen than
        the "real" pattern. */
+    DEBUG_OPTIMISE_r({
+       PerlIO_printf(Perl_debug_log,"minlen: %"IVdf" r->minlen:%"IVdf"\n",
+                     (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->intflags |= PREGf_VERBARG_SEEN;
+    if (RExC_seen & REG_SEEN_CUTGROUP)
+       r->intflags |= PREGf_CUTGROUP_SEEN;
+    if (RExC_paren_names)
+        r->paren_names = (HV*)SvREFCNT_inc(RExC_paren_names);
+    else
+        r->paren_names = NULL;
+               
+    if (RExC_recurse_count) {
+        for ( ; RExC_recurse_count ; RExC_recurse_count-- ) {
+            const regnode *scan = RExC_recurse[RExC_recurse_count-1];
+            ARG2L_SET( scan, RExC_open_parens[ARG(scan)-1] - scan );
+        }
+    }
     Newxz(r->startp, RExC_npar, I32);
     Newxz(r->endp, RExC_npar, I32);
-    
-    DEBUG_r( RX_DEBUG_on(r) );
+    /* assume we don't need to swap parens around before we match */
+
     DEBUG_DUMP_r({
         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");
     });
@@ -4280,6 +4588,96 @@ reStudy:
 #undef END_BLOCK
 #undef RE_ENGINE_PTR
 
+#ifndef PERL_IN_XSUB_RE
+SV*
+Perl_reg_named_buff_sv(pTHX_ SV* namesv)
+{
+    I32 parno = 0; /* no match */
+    if (PL_curpm) {
+        const REGEXP * const rx = PM_GETRE(PL_curpm);
+        if (rx && rx->paren_names) {            
+            HE *he_str = hv_fetch_ent( rx->paren_names, namesv, 0, 0 );
+            if (he_str) {
+                IV i;
+                SV* sv_dat=HeVAL(he_str);
+                I32 *nums=(I32*)SvPVX(sv_dat);
+                for ( i=0; i<SvIVX(sv_dat); i++ ) {
+                    if ((I32)(rx->lastparen) >= nums[i] &&
+                        rx->endp[nums[i]] != -1) 
+                    {
+                        parno = nums[i];
+                        break;
+                    }
+                }
+            }
+        }
+    }
+    if ( !parno ) {
+        return 0;
+    } 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);
+    }
+}
+#endif
+
+/* Scans the name of a named buffer from the pattern.
+ * If flags is REG_RSN_RETURN_NULL returns null.
+ * If flags is REG_RSN_RETURN_NAME returns an SV* containing the name
+ * If flags is REG_RSN_RETURN_DATA returns the data SV* corresponding
+ * to the parsed name as looked up in the RExC_paren_names hash.
+ * If there is an error throws a vFAIL().. type exception.
+ */
+
+#define REG_RSN_RETURN_NULL    0
+#define REG_RSN_RETURN_NAME    1
+#define REG_RSN_RETURN_DATA    2
+
+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 ( flags ) {
+        SV* sv_name = sv_2mortal(Perl_newSVpvn(aTHX_ name_start,
+            (int)(RExC_parse - name_start)));
+       if (UTF)
+            SvUTF8_on(sv_name);
+        if ( flags == REG_RSN_RETURN_NAME)
+            return sv_name;
+        else if (flags==REG_RSN_RETURN_DATA) {
+            HE *he_str = NULL;
+            SV *sv_dat = NULL;
+            if ( ! sv_name )      /* should not happen*/
+                Perl_croak(aTHX_ "panic: no svname in reg_scan_name");
+            if (RExC_paren_names)
+                he_str = hv_fetch_ent( RExC_paren_names, sv_name, 0, 0 );
+            if ( he_str )
+                sv_dat = HeVAL(he_str);
+            if ( ! sv_dat )
+                vFAIL("Reference to nonexistent named group");
+            return sv_dat;
+        }
+        else {
+            Perl_croak(aTHX_ "panic: bad flag in reg_scan_name");
+        }
+        /* NOT REACHED */
+    }
+    return NULL;
+}
+
 #define DEBUG_PARSE_MSG(funcname)     DEBUG_PARSE_r({           \
     int rem=(int)(RExC_end - RExC_parse);                       \
     int cut;                                                    \
@@ -4304,9 +4702,9 @@ reStudy:
     else                                                        \
        num=REG_NODE_NUM(RExC_emit);                             \
     if (RExC_lastnum!=num)                                      \
-       PerlIO_printf(Perl_debug_log,"|%4d",num);                 \
+       PerlIO_printf(Perl_debug_log,"|%4d",num);                \
     else                                                        \
-       PerlIO_printf(Perl_debug_log,"|%4s","");                  \
+       PerlIO_printf(Perl_debug_log,"|%4s","");                 \
     PerlIO_printf(Perl_debug_log,"|%*s%-4s",                    \
         (int)((depth*2)), "",                                   \
         (funcname)                                              \
@@ -4341,6 +4739,10 @@ reStudy:
 #define REGTAIL_STUDY(x,y,z) regtail((x),(y),(z),depth+1)
 #endif
 
+/* this idea is borrowed from STR_WITH_LEN in handy.h */
+#define CHECK_WORD(s,v,l)  \
+    (((sizeof(s)-1)==(l)) && (strnEQ(start_verb, (s ""), (sizeof(s)-1))))
+
 STATIC regnode *
 S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
     /* paren: Parenthesized? 0=top, 1=(, inside: changed to letter. */
@@ -4377,6 +4779,111 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
 
     /* Make an OPEN node, if parenthesized. */
     if (paren) {
+        if ( *RExC_parse == '*') { /* (*VERB:ARG) */
+           char *start_verb = RExC_parse;
+           STRLEN verb_len = 0;
+           char *start_arg = NULL;
+           unsigned char op = 0;
+           int argok = 1;
+           int internal_argval = 0; /* internal_argval is only useful if !argok */
+           while ( *RExC_parse && *RExC_parse != ')' ) {
+               if ( *RExC_parse == ':' ) {
+                   start_arg = RExC_parse + 1;
+                   break;
+               }
+               RExC_parse++;
+           }
+           ++start_verb;
+           verb_len = RExC_parse - start_verb;
+           if ( start_arg ) {
+               RExC_parse++;
+               while ( *RExC_parse && *RExC_parse != ')' ) 
+                   RExC_parse++;
+               if ( *RExC_parse != ')' ) 
+                   vFAIL("Unterminated verb pattern argument");
+               if ( RExC_parse == start_arg )
+                   start_arg = NULL;
+           } else {
+               if ( *RExC_parse != ')' )
+                   vFAIL("Unterminated verb pattern");
+           }
+           
+           switch ( *start_verb ) {
+            case 'A':  /* (*ACCEPT) */
+                if ( CHECK_WORD("ACCEPT",start_verb,verb_len) ) {
+                   op = ACCEPT;
+                   internal_argval = RExC_nestroot;
+               }
+               break;
+            case 'C':  /* (*COMMIT) */
+                if ( CHECK_WORD("COMMIT",start_verb,verb_len) )
+                    op = COMMIT;
+                break;
+            case 'F':  /* (*FAIL) */
+                if ( verb_len==1 || CHECK_WORD("FAIL",start_verb,verb_len) ) {
+                   op = OPFAIL;
+                   argok = 0;
+               }
+               break;
+            case ':':  /* (*:NAME) */
+           case 'M':  /* (*MARK:NAME) */
+               if ( verb_len==0 || CHECK_WORD("MARK",start_verb,verb_len) ) {
+                    op = MARKPOINT;
+                    argok = -1;
+                }
+                break;
+            case 'P':  /* (*PRUNE) */
+                if ( CHECK_WORD("PRUNE",start_verb,verb_len) )
+                    op = PRUNE;
+                break;
+            case 'S':   /* (*SKIP) */  
+                if ( CHECK_WORD("SKIP",start_verb,verb_len) ) 
+                    op = SKIP;
+                break;
+            case 'T':  /* (*THEN) */
+                /* [19:06] <TimToady> :: is then */
+                if ( CHECK_WORD("THEN",start_verb,verb_len) ) {
+                    op = CUTGROUP;
+                    RExC_seen |= REG_SEEN_CUTGROUP;
+                }
+                break;
+           }
+           if ( ! op ) {
+               RExC_parse++;
+               vFAIL3("Unknown verb pattern '%.*s'",
+                   verb_len, start_verb);
+           }
+           if ( argok ) {
+                if ( start_arg && internal_argval ) {
+                   vFAIL3("Verb pattern '%.*s' may not have an argument",
+                       verb_len, start_verb); 
+               } else if ( argok < 0 && !start_arg ) {
+                    vFAIL3("Verb pattern '%.*s' has a mandatory argument",
+                       verb_len, start_verb);    
+               } else {
+                   ret = reganode(pRExC_state, op, internal_argval);
+                   if ( ! internal_argval && ! SIZE_ONLY ) {
+                        if (start_arg) {
+                            SV *sv = newSVpvn( start_arg, RExC_parse - start_arg);
+                            ARG(ret) = add_data( pRExC_state, 1, "S" );
+                            RExC_rxi->data->data[ARG(ret)]=(void*)sv;
+                            ret->flags = 0;
+                        } else {
+                            ret->flags = 1; 
+                        }
+                    }              
+               }
+               if (!internal_argval)
+                   RExC_seen |= REG_SEEN_VERBARG;
+           } else if ( start_arg ) {
+               vFAIL3("Verb pattern '%.*s' may not have an argument",
+                       verb_len, start_verb);    
+           } else {
+               ret = reg_node(pRExC_state, op);
+           }
+           nextchar(pRExC_state);
+           return ret;
+        } else 
        if (*RExC_parse == '?') { /* (?...) */
            U32 posflags = 0, negflags = 0;
            U32 *flagsp = &posflags;
@@ -4387,16 +4894,72 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            paren = *RExC_parse++;
            ret = NULL;                 /* For look-ahead/behind. */
            switch (paren) {
+
            case '<':           /* (?<...) */
-               RExC_seen |= REG_SEEN_LOOKBEHIND;
                if (*RExC_parse == '!')
                    paren = ',';
-               if (*RExC_parse != '=' && *RExC_parse != '!')
-                   goto unknown;
+               else if (*RExC_parse != '=') 
+               {               /* (?<...>) */
+                   char *name_start;
+                   SV *svname;
+                   paren= '>';
+            case '\'':          /* (?'...') */
+                   name_start= RExC_parse;
+                   svname = reg_scan_name(pRExC_state,
+                       SIZE_ONLY ?  /* reverse test from the others */
+                       REG_RSN_RETURN_NAME : 
+                       REG_RSN_RETURN_NULL);
+                   if (RExC_parse == name_start)
+                       goto unknown;
+                   if (*RExC_parse != paren)
+                       vFAIL2("Sequence (?%c... not terminated",
+                           paren=='>' ? '<' : paren);
+                   if (SIZE_ONLY) {
+                       HE *he_str;
+                       SV *sv_dat = NULL;
+                        if (!svname) /* shouldnt happen */
+                            Perl_croak(aTHX_
+                                "panic: reg_scan_name returned NULL");
+                        if (!RExC_paren_names) {
+                            RExC_paren_names= newHV();
+                            sv_2mortal((SV*)RExC_paren_names);
+                        }
+                        he_str = hv_fetch_ent( RExC_paren_names, svname, 1, 0 );
+                        if ( he_str )
+                            sv_dat = HeVAL(he_str);
+                        if ( ! sv_dat ) {
+                            /* croak baby croak */
+                            Perl_croak(aTHX_
+                                "panic: paren_name hash element allocation failed");
+                        } else if ( SvPOK(sv_dat) ) {
+                            IV count=SvIV(sv_dat);
+                            I32 *pv=(I32*)SvGROW(sv_dat,SvCUR(sv_dat)+sizeof(I32)+1);
+                            SvCUR_set(sv_dat,SvCUR(sv_dat)+sizeof(I32));
+                            pv[count]=RExC_npar;
+                            SvIVX(sv_dat)++;
+                        } else {
+                            (void)SvUPGRADE(sv_dat,SVt_PVNV);
+                            sv_setpvn(sv_dat, (char *)&(RExC_npar), sizeof(I32));
+                            SvIOK_on(sv_dat);
+                            SvIVX(sv_dat)= 1;
+                        }
+
+                        /*sv_dump(sv_dat);*/
+                    }
+                    nextchar(pRExC_state);
+                   paren = 1;
+                   goto capturing_parens;
+               }
+                RExC_seen |= REG_SEEN_LOOKBEHIND;
                RExC_parse++;
            case '=':           /* (?=...) */
            case '!':           /* (?!...) */
                RExC_seen_zerolen++;
+               if (*RExC_parse == ')') {
+                   ret=reg_node(pRExC_state, OPFAIL);
+                   nextchar(pRExC_state);
+                   return ret;
+               }
            case ':':           /* (?:...) */
            case '>':           /* (?>...) */
                break;
@@ -4412,41 +4975,96 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                nextchar(pRExC_state);
                *flagp = TRYAGAIN;
                return NULL;
-            case 'R' :
-                if (*RExC_parse != ')')
+           case '0' :           /* (?0) */
+           case 'R' :           /* (?R) */
+               if (*RExC_parse != ')')
                    FAIL("Sequence (?R) not terminated");
-               reg_node(pRExC_state, SRECURSE);
-               break;
+               ret = reg_node(pRExC_state, GOSTART);
+               nextchar(pRExC_state);
+               return ret;
+               /*notreached*/
+            { /* named and numeric backreferences */
+                I32 num;
+                char * parse_start;
+            case '&':            /* (?&NAME) */
+                parse_start = RExC_parse - 1;
+                {
+                   SV *sv_dat = reg_scan_name(pRExC_state,
+                       SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
+                    num = sv_dat ? *((I32 *)SvPVX(sv_dat)) : 0;
+                }
+                goto gen_recurse_regop;
+                /* NOT REACHED */
+            case '+':
+                if (!(RExC_parse[0] >= '1' && RExC_parse[0] <= '9')) {
+                    RExC_parse++;
+                    vFAIL("Illegal pattern");
+                }
+                goto parse_recursion;
+                /* NOT REACHED*/
+            case '-': /* (?-1) */
+                if (!(RExC_parse[0] >= '1' && RExC_parse[0] <= '9')) {
+                    RExC_parse--; /* rewind to let it be handled later */
+                    goto parse_flags;
+                } 
+                /*FALLTHROUGH */
             case '1': case '2': case '3': case '4': /* (?1) */
            case '5': case '6': case '7': case '8': case '9':
                RExC_parse--;
-           {
-               const I32 num = atoi(RExC_parse);
-               char * const parse_start = RExC_parse - 1; /* MJD */
+              parse_recursion:
+               num = atoi(RExC_parse);
+               parse_start = RExC_parse - 1; /* MJD */
+               if (*RExC_parse == '-')
+                   RExC_parse++;
                while (isDIGIT(*RExC_parse))
                        RExC_parse++;
                if (*RExC_parse!=')') 
                    vFAIL("Expecting close bracket");
-                ret = reganode(pRExC_state, RECURSE, num);
+                       
+              gen_recurse_regop:
+                if ( paren == '-' ) {
+                    /*
+                    Diagram of capture buffer numbering.
+                    Top line is the normal capture buffer numbers
+                    Botton line is the negative indexing as from
+                    the X (the (?-2))
+
+                    +   1 2    3 4 5 X          6 7
+                       /(a(x)y)(a(b(c(?-2)d)e)f)(g(h))/
+                    -   5 4    3 2 1 X          x x
+
+                    */
+                    num = RExC_npar + num;
+                    if (num < 1)  {
+                        RExC_parse++;
+                        vFAIL("Reference to nonexistent group");
+                    }
+                } else if ( paren == '+' ) {
+                    num = RExC_npar + num - 1;
+                }
+
+                ret = reganode(pRExC_state, GOSUB, num);
                 if (!SIZE_ONLY) {
                    if (num > (I32)RExC_rx->nparens) {
                        RExC_parse++;
                        vFAIL("Reference to nonexistent group");
                    }
-                   ARG2L_SET( ret, 0);
+                   ARG2L_SET( ret, RExC_recurse_count++);
                     RExC_emit++;
                    DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
-                       "Recurse #%"UVuf" to %"IVdf"\n", ARG(ret), ARG2L(ret)));
-               } else{
+                       "Recurse #%"UVuf" to %"IVdf"\n", (UV)ARG(ret), (IV)ARG2L(ret)));
+               } else {
                    RExC_size++;
-                   RExC_seen|=REG_SEEN_RECURSE;
                }
+               RExC_seen |= REG_SEEN_RECURSE;
                 Set_Node_Length(ret, 1 + regarglen[OP(ret)]); /* MJD */
                Set_Node_Offset(ret, parse_start); /* MJD */
 
                 nextchar(pRExC_state);
                 return ret;
-            }
+            } /* named and numeric backreferences */
+            /* NOT REACHED */
+
            case 'p':           /* (?p...) */
                if (SIZE_ONLY && ckWARN2(WARN_DEPRECATED, WARN_REGEXP))
                    vWARNdep(RExC_parse, "(?p{}) is deprecated - use (??{})");
@@ -4459,7 +5077,8 @@ 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;
 
@@ -4494,9 +5113,9 @@ 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 */
@@ -4529,6 +5148,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            }
            case '(':           /* (?(?{...})...) and (?(?=...)...) */
            {
+               int is_define= 0;
                if (RExC_parse[0] == '?') {        /* (?(?...)) */
                    if (RExC_parse[1] == '=' || RExC_parse[1] == '!'
                        || RExC_parse[1] == '<'
@@ -4542,6 +5162,55 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                        goto insert_if;
                    }
                }
+               else if ( RExC_parse[0] == '<'     /* (?(<NAME>)...) */
+                        || RExC_parse[0] == '\'' ) /* (?('NAME')...) */
+               {
+                   char ch = RExC_parse[0] == '<' ? '>' : '\'';
+                   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 != ch)
+                        vFAIL2("Sequence (?(%c... not terminated",
+                            (ch == '>' ? '<' : ch));
+                    RExC_parse++;
+                   if (!SIZE_ONLY) {
+                        num = add_data( pRExC_state, 1, "S" );
+                        RExC_rxi->data->data[num]=(void*)sv_dat;
+                        SvREFCNT_inc(sv_dat);
+                    }
+                    ret = reganode(pRExC_state,NGROUPP,num);
+                    goto insert_if_check_paren;
+               }
+               else if (RExC_parse[0] == 'D' &&
+                        RExC_parse[1] == 'E' &&
+                        RExC_parse[2] == 'F' &&
+                        RExC_parse[3] == 'I' &&
+                        RExC_parse[4] == 'N' &&
+                        RExC_parse[5] == 'E')
+               {
+                   ret = reganode(pRExC_state,DEFINEP,0);
+                   RExC_parse +=6 ;
+                   is_define = 1;
+                   goto insert_if_check_paren;
+               }
+               else if (RExC_parse[0] == 'R') {
+                   RExC_parse++;
+                   parno = 0;
+                   if (RExC_parse[0] >= '1' && RExC_parse[0] <= '9' ) {
+                       parno = atoi(RExC_parse++);
+                       while (isDIGIT(*RExC_parse))
+                           RExC_parse++;
+                   } else if (RExC_parse[0] == '&') {
+                       SV *sv_dat;
+                       RExC_parse++;
+                       sv_dat = reg_scan_name(pRExC_state,
+                           SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
+                       parno = sv_dat ? *((I32 *)SvPVX(sv_dat)) : 0;
+                   }
+                   ret = reganode(pRExC_state,INSUBP,parno); 
+                   goto insert_if_check_paren;
+               }
                else if (RExC_parse[0] >= '1' && RExC_parse[0] <= '9' ) {
                     /* (?(1)...) */
                    char c;
@@ -4551,6 +5220,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                        RExC_parse++;
                     ret = reganode(pRExC_state, GROUPP, parno);
 
+                 insert_if_check_paren:
                    if ((c = *nextchar(pRExC_state)) != ')')
                        vFAIL("Switch condition not recognized");
                  insert_if:
@@ -4564,6 +5234,8 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                    if (flags&HASWIDTH)
                        *flagp |= HASWIDTH;
                    if (c == '|') {
+                       if (is_define) 
+                           vFAIL("(?(DEFINE)....) does not allow branches");
                        lastbr = reganode(pRExC_state, IFTHEN, 0); /* Fake one for optimizer. */
                         regbranch(pRExC_state, &flags, 1,depth+1);
                         REGTAIL(pRExC_state, ret, lastbr);
@@ -4657,14 +5329,20 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            }
        }
        else {                  /* (...) */
+         capturing_parens:
            parno = RExC_npar;
            RExC_npar++;
+           
            ret = reganode(pRExC_state, OPEN, parno);
-           if (!SIZE_ONLY && RExC_seen & REG_SEEN_RECURSE) {
-               DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
-                       "Setting paren #%"IVdf" to %d\n", parno, REG_NODE_NUM(ret)));
-               RExC_parens[parno-1]= ret;
-
+           if (!SIZE_ONLY ){
+               if (!RExC_nestroot) 
+                   RExC_nestroot = parno;
+               if (RExC_seen & REG_SEEN_RECURSE) {
+                   DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
+                       "Setting open paren #%"IVdf" to %d\n", 
+                       (IV)parno, REG_NODE_NUM(ret)));
+                   RExC_open_parens[parno-1]= ret;
+               }
            }
             Set_Node_Length(ret, 1); /* MJD */
             Set_Node_Offset(ret, RExC_parse); /* MJD */
@@ -4730,7 +5408,16 @@ 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,
+                       "Setting close paren #%"IVdf" to %d\n", 
+                       (IV)parno, REG_NODE_NUM(ender)));
+               RExC_close_parens[parno-1]= ender;
+               if (RExC_nestroot == parno) 
+                   RExC_nestroot = 0;
+           }       
             Set_Node_Offset(ender,RExC_parse+1); /* MJD */
             Set_Node_Length(ender,1); /* MJD */
            break;
@@ -4745,11 +5432,18 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            break;
        case 0:
            ender = reg_node(pRExC_state, END);
+           if (!SIZE_ONLY) {
+                assert(!RExC_opend); /* there can only be one! */
+                RExC_opend = ender;
+            }
            break;
        }
-        REGTAIL_STUDY(pRExC_state, lastbr, ender);
+        REGTAIL(pRExC_state, lastbr, ender);
 
        if (have_branch && !SIZE_ONLY) {
+           if (depth==1)
+               RExC_seen |= REG_TOP_LEVEL_BRANCHES;
+
            /* Hook the tails of the branches to the closing node. */
            for (br = ret; br; br = regnext(br)) {
                const U8 op = PL_regkind[OP(br)];
@@ -4982,10 +5676,6 @@ S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
        *flagp = flags;
        return(ret);
     }
-    /* else if (OP(ret)==RECURSE) {
-        RExC_parse++;
-        vFAIL("Illegal quantifier on recursion group");
-    } */
 
 #if 0                          /* Now runtime fix should be reliable. */
 
@@ -5038,12 +5728,27 @@ S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
               origparse);
     }
 
-    if (*RExC_parse == '?') {
+    if (RExC_parse < RExC_end && *RExC_parse == '?') {
        nextchar(pRExC_state);
        reginsert(pRExC_state, MINMOD, ret, depth+1);
         REGTAIL(pRExC_state, ret, ret + NODE_STEP_REGNODE);
     }
-    if (ISMULT2(RExC_parse)) {
+#ifndef REG_ALLOW_MINMOD_SUSPEND
+    else
+#endif
+    if (RExC_parse < RExC_end && *RExC_parse == '+') {
+        regnode *ender;
+        nextchar(pRExC_state);
+        ender = reg_node(pRExC_state, SUCCEED);
+        REGTAIL(pRExC_state, ret, ender);
+        reginsert(pRExC_state, SUSPEND, ret, depth+1);
+        ret->flags = 0;
+        ender = reg_node(pRExC_state, TAIL);
+        REGTAIL(pRExC_state, ret, ender);
+        /*ret= ender;*/
+    }
+
+    if (RExC_parse < RExC_end && ISMULT2(RExC_parse)) {
        RExC_parse++;
        vFAIL("Nested quantifiers");
     }
@@ -5319,6 +6024,39 @@ S_reg_namedseq(pTHX_ RExC_state_t *pRExC_state, UV *valuep)
 }
 
 
+/*
+ * reg_recode
+ *
+ * It returns the code point in utf8 for the value in *encp.
+ *    value: a code value in the source encoding
+ *    encp:  a pointer to an Encode object
+ *
+ * If the result from Encode is not a single character,
+ * it returns U+FFFD (Replacement character) and sets *encp to NULL.
+ */
+STATIC UV
+S_reg_recode(pTHX_ const char value, SV **encp)
+{
+    STRLEN numlen = 1;
+    SV * const sv = sv_2mortal(newSVpvn(&value, numlen));
+    const char * const s = encp && *encp ? sv_recode_to_utf8(sv, *encp)
+                                        : SvPVX(sv);
+    const STRLEN newlen = SvCUR(sv);
+    UV uv = UNICODE_REPLACEMENT;
+
+    if (newlen)
+       uv = SvUTF8(sv)
+            ? utf8n_to_uvchr((U8*)s, newlen, &numlen, UTF8_ALLOW_DEFAULT)
+            : *(U8*)s;
+
+    if (!newlen || numlen != newlen) {
+       uv = UNICODE_REPLACEMENT;
+       if (encp)
+           *encp = NULL;
+    }
+    return uv;
+}
+
 
 /*
  - regatom - the lowest level
@@ -5347,9 +6085,9 @@ tryagain:
     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);
@@ -5359,9 +6097,9 @@ 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);
@@ -5369,7 +6107,7 @@ 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);
@@ -5564,6 +6302,47 @@ tryagain:
             ++RExC_parse;
             ret= reg_namedseq(pRExC_state, NULL); 
             break;
+       case 'k':    /* Handle \k<NAME> and \k'NAME' */
+        {   
+            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;
+           } else {
+               char* name_start = (RExC_parse += 2);
+               U32 num = 0;
+                SV *sv_dat = reg_scan_name(pRExC_state,
+                    SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
+                ch= (ch == '<') ? '>' : '\'';
+                    
+                if (RExC_parse == name_start || *RExC_parse != ch)
+                    vFAIL2("Sequence \\k%c... not terminated",
+                        (ch == '>' ? '<' : ch));
+                
+                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_rxi->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':
@@ -5574,11 +6353,20 @@ tryagain:
        case 'c':
        case '0':
            goto defchar;
+       case 'R': 
        case '1': case '2': case '3': case '4':
        case '5': case '6': case '7': case '8': case '9':
            {
-               const I32 num = atoi(RExC_parse);
-
+               I32 num;
+               bool isrel=(*RExC_parse=='R');
+               if (isrel)
+                   RExC_parse++;
+               num = atoi(RExC_parse);
+                if (isrel) {
+                    num = RExC_cpar - num;
+                    if (num < 1)
+                        vFAIL("Reference to nonexistent or unclosed group");
+                }
                if (num > 9 && num >= RExC_npar)
                    goto defchar;
                else {
@@ -5586,8 +6374,16 @@ tryagain:
                    while (isDIGIT(*RExC_parse))
                        RExC_parse++;
 
-                   if (!SIZE_ONLY && num > (I32)RExC_rx->nparens)
-                       vFAIL("Reference to nonexistent group");
+                   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,
                                   (U8)(FOLD ? (LOC ? REFFL : REFF) : REF),
@@ -5615,7 +6411,7 @@ 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)
@@ -5646,7 +6442,7 @@ tryagain:
            {
                char * const oldp = p;
 
-               if (RExC_flags & PMf_EXTENDED)
+               if (RExC_flags & RXf_PMf_EXTENDED)
                    p = regwhite(p, RExC_end);
                switch (*p) {
                case '^':
@@ -5676,6 +6472,7 @@ tryagain:
                    case 'p':
                    case 'P':
                     case 'N':
+                    case 'R':
                        --p;
                        goto loopdone;
                    case 'n':
@@ -5726,6 +6523,8 @@ tryagain:
                            ender = grok_hex(p, &numlen, &flags, NULL);
                            p += numlen;
                        }
+                       if (PL_encoding && ender < 0x100)
+                           goto recode_encoding;
                        break;
                    case 'c':
                        p++;
@@ -5745,6 +6544,17 @@ tryagain:
                            --p;
                            goto loopdone;
                        }
+                       if (PL_encoding && ender < 0x100)
+                           goto recode_encoding;
+                       break;
+                   recode_encoding:
+                       {
+                           SV* enc = PL_encoding;
+                           ender = reg_recode((const char)(U8)ender, &enc);
+                           if (!enc && SIZE_ONLY && ckWARN(WARN_REGEXP))
+                               vWARN(p, "Invalid escape in the specified encoding");
+                           RExC_utf8 = 1;
+                       }
                        break;
                    case '\0':
                        if (p >= RExC_end)
@@ -5768,7 +6578,7 @@ 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. */
@@ -5872,33 +6682,6 @@ tryagain:
        break;
     }
 
-    /* If the encoding pragma is in effect recode the text of
-     * any EXACT-kind nodes. */
-    if (ret && PL_encoding && PL_regkind[OP(ret)] == EXACT) {
-       const STRLEN oldlen = STR_LEN(ret);
-       SV * const sv = sv_2mortal(newSVpvn(STRING(ret), oldlen));
-
-       if (RExC_utf8)
-           SvUTF8_on(sv);
-       if (sv_utf8_downgrade(sv, TRUE)) {
-           const char * const s = sv_recode_to_utf8(sv, PL_encoding);
-           const STRLEN newlen = SvCUR(sv);
-
-           if (SvUTF8(sv))
-               RExC_utf8 = 1;
-           if (!SIZE_ONLY) {
-               GET_RE_DEBUG_FLAGS_DECL;
-               DEBUG_COMPILE_r(PerlIO_printf(Perl_debug_log, "recode %*s to %*s\n",
-                                     (int)oldlen, STRING(ret),
-                                     (int)newlen, s));
-               Copy(s, STRING(ret), newlen, char);
-               STR_LEN(ret) += newlen - oldlen;
-               RExC_emit += STR_SZ(newlen) - STR_SZ(oldlen);
-           } else
-               RExC_size += STR_SZ(newlen) - STR_SZ(oldlen);
-       }
-    }
-
     return(ret);
 }
 
@@ -6269,6 +7052,8 @@ parseit:
                    value = grok_hex(RExC_parse, &numlen, &flags, NULL);
                    RExC_parse += numlen;
                }
+               if (PL_encoding && value < 0x100)
+                   goto recode_encoding;
                break;
            case 'c':
                value = UCHARAT(RExC_parse++);
@@ -6276,13 +7061,24 @@ parseit:
                break;
            case '0': case '1': case '2': case '3': case '4':
            case '5': case '6': case '7': case '8': case '9':
-            {
-                I32 flags = 0;
-               numlen = 3;
-               value = grok_oct(--RExC_parse, &numlen, &flags, NULL);
-               RExC_parse += numlen;
-               break;
-            }
+               {
+                   I32 flags = 0;
+                   numlen = 3;
+                   value = grok_oct(--RExC_parse, &numlen, &flags, NULL);
+                   RExC_parse += numlen;
+                   if (PL_encoding && value < 0x100)
+                       goto recode_encoding;
+                   break;
+               }
+           recode_encoding:
+               {
+                   SV* enc = PL_encoding;
+                   value = reg_recode((const char)(U8)value, &enc);
+                   if (!enc && SIZE_ONLY && ckWARN(WARN_REGEXP))
+                       vWARN(RExC_parse,
+                             "Invalid escape in the specified encoding");
+                   break;
+               }
            default:
                if (!SIZE_ONLY && isALPHA(value) && ckWARN(WARN_REGEXP))
                    vWARN2(RExC_parse,
@@ -6916,7 +7712,7 @@ 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;
@@ -6938,7 +7734,7 @@ 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;
@@ -6969,6 +7765,11 @@ S_reg_node(pTHX_ RExC_state_t *pRExC_state, U8 op)
        RExC_size += 1;
        return(ret);
     }
+#ifdef DEBUGGING
+    if (OP(RExC_emit) == 255)
+        Perl_croak(aTHX_ "panic: reg_node overrun trying to emit %s: %d ",
+            reg_name[op], OP(RExC_emit));
+#endif  
     NODE_ALIGN_FILL(ret);
     ptr = ret;
     FILL_ADVANCE_NODE(ptr, op);
@@ -6985,7 +7786,6 @@ S_reg_node(pTHX_ RExC_state_t *pRExC_state, U8 op)
     }
 
     RExC_emit = ptr;
-
     return(ret);
 }
 
@@ -7019,7 +7819,10 @@ S_reganode(pTHX_ RExC_state_t *pRExC_state, U8 op, U32 arg)
        */
        return(ret);
     }
-
+#ifdef DEBUGGING
+    if (OP(RExC_emit) == 255)
+        Perl_croak(aTHX_ "panic: reganode overwriting end of allocated program space");
+#endif 
     NODE_ALIGN_FILL(ret);
     ptr = ret;
     FILL_ADVANCE_NODE_ARG(ptr, op, arg);
@@ -7037,7 +7840,6 @@ S_reganode(pTHX_ RExC_state_t *pRExC_state, U8 op, U32 arg)
     }
             
     RExC_emit = ptr;
-
     return(ret);
 }
 
@@ -7076,14 +7878,25 @@ S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *opnd, U32 depth)
     src = RExC_emit;
     RExC_emit += size;
     dst = RExC_emit;
-    if (RExC_parens) {
+    if (RExC_open_parens) {
         int paren;
+        DEBUG_PARSE_FMT("inst"," - %"IVdf, (IV)RExC_npar);
         for ( paren=0 ; paren < RExC_npar ; paren++ ) {
-            if ( RExC_parens[paren] >= src ) 
-                RExC_parens[paren] += size;
-        }            
+            if ( RExC_open_parens[paren] >= opnd ) {
+                DEBUG_PARSE_FMT("open"," - %d",size);
+                RExC_open_parens[paren] += size;
+            } else {
+                DEBUG_PARSE_FMT("open"," - %s","ok");
+            }
+            if ( RExC_close_parens[paren] >= opnd ) {
+                DEBUG_PARSE_FMT("close"," - %d",size);
+                RExC_close_parens[paren] += size;
+            } else {
+                DEBUG_PARSE_FMT("close"," - %s","ok");
+            }
+        }
     }
-    
+
     while (src > opnd) {
        StructCopy(--src, --dst, regnode);
         if (RExC_offsets) {     /* MJD 20010112 */
@@ -7147,8 +7960,11 @@ S_regtail(pTHX_ RExC_state_t *pRExC_state, regnode *p, const regnode *val,U32 de
             SV * const mysv=sv_newmortal();
             DEBUG_PARSE_MSG((scan==p ? "tail" : ""));
             regprop(RExC_rx, mysv, scan);
-            PerlIO_printf(Perl_debug_log, "~ %s (%d)\n",
-                SvPV_nolen_const(mysv), REG_NODE_NUM(scan));
+            PerlIO_printf(Perl_debug_log, "~ %s (%d) %s %s\n",
+                SvPV_nolen_const(mysv), REG_NODE_NUM(scan),
+                    (temp == NULL ? "->" : ""),
+                    (temp == NULL ? reg_name[OP(val)] : "")
+            );
         });
         if (temp == NULL)
             break;
@@ -7225,10 +8041,10 @@ S_regtail_study(pTHX_ RExC_state_t *pRExC_state, regnode *p, const regnode *val,
             SV * const mysv=sv_newmortal();
             DEBUG_PARSE_MSG((scan==p ? "tsdy" : ""));
             regprop(RExC_rx, mysv, scan);
-            PerlIO_printf(Perl_debug_log, "~ %s (%s) (%d)\n",
+            PerlIO_printf(Perl_debug_log, "~ %s (%d) -> %s\n",
                 SvPV_nolen_const(mysv),
-                reg_name[exact],
-                REG_NODE_NUM(scan));
+                REG_NODE_NUM(scan),
+                reg_name[exact]);
         });
        if (temp == NULL)
            break;
@@ -7238,10 +8054,10 @@ 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)]) {
@@ -7287,8 +8103,9 @@ 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) {
@@ -7327,37 +8144,37 @@ 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
@@ -7375,9 +8192,12 @@ 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. */
@@ -7402,14 +8222,14 @@ 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 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] :
+            (reg_trie_data*)progi->data->data[n] :
             ac->trie;
         
         Perl_sv_catpvf(aTHX_ sv, "-%s",reg_name[o->flags]);
@@ -7417,7 +8237,7 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
             Perl_sv_catpvf(aTHX_ sv,
                 "<S:%"UVuf"/%"IVdf" W:%"UVuf" L:%"UVuf"/%"UVuf" C:%"UVuf"/%"UVuf">",
                 (UV)trie->startstate,
-                (IV)trie->laststate-1,
+                (IV)trie->statecount-1, /* -1 because of the unused 0 element */
                 (UV)trie->wordcount,
                 (UV)trie->minlen,
                 (UV)trie->maxlen,
@@ -7456,11 +8276,15 @@ 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) 
+    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 == RECURSE)
+    else if (k == GOSUB) 
        Perl_sv_catpvf(aTHX_ sv, "%d[%+d]", (int)ARG(o),(int)ARG2L(o)); /* Paren and offset */
-    else if (k == LOGICAL)
+    else if (k == VERB) {
+        if (!o->flags) 
+            Perl_sv_catpvf(aTHX_ sv, ":%"SVf, 
+                (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) {
        int i, rangestart = -1;
@@ -7647,7 +8471,7 @@ void
 Perl_pregfree(pTHX_ struct regexp *r)
 {
     dVAR;
-
+    RXi_GET_DECL(r,ri);
     GET_RE_DEBUG_FLAGS_DECL;
 
     if (!r || (--r->refcnt > 0))
@@ -7655,9 +8479,9 @@ Perl_pregfree(pTHX_ struct regexp *r)
     DEBUG_COMPILE_r({
        if (!PL_colorset)
            reginitcolors();
-       if (RX_DEBUG(r)){
-            SV *dsv= sv_newmortal();
-            RE_PV_QUOTED_DECL(s, (r->reganch & ROPT_UTF8),
+       {
+           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);
@@ -7667,7 +8491,7 @@ Perl_pregfree(pTHX_ struct regexp *r)
     /* 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 */
+    Safefree(ri->offsets);             /* 20010421 MJD */
     RX_MATCH_COPY_FREE(r);
 #ifdef PERL_OLD_COPY_ON_WRITE
     if (r->saved_copy)
@@ -7684,23 +8508,26 @@ Perl_pregfree(pTHX_ struct regexp *r)
            SvREFCNT_dec(r->float_utf8);
        Safefree(r->substrs);
     }
-    if (r->data) {
-       int n = r->data->count;
+    if (r->paren_names)
+            SvREFCNT_dec(r->paren_names);
+    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':
-               SvREFCNT_dec((SV*)r->data->data[n]);
+           case 'S':
+               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)
@@ -7710,10 +8537,10 @@ 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);
@@ -7725,17 +8552,18 @@ 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);
+                        PerlMemShared_free(aho->states);
+                        PerlMemShared_free(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);
+                        /* do this last!!!! */
+                        PerlMemShared_free(ri->data->data[n]);
+                        PerlMemShared_free(ri->regstclass);
                     }
                 }
                 break;
@@ -7743,50 +8571,56 @@ 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);
+                        PerlMemShared_free(trie->charmap);
                         if (trie->widecharmap)
                             SvREFCNT_dec((SV*)trie->widecharmap);
-                        Safefree(trie->states);
-                        Safefree(trie->trans);
+                        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);
+                            PerlMemShared_free(trie->nextword);
 #ifdef DEBUGGING
-                        if (RX_DEBUG(r)) {
-                            if (trie->words)
-                                SvREFCNT_dec((SV*)trie->words);
-                            if (trie->revcharmap)
-                                SvREFCNT_dec((SV*)trie->revcharmap);
-                        }
+                        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!!!! */
+                        /* 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 (ri->swap) {
+        Safefree(ri->swap->startp);
+        Safefree(ri->swap->endp);
+        Safefree(ri->swap);
+    }
+    Safefree(ri);
     Safefree(r);
 }
 
 #define sv_dup_inc(s,t)        SvREFCNT_inc(sv_dup(s,t))
 #define av_dup_inc(s,t)        (AV*)SvREFCNT_inc(sv_dup((SV*)s,t))
+#define hv_dup_inc(s,t)        (HV*)SvREFCNT_inc(sv_dup((SV*)s,t))
 #define SAVEPVN(p,n)   ((p) ? savepvn(p,n) : NULL)
 
 /* 
@@ -7803,26 +8637,38 @@ regexp *
 Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
 {
     dVAR;
-    REGEXP *ret;
+    regexp *ret;
+    regexp_internal *reti;
     int i, len, npar;
     struct reg_substr_datum *s;
-
+    RXi_GET_DECL(r,ri);
+    
     if (!r)
        return (REGEXP *)NULL;
 
     if ((ret = (REGEXP *)ptr_table_fetch(PL_ptr_table, r)))
        return ret;
 
-    len = r->offsets[0];
+    len = ri->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);
+    Newxc(reti, sizeof(regexp_internal) + (len+1)*sizeof(regnode), char, regexp_internal);
+    RXi_SET(ret,reti);
+    Copy(ri->program, reti->program, len+1, regnode);
 
     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(ri->swap) {
+        Newx(reti->swap, 1, regexp_paren_ofs);
+        /* no need to copy these */
+        Newx(reti->swap->startp, npar, I32);
+        Newx(reti->swap->endp, npar, I32);
+    } else {
+        reti->swap = NULL;
+    }
 
     Newx(ret->substrs, 1, struct reg_substr_data);
     for (s = ret->substrs->data, i = 0; i < 3; i++, s++) {
@@ -7833,10 +8679,10 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *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 *),
@@ -7845,41 +8691,42 @@ 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: sfpont
+               /* legal options are one of: sSfpontT
                   see also regcomp.h and pregfree() */
            case 's':
-               d->data[i] = sv_dup_inc((SV *)r->data->data[i], param);
+           case 'S':
+               d->data[i] = sv_dup_inc((SV *)ri->data->data[i], param);
                break;
            case 'p':
-               d->data[i] = av_dup_inc((AV *)r->data->data[i], param);
+               d->data[i] = av_dup_inc((AV *)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. */
+               /* Compiled op trees are readonly and in shared memory,
+                  and can thus be shared without duplication. */
                OP_REFCNT_LOCK;
-               d->data[i] = (void*)OpREFCNT_inc((OP*)r->data->data[i]);
+               d->data[i] = (void*)OpREFCNT_inc((OP*)ri->data->data[i]);
                OP_REFCNT_UNLOCK;
                break;
            case 'n':
-               d->data[i] = r->data->data[i];
+               d->data[i] = ri->data->data[i];
                break;
            case 't':
-               d->data[i] = r->data->data[i];
+               d->data[i] = ri->data->data[i];
                OP_REFCNT_LOCK;
                ((reg_trie_data*)d->data[i])->refcount++;
                OP_REFCNT_UNLOCK;
                break;
            case 'T':
-               d->data[i] = r->data->data[i];
+               d->data[i] = ri->data->data[i];
                OP_REFCNT_LOCK;
                ((reg_ac_data*)d->data[i])->refcount++;
                OP_REFCNT_UNLOCK;
@@ -7887,33 +8734,37 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
                 * 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;
                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;
+       reti->data = NULL;
 
-    Newx(ret->offsets, 2*len+1, U32);
-    Copy(r->offsets, ret->offsets, 2*len+1, U32);
+    Newx(reti->offsets, 2*len+1, U32);
+    Copy(ri->offsets, reti->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;
+    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);
@@ -7928,6 +8779,112 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
 }
 #endif    
 
+/* 
+   reg_stringify() 
+   
+   converts a regexp embedded in a MAGIC struct to its stringified form, 
+   caching the converted form in the struct and returns the cached 
+   string. 
+
+   If lp is nonnull then it is used to return the length of the 
+   resulting string
+   
+   If flags is nonnull and the returned string contains UTF8 then 
+   (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);
+        
+   And internally with
+   
+        CALLREG_AS_STR(mg,lp,flags,haseval)        
+    
+   See sv_2pv_flags() in sv.c for an example of internal usage.
+    
+ */
+
+char *
+Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
+    dVAR;
+    const regexp * const re = (regexp *)mg->mg_obj;
+    RXi_GET_DECL(re,ri);
+    
+    if (!mg->mg_ptr) {
+       const char *fptr = "msix";
+       char reflags[6];
+       char ch;
+       int left = 0;
+       int right = 4;
+       bool need_newline = 0;
+       U16 reganch = (U16)((re->extflags & RXf_PMf_COMPILETIME) >> 12);
+
+       while((ch = *fptr++)) {
+           if(reganch & 1) {
+               reflags[left++] = ch;
+           }
+           else {
+               reflags[right--] = ch;
+           }
+           reganch >>= 1;
+       }
+       if(left != 4) {
+           reflags[left] = '-';
+           left = 5;
+       }
+
+       mg->mg_len = re->prelen + 4 + left;
+       /*
+        * If /x was used, we have to worry about a regex ending with a
+        * comment later being embedded within another regex. If so, we don't
+        * want this regex's "commentization" to leak out to the right part of
+        * the enclosing regex, we must cap it with a newline.
+        *
+        * So, if /x was used, we scan backwards from the end of the regex. If
+        * we find a '#' before we find a newline, we need to add a newline
+        * 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->extflags) {
+           const char *endptr = re->precomp + re->prelen;
+           while (endptr >= re->precomp) {
+               const char c = *(endptr--);
+               if (c == '\n')
+                   break; /* don't need another */
+               if (c == '#') {
+                   /* we end while in a comment, so we need a newline */
+                   mg->mg_len++; /* save space for it */
+                   need_newline = 1; /* note to add it */
+                   break;
+               }
+           }
+       }
+
+       Newx(mg->mg_ptr, mg->mg_len + 1 + left, char);
+       mg->mg_ptr[0] = '(';
+       mg->mg_ptr[1] = '?';
+       Copy(reflags, mg->mg_ptr+2, left, char);
+       *(mg->mg_ptr+left+2) = ':';
+       Copy(re->precomp, mg->mg_ptr+3+left, re->prelen, char);
+       if (need_newline)
+           mg->mg_ptr[mg->mg_len - 2] = '\n';
+       mg->mg_ptr[mg->mg_len - 1] = ')';
+       mg->mg_ptr[mg->mg_len] = 0;
+    }
+    if (haseval) 
+        *haseval = ri->program[0].next_off;
+    if (flags)    
+       *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
@@ -7938,7 +8895,7 @@ 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));
@@ -8059,7 +9016,7 @@ 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
 
@@ -8074,6 +9031,7 @@ 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
@@ -8089,7 +9047,7 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
 
        NODE_ALIGN(node);
        op = OP(node);
-       if (op == CLOSE)
+       if (op == CLOSE || op == WHILEM)
            indent--;
        next = regnext((regnode *)node);
        
@@ -8135,13 +9093,14 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
            DUMPUNTIL(NEXTOPER(node), next);
        }
        else if ( PL_regkind[(U8)op]  == TRIE ) {
+           const regnode *this_trie = node;
            const char op = OP(node);
             const I32 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] :
+               (reg_trie_data*)ri->data->data[n] :
                ac->trie;
            const regnode *nextbranch= NULL;
            I32 word_idx;
@@ -8155,18 +9114,19 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
                            PL_colors[0], PL_colors[1],
                            (SvUTF8(*elem_ptr) ? PERL_PV_ESCAPE_UNI : 0) |
                            PERL_PV_PRETTY_ELIPSES    |
-                           PERL_PV_PRETTY_LTGT    
+                           PERL_PV_PRETTY_LTGT
                             )
                             : "???"
                 );
                 if (trie->jump) {
                     U16 dist= trie->jump[word_idx+1];
-                    PerlIO_printf(Perl_debug_log, "(%u)\n",(next - dist) - start);
+                   PerlIO_printf(Perl_debug_log, "(%"UVuf")\n",
+                                 (UV)((dist ? this_trie + dist : next) - start));
                     if (dist) {
                         if (!nextbranch)
-                            nextbranch= next - trie->jump[0];
-                        DUMPUNTIL(next - dist, nextbranch);
-                    } 
+                            nextbranch= this_trie + trie->jump[0];    
+                       DUMPUNTIL(this_trie + dist, nextbranch);
+                    }
                     if (nextbranch && PL_regkind[OP(nextbranch)]==BRANCH)
                         nextbranch= regnext((regnode *)nextbranch);
                 } else {
@@ -8206,12 +9166,10 @@ 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;
 }