generalize the 'continue on success' mechanism of deferred REs

[perl5.git] / regexec.c

diff --git a/regexec.c b/regexec.c
index de95e31..4d0388d 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -107,7 +107,7 @@
 #define        STATIC  static
 #endif
 
 #define        STATIC  static
 #endif
 

-#define REGINCLASS(p,c)  (ANYOF_FLAGS(p) ? reginclass(p,c,0,0) : ANYOF_BITMAP_TEST(p,*(c)))
+#define REGINCLASS(prog,p,c)  (ANYOF_FLAGS(p) ? reginclass(prog,p,c,0,0) : ANYOF_BITMAP_TEST(p,*(c)))

 
 /*
  * Forwards.
 
 /*
  * Forwards.


@@ -116,28 +116,20 @@
 #define CHR_SVLEN(sv) (do_utf8 ? sv_len_utf8(sv) : SvCUR(sv))
 #define CHR_DIST(a,b) (PL_reg_match_utf8 ? utf8_distance(a,b) : a - b)
 
 #define CHR_SVLEN(sv) (do_utf8 ? sv_len_utf8(sv) : SvCUR(sv))
 #define CHR_DIST(a,b) (PL_reg_match_utf8 ? utf8_distance(a,b) : a - b)
 

-#define reghop_c(pos,off) ((char*)reghop((U8*)pos, off))
-#define reghopmaybe_c(pos,off) ((char*)reghopmaybe((U8*)pos, off))
-#define HOP(pos,off) (PL_reg_match_utf8 ? reghop((U8*)pos, off) : (U8*)(pos + off))
-#define HOPMAYBE(pos,off) (PL_reg_match_utf8 ? reghopmaybe((U8*)pos, off) : (U8*)(pos + off))
-#define HOPc(pos,off) ((char*)HOP(pos,off))
-#define HOPMAYBEc(pos,off) ((char*)HOPMAYBE(pos,off))
-
-#define HOPBACK(pos, off) (            \
-    (PL_reg_match_utf8)                        \
-       ? reghopmaybe((U8*)pos, -off)   \
+#define HOPc(pos,off) ((char *)(PL_reg_match_utf8 \
+           ? reghop3((U8*)pos, off, (U8*)(off >= 0 ? PL_regeol : PL_bostr)) \
+           : (U8*)(pos + off)))
+#define HOPBACKc(pos, off) ((char*)    \
+    ((PL_reg_match_utf8)               \
+       ? reghopmaybe3((U8*)pos, -off, ((U8*)(off < 0 ? PL_regeol : PL_bostr))) \

     : (pos - off >= PL_bostr)          \
        ? (U8*)(pos - off)              \
     : (pos - off >= PL_bostr)          \
        ? (U8*)(pos - off)              \

-    : (U8*)NULL                                \
+    : (U8*)NULL)                       \

 )
 )

-#define HOPBACKc(pos, off) (char*)HOPBACK(pos, off)

 
 

-#define reghop3_c(pos,off,lim) ((char*)reghop3((U8*)pos, off, (U8*)lim))

 #define reghopmaybe3_c(pos,off,lim) ((char*)reghopmaybe3((U8*)pos, off, (U8*)lim))
 #define HOP3(pos,off,lim) (PL_reg_match_utf8 ? reghop3((U8*)pos, off, (U8*)lim) : (U8*)(pos + off))
 #define reghopmaybe3_c(pos,off,lim) ((char*)reghopmaybe3((U8*)pos, off, (U8*)lim))
 #define HOP3(pos,off,lim) (PL_reg_match_utf8 ? reghop3((U8*)pos, off, (U8*)lim) : (U8*)(pos + off))

-#define HOPMAYBE3(pos,off,lim) (PL_reg_match_utf8 ? reghopmaybe3((U8*)pos, off, (U8*)lim) : (U8*)(pos + off))

 #define HOP3c(pos,off,lim) ((char*)HOP3(pos,off,lim))
 #define HOP3c(pos,off,lim) ((char*)HOP3(pos,off,lim))

-#define HOPMAYBE3c(pos,off,lim) ((char*)HOPMAYBE3(pos,off,lim))

 
 #define LOAD_UTF8_CHARCLASS(class,str) STMT_START { \
     if (!CAT2(PL_utf8_,class)) { bool ok; ENTER; save_re_context(); ok=CAT2(is_utf8_,class)((const U8*)str); assert(ok); LEAVE; } } STMT_END
 
 #define LOAD_UTF8_CHARCLASS(class,str) STMT_START { \
     if (!CAT2(PL_utf8_,class)) { bool ok; ENTER; save_re_context(); ok=CAT2(is_utf8_,class)((const U8*)str); assert(ok); LEAVE; } } STMT_END


@@ -178,6 +170,7 @@ static void restore_pos(pTHX_ void *arg);
 STATIC CHECKPOINT
 S_regcppush(pTHX_ I32 parenfloor)
 {
 STATIC CHECKPOINT
 S_regcppush(pTHX_ I32 parenfloor)
 {

+    dVAR;

     const int retval = PL_savestack_ix;
 #define REGCP_PAREN_ELEMS 4
     const int paren_elems_to_push = (PL_regsize - parenfloor) * REGCP_PAREN_ELEMS;
     const int retval = PL_savestack_ix;
 #define REGCP_PAREN_ELEMS 4
     const int paren_elems_to_push = (PL_regsize - parenfloor) * REGCP_PAREN_ELEMS;


@@ -220,10 +213,10 @@ S_regcppush(pTHX_ I32 parenfloor)
                                (IV)(cp), (IV)PL_savestack_ix) : 0); regcpblow(cp)
 
 STATIC char *
                                (IV)(cp), (IV)PL_savestack_ix) : 0); regcpblow(cp)
 
 STATIC char *

-S_regcppop(pTHX)
+S_regcppop(pTHX_ const regexp *rex)

 {
 {

+    dVAR;

     I32 i;
     I32 i;

-    U32 paren = 0;

     char *input;
 
     GET_RE_DEBUG_FLAGS_DECL;
     char *input;
 
     GET_RE_DEBUG_FLAGS_DECL;


@@ -241,7 +234,7 @@ S_regcppop(pTHX)
     for (i -= (REGCP_OTHER_ELEMS - REGCP_FRAME_ELEMS);
         i > 0; i -= REGCP_PAREN_ELEMS) {
        I32 tmps;
     for (i -= (REGCP_OTHER_ELEMS - REGCP_FRAME_ELEMS);
         i > 0; i -= REGCP_PAREN_ELEMS) {
        I32 tmps;

-       paren = (U32)SSPOPINT;
+       U32 paren = (U32)SSPOPINT;

        PL_reg_start_tmp[paren] = (char *) SSPOPPTR;
        PL_regstartp[paren] = SSPOPINT;
        tmps = SSPOPINT;
        PL_reg_start_tmp[paren] = (char *) SSPOPPTR;
        PL_regstartp[paren] = SSPOPINT;
        tmps = SSPOPINT;


@@ -257,10 +250,10 @@ S_regcppop(pTHX)
        );
     }
     DEBUG_EXECUTE_r(
        );
     }
     DEBUG_EXECUTE_r(

-       if ((I32)(*PL_reglastparen + 1) <= PL_regnpar) {
+       if ((I32)(*PL_reglastparen + 1) <= rex->nparens) {

            PerlIO_printf(Perl_debug_log,
                          "     restoring \\%"IVdf"..\\%"IVdf" to undef\n",
            PerlIO_printf(Perl_debug_log,
                          "     restoring \\%"IVdf"..\\%"IVdf" to undef\n",

-                         (IV)(*PL_reglastparen + 1), (IV)PL_regnpar);
+                         (IV)(*PL_reglastparen + 1), (IV)rex->nparens);

        }
     );
 #if 1
        }
     );
 #if 1


@@ -274,38 +267,18 @@ S_regcppop(pTHX)
      * building DynaLoader will fail:
      * "Error: '*' not in typemap in DynaLoader.xs, line 164"
      * --jhi */
      * building DynaLoader will fail:
      * "Error: '*' not in typemap in DynaLoader.xs, line 164"
      * --jhi */

-    for (paren = *PL_reglastparen + 1; (I32)paren <= PL_regnpar; paren++) {
-       if ((I32)paren > PL_regsize)
-           PL_regstartp[paren] = -1;
-       PL_regendp[paren] = -1;
+    for (i = *PL_reglastparen + 1; i <= rex->nparens; i++) {
+       if (i > PL_regsize)
+           PL_regstartp[i] = -1;
+       PL_regendp[i] = -1;

     }
 #endif
     return input;
 }
 
     }
 #endif
     return input;
 }
 

-STATIC char *
-S_regcp_set_to(pTHX_ I32 ss)
-{
-    const I32 tmp = PL_savestack_ix;
-
-    PL_savestack_ix = ss;
-    regcppop();
-    PL_savestack_ix = tmp;
-    return Nullch;
-}
-
-typedef struct re_cc_state
-{
-    I32 ss;
-    regnode *node;
-    struct re_cc_state *prev;
-    CURCUR *cc;
-    regexp *re;
-} re_cc_state;
-

 #define regcpblow(cp) LEAVE_SCOPE(cp)  /* Ignores regcppush()ed data. */
 
 #define regcpblow(cp) LEAVE_SCOPE(cp)  /* Ignores regcppush()ed data. */
 

-#define TRYPAREN(paren, n, input) {                            \
+#define TRYPAREN(paren, n, input, where) {                     \

     if (paren) {                                               \
        if (n) {                                                \
            PL_regstartp[paren] = HOPc(input, -1) - PL_bostr;   \
     if (paren) {                                               \
        if (n) {                                                \
            PL_regstartp[paren] = HOPc(input, -1) - PL_bostr;   \


@@ -314,7 +287,8 @@ typedef struct re_cc_state
        else                                                    \
            PL_regendp[paren] = -1;                             \
     }                                                          \
        else                                                    \
            PL_regendp[paren] = -1;                             \
     }                                                          \

-    if (regmatch(next))                                                \
+    REGMATCH(next, where);                                     \
+    if (result)                                                        \

        sayYES;                                                 \
     if (paren && n)                                            \
        PL_regendp[paren] = -1;                                 \
        sayYES;                                                 \
     if (paren && n)                                            \
        PL_regendp[paren] = -1;                                 \


@@ -341,17 +315,6 @@ Perl_pregexec(pTHX_ register regexp *prog, char *stringarg, register char *stren
                      nosave ? 0 : REXEC_COPY_STR);
 }
 
                      nosave ? 0 : REXEC_COPY_STR);
 }
 

-STATIC void
-S_cache_re(pTHX_ regexp *prog)
-{
-    PL_regprecomp = prog->precomp;             /* Needed for FAIL. */
-#ifdef DEBUGGING
-    PL_regprogram = prog->program;
-#endif
-    PL_regnpar = prog->nparens;
-    PL_regdata = prog->data;
-    PL_reg_re = prog;
-}

 
 /*
  * Need to implement the following flags for reg_anch:
 
 /*
  * Need to implement the following flags for reg_anch:


@@ -403,6 +366,7 @@ char *
 Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                     char *strend, U32 flags, re_scream_pos_data *data)
 {
 Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                     char *strend, U32 flags, re_scream_pos_data *data)
 {

+    dVAR;

     register I32 start_shift = 0;
     /* Should be nonnegative! */
     register I32 end_shift   = 0;
     register I32 start_shift = 0;
     /* Should be nonnegative! */
     register I32 end_shift   = 0;


@@ -412,8 +376,8 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     char *t;
     const int do_utf8 = sv ? SvUTF8(sv) : 0;   /* if no sv we have to assume bytes */
     I32 ml_anch;
     char *t;
     const int do_utf8 = sv ? SvUTF8(sv) : 0;   /* if no sv we have to assume bytes */
     I32 ml_anch;

-    register char *other_last = Nullch;        /* other substr checked before this */
-    char *check_at = Nullch;           /* check substr found at this pos */
+    register char *other_last = NULL;  /* other substr checked before this */
+    char *check_at = NULL;             /* check substr found at this pos */

     const I32 multiline = prog->reganch & PMf_MULTILINE;
 #ifdef DEBUGGING
     const char * const i_strpos = strpos;
     const I32 multiline = prog->reganch & PMf_MULTILINE;
 #ifdef DEBUGGING
     const char * const i_strpos = strpos;


@@ -839,9 +803,9 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
            SvREFCNT_dec(do_utf8 ? prog->check_utf8 : prog->check_substr);
            if (do_utf8 ? prog->check_substr : prog->check_utf8)
                SvREFCNT_dec(do_utf8 ? prog->check_substr : prog->check_utf8);
            SvREFCNT_dec(do_utf8 ? prog->check_utf8 : prog->check_substr);
            if (do_utf8 ? prog->check_substr : prog->check_utf8)
                SvREFCNT_dec(do_utf8 ? prog->check_substr : prog->check_utf8);

-           prog->check_substr = prog->check_utf8 = Nullsv;     /* disable */
-           prog->float_substr = prog->float_utf8 = Nullsv;     /* clear */
-           check = Nullsv;                     /* abort */
+           prog->check_substr = prog->check_utf8 = NULL;       /* disable */
+           prog->float_substr = prog->float_utf8 = NULL;       /* clear */
+           check = NULL;                       /* abort */

            s = strpos;
            /* XXXX This is a remnant of the old implementation.  It
                    looks wasteful, since now INTUIT can use many
            s = strpos;
            /* XXXX This is a remnant of the old implementation.  It
                    looks wasteful, since now INTUIT can use many


@@ -875,8 +839,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                   : strend);
 
        t = s;
                   : strend);
 
        t = s;

-       cache_re(prog);
-        s = find_byclass(prog, prog->regstclass, s, endpos, 1);
+        s = find_byclass(prog, prog->regstclass, s, endpos, NULL);

        if (!s) {
 #ifdef DEBUGGING
            const char *what = NULL;
        if (!s) {
 #ifdef DEBUGGING
            const char *what = NULL;


@@ -964,12 +927,15 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
   fail:
     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch rejected by optimizer%s\n",
                          PL_colors[4], PL_colors[5]));
   fail:
     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch rejected by optimizer%s\n",
                          PL_colors[4], PL_colors[5]));

-    return Nullch;
+    return NULL;

 }
 
 /* We know what class REx starts with.  Try to find this position... */
 }
 
 /* We know what class REx starts with.  Try to find this position... */

+/* if reginfo is NULL, its a dryrun */
+

 STATIC char *
 STATIC char *

-S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32 norun)
+S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s, const char
+*strend, const regmatch_info *reginfo)

 {
        dVAR;
        const I32 doevery = (prog->reganch & ROPT_SKIP) == 0;
 {
        dVAR;
        const I32 doevery = (prog->reganch & ROPT_SKIP) == 0;


@@ -990,9 +956,9 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                 while (s + (uskip = UTF8SKIP(s)) <= strend) {
                      if ((ANYOF_FLAGS(c) & ANYOF_UNICODE) ||
                          !UTF8_IS_INVARIANT((U8)s[0]) ?
                 while (s + (uskip = UTF8SKIP(s)) <= strend) {
                      if ((ANYOF_FLAGS(c) & ANYOF_UNICODE) ||
                          !UTF8_IS_INVARIANT((U8)s[0]) ?

-                         reginclass(c, (U8*)s, 0, do_utf8) :
-                         REGINCLASS(c, (U8*)s)) {
-                          if (tmp && (norun || regtry(prog, s)))
+                         reginclass(prog, c, (U8*)s, 0, do_utf8) :
+                         REGINCLASS(prog, c, (U8*)s)) {
+                          if (tmp && (!reginfo || regtry(reginfo, s)))

                                goto got_it;
                           else
                                tmp = doevery;
                                goto got_it;
                           else
                                tmp = doevery;


@@ -1006,12 +972,12 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                 while (s < strend) {
                      STRLEN skip = 1;
 
                 while (s < strend) {
                      STRLEN skip = 1;
 

-                     if (REGINCLASS(c, (U8*)s) ||
+                     if (REGINCLASS(prog, c, (U8*)s) ||

                          (ANYOF_FOLD_SHARP_S(c, s, strend) &&
                           /* The assignment of 2 is intentional:
                            * for the folded sharp s, the skip is 2. */
                           (skip = SHARP_S_SKIP))) {
                          (ANYOF_FOLD_SHARP_S(c, s, strend) &&
                           /* The assignment of 2 is intentional:
                            * for the folded sharp s, the skip is 2. */
                           (skip = SHARP_S_SKIP))) {

-                          if (tmp && (norun || regtry(prog, s)))
+                          if (tmp && (!reginfo || regtry(reginfo, s)))

                                goto got_it;
                           else
                                tmp = doevery;
                                goto got_it;
                           else
                                tmp = doevery;


@@ -1024,7 +990,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            break;
        case CANY:
            while (s < strend) {
            break;
        case CANY:
            while (s < strend) {

-               if (tmp && (norun || regtry(prog, s)))
+               if (tmp && (!reginfo || regtry(reginfo, s)))

                    goto got_it;
                else
                    tmp = doevery;
                    goto got_it;
                else
                    tmp = doevery;


@@ -1040,7 +1006,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                U8 *sm = (U8 *) m;
                U8 tmpbuf1[UTF8_MAXBYTES_CASE+1];
                U8 tmpbuf2[UTF8_MAXBYTES_CASE+1];
                U8 *sm = (U8 *) m;
                U8 tmpbuf1[UTF8_MAXBYTES_CASE+1];
                U8 tmpbuf2[UTF8_MAXBYTES_CASE+1];

-               const U32 uniflags = ckWARN(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY;
+               const U32 uniflags = UTF8_ALLOW_DEFAULT;

 
                to_utf8_lower((U8*)m, tmpbuf1, &ulen1);
                to_utf8_upper((U8*)m, tmpbuf2, &ulen2);
 
                to_utf8_lower((U8*)m, tmpbuf1, &ulen1);
                to_utf8_upper((U8*)m, tmpbuf2, &ulen2);


@@ -1069,7 +1035,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
          do_exactf:
            e = HOP3c(strend, -((I32)lnc), s);
 
          do_exactf:
            e = HOP3c(strend, -((I32)lnc), s);
 

-           if (norun && e < s)
+           if (!reginfo && e < s)

                e = s;                  /* Due to minlen logic of intuit() */
 
            /* The idea in the EXACTF* cases is to first find the
                e = s;                  /* Due to minlen logic of intuit() */
 
            /* The idea in the EXACTF* cases is to first find the


@@ -1087,7 +1053,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                UV c, f;
                U8 tmpbuf [UTF8_MAXBYTES+1];
                STRLEN len, foldlen;
                UV c, f;
                U8 tmpbuf [UTF8_MAXBYTES+1];
                STRLEN len, foldlen;

-               const U32 uniflags = ckWARN(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY;
+               const U32 uniflags = UTF8_ALLOW_DEFAULT;

                if (c1 == c2) {
                    /* Upper and lower of 1st char are equal -
                     * probably not a "letter". */
                if (c1 == c2) {
                    /* Upper and lower of 1st char are equal -
                     * probably not a "letter". */


@@ -1098,7 +1064,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                             && (ln == len ||
                                 ibcmp_utf8(s, (char **)0, 0,  do_utf8,
                                            m, (char **)0, ln, (bool)UTF))
                             && (ln == len ||
                                 ibcmp_utf8(s, (char **)0, 0,  do_utf8,
                                            m, (char **)0, ln, (bool)UTF))

-                            && (norun || regtry(prog, s)) )
+                            && (!reginfo || regtry(reginfo, s)) )

                            goto got_it;
                        else {
                             U8 foldbuf[UTF8_MAXBYTES_CASE+1];
                            goto got_it;
                        else {
                             U8 foldbuf[UTF8_MAXBYTES_CASE+1];


@@ -1111,7 +1077,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                                                  (char **)0, foldlen, do_utf8,
                                                  m,
                                                  (char **)0, ln, (bool)UTF))
                                                  (char **)0, foldlen, do_utf8,
                                                  m,
                                                  (char **)0, ln, (bool)UTF))

-                                 && (norun || regtry(prog, s)) )
+                                 && (!reginfo || regtry(reginfo, s)) )

                                  goto got_it;
                        }
                        s += len;
                                  goto got_it;
                        }
                        s += len;


@@ -1137,7 +1103,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                             && (ln == len ||
                                 ibcmp_utf8(s, (char **)0, 0,  do_utf8,
                                            m, (char **)0, ln, (bool)UTF))
                             && (ln == len ||
                                 ibcmp_utf8(s, (char **)0, 0,  do_utf8,
                                            m, (char **)0, ln, (bool)UTF))

-                            && (norun || regtry(prog, s)) )
+                            && (!reginfo || regtry(reginfo, s)) )

                            goto got_it;
                        else {
                             U8 foldbuf[UTF8_MAXBYTES_CASE+1];
                            goto got_it;
                        else {
                             U8 foldbuf[UTF8_MAXBYTES_CASE+1];


@@ -1150,7 +1116,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                                                  (char **)0, foldlen, do_utf8,
                                                  m,
                                                  (char **)0, ln, (bool)UTF))
                                                  (char **)0, foldlen, do_utf8,
                                                  m,
                                                  (char **)0, ln, (bool)UTF))

-                                 && (norun || regtry(prog, s)) )
+                                 && (!reginfo || regtry(reginfo, s)) )

                                  goto got_it;
                        }
                        s += len;
                                  goto got_it;
                        }
                        s += len;


@@ -1164,7 +1130,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                             && (ln == 1 || !(OP(c) == EXACTF
                                              ? ibcmp(s, m, ln)
                                              : ibcmp_locale(s, m, ln)))
                             && (ln == 1 || !(OP(c) == EXACTF
                                              ? ibcmp(s, m, ln)
                                              : ibcmp_locale(s, m, ln)))

-                            && (norun || regtry(prog, s)) )
+                            && (!reginfo || regtry(reginfo, s)) )

                            goto got_it;
                        s++;
                    }
                            goto got_it;
                        s++;
                    }


@@ -1174,7 +1140,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                             && (ln == 1 || !(OP(c) == EXACTF
                                              ? ibcmp(s, m, ln)
                                              : ibcmp_locale(s, m, ln)))
                             && (ln == 1 || !(OP(c) == EXACTF
                                              ? ibcmp(s, m, ln)
                                              : ibcmp_locale(s, m, ln)))

-                            && (norun || regtry(prog, s)) )
+                            && (!reginfo || regtry(reginfo, s)) )

                            goto got_it;
                        s++;
                    }
                            goto got_it;
                        s++;
                    }


@@ -1188,9 +1154,8 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                if (s == PL_bostr)
                    tmp = '\n';
                else {
                if (s == PL_bostr)
                    tmp = '\n';
                else {

-                   U8 *r = reghop3((U8*)s, -1, (U8*)PL_bostr);
-               
-                   tmp = utf8n_to_uvchr(r, UTF8SKIP(r), 0, 0);
+                   U8 * const r = reghop3((U8*)s, -1, (U8*)PL_bostr);
+                   tmp = utf8n_to_uvchr(r, UTF8SKIP(r), 0, UTF8_ALLOW_DEFAULT);

                }
                tmp = ((OP(c) == BOUND ?
                        isALNUM_uni(tmp) : isALNUM_LC_uvchr(UNI_TO_NATIVE(tmp))) != 0);
                }
                tmp = ((OP(c) == BOUND ?
                        isALNUM_uni(tmp) : isALNUM_LC_uvchr(UNI_TO_NATIVE(tmp))) != 0);


@@ -1201,7 +1166,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                                 isALNUM_LC_utf8((U8*)s)))
                    {
                        tmp = !tmp;
                                 isALNUM_LC_utf8((U8*)s)))
                    {
                        tmp = !tmp;

-                       if ((norun || regtry(prog, s)))
+                       if ((!reginfo || regtry(reginfo, s)))

                            goto got_it;
                    }
                    s += uskip;
                            goto got_it;
                    }
                    s += uskip;


@@ -1214,13 +1179,13 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                    if (tmp ==
                        !(OP(c) == BOUND ? isALNUM(*s) : isALNUM_LC(*s))) {
                        tmp = !tmp;
                    if (tmp ==
                        !(OP(c) == BOUND ? isALNUM(*s) : isALNUM_LC(*s))) {
                        tmp = !tmp;

-                       if ((norun || regtry(prog, s)))
+                       if ((!reginfo || regtry(reginfo, s)))

                            goto got_it;
                    }
                    s++;
                }
            }
                            goto got_it;
                    }
                    s++;
                }
            }

-           if ((!prog->minlen && tmp) && (norun || regtry(prog, s)))
+           if ((!prog->minlen && tmp) && (!reginfo || regtry(reginfo, s)))

                goto got_it;
            break;
        case NBOUNDL:
                goto got_it;
            break;
        case NBOUNDL:


@@ -1231,9 +1196,8 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                if (s == PL_bostr)
                    tmp = '\n';
                else {
                if (s == PL_bostr)
                    tmp = '\n';
                else {

-                   U8 *r = reghop3((U8*)s, -1, (U8*)PL_bostr);
-               
-                   tmp = utf8n_to_uvchr(r, UTF8SKIP(r), 0, 0);
+                   U8 * const r = reghop3((U8*)s, -1, (U8*)PL_bostr);
+                   tmp = utf8n_to_uvchr(r, UTF8SKIP(r), 0, UTF8_ALLOW_DEFAULT);

                }
                tmp = ((OP(c) == NBOUND ?
                        isALNUM_uni(tmp) : isALNUM_LC_uvchr(UNI_TO_NATIVE(tmp))) != 0);
                }
                tmp = ((OP(c) == NBOUND ?
                        isALNUM_uni(tmp) : isALNUM_LC_uvchr(UNI_TO_NATIVE(tmp))) != 0);


@@ -1243,7 +1207,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                                 swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8) :
                                 isALNUM_LC_utf8((U8*)s)))
                        tmp = !tmp;
                                 swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8) :
                                 isALNUM_LC_utf8((U8*)s)))
                        tmp = !tmp;

-                   else if ((norun || regtry(prog, s)))
+                   else if ((!reginfo || regtry(reginfo, s)))

                        goto got_it;
                    s += uskip;
                }
                        goto got_it;
                    s += uskip;
                }


@@ -1256,12 +1220,12 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                    if (tmp ==
                        !(OP(c) == NBOUND ? isALNUM(*s) : isALNUM_LC(*s)))
                        tmp = !tmp;
                    if (tmp ==
                        !(OP(c) == NBOUND ? isALNUM(*s) : isALNUM_LC(*s)))
                        tmp = !tmp;

-                   else if ((norun || regtry(prog, s)))
+                   else if ((!reginfo || regtry(reginfo, s)))

                        goto got_it;
                    s++;
                }
            }
                        goto got_it;
                    s++;
                }
            }

-           if ((!prog->minlen && !tmp) && (norun || regtry(prog, s)))
+           if ((!prog->minlen && !tmp) && (!reginfo || regtry(reginfo, s)))

                goto got_it;
            break;
        case ALNUM:
                goto got_it;
            break;
        case ALNUM:


@@ -1269,7 +1233,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_ALNUM();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8)) {
                LOAD_UTF8_CHARCLASS_ALNUM();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1282,7 +1246,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isALNUM(*s)) {
            else {
                while (s < strend) {
                    if (isALNUM(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1298,7 +1262,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (isALNUM_LC_utf8((U8*)s)) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (isALNUM_LC_utf8((U8*)s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1311,7 +1275,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isALNUM_LC(*s)) {
            else {
                while (s < strend) {
                    if (isALNUM_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1327,7 +1291,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_ALNUM();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8)) {
                LOAD_UTF8_CHARCLASS_ALNUM();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!swash_fetch(PL_utf8_alnum, (U8*)s, do_utf8)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1340,7 +1304,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isALNUM(*s)) {
            else {
                while (s < strend) {
                    if (!isALNUM(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1356,7 +1320,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!isALNUM_LC_utf8((U8*)s)) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!isALNUM_LC_utf8((U8*)s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1369,7 +1333,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isALNUM_LC(*s)) {
            else {
                while (s < strend) {
                    if (!isALNUM_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1385,7 +1349,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_SPACE();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s, do_utf8)) {
                LOAD_UTF8_CHARCLASS_SPACE();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s, do_utf8)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1398,7 +1362,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isSPACE(*s)) {
            else {
                while (s < strend) {
                    if (isSPACE(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1414,7 +1378,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (*s == ' ' || isSPACE_LC_utf8((U8*)s)) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (*s == ' ' || isSPACE_LC_utf8((U8*)s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1427,7 +1391,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isSPACE_LC(*s)) {
            else {
                while (s < strend) {
                    if (isSPACE_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1443,7 +1407,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_SPACE();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!(*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s, do_utf8))) {
                LOAD_UTF8_CHARCLASS_SPACE();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!(*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s, do_utf8))) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1456,7 +1420,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isSPACE(*s)) {
            else {
                while (s < strend) {
                    if (!isSPACE(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1472,7 +1436,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!(*s == ' ' || isSPACE_LC_utf8((U8*)s))) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!(*s == ' ' || isSPACE_LC_utf8((U8*)s))) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1485,7 +1449,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isSPACE_LC(*s)) {
            else {
                while (s < strend) {
                    if (!isSPACE_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1501,7 +1465,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_DIGIT();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (swash_fetch(PL_utf8_digit,(U8*)s, do_utf8)) {
                LOAD_UTF8_CHARCLASS_DIGIT();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (swash_fetch(PL_utf8_digit,(U8*)s, do_utf8)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1514,7 +1478,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isDIGIT(*s)) {
            else {
                while (s < strend) {
                    if (isDIGIT(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1530,7 +1494,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (isDIGIT_LC_utf8((U8*)s)) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (isDIGIT_LC_utf8((U8*)s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1543,7 +1507,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (isDIGIT_LC(*s)) {
            else {
                while (s < strend) {
                    if (isDIGIT_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1559,7 +1523,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
                LOAD_UTF8_CHARCLASS_DIGIT();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!swash_fetch(PL_utf8_digit,(U8*)s, do_utf8)) {
                LOAD_UTF8_CHARCLASS_DIGIT();
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!swash_fetch(PL_utf8_digit,(U8*)s, do_utf8)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1572,7 +1536,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isDIGIT(*s)) {
            else {
                while (s < strend) {
                    if (!isDIGIT(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1588,7 +1552,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!isDIGIT_LC_utf8((U8*)s)) {
            if (do_utf8) {
                while (s + (uskip = UTF8SKIP(s)) <= strend) {
                    if (!isDIGIT_LC_utf8((U8*)s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1601,7 +1565,7 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, const char *strend, I32
            else {
                while (s < strend) {
                    if (!isDIGIT_LC(*s)) {
            else {
                while (s < strend) {
                    if (!isDIGIT_LC(*s)) {

-                       if (tmp && (norun || regtry(prog, s)))
+                       if (tmp && (!reginfo || regtry(reginfo, s)))

                            goto got_it;
                        else
                            tmp = doevery;
                            goto got_it;
                        else
                            tmp = doevery;


@@ -1633,6 +1597,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
 /* data: May be used for some additional optimizations. */
 /* nosave: For optimizations. */
 {
 /* data: May be used for some additional optimizations. */
 /* nosave: For optimizations. */
 {

+    dVAR;

     register char *s;
     register regnode *c;
     register char *startpos = stringarg;
     register char *s;
     register regnode *c;
     register char *startpos = stringarg;


@@ -1640,26 +1605,19 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
     I32 dontbother = 0;        /* how many characters not to try at end */
     I32 end_shift = 0;                 /* Same for the end. */         /* CC */
     I32 scream_pos = -1;               /* Internal iterator of scream. */
     I32 dontbother = 0;        /* how many characters not to try at end */
     I32 end_shift = 0;                 /* Same for the end. */         /* CC */
     I32 scream_pos = -1;               /* Internal iterator of scream. */

-    char *scream_olds;
+    char *scream_olds = NULL;

     SV* oreplsv = GvSV(PL_replgv);
     const bool do_utf8 = DO_UTF8(sv);
     SV* oreplsv = GvSV(PL_replgv);
     const bool do_utf8 = DO_UTF8(sv);

-    const I32 multiline = prog->reganch & PMf_MULTILINE;
+    I32 multiline;

 #ifdef DEBUGGING
 #ifdef DEBUGGING

-    SV *dsv0 = PERL_DEBUG_PAD_ZERO(0);
-    SV *dsv1 = PERL_DEBUG_PAD_ZERO(1);
+    SV* dsv0;
+    SV* dsv1;

 #endif
 #endif

+    regmatch_info reginfo;  /* create some info to pass to regtry etc */

 
     GET_RE_DEBUG_FLAGS_DECL;
 
     PERL_UNUSED_ARG(data);
 
     GET_RE_DEBUG_FLAGS_DECL;
 
     PERL_UNUSED_ARG(data);

-    RX_MATCH_UTF8_set(prog,do_utf8);
-
-    PL_regcc = 0;
-
-    cache_re(prog);
-#ifdef DEBUGGING
-    PL_regnarrate = DEBUG_r_TEST;
-#endif

 
     /* Be paranoid... */
     if (prog == NULL || startpos == NULL) {
 
     /* Be paranoid... */
     if (prog == NULL || startpos == NULL) {


@@ -1667,6 +1625,16 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        return 0;
     }
 
        return 0;
     }
 

+    multiline = prog->reganch & PMf_MULTILINE;
+    reginfo.prog = prog;
+
+#ifdef DEBUGGING
+    dsv0 = PERL_DEBUG_PAD_ZERO(0);
+    dsv1 = PERL_DEBUG_PAD_ZERO(1);
+#endif
+
+    RX_MATCH_UTF8_set(prog, do_utf8);
+

     minlen = prog->minlen;
     if (strend - startpos < minlen) {
         DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
     minlen = prog->minlen;
     if (strend - startpos < minlen) {
         DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,


@@ -1687,43 +1655,40 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        PL_reg_flags |= RF_utf8;
 
     /* Mark beginning of line for ^ and lookbehind. */
        PL_reg_flags |= RF_utf8;
 
     /* Mark beginning of line for ^ and lookbehind. */

-    PL_regbol = startpos;
+    reginfo.bol = startpos; /* XXX not used ??? */

     PL_bostr  = strbeg;
     PL_bostr  = strbeg;

-    PL_reg_sv = sv;
+    reginfo.sv = sv;

 
     /* Mark end of line for $ (and such) */
     PL_regeol = strend;
 
     /* see how far we have to get to not match where we matched before */
 
     /* Mark end of line for $ (and such) */
     PL_regeol = strend;
 
     /* see how far we have to get to not match where we matched before */

-    PL_regtill = startpos+minend;
-
-    /* We start without call_cc context.  */
-    PL_reg_call_cc = 0;
+    reginfo.till = startpos+minend;

 
     /* If there is a "must appear" string, look for it. */
     s = startpos;
 
 
     /* If there is a "must appear" string, look for it. */
     s = startpos;
 

-    if (prog->reganch & ROPT_GPOS_SEEN) { /* Need to have PL_reg_ganch */
+    if (prog->reganch & ROPT_GPOS_SEEN) { /* Need to set reginfo->ganch */

        MAGIC *mg;
 
        if (flags & REXEC_IGNOREPOS)    /* Means: check only at start */
        MAGIC *mg;
 
        if (flags & REXEC_IGNOREPOS)    /* Means: check only at start */

-           PL_reg_ganch = startpos;
+           reginfo.ganch = startpos;

        else if (sv && SvTYPE(sv) >= SVt_PVMG
                  && SvMAGIC(sv)
                  && (mg = mg_find(sv, PERL_MAGIC_regex_global))
                  && mg->mg_len >= 0) {
        else if (sv && SvTYPE(sv) >= SVt_PVMG
                  && SvMAGIC(sv)
                  && (mg = mg_find(sv, PERL_MAGIC_regex_global))
                  && mg->mg_len >= 0) {

-           PL_reg_ganch = strbeg + mg->mg_len; /* Defined pos() */
+           reginfo.ganch = strbeg + mg->mg_len;        /* Defined pos() */

            if (prog->reganch & ROPT_ANCH_GPOS) {
            if (prog->reganch & ROPT_ANCH_GPOS) {

-               if (s > PL_reg_ganch)
+               if (s > reginfo.ganch)

                    goto phooey;
                    goto phooey;

-               s = PL_reg_ganch;
+               s = reginfo.ganch;

            }
        }
        else                            /* pos() not defined */
            }
        }
        else                            /* pos() not defined */

-           PL_reg_ganch = strbeg;
+           reginfo.ganch = strbeg;

     }
 
     }
 

-    if (!(flags & REXEC_CHECKED) && (prog->check_substr != Nullsv || prog->check_utf8 != Nullsv)) {
+    if (!(flags & REXEC_CHECKED) && (prog->check_substr != NULL || prog->check_utf8 != NULL)) {

        re_scream_pos_data d;
 
        d.scream_olds = &scream_olds;
        re_scream_pos_data d;
 
        d.scream_olds = &scream_olds;


@@ -1762,7 +1727,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
     /* Simplest case:  anchored match need be tried only once. */
     /*  [unless only anchor is BOL and multiline is set] */
     if (prog->reganch & (ROPT_ANCH & ~ROPT_ANCH_GPOS)) {
     /* Simplest case:  anchored match need be tried only once. */
     /*  [unless only anchor is BOL and multiline is set] */
     if (prog->reganch & (ROPT_ANCH & ~ROPT_ANCH_GPOS)) {

-       if (s == startpos && regtry(prog, startpos))
+       if (s == startpos && regtry(&reginfo, startpos))

            goto got_it;
        else if (multiline || (prog->reganch & ROPT_IMPLICIT)
                 || (prog->reganch & ROPT_ANCH_MBOL)) /* XXXX SBOL? */
            goto got_it;
        else if (multiline || (prog->reganch & ROPT_IMPLICIT)
                 || (prog->reganch & ROPT_ANCH_MBOL)) /* XXXX SBOL? */


@@ -1777,7 +1742,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                if (s == startpos)
                    goto after_try;
                while (1) {
                if (s == startpos)
                    goto after_try;
                while (1) {

-                   if (regtry(prog, s))
+                   if (regtry(&reginfo, s))

                        goto got_it;
                  after_try:
                    if (s >= end)
                        goto got_it;
                  after_try:
                    if (s >= end)


@@ -1795,7 +1760,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                    s--;
                while (s < end) {
                    if (*s++ == '\n') { /* don't need PL_utf8skip here */
                    s--;
                while (s < end) {
                    if (*s++ == '\n') { /* don't need PL_utf8skip here */

-                       if (regtry(prog, s))
+                       if (regtry(&reginfo, s))

                            goto got_it;
                    }
                }               
                            goto got_it;
                    }
                }               


@@ -1803,7 +1768,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        }
        goto phooey;
     } else if (prog->reganch & ROPT_ANCH_GPOS) {
        }
        goto phooey;
     } else if (prog->reganch & ROPT_ANCH_GPOS) {

-       if (regtry(prog, PL_reg_ganch))
+       if (regtry(&reginfo, reginfo.ganch))

            goto got_it;
        goto phooey;
     }
            goto got_it;
        goto phooey;
     }


@@ -1824,7 +1789,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
            while (s < strend) {
                if (*s == ch) {
                    DEBUG_EXECUTE_r( did_match = 1 );
            while (s < strend) {
                if (*s == ch) {
                    DEBUG_EXECUTE_r( did_match = 1 );

-                   if (regtry(prog, s)) goto got_it;
+                   if (regtry(&reginfo, s)) goto got_it;

                    s += UTF8SKIP(s);
                    while (s < strend && *s == ch)
                        s += UTF8SKIP(s);
                    s += UTF8SKIP(s);
                    while (s < strend && *s == ch)
                        s += UTF8SKIP(s);


@@ -1836,7 +1801,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
            while (s < strend) {
                if (*s == ch) {
                    DEBUG_EXECUTE_r( did_match = 1 );
            while (s < strend) {
                if (*s == ch) {
                    DEBUG_EXECUTE_r( did_match = 1 );

-                   if (regtry(prog, s)) goto got_it;
+                   if (regtry(&reginfo, s)) goto got_it;

                    s++;
                    while (s < strend && *s == ch)
                        s++;
                    s++;
                    while (s < strend && *s == ch)
                        s++;


@@ -1849,9 +1814,9 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                                   "Did not find anchored character...\n")
                );
     }
                                   "Did not find anchored character...\n")
                );
     }

-    else if (prog->anchored_substr != Nullsv
-             || prog->anchored_utf8 != Nullsv
-             || ((prog->float_substr != Nullsv || prog->float_utf8 != Nullsv)
+    else if (prog->anchored_substr != NULL
+             || prog->anchored_utf8 != NULL
+             || ((prog->float_substr != NULL || prog->float_utf8 != NULL)

                  && prog->float_max_offset < strend - s)) {
        SV *must;
        I32 back_max;
                  && prog->float_max_offset < strend - s)) {
        SV *must;
        I32 back_max;


@@ -1907,21 +1872,21 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                s = HOPc(s, -back_max);
            }
            else {
                s = HOPc(s, -back_max);
            }
            else {

-               char *t = (last1 >= PL_bostr) ? HOPc(last1, 1) : last1 + 1;
+               char * const t = (last1 >= PL_bostr) ? HOPc(last1, 1) : last1 + 1;

 
                last1 = HOPc(s, -back_min);
 
                last1 = HOPc(s, -back_min);

-               s = t;          
+               s = t;

            }
            if (do_utf8) {
                while (s <= last1) {
            }
            if (do_utf8) {
                while (s <= last1) {

-                   if (regtry(prog, s))
+                   if (regtry(&reginfo, s))

                        goto got_it;
                    s += UTF8SKIP(s);
                }
            }
            else {
                while (s <= last1) {
                        goto got_it;
                    s += UTF8SKIP(s);
                }
            }
            else {
                while (s <= last1) {

-                   if (regtry(prog, s))
+                   if (regtry(&reginfo, s))

                        goto got_it;
                    s++;
                }
                        goto got_it;
                    s++;
                }


@@ -1953,7 +1918,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
            int len0;
            int len1;
 
            int len0;
            int len1;
 

-           regprop(prop, c);
+           regprop(prog, prop, c);

            s0 = UTF ?
              pv_uni_display(dsv0, (U8*)SvPVX_const(prop), SvCUR(prop), 60,
                             UNI_DISPLAY_REGEX) :
            s0 = UTF ?
              pv_uni_display(dsv0, (U8*)SvPVX_const(prop), SvCUR(prop), 60,
                             UNI_DISPLAY_REGEX) :


@@ -1967,13 +1932,13 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                          len0, len0, s0,
                          len1, len1, s1);
        });
                          len0, len0, s0,
                          len1, len1, s1);
        });

-        if (find_byclass(prog, c, s, strend, 0))
+        if (find_byclass(prog, c, s, strend, &reginfo))

            goto got_it;
        DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass...\n"));
     }
     else {
        dontbother = 0;
            goto got_it;
        DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass...\n"));
     }
     else {
        dontbother = 0;

-       if (prog->float_substr != Nullsv || prog->float_utf8 != Nullsv) {
+       if (prog->float_substr != NULL || prog->float_utf8 != NULL) {

            /* Trim the end. */
            char *last;
            SV* float_real;
            /* Trim the end. */
            char *last;
            SV* float_real;


@@ -2000,7 +1965,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                        last = strend - len + 1;
                    else if (!multiline)
                        last = memEQ(strend - len, little, len)
                        last = strend - len + 1;
                    else if (!multiline)
                        last = memEQ(strend - len, little, len)

-                           ? strend - len : Nullch;
+                           ? strend - len : NULL;

                    else
                        goto find_last;
                } else {
                    else
                        goto find_last;
                } else {


@@ -2025,7 +1990,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        /* We don't know much -- general case. */
        if (do_utf8) {
            for (;;) {
        /* We don't know much -- general case. */
        if (do_utf8) {
            for (;;) {

-               if (regtry(prog, s))
+               if (regtry(&reginfo, s))

                    goto got_it;
                if (s >= strend)
                    break;
                    goto got_it;
                if (s >= strend)
                    break;


@@ -2034,7 +1999,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        }
        else {
            do {
        }
        else {
            do {

-               if (regtry(prog, s))
+               if (regtry(&reginfo, s))

                    goto got_it;
            } while (s++ < strend);
        }
                    goto got_it;
            } while (s++ < strend);
        }


@@ -2052,7 +2017,7 @@ got_it:
            sv_setsv(oreplsv, GvSV(PL_replgv));/* So that when GvSV(replgv) is
                                                  restored, the value remains
                                                  the same. */
            sv_setsv(oreplsv, GvSV(PL_replgv));/* So that when GvSV(replgv) is
                                                  restored, the value remains
                                                  the same. */

-       restore_pos(aTHX_ 0);
+       restore_pos(aTHX_ prog);

     }
 
     /* make sure $`, $&, $', and $digit will work later */
     }
 
     /* make sure $`, $&, $', and $digit will work later */


@@ -2092,7 +2057,7 @@ phooey:
     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
                          PL_colors[4], PL_colors[5]));
     if (PL_reg_eval_set)
     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
                          PL_colors[4], PL_colors[5]));
     if (PL_reg_eval_set)

-       restore_pos(aTHX_ 0);
+       restore_pos(aTHX_ prog);

     return 0;
 }
 
     return 0;
 }
 


@@ -2100,12 +2065,13 @@ phooey:
  - regtry - try match at specific point
  */
 STATIC I32                     /* 0 failure, 1 success */
  - regtry - try match at specific point
  */
 STATIC I32                     /* 0 failure, 1 success */

-S_regtry(pTHX_ regexp *prog, char *startpos)
+S_regtry(pTHX_ const regmatch_info *reginfo, char *startpos)

 {
 {

-    register I32 i;
+    dVAR;

     register I32 *sp;
     register I32 *ep;
     CHECKPOINT lastcp;
     register I32 *sp;
     register I32 *ep;
     CHECKPOINT lastcp;

+    regexp *prog = reginfo->prog;

     GET_RE_DEBUG_FLAGS_DECL;
 
 #ifdef DEBUGGING
     GET_RE_DEBUG_FLAGS_DECL;
 
 #ifdef DEBUGGING


@@ -2127,24 +2093,27 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
        /* SAVEI8(cxstack[cxstack_ix].blk_gimme);
           cxstack[cxstack_ix].blk_gimme = G_SCALAR; */
 
        /* SAVEI8(cxstack[cxstack_ix].blk_gimme);
           cxstack[cxstack_ix].blk_gimme = G_SCALAR; */
 

-       if (PL_reg_sv) {
+       if (reginfo->sv) {

            /* Make $_ available to executed code. */
            /* Make $_ available to executed code. */

-           if (PL_reg_sv != DEFSV) {
+           if (reginfo->sv != DEFSV) {

                SAVE_DEFSV;
                SAVE_DEFSV;

-               DEFSV = PL_reg_sv;
+               DEFSV = reginfo->sv;

            }
        
            }
        

-           if (!(SvTYPE(PL_reg_sv) >= SVt_PVMG && SvMAGIC(PL_reg_sv)
-                 && (mg = mg_find(PL_reg_sv, PERL_MAGIC_regex_global)))) {
+           if (!(SvTYPE(reginfo->sv) >= SVt_PVMG && SvMAGIC(reginfo->sv)
+                 && (mg = mg_find(reginfo->sv, PERL_MAGIC_regex_global)))) {

                /* prepare for quick setting of pos */
                /* prepare for quick setting of pos */

-               sv_magic(PL_reg_sv, (SV*)0,
-                       PERL_MAGIC_regex_global, Nullch, 0);
-               mg = mg_find(PL_reg_sv, PERL_MAGIC_regex_global);
+#ifdef PERL_OLD_COPY_ON_WRITE
+               if (SvIsCOW(sv))
+                   sv_force_normal_flags(sv, 0);
+#endif
+               mg = sv_magicext(reginfo->sv, (SV*)0, PERL_MAGIC_regex_global,
+                                &PL_vtbl_mglob, NULL, 0);

                mg->mg_len = -1;
            }
            PL_reg_magic    = mg;
            PL_reg_oldpos   = mg->mg_len;
                mg->mg_len = -1;
            }
            PL_reg_magic    = mg;
            PL_reg_oldpos   = mg->mg_len;

-           SAVEDESTRUCTOR_X(restore_pos, 0);
+           SAVEDESTRUCTOR_X(restore_pos, prog);

         }
         if (!PL_reg_curpm) {
            Newxz(PL_reg_curpm, 1, PMOP);
         }
         if (!PL_reg_curpm) {
            Newxz(PL_reg_curpm, 1, PMOP);


@@ -2174,7 +2143,7 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
            RX_MATCH_COPIED_off(prog);
        }
        else
            RX_MATCH_COPIED_off(prog);
        }
        else

-           PL_reg_oldsaved = Nullch;
+           PL_reg_oldsaved = NULL;

        prog->subbeg = PL_bostr;
        prog->sublen = PL_regeol - PL_bostr; /* strend may have been modified */
     }
        prog->subbeg = PL_bostr;
        prog->sublen = PL_regeol - PL_bostr; /* strend may have been modified */
     }


@@ -2214,6 +2183,7 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
     sp = prog->startp;
     ep = prog->endp;
     if (prog->nparens) {
     sp = prog->startp;
     ep = prog->endp;
     if (prog->nparens) {

+       register I32 i;

        for (i = prog->nparens; i > (I32)*PL_reglastparen; i--) {
            *++sp = -1;
            *++ep = -1;
        for (i = prog->nparens; i > (I32)*PL_reglastparen; i--) {
            *++sp = -1;
            *++ep = -1;


@@ -2221,7 +2191,7 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
     }
 #endif
     REGCP_SET(lastcp);
     }
 #endif
     REGCP_SET(lastcp);

-    if (regmatch(prog->program + 1)) {
+    if (regmatch(reginfo, prog->program + 1)) {

        prog->endp[0] = PL_reginput - PL_bostr;
        return 1;
     }
        prog->endp[0] = PL_reginput - PL_bostr;
        return 1;
     }


@@ -2248,6 +2218,7 @@ typedef struct {
     regnode *next;
     char *locinput;
     I32 nextchr;
     regnode *next;
     char *locinput;
     I32 nextchr;

+    int minmod;

 #ifdef DEBUGGING
     int regindent;
 #endif
 #ifdef DEBUGGING
     int regindent;
 #endif


@@ -2272,7 +2243,7 @@ typedef union re_unwind_t {
 #define POSCACHE_SEEN 1                /* we know what we're caching */
 #define POSCACHE_START 2       /* the real cache: this bit maps to pos 0 */
 #define CACHEsayYES STMT_START { \
 #define POSCACHE_SEEN 1                /* we know what we're caching */
 #define POSCACHE_START 2       /* the real cache: this bit maps to pos 0 */
 #define CACHEsayYES STMT_START { \

-    if (cache_offset | cache_bit) { \
+    if (st->u.whilem.cache_offset | st->u.whilem.cache_bit) { \

        if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
            PL_reg_poscache[0] |= (1<<POSCACHE_SUCCESS) || (1<<POSCACHE_SEEN); \
         else if (!(PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
        if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
            PL_reg_poscache[0] |= (1<<POSCACHE_SUCCESS) || (1<<POSCACHE_SEEN); \
         else if (!(PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \


@@ -2282,13 +2253,13 @@ typedef union re_unwind_t {
                    "%*s  (remove success from failure cache)\n", \
                    REPORT_CODE_OFF+PL_regindent*2, "") \
            ); \
                    "%*s  (remove success from failure cache)\n", \
                    REPORT_CODE_OFF+PL_regindent*2, "") \
            ); \

-           PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+           PL_reg_poscache[st->u.whilem.cache_offset] &= ~(1<<st->u.whilem.cache_bit); \

        } \
     } \
     sayYES; \
 } STMT_END
 #define CACHEsayNO STMT_START { \
        } \
     } \
     sayYES; \
 } STMT_END
 #define CACHEsayNO STMT_START { \

-    if (cache_offset | cache_bit) { \
+    if (st->u.whilem.cache_offset | st->u.whilem.cache_bit) { \

        if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
            PL_reg_poscache[0] |= (1<<POSCACHE_SEEN); \
         else if ((PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
        if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) \
            PL_reg_poscache[0] |= (1<<POSCACHE_SEEN); \
         else if ((PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \


@@ -2298,7 +2269,7 @@ typedef union re_unwind_t {
                    "%*s  (remove failure from success cache)\n", \
                    REPORT_CODE_OFF+PL_regindent*2, "") \
            ); \
                    "%*s  (remove failure from success cache)\n", \
                    REPORT_CODE_OFF+PL_regindent*2, "") \
            ); \

-           PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+           PL_reg_poscache[st->u.whilem.cache_offset] &= ~(1<<st->u.whilem.cache_bit); \

        } \
     } \
     sayNO; \
        } \
     } \
     sayNO; \


@@ -2316,57 +2287,71 @@ typedef union re_unwind_t {
 /* Make sure there is a test for this +1 options in re_tests */
 #define TRIE_INITAL_ACCEPT_BUFFLEN 4;
 
 /* Make sure there is a test for this +1 options in re_tests */
 #define TRIE_INITAL_ACCEPT_BUFFLEN 4;
 

-#define TRIE_CHECK_STATE_IS_ACCEPTING STMT_START {                       \
-    if ( trie->states[ state ].wordnum ) {                               \
-       if ( !accepted ) {                                               \
-           ENTER;                                                       \
-           SAVETMPS;                                                    \
-           bufflen = TRIE_INITAL_ACCEPT_BUFFLEN ;                       \
-           sv_accept_buff=NEWSV( 1234,                                  \
-             bufflen * sizeof(reg_trie_accepted) - 1 );                 \
-           SvCUR_set( sv_accept_buff, sizeof(reg_trie_accepted) );      \
-           SvPOK_on( sv_accept_buff );                                  \
-           sv_2mortal( sv_accept_buff );                                \
-           accept_buff = (reg_trie_accepted*)SvPV_nolen( sv_accept_buff );\
-       } else {                                                         \
-           if ( accepted >= bufflen ) {                                 \
-               bufflen *= 2;                                            \
-               accept_buff =(reg_trie_accepted*)SvGROW( sv_accept_buff, \
-                   bufflen * sizeof(reg_trie_accepted) );               \
-           }                                                            \
-           SvCUR_set( sv_accept_buff,SvCUR( sv_accept_buff )            \
-               + sizeof( reg_trie_accepted ) );                         \
-       }                                                                \
-       accept_buff[ accepted ].wordnum = trie->states[ state ].wordnum; \
-       accept_buff[ accepted ].endpos = uc;                             \
-       ++accepted;                                                      \
-    } } STMT_END
-
-#define TRIE_HANDLE_CHAR STMT_START {                                   \
-        if ( uvc < 256 ) {                                              \
-            charid = trie->charmap[ uvc ];                              \
-        } else {                                                        \
-            charid = 0;                                                 \
-            if( trie->widecharmap ) {                                   \
-            SV** svpp = (SV**)NULL;                                     \
-            svpp = hv_fetch( trie->widecharmap, (char*)&uvc,            \
-                         sizeof( UV ), 0 );                            \
-            if ( svpp ) {                                               \
-               charid = (U16)SvIV( *svpp );                            \
-                }                                                       \
-            }                                                           \
-        }                                                               \
-        if ( charid &&                                                  \
-             ( base + charid > trie->uniquecharcount ) &&               \
-             ( base + charid - 1 - trie->uniquecharcount < trie->lasttrans) && \
-             trie->trans[ base + charid - 1 - trie->uniquecharcount ].check == state ) \
-        {                                                               \
-            state = trie->trans[ base + charid - 1 - trie->uniquecharcount ].next;     \
-        } else {                                                        \
-            state = 0;                                                  \
-        }                                                               \
-        uc += len;                                                      \
-    } STMT_END
+#define SLAB_FIRST(s) (&(s)->states[0])
+#define SLAB_LAST(s)  (&(s)->states[PERL_REGMATCH_SLAB_SLOTS-1])
+
+/* grab a new slab and return the first slot in it */
+
+STATIC regmatch_state *
+S_push_slab(pTHX)
+{
+    regmatch_slab *s = PL_regmatch_slab->next;
+    if (!s) {
+       Newx(s, 1, regmatch_slab);
+       s->prev = PL_regmatch_slab;
+       s->next = NULL;
+       PL_regmatch_slab->next = s;
+    }
+    PL_regmatch_slab = s;
+    return SLAB_FIRST(s);
+}
+
+/* simulate a recursive call to regmatch */
+
+#define REGMATCH(ns, where) \
+    st->scan = scan; \
+    scan = (ns); \
+    st->resume_state = resume_##where; \
+    goto start_recurse; \
+    resume_point_##where:
+
+
+/* push a new regex state. Set newst to point to it */
+
+#define PUSH_STATE(newst, resume) \
+    depth++;   \
+    DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "PUSH STATE(%d)\n", depth)); \
+    st->scan = scan;   \
+    st->next = next;   \
+    st->n = n; \
+    st->locinput = locinput;   \
+    st->resume_state = resume; \
+    newst = st+1;   \
+    if (newst >  SLAB_LAST(PL_regmatch_slab)) \
+       newst = S_push_slab(aTHX);  \
+    PL_regmatch_state = newst; \
+    newst->cc = 0;  \
+    newst->minmod = 0; \
+    newst->sw = 0;  \
+    newst->logical = 0;        \
+    newst->unwind = 0; \
+    locinput = PL_reginput; \
+    nextchr = UCHARAT(locinput);    
+
+#define POP_STATE \
+    DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "POP STATE(%d)\n", depth)); \
+    depth--; \
+    st--; \
+    if (st < SLAB_FIRST(PL_regmatch_slab)) { \
+       PL_regmatch_slab = PL_regmatch_slab->prev; \
+       st = SLAB_LAST(PL_regmatch_slab); \
+    } \
+    PL_regmatch_state = st; \
+    scan       = st->scan; \
+    next       = st->next; \
+    n          = st->n; \
+    locinput   = st->locinput; \
+    nextchr = UCHARAT(locinput);

 
 /*
  - regmatch - main matching routine
 
 /*
  - regmatch - main matching routine


@@ -2381,57 +2366,165 @@ typedef union re_unwind_t {
 /* [lwall] I've hoisted the register declarations to the outer block in order to
  * maybe save a little bit of pushing and popping on the stack.  It also takes
  * advantage of machines that use a register save mask on subroutine entry.
 /* [lwall] I've hoisted the register declarations to the outer block in order to
  * maybe save a little bit of pushing and popping on the stack.  It also takes
  * advantage of machines that use a register save mask on subroutine entry.

+ *
+ * This function used to be heavily recursive, but since this had the
+ * effect of blowing the CPU stack on complex regexes, it has been
+ * restructured to be iterative, and to save state onto the heap rather
+ * than the stack. Essentially whereever regmatch() used to be called, it
+ * pushes the current state, notes where to return, then jumps back into
+ * the main loop.
+ *
+ * Originally the structure of this function used to look something like
+
+    S_regmatch() {
+       int a = 1, b = 2;
+       ...
+       while (scan != NULL) {
+           a++; // do stuff with a and b
+           ...
+           switch (OP(scan)) {
+               case FOO: {
+                   int local = 3;
+                   ...
+                   if (regmatch(...))  // recurse
+                       goto yes;
+               }
+               ...
+           }
+       }
+       yes:
+       return 1;
+    }
+
+ * Now it looks something like this:
+
+    typedef struct {
+       int a, b, local;
+       int resume_state;
+    } regmatch_state;
+
+    S_regmatch() {
+       regmatch_state *st = new();
+       int depth=0;
+       st->a++; // do stuff with a and b
+       ...
+       while (scan != NULL) {
+           ...
+           switch (OP(scan)) {
+               case FOO: {
+                   st->local = 3;
+                   ...
+                   st->scan = scan;
+                   scan = ...;
+                   st->resume_state = resume_FOO;
+                   goto start_recurse; // recurse
+
+                   resume_point_FOO:
+                   if (result)
+                       goto yes;
+               }
+               ...
+           }
+         start_recurse:
+           st = new(); push a new state
+           st->a = 1; st->b = 2;
+           depth++;
+       }
+      yes:
+       result = 1;
+       if (depth--) {
+           st = pop();
+           switch (resume_state) {
+           case resume_FOO:
+               goto resume_point_FOO;
+           ...
+           }
+       }
+       return result
+    }
+           
+ * WARNING: this means that any line in this function that contains a
+ * REGMATCH() or TRYPAREN() is actually simulating a recursive call to
+ * regmatch() using gotos instead. Thus the values of any local variables
+ * not saved in the regmatch_state structure will have been lost when
+ * execution resumes on the next line .
+ *
+ * States (ie the st pointer) are allocated in slabs of about 4K in size.
+ * PL_regmatch_state always points to the currently active state, and
+ * PL_regmatch_slab points to the slab currently containing PL_regmatch_state.
+ * The first time regmatch is called, the first slab is allocated, and is
+ * never freed until interpreter desctruction. When the slab is full,
+ * a new one is allocated chained to the end. At exit from regmatch, slabs
+ * allocated since entry are freed.

  */
  */

+ 
+

 STATIC I32                     /* 0 failure, 1 success */
 STATIC I32                     /* 0 failure, 1 success */

-S_regmatch(pTHX_ regnode *prog)
+S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)

 {
     dVAR;
 {
     dVAR;

-    register regnode *scan;    /* Current node. */
-    regnode *next;             /* Next node. */
-    regnode *inner;            /* Next node in internal branch. */
-    register I32 nextchr;      /* renamed nextchr - nextchar colides with
-                                  function of same name */
-    register I32 n;            /* no or next */
-    register I32 ln = 0;       /* len or last */
-    register char *s = Nullch; /* operand or save */
-    register char *locinput = PL_reginput;
-    register I32 c1 = 0, c2 = 0, paren;        /* case fold search, parenth */
-    int minmod = 0, sw = 0, logical = 0;
-    I32 unwind = 0;
-
-    /* used by the trie code */
-    SV                 *sv_accept_buff = NULL; /* accepting states we have traversed */
-    reg_trie_accepted  *accept_buff = NULL;  /* "" */
-    reg_trie_data      *trie;                /* what trie are we using right now */
-    U32 accepted = 0;                        /* how many accepting states we have seen*/
-
-#if 0
-    I32 firstcp = PL_savestack_ix;
-#endif

     register const bool do_utf8 = PL_reg_match_utf8;
     register const bool do_utf8 = PL_reg_match_utf8;

-#ifdef DEBUGGING
-    SV *dsv0 = PERL_DEBUG_PAD_ZERO(0);
-    SV *dsv1 = PERL_DEBUG_PAD_ZERO(1);
-    SV *dsv2 = PERL_DEBUG_PAD_ZERO(2);
+    const U32 uniflags = UTF8_ALLOW_DEFAULT;

 
 

-    SV *re_debug_flags = NULL;
-#endif
-    U32 uniflags = ckWARN(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY;
+    regexp *rex = reginfo->prog;

 
 

-    GET_RE_DEBUG_FLAGS;
+    regmatch_slab  *orig_slab;
+    regmatch_state *orig_state;
+
+    /* the current state. This is a cached copy of PL_regmatch_state */
+    register regmatch_state *st;

 
 

+    /* cache heavy used fields of st in registers */
+    register regnode *scan;
+    register regnode *next;
+    register I32 n = 0;        /* initialize to shut up compiler warning */
+    register char *locinput = PL_reginput;
+
+    /* these variables are NOT saved during a recusive RFEGMATCH: */
+    register I32 nextchr;   /* is always set to UCHARAT(locinput) */
+    bool result;           /* return value of S_regmatch */
+    regnode *inner;        /* Next node in internal branch. */
+    int depth = 0;         /* depth of recursion */
+    regmatch_state *newst;  /* when pushing a state, this is the new one */
+    regmatch_state *yes_state = NULL; /* state to pop to on success of
+                                                           subpattern */
+    

 #ifdef DEBUGGING
 #ifdef DEBUGGING

+    SV *re_debug_flags = NULL;
+    GET_RE_DEBUG_FLAGS;

     PL_regindent++;
 #endif
 
     PL_regindent++;
 #endif
 

+    /* on first ever call to regmatch, allocate first slab */
+    if (!PL_regmatch_slab) {
+       Newx(PL_regmatch_slab, 1, regmatch_slab);
+       PL_regmatch_slab->prev = NULL;
+       PL_regmatch_slab->next = NULL;
+       PL_regmatch_state = SLAB_FIRST(PL_regmatch_slab);
+    }

 
 

+    /* remember current high-water mark for exit */
+    /* XXX this should be done with SAVE* instead */
+    orig_slab  = PL_regmatch_slab;
+    orig_state = PL_regmatch_state;
+
+    /* grab next free state slot */
+    st = ++PL_regmatch_state;
+    if (st >  SLAB_LAST(PL_regmatch_slab))
+       st = PL_regmatch_state = S_push_slab(aTHX);
+
+    st->minmod = 0;
+    st->sw = 0;
+    st->logical = 0;
+    st->unwind = 0;
+    st->cc = NULL;

     /* Note that nextchr is a byte even in UTF */
     nextchr = UCHARAT(locinput);
     scan = prog;
     while (scan != NULL) {
 
         DEBUG_EXECUTE_r( {
     /* Note that nextchr is a byte even in UTF */
     nextchr = UCHARAT(locinput);
     scan = prog;
     while (scan != NULL) {
 
         DEBUG_EXECUTE_r( {

-           SV *prop = sv_newmortal();
+           SV * const prop = sv_newmortal();

            const int docolor = *PL_colors[0];
            const int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
            int l = (PL_regeol - locinput) > taill ? taill : (PL_regeol - locinput);
            const int docolor = *PL_colors[0];
            const int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
            int l = (PL_regeol - locinput) > taill ? taill : (PL_regeol - locinput);


@@ -2457,21 +2550,22 @@ S_regmatch(pTHX_ regnode *prog)
                pref0_len = 0;
            if (pref0_len > pref_len)
                pref0_len = pref_len;
                pref0_len = 0;
            if (pref0_len > pref_len)
                pref0_len = pref_len;

-           regprop(prop, scan);
+           regprop(rex, prop, scan);

            {
              const char * const s0 =
                do_utf8 && OP(scan) != CANY ?
            {
              const char * const s0 =
                do_utf8 && OP(scan) != CANY ?

-               pv_uni_display(dsv0, (U8*)(locinput - pref_len),
+               pv_uni_display(PERL_DEBUG_PAD(0), (U8*)(locinput - pref_len),

                               pref0_len, 60, UNI_DISPLAY_REGEX) :
                locinput - pref_len;
              const int len0 = do_utf8 ? strlen(s0) : pref0_len;
              const char * const s1 = do_utf8 && OP(scan) != CANY ?
                               pref0_len, 60, UNI_DISPLAY_REGEX) :
                locinput - pref_len;
              const int len0 = do_utf8 ? strlen(s0) : pref0_len;
              const char * const s1 = do_utf8 && OP(scan) != CANY ?

-               pv_uni_display(dsv1, (U8*)(locinput - pref_len + pref0_len),
+               pv_uni_display(PERL_DEBUG_PAD(1),
+                              (U8*)(locinput - pref_len + pref0_len),

                               pref_len - pref0_len, 60, UNI_DISPLAY_REGEX) :
                locinput - pref_len + pref0_len;
              const int len1 = do_utf8 ? strlen(s1) : pref_len - pref0_len;
              const char * const s2 = do_utf8 && OP(scan) != CANY ?
                               pref_len - pref0_len, 60, UNI_DISPLAY_REGEX) :
                locinput - pref_len + pref0_len;
              const int len1 = do_utf8 ? strlen(s1) : pref_len - pref0_len;
              const char * const s2 = do_utf8 && OP(scan) != CANY ?

-               pv_uni_display(dsv2, (U8*)locinput,
+               pv_uni_display(PERL_DEBUG_PAD(2), (U8*)locinput,

                               PL_regeol - locinput, 60, UNI_DISPLAY_REGEX) :
                locinput;
              const int len2 = do_utf8 ? strlen(s2) : l;
                               PL_regeol - locinput, 60, UNI_DISPLAY_REGEX) :
                locinput;
              const int len2 = do_utf8 ? strlen(s2) : l;


@@ -2490,7 +2584,7 @@ S_regmatch(pTHX_ regnode *prog)
                            PL_colors[1],
                            15 - l - pref_len + 1,
                            "",
                            PL_colors[1],
                            15 - l - pref_len + 1,
                            "",

-                           (IV)(scan - PL_regprogram), PL_regindent*2, "",
+                           (IV)(scan - rex->program), PL_regindent*2, "",

                            SvPVX_const(prop));
            }
        });
                            SvPVX_const(prop));
            }
        });


@@ -2503,7 +2597,7 @@ S_regmatch(pTHX_ regnode *prog)
        case BOL:
            if (locinput == PL_bostr)
            {
        case BOL:
            if (locinput == PL_bostr)
            {

-               /* regtill = regbol; */
+               /* reginfo->till = reginfo->bol; */

                break;
            }
            sayNO;
                break;
            }
            sayNO;


@@ -2519,7 +2613,7 @@ S_regmatch(pTHX_ regnode *prog)
                break;
            sayNO;
        case GPOS:
                break;
            sayNO;
        case GPOS:

-           if (locinput == PL_reg_ganch)
+           if (locinput == reginfo->ganch)

                break;
            sayNO;
        case EOL:
                break;
            sayNO;
        case EOL:


@@ -2575,12 +2669,9 @@ S_regmatch(pTHX_ regnode *prog)
           traverse the TRIE keeping track of all accepting states
           we transition through until we get to a failing node.
 
           traverse the TRIE keeping track of all accepting states
           we transition through until we get to a failing node.
 

-          we use two slightly different pieces of code to handle
-          the traversal depending on whether its case sensitive or
-          not. we reuse the accept code however. (this should probably
-          be turned into a macro.)

 
        */
 
        */

+       case TRIE:

        case TRIEF:
        case TRIEFL:
            {
        case TRIEF:
        case TRIEFL:
            {


@@ -2593,13 +2684,48 @@ S_regmatch(pTHX_ regnode *prog)
                STRLEN foldlen = 0;
                U8 *uscan = (U8*)NULL;
                STRLEN bufflen=0;
                STRLEN foldlen = 0;
                U8 *uscan = (U8*)NULL;
                STRLEN bufflen=0;

-               accepted = 0;
-
-               trie = (reg_trie_data*)PL_regdata->data[ ARG( scan ) ];
+               SV *sv_accept_buff = NULL;
+               const enum { trie_plain, trie_utf8, trie_uft8_fold }
+                   trie_type = do_utf8 ?
+                         (OP(scan) == TRIE ? trie_utf8 : trie_uft8_fold)
+                       : trie_plain;
+
+               /* what trie are we using right now */
+               reg_trie_data *trie
+                   = (reg_trie_data*)rex->data->data[ ARG( scan ) ];
+               st->u.trie.accepted = 0; /* how many accepting states we have seen */
+               result = 0;

 
                while ( state && uc <= (U8*)PL_regeol ) {
 
 
                while ( state && uc <= (U8*)PL_regeol ) {
 

-                   TRIE_CHECK_STATE_IS_ACCEPTING;
+                   if (trie->states[ state ].wordnum) {
+                       if (!st->u.trie.accepted ) {
+                           ENTER;
+                           SAVETMPS;
+                           bufflen = TRIE_INITAL_ACCEPT_BUFFLEN;
+                           sv_accept_buff=newSV(bufflen *
+                                           sizeof(reg_trie_accepted) - 1);
+                           SvCUR_set(sv_accept_buff,
+                                               sizeof(reg_trie_accepted));
+                           SvPOK_on(sv_accept_buff);
+                           sv_2mortal(sv_accept_buff);
+                           st->u.trie.accept_buff =
+                               (reg_trie_accepted*)SvPV_nolen(sv_accept_buff );
+                       }
+                       else {
+                           if (st->u.trie.accepted >= bufflen) {
+                               bufflen *= 2;
+                               st->u.trie.accept_buff =(reg_trie_accepted*)
+                                   SvGROW(sv_accept_buff,
+                                       bufflen * sizeof(reg_trie_accepted));
+                           }
+                           SvCUR_set(sv_accept_buff,SvCUR(sv_accept_buff)
+                               + sizeof(reg_trie_accepted));
+                       }
+                       st->u.trie.accept_buff[st->u.trie.accepted].wordnum = trie->states[state].wordnum;
+                       st->u.trie.accept_buff[st->u.trie.accepted].endpos = uc;
+                       ++st->u.trie.accepted;
+                   }

 
                    base = trie->states[ state ].trans.base;
 
 
                    base = trie->states[ state ].trans.base;
 


@@ -2607,12 +2733,12 @@ S_regmatch(pTHX_ regnode *prog)
                                PerlIO_printf( Perl_debug_log,
                                    "%*s  %sState: %4"UVxf", Base: %4"UVxf", Accepted: %4"UVxf" ",
                                    REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4],
                                PerlIO_printf( Perl_debug_log,
                                    "%*s  %sState: %4"UVxf", Base: %4"UVxf", Accepted: %4"UVxf" ",
                                    REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4],

-                                   (UV)state, (UV)base, (UV)accepted );
+                                   (UV)state, (UV)base, (UV)st->u.trie.accepted );

                    );
 
                    if ( base ) {
                    );
 
                    if ( base ) {

-
-                       if ( do_utf8 ) {
+                       switch (trie_type) {
+                       case trie_uft8_fold:

                            if ( foldlen>0 ) {
                                uvc = utf8n_to_uvuni( uscan, UTF8_MAXLEN, &len, uniflags );
                                foldlen -= len;
                            if ( foldlen>0 ) {
                                uvc = utf8n_to_uvuni( uscan, UTF8_MAXLEN, &len, uniflags );
                                foldlen -= len;


@@ -2625,14 +2751,47 @@ S_regmatch(pTHX_ regnode *prog)
                                foldlen -= UNISKIP( uvc );
                                uscan = foldbuf + UNISKIP( uvc );
                            }
                                foldlen -= UNISKIP( uvc );
                                uscan = foldbuf + UNISKIP( uvc );
                            }

-                       } else {
+                           break;
+                       case trie_utf8:
+                           uvc = utf8n_to_uvuni( (U8*)uc, UTF8_MAXLEN,
+                                                           &len, uniflags );
+                           break;
+                       case trie_plain:

                            uvc = (UV)*uc;
                            len = 1;
                        }
 
                            uvc = (UV)*uc;
                            len = 1;
                        }
 

-                       TRIE_HANDLE_CHAR;
+                       if (uvc < 256) {
+                           charid = trie->charmap[ uvc ];
+                       }
+                       else {
+                           charid = 0;
+                           if (trie->widecharmap) {
+                               SV** svpp = (SV**)NULL;
+                               svpp = hv_fetch(trie->widecharmap,
+                                           (char*)&uvc, sizeof(UV), 0);
+                               if (svpp)
+                                   charid = (U16)SvIV(*svpp);
+                           }
+                       }
+
+                       if (charid &&
+                            (base + charid > trie->uniquecharcount )
+                            && (base + charid - 1 - trie->uniquecharcount
+                                   < trie->lasttrans)
+                            && trie->trans[base + charid - 1 -
+                                   trie->uniquecharcount].check == state)
+                       {
+                           state = trie->trans[base + charid - 1 -
+                               trie->uniquecharcount ].next;
+                       }
+                       else {
+                           state = 0;
+                       }
+                       uc += len;

 
 

-                   } else {
+                   }
+                   else {

                        state = 0;
                    }
                    DEBUG_TRIE_EXECUTE_r(
                        state = 0;
                    }
                    DEBUG_TRIE_EXECUTE_r(


@@ -2641,65 +2800,8 @@ S_regmatch(pTHX_ regnode *prog)
                            charid, uvc, (UV)state, PL_colors[5] );
                    );
                }
                            charid, uvc, (UV)state, PL_colors[5] );
                    );
                }

-               if ( !accepted ) {
-                  sayNO;
-               } else {
-                   goto TrieAccept;
-               }
-           }
-           /* unreached codepoint: we jump into the middle of the next case
-              from previous if blocks */
-       case TRIE:
-           {
-               U8 *uc = (U8*)locinput;
-               U32 state = 1;
-               U16 charid = 0;
-               U32 base = 0;
-               UV uvc = 0;
-               STRLEN len = 0;
-               STRLEN bufflen = 0;
-               accepted = 0;
-
-               trie = (reg_trie_data*)PL_regdata->data[ ARG( scan ) ];
-
-               while ( state && uc <= (U8*)PL_regeol ) {
-
-                   TRIE_CHECK_STATE_IS_ACCEPTING;
-
-                   base = trie->states[ state ].trans.base;
-
-                   DEBUG_TRIE_EXECUTE_r(
-                           PerlIO_printf( Perl_debug_log,
-                               "%*s  %sState: %4"UVxf", Base: %4"UVxf", Accepted: %4"UVxf" ",
-                               REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4],
-                               (UV)state, (UV)base, (UV)accepted );
-                   );
-
-                   if ( base ) {
-
-                       if ( do_utf8 ) {
-                           uvc = utf8n_to_uvuni( (U8*)uc, UTF8_MAXLEN, &len, uniflags );
-                       } else {
-                           uvc = (U32)*uc;
-                           len = 1;
-                       }
-
-                        TRIE_HANDLE_CHAR;
-
-                   } else {
-                       state = 0;
-                   }
-                   DEBUG_TRIE_EXECUTE_r(
-                           PerlIO_printf( Perl_debug_log,
-                               "Charid:%3x CV:%4"UVxf" After State: %4"UVxf"%s\n",
-                               charid, uvc, (UV)state, PL_colors[5] );
-                   );
-               }
-               if ( !accepted ) {
+               if (!st->u.trie.accepted )

                   sayNO;
                   sayNO;

-               }
-           }
-

 
            /*
               There was at least one accepting state that we
 
            /*
               There was at least one accepting state that we


@@ -2713,62 +2815,63 @@ S_regmatch(pTHX_ regnode *prog)
               eventually terminates once all of the accepting states
               have been tried.
            */
               eventually terminates once all of the accepting states
               have been tried.
            */

-       TrieAccept:
-           {
-               int gotit = 0;

 
 

-               if ( accepted == 1 ) {
+               if ( st->u.trie.accepted == 1 ) {

                    DEBUG_EXECUTE_r({
                    DEBUG_EXECUTE_r({

-                        SV **tmp = av_fetch( trie->words, accept_buff[ 0 ].wordnum-1, 0 );
+                        SV ** const tmp = av_fetch( trie->words, st->u.trie.accept_buff[ 0 ].wordnum-1, 0 );

                                PerlIO_printf( Perl_debug_log,
                            "%*s  %sonly one match : #%d <%s>%s\n",
                            REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4],
                                PerlIO_printf( Perl_debug_log,
                            "%*s  %sonly one match : #%d <%s>%s\n",
                            REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4],

-                           accept_buff[ 0 ].wordnum,
+                           st->u.trie.accept_buff[ 0 ].wordnum,

                            tmp ? SvPV_nolen_const( *tmp ) : "not compiled under -Dr",
                            PL_colors[5] );
                    });
                            tmp ? SvPV_nolen_const( *tmp ) : "not compiled under -Dr",
                            PL_colors[5] );
                    });

-                   PL_reginput = (char *)accept_buff[ 0 ].endpos;
+                   PL_reginput = (char *)st->u.trie.accept_buff[ 0 ].endpos;

                    /* in this case we free tmps/leave before we call regmatch
                       as we wont be using accept_buff again. */
                    FREETMPS;
                    LEAVE;
                    /* in this case we free tmps/leave before we call regmatch
                       as we wont be using accept_buff again. */
                    FREETMPS;
                    LEAVE;

-                   gotit = regmatch( scan + NEXT_OFF( scan ) );
+                   REGMATCH(scan + NEXT_OFF(scan), TRIE1);
+                   /*** all unsaved local vars undefined at this point */

                } else {
                     DEBUG_EXECUTE_r(
                         PerlIO_printf( Perl_debug_log,"%*s  %sgot %"IVdf" possible matches%s\n",
                } else {
                     DEBUG_EXECUTE_r(
                         PerlIO_printf( Perl_debug_log,"%*s  %sgot %"IVdf" possible matches%s\n",

-                            REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4], (IV)accepted,
+                            REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4], (IV)st->u.trie.accepted,

                             PL_colors[5] );
                     );
                             PL_colors[5] );
                     );

-                   while ( !gotit && accepted-- ) {
+                   while ( !result && st->u.trie.accepted-- ) {

                        U32 best = 0;
                        U32 cur;
                        U32 best = 0;
                        U32 cur;

-                       for( cur = 1 ; cur <= accepted ; cur++ ) {
+                       for( cur = 1 ; cur <= st->u.trie.accepted ; cur++ ) {

                            DEBUG_TRIE_EXECUTE_r(
                                PerlIO_printf( Perl_debug_log,
                                    "%*s  %sgot %"IVdf" (%d) as best, looking at %"IVdf" (%d)%s\n",
                                    REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4],
                            DEBUG_TRIE_EXECUTE_r(
                                PerlIO_printf( Perl_debug_log,
                                    "%*s  %sgot %"IVdf" (%d) as best, looking at %"IVdf" (%d)%s\n",
                                    REPORT_CODE_OFF + PL_regindent * 2, "", PL_colors[4],

-                                   (IV)best, accept_buff[ best ].wordnum, (IV)cur,
-                                   accept_buff[ cur ].wordnum, PL_colors[5] );
+                                   (IV)best, st->u.trie.accept_buff[ best ].wordnum, (IV)cur,
+                                   st->u.trie.accept_buff[ cur ].wordnum, PL_colors[5] );

                            );
 
                            );
 

-                           if ( accept_buff[ cur ].wordnum < accept_buff[ best ].wordnum )
-                                   best = cur;
+                           if (st->u.trie.accept_buff[cur].wordnum <
+                                   st->u.trie.accept_buff[best].wordnum)
+                               best = cur;

                        }
                        DEBUG_EXECUTE_r({
                        }
                        DEBUG_EXECUTE_r({

-                           SV **tmp = av_fetch( trie->words, accept_buff[ best ].wordnum - 1, 0 );
+                           reg_trie_data * const trie = (reg_trie_data*)
+                                           rex->data->data[ARG(scan)];
+                           SV ** const tmp = av_fetch( trie->words, st->u.trie.accept_buff[ best ].wordnum - 1, 0 );

                            PerlIO_printf( Perl_debug_log, "%*s  %strying alternation #%d <%s> at 0x%p%s\n",
                                REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4],
                            PerlIO_printf( Perl_debug_log, "%*s  %strying alternation #%d <%s> at 0x%p%s\n",
                                REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4],

-                               accept_buff[best].wordnum,
+                               st->u.trie.accept_buff[best].wordnum,

                                tmp ? SvPV_nolen_const( *tmp ) : "not compiled under -Dr",scan,
                                PL_colors[5] );
                        });
                                tmp ? SvPV_nolen_const( *tmp ) : "not compiled under -Dr",scan,
                                PL_colors[5] );
                        });

-                       if ( best<accepted ) {
-                           reg_trie_accepted tmp = accept_buff[ best ];
-                           accept_buff[ best ] = accept_buff[ accepted ];
-                           accept_buff[ accepted ] = tmp;
-                           best = accepted;
+                       if ( best<st->u.trie.accepted ) {
+                           reg_trie_accepted tmp = st->u.trie.accept_buff[ best ];
+                           st->u.trie.accept_buff[ best ] = st->u.trie.accept_buff[ st->u.trie.accepted ];
+                           st->u.trie.accept_buff[ st->u.trie.accepted ] = tmp;
+                           best = st->u.trie.accepted;

                        }
                        }

-                       PL_reginput = (char *)accept_buff[ best ].endpos;
+                       PL_reginput = (char *)st->u.trie.accept_buff[ best ].endpos;

 
                         /* 
                            as far as I can tell we only need the SAVETMPS/FREETMPS 
 
                         /* 
                            as far as I can tell we only need the SAVETMPS/FREETMPS 


@@ -2776,27 +2879,28 @@ S_regmatch(pTHX_ regnode *prog)
                            all until I can be sure.
                          */
                        SAVETMPS;
                            all until I can be sure.
                          */
                        SAVETMPS;

-                       gotit = regmatch( scan + NEXT_OFF( scan ) ) ;
+                       REGMATCH(scan + NEXT_OFF(scan), TRIE2);
+                       /*** all unsaved local vars undefined at this point */

                        FREETMPS;
                    }
                    FREETMPS;
                    LEAVE;
                }
                
                        FREETMPS;
                    }
                    FREETMPS;
                    LEAVE;
                }
                

-               if ( gotit ) {
+               if (result) {

                    sayYES;
                } else {
                    sayNO;
                }
            }
            /* unreached codepoint */
                    sayYES;
                } else {
                    sayNO;
                }
            }
            /* unreached codepoint */

-       case EXACT:
-           s = STRING(scan);
-           ln = STR_LEN(scan);
+       case EXACT: {
+           char *s = STRING(scan);
+           st->ln = STR_LEN(scan);

            if (do_utf8 != UTF) {
                /* The target and the pattern have differing utf8ness. */
                char *l = locinput;
            if (do_utf8 != UTF) {
                /* The target and the pattern have differing utf8ness. */
                char *l = locinput;

-               const char *e = s + ln;
+               const char *e = s + st->ln;

 
                if (do_utf8) {
                    /* The target is utf8, the pattern is not utf8. */
 
                if (do_utf8) {
                    /* The target is utf8, the pattern is not utf8. */


@@ -2834,26 +2938,27 @@ S_regmatch(pTHX_ regnode *prog)
            /* Inline the first character, for speed. */
            if (UCHARAT(s) != nextchr)
                sayNO;
            /* Inline the first character, for speed. */
            if (UCHARAT(s) != nextchr)
                sayNO;

-           if (PL_regeol - locinput < ln)
+           if (PL_regeol - locinput < st->ln)

                sayNO;
                sayNO;

-           if (ln > 1 && memNE(s, locinput, ln))
+           if (st->ln > 1 && memNE(s, locinput, st->ln))

                sayNO;
                sayNO;

-           locinput += ln;
+           locinput += st->ln;

            nextchr = UCHARAT(locinput);
            break;
            nextchr = UCHARAT(locinput);
            break;

+           }

        case EXACTFL:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case EXACTFL:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */

-       case EXACTF:
-           s = STRING(scan);
-           ln = STR_LEN(scan);
+       case EXACTF: {
+           char *s = STRING(scan);
+           st->ln = STR_LEN(scan);

 
            if (do_utf8 || UTF) {
              /* Either target or the pattern are utf8. */
                char *l = locinput;
                char *e = PL_regeol;
 
 
            if (do_utf8 || UTF) {
              /* Either target or the pattern are utf8. */
                char *l = locinput;
                char *e = PL_regeol;
 

-               if (ibcmp_utf8(s, 0,  ln, (bool)UTF,
+               if (ibcmp_utf8(s, 0,  st->ln, (bool)UTF,

                               l, &e, 0,  do_utf8)) {
                     /* One more case for the sharp s:
                      * pack("U0U*", 0xDF) =~ /ss/i,
                               l, &e, 0,  do_utf8)) {
                     /* One more case for the sharp s:
                      * pack("U0U*", 0xDF) =~ /ss/i,


@@ -2861,7 +2966,7 @@ S_regmatch(pTHX_ regnode *prog)
                      * byte sequence for the U+00DF. */
                     if (!(do_utf8 &&
                           toLOWER(s[0]) == 's' &&
                      * byte sequence for the U+00DF. */
                     if (!(do_utf8 &&
                           toLOWER(s[0]) == 's' &&

-                          ln >= 2 &&
+                          st->ln >= 2 &&

                           toLOWER(s[1]) == 's' &&
                           (U8)l[0] == 0xC3 &&
                           e - l >= 2 &&
                           toLOWER(s[1]) == 's' &&
                           (U8)l[0] == 0xC3 &&
                           e - l >= 2 &&


@@ -2880,20 +2985,21 @@ S_regmatch(pTHX_ regnode *prog)
                UCHARAT(s) != ((OP(scan) == EXACTF)
                               ? PL_fold : PL_fold_locale)[nextchr])
                sayNO;
                UCHARAT(s) != ((OP(scan) == EXACTF)
                               ? PL_fold : PL_fold_locale)[nextchr])
                sayNO;

-           if (PL_regeol - locinput < ln)
+           if (PL_regeol - locinput < st->ln)

                sayNO;
                sayNO;

-           if (ln > 1 && (OP(scan) == EXACTF
-                          ? ibcmp(s, locinput, ln)
-                          : ibcmp_locale(s, locinput, ln)))
+           if (st->ln > 1 && (OP(scan) == EXACTF
+                          ? ibcmp(s, locinput, st->ln)
+                          : ibcmp_locale(s, locinput, st->ln)))

                sayNO;
                sayNO;

-           locinput += ln;
+           locinput += st->ln;

            nextchr = UCHARAT(locinput);
            break;
            nextchr = UCHARAT(locinput);
            break;

+           }

        case ANYOF:
            if (do_utf8) {
                STRLEN inclasslen = PL_regeol - locinput;
 
        case ANYOF:
            if (do_utf8) {
                STRLEN inclasslen = PL_regeol - locinput;
 

-               if (!reginclass(scan, (U8*)locinput, &inclasslen, do_utf8))
+               if (!reginclass(rex, scan, (U8*)locinput, &inclasslen, do_utf8))

                    sayNO_ANYOF;
                if (locinput >= PL_regeol)
                    sayNO;
                    sayNO_ANYOF;
                if (locinput >= PL_regeol)
                    sayNO;


@@ -2904,7 +3010,7 @@ S_regmatch(pTHX_ regnode *prog)
            else {
                if (nextchr < 0)
                    nextchr = UCHARAT(locinput);
            else {
                if (nextchr < 0)
                    nextchr = UCHARAT(locinput);

-               if (!REGINCLASS(scan, (U8*)locinput))
+               if (!REGINCLASS(rex, scan, (U8*)locinput))

                    sayNO_ANYOF;
                if (!nextchr && locinput >= PL_regeol)
                    sayNO;
                    sayNO_ANYOF;
                if (!nextchr && locinput >= PL_regeol)
                    sayNO;


@@ -2977,35 +3083,35 @@ S_regmatch(pTHX_ regnode *prog)
            /* was last char in word? */
            if (do_utf8) {
                if (locinput == PL_bostr)
            /* was last char in word? */
            if (do_utf8) {
                if (locinput == PL_bostr)

-                   ln = '\n';
+                   st->ln = '\n';

                else {
                    const U8 * const r = reghop3((U8*)locinput, -1, (U8*)PL_bostr);
                
                else {
                    const U8 * const r = reghop3((U8*)locinput, -1, (U8*)PL_bostr);
                

-                   ln = utf8n_to_uvchr(r, UTF8SKIP(r), 0, 0);
+                   st->ln = utf8n_to_uvchr(r, UTF8SKIP(r), 0, uniflags);

                }
                if (OP(scan) == BOUND || OP(scan) == NBOUND) {
                }
                if (OP(scan) == BOUND || OP(scan) == NBOUND) {

-                   ln = isALNUM_uni(ln);
+                   st->ln = isALNUM_uni(st->ln);

                    LOAD_UTF8_CHARCLASS_ALNUM();
                    n = swash_fetch(PL_utf8_alnum, (U8*)locinput, do_utf8);
                }
                else {
                    LOAD_UTF8_CHARCLASS_ALNUM();
                    n = swash_fetch(PL_utf8_alnum, (U8*)locinput, do_utf8);
                }
                else {

-                   ln = isALNUM_LC_uvchr(UNI_TO_NATIVE(ln));
+                   st->ln = isALNUM_LC_uvchr(UNI_TO_NATIVE(st->ln));

                    n = isALNUM_LC_utf8((U8*)locinput);
                }
            }
            else {
                    n = isALNUM_LC_utf8((U8*)locinput);
                }
            }
            else {

-               ln = (locinput != PL_bostr) ?
+               st->ln = (locinput != PL_bostr) ?

                    UCHARAT(locinput - 1) : '\n';
                if (OP(scan) == BOUND || OP(scan) == NBOUND) {
                    UCHARAT(locinput - 1) : '\n';
                if (OP(scan) == BOUND || OP(scan) == NBOUND) {

-                   ln = isALNUM(ln);
+                   st->ln = isALNUM(st->ln);

                    n = isALNUM(nextchr);
                }
                else {
                    n = isALNUM(nextchr);
                }
                else {

-                   ln = isALNUM_LC(ln);
+                   st->ln = isALNUM_LC(st->ln);

                    n = isALNUM_LC(nextchr);
                }
            }
                    n = isALNUM_LC(nextchr);
                }
            }

-           if (((!ln) == (!n)) == (OP(scan) == BOUND ||
+           if (((!st->ln) == (!n)) == (OP(scan) == BOUND ||

                                    OP(scan) == BOUNDL))
                    sayNO;
            break;
                                    OP(scan) == BOUNDL))
                    sayNO;
            break;


@@ -3131,16 +3237,17 @@ S_regmatch(pTHX_ regnode *prog)
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
         case REF:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
         case REF:

-       case REFF:
+       case REFF: {
+           char *s;

            n = ARG(scan);  /* which paren pair */
            n = ARG(scan);  /* which paren pair */

-           ln = PL_regstartp[n];
+           st->ln = PL_regstartp[n];

            PL_reg_leftiter = PL_reg_maxiter;           /* Void cache */
            PL_reg_leftiter = PL_reg_maxiter;           /* Void cache */

-           if ((I32)*PL_reglastparen < n || ln == -1)
+           if ((I32)*PL_reglastparen < n || st->ln == -1)

                sayNO;                  /* Do not match unless seen CLOSEn. */
                sayNO;                  /* Do not match unless seen CLOSEn. */

-           if (ln == PL_regendp[n])
+           if (st->ln == PL_regendp[n])

                break;
 
                break;
 

-           s = PL_bostr + ln;
+           s = PL_bostr + st->ln;

            if (do_utf8 && OP(scan) != REF) {   /* REF can do byte comparison */
                char *l = locinput;
                const char *e = PL_bostr + PL_regendp[n];
            if (do_utf8 && OP(scan) != REF) {   /* REF can do byte comparison */
                char *l = locinput;
                const char *e = PL_bostr + PL_regendp[n];


@@ -3176,18 +3283,19 @@ S_regmatch(pTHX_ regnode *prog)
                 (UCHARAT(s) != ((OP(scan) == REFF
                                  ? PL_fold : PL_fold_locale)[nextchr]))))
                sayNO;
                 (UCHARAT(s) != ((OP(scan) == REFF
                                  ? PL_fold : PL_fold_locale)[nextchr]))))
                sayNO;

-           ln = PL_regendp[n] - ln;
-           if (locinput + ln > PL_regeol)
+           st->ln = PL_regendp[n] - st->ln;
+           if (locinput + st->ln > PL_regeol)

                sayNO;
                sayNO;

-           if (ln > 1 && (OP(scan) == REF
-                          ? memNE(s, locinput, ln)
+           if (st->ln > 1 && (OP(scan) == REF
+                          ? memNE(s, locinput, st->ln)

                           : (OP(scan) == REFF
                           : (OP(scan) == REFF

-                             ? ibcmp(s, locinput, ln)
-                             : ibcmp_locale(s, locinput, ln))))
+                             ? ibcmp(s, locinput, st->ln)
+                             : ibcmp_locale(s, locinput, st->ln))))

                sayNO;
                sayNO;

-           locinput += ln;
+           locinput += st->ln;

            nextchr = UCHARAT(locinput);
            break;
            nextchr = UCHARAT(locinput);
            break;

+           }

 
        case NOTHING:
        case TAIL:
 
        case NOTHING:
        case TAIL:


@@ -3196,21 +3304,21 @@ S_regmatch(pTHX_ regnode *prog)
            break;
        case EVAL:
        {
            break;
        case EVAL:
        {

-           dSP;
-           OP_4tree *oop = PL_op;
-           COP *ocurcop = PL_curcop;
-           PAD *old_comppad;

            SV *ret;
            SV *ret;

-           struct regexp *oreg = PL_reg_re;
-       
-           n = ARG(scan);
-           PL_op = (OP_4tree*)PL_regdata->data[n];
-           DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, "  re_eval 0x%"UVxf"\n", PTR2UV(PL_op)) );
-           PAD_SAVE_LOCAL(old_comppad, (PAD*)PL_regdata->data[n + 2]);
-           PL_regendp[0] = PL_reg_magic->mg_len = locinput - PL_bostr;
-

            {
            {

-               SV **before = SP;
+               /* execute the code in the {...} */
+               dSP;
+               SV ** const before = SP;
+               OP_4tree * const oop = PL_op;
+               COP * const ocurcop = PL_curcop;
+               PAD *old_comppad;
+           
+               n = ARG(scan);
+               PL_op = (OP_4tree*)rex->data->data[n];
+               DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, "  re_eval 0x%"UVxf"\n", PTR2UV(PL_op)) );
+               PAD_SAVE_LOCAL(old_comppad, (PAD*)rex->data->data[n + 2]);
+               PL_regendp[0] = PL_reg_magic->mg_len = locinput - PL_bostr;
+

                CALLRUNOPS(aTHX);                       /* Scalar context. */
                SPAGAIN;
                if (SP == before)
                CALLRUNOPS(aTHX);                       /* Scalar context. */
                SPAGAIN;
                if (SP == before)


@@ -3219,20 +3327,24 @@ S_regmatch(pTHX_ regnode *prog)
                    ret = POPs;
                    PUTBACK;
                }
                    ret = POPs;
                    PUTBACK;
                }

-           }

 
 

-           PL_op = oop;
-           PAD_RESTORE_LOCAL(old_comppad);
-           PL_curcop = ocurcop;
-           if (logical) {
-               if (logical == 2) {     /* Postponed subexpression. */
-                   regexp *re;
-                   MAGIC *mg = Null(MAGIC*);
-                   re_cc_state state;
-                   CHECKPOINT cp, lastcp;
-                    int toggleutf;
-                   register SV *sv;
+               PL_op = oop;
+               PAD_RESTORE_LOCAL(old_comppad);
+               PL_curcop = ocurcop;
+               if (!st->logical) {
+                   /* /(?{...})/ */
+                   sv_setsv(save_scalar(PL_replgv), ret);
+                   break;
+               }
+           }
+           if (st->logical == 2) { /* Postponed subexpression: /(??{...})/ */
+               regexp *re;
+               {
+                   /* extract RE object from returned value; compiling if
+                    * necessary */

 
 

+                   MAGIC *mg = NULL;
+                   SV *sv;

                    if(SvROK(ret) && SvSMAGICAL(sv = SvRV(ret)))
                        mg = mg_find(sv, PERL_MAGIC_qr);
                    else if (SvSMAGICAL(ret)) {
                    if(SvROK(ret) && SvSMAGICAL(sv = SvRV(ret)))
                        mg = mg_find(sv, PERL_MAGIC_qr);
                    else if (SvSMAGICAL(ret)) {


@@ -3248,96 +3360,63 @@ S_regmatch(pTHX_ regnode *prog)
                    }
                    else {
                        STRLEN len;
                    }
                    else {
                        STRLEN len;

-                       const char *t = SvPV_const(ret, len);
+                       const char * const t = SvPV_const(ret, len);

                        PMOP pm;
                        PMOP pm;

-                       char * const oprecomp = PL_regprecomp;

                        const I32 osize = PL_regsize;
                        const I32 osize = PL_regsize;

-                       const I32 onpar = PL_regnpar;

 
                        Zero(&pm, 1, PMOP);
 
                        Zero(&pm, 1, PMOP);

-                        if (DO_UTF8(ret)) pm.op_pmdynflags |= PMdf_DYN_UTF8;
+                       if (DO_UTF8(ret)) pm.op_pmdynflags |= PMdf_DYN_UTF8;

                        re = CALLREGCOMP(aTHX_ (char*)t, (char*)t + len, &pm);
                        if (!(SvFLAGS(ret)
                              & (SVs_TEMP | SVs_PADTMP | SVf_READONLY
                                | SVs_GMG)))
                            sv_magic(ret,(SV*)ReREFCNT_inc(re),
                                        PERL_MAGIC_qr,0,0);
                        re = CALLREGCOMP(aTHX_ (char*)t, (char*)t + len, &pm);
                        if (!(SvFLAGS(ret)
                              & (SVs_TEMP | SVs_PADTMP | SVf_READONLY
                                | SVs_GMG)))
                            sv_magic(ret,(SV*)ReREFCNT_inc(re),
                                        PERL_MAGIC_qr,0,0);

-                       PL_regprecomp = oprecomp;

                        PL_regsize = osize;
                        PL_regsize = osize;

-                       PL_regnpar = onpar;

                    }
                    }

-                   DEBUG_EXECUTE_r(
-                       PerlIO_printf(Perl_debug_log,
-                                     "Entering embedded \"%s%.60s%s%s\"\n",
-                                     PL_colors[0],
-                                     re->precomp,
-                                     PL_colors[1],
-                                     (strlen(re->precomp) > 60 ? "..." : ""))
-                       );
-                   state.node = next;
-                   state.prev = PL_reg_call_cc;
-                   state.cc = PL_regcc;
-                   state.re = PL_reg_re;
-
-                   PL_regcc = 0;
-               
-                   cp = regcppush(0);  /* Save *all* the positions. */
-                   REGCP_SET(lastcp);
-                   cache_re(re);
-                   state.ss = PL_savestack_ix;
-                   *PL_reglastparen = 0;
-                   *PL_reglastcloseparen = 0;
-                   PL_reg_call_cc = &state;
-                   PL_reginput = locinput;
-                   toggleutf = ((PL_reg_flags & RF_utf8) != 0) ^
-                               ((re->reganch & ROPT_UTF8) != 0);
-                   if (toggleutf) PL_reg_flags ^= RF_utf8;
-
-                   /* XXXX This is too dramatic a measure... */
-                   PL_reg_maxiter = 0;
-
-                   if (regmatch(re->program + 1)) {
-                       /* Even though we succeeded, we need to restore
-                          global variables, since we may be wrapped inside
-                          SUSPEND, thus the match may be not finished yet. */
-
-                       /* XXXX Do this only if SUSPENDed? */
-                       PL_reg_call_cc = state.prev;
-                       PL_regcc = state.cc;
-                       PL_reg_re = state.re;
-                       cache_re(PL_reg_re);
-                       if (toggleutf) PL_reg_flags ^= RF_utf8;
-
-                       /* XXXX This is too dramatic a measure... */
-                       PL_reg_maxiter = 0;
-
-                       /* These are needed even if not SUSPEND. */
-                       ReREFCNT_dec(re);
-                       regcpblow(cp);
-                       sayYES;
-                   }
-                   ReREFCNT_dec(re);
-                   REGCP_UNWIND(lastcp);
-                   regcppop();
-                   PL_reg_call_cc = state.prev;
-                   PL_regcc = state.cc;
-                   PL_reg_re = state.re;
-                   cache_re(PL_reg_re);
-                   if (toggleutf) PL_reg_flags ^= RF_utf8;
-
-                   /* XXXX This is too dramatic a measure... */
-                   PL_reg_maxiter = 0;
-
-                   logical = 0;
-                   sayNO;

                }
                }

-               sw = SvTRUE(ret);
-               logical = 0;
-           }
-           else {
-               sv_setsv(save_scalar(PL_replgv), ret);
-               cache_re(oreg);
+
+               /* run the pattern returned from (??{...}) */
+
+               DEBUG_EXECUTE_r(
+                   PerlIO_printf(Perl_debug_log,
+                                 "Entering embedded \"%s%.60s%s%s\"\n",
+                                 PL_colors[0],
+                                 re->precomp,
+                                 PL_colors[1],
+                                 (strlen(re->precomp) > 60 ? "..." : ""))
+                   );
+
+               st->u.eval.cp = regcppush(0);   /* Save *all* the positions. */
+               REGCP_SET(st->u.eval.lastcp);
+               *PL_reglastparen = 0;
+               *PL_reglastcloseparen = 0;
+               PL_reginput = locinput;
+
+               /* XXXX This is too dramatic a measure... */
+               PL_reg_maxiter = 0;
+
+               st->logical = 0;
+               st->u.eval.toggleutf = ((PL_reg_flags & RF_utf8) != 0) ^
+                           ((re->reganch & ROPT_UTF8) != 0);
+               if (st->u.eval.toggleutf) PL_reg_flags ^= RF_utf8;
+               st->u.eval.prev_rex = rex;
+               rex = re;
+
+               /* resume to current state on success */
+               st->u.yes.prev_yes_state = yes_state;
+               yes_state = st;
+               PUSH_STATE(newst, resume_EVAL);
+               st = newst;
+
+               /* now continue  from first node in postoned RE */
+               next = re->program + 1;
+               break;
+               /* NOTREACHED */

            }
            }

+           /* /(?(?{...})X|Y)/ */
+           st->sw = SvTRUE(ret);
+           st->logical = 0;

            break;
        }
        case OPEN:
            break;
        }
        case OPEN:


@@ -3356,11 +3435,11 @@ S_regmatch(pTHX_ regnode *prog)
            break;
        case GROUPP:
            n = ARG(scan);  /* which paren pair */
            break;
        case GROUPP:
            n = ARG(scan);  /* which paren pair */

-           sw = ((I32)*PL_reglastparen >= n && PL_regendp[n] != -1);
+           st->sw = ((I32)*PL_reglastparen >= n && PL_regendp[n] != -1);

            break;
        case IFTHEN:
            PL_reg_leftiter = PL_reg_maxiter;           /* Void cache */
            break;
        case IFTHEN:
            PL_reg_leftiter = PL_reg_maxiter;           /* Void cache */

-           if (sw)
+           if (st->sw)

                next = NEXTOPER(NEXTOPER(scan));
            else {
                next = scan + ARG(scan);
                next = NEXTOPER(NEXTOPER(scan));
            else {
                next = scan + ARG(scan);


@@ -3369,38 +3448,39 @@ S_regmatch(pTHX_ regnode *prog)
            }
            break;
        case LOGICAL:
            }
            break;
        case LOGICAL:

-           logical = scan->flags;
+           st->logical = scan->flags;

            break;
 /*******************************************************************
            break;
 /*******************************************************************

- PL_regcc contains infoblock about the innermost (...)* loop, and
- a pointer to the next outer infoblock.
+ cc points to the regmatch_state associated with the most recent CURLYX.
+ This struct contains info about the innermost (...)* loop (an
+ "infoblock"), and a pointer to the next outer cc.

 
  Here is how Y(A)*Z is processed (if it is compiled into CURLYX/WHILEM):
 
 
  Here is how Y(A)*Z is processed (if it is compiled into CURLYX/WHILEM):
 

-   1) After matching X, regnode for CURLYX is processed;
+   1) After matching Y, regnode for CURLYX is processed;

 
 

-   2) This regnode creates infoblock on the stack, and calls
-      regmatch() recursively with the starting point at WHILEM node;
+   2) This regnode populates cc, and calls regmatch() recursively
+      with the starting point at WHILEM node;

 
    3) Each hit of WHILEM node tries to match A and Z (in the order
       depending on the current iteration, min/max of {min,max} and
       greediness).  The information about where are nodes for "A"
 
    3) Each hit of WHILEM node tries to match A and Z (in the order
       depending on the current iteration, min/max of {min,max} and
       greediness).  The information about where are nodes for "A"

-      and "Z" is read from the infoblock, as is info on how many times "A"
+      and "Z" is read from cc, as is info on how many times "A"

       was already matched, and greediness.
 
    4) After A matches, the same WHILEM node is hit again.
 
       was already matched, and greediness.
 
    4) After A matches, the same WHILEM node is hit again.
 

-   5) Each time WHILEM is hit, PL_regcc is the infoblock created by CURLYX
+   5) Each time WHILEM is hit, cc is the infoblock created by CURLYX

       of the same pair.  Thus when WHILEM tries to match Z, it temporarily
       of the same pair.  Thus when WHILEM tries to match Z, it temporarily

-      resets PL_regcc, since this Y(A)*Z can be a part of some other loop:
+      resets cc, since this Y(A)*Z can be a part of some other loop:

       as in (Y(A)*Z)*.  If Z matches, the automaton will hit the WHILEM node
       of the external loop.
 
       as in (Y(A)*Z)*.  If Z matches, the automaton will hit the WHILEM node
       of the external loop.
 

- Currently present infoblocks form a tree with a stem formed by PL_curcc
+ Currently present infoblocks form a tree with a stem formed by st->cc

  and whatever it mentions via ->next, and additional attached trees
  corresponding to temporarily unset infoblocks as in "5" above.
 
  and whatever it mentions via ->next, and additional attached trees
  corresponding to temporarily unset infoblocks as in "5" above.
 

- In the following picture infoblocks for outer loop of
+ In the following picture, infoblocks for outer loop of

  (Y(A)*?Z)*?T are denoted O, for inner I.  NULL starting block
  is denoted by x.  The matched string is YAAZYAZT.  Temporarily postponed
  infoblocks are drawn below the "reset" infoblock.
  (Y(A)*?Z)*?T are denoted O, for inner I.  NULL starting block
  is denoted by x.  The matched string is YAAZYAZT.  Temporarily postponed
  infoblocks are drawn below the "reset" infoblock.


@@ -3446,35 +3526,40 @@ S_regmatch(pTHX_ regnode *prog)
                                O
                                I,I
  *******************************************************************/
                                O
                                I,I
  *******************************************************************/

+

        case CURLYX: {
        case CURLYX: {

-               CURCUR cc;
-               CHECKPOINT cp = PL_savestack_ix;

                /* No need to save/restore up to this paren */
                I32 parenfloor = scan->flags;
 
                if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */
                    next += ARG(next);
                /* No need to save/restore up to this paren */
                I32 parenfloor = scan->flags;
 
                if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */
                    next += ARG(next);

-               cc.oldcc = PL_regcc;
-               PL_regcc = &cc;

                /* XXXX Probably it is better to teach regpush to support
                   parenfloor > PL_regsize... */
                if (parenfloor > (I32)*PL_reglastparen)
                    parenfloor = *PL_reglastparen; /* Pessimization... */
                /* XXXX Probably it is better to teach regpush to support
                   parenfloor > PL_regsize... */
                if (parenfloor > (I32)*PL_reglastparen)
                    parenfloor = *PL_reglastparen; /* Pessimization... */

-               cc.parenfloor = parenfloor;
-               cc.cur = -1;
-               cc.min = ARG1(scan);
-               cc.max  = ARG2(scan);
-               cc.scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
-               cc.next = next;
-               cc.minmod = minmod;
-               cc.lastloc = 0;
+
+               st->u.curlyx.cp = PL_savestack_ix;
+               st->u.curlyx.outercc = st->cc;
+               st->cc = st;
+               /* these fields contain the state of the current curly.
+                * they are accessed by subsequent WHILEMs;
+                * cur and lastloc are also updated by WHILEM */
+               st->u.curlyx.parenfloor = parenfloor;
+               st->u.curlyx.cur = -1; /* this will be updated by WHILEM */
+               st->u.curlyx.min = ARG1(scan);
+               st->u.curlyx.max  = ARG2(scan);
+               st->u.curlyx.scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
+               st->u.curlyx.lastloc = 0;
+               /* st->next and st->minmod are also read by WHILEM */
+

                PL_reginput = locinput;
                PL_reginput = locinput;

-               n = regmatch(PREVOPER(next));   /* start on the WHILEM */
-               regcpblow(cp);
-               PL_regcc = cc.oldcc;
-               saySAME(n);
+               REGMATCH(PREVOPER(next), CURLYX); /* start on the WHILEM */
+               /*** all unsaved local vars undefined at this point */
+               regcpblow(st->u.curlyx.cp);
+               st->cc = st->u.curlyx.outercc;
+               saySAME(result);

            }
            }

-           /* NOT REACHED */
+           /* NOTREACHED */

        case WHILEM: {
                /*
                 * This is really hard to understand, because after we match
        case WHILEM: {
                /*
                 * This is really hard to understand, because after we match


@@ -3485,50 +3570,54 @@ S_regmatch(pTHX_ regnode *prog)
                 * that we can try again after backing off.
                 */
 
                 * that we can try again after backing off.
                 */
 

-               CHECKPOINT cp, lastcp;
-               CURCUR* cc = PL_regcc;
-               char *lastloc = cc->lastloc; /* Detection of 0-len. */
-               I32 cache_offset = 0, cache_bit = 0;
+               st->u.whilem.lastloc = st->cc->u.curlyx.lastloc; /* Detection of 0-len. */
+               st->u.whilem.cache_offset = 0;
+               st->u.whilem.cache_bit = 0;

                
                

-               n = cc->cur + 1;        /* how many we know we matched */
+               n = st->cc->u.curlyx.cur + 1; /* how many we know we matched */

                PL_reginput = locinput;
 
                DEBUG_EXECUTE_r(
                    PerlIO_printf(Perl_debug_log,
                                  "%*s  %ld out of %ld..%ld  cc=%"UVxf"\n",
                                  REPORT_CODE_OFF+PL_regindent*2, "",
                PL_reginput = locinput;
 
                DEBUG_EXECUTE_r(
                    PerlIO_printf(Perl_debug_log,
                                  "%*s  %ld out of %ld..%ld  cc=%"UVxf"\n",
                                  REPORT_CODE_OFF+PL_regindent*2, "",

-                                 (long)n, (long)cc->min,
-                                 (long)cc->max, PTR2UV(cc))
+                                 (long)n, (long)st->cc->u.curlyx.min,
+                                 (long)st->cc->u.curlyx.max, PTR2UV(st->cc))

                    );
 
                /* If degenerate scan matches "", assume scan done. */
 
                    );
 
                /* If degenerate scan matches "", assume scan done. */
 

-               if (locinput == cc->lastloc && n >= cc->min) {
-                   PL_regcc = cc->oldcc;
-                   if (PL_regcc)
-                       ln = PL_regcc->cur;
+               if (locinput == st->cc->u.curlyx.lastloc && n >= st->cc->u.curlyx.min) {
+                   st->u.whilem.savecc = st->cc;
+                   st->cc = st->cc->u.curlyx.outercc;
+                   if (st->cc)
+                       st->ln = st->cc->u.curlyx.cur;

                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,
                           "%*s  empty match detected, try continuation...\n",
                           REPORT_CODE_OFF+PL_regindent*2, "")
                        );
                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,
                           "%*s  empty match detected, try continuation...\n",
                           REPORT_CODE_OFF+PL_regindent*2, "")
                        );

-                   if (regmatch(cc->next))
+                   REGMATCH(st->u.whilem.savecc->next, WHILEM1);
+                   /*** all unsaved local vars undefined at this point */
+                   st->cc = st->u.whilem.savecc;
+                   if (result)

                        sayYES;
                        sayYES;

-                   if (PL_regcc)
-                       PL_regcc->cur = ln;
-                   PL_regcc = cc;
+                   if (st->cc->u.curlyx.outercc)
+                       st->cc->u.curlyx.outercc->u.curlyx.cur = st->ln;

                    sayNO;
                }
 
                /* First just match a string of min scans. */
 
                    sayNO;
                }
 
                /* First just match a string of min scans. */
 

-               if (n < cc->min) {
-                   cc->cur = n;
-                   cc->lastloc = locinput;
-                   if (regmatch(cc->scan))
+               if (n < st->cc->u.curlyx.min) {
+                   st->cc->u.curlyx.cur = n;
+                   st->cc->u.curlyx.lastloc = locinput;
+                   REGMATCH(st->cc->u.curlyx.scan, WHILEM2);
+                   /*** all unsaved local vars undefined at this point */
+                   if (result)

                        sayYES;
                        sayYES;

-                   cc->cur = n - 1;
-                   cc->lastloc = lastloc;
+                   st->cc->u.curlyx.cur = n - 1;
+                   st->cc->u.curlyx.lastloc = st->u.whilem.lastloc;

                    sayNO;
                }
 
                    sayNO;
                }
 


@@ -3560,13 +3649,13 @@ S_regmatch(pTHX_ regnode *prog)
                        );
                }
                if (PL_reg_leftiter < 0) {
                        );
                }
                if (PL_reg_leftiter < 0) {

-                   cache_offset = locinput - PL_bostr;
+                   st->u.whilem.cache_offset = locinput - PL_bostr;

 
 

-                   cache_offset = (scan->flags & 0xf) - 1 + POSCACHE_START
-                           + cache_offset * (scan->flags>>4);
-                   cache_bit = cache_offset % 8;
-                   cache_offset /= 8;
-                   if (PL_reg_poscache[cache_offset] & (1<<cache_bit)) {
+                   st->u.whilem.cache_offset = (scan->flags & 0xf) - 1 + POSCACHE_START
+                           + st->u.whilem.cache_offset * (scan->flags>>4);
+                   st->u.whilem.cache_bit = st->u.whilem.cache_offset % 8;
+                   st->u.whilem.cache_offset /= 8;
+                   if (PL_reg_poscache[st->u.whilem.cache_offset] & (1<<st->u.whilem.cache_bit)) {

                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,
                                      "%*s  already tried at this position...\n",
                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,
                                      "%*s  already tried at this position...\n",


@@ -3579,29 +3668,32 @@ S_regmatch(pTHX_ regnode *prog)
                            /* cache records failure */
                            sayNO_SILENT;
                    }
                            /* cache records failure */
                            sayNO_SILENT;
                    }

-                   PL_reg_poscache[cache_offset] |= (1<<cache_bit);
+                   PL_reg_poscache[st->u.whilem.cache_offset] |= (1<<st->u.whilem.cache_bit);

                }
                }
 
                /* Prefer next over scan for minimal matching. */
 
                }
                }
 
                /* Prefer next over scan for minimal matching. */
 

-               if (cc->minmod) {
-                   PL_regcc = cc->oldcc;
-                   if (PL_regcc)
-                       ln = PL_regcc->cur;
-                   cp = regcppush(cc->parenfloor);
-                   REGCP_SET(lastcp);
-                   if (regmatch(cc->next)) {
-                       regcpblow(cp);
+               if (st->cc->minmod) {
+                   st->u.whilem.savecc = st->cc;
+                   st->cc = st->cc->u.curlyx.outercc;
+                   if (st->cc)
+                       st->ln = st->cc->u.curlyx.cur;
+                   st->u.whilem.cp = regcppush(st->u.whilem.savecc->u.curlyx.parenfloor);
+                   REGCP_SET(st->u.whilem.lastcp);
+                   REGMATCH(st->u.whilem.savecc->next, WHILEM3);
+                   /*** all unsaved local vars undefined at this point */
+                   st->cc = st->u.whilem.savecc;
+                   if (result) {
+                       regcpblow(st->u.whilem.cp);

                        CACHEsayYES;    /* All done. */
                    }
                        CACHEsayYES;    /* All done. */
                    }

-                   REGCP_UNWIND(lastcp);
-                   regcppop();
-                   if (PL_regcc)
-                       PL_regcc->cur = ln;
-                   PL_regcc = cc;
+                   REGCP_UNWIND(st->u.whilem.lastcp);
+                   regcppop(rex);
+                   if (st->cc->u.curlyx.outercc)
+                       st->cc->u.curlyx.outercc->u.curlyx.cur = st->ln;

 
 

-                   if (n >= cc->max) { /* Maximum greed exceeded? */
+                   if (n >= st->cc->u.curlyx.max) { /* Maximum greed exceeded? */

                        if (ckWARN(WARN_REGEXP) && n >= REG_INFTY
                            && !(PL_reg_flags & RF_warned)) {
                            PL_reg_flags |= RF_warned;
                        if (ckWARN(WARN_REGEXP) && n >= REG_INFTY
                            && !(PL_reg_flags & RF_warned)) {
                            PL_reg_flags |= RF_warned;


@@ -3619,34 +3711,38 @@ S_regmatch(pTHX_ regnode *prog)
                        );
                    /* Try scanning more and see if it helps. */
                    PL_reginput = locinput;
                        );
                    /* Try scanning more and see if it helps. */
                    PL_reginput = locinput;

-                   cc->cur = n;
-                   cc->lastloc = locinput;
-                   cp = regcppush(cc->parenfloor);
-                   REGCP_SET(lastcp);
-                   if (regmatch(cc->scan)) {
-                       regcpblow(cp);
+                   st->cc->u.curlyx.cur = n;
+                   st->cc->u.curlyx.lastloc = locinput;
+                   st->u.whilem.cp = regcppush(st->cc->u.curlyx.parenfloor);
+                   REGCP_SET(st->u.whilem.lastcp);
+                   REGMATCH(st->cc->u.curlyx.scan, WHILEM4);
+                   /*** all unsaved local vars undefined at this point */
+                   if (result) {
+                       regcpblow(st->u.whilem.cp);

                        CACHEsayYES;
                    }
                        CACHEsayYES;
                    }

-                   REGCP_UNWIND(lastcp);
-                   regcppop();
-                   cc->cur = n - 1;
-                   cc->lastloc = lastloc;
+                   REGCP_UNWIND(st->u.whilem.lastcp);
+                   regcppop(rex);
+                   st->cc->u.curlyx.cur = n - 1;
+                   st->cc->u.curlyx.lastloc = st->u.whilem.lastloc;

                    CACHEsayNO;
                }
 
                /* Prefer scan over next for maximal matching. */
 
                    CACHEsayNO;
                }
 
                /* Prefer scan over next for maximal matching. */
 

-               if (n < cc->max) {      /* More greed allowed? */
-                   cp = regcppush(cc->parenfloor);
-                   cc->cur = n;
-                   cc->lastloc = locinput;
-                   REGCP_SET(lastcp);
-                   if (regmatch(cc->scan)) {
-                       regcpblow(cp);
+               if (n < st->cc->u.curlyx.max) { /* More greed allowed? */
+                   st->u.whilem.cp = regcppush(st->cc->u.curlyx.parenfloor);
+                   st->cc->u.curlyx.cur = n;
+                   st->cc->u.curlyx.lastloc = locinput;
+                   REGCP_SET(st->u.whilem.lastcp);
+                   REGMATCH(st->cc->u.curlyx.scan, WHILEM5);
+                   /*** all unsaved local vars undefined at this point */
+                   if (result) {
+                       regcpblow(st->u.whilem.cp);

                        CACHEsayYES;
                    }
                        CACHEsayYES;
                    }

-                   REGCP_UNWIND(lastcp);
-                   regcppop();         /* Restore some previous $<digit>s? */
+                   REGCP_UNWIND(st->u.whilem.lastcp);
+                   regcppop(rex);      /* Restore some previous $<digit>s? */

                    PL_reginput = locinput;
                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,
                    PL_reginput = locinput;
                    DEBUG_EXECUTE_r(
                        PerlIO_printf(Perl_debug_log,


@@ -3663,19 +3759,22 @@ S_regmatch(pTHX_ regnode *prog)
                }
 
                /* Failed deeper matches of scan, so see if this one works. */
                }
 
                /* Failed deeper matches of scan, so see if this one works. */

-               PL_regcc = cc->oldcc;
-               if (PL_regcc)
-                   ln = PL_regcc->cur;
-               if (regmatch(cc->next))
+               st->u.whilem.savecc = st->cc;
+               st->cc = st->cc->u.curlyx.outercc;
+               if (st->cc)
+                   st->ln = st->cc->u.curlyx.cur;
+               REGMATCH(st->u.whilem.savecc->next, WHILEM6);
+               /*** all unsaved local vars undefined at this point */
+               st->cc = st->u.whilem.savecc;
+               if (result)

                    CACHEsayYES;
                    CACHEsayYES;

-               if (PL_regcc)
-                   PL_regcc->cur = ln;
-               PL_regcc = cc;
-               cc->cur = n - 1;
-               cc->lastloc = lastloc;
+               if (st->cc->u.curlyx.outercc)
+                   st->cc->u.curlyx.outercc->u.curlyx.cur = st->ln;
+               st->cc->u.curlyx.cur = n - 1;
+               st->cc->u.curlyx.lastloc = st->u.whilem.lastloc;

                CACHEsayNO;
            }
                CACHEsayNO;
            }

-           /* NOT REACHED */
+           /* NOTREACHED */

        case BRANCHJ:
            next = scan + ARG(scan);
            if (next == scan)
        case BRANCHJ:
            next = scan + ARG(scan);
            if (next == scan)


@@ -3686,26 +3785,26 @@ S_regmatch(pTHX_ regnode *prog)
            inner = NEXTOPER(scan);
          do_branch:
            {
            inner = NEXTOPER(scan);
          do_branch:
            {

-               c1 = OP(scan);
-               if (OP(next) != c1)     /* No choice. */
+               I32 type;
+               type = OP(scan);
+               if (!next || OP(next) != type)  /* No choice. */

                    next = inner;       /* Avoid recursion. */
                else {
                    const I32 lastparen = *PL_reglastparen;
                    next = inner;       /* Avoid recursion. */
                else {
                    const I32 lastparen = *PL_reglastparen;

-                   I32 unwind1;
-                   re_unwind_branch_t *uw;
-

                    /* Put unwinding data on stack */
                    /* Put unwinding data on stack */

-                   unwind1 = SSNEWt(1,re_unwind_branch_t);
-                   uw = SSPTRt(unwind1,re_unwind_branch_t);
-                   uw->prev = unwind;
-                   unwind = unwind1;
-                   uw->type = ((c1 == BRANCH)
+                   const I32 unwind1 = SSNEWt(1,re_unwind_branch_t);
+                   re_unwind_branch_t * const uw = SSPTRt(unwind1,re_unwind_branch_t);
+
+                   uw->prev = st->unwind;
+                   st->unwind = unwind1;
+                   uw->type = ((type == BRANCH)

                                ? RE_UNWIND_BRANCH
                                : RE_UNWIND_BRANCHJ);
                    uw->lastparen = lastparen;
                    uw->next = next;
                    uw->locinput = locinput;
                    uw->nextchr = nextchr;
                                ? RE_UNWIND_BRANCH
                                : RE_UNWIND_BRANCHJ);
                    uw->lastparen = lastparen;
                    uw->next = next;
                    uw->locinput = locinput;
                    uw->nextchr = nextchr;

+                   uw->minmod = st->minmod;

 #ifdef DEBUGGING
                    uw->regindent = ++PL_regindent;
 #endif
 #ifdef DEBUGGING
                    uw->regindent = ++PL_regindent;
 #endif


@@ -3718,81 +3817,113 @@ S_regmatch(pTHX_ regnode *prog)
            }
            break;
        case MINMOD:
            }
            break;
        case MINMOD:

-           minmod = 1;
+           st->minmod = 1;

            break;
        case CURLYM:
        {
            break;
        case CURLYM:
        {

-           I32 l = 0;
-           CHECKPOINT lastcp;
+           st->u.curlym.l = st->u.curlym.matches = 0;

        
            /* We suppose that the next guy does not need
               backtracking: in particular, it is of constant non-zero length,
               and has no parenths to influence future backrefs. */
        
            /* We suppose that the next guy does not need
               backtracking: in particular, it is of constant non-zero length,
               and has no parenths to influence future backrefs. */

-           ln = ARG1(scan);  /* min to match */
+           st->ln = ARG1(scan);  /* min to match */

            n  = ARG2(scan);  /* max to match */
            n  = ARG2(scan);  /* max to match */

-           paren = scan->flags;
-           if (paren) {
-               if (paren > PL_regsize)
-                   PL_regsize = paren;
-               if (paren > (I32)*PL_reglastparen)
-                   *PL_reglastparen = paren;
+           st->u.curlym.paren = scan->flags;
+           if (st->u.curlym.paren) {
+               if (st->u.curlym.paren > PL_regsize)
+                   PL_regsize = st->u.curlym.paren;
+               if (st->u.curlym.paren > (I32)*PL_reglastparen)
+                   *PL_reglastparen = st->u.curlym.paren;

            }
            scan = NEXTOPER(scan) + NODE_STEP_REGNODE;
            }
            scan = NEXTOPER(scan) + NODE_STEP_REGNODE;

-           if (paren)
+           if (st->u.curlym.paren)

                scan += NEXT_OFF(scan); /* Skip former OPEN. */
            PL_reginput = locinput;
                scan += NEXT_OFF(scan); /* Skip former OPEN. */
            PL_reginput = locinput;

-           if (minmod) {
-               minmod = 0;
-               if (ln && regrepeat_hard(scan, ln, &l) < ln)
+           st->u.curlym.maxwanted = st->minmod ? st->ln : n;
+           if (st->u.curlym.maxwanted) {
+               while (PL_reginput < PL_regeol && st->u.curlym.matches < st->u.curlym.maxwanted) {
+                   REGMATCH(scan, CURLYM1);
+                   /*** all unsaved local vars undefined at this point */
+                   if (!result)
+                       break;
+                   /* on first match, determine length, u.curlym.l */
+                   if (!st->u.curlym.matches++) {
+                       if (PL_reg_match_utf8) {
+                           char *s = locinput;
+                           while (s < PL_reginput) {
+                               st->u.curlym.l++;
+                               s += UTF8SKIP(s);
+                           }
+                       }
+                       else {
+                           st->u.curlym.l = PL_reginput - locinput;
+                       }
+                       if (st->u.curlym.l == 0) {
+                           st->u.curlym.matches = st->u.curlym.maxwanted;
+                           break;
+                       }
+                   }
+                   locinput = PL_reginput;
+               }
+           }
+
+           PL_reginput = locinput;
+
+           if (st->minmod) {
+               st->minmod = 0;
+               if (st->ln && st->u.curlym.matches < st->ln)

                    sayNO;
                    sayNO;

-               locinput = PL_reginput;

                if (HAS_TEXT(next) || JUMPABLE(next)) {
                    regnode *text_node = next;
 
                    if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
                if (HAS_TEXT(next) || JUMPABLE(next)) {
                    regnode *text_node = next;
 
                    if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 

-                   if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
+                   if (! HAS_TEXT(text_node)) st->u.curlym.c1 = st->u.curlym.c2 = -1000;

                    else {
                        if (PL_regkind[(U8)OP(text_node)] == REF) {
                    else {
                        if (PL_regkind[(U8)OP(text_node)] == REF) {

-                           c1 = c2 = -1000;
+                           st->u.curlym.c1 = st->u.curlym.c2 = -1000;

                            goto assume_ok_MM;
                        }
                            goto assume_ok_MM;
                        }

-                       else { c1 = (U8)*STRING(text_node); }
+                       else { st->u.curlym.c1 = (U8)*STRING(text_node); }

                        if (OP(text_node) == EXACTF || OP(text_node) == REFF)
                        if (OP(text_node) == EXACTF || OP(text_node) == REFF)

-                           c2 = PL_fold[c1];
+                           st->u.curlym.c2 = PL_fold[st->u.curlym.c1];

                        else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)
                        else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)

-                           c2 = PL_fold_locale[c1];
+                           st->u.curlym.c2 = PL_fold_locale[st->u.curlym.c1];

                        else
                        else

-                           c2 = c1;
+                           st->u.curlym.c2 = st->u.curlym.c1;

                    }
                }
                else
                    }
                }
                else

-                   c1 = c2 = -1000;
+                   st->u.curlym.c1 = st->u.curlym.c2 = -1000;

            assume_ok_MM:
            assume_ok_MM:

-               REGCP_SET(lastcp);
-               while (n >= ln || (n == REG_INFTY && ln > 0)) { /* ln overflow ? */
+               REGCP_SET(st->u.curlym.lastcp);
+               while (n >= st->ln || (n == REG_INFTY && st->ln > 0)) { /* ln overflow ? */

                    /* If it could work, try it. */
                    /* If it could work, try it. */

-                   if (c1 == -1000 ||
-                       UCHARAT(PL_reginput) == c1 ||
-                       UCHARAT(PL_reginput) == c2)
+                   if (st->u.curlym.c1 == -1000 ||
+                       UCHARAT(PL_reginput) == st->u.curlym.c1 ||
+                       UCHARAT(PL_reginput) == st->u.curlym.c2)

                    {
                    {

-                       if (paren) {
-                           if (ln) {
-                               PL_regstartp[paren] =
-                                   HOPc(PL_reginput, -l) - PL_bostr;
-                               PL_regendp[paren] = PL_reginput - PL_bostr;
+                       if (st->u.curlym.paren) {
+                           if (st->ln) {
+                               PL_regstartp[st->u.curlym.paren] =
+                                   HOPc(PL_reginput, -st->u.curlym.l) - PL_bostr;
+                               PL_regendp[st->u.curlym.paren] = PL_reginput - PL_bostr;

                            }
                            else
                            }
                            else

-                               PL_regendp[paren] = -1;
+                               PL_regendp[st->u.curlym.paren] = -1;

                        }
                        }

-                       if (regmatch(next))
+                       REGMATCH(next, CURLYM2);
+                       /*** all unsaved local vars undefined at this point */
+                       if (result)

                            sayYES;
                            sayYES;

-                       REGCP_UNWIND(lastcp);
+                       REGCP_UNWIND(st->u.curlym.lastcp);

                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;
                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;

-                   if (regrepeat_hard(scan, 1, &l)) {
-                       ln++;
+                   REGMATCH(scan, CURLYM3);
+                   /*** all unsaved local vars undefined at this point */
+                   if (result) {
+                       st->ln++;

                        locinput = PL_reginput;
                    }
                    else
                        locinput = PL_reginput;
                    }
                    else


@@ -3800,100 +3931,103 @@ S_regmatch(pTHX_ regnode *prog)
                }
            }
            else {
                }
            }
            else {

-               n = regrepeat_hard(scan, n, &l);
-               locinput = PL_reginput;

                DEBUG_EXECUTE_r(
                    PerlIO_printf(Perl_debug_log,
                DEBUG_EXECUTE_r(
                    PerlIO_printf(Perl_debug_log,

-                                 "%*s  matched %"IVdf" times, len=%"IVdf"...\n",
-                                 (int)(REPORT_CODE_OFF+PL_regindent*2), "",
-                                 (IV) n, (IV)l)
+                             "%*s  matched %"IVdf" times, len=%"IVdf"...\n",
+                             (int)(REPORT_CODE_OFF+PL_regindent*2), "",
+                             (IV) st->u.curlym.matches, (IV)st->u.curlym.l)

                    );
                    );

-               if (n >= ln) {
+               if (st->u.curlym.matches >= st->ln) {

                    if (HAS_TEXT(next) || JUMPABLE(next)) {
                        regnode *text_node = next;
 
                        if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
                    if (HAS_TEXT(next) || JUMPABLE(next)) {
                        regnode *text_node = next;
 
                        if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 

-                       if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
+                       if (! HAS_TEXT(text_node)) st->u.curlym.c1 = st->u.curlym.c2 = -1000;

                        else {
                            if (PL_regkind[(U8)OP(text_node)] == REF) {
                        else {
                            if (PL_regkind[(U8)OP(text_node)] == REF) {

-                               c1 = c2 = -1000;
+                               st->u.curlym.c1 = st->u.curlym.c2 = -1000;

                                goto assume_ok_REG;
                            }
                                goto assume_ok_REG;
                            }

-                           else { c1 = (U8)*STRING(text_node); }
+                           else { st->u.curlym.c1 = (U8)*STRING(text_node); }

 
                            if (OP(text_node) == EXACTF || OP(text_node) == REFF)
 
                            if (OP(text_node) == EXACTF || OP(text_node) == REFF)

-                               c2 = PL_fold[c1];
+                               st->u.curlym.c2 = PL_fold[st->u.curlym.c1];

                            else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)
                            else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)

-                               c2 = PL_fold_locale[c1];
+                               st->u.curlym.c2 = PL_fold_locale[st->u.curlym.c1];

                            else
                            else

-                               c2 = c1;
+                               st->u.curlym.c2 = st->u.curlym.c1;

                        }
                    }
                    else
                        }
                    }
                    else

-                       c1 = c2 = -1000;
+                       st->u.curlym.c1 = st->u.curlym.c2 = -1000;

                }
            assume_ok_REG:
                }
            assume_ok_REG:

-               REGCP_SET(lastcp);
-               while (n >= ln) {
+               REGCP_SET(st->u.curlym.lastcp);
+               while (st->u.curlym.matches >= st->ln) {

                    /* If it could work, try it. */
                    /* If it could work, try it. */

-                   if (c1 == -1000 ||
-                       UCHARAT(PL_reginput) == c1 ||
-                       UCHARAT(PL_reginput) == c2)
+                   if (st->u.curlym.c1 == -1000 ||
+                       UCHARAT(PL_reginput) == st->u.curlym.c1 ||
+                       UCHARAT(PL_reginput) == st->u.curlym.c2)

                    {
                        DEBUG_EXECUTE_r(
                    {
                        DEBUG_EXECUTE_r(

-                               PerlIO_printf(Perl_debug_log,
-                                             "%*s  trying tail with n=%"IVdf"...\n",
-                                             (int)(REPORT_CODE_OFF+PL_regindent*2), "", (IV)n)
+                           PerlIO_printf(Perl_debug_log,
+                               "%*s  trying tail with matches=%"IVdf"...\n",
+                               (int)(REPORT_CODE_OFF+PL_regindent*2),
+                               "", (IV)st->u.curlym.matches)

                            );
                            );

-                       if (paren) {
-                           if (n) {
-                               PL_regstartp[paren] = HOPc(PL_reginput, -l) - PL_bostr;
-                               PL_regendp[paren] = PL_reginput - PL_bostr;
+                       if (st->u.curlym.paren) {
+                           if (st->u.curlym.matches) {
+                               PL_regstartp[st->u.curlym.paren]
+                                   = HOPc(PL_reginput, -st->u.curlym.l) - PL_bostr;
+                               PL_regendp[st->u.curlym.paren] = PL_reginput - PL_bostr;

                            }
                            else
                            }
                            else

-                               PL_regendp[paren] = -1;
+                               PL_regendp[st->u.curlym.paren] = -1;

                        }
                        }

-                       if (regmatch(next))
+                       REGMATCH(next, CURLYM4);
+                       /*** all unsaved local vars undefined at this point */
+                       if (result)

                            sayYES;
                            sayYES;

-                       REGCP_UNWIND(lastcp);
+                       REGCP_UNWIND(st->u.curlym.lastcp);

                    }
                    /* Couldn't or didn't -- back up. */
                    }
                    /* Couldn't or didn't -- back up. */

-                   n--;
-                   locinput = HOPc(locinput, -l);
+                   st->u.curlym.matches--;
+                   locinput = HOPc(locinput, -st->u.curlym.l);

                    PL_reginput = locinput;
                }
            }
            sayNO;
                    PL_reginput = locinput;
                }
            }
            sayNO;

+           /* NOTREACHED */

            break;
        }
        case CURLYN:
            break;
        }
        case CURLYN:

-           paren = scan->flags;        /* Which paren to set */
-           if (paren > PL_regsize)
-               PL_regsize = paren;
-           if (paren > (I32)*PL_reglastparen)
-               *PL_reglastparen = paren;
-           ln = ARG1(scan);  /* min to match */
+           st->u.plus.paren = scan->flags;     /* Which paren to set */
+           if (st->u.plus.paren > PL_regsize)
+               PL_regsize = st->u.plus.paren;
+           if (st->u.plus.paren > (I32)*PL_reglastparen)
+               *PL_reglastparen = st->u.plus.paren;
+           st->ln = ARG1(scan);  /* min to match */

            n  = ARG2(scan);  /* max to match */
             scan = regnext(NEXTOPER(scan) + NODE_STEP_REGNODE);
            goto repeat;
        case CURLY:
            n  = ARG2(scan);  /* max to match */
             scan = regnext(NEXTOPER(scan) + NODE_STEP_REGNODE);
            goto repeat;
        case CURLY:

-           paren = 0;
-           ln = ARG1(scan);  /* min to match */
+           st->u.plus.paren = 0;
+           st->ln = ARG1(scan);  /* min to match */

            n  = ARG2(scan);  /* max to match */
            scan = NEXTOPER(scan) + NODE_STEP_REGNODE;
            goto repeat;
        case STAR:
            n  = ARG2(scan);  /* max to match */
            scan = NEXTOPER(scan) + NODE_STEP_REGNODE;
            goto repeat;
        case STAR:

-           ln = 0;
+           st->ln = 0;

            n = REG_INFTY;
            scan = NEXTOPER(scan);
            n = REG_INFTY;
            scan = NEXTOPER(scan);

-           paren = 0;
+           st->u.plus.paren = 0;

            goto repeat;
        case PLUS:
            goto repeat;
        case PLUS:

-           ln = 1;
+           st->ln = 1;

            n = REG_INFTY;
            scan = NEXTOPER(scan);
            n = REG_INFTY;
            scan = NEXTOPER(scan);

-           paren = 0;
+           st->u.plus.paren = 0;

          repeat:
            /*
            * Lookahead to avoid useless match attempts
          repeat:
            /*
            * Lookahead to avoid useless match attempts


@@ -3912,20 +4046,20 @@ S_regmatch(pTHX_ regnode *prog)
 
                if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
 
                if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 

-               if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
+               if (! HAS_TEXT(text_node)) st->u.plus.c1 = st->u.plus.c2 = -1000;

                else {
                    if (PL_regkind[(U8)OP(text_node)] == REF) {
                else {
                    if (PL_regkind[(U8)OP(text_node)] == REF) {

-                       c1 = c2 = -1000;
+                       st->u.plus.c1 = st->u.plus.c2 = -1000;

                        goto assume_ok_easy;
                    }
                    else { s = (U8*)STRING(text_node); }
 
                    if (!UTF) {
                        goto assume_ok_easy;
                    }
                    else { s = (U8*)STRING(text_node); }
 
                    if (!UTF) {

-                       c2 = c1 = *s;
+                       st->u.plus.c2 = st->u.plus.c1 = *s;

                        if (OP(text_node) == EXACTF || OP(text_node) == REFF)
                        if (OP(text_node) == EXACTF || OP(text_node) == REFF)

-                           c2 = PL_fold[c1];
+                           st->u.plus.c2 = PL_fold[st->u.plus.c1];

                        else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)
                        else if (OP(text_node) == EXACTFL || OP(text_node) == REFFL)

-                           c2 = PL_fold_locale[c1];
+                           st->u.plus.c2 = PL_fold_locale[st->u.plus.c1];

                    }
                    else { /* UTF */
                        if (OP(text_node) == EXACTF || OP(text_node) == REFF) {
                    }
                    else { /* UTF */
                        if (OP(text_node) == EXACTF || OP(text_node) == REFF) {


@@ -3936,118 +4070,117 @@ S_regmatch(pTHX_ regnode *prog)
                             to_utf8_lower((U8*)s, tmpbuf1, &ulen1);
                             to_utf8_upper((U8*)s, tmpbuf2, &ulen2);
 
                             to_utf8_lower((U8*)s, tmpbuf1, &ulen1);
                             to_utf8_upper((U8*)s, tmpbuf2, &ulen2);
 

-                            c1 = utf8n_to_uvuni(tmpbuf1, UTF8_MAXBYTES, 0,
+                            st->u.plus.c1 = utf8n_to_uvuni(tmpbuf1, UTF8_MAXBYTES, 0,

                                                 uniflags);
                                                 uniflags);

-                            c2 = utf8n_to_uvuni(tmpbuf2, UTF8_MAXBYTES, 0,
+                            st->u.plus.c2 = utf8n_to_uvuni(tmpbuf2, UTF8_MAXBYTES, 0,

                                                 uniflags);
                        }
                        else {
                                                 uniflags);
                        }
                        else {

-                           c2 = c1 = utf8n_to_uvchr(s, UTF8_MAXBYTES, 0,
+                           st->u.plus.c2 = st->u.plus.c1 = utf8n_to_uvchr(s, UTF8_MAXBYTES, 0,

                                                     uniflags);
                        }
                    }
                }
            }
            else
                                                     uniflags);
                        }
                    }
                }
            }
            else

-               c1 = c2 = -1000;
+               st->u.plus.c1 = st->u.plus.c2 = -1000;

        assume_ok_easy:
            PL_reginput = locinput;
        assume_ok_easy:
            PL_reginput = locinput;

-           if (minmod) {
-               CHECKPOINT lastcp;
-               minmod = 0;
-               if (ln && regrepeat(scan, ln) < ln)
+           if (st->minmod) {
+               st->minmod = 0;
+               if (st->ln && regrepeat(rex, scan, st->ln) < st->ln)

                    sayNO;
                locinput = PL_reginput;
                    sayNO;
                locinput = PL_reginput;

-               REGCP_SET(lastcp);
-               if (c1 != -1000) {
-                   char *e; /* Should not check after this */
-                   char *old = locinput;
-                   int count = 0;
+               REGCP_SET(st->u.plus.lastcp);
+               if (st->u.plus.c1 != -1000) {
+                   st->u.plus.old = locinput;
+                   st->u.plus.count = 0;

 
                    if  (n == REG_INFTY) {
 
                    if  (n == REG_INFTY) {

-                       e = PL_regeol - 1;
+                       st->u.plus.e = PL_regeol - 1;

                        if (do_utf8)
                        if (do_utf8)

-                           while (UTF8_IS_CONTINUATION(*(U8*)e))
-                               e--;
+                           while (UTF8_IS_CONTINUATION(*(U8*)st->u.plus.e))
+                               st->u.plus.e--;

                    }
                    else if (do_utf8) {
                    }
                    else if (do_utf8) {

-                       int m = n - ln;
-                       for (e = locinput;
-                            m >0 && e + UTF8SKIP(e) <= PL_regeol; m--)
-                           e += UTF8SKIP(e);
+                       int m = n - st->ln;
+                       for (st->u.plus.e = locinput;
+                            m >0 && st->u.plus.e + UTF8SKIP(st->u.plus.e) <= PL_regeol; m--)
+                           st->u.plus.e += UTF8SKIP(st->u.plus.e);

                    }
                    else {
                    }
                    else {

-                       e = locinput + n - ln;
-                       if (e >= PL_regeol)
-                           e = PL_regeol - 1;
+                       st->u.plus.e = locinput + n - st->ln;
+                       if (st->u.plus.e >= PL_regeol)
+                           st->u.plus.e = PL_regeol - 1;

                    }
                    while (1) {
                        /* Find place 'next' could work */
                        if (!do_utf8) {
                    }
                    while (1) {
                        /* Find place 'next' could work */
                        if (!do_utf8) {

-                           if (c1 == c2) {
-                               while (locinput <= e &&
-                                      UCHARAT(locinput) != c1)
+                           if (st->u.plus.c1 == st->u.plus.c2) {
+                               while (locinput <= st->u.plus.e &&
+                                      UCHARAT(locinput) != st->u.plus.c1)

                                    locinput++;
                            } else {
                                    locinput++;
                            } else {

-                               while (locinput <= e
-                                      && UCHARAT(locinput) != c1
-                                      && UCHARAT(locinput) != c2)
+                               while (locinput <= st->u.plus.e
+                                      && UCHARAT(locinput) != st->u.plus.c1
+                                      && UCHARAT(locinput) != st->u.plus.c2)

                                    locinput++;
                            }
                                    locinput++;
                            }

-                           count = locinput - old;
+                           st->u.plus.count = locinput - st->u.plus.old;

                        }
                        else {
                        }
                        else {

-                           if (c1 == c2) {
+                           if (st->u.plus.c1 == st->u.plus.c2) {

                                STRLEN len;
                                /* count initialised to
                                 * utf8_distance(old, locinput) */
                                STRLEN len;
                                /* count initialised to
                                 * utf8_distance(old, locinput) */

-                               while (locinput <= e &&
+                               while (locinput <= st->u.plus.e &&

                                       utf8n_to_uvchr((U8*)locinput,
                                                      UTF8_MAXBYTES, &len,
                                       utf8n_to_uvchr((U8*)locinput,
                                                      UTF8_MAXBYTES, &len,

-                                                     uniflags) != (UV)c1) {
+                                                     uniflags) != (UV)st->u.plus.c1) {

                                    locinput += len;
                                    locinput += len;

-                                   count++;
+                                   st->u.plus.count++;

                                }
                            } else {
                                STRLEN len;
                                /* count initialised to
                                 * utf8_distance(old, locinput) */
                                }
                            } else {
                                STRLEN len;
                                /* count initialised to
                                 * utf8_distance(old, locinput) */

-                               while (locinput <= e) {
+                               while (locinput <= st->u.plus.e) {

                                    UV c = utf8n_to_uvchr((U8*)locinput,
                                                          UTF8_MAXBYTES, &len,
                                                          uniflags);
                                    UV c = utf8n_to_uvchr((U8*)locinput,
                                                          UTF8_MAXBYTES, &len,
                                                          uniflags);

-                                   if (c == (UV)c1 || c == (UV)c2)
+                                   if (c == (UV)st->u.plus.c1 || c == (UV)st->u.plus.c2)

                                        break;
                                    locinput += len;
                                        break;
                                    locinput += len;

-                                   count++;
+                                   st->u.plus.count++;

                                }
                            }
                        }
                                }
                            }
                        }

-                       if (locinput > e)
+                       if (locinput > st->u.plus.e)

                            sayNO;
                        /* PL_reginput == old now */
                            sayNO;
                        /* PL_reginput == old now */

-                       if (locinput != old) {
-                           ln = 1;     /* Did some */
-                           if (regrepeat(scan, count) < count)
+                       if (locinput != st->u.plus.old) {
+                           st->ln = 1; /* Did some */
+                           if (regrepeat(rex, scan, st->u.plus.count) < st->u.plus.count)

                                sayNO;
                        }
                        /* PL_reginput == locinput now */
                                sayNO;
                        }
                        /* PL_reginput == locinput now */

-                       TRYPAREN(paren, ln, locinput);
+                       TRYPAREN(st->u.plus.paren, st->ln, locinput, PLUS1);
+                       /*** all unsaved local vars undefined at this point */

                        PL_reginput = locinput; /* Could be reset... */
                        PL_reginput = locinput; /* Could be reset... */

-                       REGCP_UNWIND(lastcp);
+                       REGCP_UNWIND(st->u.plus.lastcp);

                        /* Couldn't or didn't -- move forward. */
                        /* Couldn't or didn't -- move forward. */

-                       old = locinput;
+                       st->u.plus.old = locinput;

                        if (do_utf8)
                            locinput += UTF8SKIP(locinput);
                        else
                            locinput++;
                        if (do_utf8)
                            locinput += UTF8SKIP(locinput);
                        else
                            locinput++;

-                       count = 1;
+                       st->u.plus.count = 1;

                    }
                }
                else
                    }
                }
                else

-               while (n >= ln || (n == REG_INFTY && ln > 0)) { /* ln overflow ? */
+               while (n >= st->ln || (n == REG_INFTY && st->ln > 0)) { /* ln overflow ? */

                    UV c;
                    UV c;

-                   if (c1 != -1000) {
+                   if (st->u.plus.c1 != -1000) {

                        if (do_utf8)
                            c = utf8n_to_uvchr((U8*)PL_reginput,
                                               UTF8_MAXBYTES, 0,
                        if (do_utf8)
                            c = utf8n_to_uvchr((U8*)PL_reginput,
                                               UTF8_MAXBYTES, 0,


@@ -4055,22 +4188,24 @@ S_regmatch(pTHX_ regnode *prog)
                        else
                            c = UCHARAT(PL_reginput);
                        /* If it could work, try it. */
                        else
                            c = UCHARAT(PL_reginput);
                        /* If it could work, try it. */

-                       if (c == (UV)c1 || c == (UV)c2)
+                       if (c == (UV)st->u.plus.c1 || c == (UV)st->u.plus.c2)

                        {
                        {

-                           TRYPAREN(paren, ln, PL_reginput);
-                           REGCP_UNWIND(lastcp);
+                           TRYPAREN(st->u.plus.paren, st->ln, PL_reginput, PLUS2);
+                           /*** all unsaved local vars undefined at this point */
+                           REGCP_UNWIND(st->u.plus.lastcp);

                        }
                    }
                    /* If it could work, try it. */
                        }
                    }
                    /* If it could work, try it. */

-                   else if (c1 == -1000)
+                   else if (st->u.plus.c1 == -1000)

                    {
                    {

-                       TRYPAREN(paren, ln, PL_reginput);
-                       REGCP_UNWIND(lastcp);
+                       TRYPAREN(st->u.plus.paren, st->ln, PL_reginput, PLUS3);
+                       /*** all unsaved local vars undefined at this point */
+                       REGCP_UNWIND(st->u.plus.lastcp);

                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;
                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;

-                   if (regrepeat(scan, 1)) {
-                       ln++;
+                   if (regrepeat(rex, scan, 1)) {
+                       st->ln++;

                        locinput = PL_reginput;
                    }
                    else
                        locinput = PL_reginput;
                    }
                    else


@@ -4078,47 +4213,24 @@ S_regmatch(pTHX_ regnode *prog)
                }
            }
            else {
                }
            }
            else {

-               CHECKPOINT lastcp;
-               n = regrepeat(scan, n);
+               n = regrepeat(rex, scan, n);

                locinput = PL_reginput;
                locinput = PL_reginput;

-               if (ln < n && PL_regkind[(U8)OP(next)] == EOL &&
+               if (st->ln < n && PL_regkind[(U8)OP(next)] == EOL &&

                    (OP(next) != MEOL ||
                        OP(next) == SEOL || OP(next) == EOS))
                {
                    (OP(next) != MEOL ||
                        OP(next) == SEOL || OP(next) == EOS))
                {

-                   ln = n;                     /* why back off? */
+                   st->ln = n;                 /* why back off? */

                    /* ...because $ and \Z can match before *and* after
                       newline at the end.  Consider "\n\n" =~ /\n+\Z\n/.
                       We should back off by one in this case. */
                    if (UCHARAT(PL_reginput - 1) == '\n' && OP(next) != EOS)
                    /* ...because $ and \Z can match before *and* after
                       newline at the end.  Consider "\n\n" =~ /\n+\Z\n/.
                       We should back off by one in this case. */
                    if (UCHARAT(PL_reginput - 1) == '\n' && OP(next) != EOS)

-                       ln--;
+                       st->ln--;

                }
                }

-               REGCP_SET(lastcp);
-               if (paren) {
-                   UV c = 0;
-                   while (n >= ln) {
-                       if (c1 != -1000) {
-                           if (do_utf8)
-                               c = utf8n_to_uvchr((U8*)PL_reginput,
-                                                  UTF8_MAXBYTES, 0,
-                                                  uniflags);
-                           else
-                               c = UCHARAT(PL_reginput);
-                       }
-                       /* If it could work, try it. */
-                       if (c1 == -1000 || c == (UV)c1 || c == (UV)c2)
-                           {
-                               TRYPAREN(paren, n, PL_reginput);
-                               REGCP_UNWIND(lastcp);
-                           }
-                       /* Couldn't or didn't -- back up. */
-                       n--;
-                       PL_reginput = locinput = HOPc(locinput, -1);
-                   }
-               }
-               else {
+               REGCP_SET(st->u.plus.lastcp);
+               {

                    UV c = 0;
                    UV c = 0;

-                   while (n >= ln) {
-                       if (c1 != -1000) {
+                   while (n >= st->ln) {
+                       if (st->u.plus.c1 != -1000) {

                            if (do_utf8)
                                c = utf8n_to_uvchr((U8*)PL_reginput,
                                                   UTF8_MAXBYTES, 0,
                            if (do_utf8)
                                c = utf8n_to_uvchr((U8*)PL_reginput,
                                                   UTF8_MAXBYTES, 0,


@@ -4127,10 +4239,11 @@ S_regmatch(pTHX_ regnode *prog)
                                c = UCHARAT(PL_reginput);
                        }
                        /* If it could work, try it. */
                                c = UCHARAT(PL_reginput);
                        }
                        /* If it could work, try it. */

-                       if (c1 == -1000 || c == (UV)c1 || c == (UV)c2)
+                       if (st->u.plus.c1 == -1000 || c == (UV)st->u.plus.c1 || c == (UV)st->u.plus.c2)

                            {
                            {

-                               TRYPAREN(paren, n, PL_reginput);
-                               REGCP_UNWIND(lastcp);
+                               TRYPAREN(st->u.plus.paren, n, PL_reginput, PLUS4);
+                               /*** all unsaved local vars undefined at this point */
+                               REGCP_UNWIND(st->u.plus.lastcp);

                            }
                        /* Couldn't or didn't -- back up. */
                        n--;
                            }
                        /* Couldn't or didn't -- back up. */
                        n--;


@@ -4141,46 +4254,12 @@ S_regmatch(pTHX_ regnode *prog)
            sayNO;
            break;
        case END:
            sayNO;
            break;
        case END:

-           if (PL_reg_call_cc) {
-               re_cc_state *cur_call_cc = PL_reg_call_cc;
-               CURCUR *cctmp = PL_regcc;
-               regexp *re = PL_reg_re;
-               CHECKPOINT cp, lastcp;
-               
-               cp = regcppush(0);      /* Save *all* the positions. */
-               REGCP_SET(lastcp);
-               regcp_set_to(PL_reg_call_cc->ss); /* Restore parens of
-                                                   the caller. */
-               PL_reginput = locinput; /* Make position available to
-                                          the callcc. */
-               cache_re(PL_reg_call_cc->re);
-               PL_regcc = PL_reg_call_cc->cc;
-               PL_reg_call_cc = PL_reg_call_cc->prev;
-               if (regmatch(cur_call_cc->node)) {
-                   PL_reg_call_cc = cur_call_cc;
-                   regcpblow(cp);
-                   sayYES;
-               }
-               REGCP_UNWIND(lastcp);
-               regcppop();
-               PL_reg_call_cc = cur_call_cc;
-               PL_regcc = cctmp;
-               PL_reg_re = re;
-               cache_re(re);
-
-               DEBUG_EXECUTE_r(
-                   PerlIO_printf(Perl_debug_log,
-                                 "%*s  continuation failed...\n",
-                                 REPORT_CODE_OFF+PL_regindent*2, "")
-                   );
-               sayNO_SILENT;
-           }
-           if (locinput < PL_regtill) {
+           if (locinput < reginfo->till) {

                DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                                      "%sMatch possible, but length=%ld is smaller than requested=%ld, failing!%s\n",
                                      PL_colors[4],
                                      (long)(locinput - PL_reg_starttry),
                DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                                      "%sMatch possible, but length=%ld is smaller than requested=%ld, failing!%s\n",
                                      PL_colors[4],
                                      (long)(locinput - PL_reg_starttry),

-                                     (long)(PL_regtill - PL_reg_starttry),
+                                     (long)(reginfo->till - PL_reg_starttry),

                                      PL_colors[5]));
                sayNO_FINAL;            /* Cannot match: too short. */
            }
                                      PL_colors[5]));
                sayNO_FINAL;            /* Cannot match: too short. */
            }


@@ -4196,7 +4275,7 @@ S_regmatch(pTHX_ regnode *prog)
        case UNLESSM:
            n = 0;
            if (scan->flags) {
        case UNLESSM:
            n = 0;
            if (scan->flags) {

-               s = HOPBACKc(locinput, scan->flags);
+               char * const s = HOPBACKc(locinput, scan->flags);

                if (!s)
                    goto say_yes;
                PL_reginput = s;
                if (!s)
                    goto say_yes;
                PL_reginput = s;


@@ -4207,7 +4286,7 @@ S_regmatch(pTHX_ regnode *prog)
        case IFMATCH:
            n = 1;
            if (scan->flags) {
        case IFMATCH:
            n = 1;
            if (scan->flags) {

-               s = HOPBACKc(locinput, scan->flags);
+               char * const s = HOPBACKc(locinput, scan->flags);

                if (!s)
                    goto say_no;
                PL_reginput = s;
                if (!s)
                    goto say_no;
                PL_reginput = s;


@@ -4216,21 +4295,22 @@ S_regmatch(pTHX_ regnode *prog)
                PL_reginput = locinput;
 
          do_ifmatch:
                PL_reginput = locinput;
 
          do_ifmatch:

-           inner = NEXTOPER(NEXTOPER(scan));
-           if (regmatch(inner) != n) {
+           REGMATCH(NEXTOPER(NEXTOPER(scan)), IFMATCH);
+           /*** all unsaved local vars undefined at this point */
+           if (result != n) {

              say_no:
              say_no:

-               if (logical) {
-                   logical = 0;
-                   sw = 0;
+               if (st->logical) {
+                   st->logical = 0;
+                   st->sw = 0;

                    goto do_longjump;
                }
                else
                    sayNO;
            }
          say_yes:
                    goto do_longjump;
                }
                else
                    sayNO;
            }
          say_yes:

-           if (logical) {
-               logical = 0;
-               sw = 1;
+           if (st->logical) {
+               st->logical = 0;
+               st->sw = 1;

            }
            if (OP(scan) == SUSPEND) {
                locinput = PL_reginput;
            }
            if (OP(scan) == SUSPEND) {
                locinput = PL_reginput;


@@ -4248,10 +4328,49 @@ S_regmatch(pTHX_ regnode *prog)
                          PTR2UV(scan), OP(scan));
            Perl_croak(aTHX_ "regexp memory corruption");
        }
                          PTR2UV(scan), OP(scan));
            Perl_croak(aTHX_ "regexp memory corruption");
        }

+

       reenter:
        scan = next;
       reenter:
        scan = next;

+       continue;
+       /* NOTREACHED */
+
+       /* simulate recursively calling regmatch(), but without actually
+        * recursing - ie save the current state on the heap rather than on
+        * the stack, then re-enter the loop. This avoids complex regexes
+        * blowing the processor stack */
+
+      start_recurse:
+       {
+           /* push new state */
+           regmatch_state *oldst = st;
+
+           depth++;
+
+           /* grab the next free state slot */
+           st++;
+           if (st >  SLAB_LAST(PL_regmatch_slab))
+               st = S_push_slab(aTHX);
+           PL_regmatch_state = st;
+
+           oldst->next = next;
+           oldst->n = n;
+           oldst->locinput = locinput;
+
+           st->cc = oldst->cc;
+           locinput = PL_reginput;
+           nextchr = UCHARAT(locinput);
+           st->minmod = 0;
+           st->sw = 0;
+           st->logical = 0;
+           st->unwind = 0;
+#ifdef DEBUGGING
+           PL_regindent++;
+#endif
+       }

     }
 
     }
 

+
+

     /*
     * We get here only if there's trouble -- normally "case END" is
     * the terminating point.
     /*
     * We get here only if there's trouble -- normally "case END" is
     * the terminating point.


@@ -4268,6 +4387,52 @@ yes_loud:
        );
     goto yes;
 yes_final:
        );
     goto yes;
 yes_final:

+
+    if (yes_state) {
+       /* we have successfully completed a subexpression, but we must now
+        * pop to the state marked by yes_state and continue from there */
+
+       assert(st != yes_state);
+       while (yes_state < SLAB_FIRST(PL_regmatch_slab)
+           || yes_state > SLAB_LAST(PL_regmatch_slab))
+       {
+           /* not in this slab, pop slab */
+           depth -= (st - SLAB_FIRST(PL_regmatch_slab) + 1);
+           PL_regmatch_slab = PL_regmatch_slab->prev;
+           st = SLAB_LAST(PL_regmatch_slab);
+       }
+       depth -= (st - yes_state);
+       DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "POP STATE TO (%d)\n", depth)); \
+       st = yes_state;
+       yes_state = st->u.yes.prev_yes_state;
+       PL_regmatch_state = st;
+
+       switch (st->resume_state) {
+       case resume_EVAL:
+           if (st->u.eval.toggleutf)
+               PL_reg_flags ^= RF_utf8;
+           ReREFCNT_dec(rex);
+           rex = st->u.eval.prev_rex;
+           /* XXXX This is too dramatic a measure... */
+           PL_reg_maxiter = 0;
+           /* Restore parens of the caller without popping the
+            * savestack */
+           {
+               I32 tmp = PL_savestack_ix;
+               PL_savestack_ix = st->u.eval.lastcp;
+               regcppop(rex);
+               PL_savestack_ix = tmp;
+           }
+           PL_reginput = locinput;
+            /* continue at the node following the (??{...}) */
+           next        = st->next;
+           goto reenter;
+
+       default:
+           Perl_croak(aTHX_ "unexpected yes reume state");
+       }
+    }
+

     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch successful!%s\n",
                          PL_colors[4], PL_colors[5]));
 yes:
     DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch successful!%s\n",
                          PL_colors[4], PL_colors[5]));
 yes:


@@ -4275,11 +4440,58 @@ yes:
     PL_regindent--;
 #endif
 
     PL_regindent--;
 #endif
 

-#if 0                                  /* Breaks $^R */
-    if (unwind)
-       regcpblow(firstcp);
-#endif
-    return 1;
+    result = 1;
+    /* XXX this is duplicate(ish) code to that in the do_no section.
+     * eventually a yes should just pop the stack back to the current
+     * yes_state */
+    if (depth) {
+       /* restore previous state and re-enter */
+       POP_STATE;
+
+       switch (st->resume_state) {
+       case resume_TRIE1:
+           goto resume_point_TRIE1;
+       case resume_TRIE2:
+           goto resume_point_TRIE2;
+       case resume_CURLYX:
+           goto resume_point_CURLYX;
+       case resume_WHILEM1:
+           goto resume_point_WHILEM1;
+       case resume_WHILEM2:
+           goto resume_point_WHILEM2;
+       case resume_WHILEM3:
+           goto resume_point_WHILEM3;
+       case resume_WHILEM4:
+           goto resume_point_WHILEM4;
+       case resume_WHILEM5:
+           goto resume_point_WHILEM5;
+       case resume_WHILEM6:
+           goto resume_point_WHILEM6;
+       case resume_CURLYM1:
+           goto resume_point_CURLYM1;
+       case resume_CURLYM2:
+           goto resume_point_CURLYM2;
+       case resume_CURLYM3:
+           goto resume_point_CURLYM3;
+       case resume_CURLYM4:
+           goto resume_point_CURLYM4;
+       case resume_IFMATCH:
+           goto resume_point_IFMATCH;
+       case resume_PLUS1:
+           goto resume_point_PLUS1;
+       case resume_PLUS2:
+           goto resume_point_PLUS2;
+       case resume_PLUS3:
+           goto resume_point_PLUS3;
+       case resume_PLUS4:
+           goto resume_point_PLUS4;
+
+       case resume_EVAL:
+       default:
+           Perl_croak(aTHX_ "regexp resume memory corruption");
+       }
+    }
+    goto final_exit;

 
 no:
     DEBUG_EXECUTE_r(
 
 no:
     DEBUG_EXECUTE_r(


@@ -4290,14 +4502,14 @@ no:
     goto do_no;
 no_final:
 do_no:
     goto do_no;
 no_final:
 do_no:

-    if (unwind) {
-       re_unwind_t *uw = SSPTRt(unwind,re_unwind_t);
+    if (st->unwind) {
+       re_unwind_t * const uw = SSPTRt(st->unwind,re_unwind_t);

 
        switch (uw->type) {
        case RE_UNWIND_BRANCH:
        case RE_UNWIND_BRANCHJ:
        {
 
        switch (uw->type) {
        case RE_UNWIND_BRANCH:
        case RE_UNWIND_BRANCHJ:
        {

-           re_unwind_branch_t *uwb = &(uw->branch);
+           re_unwind_branch_t * const uwb = &(uw->branch);

            const I32 lastparen = uwb->lastparen;
        
            REGCP_UNWIND(uwb->lastcp);
            const I32 lastparen = uwb->lastparen;
        
            REGCP_UNWIND(uwb->lastcp);


@@ -4305,10 +4517,11 @@ do_no:
                PL_regendp[n] = -1;
            *PL_reglastparen = n;
            scan = next = uwb->next;
                PL_regendp[n] = -1;
            *PL_reglastparen = n;
            scan = next = uwb->next;

+           st->minmod = uwb->minmod;

            if ( !scan ||
                 OP(scan) != (uwb->type == RE_UNWIND_BRANCH
                              ? BRANCH : BRANCHJ) ) {           /* Failure */
            if ( !scan ||
                 OP(scan) != (uwb->type == RE_UNWIND_BRANCH
                              ? BRANCH : BRANCHJ) ) {           /* Failure */

-               unwind = uwb->prev;
+               st->unwind = uwb->prev;

 #ifdef DEBUGGING
                PL_regindent--;
 #endif
 #ifdef DEBUGGING
                PL_regindent--;
 #endif


@@ -4332,16 +4545,99 @@ do_no:
 
            goto reenter;
        }
 
            goto reenter;
        }

-       /* NOT REACHED */
+       /* NOTREACHED */

        default:
            Perl_croak(aTHX_ "regexp unwind memory corruption");
        }
        default:
            Perl_croak(aTHX_ "regexp unwind memory corruption");
        }

-       /* NOT REACHED */
+       /* NOTREACHED */

     }
     }

+

 #ifdef DEBUGGING
     PL_regindent--;
 #endif
 #ifdef DEBUGGING
     PL_regindent--;
 #endif

-    return 0;
+    result = 0;
+
+    if (depth) {
+       /* there's a previous state to backtrack to */
+       POP_STATE;
+       switch (st->resume_state) {
+       case resume_TRIE1:
+           goto resume_point_TRIE1;
+       case resume_TRIE2:
+           goto resume_point_TRIE2;
+       case resume_EVAL:
+           /* we have failed an (??{...}). Restore state to the outer re
+            * then re-throw the failure */
+           if (st->u.eval.toggleutf)
+               PL_reg_flags ^= RF_utf8;
+           ReREFCNT_dec(rex);
+           rex = st->u.eval.prev_rex;
+           yes_state = st->u.yes.prev_yes_state;
+
+           /* XXXX This is too dramatic a measure... */
+           PL_reg_maxiter = 0;
+
+           PL_reginput = locinput;
+           REGCP_UNWIND(st->u.eval.lastcp);
+           regcppop(rex);
+           goto do_no;
+
+       case resume_CURLYX:
+           goto resume_point_CURLYX;
+       case resume_WHILEM1:
+           goto resume_point_WHILEM1;
+       case resume_WHILEM2:
+           goto resume_point_WHILEM2;
+       case resume_WHILEM3:
+           goto resume_point_WHILEM3;
+       case resume_WHILEM4:
+           goto resume_point_WHILEM4;
+       case resume_WHILEM5:
+           goto resume_point_WHILEM5;
+       case resume_WHILEM6:
+           goto resume_point_WHILEM6;
+       case resume_CURLYM1:
+           goto resume_point_CURLYM1;
+       case resume_CURLYM2:
+           goto resume_point_CURLYM2;
+       case resume_CURLYM3:
+           goto resume_point_CURLYM3;
+       case resume_CURLYM4:
+           goto resume_point_CURLYM4;
+       case resume_IFMATCH:
+           goto resume_point_IFMATCH;
+       case resume_PLUS1:
+           goto resume_point_PLUS1;
+       case resume_PLUS2:
+           goto resume_point_PLUS2;
+       case resume_PLUS3:
+           goto resume_point_PLUS3;
+       case resume_PLUS4:
+           goto resume_point_PLUS4;
+       default:
+           Perl_croak(aTHX_ "regexp resume memory corruption");
+       }
+    }
+
+final_exit:
+
+    /* restore original high-water mark */
+    PL_regmatch_slab  = orig_slab;
+    PL_regmatch_state = orig_state;
+
+    /* free all slabs above current one */
+    if (orig_slab->next) {
+       regmatch_slab *osl, *sl = orig_slab->next;
+       orig_slab->next = NULL;
+       while (sl) {
+           osl = sl;
+           sl = sl->next;
+           Safefree(osl);
+       }
+    }
+
+    return result;
+

 }
 
 /*
 }
 
 /*


@@ -4353,7 +4649,7 @@ do_no:
  * rather than incrementing count on every character.  [Er, except utf8.]]
  */
 STATIC I32
  * rather than incrementing count on every character.  [Er, except utf8.]]
  */
 STATIC I32

-S_regrepeat(pTHX_ const regnode *p, I32 max)
+S_regrepeat(pTHX_ const regexp *prog, const regnode *p, I32 max)

 {
     dVAR;
     register char *scan;
 {
     dVAR;
     register char *scan;


@@ -4366,7 +4662,7 @@ S_regrepeat(pTHX_ const regnode *p, I32 max)
     if (max == REG_INFTY)
        max = I32_MAX;
     else if (max < loceol - scan)
     if (max == REG_INFTY)
        max = I32_MAX;
     else if (max < loceol - scan)

-      loceol = scan + max;
+       loceol = scan + max;

     switch (OP(p)) {
     case REG_ANY:
        if (do_utf8) {
     switch (OP(p)) {
     case REG_ANY:
        if (do_utf8) {


@@ -4416,12 +4712,12 @@ S_regrepeat(pTHX_ const regnode *p, I32 max)
        if (do_utf8) {
            loceol = PL_regeol;
            while (hardcount < max && scan < loceol &&
        if (do_utf8) {
            loceol = PL_regeol;
            while (hardcount < max && scan < loceol &&

-                  reginclass(p, (U8*)scan, 0, do_utf8)) {
+                  reginclass(prog, p, (U8*)scan, 0, do_utf8)) {

                scan += UTF8SKIP(scan);
                hardcount++;
            }
        } else {
                scan += UTF8SKIP(scan);
                hardcount++;
            }
        } else {

-           while (scan < loceol && REGINCLASS(p, (U8*)scan))
+           while (scan < loceol && REGINCLASS(prog, p, (U8*)scan))

                scan++;
        }
        break;
                scan++;
        }
        break;


@@ -4579,10 +4875,10 @@ S_regrepeat(pTHX_ const regnode *p, I32 max)
 
     DEBUG_r({
                SV *re_debug_flags = NULL;
 
     DEBUG_r({
                SV *re_debug_flags = NULL;

-               SV *prop = sv_newmortal();
+               SV * const prop = sv_newmortal();

                 GET_RE_DEBUG_FLAGS;
                 DEBUG_EXECUTE_r({
                 GET_RE_DEBUG_FLAGS;
                 DEBUG_EXECUTE_r({

-               regprop(prop, p);
+               regprop(prog, prop, p);

                PerlIO_printf(Perl_debug_log,
                              "%*s  %s can match %"IVdf" times out of %"IVdf"...\n",
                              REPORT_CODE_OFF+1, "", SvPVX_const(prop),(IV)c,(IV)max);
                PerlIO_printf(Perl_debug_log,
                              "%*s  %s can match %"IVdf" times out of %"IVdf"...\n",
                              REPORT_CODE_OFF+1, "", SvPVX_const(prop),(IV)c,(IV)max);


@@ -4592,74 +4888,25 @@ S_regrepeat(pTHX_ const regnode *p, I32 max)
     return(c);
 }
 
     return(c);
 }
 

-/*
- - regrepeat_hard - repeatedly match something, report total lenth and length
- *
- * The repeater is supposed to have constant non-zero length.
- */
-
-STATIC I32
-S_regrepeat_hard(pTHX_ regnode *p, I32 max, I32 *lp)
-{
-    register char *scan = Nullch;
-    register char *start;
-    register char *loceol = PL_regeol;
-    I32 l = 0;
-    I32 count = 0, res = 1;
-
-    if (!max)
-       return 0;
-
-    start = PL_reginput;
-    if (PL_reg_match_utf8) {
-       while (PL_reginput < loceol && (scan = PL_reginput, res = regmatch(p))) {
-           if (!count++) {
-               l = 0;
-               while (start < PL_reginput) {
-                   l++;
-                   start += UTF8SKIP(start);
-               }
-               *lp = l;
-               if (l == 0)
-                   return max;
-           }
-           if (count == max)
-               return count;
-       }
-    }
-    else {
-       while (PL_reginput < loceol && (scan = PL_reginput, res = regmatch(p))) {
-           if (!count++) {
-               *lp = l = PL_reginput - start;
-               if (max != REG_INFTY && l*max < loceol - scan)
-                   loceol = scan + l*max;
-               if (l == 0)
-                   return max;
-           }
-       }
-    }
-    if (!res)
-       PL_reginput = scan;
-
-    return count;
-}

 
 /*
 - regclass_swash - prepare the utf8 swash
 */
 
 SV *
 
 /*
 - regclass_swash - prepare the utf8 swash
 */
 
 SV *

-Perl_regclass_swash(pTHX_ register const regnode* node, bool doinit, SV** listsvp, SV **altsvp)
+Perl_regclass_swash(pTHX_ const regexp *prog, register const regnode* node, bool doinit, SV** listsvp, SV **altsvp)

 {
 {

+    dVAR;

     SV *sw  = NULL;
     SV *si  = NULL;
     SV *alt = NULL;
     SV *sw  = NULL;
     SV *si  = NULL;
     SV *alt = NULL;

+    const struct reg_data *data = prog ? prog->data : NULL;

 
 

-    if (PL_regdata && PL_regdata->count) {
+    if (data && data->count) {

        const U32 n = ARG(node);
 
        const U32 n = ARG(node);
 

-       if (PL_regdata->what[n] == 's') {
-           SV * const rv = (SV*)PL_regdata->data[n];
+       if (data->what[n] == 's') {
+           SV * const rv = (SV*)data->data[n];

            AV * const av = (AV*)SvRV((SV*)rv);
            SV **const ary = AvARRAY(av);
            SV **a, **b;
            AV * const av = (AV*)SvRV((SV*)rv);
            SV **const ary = AvARRAY(av);
            SV **a, **b;


@@ -4701,7 +4948,7 @@ Perl_regclass_swash(pTHX_ register const regnode* node, bool doinit, SV** listsv
  */
 
 STATIC bool
  */
 
 STATIC bool

-S_reginclass(pTHX_ register const regnode *n, register const U8* p, STRLEN* lenp, register bool do_utf8)
+S_reginclass(pTHX_ const regexp *prog, register const regnode *n, register const U8* p, STRLEN* lenp, register bool do_utf8)

 {
     dVAR;
     const char flags = ANYOF_FLAGS(n);
 {
     dVAR;
     const char flags = ANYOF_FLAGS(n);


@@ -4712,8 +4959,8 @@ S_reginclass(pTHX_ register const regnode *n, register const U8* p, STRLEN* lenp
 
     if (do_utf8 && !UTF8_IS_INVARIANT(c)) {
        c = utf8n_to_uvchr(p, UTF8_MAXBYTES, &len,
 
     if (do_utf8 && !UTF8_IS_INVARIANT(c)) {
        c = utf8n_to_uvchr(p, UTF8_MAXBYTES, &len,

-                           ckWARN(WARN_UTF8) ? UTF8_CHECK_ONLY :
-                                       UTF8_ALLOW_ANYUV|UTF8_CHECK_ONLY);
+               (UTF8_ALLOW_DEFAULT & UTF8_ALLOW_ANYUV) | UTF8_CHECK_ONLY);
+               /* see [perl #37836] for UTF8_ALLOW_ANYUV */

        if (len == (STRLEN)-1)
            Perl_croak(aTHX_ "Malformed UTF-8 character (fatal)");
     }
        if (len == (STRLEN)-1)
            Perl_croak(aTHX_ "Malformed UTF-8 character (fatal)");
     }


@@ -4730,7 +4977,7 @@ S_reginclass(pTHX_ register const regnode *n, register const U8* p, STRLEN* lenp
            match = TRUE;
        if (!match) {
            AV *av;
            match = TRUE;
        if (!match) {
            AV *av;

-           SV * const sw = regclass_swash(n, TRUE, 0, (SV**)&av);
+           SV * const sw = regclass_swash(prog, n, TRUE, 0, (SV**)&av);

        
            if (sw) {
                if (swash_fetch(sw, p, do_utf8))
        
            if (sw) {
                if (swash_fetch(sw, p, do_utf8))


@@ -4824,14 +5071,9 @@ S_reginclass(pTHX_ register const regnode *n, register const U8* p, STRLEN* lenp
 }
 
 STATIC U8 *
 }
 
 STATIC U8 *

-S_reghop(pTHX_ U8 *s, I32 off)
-{
-    return S_reghop3(aTHX_ s, off, (U8*)(off >= 0 ? PL_regeol : PL_bostr));
-}
-
-STATIC U8 *
-S_reghop3(pTHX_ U8 *s, I32 off, U8* lim)
+S_reghop3(U8 *s, I32 off, U8* lim)

 {
 {

+    dVAR;

     if (off >= 0) {
        while (off-- && s < lim) {
            /* XXX could check well-formedness here */
     if (off >= 0) {
        while (off-- && s < lim) {
            /* XXX could check well-formedness here */


@@ -4854,14 +5096,9 @@ S_reghop3(pTHX_ U8 *s, I32 off, U8* lim)
 }
 
 STATIC U8 *
 }
 
 STATIC U8 *

-S_reghopmaybe(pTHX_ U8 *s, I32 off)
-{
-    return S_reghopmaybe3(aTHX_ s, off, (U8*)(off >= 0 ? PL_regeol : PL_bostr));
-}
-
-STATIC U8 *
-S_reghopmaybe3(pTHX_ U8* s, I32 off, U8* lim)
+S_reghopmaybe3(U8* s, I32 off, U8* lim)

 {
 {

+    dVAR;

     if (off >= 0) {
        while (off-- && s < lim) {
            /* XXX could check well-formedness here */
     if (off >= 0) {
        while (off-- && s < lim) {
            /* XXX could check well-formedness here */


@@ -4892,15 +5129,16 @@ S_reghopmaybe3(pTHX_ U8* s, I32 off, U8* lim)
 static void
 restore_pos(pTHX_ void *arg)
 {
 static void
 restore_pos(pTHX_ void *arg)
 {

-    PERL_UNUSED_ARG(arg);
+    dVAR;
+    regexp * const rex = (regexp *)arg;

     if (PL_reg_eval_set) {
        if (PL_reg_oldsaved) {
     if (PL_reg_eval_set) {
        if (PL_reg_oldsaved) {

-           PL_reg_re->subbeg = PL_reg_oldsaved;
-           PL_reg_re->sublen = PL_reg_oldsavedlen;
+           rex->subbeg = PL_reg_oldsaved;
+           rex->sublen = PL_reg_oldsavedlen;

 #ifdef PERL_OLD_COPY_ON_WRITE
 #ifdef PERL_OLD_COPY_ON_WRITE

-           PL_reg_re->saved_copy = PL_nrs;
+           rex->saved_copy = PL_nrs;

 #endif
 #endif

-           RX_MATCH_COPIED_on(PL_reg_re);
+           RX_MATCH_COPIED_on(rex);

        }
        PL_reg_magic->mg_len = PL_reg_oldpos;
        PL_reg_eval_set = 0;
        }
        PL_reg_magic->mg_len = PL_reg_oldpos;
        PL_reg_eval_set = 0;


@@ -4912,8 +5150,8 @@ STATIC void
 S_to_utf8_substr(pTHX_ register regexp *prog)
 {
     if (prog->float_substr && !prog->float_utf8) {
 S_to_utf8_substr(pTHX_ register regexp *prog)
 {
     if (prog->float_substr && !prog->float_utf8) {

-       SV* sv;
-       prog->float_utf8 = sv = newSVsv(prog->float_substr);
+       SV* const sv = newSVsv(prog->float_substr);
+       prog->float_utf8 = sv;

        sv_utf8_upgrade(sv);
        if (SvTAIL(prog->float_substr))
            SvTAIL_on(sv);
        sv_utf8_upgrade(sv);
        if (SvTAIL(prog->float_substr))
            SvTAIL_on(sv);


@@ -4921,8 +5159,8 @@ S_to_utf8_substr(pTHX_ register regexp *prog)
            prog->check_utf8 = sv;
     }
     if (prog->anchored_substr && !prog->anchored_utf8) {
            prog->check_utf8 = sv;
     }
     if (prog->anchored_substr && !prog->anchored_utf8) {

-       SV* sv;
-       prog->anchored_utf8 = sv = newSVsv(prog->anchored_substr);
+       SV* const sv = newSVsv(prog->anchored_substr);
+       prog->anchored_utf8 = sv;

        sv_utf8_upgrade(sv);
        if (SvTAIL(prog->anchored_substr))
            SvTAIL_on(sv);
        sv_utf8_upgrade(sv);
        if (SvTAIL(prog->anchored_substr))
            SvTAIL_on(sv);


@@ -4934,9 +5172,10 @@ S_to_utf8_substr(pTHX_ register regexp *prog)
 STATIC void
 S_to_byte_substr(pTHX_ register regexp *prog)
 {
 STATIC void
 S_to_byte_substr(pTHX_ register regexp *prog)
 {

+    dVAR;

     if (prog->float_utf8 && !prog->float_substr) {
     if (prog->float_utf8 && !prog->float_substr) {

-       SV* sv;
-       prog->float_substr = sv = newSVsv(prog->float_utf8);
+       SV* sv = newSVsv(prog->float_utf8);
+       prog->float_substr = sv;

        if (sv_utf8_downgrade(sv, TRUE)) {
            if (SvTAIL(prog->float_utf8))
                SvTAIL_on(sv);
        if (sv_utf8_downgrade(sv, TRUE)) {
            if (SvTAIL(prog->float_utf8))
                SvTAIL_on(sv);


@@ -4948,8 +5187,8 @@ S_to_byte_substr(pTHX_ register regexp *prog)
            prog->check_substr = sv;
     }
     if (prog->anchored_utf8 && !prog->anchored_substr) {
            prog->check_substr = sv;
     }
     if (prog->anchored_utf8 && !prog->anchored_substr) {

-       SV* sv;
-       prog->anchored_substr = sv = newSVsv(prog->anchored_utf8);
+       SV* sv = newSVsv(prog->anchored_utf8);
+       prog->anchored_substr = sv;

        if (sv_utf8_downgrade(sv, TRUE)) {
            if (SvTAIL(prog->anchored_utf8))
                SvTAIL_on(sv);
        if (sv_utf8_downgrade(sv, TRUE)) {
            if (SvTAIL(prog->anchored_utf8))
                SvTAIL_on(sv);