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Re: [perl #41010] (?(COND)) in pattern matching not working properly
[perl5.git] / regcomp.c
index e3f7ee0..359e4f6 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. */
@@ -142,11 +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)
@@ -154,7 +156,6 @@ typedef struct RExC_state_t {
 #define RExC_seen      (pRExC_state->seen)
 #define RExC_size      (pRExC_state->size)
 #define RExC_npar      (pRExC_state->npar)
-#define RExC_cpar      (pRExC_state->cpar)
 #define RExC_nestroot   (pRExC_state->nestroot)
 #define RExC_extralen  (pRExC_state->extralen)
 #define RExC_seen_zerolen      (pRExC_state->seen_zerolen)
@@ -555,17 +556,18 @@ static const scan_data_t zero_scan_data =
 #define EXPERIMENTAL_INPLACESCAN
 #endif
 
-#define DEBUG_STUDYDATA(data,depth)                                  \
-DEBUG_OPTIMISE_MORE_r(if(data){                                           \
+#define DEBUG_STUDYDATA(str,data,depth)                              \
+DEBUG_OPTIMISE_MORE_r(if(data){                                      \
     PerlIO_printf(Perl_debug_log,                                    \
-        "%*s"/* Len:%"IVdf"/%"IVdf" */"Pos:%"IVdf"/%"IVdf           \
-        " Flags: %"IVdf" Whilem_c: %"IVdf" Lcp: %"IVdf" ",           \
+        "%*s" str "Pos:%"IVdf"/%"IVdf                                \
+        " Flags: 0x%"UVXf" Whilem_c: %"IVdf" Lcp: %"IVdf" %s",       \
         (int)(depth)*2, "",                                          \
         (IV)((data)->pos_min),                                       \
         (IV)((data)->pos_delta),                                     \
-        (IV)((data)->flags),                                         \
+        (UV)((data)->flags),                                         \
         (IV)((data)->whilem_c),                                      \
-        (IV)((data)->last_closep ? *((data)->last_closep) : -1)      \
+        (IV)((data)->last_closep ? *((data)->last_closep) : -1),     \
+        is_inf ? "INF " : ""                                         \
     );                                                               \
     if ((data)->last_found)                                          \
         PerlIO_printf(Perl_debug_log,                                \
@@ -595,7 +597,7 @@ static void clear_re(pTHX_ void *r);
    floating substrings if needed. */
 
 STATIC void
-S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *minlenp)
+S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *minlenp, int is_inf)
 {
     const STRLEN l = CHR_SVLEN(data->last_found);
     const STRLEN old_l = CHR_SVLEN(*data->longest);
@@ -613,12 +615,12 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *min
            data->minlen_fixed=minlenp; 
            data->lookbehind_fixed=0;
        }
-       else {
+       else { /* *data->longest == data->longest_float */
            data->offset_float_min = l ? data->last_start_min : data->pos_min;
            data->offset_float_max = (l
                                      ? data->last_start_max
                                      : data->pos_min + data->pos_delta);
-           if ((U32)data->offset_float_max > (U32)I32_MAX)
+           if (is_inf || (U32)data->offset_float_max > (U32)I32_MAX)
                data->offset_float_max = I32_MAX;
            if (data->flags & SF_BEFORE_EOL)
                data->flags
@@ -640,7 +642,7 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *min
     }
     data->last_end = -1;
     data->flags &= ~SF_BEFORE_EOL;
-    DEBUG_STUDYDATA(data,0);
+    DEBUG_STUDYDATA("cl_anything: ",data,0);
 }
 
 /* Can match anything (initialization) */
@@ -796,9 +798,9 @@ S_cl_or(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, con
 
 #ifdef DEBUGGING
 /*
-   dump_trie(trie)
-   dump_trie_interim_list(trie,next_alloc)
-   dump_trie_interim_table(trie,next_alloc)
+   dump_trie(trie,widecharmap,revcharmap)
+   dump_trie_interim_list(trie,widecharmap,revcharmap,next_alloc)
+   dump_trie_interim_table(trie,widecharmap,revcharmap,next_alloc)
 
    These routines dump out a trie in a somewhat readable format.
    The _interim_ variants are used for debugging the interim
@@ -811,17 +813,17 @@ S_cl_or(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, con
 */
 
 /*
-  dump_trie(trie)
   Dumps the final compressed table form of the trie to Perl_debug_log.
   Used for debugging make_trie().
 */
  
 STATIC void
-S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
+S_dump_trie(pTHX_ const struct _reg_trie_data *trie, HV *widecharmap,
+           AV *revcharmap, U32 depth)
 {
     U32 state;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
 
 
@@ -830,7 +832,7 @@ S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
         "Match","Base","Ofs" );
 
     for( state = 0 ; state < trie->uniquecharcount ; state++ ) {
-       SV ** const tmp = av_fetch( trie->revcharmap, state, 0);
+       SV ** const tmp = av_fetch( revcharmap, state, 0);
         if ( tmp ) {
             PerlIO_printf( Perl_debug_log, "%*s", 
                 colwidth,
@@ -892,18 +894,19 @@ S_dump_trie(pTHX_ const struct _reg_trie_data *trie,U32 depth)
     }
 }    
 /*
-  dump_trie_interim_list(trie,next_alloc)
   Dumps a fully constructed but uncompressed trie in list form.
   List tries normally only are used for construction when the number of 
   possible chars (trie->uniquecharcount) is very high.
   Used for debugging make_trie().
 */
 STATIC void
-S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc,U32 depth)
+S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie,
+                        HV *widecharmap, AV *revcharmap, U32 next_alloc,
+                        U32 depth)
 {
     U32 state;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
     /* print out the table precompression.  */
     PerlIO_printf( Perl_debug_log, "%*sState :Word | Transition Data\n%*s%s",
@@ -923,7 +926,7 @@ S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc
             );
         }
         for( charid = 1 ; charid <= TRIE_LIST_USED( state ) ; charid++ ) {
-           SV ** const tmp = av_fetch( trie->revcharmap, TRIE_LIST_ITEM(state,charid).forid, 0);
+           SV ** const tmp = av_fetch( revcharmap, TRIE_LIST_ITEM(state,charid).forid, 0);
            if ( tmp ) {
                 PerlIO_printf( Perl_debug_log, "%*s:%3X=%4"UVXf" | ",
                     colwidth,
@@ -945,19 +948,20 @@ S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc
 }    
 
 /*
-  dump_trie_interim_table(trie,next_alloc)
   Dumps a fully constructed but uncompressed trie in table form.
   This is the normal DFA style state transition table, with a few 
   twists to facilitate compression later. 
   Used for debugging make_trie().
 */
 STATIC void
-S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie, U32 next_alloc, U32 depth)
+S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie,
+                         HV *widecharmap, AV *revcharmap, U32 next_alloc,
+                         U32 depth)
 {
     U32 state;
     U16 charid;
     SV *sv=sv_newmortal();
-    int colwidth= trie->widecharmap ? 6 : 4;
+    int colwidth= widecharmap ? 6 : 4;
     GET_RE_DEBUG_FLAGS_DECL;
     
     /*
@@ -968,7 +972,7 @@ S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie, U32 next_allo
     PerlIO_printf( Perl_debug_log, "%*sChar : ",(int)depth * 2 + 2,"" );
 
     for( charid = 0 ; charid < trie->uniquecharcount ; charid++ ) {
-       SV ** const tmp = av_fetch( trie->revcharmap, charid, 0);
+       SV ** const tmp = av_fetch( revcharmap, charid, 0);
         if ( tmp ) {
             PerlIO_printf( Perl_debug_log, "%*s", 
                 colwidth,
@@ -1135,7 +1139,7 @@ is the recommended Unicode-aware way of saying
        SV *tmp = newSVpvs("");                                            \
        if (UTF) SvUTF8_on(tmp);                                           \
        Perl_sv_catpvf( aTHX_ tmp, "%c", (int)uvc );                       \
-       av_push( TRIE_REVCHARMAP(trie), tmp );                             \
+       av_push( revcharmap, tmp );                                        \
     } STMT_END
 
 #define TRIE_READ_CHAR STMT_START {                                           \
@@ -1195,14 +1199,14 @@ is the recommended Unicode-aware way of saying
         else                                                    \
             tmp = newSVpvn( "", 0 );                            \
         if ( UTF ) SvUTF8_on( tmp );                            \
-        av_push( trie->words, tmp );                            \
+        av_push( trie_words, tmp );                             \
     });                                                         \
                                                                 \
     curword++;                                                  \
                                                                 \
     if ( noper_next < tail ) {                                  \
         if (!trie->jump)                                        \
-            Newxz( trie->jump, word_count + 1, U16);            \
+            trie->jump = PerlMemShared_calloc( word_count + 1, sizeof(U16) ); \
         trie->jump[curword] = (U16)(noper_next - convert);      \
         if (!jumper)                                            \
             jumper = noper_next;                                \
@@ -1216,7 +1220,8 @@ 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;                          \
@@ -1246,6 +1251,8 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     dVAR;
     /* first pass, loop through and scan words */
     reg_trie_data *trie;
+    HV *widecharmap = NULL;
+    AV *revcharmap = newAV();
     regnode *cur;
     const U32 uniflags = UTF8_ALLOW_DEFAULT;
     STRLEN len = 0;
@@ -1264,32 +1271,33 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                          )
                      );
 
-    const U32 data_slot = add_data( pRExC_state, 1, "t" );
-    SV *re_trie_maxbuff;
-#ifndef DEBUGGING
-    /* these are only used during construction but are useful during
-     * debugging so we store them in the struct when debugging.
+#ifdef DEBUGGING
+    const U32 data_slot = add_data( pRExC_state, 4, "tuuu" );
+    AV *trie_words = NULL;
+    /* along with revcharmap, this only used during construction but both are
+     * useful during debugging so we store them in the struct when debugging.
      */
+#else
+    const U32 data_slot = add_data( pRExC_state, 2, "tu" );
     STRLEN trie_charcount=0;
-    AV *trie_revcharmap;
 #endif
+    SV *re_trie_maxbuff;
     GET_RE_DEBUG_FLAGS_DECL;
 #ifndef DEBUGGING
     PERL_UNUSED_ARG(depth);
 #endif
 
-    Newxz( trie, 1, reg_trie_data );
+    trie = 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();
+        trie_words = newAV();
     });
-    TRIE_REVCHARMAP(trie) = newAV();
 
     re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
     if (!SvIOK(re_trie_maxbuff)) {
@@ -1367,10 +1375,10 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                 }
             } else {
                 SV** svpp;
-                if ( !trie->widecharmap )
-                    trie->widecharmap = newHV();
+                if ( !widecharmap )
+                    widecharmap = newHV();
 
-                svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 1 );
+                svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 1 );
 
                 if ( !svpp )
                     Perl_croak( aTHX_ "error creating/fetching widecharmap entry for 0x%"UVXf, uvc );
@@ -1394,11 +1402,11 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
     DEBUG_TRIE_COMPILE_r(
         PerlIO_printf( Perl_debug_log, "%*sTRIE(%s): W:%d C:%d Uq:%d Min:%d Max:%d\n",
                 (int)depth * 2 + 2,"",
-                ( trie->widecharmap ? "UTF8" : "NATIVE" ), (int)word_count,
+                ( widecharmap ? "UTF8" : "NATIVE" ), (int)word_count,
                (int)TRIE_CHARCOUNT(trie), trie->uniquecharcount,
                (int)trie->minlen, (int)trie->maxlen )
     );
-    Newxz( trie->wordlen, word_count, U32 );
+    trie->wordlen = PerlMemShared_calloc( word_count, sizeof(U32) );
 
     /*
         We now know what we are dealing with in terms of unique chars and
@@ -1440,8 +1448,9 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
             "%*sCompiling trie using list compiler\n",
             (int)depth * 2 + 2, ""));
-
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+       
+       trie->states = PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
+                                            sizeof(reg_trie_state) );
         TRIE_LIST_NEW(1);
         next_alloc = 2;
 
@@ -1465,7 +1474,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                     if ( uvc < 256 ) {
                         charid = trie->charmap[ uvc ];
                    } else {
-                        SV** const svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 0);
+                        SV** const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
                         if ( !svpp ) {
                             charid = 0;
                         } else {
@@ -1505,14 +1514,17 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
 
         /* next alloc is the NEXT state to be allocated */
         trie->statecount = next_alloc; 
-        Renew( trie->states, next_alloc, reg_trie_state );
+        trie->states = PerlMemShared_realloc( trie->states, next_alloc
+                                             * sizeof(reg_trie_state) );
 
         /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(
-            dump_trie_interim_list(trie,next_alloc,depth+1)
+        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_list(trie, widecharmap,
+                                                        revcharmap, next_alloc,
+                                                        depth+1)
         );
 
-        Newxz( trie->trans, transcount ,reg_trie_trans );
+        trie->trans
+           = PerlMemShared_calloc( transcount, sizeof(reg_trie_trans) );
         {
             U32 state;
             U32 tp = 0;
@@ -1543,7 +1555,10 @@ 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;
@@ -1623,9 +1638,11 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             "%*sCompiling trie using table compiler\n",
             (int)depth * 2 + 2, ""));
 
-        Newxz( trie->trans, ( TRIE_CHARCOUNT(trie) + 1 ) * trie->uniquecharcount + 1,
-              reg_trie_trans );
-        Newxz( trie->states, TRIE_CHARCOUNT(trie) + 2, reg_trie_state );
+       trie->trans = 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;
 
 
@@ -1653,7 +1670,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                     if ( uvc < 256 ) {
                         charid = trie->charmap[ uvc ];
                     } else {
-                        SV* const * const svpp = hv_fetch( trie->widecharmap, (char*)&uvc, sizeof( UV ), 0);
+                        SV* const * const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
                         charid = svpp ? (U16)SvIV(*svpp) : 0;
                     }
                     if ( charid ) {
@@ -1676,9 +1693,9 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         } /* end second pass */
 
         /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(
-            dump_trie_interim_table(trie,next_alloc,depth+1)
-        );
+        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_table(trie, widecharmap,
+                                                         revcharmap,
+                                                         next_alloc, depth+1));
 
         {
         /*
@@ -1782,7 +1799,8 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             }
         }
         trie->lasttrans = pos + 1;
-        Renew( trie->states, laststate, reg_trie_state);
+        trie->states = 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",
@@ -1802,12 +1820,11 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                 (UV)trie->lasttrans)
     );
     /* resize the trans array to remove unused space */
-    Renew( trie->trans, trie->lasttrans, reg_trie_trans);
+    trie->trans = PerlMemShared_realloc( trie->trans, trie->lasttrans
+                                        * sizeof(reg_trie_trans) );
 
     /* and now dump out the compressed format */
-    DEBUG_TRIE_COMPILE_r(
-        dump_trie(trie,depth+1)
-    );
+    DEBUG_TRIE_COMPILE_r(dump_trie(trie, widecharmap, revcharmap, depth+1));
 
     {   /* Modify the program and insert the new TRIE node*/ 
         U8 nodetype =(U8)(flags & 0xFF);
@@ -1852,7 +1869,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
         /* But first we check to see if there is a common prefix we can 
            split out as an EXACT and put in front of the TRIE node.  */
         trie->startstate= 1;
-        if ( trie->bitmap && !trie->widecharmap && !trie->jump  ) {
+        if ( trie->bitmap && !widecharmap && !trie->jump  ) {
             U32 state;
             for ( state = 1 ; state < trie->statecount-1 ; state++ ) {
                 U32 ofs = 0;
@@ -1869,7 +1886,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                          trie->trans[ base + ofs - trie->uniquecharcount ].check == state )
                     {
                         if ( ++count > 1 ) {
-                            SV **tmp = av_fetch( TRIE_REVCHARMAP(trie), ofs, 0);
+                            SV **tmp = av_fetch( revcharmap, ofs, 0);
                            const U8 *ch = (U8*)SvPV_nolen_const( *tmp );
                             if ( state == 1 ) break;
                             if ( count == 2 ) {
@@ -1880,7 +1897,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                                         (int)depth * 2 + 2, "",
                                         (UV)state));
                                if (idx >= 0) {
-                                   SV ** const tmp = av_fetch( TRIE_REVCHARMAP(trie), idx, 0);
+                                   SV ** const tmp = av_fetch( revcharmap, idx, 0);
                                    const U8 * const ch = (U8*)SvPV_nolen_const( *tmp );
 
                                     TRIE_BITMAP_SET(trie,*ch);
@@ -1900,7 +1917,7 @@ 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);
+                    SV **tmp = av_fetch( revcharmap, idx, 0);
                     char *ch = SvPV_nolen( *tmp );
                     DEBUG_OPTIMISE_r({
                         SV *sv=sv_newmortal();
@@ -1948,7 +1965,7 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
                         Set_Node_Offset_Length(fix, 0, 0);
                     }
                     while (word--) {
-                        SV ** const tmp = av_fetch( trie->words, word, 0 );
+                        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));
@@ -1982,7 +1999,7 @@ 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;
@@ -2016,8 +2033,12 @@ S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *firs
             Set_Node_Offset_Length(convert,mjd_offset,mjd_nodelen);
         });
     } /* end node insert */
-#ifndef DEBUGGING
-    SvREFCNT_dec(TRIE_REVCHARMAP(trie));
+    RExC_rxi->data->data[ data_slot + 1 ] = (void*)widecharmap;
+#ifdef DEBUGGING
+    RExC_rxi->data->data[ data_slot + TRIE_WORDS_OFFSET ] = (void*)trie_words;
+    RExC_rxi->data->data[ data_slot + 3 ] = (void*)revcharmap;
+#else
+    SvREFCNT_dec(revcharmap);
 #endif
     return trie->jump 
            ? MADE_JUMP_TRIE 
@@ -2047,7 +2068,8 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
    try 'g' and succeed, prodceding to match 'cdgu'.
  */
  /* add a fail transition */
-    reg_trie_data *trie=(reg_trie_data *)RExC_rx->data->data[ARG(source)];
+    const U32 trie_offset = ARG(source);
+    reg_trie_data *trie=(reg_trie_data *)RExC_rxi->data->data[trie_offset];
     U32 *q;
     const U32 ucharcount = trie->uniquecharcount;
     const U32 numstates = trie->statecount;
@@ -2066,13 +2088,13 @@ S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode
 
 
     ARG_SET( stclass, data_slot );
-    Newxz( aho, 1, reg_ac_data );
-    RExC_rx->data->data[ data_slot ] = (void*)aho;
-    aho->trie=trie;
-    aho->states=(reg_trie_state *)savepvn((const char*)trie->states,
-        numstates * sizeof(reg_trie_state));
+    aho = PerlMemShared_calloc( 1, sizeof(reg_ac_data) );
+    RExC_rxi->data->data[ data_slot ] = (void*)aho;
+    aho->trie=trie_offset;
+    aho->states=(reg_trie_state *)PerlMemShared_malloc( numstates * sizeof(reg_trie_state) );
+    Copy( trie->states, aho->states, numstates, reg_trie_state );
     Newxz( q, numstates, U32);
-    Newxz( aho->fail, numstates, U32 );
+    aho->fail = PerlMemShared_calloc( numstates, sizeof(U32) );
     aho->refcount = 1;
     fail = aho->fail;
     /* initialize fail[0..1] to be 1 so that we always have
@@ -2326,6 +2348,9 @@ typedef struct scan_frame {
     I32 stop; /* what stopparen do we use */
 } scan_frame;
 
+
+#define SCAN_COMMIT(s, data, m) scan_commit(s, data, m, is_inf)
+
 STATIC I32
 S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                         I32 *minlenp, I32 *deltap,
@@ -2371,7 +2396,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
   fake_study_recurse:
     while ( scan && OP(scan) != END && scan < last ){
        /* Peephole optimizer: */
-       DEBUG_STUDYDATA(data,depth);
+       DEBUG_STUDYDATA("Peep:", data,depth);
        DEBUG_PEEP("Peep",scan,depth);
         JOIN_EXACT(scan,&min,0);
 
@@ -2417,7 +2442,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                regnode * const startbranch=scan;
                
                if (flags & SCF_DO_SUBSTR)
-                   scan_commit(pRExC_state, data, minlenp); /* Cannot merge strings after this. */
+                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot merge strings after this. */
                if (flags & SCF_DO_STCLASS)
                    cl_init_zero(pRExC_state, &accum);
 
@@ -2727,7 +2752,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     end   = RExC_close_parens[paren-1];
                 } else {
                     paren = 0;
-                    start = RExC_rx->program + 1;
+                    start = RExC_rxi->program + 1;
                     end   = RExC_opend;
                 }
                 if (!recursed) {
@@ -2739,7 +2764,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     Newx(newframe,1,scan_frame);
                 } else {
                     if (flags & SCF_DO_SUBSTR) {
-                        scan_commit(pRExC_state,data,minlenp);
+                        SCAN_COMMIT(pRExC_state,data,minlenp);
                         data->longest = &(data->longest_float);
                     }
                     is_inf = is_inf_internal = 1;
@@ -2841,7 +2866,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
            /* Search for fixed substrings supports EXACT only. */
            if (flags & SCF_DO_SUBSTR) {
                assert(data);
-               scan_commit(pRExC_state, data, minlenp);
+               SCAN_COMMIT(pRExC_state, data, minlenp);
            }
            if (UTF) {
                const U8 * const s = (U8 *)STRING(scan);
@@ -2920,7 +2945,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                is_inf = is_inf_internal = 1;
                scan = regnext(scan);
                if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state, data, minlenp); /* Cannot extend fixed substrings */
+                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot extend fixed substrings */
                    data->longest = &(data->longest_float);
                }
                goto optimize_curly_tail;
@@ -2943,7 +2968,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                next_is_eval = (OP(scan) == EVAL);
              do_curly:
                if (flags & SCF_DO_SUBSTR) {
-                   if (mincount == 0) scan_commit(pRExC_state,data,minlenp); /* Cannot extend fixed substrings */
+                   if (mincount == 0) SCAN_COMMIT(pRExC_state,data,minlenp); /* Cannot extend fixed substrings */
                    pos_before = data->pos_min;
                }
                if (data) {
@@ -3214,7 +3239,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    if (mincount != maxcount) {
                         /* Cannot extend fixed substrings found inside
                            the group.  */
-                       scan_commit(pRExC_state,data,minlenp);
+                       SCAN_COMMIT(pRExC_state,data,minlenp);
                        if (mincount && last_str) {
                            SV * const sv = data->last_found;
                            MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
@@ -3246,7 +3271,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                continue;
            default:                    /* REF and CLUMP only? */
                if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);      /* Cannot expect anything... */
+                   SCAN_COMMIT(pRExC_state,data,minlenp);      /* Cannot expect anything... */
                    data->longest = &(data->longest_float);
                }
                is_inf = is_inf_internal = 1;
@@ -3260,7 +3285,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
            int value = 0;
 
            if (flags & SCF_DO_SUBSTR) {
-               scan_commit(pRExC_state,data,minlenp);
+               SCAN_COMMIT(pRExC_state,data,minlenp);
                data->pos_min++;
            }
            min++;
@@ -3549,7 +3574,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     if ((flags & SCF_DO_SUBSTR) && data->last_found) {
                         f |= SCF_DO_SUBSTR;
                         if (scan->flags) 
-                            scan_commit(pRExC_state, &data_fake,minlenp);
+                            SCAN_COMMIT(pRExC_state, &data_fake,minlenp);
                         data_fake.last_found=newSVsv(data->last_found);
                     }
                 }
@@ -3600,7 +3625,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                     if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) {
                         if (RExC_rx->minlen<*minnextp)
                             RExC_rx->minlen=*minnextp;
-                        scan_commit(pRExC_state, &data_fake, minnextp);
+                        SCAN_COMMIT(pRExC_state, &data_fake, minnextp);
                         SvREFCNT_dec(data_fake.last_found);
                         
                         if ( data_fake.minlen_fixed != minlenp ) 
@@ -3646,7 +3671,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
        }
        else if ( PL_regkind[OP(scan)] == ENDLIKE ) {
            if (flags & SCF_DO_SUBSTR) {
-               scan_commit(pRExC_state,data,minlenp);
+               SCAN_COMMIT(pRExC_state,data,minlenp);
                flags &= ~SCF_DO_SUBSTR;
            }
            if (data && OP(scan)==ACCEPT) {
@@ -3658,7 +3683,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
        else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */
        {
                if (flags & SCF_DO_SUBSTR) {
-                   scan_commit(pRExC_state,data,minlenp);
+                   SCAN_COMMIT(pRExC_state,data,minlenp);
                    data->longest = &(data->longest_float);
                }
                is_inf = is_inf_internal = 1;
@@ -3687,12 +3712,12 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                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;
 
             if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
-                scan_commit(pRExC_state, data,minlenp); /* Cannot merge strings after this. */
+                SCAN_COMMIT(pRExC_state, data,minlenp); /* Cannot merge strings after this. */
             if (flags & SCF_DO_STCLASS)
                 cl_init_zero(pRExC_state, &accum);
                 
@@ -3802,14 +3827,14 @@ 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;
            delta += (trie->maxlen - trie->minlen);
            flags &= ~SCF_DO_STCLASS; /* xxx */
             if (flags & SCF_DO_SUBSTR) {
-               scan_commit(pRExC_state,data,minlenp);  /* Cannot expect anything... */
+               SCAN_COMMIT(pRExC_state,data,minlenp);  /* Cannot expect anything... */
                data->pos_min += trie->minlen;
                data->pos_delta += (trie->maxlen - trie->minlen);
                if (trie->maxlen != trie->minlen)
@@ -3833,6 +3858,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
 
   finish:
     assert(!frame);
+    DEBUG_STUDYDATA("pre-fin:",data,depth);
 
     *scanp = scan;
     *deltap = is_inf_internal ? I32_MAX : delta;
@@ -3853,32 +3879,29 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
     if (flags & SCF_TRIE_RESTUDY)
         data->flags |=         SCF_TRIE_RESTUDY;
     
-    DEBUG_STUDYDATA(data,depth);
+    DEBUG_STUDYDATA("post-fin:",data,depth);
     
     return min < stopmin ? min : stopmin;
 }
 
-STATIC I32
-S_add_data(RExC_state_t *pRExC_state, I32 n, const char *s)
+STATIC U32
+S_add_data(RExC_state_t *pRExC_state, U32 n, const char *s)
 {
-    if (RExC_rx->data) {
-       const U32 count = RExC_rx->data->count;
-       Renewc(RExC_rx->data,
-              sizeof(*RExC_rx->data) + sizeof(void*) * (count + n - 1),
-              char, struct reg_data);
-       Renew(RExC_rx->data->what, count + n, U8);
-       RExC_rx->data->count += n;
-    }
-    else {
-       Newxc(RExC_rx->data, sizeof(*RExC_rx->data) + sizeof(void*) * (n - 1),
-            char, struct reg_data);
-       Newx(RExC_rx->data->what, n, U8);
-       RExC_rx->data->count = n;
-    }
-    Copy(s, RExC_rx->data->what + RExC_rx->data->count - n, n, U8);
-    return RExC_rx->data->count - n;
+    U32 count = RExC_rxi->data ? RExC_rxi->data->count : 0;
+
+    Renewc(RExC_rxi->data,
+          sizeof(*RExC_rxi->data) + sizeof(void*) * (count + n - 1),
+          char, struct reg_data);
+    if(count)
+       Renew(RExC_rxi->data->what, count + n, U8);
+    else
+       Newx(RExC_rxi->data->what, n, U8);
+    RExC_rxi->data->count = count + n;
+    Copy(s, RExC_rxi->data->what + count, n, U8);
+    return count;
 }
 
+/*XXX: todo make this not included in a non debugging perl */
 #ifndef PERL_IN_XSUB_RE
 void
 Perl_reginitcolors(pTHX)
@@ -3972,6 +3995,7 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
 #endif
     BEGIN_BLOCK    
     register regexp *r;
+    register regexp_internal *ri;
     regnode *scan;
     regnode *first;
     I32 flags;
@@ -4012,7 +4036,6 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_end = xend;
     RExC_naughty = 0;
     RExC_npar = 1;
-    RExC_cpar = 1;
     RExC_nestroot = 0;
     RExC_size = 0L;
     RExC_emit = &PL_regdummy;
@@ -4059,19 +4082,21 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     /* Allocate space and zero-initialize. Note, the two step process 
        of zeroing when in debug mode, thus anything assigned has to 
        happen after that */
-    Newxc(r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode),
-        char, regexp);
-    if (r == NULL)
+    Newxz(r, 1, regexp);
+    Newxc(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode),
+        char, regexp_internal);
+    if ( r == NULL || ri == NULL )
        FAIL("Regexp out of space");
 #ifdef DEBUGGING
     /* avoid reading uninitialized memory in DEBUGGING code in study_chunk() */
-    Zero(r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode), char);
+    Zero(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode), char);
 #else 
-    /* bulk initialize fields with 0. */
-    Zero(r, sizeof(regexp), char);        
+    /* bulk initialize base fields with 0. */
+    Zero(ri, sizeof(regexp_internal), char);        
 #endif
 
     /* non-zero initialization begins here */
+    RXi_SET( r, ri );
     r->engine= RE_ENGINE_PTR;
     r->refcnt = 1;
     r->prelen = xend - exp;
@@ -4088,16 +4113,17 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     }
 
     /* Useful during FAIL. */
-    Newxz(r->offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
-    if (r->offsets) {
-       r->offsets[0] = RExC_size;
+    Newxz(ri->offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
+    if (ri->offsets) {
+       ri->offsets[0] = RExC_size;
     }
     DEBUG_OFFSETS_r(PerlIO_printf(Perl_debug_log,
                           "%s %"UVuf" bytes for offset annotations.\n",
-                          r->offsets ? "Got" : "Couldn't get",
+                          ri->offsets ? "Got" : "Couldn't get",
                           (UV)((2*RExC_size+1) * sizeof(U32))));
 
     RExC_rx = r;
+    RExC_rxi = ri;
 
     /* Second pass: emit code. */
     RExC_flags = pm->op_pmflags;       /* don't let top level (?i) bleed */
@@ -4105,18 +4131,16 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
     RExC_end = xend;
     RExC_naughty = 0;
     RExC_npar = 1;
-    RExC_cpar = 1;
-    RExC_emit_start = r->program;
-    RExC_emit = r->program;
+    RExC_emit_start = ri->program;
+    RExC_emit = ri->program;
 #ifdef DEBUGGING
     /* put a sentinal on the end of the program so we can check for
        overwrites */
-    r->program[RExC_size].type = 255;
+    ri->program[RExC_size].type = 255;
 #endif
     /* Store the count of eval-groups for security checks: */
-    RExC_emit->next_off = (RExC_seen_evals > (I32)U16_MAX) ? U16_MAX : (U16)RExC_seen_evals;
+    RExC_rx->seen_evals = RExC_seen_evals;
     REGC((U8)REG_MAGIC, (char*) RExC_emit++);
-    r->data = 0;
     if (reg(pRExC_state, 0, &flags,1) == NULL)
        return(NULL);
 
@@ -4161,10 +4185,10 @@ reStudy:
     pm->op_pmflags = RExC_flags;
     if (UTF)
         r->extflags |= RXf_UTF8;       /* Unicode in it? */
-    r->regstclass = NULL;
+    ri->regstclass = NULL;
     if (RExC_naughty >= 10)    /* Probably an expensive pattern. */
        r->intflags |= PREGf_NAUGHTY;
-    scan = r->program + 1;             /* First BRANCH. */
+    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 */
@@ -4207,35 +4231,35 @@ 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->extflags |= (OP(first) == MBOL
                           ? RXf_ANCH_MBOL
@@ -4302,7 +4326,7 @@ reStudy:
        data.last_found = newSVpvs("");
        data.longest = &(data.longest_fixed);
        first = scan;
-       if (!r->regstclass) {
+       if (!ri->regstclass) {
            cl_init(pRExC_state, &ch_class);
            data.start_class = &ch_class;
            stclass_flag = SCF_DO_STCLASS_AND;
@@ -4323,7 +4347,7 @@ reStudy:
             && !RExC_seen_zerolen
             && (!(RExC_seen & REG_SEEN_GPOS) || (r->extflags & RXf_ANCH_GPOS)))
            r->extflags |= RXf_CHECK_ALL;
-       scan_commit(pRExC_state, &data,&minlen);
+       scan_commit(pRExC_state, &data,&minlen,0);
        SvREFCNT_dec(data.last_found);
 
         /* Note that code very similar to this but for anchored string 
@@ -4420,22 +4444,22 @@ 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];
+           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);
@@ -4482,7 +4506,7 @@ reStudy:
        
        DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "\nMulti Top Level\n"));
 
-       scan = r->program + 1;
+       scan = ri->program + 1;
        cl_init(pRExC_state, &ch_class);
        data.start_class = &ch_class;
        data.last_closep = &last_close;
@@ -4498,14 +4522,14 @@ 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];
+           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);
@@ -4519,7 +4543,7 @@ reStudy:
        the "real" pattern. */
     DEBUG_OPTIMISE_r({
        PerlIO_printf(Perl_debug_log,"minlen: %"IVdf" r->minlen:%"IVdf"\n",
-           minlen, r->minlen);
+                     (IV)minlen, (IV)r->minlen);
     });
     r->minlenret = minlen;
     if (r->minlen < minlen) 
@@ -4556,15 +4580,15 @@ reStudy:
         PerlIO_printf(Perl_debug_log,"Final program:\n");
         regdump(r);
     });
-    DEBUG_OFFSETS_r(if (r->offsets) {
-        const U32 len = r->offsets[0];
+    DEBUG_OFFSETS_r(if (ri->offsets) {
+        const U32 len = ri->offsets[0];
         U32 i;
         GET_RE_DEBUG_FLAGS_DECL;
-        PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)r->offsets[0]);
+        PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)ri->offsets[0]);
         for (i = 1; i <= len; i++) {
-            if (r->offsets[i*2-1] || r->offsets[i*2])
+            if (ri->offsets[i*2-1] || ri->offsets[i*2])
                 PerlIO_printf(Perl_debug_log, "%"UVuf":%"UVuf"[%"UVuf"] ",
-                (UV)i, (UV)r->offsets[i*2-1], (UV)r->offsets[i*2]);
+                (UV)i, (UV)ri->offsets[i*2-1], (UV)ri->offsets[i*2]);
             }
         PerlIO_printf(Perl_debug_log, "\n");
     });
@@ -4854,7 +4878,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                         if (start_arg) {
                             SV *sv = newSVpvn( start_arg, RExC_parse - start_arg);
                             ARG(ret) = add_data( pRExC_state, 1, "S" );
-                            RExC_rx->data->data[ARG(ret)]=(void*)sv;
+                            RExC_rxi->data->data[ARG(ret)]=(void*)sv;
                             ret->flags = 0;
                         } else {
                             ret->flags = 1; 
@@ -5065,7 +5089,8 @@ 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;
 
@@ -5100,9 +5125,9 @@ 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 */
@@ -5154,7 +5179,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                {
                    char ch = RExC_parse[0] == '<' ? '>' : '\'';
                    char *name_start= RExC_parse++;
-                   I32 num = 0;
+                   U32 num = 0;
                    SV *sv_dat=reg_scan_name(pRExC_state,
                        SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
                    if (RExC_parse == name_start || *RExC_parse != ch)
@@ -5163,7 +5188,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                     RExC_parse++;
                    if (!SIZE_ONLY) {
                         num = add_data( pRExC_state, 1, "S" );
-                        RExC_rx->data->data[num]=(void*)sv_dat;
+                        RExC_rxi->data->data[num]=(void*)sv_dat;
                         SvREFCNT_inc(sv_dat);
                     }
                     ret = reganode(pRExC_state,NGROUPP,num);
@@ -5395,7 +5420,6 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            ender = reg_node(pRExC_state, TAIL);
            break;
        case 1:
-           RExC_cpar++;
            ender = reganode(pRExC_state, CLOSE, parno);
            if (!SIZE_ONLY && RExC_seen & REG_SEEN_RECURSE) {
                DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
@@ -6300,7 +6324,7 @@ tryagain:
                goto defchar;
            } else {
                char* name_start = (RExC_parse += 2);
-               I32 num = 0;
+               U32 num = 0;
                 SV *sv_dat = reg_scan_name(pRExC_state,
                     SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
                 ch= (ch == '<') ? '>' : '\'';
@@ -6319,7 +6343,7 @@ tryagain:
                 if (!SIZE_ONLY) {
                     num = add_data( pRExC_state, 1, "S" );
                     ARG_SET(ret,num);
-                    RExC_rx->data->data[num]=(void*)sv_dat;
+                    RExC_rxi->data->data[num]=(void*)sv_dat;
                     SvREFCNT_inc(sv_dat);
                 }    
                 /* override incorrect value set in reganode MJD */
@@ -6350,7 +6374,7 @@ tryagain:
                    RExC_parse++;
                num = atoi(RExC_parse);
                 if (isrel) {
-                    num = RExC_cpar - num;
+                    num = RExC_npar - num;
                     if (num < 1)
                         vFAIL("Reference to nonexistent or unclosed group");
                 }
@@ -6364,12 +6388,6 @@ tryagain:
                    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,
@@ -6460,6 +6478,7 @@ tryagain:
                    case 'P':
                     case 'N':
                     case 'R':
+                    case 'k':
                        --p;
                        goto loopdone;
                    case 'n':
@@ -7699,7 +7718,7 @@ 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;
@@ -8041,10 +8060,10 @@ 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)]) {
@@ -8090,8 +8109,9 @@ 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) {
@@ -8137,8 +8157,8 @@ Perl_regdump(pTHX_ const regexp *r)
     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->extflags & RXf_ANCH) {
@@ -8154,12 +8174,12 @@ Perl_regdump(pTHX_ const regexp *r)
        PerlIO_putc(Perl_debug_log, ' ');
     }
     if (r->extflags & RXf_GPOS_SEEN)
-       PerlIO_printf(Perl_debug_log, "GPOS:%"UVuf" ", r->gofs);
+       PerlIO_printf(Perl_debug_log, "GPOS:%"UVuf" ", (UV)r->gofs);
     if (r->intflags & PREGf_SKIP)
        PerlIO_printf(Perl_debug_log, "plus ");
     if (r->intflags & PREGf_IMPLICIT)
        PerlIO_printf(Perl_debug_log, "implicit ");
-    PerlIO_printf(Perl_debug_log, "minlen %ld ", (long) r->minlen);
+    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");
@@ -8178,7 +8198,9 @@ 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);
 
@@ -8206,15 +8228,14 @@ 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] :
-            ac->trie;
+        const reg_trie_data * const trie
+           = (reg_trie_data*)progi->data->data[!IS_TRIE_AC(op) ? n : ac->trie];
         
         Perl_sv_catpvf(aTHX_ sv, "-%s",reg_name[o->flags]);
         DEBUG_TRIE_COMPILE_r(
@@ -8267,7 +8288,7 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
     else if (k == VERB) {
         if (!o->flags) 
             Perl_sv_catpvf(aTHX_ sv, ":%"SVf, 
-                (SV*)prog->data->data[ ARG( o ) ]);
+                (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) {
@@ -8446,36 +8467,32 @@ Perl_re_intuit_string(pTHX_ regexp *prog)
 }
 
 /* 
-   pregfree - free a regexp
+   pregfree() 
+   
+   handles refcounting and freeing the perl core regexp structure. When 
+   it is necessary to actually free the structure the first thing it 
+   does is call the 'free' method of the regexp_engine associated to to 
+   the regexp, allowing the handling of the void *pprivate; member 
+   first. (This routine is not overridable by extensions, which is why 
+   the extensions free is called first.)
    
-   See regdupe below if you change anything here. 
+   See regdupe and regdupe_internal if you change anything here. 
 */
-
+#ifndef PERL_IN_XSUB_RE
 void
 Perl_pregfree(pTHX_ struct regexp *r)
 {
     dVAR;
-
     GET_RE_DEBUG_FLAGS_DECL;
 
     if (!r || (--r->refcnt > 0))
        return;
-    DEBUG_COMPILE_r({
-       if (!PL_colorset)
-           reginitcolors();
-       {
-           SV *dsv= sv_newmortal();
-            RE_PV_QUOTED_DECL(s, (r->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);
-        }
-    });
-
+       
+    CALLREGFREE_PVT(r); /* free the private data */
+    
     /* gcov results gave these as non-null 100% of the time, so there's no
        optimisation in checking them before calling Safefree  */
     Safefree(r->precomp);
-    Safefree(r->offsets);             /* 20010421 MJD */
     RX_MATCH_COPY_FREE(r);
 #ifdef PERL_OLD_COPY_ON_WRITE
     if (r->saved_copy)
@@ -8494,24 +8511,64 @@ Perl_pregfree(pTHX_ struct regexp *r)
     }
     if (r->paren_names)
             SvREFCNT_dec(r->paren_names);
-    if (r->data) {
-       int n = r->data->count;
+    
+    Safefree(r->startp);
+    Safefree(r->endp);
+    Safefree(r);
+}
+#endif
+
+/* regfree_internal() 
+
+   Free the private data in a regexp. This is overloadable by 
+   extensions. Perl takes care of the regexp structure in pregfree(), 
+   this covers the *pprivate pointer which technically perldoesnt 
+   know about, however of course we have to handle the 
+   regexp_internal structure when no extension is in use. 
+   
+   Note this is called before freeing anything in the regexp 
+   structure. 
+ */
+void
+Perl_regfree_internal(pTHX_ struct regexp *r)
+{
+    dVAR;
+    RXi_GET_DECL(r,ri);
+    GET_RE_DEBUG_FLAGS_DECL;
+    
+    DEBUG_COMPILE_r({
+       if (!PL_colorset)
+           reginitcolors();
+       {
+           SV *dsv= sv_newmortal();
+            RE_PV_QUOTED_DECL(s, (r->extflags & RXf_UTF8),
+                dsv, r->precomp, r->prelen, 60);
+            PerlIO_printf(Perl_debug_log,"%sFreeing REx:%s %s\n", 
+                PL_colors[4],PL_colors[5],s);
+        }
+    });
+
+    Safefree(ri->offsets);             /* 20010421 MJD */
+    if (ri->data) {
+       int n = ri->data->count;
        PAD* new_comppad = NULL;
        PAD* old_comppad;
        PADOFFSET refcnt;
 
        while (--n >= 0) {
           /* If you add a ->what type here, update the comment in regcomp.h */
-           switch (r->data->what[n]) {
+           switch (ri->data->what[n]) {
            case 's':
            case 'S':
-               SvREFCNT_dec((SV*)r->data->data[n]);
+           case 'u':
+               SvREFCNT_dec((SV*)ri->data->data[n]);
                break;
            case 'f':
-               Safefree(r->data->data[n]);
+               Safefree(ri->data->data[n]);
                break;
            case 'p':
-               new_comppad = (AV*)r->data->data[n];
+               new_comppad = (AV*)ri->data->data[n];
                break;
            case 'o':
                if (new_comppad == NULL)
@@ -8521,10 +8578,10 @@ 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);
@@ -8536,17 +8593,16 @@ Perl_pregfree(pTHX_ struct regexp *r)
                 { /* Aho Corasick add-on structure for a trie node.
                      Used in stclass optimization only */
                     U32 refcount;
-                    reg_ac_data *aho=(reg_ac_data*)r->data->data[n];
+                    reg_ac_data *aho=(reg_ac_data*)ri->data->data[n];
                     OP_REFCNT_LOCK;
                     refcount = --aho->refcount;
                     OP_REFCNT_UNLOCK;
                     if ( !refcount ) {
-                        Safefree(aho->states);
-                        Safefree(aho->fail);
-                        aho->trie=NULL; /* not necessary to free this as it is 
-                                           handled by the 't' case */
-                        Safefree(r->data->data[n]); /* do this last!!!! */
-                        Safefree(r->regstclass);
+                        PerlMemShared_free(aho->states);
+                        PerlMemShared_free(aho->fail);
+                        /* do this last!!!! */
+                        PerlMemShared_free(ri->data->data[n]);
+                        PerlMemShared_free(ri->regstclass);
                     }
                 }
                 break;
@@ -8554,49 +8610,40 @@ Perl_pregfree(pTHX_ struct regexp *r)
                {
                    /* trie structure. */
                    U32 refcount;
-                   reg_trie_data *trie=(reg_trie_data*)r->data->data[n];
+                   reg_trie_data *trie=(reg_trie_data*)ri->data->data[n];
                     OP_REFCNT_LOCK;
                     refcount = --trie->refcount;
                     OP_REFCNT_UNLOCK;
                     if ( !refcount ) {
-                        Safefree(trie->charmap);
-                        if (trie->widecharmap)
-                            SvREFCNT_dec((SV*)trie->widecharmap);
-                        Safefree(trie->states);
-                        Safefree(trie->trans);
+                        PerlMemShared_free(trie->charmap);
+                        PerlMemShared_free(trie->states);
+                        PerlMemShared_free(trie->trans);
                         if (trie->bitmap)
-                            Safefree(trie->bitmap);
+                            PerlMemShared_free(trie->bitmap);
                         if (trie->wordlen)
-                            Safefree(trie->wordlen);
+                            PerlMemShared_free(trie->wordlen);
                         if (trie->jump)
-                            Safefree(trie->jump);
+                            PerlMemShared_free(trie->jump);
                         if (trie->nextword)
-                            Safefree(trie->nextword);
-#ifdef DEBUGGING
-                        if (trie->words)
-                            SvREFCNT_dec((SV*)trie->words);
-                        if (trie->revcharmap)
-                            SvREFCNT_dec((SV*)trie->revcharmap);
-#endif
-                        Safefree(r->data->data[n]); /* do this last!!!! */
+                            PerlMemShared_free(trie->nextword);
+                        /* do this last!!!! */
+                        PerlMemShared_free(ri->data->data[n]);
                    }
                }
                break;
            default:
-               Perl_croak(aTHX_ "panic: regfree data code '%c'", r->data->what[n]);
+               Perl_croak(aTHX_ "panic: regfree data code '%c'", ri->data->what[n]);
            }
        }
-       Safefree(r->data->what);
-       Safefree(r->data);
+       Safefree(ri->data->what);
+       Safefree(ri->data);
     }
-    Safefree(r->startp);
-    Safefree(r->endp);
-    if (r->swap) {
-        Safefree(r->swap->startp);
-        Safefree(r->swap->endp);
-        Safefree(r->swap);
+    if (ri->swap) {
+        Safefree(ri->swap->startp);
+        Safefree(ri->swap->endp);
+        Safefree(ri->swap);
     }
-    Safefree(r);
+    Safefree(ri);
 }
 
 #define sv_dup_inc(s,t)        SvREFCNT_inc(sv_dup(s,t))
@@ -8611,15 +8658,21 @@ Perl_pregfree(pTHX_ struct regexp *r)
    given regexp structure. It is a no-op when not under USE_ITHREADS. 
    (Originally this *was* re_dup() for change history see sv.c)
    
-   See pregfree() above if you change anything here. 
+   After all of the core data stored in struct regexp is duplicated
+   the regexp_engine.dupe method is used to copy any private data
+   stored in the *pprivate pointer. This allows extensions to handle
+   any duplication it needs to do.
+
+   See pregfree() and regfree_internal() if you change anything here. 
 */
 #if defined(USE_ITHREADS)
+#ifndef PERL_IN_XSUB_RE
 regexp *
-Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
+Perl_re_dup(pTHX_ const regexp *r, CLONE_PARAMS *param)
 {
     dVAR;
-    REGEXP *ret;
-    int i, len, npar;
+    regexp *ret;
+    int i, npar;
     struct reg_substr_datum *s;
 
     if (!r)
@@ -8628,24 +8681,13 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
     if ((ret = (REGEXP *)ptr_table_fetch(PL_ptr_table, r)))
        return ret;
 
-    len = r->offsets[0];
+    
     npar = r->nparens+1;
-
-    Newxc(ret, sizeof(regexp) + (len+1)*sizeof(regnode), char, regexp);
-    Copy(r->program, ret->program, len+1, regnode);
-
+    Newxz(ret, 1, regexp);
     Newx(ret->startp, npar, I32);
     Copy(r->startp, ret->startp, npar, I32);
     Newx(ret->endp, npar, I32);
-    Copy(r->startp, ret->startp, npar, I32);
-    if(r->swap) {
-        Newx(ret->swap, 1, regexp_paren_ofs);
-        /* no need to copy these */
-        Newx(ret->swap->startp, npar, I32);
-        Newx(ret->swap->endp, npar, I32);
-    } else {
-        ret->swap = NULL;
-    }
+    Copy(r->endp, ret->endp, npar, I32);
 
     Newx(ret->substrs, 1, struct reg_substr_data);
     for (s = ret->substrs->data, i = 0; i < 3; i++, s++) {
@@ -8655,11 +8697,83 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
        s->substr     = sv_dup_inc(r->substrs->data[i].substr, param);
        s->utf8_substr = sv_dup_inc(r->substrs->data[i].utf8_substr, param);
     }
+    
 
-    ret->regstclass = NULL;
-    if (r->data) {
+    ret->precomp        = SAVEPVN(r->precomp, r->prelen);
+    ret->refcnt         = r->refcnt;
+    ret->minlen         = r->minlen;
+    ret->minlenret      = r->minlenret;
+    ret->prelen         = r->prelen;
+    ret->nparens        = r->nparens;
+    ret->lastparen      = r->lastparen;
+    ret->lastcloseparen = r->lastcloseparen;
+    ret->intflags       = r->intflags;
+    ret->extflags       = r->extflags;
+
+    ret->sublen         = r->sublen;
+
+    ret->engine         = r->engine;
+    
+    ret->paren_names    = hv_dup_inc(r->paren_names, param);
+
+    if (RX_MATCH_COPIED(ret))
+       ret->subbeg  = SAVEPVN(r->subbeg, r->sublen);
+    else
+       ret->subbeg = NULL;
+#ifdef PERL_OLD_COPY_ON_WRITE
+    ret->saved_copy = NULL;
+#endif
+    
+    ret->pprivate = r->pprivate;
+    RXi_SET(ret,CALLREGDUPE_PVT(ret,param));
+    
+    ptr_table_store(PL_ptr_table, r, ret);
+    return ret;
+}
+#endif /* PERL_IN_XSUB_RE */
+
+/*
+   regdupe_internal()
+   
+   This is the internal complement to regdupe() which is used to copy
+   the structure pointed to by the *pprivate pointer in the regexp.
+   This is the core version of the extension overridable cloning hook.
+   The regexp structure being duplicated will be copied by perl prior
+   to this and will be provided as the regexp *r argument, however 
+   with the /old/ structures pprivate pointer value. Thus this routine
+   may override any copying normally done by perl.
+   
+   It returns a pointer to the new regexp_internal structure.
+*/
+
+void *
+Perl_regdupe_internal(pTHX_ const regexp *r, CLONE_PARAMS *param)
+{
+    dVAR;
+    regexp_internal *reti;
+    int len, npar;
+    RXi_GET_DECL(r,ri);
+    
+    npar = r->nparens+1;
+    len = ri->offsets[0];
+    
+    Newxc(reti, sizeof(regexp_internal) + (len+1)*sizeof(regnode), char, regexp_internal);
+    Copy(ri->program, reti->program, len+1, regnode);
+    
+    if(ri->swap) {
+        Newx(reti->swap, 1, regexp_paren_ofs);
+        /* no need to copy these */
+        Newx(reti->swap->startp, npar, I32);
+        Newx(reti->swap->endp, npar, I32);
+    } else {
+        reti->swap = NULL;
+    }
+
+
+    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 *),
@@ -8668,93 +8782,62 @@ 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: sSfpontT
+               /* legal options are one of: sSfpontTu
                   see also regcomp.h and pregfree() */
            case 's':
            case 'S':
-               d->data[i] = sv_dup_inc((SV *)r->data->data[i], param);
-               break;
-           case 'p':
-               d->data[i] = av_dup_inc((AV *)r->data->data[i], param);
+           case 'p': /* actually an AV, but the dup function is identical.  */
+           case 'u': /* actually an HV, but the dup function is identical.  */
+               d->data[i] = sv_dup_inc((SV *)ri->data->data[i], param);
                break;
            case 'f':
                /* This is cheating. */
                Newx(d->data[i], 1, struct regnode_charclass_class);
-               StructCopy(r->data->data[i], d->data[i],
+               StructCopy(ri->data->data[i], d->data[i],
                            struct regnode_charclass_class);
-               ret->regstclass = (regnode*)d->data[i];
+               reti->regstclass = (regnode*)d->data[i];
                break;
            case 'o':
                /* Compiled op trees are readonly and in shared memory,
                   and can thus be shared without duplication. */
                OP_REFCNT_LOCK;
-               d->data[i] = (void*)OpREFCNT_inc((OP*)r->data->data[i]);
-               OP_REFCNT_UNLOCK;
-               break;
-           case 'n':
-               d->data[i] = r->data->data[i];
-               break;
-           case 't':
-               d->data[i] = r->data->data[i];
-               OP_REFCNT_LOCK;
-               ((reg_trie_data*)d->data[i])->refcount++;
+               d->data[i] = (void*)OpREFCNT_inc((OP*)ri->data->data[i]);
                OP_REFCNT_UNLOCK;
                break;
            case 'T':
-               d->data[i] = r->data->data[i];
-               OP_REFCNT_LOCK;
-               ((reg_ac_data*)d->data[i])->refcount++;
-               OP_REFCNT_UNLOCK;
                /* Trie stclasses are readonly and can thus be shared
                 * without duplication. We free the stclass in pregfree
                 * when the corresponding reg_ac_data struct is freed.
                 */
-               ret->regstclass= r->regstclass;
+               reti->regstclass= ri->regstclass;
+               /* Fall through */
+           case 't':
+               OP_REFCNT_LOCK;
+               ((reg_trie_data*)ri->data->data[i])->refcount++;
+               OP_REFCNT_UNLOCK;
+               /* Fall through */
+           case 'n':
+               d->data[i] = ri->data->data[i];
                break;
             default:
-               Perl_croak(aTHX_ "panic: re_dup unknown data code '%c'", r->data->what[i]);
+               Perl_croak(aTHX_ "panic: re_dup unknown data code '%c'", ri->data->what[i]);
            }
        }
 
-       ret->data = d;
+       reti->data = d;
     }
     else
-       ret->data = NULL;
-
-    Newx(ret->offsets, 2*len+1, U32);
-    Copy(r->offsets, ret->offsets, 2*len+1, U32);
+       reti->data = NULL;
 
-    ret->precomp        = SAVEPVN(r->precomp, r->prelen);
-    ret->refcnt         = r->refcnt;
-    ret->minlen         = r->minlen;
-    ret->minlenret      = r->minlenret;
-    ret->prelen         = r->prelen;
-    ret->nparens        = r->nparens;
-    ret->lastparen      = r->lastparen;
-    ret->lastcloseparen = r->lastcloseparen;
-    ret->intflags       = r->intflags;
-    ret->extflags       = r->extflags;
-
-    ret->sublen         = r->sublen;
-
-    ret->engine         = r->engine;
+    Newx(reti->offsets, 2*len+1, U32);
+    Copy(ri->offsets, reti->offsets, 2*len+1, U32);
     
-    ret->paren_names    = hv_dup_inc(r->paren_names, param);
-
-    if (RX_MATCH_COPIED(ret))
-       ret->subbeg  = SAVEPVN(r->subbeg, r->sublen);
-    else
-       ret->subbeg = NULL;
-#ifdef PERL_OLD_COPY_ON_WRITE
-    ret->saved_copy = NULL;
-#endif
-
-    ptr_table_store(PL_ptr_table, r, ret);
-    return ret;
+    return (void*)reti;
 }
-#endif    
+
+#endif    /* USE_ITHREADS */
 
 /* 
    reg_stringify() 
@@ -8767,23 +8850,23 @@ Perl_regdupe(pTHX_ const regexp *r, CLONE_PARAMS *param)
    resulting string
    
    If flags is nonnull and the returned string contains UTF8 then 
-   (flags & 1) will be true.
+   (*flags & 1) will be true.
    
    If haseval is nonnull then it is used to return whether the pattern 
    contains evals.
    
    Normally called via macro: 
    
-        CALLREG_STRINGIFY(mg,0,0);
+        CALLREG_STRINGIFY(mg,&len,&utf8);
         
    And internally with
    
-        CALLREG_AS_STR(mg,lp,flags,haseval)        
+        CALLREG_AS_STR(mg,&lp,&flags,&haseval)        
     
    See sv_2pv_flags() in sv.c for an example of internal usage.
     
  */
-
+#ifndef PERL_IN_XSUB_RE
 char *
 Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
     dVAR;
@@ -8851,7 +8934,7 @@ Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
        mg->mg_ptr[mg->mg_len] = 0;
     }
     if (haseval) 
-        *haseval = re->program[0].next_off;
+        *haseval = re->seen_evals;
     if (flags)    
        *flags = ((re->extflags & RXf_UTF8) ? 1 : 0);
     
@@ -8860,8 +8943,6 @@ Perl_reg_stringify(pTHX_ MAGIC *mg, STRLEN *lp, U32 *flags, I32 *haseval ) {
     return mg->mg_ptr;
 }
 
-
-#ifndef PERL_IN_XSUB_RE
 /*
  - regnext - dig the "next" pointer out of a node
  */
@@ -8871,7 +8952,7 @@ 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));
@@ -8992,7 +9073,7 @@ 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
 
@@ -9007,6 +9088,7 @@ 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
@@ -9072,16 +9154,18 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *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] :
-               ac->trie;
+           const reg_trie_data * const trie =
+               (reg_trie_data*)ri->data->data[op<AHOCORASICK ? n : ac->trie];
+#ifdef DEBUGGING
+           AV *const trie_words = (AV *) ri->data->data[n + TRIE_WORDS_OFFSET];
+#endif
            const regnode *nextbranch= NULL;
            I32 word_idx;
             sv_setpvn(sv, "", 0);
            for (word_idx= 0; word_idx < (I32)trie->wordcount; word_idx++) {
-               SV ** const elem_ptr = av_fetch(trie->words,word_idx,0);
+               SV ** const elem_ptr = av_fetch(trie_words,word_idx,0);
                
                 PerlIO_printf(Perl_debug_log, "%*s%s ",
                    (int)(2*(indent+3)), "",
@@ -9095,8 +9179,8 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
                 );
                 if (trie->jump) {
                     U16 dist= trie->jump[word_idx+1];
-                   PerlIO_printf(Perl_debug_log, "(%u)\n",
-                        (dist ? this_trie + dist : next) - start);
+                   PerlIO_printf(Perl_debug_log, "(%"UVuf")\n",
+                                 (UV)((dist ? this_trie + dist : next) - start));
                     if (dist) {
                         if (!nextbranch)
                             nextbranch= this_trie + trie->jump[0];    
@@ -9144,7 +9228,7 @@ S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
     }
     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;
 }