Tweak for MULTIPLICITY/USE_PERLIO
[p5sagit/p5-mst-13.2.git] / regexec.c
index 611b132..be683a3 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -39,6 +39,7 @@
 /* *These* symbols are masked to allow static link. */
 #  define Perl_pregexec my_pregexec
 #  define Perl_reginitcolors my_reginitcolors 
+#  define Perl_regclass_swash my_regclass_swash
 
 #  define PERL_NO_GET_CONTEXT
 #endif 
@@ -66,7 +67,7 @@
  *
  ****    Alterations to Henry's code are...
  ****
- ****    Copyright (c) 1991-1999, Larry Wall
+ ****    Copyright (c) 1991-2000, Larry Wall
  ****
  ****    You may distribute under the terms of either the GNU General Public
  ****    License or the Artistic License, as specified in the README file.
  * Forwards.
  */
 
-#define REGINCLASS(p,c)  (ANYOF_FLAGS(p) ? reginclass(p,c) : ANYOF_BITMAP_TEST(p,c))
-#define REGINCLASSUTF8(f,p)  (ARG1(f) ? reginclassutf8(f,p) : swash_fetch((SV*)PL_regdata->data[ARG2(f)],p))
-
 #define CHR_SVLEN(sv) (UTF ? sv_len_utf8(sv) : SvCUR(sv))
-#define CHR_DIST(a,b) (UTF ? utf8_distance(a,b) : a - b)
+#define CHR_DIST(a,b) (DO_UTF8(PL_reg_sv) ? 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) (UTF ? reghop((U8*)pos, off) : (U8*)(pos + off))
-#define HOPMAYBE(pos,off) (UTF ? reghopmaybe((U8*)pos, off) : (U8*)(pos + off))
+#define HOP(pos,off) (DO_UTF8(PL_reg_sv) ? reghop((U8*)pos, off) : (U8*)(pos + off))
+#define HOPMAYBE(pos,off) (DO_UTF8(PL_reg_sv) ? reghopmaybe((U8*)pos, off) : (U8*)(pos + off))
 #define HOPc(pos,off) ((char*)HOP(pos,off))
 #define HOPMAYBEc(pos,off) ((char*)HOPMAYBE(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) (DO_UTF8(PL_reg_sv) ? reghop3((U8*)pos, off, (U8*)lim) : (U8*)(pos + off))
+#define HOPMAYBE3(pos,off,lim) (DO_UTF8(PL_reg_sv) ? reghopmaybe3((U8*)pos, off, (U8*)lim) : (U8*)(pos + off))
+#define HOP3c(pos,off,lim) ((char*)HOP3(pos,off,lim))
+#define HOPMAYBE3c(pos,off,lim) ((char*)HOPMAYBE3(pos,off,lim))
+
 static void restore_pos(pTHXo_ void *arg);
 
 
 STATIC CHECKPOINT
 S_regcppush(pTHX_ I32 parenfloor)
 {
-    dTHR;
     int retval = PL_savestack_ix;
     int i = (PL_regsize - parenfloor) * 4;
     int p;
@@ -145,19 +149,18 @@ S_regcppush(pTHX_ I32 parenfloor)
 }
 
 /* These are needed since we do not localize EVAL nodes: */
-#  define REGCP_SET  DEBUG_r(PerlIO_printf(Perl_debug_log,             \
-                            "  Setting an EVAL scope, savestack=%i\n", \
-                            PL_savestack_ix)); lastcp = PL_savestack_ix
+#  define REGCP_SET(cp)  DEBUG_r(PerlIO_printf(Perl_debug_log,         \
+                            "  Setting an EVAL scope, savestack=%"IVdf"\n",    \
+                            (IV)PL_savestack_ix)); cp = PL_savestack_ix
 
-#  define REGCP_UNWIND  DEBUG_r(lastcp != PL_savestack_ix ?            \
+#  define REGCP_UNWIND(cp)  DEBUG_r(cp != PL_savestack_ix ?            \
                                PerlIO_printf(Perl_debug_log,           \
-                               "  Clearing an EVAL scope, savestack=%i..%i\n", \
-                               lastcp, PL_savestack_ix) : 0); regcpblow(lastcp)
+                               "  Clearing an EVAL scope, savestack=%"IVdf"..%"IVdf"\n", \
+                               (IV)(cp), (IV)PL_savestack_ix) : 0); regcpblow(cp)
 
 STATIC char *
 S_regcppop(pTHX)
 {
-    dTHR;
     I32 i = SSPOPINT;
     U32 paren = 0;
     char *input;
@@ -186,22 +189,33 @@ S_regcppop(pTHX)
     DEBUG_r(
        if (*PL_reglastparen + 1 <= PL_regnpar) {
            PerlIO_printf(Perl_debug_log,
-                         "     restoring \\%d..\\%d to undef\n",
-                         *PL_reglastparen + 1, PL_regnpar);
+                         "     restoring \\%"IVdf"..\\%"IVdf" to undef\n",
+                         (IV)(*PL_reglastparen + 1), (IV)PL_regnpar);
        }
     );
+#if 1
+    /* It would seem that the similar code in regtry()
+     * already takes care of this, and in fact it is in
+     * a better location to since this code can #if 0-ed out
+     * but the code in regtry() is needed or otherwise tests
+     * requiring null fields (pat.t#187 and split.t#{13,14}
+     * (as of patchlevel 7877)  will fail.  Then again,
+     * this code seems to be necessary or otherwise
+     * building DynaLoader will fail:
+     * "Error: '*' not in typemap in DynaLoader.xs, line 164"
+     * --jhi */
     for (paren = *PL_reglastparen + 1; paren <= PL_regnpar; paren++) {
        if (paren > PL_regsize)
            PL_regstartp[paren] = -1;
        PL_regendp[paren] = -1;
     }
+#endif
     return input;
 }
 
 STATIC char *
 S_regcp_set_to(pTHX_ I32 ss)
 {
-    dTHR;
     I32 tmp = PL_savestack_ix;
 
     PL_savestack_ix = ss;
@@ -219,7 +233,23 @@ typedef struct re_cc_state
     regexp *re;
 } re_cc_state;
 
-#define regcpblow(cp) LEAVE_SCOPE(cp)
+#define regcpblow(cp) LEAVE_SCOPE(cp)  /* Ignores regcppush()ed data. */
+
+#define TRYPAREN(paren, n, input) {                            \
+    if (paren) {                                               \
+       if (n) {                                                \
+           PL_regstartp[paren] = HOPc(input, -1) - PL_bostr;   \
+           PL_regendp[paren] = input - PL_bostr;               \
+       }                                                       \
+       else                                                    \
+           PL_regendp[paren] = -1;                             \
+    }                                                          \
+    if (regmatch(next))                                                \
+       sayYES;                                                 \
+    if (paren && n)                                            \
+       PL_regendp[paren] = -1;                                 \
+}
+
 
 /*
  * pregexec and friends
@@ -244,7 +274,6 @@ Perl_pregexec(pTHX_ register regexp *prog, char *stringarg, register char *stren
 STATIC void
 S_cache_re(pTHX_ regexp *prog)
 {
-    dTHR;
     PL_regprecomp = prog->precomp;             /* Needed for FAIL. */
 #ifdef DEBUGGING
     PL_regprogram = prog->program;
@@ -275,6 +304,13 @@ S_cache_re(pTHX_ regexp *prog)
 
 /* XXXX We assume that strpos is strbeg unless sv. */
 
+/* XXXX Some places assume that there is a fixed substring.
+       An update may be needed if optimizer marks as "INTUITable"
+       RExen without fixed substrings.  Similarly, it is assumed that
+       lengths of all the strings are no more than minlen, thus they
+       cannot come from lookahead.
+       (Or minlen should take into account lookahead.) */
+
 /* A failure to find a constant substring means that there is no need to make
    an expensive call to REx engine, thus we celebrate a failure.  Similarly,
    finding a substring too deep into the string means that less calls to
@@ -285,10 +321,14 @@ S_cache_re(pTHX_ regexp *prog)
        b) Fixed substring;
        c) Whether we are anchored (beginning-of-line or \G);
        d) First node (of those at offset 0) which may distingush positions;
-   We use 'a', 'b', multiline-part of 'c', and try to find a position in the
+   We use a)b)d) and multiline-part of c), and try to find a position in the
    string which does not contradict any of them.
  */
 
+/* Most of decisions we do here should have been done at compile time.
+   The nodes of the REx which we used for the search should have been
+   deleted from the finite automaton. */
+
 char *
 Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                     char *strend, U32 flags, re_scream_pos_data *data)
@@ -298,10 +338,12 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     register I32 end_shift;
     register char *s;
     register SV *check;
+    char *strbeg;
     char *t;
     I32 ml_anch;
     char *tmp;
-    register char *other_last = Nullch;
+    register char *other_last = Nullch;        /* other substr checked before this */
+    char *check_at;                    /* check substr found at this pos */
 #ifdef DEBUGGING
     char *i_strpos = strpos;
 #endif
@@ -319,28 +361,36 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                      (strend - strpos > 60 ? "..." : ""))
        );
 
-    if (prog->minlen > strend - strpos) {
+    if (prog->reganch & ROPT_UTF8)
+       PL_reg_flags |= RF_utf8;
+
+    if (prog->minlen > CHR_DIST((U8*)strend, (U8*)strpos)) {
        DEBUG_r(PerlIO_printf(Perl_debug_log, "String too short...\n"));
        goto fail;
     }
+    strbeg = (sv && SvPOK(sv)) ? strend - SvCUR(sv) : strpos;
+    PL_regeol = strend;
+    check = prog->check_substr;
     if (prog->reganch & ROPT_ANCH) {   /* Match at beg-of-str or after \n */
        ml_anch = !( (prog->reganch & ROPT_ANCH_SINGLE)
                     || ( (prog->reganch & ROPT_ANCH_BOL)
                          && !PL_multiline ) ); /* Check after \n? */
 
-       if ((prog->check_offset_min == prog->check_offset_max) && !ml_anch) {
+       if (!ml_anch) {
+         if ( !(prog->reganch & ROPT_ANCH_GPOS) /* Checked by the caller */
+              /* SvCUR is not set on references: SvRV and SvPVX overlap */
+              && sv && !SvROK(sv)
+              && (strpos != strbeg)) {
+             DEBUG_r(PerlIO_printf(Perl_debug_log, "Not at start...\n"));
+             goto fail;
+         }
+         if (prog->check_offset_min == prog->check_offset_max) {
            /* Substring at constant offset from beg-of-str... */
            I32 slen;
 
-           if ( !(prog->reganch & ROPT_ANCH_GPOS) /* Checked by the caller */
-                && (sv && (strpos + SvCUR(sv) != strend)) ) {
-               DEBUG_r(PerlIO_printf(Perl_debug_log, "Not at start...\n"));
-               goto fail;
-           }
-           PL_regeol = strend;                 /* Used in HOP() */
-           s = HOPc(strpos, prog->check_offset_min);
-           if (SvTAIL(prog->check_substr)) {
-               slen = SvCUR(prog->check_substr);       /* >= 1 */
+           s = HOP3c(strpos, prog->check_offset_min, strend);
+           if (SvTAIL(check)) {
+               slen = SvCUR(check);    /* >= 1 */
 
                if ( strend - s > slen || strend - s < slen - 1 
                     || (strend - s == slen && strend[-1] != '\n')) {
@@ -349,30 +399,30 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                }
                /* Now should match s[0..slen-2] */
                slen--;
-               if (slen && (*SvPVX(prog->check_substr) != *s
+               if (slen && (*SvPVX(check) != *s
                             || (slen > 1
-                                && memNE(SvPVX(prog->check_substr), s, slen)))) {
+                                && memNE(SvPVX(check), s, slen)))) {
                  report_neq:
                    DEBUG_r(PerlIO_printf(Perl_debug_log, "String not equal...\n"));
                    goto fail_finish;
                }
            }
-           else if (*SvPVX(prog->check_substr) != *s
-                    || ((slen = SvCUR(prog->check_substr)) > 1
-                        && memNE(SvPVX(prog->check_substr), s, slen)))
+           else if (*SvPVX(check) != *s
+                    || ((slen = SvCUR(check)) > 1
+                        && memNE(SvPVX(check), s, slen)))
                goto report_neq;
            goto success_at_start;
+         }
        }
        /* Match is anchored, but substr is not anchored wrt beg-of-str. */
        s = strpos;
        start_shift = prog->check_offset_min; /* okay to underestimate on CC */
-       /* Should be nonnegative! */
        end_shift = prog->minlen - start_shift -
-           CHR_SVLEN(prog->check_substr) + (SvTAIL(prog->check_substr) != 0);
+           CHR_SVLEN(check) + (SvTAIL(check) != 0);
        if (!ml_anch) {
-           I32 end = prog->check_offset_max + CHR_SVLEN(prog->check_substr)
-                                        - (SvTAIL(prog->check_substr) != 0);
-           I32 eshift = strend - s - end;
+           I32 end = prog->check_offset_max + CHR_SVLEN(check)
+                                        - (SvTAIL(check) != 0);
+           I32 eshift = CHR_DIST((U8*)strend, (U8*)s) - end;
 
            if (end_shift < eshift)
                end_shift = eshift;
@@ -384,7 +434,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
        start_shift = prog->check_offset_min; /* okay to underestimate on CC */
        /* Should be nonnegative! */
        end_shift = prog->minlen - start_shift -
-           CHR_SVLEN(prog->check_substr) + (SvTAIL(prog->check_substr) != 0);
+           CHR_SVLEN(check) + (SvTAIL(check) != 0);
     }
 
 #ifdef DEBUGGING       /* 7/99: reports of failure (with the older version) */
@@ -392,12 +442,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
        Perl_croak(aTHX_ "panic: end_shift");
 #endif
 
-    check = prog->check_substr;
   restart:
     /* Find a possible match in the region s..strend by looking for
        the "check" substring in the region corrected by start/end_shift. */
     if (flags & REXEC_SCREAM) {
-       char *strbeg = SvPVX(sv);       /* XXXX Assume PV_force() on SCREAM! */
        I32 p = -1;                     /* Internal iterator of scream. */
        I32 *pp = data ? data->scream_pos : &p;
 
@@ -413,8 +461,8 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
            *data->scream_olds = s;
     }
     else
-       s = fbm_instr((unsigned char*)s + start_shift,
-                     (unsigned char*)strend - end_shift,
+       s = fbm_instr(HOP3(s, start_shift, strend),
+                     HOP3(strend, -end_shift, strbeg),
                      check, PL_multiline ? FBMrf_MULTILINE : 0);
 
     /* Update the count-of-usability, remove useless subpatterns,
@@ -432,6 +480,8 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     if (!s)
        goto fail_finish;
 
+    check_at = s;
+
     /* Finish the diagnostic message */
     DEBUG_r(PerlIO_printf(Perl_debug_log, "%ld...\n", (long)(s - i_strpos)) );
 
@@ -447,38 +497,37 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
        /* Take into account the "other" substring. */
        /* XXXX May be hopelessly wrong for UTF... */
        if (!other_last)
-           other_last = strpos - 1;
+           other_last = strpos;
        if (check == prog->float_substr) {
          do_other_anchored:
            {
-               char *last = s - start_shift, *last1, *last2;
+               char *last = HOP3c(s, -start_shift, strbeg), *last1, *last2;
                char *s1 = s;
 
-               tmp = PL_bostr;
                t = s - prog->check_offset_max;
                if (s - strpos > prog->check_offset_max  /* signed-corrected t > strpos */
                    && (!(prog->reganch & ROPT_UTF8)
-                       || (PL_bostr = strpos, /* Used in regcopmaybe() */
-                           (t = reghopmaybe_c(s, -(prog->check_offset_max)))
+                       || ((t = reghopmaybe3_c(s, -(prog->check_offset_max), strpos))
                            && t > strpos)))
                    /* EMPTY */;
                else
                    t = strpos;
-               t += prog->anchored_offset;
-               if (t <= other_last)
-                   t = other_last + 1;
-               PL_bostr = tmp;
-               last2 = last1 = strend - prog->minlen;
+               t = HOP3c(t, prog->anchored_offset, strend);
+               if (t < other_last)     /* These positions already checked */
+                   t = other_last;
+               last2 = last1 = HOP3c(strend, -prog->minlen, strbeg);
                if (last < last1)
                    last1 = last;
  /* XXXX It is not documented what units *_offsets are in.  Assume bytes.  */
                /* On end-of-str: see comment below. */
                s = fbm_instr((unsigned char*)t,
-                             (unsigned char*)last1 + prog->anchored_offset
-                                + SvCUR(prog->anchored_substr)
-                                - (SvTAIL(prog->anchored_substr)!=0),
-                             prog->anchored_substr, PL_multiline ? FBMrf_MULTILINE : 0);
-               DEBUG_r(PerlIO_printf(Perl_debug_log, "%s anchored substr `%s%.*s%s'%s",
+                             HOP3(HOP3(last1, prog->anchored_offset, strend)
+                                  + SvCUR(prog->anchored_substr),
+                                  -(SvTAIL(prog->anchored_substr)!=0), strbeg),
+                             prog->anchored_substr,
+                             PL_multiline ? FBMrf_MULTILINE : 0);
+               DEBUG_r(PerlIO_printf(Perl_debug_log,
+                       "%s anchored substr `%s%.*s%s'%s",
                        (s ? "Found" : "Contradicts"),
                        PL_colors[0],
                          (int)(SvCUR(prog->anchored_substr)
@@ -493,17 +542,16 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                    }
                    DEBUG_r(PerlIO_printf(Perl_debug_log,
                        ", trying floating at offset %ld...\n",
-                       (long)(s1 + 1 - i_strpos)));
-                   PL_regeol = strend;                 /* Used in HOP() */
-                   other_last = last1 + prog->anchored_offset;
-                   s = HOPc(last, 1);
+                       (long)(HOP3c(s1, 1, strend) - i_strpos)));
+                   other_last = HOP3c(last1, prog->anchored_offset+1, strend);
+                   s = HOP3c(last, 1, strend);
                    goto restart;
                }
                else {
                    DEBUG_r(PerlIO_printf(Perl_debug_log, " at offset %ld...\n",
                          (long)(s - i_strpos)));
-                   t = s - prog->anchored_offset;
-                   other_last = s - 1;
+                   t = HOP3c(s, -prog->anchored_offset, strbeg);
+                   other_last = HOP3c(s, 1, strend);
                    s = s1;
                    if (t == strpos)
                        goto try_at_start;
@@ -515,13 +563,14 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                char *last, *last1;
                char *s1 = s;
 
-               t = s - start_shift;
-               last1 = last = strend - prog->minlen + prog->float_min_offset;
-               if (last - t > prog->float_max_offset)
-                   last = t + prog->float_max_offset;
-               s = t + prog->float_min_offset;
-               if (s <= other_last)
-                   s = other_last + 1;
+               t = HOP3c(s, -start_shift, strbeg);
+               last1 = last =
+                   HOP3c(strend, -prog->minlen + prog->float_min_offset, strbeg);
+               if (CHR_DIST((U8*)last, (U8*)t) > prog->float_max_offset)
+                   last = HOP3c(t, prog->float_max_offset, strend);
+               s = HOP3c(t, prog->float_min_offset, strend);
+               if (s < other_last)
+                   s = other_last;
  /* XXXX It is not documented what units *_offsets are in.  Assume bytes.  */
                /* fbm_instr() takes into account exact value of end-of-str
                   if the check is SvTAIL(ed).  Since false positives are OK,
@@ -546,15 +595,14 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                    DEBUG_r(PerlIO_printf(Perl_debug_log,
                        ", trying anchored starting at offset %ld...\n",
                        (long)(s1 + 1 - i_strpos)));
-                   other_last = last;
-                   PL_regeol = strend;                 /* Used in HOP() */
-                   s = HOPc(t, 1);
+                   other_last = last + 1;
+                   s = HOP3c(t, 1, strend);
                    goto restart;
                }
                else {
                    DEBUG_r(PerlIO_printf(Perl_debug_log, " at offset %ld...\n",
                          (long)(s - i_strpos)));
-                   other_last = s - 1;
+                   other_last = s + 1;
                    s = s1;
                    if (t == strpos)
                        goto try_at_start;
@@ -564,13 +612,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     }
 
     t = s - prog->check_offset_max;
-    tmp = PL_bostr;
     if (s - strpos > prog->check_offset_max  /* signed-corrected t > strpos */
         && (!(prog->reganch & ROPT_UTF8)
-           || (PL_bostr = strpos, /* Used in regcopmaybe() */
-               ((t = reghopmaybe_c(s, -(prog->check_offset_max)))
-                && t > strpos)))) {
-       PL_bostr = tmp;
+           || ((t = reghopmaybe3_c(s, -prog->check_offset_max, strpos))
+                && t > strpos))) {
        /* Fixed substring is found far enough so that the match
           cannot start at strpos. */
       try_at_offset:
@@ -584,9 +629,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
          find_anchor:
            while (t < strend - prog->minlen) {
                if (*t == '\n') {
-                   if (t < s - prog->check_offset_min) {
+                   if (t < check_at - prog->check_offset_min) {
                        if (prog->anchored_substr) {
-                           /* We definitely contradict the found anchored
+                           /* Since we moved from the found position,
+                              we definitely contradict the found anchored
                               substr.  Due to the above check we do not
                               contradict "check" substr.
                               Thus we can arrive here only if check substr
@@ -597,14 +643,19 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                                PL_colors[0],PL_colors[1], (long)(strpos - i_strpos), (long)(strpos - i_strpos + prog->anchored_offset)));
                            goto do_other_anchored;
                        }
+                       /* We don't contradict the found floating substring. */
+                       /* XXXX Why not check for STCLASS? */
                        s = t + 1;
                        DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m at offset %ld...\n",
                            PL_colors[0],PL_colors[1], (long)(s - i_strpos)));
                        goto set_useful;
                    }
-                   DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m, restarting at offset %ld...\n",
+                   /* Position contradicts check-string */
+                   /* XXXX probably better to look for check-string
+                      than for "\n", so one should lower the limit for t? */
+                   DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m, restarting lookup for check-string at offset %ld...\n",
                        PL_colors[0],PL_colors[1], (long)(t + 1 - i_strpos)));
-                   strpos = s = t + 1;
+                   other_last = strpos = s = t + 1;
                    goto restart;
                }
                t++;
@@ -613,812 +664,1006 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                        PL_colors[0],PL_colors[1]));
            goto fail_finish;
        }
+       else {
+           DEBUG_r(PerlIO_printf(Perl_debug_log, "Starting position does not contradict /%s^%s/m...\n",
+                       PL_colors[0],PL_colors[1]));
+       }
        s = t;
       set_useful:
        ++BmUSEFUL(prog->check_substr); /* hooray/5 */
     }
     else {
-       PL_bostr = tmp;
-       /* The found string does not prohibit matching at beg-of-str
+       /* The found string does not prohibit matching at strpos,
           - no optimization of calling REx engine can be performed,
-          unless it was an MBOL and we are not after MBOL. */
+          unless it was an MBOL and we are not after MBOL,
+          or a future STCLASS check will fail this. */
       try_at_start:
        /* Even in this situation we may use MBOL flag if strpos is offset
           wrt the start of the string. */
-       if (ml_anch && sv
-           && (strpos + SvCUR(sv) != strend) && strpos[-1] != '\n') {
+       if (ml_anch && sv && !SvROK(sv) /* See prev comment on SvROK */
+           && (strpos != strbeg) && strpos[-1] != '\n'
+           /* May be due to an implicit anchor of m{.*foo}  */
+           && !(prog->reganch & ROPT_IMPLICIT))
+       {
            t = strpos;
            goto find_anchor;
        }
        DEBUG_r( if (ml_anch)
-           PerlIO_printf(Perl_debug_log, "Does not contradict /%s^%s/m...\n",
-                       PL_colors[0],PL_colors[1]);
+           PerlIO_printf(Perl_debug_log, "Position at offset %ld does not contradict /%s^%s/m...\n",
+                       (long)(strpos - i_strpos), PL_colors[0],PL_colors[1]);
        );
       success_at_start:
        if (!(prog->reganch & ROPT_NAUGHTY)     /* XXXX If strpos moved? */
+           && prog->check_substr               /* Could be deleted already */
            && --BmUSEFUL(prog->check_substr) < 0
-           && prog->check_substr == prog->float_substr) { /* boo */
+           && prog->check_substr == prog->float_substr)
+       {
            /* If flags & SOMETHING - do not do it many times on the same match */
+           DEBUG_r(PerlIO_printf(Perl_debug_log, "... Disabling check substring...\n"));
            SvREFCNT_dec(prog->check_substr);
            prog->check_substr = Nullsv;        /* disable */
            prog->float_substr = Nullsv;        /* clear */
+           check = Nullsv;                     /* abort */
            s = strpos;
+           /* XXXX This is a remnant of the old implementation.  It
+                   looks wasteful, since now INTUIT can use many
+                   other heuristics. */
            prog->reganch &= ~RE_USE_INTUIT;
        }
        else
            s = strpos;
     }
 
-    DEBUG_r(PerlIO_printf(Perl_debug_log, "%sGuessed:%s match at offset %ld\n",
-                         PL_colors[4], PL_colors[5], (long)(s - i_strpos)) );
+    /* Last resort... */
+    /* XXXX BmUSEFUL already changed, maybe multiple change is meaningful... */
+    if (prog->regstclass) {
+       /* minlen == 0 is possible if regstclass is \b or \B,
+          and the fixed substr is ''$.
+          Since minlen is already taken into account, s+1 is before strend;
+          accidentally, minlen >= 1 guaranties no false positives at s + 1
+          even for \b or \B.  But (minlen? 1 : 0) below assumes that
+          regstclass does not come from lookahead...  */
+       /* If regstclass takes bytelength more than 1: If charlength==1, OK.
+          This leaves EXACTF only, which is dealt with in find_byclass().  */
+       U8* str = (U8*)STRING(prog->regstclass);
+       int cl_l = (PL_regkind[(U8)OP(prog->regstclass)] == EXACT
+                   ? CHR_DIST(str+STR_LEN(prog->regstclass), str)
+                   : 1);
+       char *endpos = (prog->anchored_substr || ml_anch)
+               ? HOP3c(s, (prog->minlen ? cl_l : 0), strend)
+               : (prog->float_substr
+                  ? HOP3c(HOP3c(check_at, -start_shift, strbeg),
+                          cl_l, strend)
+                  : strend);
+       char *startpos = strbeg;
+
+       t = s;
+       if (prog->reganch & ROPT_UTF8) {        
+           PL_regdata = prog->data;
+           PL_bostr = startpos;
+       }
+        s = find_byclass(prog, prog->regstclass, s, endpos, startpos, 1);
+       if (!s) {
+#ifdef DEBUGGING
+           char *what;
+#endif
+           if (endpos == strend) {
+               DEBUG_r( PerlIO_printf(Perl_debug_log,
+                               "Could not match STCLASS...\n") );
+               goto fail;
+           }
+           DEBUG_r( PerlIO_printf(Perl_debug_log,
+                                  "This position contradicts STCLASS...\n") );
+           if ((prog->reganch & ROPT_ANCH) && !ml_anch)
+               goto fail;
+           /* Contradict one of substrings */
+           if (prog->anchored_substr) {
+               if (prog->anchored_substr == check) {
+                   DEBUG_r( what = "anchored" );
+                 hop_and_restart:
+                   s = HOP3c(t, 1, strend);
+                   if (s + start_shift + end_shift > strend) {
+                       /* XXXX Should be taken into account earlier? */
+                       DEBUG_r( PerlIO_printf(Perl_debug_log,
+                                              "Could not match STCLASS...\n") );
+                       goto fail;
+                   }
+                   if (!check)
+                       goto giveup;
+                   DEBUG_r( PerlIO_printf(Perl_debug_log,
+                               "Looking for %s substr starting at offset %ld...\n",
+                                what, (long)(s + start_shift - i_strpos)) );
+                   goto restart;
+               }
+               /* Have both, check_string is floating */
+               if (t + start_shift >= check_at) /* Contradicts floating=check */
+                   goto retry_floating_check;
+               /* Recheck anchored substring, but not floating... */
+               s = check_at; 
+               if (!check)
+                   goto giveup;
+               DEBUG_r( PerlIO_printf(Perl_debug_log,
+                         "Looking for anchored substr starting at offset %ld...\n",
+                         (long)(other_last - i_strpos)) );
+               goto do_other_anchored;
+           }
+           /* Another way we could have checked stclass at the
+               current position only: */
+           if (ml_anch) {
+               s = t = t + 1;
+               if (!check)
+                   goto giveup;
+               DEBUG_r( PerlIO_printf(Perl_debug_log,
+                         "Looking for /%s^%s/m starting at offset %ld...\n",
+                         PL_colors[0],PL_colors[1], (long)(t - i_strpos)) );
+               goto try_at_offset;
+           }
+           if (!prog->float_substr)    /* Could have been deleted */
+               goto fail;
+           /* Check is floating subtring. */
+         retry_floating_check:
+           t = check_at - start_shift;
+           DEBUG_r( what = "floating" );
+           goto hop_and_restart;
+       }
+       DEBUG_r( if (t != s)
+                    PerlIO_printf(Perl_debug_log, 
+                       "By STCLASS: moving %ld --> %ld\n",
+                       (long)(t - i_strpos), (long)(s - i_strpos));
+                else
+                    PerlIO_printf(Perl_debug_log, 
+                       "Does not contradict STCLASS...\n") );
+    }
+  giveup:
+    DEBUG_r(PerlIO_printf(Perl_debug_log, "%s%s:%s match at offset %ld\n",
+                         PL_colors[4], (check ? "Guessed" : "Giving up"),
+                         PL_colors[5], (long)(s - i_strpos)) );
     return s;
 
   fail_finish:                         /* Substring not found */
-    BmUSEFUL(prog->check_substr) += 5; /* hooray */
+    if (prog->check_substr)            /* could be removed already */
+       BmUSEFUL(prog->check_substr) += 5; /* hooray */
   fail:
     DEBUG_r(PerlIO_printf(Perl_debug_log, "%sMatch rejected by optimizer%s\n",
                          PL_colors[4],PL_colors[5]));
     return Nullch;
 }
 
-/*
- - regexec_flags - match a regexp against a string
- */
-I32
-Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *strend,
-             char *strbeg, I32 minend, SV *sv, void *data, U32 flags)
-/* strend: pointer to null at end of string */
-/* strbeg: real beginning of string */
-/* minend: end of match must be >=minend after stringarg. */
-/* data: May be used for some additional optimizations. */
-/* nosave: For optimizations. */
+/* We know what class REx starts with.  Try to find this position... */
+STATIC char *
+S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, char *strend, char *startpos, I32 norun)
 {
-    dTHR;
-    register char *s;
-    register regnode *c;
-    register char *startpos = stringarg;
-    register I32 tmp;
-    I32 minlen;                /* must match at least this many chars */
-    I32 dontbother = 0;        /* how many characters not to try at end */
-    I32 start_shift = 0;               /* Offset of the start to find
-                                        constant substr. */            /* CC */
-    I32 end_shift = 0;                 /* Same for the end. */         /* CC */
-    I32 scream_pos = -1;               /* Internal iterator of scream. */
-    char *scream_olds;
-    SV* oreplsv = GvSV(PL_replgv);
-
-    PL_regcc = 0;
-
-    cache_re(prog);
-#ifdef DEBUGGING
-    PL_regnarrate = PL_debug & 512;
-#endif
-
-    /* Be paranoid... */
-    if (prog == NULL || startpos == NULL) {
-       Perl_croak(aTHX_ "NULL regexp parameter");
-       return 0;
-    }
-
-    minlen = prog->minlen;
-    if (strend - startpos < minlen) goto phooey;
-
-    if (startpos == strbeg)    /* is ^ valid at stringarg? */
-       PL_regprev = '\n';
-    else {
-       PL_regprev = (U32)stringarg[-1];
-       if (!PL_multiline && PL_regprev == '\n')
-           PL_regprev = '\0';          /* force ^ to NOT match */
-    }
-
-    /* Check validity of program. */
-    if (UCHARAT(prog->program) != REG_MAGIC) {
-       Perl_croak(aTHX_ "corrupted regexp program");
-    }
-
-    PL_reg_flags = 0;
-    PL_reg_eval_set = 0;
-    PL_reg_maxiter = 0;
-
-    if (prog->reganch & ROPT_UTF8)
-       PL_reg_flags |= RF_utf8;
-
-    /* Mark beginning of line for ^ and lookbehind. */
-    PL_regbol = startpos;
-    PL_bostr  = strbeg;
-    PL_reg_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 */
-    PL_regtill = startpos+minend;
-
-    /* We start without call_cc context.  */
-    PL_reg_call_cc = 0;
-
-    /* If there is a "must appear" string, look for it. */
-    s = startpos;
-
-    if (prog->reganch & ROPT_GPOS_SEEN) { /* Need to have PL_reg_ganch */
-       MAGIC *mg;
+       I32 doevery = (prog->reganch & ROPT_SKIP) == 0;
+       char *m;
+       STRLEN ln;
+       unsigned int c1;
+       unsigned int c2;
+       char *e;
+       register I32 tmp = 1;   /* Scratch variable? */
+       register bool do_utf8 = DO_UTF8(PL_reg_sv);
 
-       if (flags & REXEC_IGNOREPOS)    /* Means: check only at start */
-           PL_reg_ganch = startpos;
-       else if (sv && SvTYPE(sv) >= SVt_PVMG
-                 && SvMAGIC(sv)
-                 && (mg = mg_find(sv, 'g')) && mg->mg_len >= 0) {
-           PL_reg_ganch = strbeg + mg->mg_len; /* Defined pos() */
-           if (prog->reganch & ROPT_ANCH_GPOS) {
-               if (s > PL_reg_ganch)
-                   goto phooey;
-               s = PL_reg_ganch;
+       /* We know what class it must start with. */
+       switch (OP(c)) {
+       case ANYOF:
+           while (s < strend) {
+               if (reginclass(c, (U8*)s, do_utf8)) {
+                   if (tmp && (norun || regtry(prog, s)))
+                       goto got_it;
+                   else
+                       tmp = doevery;
+               }
+               else
+                   tmp = 1;
+               s += do_utf8 ? UTF8SKIP(s) : 1;
            }
-       }
-       else                            /* pos() not defined */
-           PL_reg_ganch = strbeg;
-    }
-
-    if (!(flags & REXEC_CHECKED) && prog->check_substr != Nullsv) {
-       re_scream_pos_data d;
-
-       d.scream_olds = &scream_olds;
-       d.scream_pos = &scream_pos;
-       s = re_intuit_start(prog, sv, s, strend, flags, &d);
-       if (!s)
-           goto phooey;        /* not present */
-    }
-
-    DEBUG_r( if (!PL_colorset) reginitcolors() );
-    DEBUG_r(PerlIO_printf(Perl_debug_log,
-                     "%sMatching REx%s `%s%.60s%s%s' against `%s%.*s%s%s'\n",
-                     PL_colors[4],PL_colors[5],PL_colors[0],
-                     prog->precomp,
-                     PL_colors[1],
-                     (strlen(prog->precomp) > 60 ? "..." : ""),
-                     PL_colors[0],
-                     (int)(strend - startpos > 60 ? 60 : strend - startpos),
-                     startpos, PL_colors[1],
-                     (strend - startpos > 60 ? "..." : ""))
-       );
+           break;
+       case EXACTF:
+           m = STRING(c);
+           ln = STR_LEN(c);
+           if (UTF) {
+               c1 = to_utf8_lower((U8*)m);
+               c2 = to_utf8_upper((U8*)m);
+           }
+           else {
+               c1 = *(U8*)m;
+               c2 = PL_fold[c1];
+           }
+           goto do_exactf;
+       case EXACTFL:
+           m = STRING(c);
+           ln = STR_LEN(c);
+           c1 = *(U8*)m;
+           c2 = PL_fold_locale[c1];
+         do_exactf:
+           e = strend - ln;
 
-    /* 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))
-           goto got_it;
-       else if (PL_multiline || (prog->reganch & ROPT_IMPLICIT)
-                || (prog->reganch & ROPT_ANCH_MBOL)) /* XXXX SBOL? */
-       {
-           char *end;
+           if (norun && e < s)
+               e = s;                  /* Due to minlen logic of intuit() */
 
-           if (minlen)
-               dontbother = minlen - 1;
-           end = HOPc(strend, -dontbother) - 1;
-           /* for multiline we only have to try after newlines */
-           if (prog->check_substr) {
-               if (s == startpos)
-                   goto after_try;
-               while (1) {
-                   if (regtry(prog, s))
-                       goto got_it;
-                 after_try:
-                   if (s >= end)
-                       goto phooey;
-                   s = re_intuit_start(prog, sv, s + 1, strend, flags, NULL);
-                   if (!s)
-                       goto phooey;
-               }               
-           } else {
-               if (s > startpos)
-                   s--;
-               while (s < end) {
-                   if (*s++ == '\n') { /* don't need PL_utf8skip here */
-                       if (regtry(prog, s))
+           if (do_utf8) {
+               STRLEN len;
+               if (c1 == c2)
+                   while (s <= e) {
+                       if ( utf8_to_uv_simple((U8*)s, &len) == c1
+                            && regtry(prog, s) )
                            goto got_it;
+                       s += len;
+                   }
+               else
+                   while (s <= e) {
+                       UV c = utf8_to_uv_simple((U8*)s, &len);
+                       if ( (c == c1 || c == c2) && regtry(prog, s) )
+                           goto got_it;
+                       s += len;
                    }
-               }               
            }
-       }
-       goto phooey;
-    } else if (prog->reganch & ROPT_ANCH_GPOS) {
-       if (regtry(prog, PL_reg_ganch))
-           goto got_it;
-       goto phooey;
-    }
-
-    /* Messy cases:  unanchored match. */
-    if (prog->anchored_substr && prog->reganch & ROPT_SKIP) { 
-       /* we have /x+whatever/ */
-       /* it must be a one character string (XXXX Except UTF?) */
-       char ch = SvPVX(prog->anchored_substr)[0];
-       if (UTF) {
-           while (s < strend) {
-               if (*s == ch) {
-                   if (regtry(prog, s)) goto got_it;
+           else {
+               if (c1 == c2)
+                   while (s <= e) {
+                       if ( *(U8*)s == c1
+                            && (ln == 1 || !(OP(c) == EXACTF
+                                             ? ibcmp(s, m, ln)
+                                             : ibcmp_locale(s, m, ln)))
+                            && (norun || regtry(prog, s)) )
+                           goto got_it;
+                       s++;
+                   }
+               else
+                   while (s <= e) {
+                       if ( (*(U8*)s == c1 || *(U8*)s == c2)
+                            && (ln == 1 || !(OP(c) == EXACTF
+                                             ? ibcmp(s, m, ln)
+                                             : ibcmp_locale(s, m, ln)))
+                            && (norun || regtry(prog, s)) )
+                           goto got_it;
+                       s++;
+                   }
+           }
+           break;
+       case BOUNDL:
+           PL_reg_flags |= RF_tainted;
+           /* FALL THROUGH */
+       case BOUND:
+           if (do_utf8) {
+               if (s == startpos)
+                   tmp = '\n';
+               else {
+                   U8 *r = reghop3((U8*)s, -1, (U8*)startpos);
+                   
+                   tmp = (I32)utf8_to_uv(r, s - (char*)r, 0, 0);
+               }
+               tmp = ((OP(c) == BOUND ?
+                       isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
+               while (s < strend) {
+                   if (tmp == !(OP(c) == BOUND ?
+                                swash_fetch(PL_utf8_alnum, (U8*)s) :
+                                isALNUM_LC_utf8((U8*)s)))
+                   {
+                       tmp = !tmp;
+                       if ((norun || regtry(prog, s)))
+                           goto got_it;
+                   }
                    s += UTF8SKIP(s);
-                   while (s < strend && *s == ch)
-                       s += UTF8SKIP(s);
                }
-               s += UTF8SKIP(s);
            }
-       }
-       else {
-           while (s < strend) {
-               if (*s == ch) {
-                   if (regtry(prog, s)) goto got_it;
+           else {
+               tmp = (s != startpos) ? UCHARAT(s - 1) : '\n';
+               tmp = ((OP(c) == BOUND ? isALNUM(tmp) : isALNUM_LC(tmp)) != 0);
+               while (s < strend) {
+                   if (tmp ==
+                       !(OP(c) == BOUND ? isALNUM(*s) : isALNUM_LC(*s))) {
+                       tmp = !tmp;
+                       if ((norun || regtry(prog, s)))
+                           goto got_it;
+                   }
                    s++;
-                   while (s < strend && *s == ch)
-                       s++;
                }
-               s++;
-           }
-       }
-    }
-    /*SUPPRESS 560*/
-    else if (prog->anchored_substr != Nullsv
-            || (prog->float_substr != Nullsv 
-                && prog->float_max_offset < strend - s)) {
-       SV *must = prog->anchored_substr 
-           ? prog->anchored_substr : prog->float_substr;
-       I32 back_max = 
-           prog->anchored_substr ? prog->anchored_offset : prog->float_max_offset;
-       I32 back_min = 
-           prog->anchored_substr ? prog->anchored_offset : prog->float_min_offset;
-       I32 delta = back_max - back_min;
-       char *last = HOPc(strend,       /* Cannot start after this */
-                         -(I32)(CHR_SVLEN(must)
-                                - (SvTAIL(must) != 0) + back_min));
-       char *last1;            /* Last position checked before */
-
-       if (s > PL_bostr)
-           last1 = HOPc(s, -1);
-       else
-           last1 = s - 1;      /* bogus */
-
-       /* XXXX check_substr already used to find `s', can optimize if
-          check_substr==must. */
-       scream_pos = -1;
-       dontbother = end_shift;
-       strend = HOPc(strend, -dontbother);
-       while ( (s <= last) &&
-               ((flags & REXEC_SCREAM) 
-                ? (s = screaminstr(sv, must, HOPc(s, back_min) - strbeg,
-                                   end_shift, &scream_pos, 0))
-                : (s = fbm_instr((unsigned char*)HOP(s, back_min),
-                                 (unsigned char*)strend, must, 
-                                 PL_multiline ? FBMrf_MULTILINE : 0))) ) {
-           if (HOPc(s, -back_max) > last1) {
-               last1 = HOPc(s, -back_min);
-               s = HOPc(s, -back_max);
-           }
-           else {
-               char *t = (last1 >= PL_bostr) ? HOPc(last1, 1) : last1 + 1;
-
-               last1 = HOPc(s, -back_min);
-               s = t;          
            }
-           if (UTF) {
-               while (s <= last1) {
-                   if (regtry(prog, s))
+           if ((!prog->minlen && tmp) && (norun || regtry(prog, s)))
+               goto got_it;
+           break;
+       case NBOUNDL:
+           PL_reg_flags |= RF_tainted;
+           /* FALL THROUGH */
+       case NBOUND:
+           if (do_utf8) {
+               if (s == startpos)
+                   tmp = '\n';
+               else {
+                   U8 *r = reghop3((U8*)s, -1, (U8*)startpos);
+                   
+                   tmp = (I32)utf8_to_uv(r, s - (char*)r, 0, 0);
+               }
+               tmp = ((OP(c) == NBOUND ?
+                       isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
+               while (s < strend) {
+                   if (tmp == !(OP(c) == NBOUND ?
+                                swash_fetch(PL_utf8_alnum, (U8*)s) :
+                                isALNUM_LC_utf8((U8*)s)))
+                       tmp = !tmp;
+                   else if ((norun || regtry(prog, s)))
                        goto got_it;
                    s += UTF8SKIP(s);
                }
            }
            else {
-               while (s <= last1) {
-                   if (regtry(prog, s))
+               tmp = (s != startpos) ? UCHARAT(s - 1) : '\n';
+               tmp = ((OP(c) == NBOUND ?
+                       isALNUM(tmp) : isALNUM_LC(tmp)) != 0);
+               while (s < strend) {
+                   if (tmp ==
+                       !(OP(c) == NBOUND ? isALNUM(*s) : isALNUM_LC(*s)))
+                       tmp = !tmp;
+                   else if ((norun || regtry(prog, s)))
                        goto got_it;
                    s++;
                }
            }
-       }
-       goto phooey;
-    }
-    else if (c = prog->regstclass) {
-       I32 doevery = (prog->reganch & ROPT_SKIP) == 0;
-       char *m;
-       int ln;
-       int c1;
-       int c2;
-       char *e;
-
-       if (minlen)
-           dontbother = minlen - 1;
-       strend = HOPc(strend, -dontbother);     /* don't bother with what can't match */
-       tmp = 1;
-       /* We know what class it must start with. */
-       switch (OP(c)) {
-       case ANYOFUTF8:
-           while (s < strend) {
-               if (REGINCLASSUTF8(c, (U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           if ((!prog->minlen && !tmp) && (norun || regtry(prog, s)))
+               goto got_it;
+           break;
+       case ALNUM:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (swash_fetch(PL_utf8_alnum, (U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
-           break;
-       case ANYOF:
-           while (s < strend) {
-               if (REGINCLASS(c, *s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (isALNUM(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s++;
            }
            break;
-       case EXACTF:
-           m = STRING(c);
-           ln = STR_LEN(c);
-           c1 = *m;
-           c2 = PL_fold[c1];
-           goto do_exactf;
-       case EXACTFL:
-           m = STRING(c);
-           ln = STR_LEN(c);
-           c1 = *m;
-           c2 = PL_fold_locale[c1];
-         do_exactf:
-           e = strend - ln;
-
-           /* Here it is NOT UTF!  */
-           if (c1 == c2) {
-               while (s <= e) {
-                   if ( *s == c1
-                        && (ln == 1 || (OP(c) == EXACTF
-                                        ? ibcmp(s, m, ln)
-                                        : ibcmp_locale(s, m, ln)))
-                        && regtry(prog, s) )
-                       goto got_it;
-                   s++;
+       case ALNUML:
+           PL_reg_flags |= RF_tainted;
+           if (do_utf8) {
+               while (s < strend) {
+                   if (isALNUM_LC_utf8((U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-           } else {
-               while (s <= e) {
-                   if ( (*s == c1 || *s == c2)
-                        && (ln == 1 || (OP(c) == EXACTF
-                                        ? ibcmp(s, m, ln)
-                                        : ibcmp_locale(s, m, ln)))
-                        && regtry(prog, s) )
-                       goto got_it;
+           }
+           else {
+               while (s < strend) {
+                   if (isALNUM_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
                    s++;
                }
            }
            break;
-       case BOUNDL:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case BOUND:
-           if (minlen) {
-               dontbother++;
-               strend -= 1;
+       case NALNUM:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!swash_fetch(PL_utf8_alnum, (U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s += UTF8SKIP(s);
+               }
            }
-           tmp = (s != startpos) ? UCHARAT(s - 1) : PL_regprev;
-           tmp = ((OP(c) == BOUND ? isALNUM(tmp) : isALNUM_LC(tmp)) != 0);
-           while (s < strend) {
-               if (tmp == !(OP(c) == BOUND ? isALNUM(*s) : isALNUM_LC(*s))) {
-                   tmp = !tmp;
-                   if (regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isALNUM(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s++;
                }
-               s++;
            }
-           if ((minlen || tmp) && regtry(prog,s))
-               goto got_it;
            break;
-       case BOUNDLUTF8:
+       case NALNUML:
            PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case BOUNDUTF8:
-           if (minlen) {
-               dontbother++;
-               strend = reghop_c(strend, -1);
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!isALNUM_LC_utf8((U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s += UTF8SKIP(s);
+               }
            }
-           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1), 0) : PL_regprev;
-           tmp = ((OP(c) == BOUND ? isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
-           while (s < strend) {
-               if (tmp == !(OP(c) == BOUND ?
-                            swash_fetch(PL_utf8_alnum, (U8*)s) :
-                            isALNUM_LC_utf8((U8*)s)))
-               {
-                   tmp = !tmp;
-                   if (regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isALNUM_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s++;
                }
-               s += UTF8SKIP(s);
            }
-           if ((minlen || tmp) && regtry(prog,s))
-               goto got_it;
            break;
-       case NBOUNDL:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case NBOUND:
-           if (minlen) {
-               dontbother++;
-               strend -= 1;
+       case SPACE:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s += UTF8SKIP(s);
+               }
            }
-           tmp = (s != startpos) ? UCHARAT(s - 1) : PL_regprev;
-           tmp = ((OP(c) == NBOUND ? isALNUM(tmp) : isALNUM_LC(tmp)) != 0);
-           while (s < strend) {
-               if (tmp == !(OP(c) == NBOUND ? isALNUM(*s) : isALNUM_LC(*s)))
-                   tmp = !tmp;
-               else if (regtry(prog, s))
-                   goto got_it;
-               s++;
+           else {
+               while (s < strend) {
+                   if (isSPACE(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s++;
+               }
            }
-           if ((minlen || !tmp) && regtry(prog,s))
-               goto got_it;
            break;
-       case NBOUNDLUTF8:
+       case SPACEL:
            PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case NBOUNDUTF8:
-           if (minlen) {
-               dontbother++;
-               strend = reghop_c(strend, -1);
+           if (do_utf8) {
+               while (s < strend) {
+                   if (*s == ' ' || isSPACE_LC_utf8((U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s += UTF8SKIP(s);
+               }
            }
-           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1), 0) : PL_regprev;
-           tmp = ((OP(c) == NBOUND ? isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
-           while (s < strend) {
-               if (tmp == !(OP(c) == NBOUND ?
-                            swash_fetch(PL_utf8_alnum, (U8*)s) :
-                            isALNUM_LC_utf8((U8*)s)))
-                   tmp = !tmp;
-               else if (regtry(prog, s))
-                   goto got_it;
-               s += UTF8SKIP(s);
+           else {
+               while (s < strend) {
+                   if (isSPACE_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
+                   else
+                       tmp = 1;
+                   s++;
+               }
            }
-           if ((minlen || !tmp) && regtry(prog,s))
-               goto got_it;
            break;
-       case ALNUM:
-           while (s < strend) {
-               if (isALNUM(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+       case NSPACE:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!(*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s))) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s++;
            }
-           break;
-       case ALNUMUTF8:
-           while (s < strend) {
-               if (swash_fetch(PL_utf8_alnum, (U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isSPACE(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
            break;
-       case ALNUML:
+       case NSPACEL:
            PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (isALNUM_LC(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!(*s == ' ' || isSPACE_LC_utf8((U8*)s))) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s++;
            }
-           break;
-       case ALNUMLUTF8:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (isALNUM_LC_utf8((U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isSPACE_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
            break;
-       case NALNUM:
-           while (s < strend) {
-               if (!isALNUM(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+       case DIGIT:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (swash_fetch(PL_utf8_digit,(U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s++;
            }
-           break;
-       case NALNUMUTF8:
-           while (s < strend) {
-               if (!swash_fetch(PL_utf8_alnum, (U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
-           }
-           break;
-       case NALNUML:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!isALNUM_LC(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (isDIGIT(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s++;
            }
            break;
-       case NALNUMLUTF8:
+       case DIGITL:
            PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!isALNUM_LC_utf8((U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           if (do_utf8) {
+               while (s < strend) {
+                   if (isDIGIT_LC_utf8((U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
-           break;
-       case SPACE:
-           while (s < strend) {
-               if (isSPACE(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (isDIGIT_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s++;
            }
            break;
-       case SPACEUTF8:
-           while (s < strend) {
-               if (*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+       case NDIGIT:
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!swash_fetch(PL_utf8_digit,(U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
-           break;
-       case SPACEL:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (isSPACE_LC(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isDIGIT(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s++;
            }
            break;
-       case SPACELUTF8:
+       case NDIGITL:
            PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (*s == ' ' || isSPACE_LC_utf8((U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
-           }
-           break;
-       case NSPACE:
-           while (s < strend) {
-               if (!isSPACE(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           if (do_utf8) {
+               while (s < strend) {
+                   if (!isDIGIT_LC_utf8((U8*)s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s++;
            }
-           break;
-       case NSPACEUTF8:
-           while (s < strend) {
-               if (!(*s == ' ' || swash_fetch(PL_utf8_space,(U8*)s))) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
+           else {
+               while (s < strend) {
+                   if (!isDIGIT_LC(*s)) {
+                       if (tmp && (norun || regtry(prog, s)))
+                           goto got_it;
+                       else
+                           tmp = doevery;
+                   }
                    else
-                       tmp = doevery;
+                       tmp = 1;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
            break;
-       case NSPACEL:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!isSPACE_LC(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s++;
-           }
+       default:
+           Perl_croak(aTHX_ "panic: unknown regstclass %d", (int)OP(c));
            break;
-       case NSPACELUTF8:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!(*s == ' ' || isSPACE_LC_utf8((U8*)s))) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
+       }
+       return 0;
+      got_it:
+       return s;
+}
+
+/*
+ - regexec_flags - match a regexp against a string
+ */
+I32
+Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *strend,
+             char *strbeg, I32 minend, SV *sv, void *data, U32 flags)
+/* strend: pointer to null at end of string */
+/* strbeg: real beginning of string */
+/* minend: end of match must be >=minend after stringarg. */
+/* data: May be used for some additional optimizations. */
+/* nosave: For optimizations. */
+{
+    register char *s;
+    register regnode *c;
+    register char *startpos = stringarg;
+    I32 minlen;                /* must match at least this many chars */
+    I32 dontbother = 0;        /* how many characters not to try at end */
+    /* I32 start_shift = 0; */         /* Offset of the start to find
+                                        constant substr. */            /* CC */
+    I32 end_shift = 0;                 /* Same for the end. */         /* CC */
+    I32 scream_pos = -1;               /* Internal iterator of scream. */
+    char *scream_olds;
+    SV* oreplsv = GvSV(PL_replgv);
+    bool do_utf8 = DO_UTF8(sv);
+
+    PL_regcc = 0;
+
+    cache_re(prog);
+#ifdef DEBUGGING
+    PL_regnarrate = PL_debug & 512;
+#endif
+
+    /* Be paranoid... */
+    if (prog == NULL || startpos == NULL) {
+       Perl_croak(aTHX_ "NULL regexp parameter");
+       return 0;
+    }
+
+    minlen = prog->minlen;
+    if (do_utf8) {
+      if (utf8_distance((U8*)strend, (U8*)startpos) < minlen) goto phooey;
+    }
+    else {
+      if (strend - startpos < minlen) goto phooey;
+    }
+
+    if (startpos == strbeg)    /* is ^ valid at stringarg? */
+       PL_regprev = '\n';
+    else {
+        if (prog->reganch & ROPT_UTF8 && do_utf8) {
+           U8 *s = reghop3((U8*)stringarg, -1, (U8*)strbeg);
+           PL_regprev = utf8_to_uv(s, (U8*)stringarg - s, NULL, 0);
+       }
+       else
+           PL_regprev = (U32)stringarg[-1];
+       if (!PL_multiline && PL_regprev == '\n')
+           PL_regprev = '\0';          /* force ^ to NOT match */
+    }
+
+    /* Check validity of program. */
+    if (UCHARAT(prog->program) != REG_MAGIC) {
+       Perl_croak(aTHX_ "corrupted regexp program");
+    }
+
+    PL_reg_flags = 0;
+    PL_reg_eval_set = 0;
+    PL_reg_maxiter = 0;
+
+    if (prog->reganch & ROPT_UTF8)
+       PL_reg_flags |= RF_utf8;
+
+    /* Mark beginning of line for ^ and lookbehind. */
+    PL_regbol = startpos;
+    PL_bostr  = strbeg;
+    PL_reg_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 */
+    PL_regtill = startpos+minend;
+
+    /* We start without call_cc context.  */
+    PL_reg_call_cc = 0;
+
+    /* If there is a "must appear" string, look for it. */
+    s = startpos;
+
+    if (prog->reganch & ROPT_GPOS_SEEN) { /* Need to have PL_reg_ganch */
+       MAGIC *mg;
+
+       if (flags & REXEC_IGNOREPOS)    /* Means: check only at start */
+           PL_reg_ganch = startpos;
+       else if (sv && SvTYPE(sv) >= SVt_PVMG
+                 && SvMAGIC(sv)
+                 && (mg = mg_find(sv, 'g')) && mg->mg_len >= 0) {
+           PL_reg_ganch = strbeg + mg->mg_len; /* Defined pos() */
+           if (prog->reganch & ROPT_ANCH_GPOS) {
+               if (s > PL_reg_ganch)
+                   goto phooey;
+               s = PL_reg_ganch;
            }
-           break;
-       case DIGIT:
-           while (s < strend) {
-               if (isDIGIT(*s)) {
-                   if (tmp && regtry(prog, s))
+       }
+       else                            /* pos() not defined */
+           PL_reg_ganch = strbeg;
+    }
+
+    if (!(flags & REXEC_CHECKED) && prog->check_substr != Nullsv) {
+       re_scream_pos_data d;
+
+       d.scream_olds = &scream_olds;
+       d.scream_pos = &scream_pos;
+       s = re_intuit_start(prog, sv, s, strend, flags, &d);
+       if (!s)
+           goto phooey;        /* not present */
+    }
+
+    DEBUG_r( if (!PL_colorset) reginitcolors() );
+    DEBUG_r(PerlIO_printf(Perl_debug_log,
+                     "%sMatching REx%s `%s%.60s%s%s' against `%s%.*s%s%s'\n",
+                     PL_colors[4],PL_colors[5],PL_colors[0],
+                     prog->precomp,
+                     PL_colors[1],
+                     (strlen(prog->precomp) > 60 ? "..." : ""),
+                     PL_colors[0],
+                     (int)(strend - startpos > 60 ? 60 : strend - startpos),
+                     startpos, PL_colors[1],
+                     (strend - startpos > 60 ? "..." : ""))
+       );
+
+    /* 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))
+           goto got_it;
+       else if (PL_multiline || (prog->reganch & ROPT_IMPLICIT)
+                || (prog->reganch & ROPT_ANCH_MBOL)) /* XXXX SBOL? */
+       {
+           char *end;
+
+           if (minlen)
+               dontbother = minlen - 1;
+           end = HOP3c(strend, -dontbother, strbeg) - 1;
+           /* for multiline we only have to try after newlines */
+           if (prog->check_substr) {
+               if (s == startpos)
+                   goto after_try;
+               while (1) {
+                   if (regtry(prog, s))
                        goto got_it;
+                 after_try:
+                   if (s >= end)
+                       goto phooey;
+                   if (prog->reganch & RE_USE_INTUIT) {
+                       s = re_intuit_start(prog, sv, s + 1, strend, flags, NULL);
+                       if (!s)
+                           goto phooey;
+                   }
                    else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s++;
+                       s++;
+               }               
+           } else {
+               if (s > startpos)
+                   s--;
+               while (s < end) {
+                   if (*s++ == '\n') { /* don't need PL_utf8skip here */
+                       if (regtry(prog, s))
+                           goto got_it;
+                   }
+               }               
            }
-           break;
-       case DIGITUTF8:
+       }
+       goto phooey;
+    } else if (prog->reganch & ROPT_ANCH_GPOS) {
+       if (regtry(prog, PL_reg_ganch))
+           goto got_it;
+       goto phooey;
+    }
+
+    /* Messy cases:  unanchored match. */
+    if (prog->anchored_substr && prog->reganch & ROPT_SKIP) { 
+       /* we have /x+whatever/ */
+       /* it must be a one character string (XXXX Except UTF?) */
+       char ch = SvPVX(prog->anchored_substr)[0];
+#ifdef DEBUGGING
+       int did_match = 0;
+#endif
+
+       if (do_utf8) {
            while (s < strend) {
-               if (swash_fetch(PL_utf8_digit,(U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
+               if (*s == ch) {
+                   DEBUG_r( did_match = 1 );
+                   if (regtry(prog, s)) goto got_it;
+                   s += UTF8SKIP(s);
+                   while (s < strend && *s == ch)
+                       s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
                s += UTF8SKIP(s);
            }
-           break;
-       case DIGITL:
-           PL_reg_flags |= RF_tainted;
+       }
+       else {
            while (s < strend) {
-               if (isDIGIT_LC(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
+               if (*s == ch) {
+                   DEBUG_r( did_match = 1 );
+                   if (regtry(prog, s)) goto got_it;
+                   s++;
+                   while (s < strend && *s == ch)
+                       s++;
                }
-               else
-                   tmp = 1;
                s++;
            }
-           break;
-       case DIGITLUTF8:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (isDIGIT_LC_utf8((U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
-           }
-           break;
-       case NDIGIT:
-           while (s < strend) {
-               if (!isDIGIT(*s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s++;
+       }
+       DEBUG_r(did_match ||
+               PerlIO_printf(Perl_debug_log,
+                             "Did not find anchored character...\n"));
+    }
+    /*SUPPRESS 560*/
+    else if (do_utf8 == (UTF!=0) &&
+            (prog->anchored_substr != Nullsv
+             || (prog->float_substr != Nullsv 
+                 && prog->float_max_offset < strend - s))) {
+       SV *must = prog->anchored_substr 
+           ? prog->anchored_substr : prog->float_substr;
+       I32 back_max = 
+           prog->anchored_substr ? prog->anchored_offset : prog->float_max_offset;
+       I32 back_min = 
+           prog->anchored_substr ? prog->anchored_offset : prog->float_min_offset;
+       char *last = HOP3c(strend,      /* Cannot start after this */
+                         -(I32)(CHR_SVLEN(must)
+                                - (SvTAIL(must) != 0) + back_min), strbeg);
+       char *last1;            /* Last position checked before */
+#ifdef DEBUGGING
+       int did_match = 0;
+#endif
+
+       if (s > PL_bostr)
+           last1 = HOPc(s, -1);
+       else
+           last1 = s - 1;      /* bogus */
+
+       /* XXXX check_substr already used to find `s', can optimize if
+          check_substr==must. */
+       scream_pos = -1;
+       dontbother = end_shift;
+       strend = HOPc(strend, -dontbother);
+       while ( (s <= last) &&
+               ((flags & REXEC_SCREAM) 
+                ? (s = screaminstr(sv, must, HOP3c(s, back_min, strend) - strbeg,
+                                   end_shift, &scream_pos, 0))
+                : (s = fbm_instr((unsigned char*)HOP3(s, back_min, strend),
+                                 (unsigned char*)strend, must, 
+                                 PL_multiline ? FBMrf_MULTILINE : 0))) ) {
+           DEBUG_r( did_match = 1 );
+           if (HOPc(s, -back_max) > last1) {
+               last1 = HOPc(s, -back_min);
+               s = HOPc(s, -back_max);
            }
-           break;
-       case NDIGITUTF8:
-           while (s < strend) {
-               if (!swash_fetch(PL_utf8_digit,(U8*)s)) {
-                   if (tmp && regtry(prog, s))
-                       goto got_it;
-                   else
-                       tmp = doevery;
-               }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
+           else {
+               char *t = (last1 >= PL_bostr) ? HOPc(last1, 1) : last1 + 1;
+
+               last1 = HOPc(s, -back_min);
+               s = t;          
            }
-           break;
-       case NDIGITL:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!isDIGIT_LC(*s)) {
-                   if (tmp && regtry(prog, s))
+           if (do_utf8) {
+               while (s <= last1) {
+                   if (regtry(prog, s))
                        goto got_it;
-                   else
-                       tmp = doevery;
+                   s += UTF8SKIP(s);
                }
-               else
-                   tmp = 1;
-               s++;
            }
-           break;
-       case NDIGITLUTF8:
-           PL_reg_flags |= RF_tainted;
-           while (s < strend) {
-               if (!isDIGIT_LC_utf8((U8*)s)) {
-                   if (tmp && regtry(prog, s))
+           else {
+               while (s <= last1) {
+                   if (regtry(prog, s))
                        goto got_it;
-                   else
-                       tmp = doevery;
+                   s++;
                }
-               else
-                   tmp = 1;
-               s += UTF8SKIP(s);
            }
-           break;
-       default:
-           Perl_croak(aTHX_ "panic: unknown regstclass %d", (int)OP(c));
-           break;
        }
+       DEBUG_r(did_match ||
+               PerlIO_printf(Perl_debug_log, "Did not find %s substr `%s%.*s%s'%s...\n",
+                             ((must == prog->anchored_substr)
+                              ? "anchored" : "floating"),
+                             PL_colors[0],
+                             (int)(SvCUR(must) - (SvTAIL(must)!=0)),
+                             SvPVX(must),
+                             PL_colors[1], (SvTAIL(must) ? "$" : "")));
+       goto phooey;
+    }
+    else if ((c = prog->regstclass)) {
+       if (minlen && PL_regkind[(U8)OP(prog->regstclass)] != EXACT)
+           /* don't bother with what can't match */
+           strend = HOPc(strend, -(minlen - 1));
+       DEBUG_r({
+           SV *prop = sv_newmortal();
+           regprop(prop, c);
+           PerlIO_printf(Perl_debug_log, "Matching stclass `%s' against `%s'\n", SvPVX(prop), s);
+       });
+       if (find_byclass(prog, c, s, strend, startpos, 0))
+           goto got_it;
+       DEBUG_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass...\n"));
     }
     else {
        dontbother = 0;
        if (prog->float_substr != Nullsv) {     /* Trim the end. */
            char *last;
-           I32 oldpos = scream_pos;
 
            if (flags & REXEC_SCREAM) {
                last = screaminstr(sv, prog->float_substr, s - strbeg,
                                   end_shift, &scream_pos, 1); /* last one */
                if (!last)
-                   last = scream_olds; /* Only one occurence. */
+                   last = scream_olds; /* Only one occurrence. */
            }
            else {
                STRLEN len;
@@ -1440,14 +1685,19 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                        last = strend;  /* matching `$' */
                }
            }
-           if (last == NULL) goto phooey; /* Should not happen! */
+           if (last == NULL) {
+               DEBUG_r(PerlIO_printf(Perl_debug_log,
+                                     "%sCan't trim the tail, match fails (should not happen)%s\n",
+                                     PL_colors[4],PL_colors[5]));
+               goto phooey; /* Should not happen! */
+           }
            dontbother = strend - last + prog->float_min_offset;
        }
        if (minlen && (dontbother < minlen))
            dontbother = minlen - 1;
        strend -= dontbother;              /* this one's always in bytes! */
        /* We don't know much -- general case. */
-       if (UTF) {
+       if (do_utf8) {
            for (;;) {
                if (regtry(prog, s))
                    goto got_it;
@@ -1502,6 +1752,8 @@ got_it:
     return 1;
 
 phooey:
+    DEBUG_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
+                         PL_colors[4],PL_colors[5]));
     if (PL_reg_eval_set)
        restore_pos(aTHXo_ 0);
     return 0;
@@ -1513,12 +1765,14 @@ phooey:
 STATIC I32                     /* 0 failure, 1 success */
 S_regtry(pTHX_ regexp *prog, char *startpos)
 {
-    dTHR;
     register I32 i;
     register I32 *sp;
     register I32 *ep;
     CHECKPOINT lastcp;
 
+#ifdef DEBUGGING
+    PL_regindent = 0;  /* XXXX Not good when matches are reenterable... */
+#endif
     if ((prog->reganch & ROPT_EVAL_SEEN) && !PL_reg_eval_set) {
        MAGIC *mg;
 
@@ -1527,12 +1781,12 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
            PerlIO_printf(Perl_debug_log, "  setting stack tmpbase at %"IVdf"\n",
                          (IV)(PL_stack_sp - PL_stack_base));
            ));
-       SAVEINT(cxstack[cxstack_ix].blk_oldsp);
+       SAVEI32(cxstack[cxstack_ix].blk_oldsp);
        cxstack[cxstack_ix].blk_oldsp = PL_stack_sp - PL_stack_base;
        /* Otherwise OP_NEXTSTATE will free whatever on stack now.  */
        SAVETMPS;
        /* Apparently this is not needed, judging by wantarray. */
-       /* SAVEINT(cxstack[cxstack_ix].blk_gimme);
+       /* SAVEI8(cxstack[cxstack_ix].blk_gimme);
           cxstack[cxstack_ix].blk_gimme = G_SCALAR; */
 
        if (PL_reg_sv) {
@@ -1555,7 +1809,7 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
            SAVEDESTRUCTOR_X(restore_pos, 0);
         }
        if (!PL_reg_curpm)
-           New(22,PL_reg_curpm, 1, PMOP);
+           Newz(22,PL_reg_curpm, 1, PMOP);
        PL_reg_curpm->op_pmregexp = prog;
        PL_reg_oldcurpm = PL_curpm;
        PL_curpm = PL_reg_curpm;
@@ -1590,24 +1844,67 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
 
     /* XXXX What this code is doing here?!!!  There should be no need
        to do this again and again, PL_reglastparen should take care of
-       this!  */
+       this!  --ilya*/
+
+    /* Tests pat.t#187 and split.t#{13,14} seem to depend on this code.
+     * Actually, the code in regcppop() (which Ilya may be meaning by
+     * PL_reglastparen), is not needed at all by the test suite
+     * (op/regexp, op/pat, op/split), but that code is needed, oddly
+     * enough, for building DynaLoader, or otherwise this
+     * "Error: '*' not in typemap in DynaLoader.xs, line 164"
+     * will happen.  Meanwhile, this code *is* needed for the
+     * above-mentioned test suite tests to succeed.  The common theme
+     * on those tests seems to be returning null fields from matches.
+     * --jhi */
+#if 1
     sp = prog->startp;
     ep = prog->endp;
     if (prog->nparens) {
-       for (i = prog->nparens; i >= 1; i--) {
+       for (i = prog->nparens; i > *PL_reglastparen; i--) {
            *++sp = -1;
            *++ep = -1;
        }
     }
-    REGCP_SET;
+#endif
+    REGCP_SET(lastcp);
     if (regmatch(prog->program + 1)) {
        prog->endp[0] = PL_reginput - PL_bostr;
        return 1;
     }
-    REGCP_UNWIND;
+    REGCP_UNWIND(lastcp);
     return 0;
 }
 
+#define RE_UNWIND_BRANCH       1
+#define RE_UNWIND_BRANCHJ      2
+
+union re_unwind_t;
+
+typedef struct {               /* XX: makes sense to enlarge it... */
+    I32 type;
+    I32 prev;
+    CHECKPOINT lastcp;
+} re_unwind_generic_t;
+
+typedef struct {
+    I32 type;
+    I32 prev;
+    CHECKPOINT lastcp;
+    I32 lastparen;
+    regnode *next;
+    char *locinput;
+    I32 nextchr;
+#ifdef DEBUGGING
+    int regindent;
+#endif
+} re_unwind_branch_t;
+
+typedef union re_unwind_t {
+    I32 type;
+    re_unwind_generic_t generic;
+    re_unwind_branch_t branch;
+} re_unwind_t;
+
 /*
  - regmatch - main matching routine
  *
@@ -1625,7 +1922,6 @@ S_regtry(pTHX_ regexp *prog, char *startpos)
 STATIC I32                     /* 0 failure, 1 success */
 S_regmatch(pTHX_ regnode *prog)
 {
-    dTHR;
     register regnode *scan;    /* Current node. */
     regnode *next;             /* Next node. */
     regnode *inner;            /* Next node in internal branch. */
@@ -1637,6 +1933,10 @@ S_regmatch(pTHX_ regnode *prog)
     register char *locinput = PL_reginput;
     register I32 c1, c2, paren;        /* case fold search, parenth */
     int minmod = 0, sw = 0, logical = 0;
+    I32 unwind = 0;
+    I32 firstcp = PL_savestack_ix;
+    register bool do_utf8 = DO_UTF8(PL_reg_sv);
+
 #ifdef DEBUGGING
     PL_regindent++;
 #endif
@@ -1646,7 +1946,7 @@ S_regmatch(pTHX_ regnode *prog)
     scan = prog;
     while (scan != NULL) {
 #define sayNO_L (logical ? (logical = 0, sw = 0, goto cont) : sayNO)
-#ifdef DEBUGGING
+#if 1
 #  define sayYES goto yes
 #  define sayNO goto no
 #  define sayYES_FINAL goto yes_final
@@ -1668,20 +1968,25 @@ S_regmatch(pTHX_ regnode *prog)
            SV *prop = sv_newmortal();
            int docolor = *PL_colors[0];
            int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
-           int l = (PL_regeol - locinput > taill ? taill : PL_regeol - locinput);
+           int l = (PL_regeol - locinput) > taill ? taill : (PL_regeol - locinput);
            /* The part of the string before starttry has one color
               (pref0_len chars), between starttry and current
               position another one (pref_len - pref0_len chars),
               after the current position the third one.
               We assume that pref0_len <= pref_len, otherwise we
               decrease pref0_len.  */
-           int pref_len = (locinput - PL_bostr > (5 + taill) - l 
-                           ? (5 + taill) - l : locinput - PL_bostr);
-           int pref0_len = pref_len  - (locinput - PL_reg_starttry);
+           int pref_len = (locinput - PL_bostr) > (5 + taill) - l 
+               ? (5 + taill) - l : locinput - PL_bostr;
+           int pref0_len;
 
+           while (UTF8_IS_CONTINUATION(*(U8*)(locinput - pref_len)))
+               pref_len++;
+           pref0_len = pref_len  - (locinput - PL_reg_starttry);
            if (l + pref_len < (5 + taill) && l < PL_regeol - locinput)
                l = ( PL_regeol - locinput > (5 + taill) - pref_len 
                      ? (5 + taill) - pref_len : PL_regeol - locinput);
+           while (UTF8_IS_CONTINUATION(*(U8*)(locinput + l)))
+               l--;
            if (pref0_len < 0)
                pref0_len = 0;
            if (pref0_len > pref_len)
@@ -1726,7 +2031,7 @@ S_regmatch(pTHX_ regnode *prog)
            }
            sayNO;
        case SBOL:
-           if (locinput == PL_regbol && PL_regprev == '\n')
+           if (locinput == PL_bostr)
                break;
            sayNO;
        case GPOS:
@@ -1754,8 +2059,8 @@ S_regmatch(pTHX_ regnode *prog)
            if (PL_regeol != locinput)
                sayNO;
            break;
-       case SANYUTF8:
-           if (nextchr & 0x80) {
+       case SANY:
+           if (do_utf8) {
                locinput += PL_utf8skip[nextchr];
                if (locinput > PL_regeol)
                    sayNO;
@@ -1766,31 +2071,47 @@ S_regmatch(pTHX_ regnode *prog)
                sayNO;
            nextchr = UCHARAT(++locinput);
            break;
-       case SANY:
-           if (!nextchr && locinput >= PL_regeol)
+       case REG_ANY:
+           if ((!nextchr && locinput >= PL_regeol) || nextchr == '\n')
                sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case ANYUTF8:
-           if (nextchr & 0x80) {
+           if (do_utf8) {
                locinput += PL_utf8skip[nextchr];
                if (locinput > PL_regeol)
                    sayNO;
                nextchr = UCHARAT(locinput);
-               break;
            }
-           if (!nextchr && locinput >= PL_regeol || nextchr == '\n')
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case REG_ANY:
-           if (!nextchr && locinput >= PL_regeol || nextchr == '\n')
-               sayNO;
-           nextchr = UCHARAT(++locinput);
+           else
+               nextchr = UCHARAT(++locinput);
            break;
        case EXACT:
            s = STRING(scan);
            ln = STR_LEN(scan);
+           if (do_utf8 != (UTF!=0)) {
+               char *l = locinput;
+               char *e = s + ln;
+               STRLEN len;
+               if (do_utf8)
+                   while (s < e) {
+                       if (l >= PL_regeol)
+                           sayNO;
+                       if (*((U8*)s) != utf8_to_uv_simple((U8*)l, &len))
+                           sayNO;
+                       s++;
+                       l += len;
+                   }
+               else
+                   while (s < e) {
+                       if (l >= PL_regeol)
+                           sayNO;
+                       if (*((U8*)l) != utf8_to_uv_simple((U8*)s, &len))
+                           sayNO;
+                       s += len;
+                       l++;
+                   }
+               locinput = l;
+               nextchr = UCHARAT(locinput);
+               break;
+           }
            /* Inline the first character, for speed. */
            if (UCHARAT(s) != nextchr)
                sayNO;
@@ -1808,20 +2129,19 @@ S_regmatch(pTHX_ regnode *prog)
            s = STRING(scan);
            ln = STR_LEN(scan);
 
-           if (UTF) {
+           if (do_utf8) {
                char *l = locinput;
-               char *e = s + ln;
+               char *e;
+               e = s + ln;
                c1 = OP(scan) == EXACTF;
                while (s < e) {
-                   if (l >= PL_regeol)
-                       sayNO;
-                   if (utf8_to_uv((U8*)s, 0) != (c1 ?
-                                                 toLOWER_utf8((U8*)l) :
-                                                 toLOWER_LC_utf8((U8*)l)))
-                   {
+                   if (l >= PL_regeol) {
                        sayNO;
                    }
-                   s += UTF8SKIP(s);
+                   if ((UTF ? utf8_to_uv((U8*)s, e - s, 0, 0) : *((U8*)s)) !=
+                       (c1 ? toLOWER_utf8((U8*)l) : toLOWER_LC_utf8((U8*)l)))
+                           sayNO;
+                   s += UTF ? UTF8SKIP(s) : 1;
                    l += UTF8SKIP(l);
                }
                locinput = l;
@@ -1843,42 +2163,33 @@ S_regmatch(pTHX_ regnode *prog)
            locinput += ln;
            nextchr = UCHARAT(locinput);
            break;
-       case ANYOFUTF8:
-           if (!REGINCLASSUTF8(scan, (U8*)locinput))
-               sayNO;
-           if (locinput >= PL_regeol)
-               sayNO;
-           locinput += PL_utf8skip[nextchr];
-           nextchr = UCHARAT(locinput);
-           break;
        case ANYOF:
-           if (nextchr < 0)
+           if (do_utf8) {
+               if (!reginclass(scan, (U8*)locinput, do_utf8))
+                   sayNO;
+               if (locinput >= PL_regeol)
+                   sayNO;
+               locinput += PL_utf8skip[nextchr];
                nextchr = UCHARAT(locinput);
-           if (!REGINCLASS(scan, nextchr))
-               sayNO;
-           if (!nextchr && locinput >= PL_regeol)
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case ALNUML:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case ALNUM:
-           if (!nextchr)
-               sayNO;
-           if (!(OP(scan) == ALNUM
-                 ? isALNUM(nextchr) : isALNUM_LC(nextchr)))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
+           }
+           else {
+               if (nextchr < 0)
+                   nextchr = UCHARAT(locinput);
+               if (!reginclass(scan, (U8*)locinput, do_utf8))
+                   sayNO;
+               if (!nextchr && locinput >= PL_regeol)
+                   sayNO;
+               nextchr = UCHARAT(++locinput);
+           }
            break;
-       case ALNUMLUTF8:
+       case ALNUML:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
-       case ALNUMUTF8:
+       case ALNUM:
            if (!nextchr)
                sayNO;
-           if (nextchr & 0x80) {
-               if (!(OP(scan) == ALNUMUTF8
+           if (do_utf8) {
+               if (!(OP(scan) == ALNUM
                      ? swash_fetch(PL_utf8_alnum, (U8*)locinput)
                      : isALNUM_LC_utf8((U8*)locinput)))
                {
@@ -1888,7 +2199,7 @@ S_regmatch(pTHX_ regnode *prog)
                nextchr = UCHARAT(locinput);
                break;
            }
-           if (!(OP(scan) == ALNUMUTF8
+           if (!(OP(scan) == ALNUM
                  ? isALNUM(nextchr) : isALNUM_LC(nextchr)))
                sayNO;
            nextchr = UCHARAT(++locinput);
@@ -1899,19 +2210,8 @@ S_regmatch(pTHX_ regnode *prog)
        case NALNUM:
            if (!nextchr && locinput >= PL_regeol)
                sayNO;
-           if (OP(scan) == NALNUM
-               ? isALNUM(nextchr) : isALNUM_LC(nextchr))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case NALNUMLUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case NALNUMUTF8:
-           if (!nextchr && locinput >= PL_regeol)
-               sayNO;
-           if (nextchr & 0x80) {
-               if (OP(scan) == NALNUMUTF8
+           if (do_utf8) {
+               if (OP(scan) == NALNUM
                    ? swash_fetch(PL_utf8_alnum, (U8*)locinput)
                    : isALNUM_LC_utf8((U8*)locinput))
                {
@@ -1921,7 +2221,7 @@ S_regmatch(pTHX_ regnode *prog)
                nextchr = UCHARAT(locinput);
                break;
            }
-           if (OP(scan) == NALNUMUTF8
+           if (OP(scan) == NALNUM
                ? isALNUM(nextchr) : isALNUM_LC(nextchr))
                sayNO;
            nextchr = UCHARAT(++locinput);
@@ -1933,91 +2233,78 @@ S_regmatch(pTHX_ regnode *prog)
        case BOUND:
        case NBOUND:
            /* was last char in word? */
-           ln = (locinput != PL_regbol) ? UCHARAT(locinput - 1) : PL_regprev;
-           if (OP(scan) == BOUND || OP(scan) == NBOUND) {
-               ln = isALNUM(ln);
-               n = isALNUM(nextchr);
-           }
-           else {
-               ln = isALNUM_LC(ln);
-               n = isALNUM_LC(nextchr);
-           }
-           if (((!ln) == (!n)) == (OP(scan) == BOUND || OP(scan) == BOUNDL))
-               sayNO;
-           break;
-       case BOUNDLUTF8:
-       case NBOUNDLUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case BOUNDUTF8:
-       case NBOUNDUTF8:
-           /* was last char in word? */
-           ln = (locinput != PL_regbol)
-               ? utf8_to_uv(reghop((U8*)locinput, -1), 0) : PL_regprev;
-           if (OP(scan) == BOUNDUTF8 || OP(scan) == NBOUNDUTF8) {
-               ln = isALNUM_uni(ln);
-               n = swash_fetch(PL_utf8_alnum, (U8*)locinput);
+           if (do_utf8) {
+               if (locinput == PL_regbol)
+                   ln = PL_regprev;
+               else {
+                   U8 *r = reghop((U8*)locinput, -1);
+                   
+                   ln = utf8_to_uv(r, s - (char*)r, 0, 0);
+               }
+               if (OP(scan) == BOUND || OP(scan) == NBOUND) {
+                   ln = isALNUM_uni(ln);
+                   n = swash_fetch(PL_utf8_alnum, (U8*)locinput);
+               }
+               else {
+                   ln = isALNUM_LC_uni(ln);
+                   n = isALNUM_LC_utf8((U8*)locinput);
+               }
            }
            else {
-               ln = isALNUM_LC_uni(ln);
-               n = isALNUM_LC_utf8((U8*)locinput);
+               ln = (locinput != PL_regbol) ?
+                   UCHARAT(locinput - 1) : PL_regprev;
+               if (OP(scan) == BOUND || OP(scan) == NBOUND) {
+                   ln = isALNUM(ln);
+                   n = isALNUM(nextchr);
+               }
+               else {
+                   ln = isALNUM_LC(ln);
+                   n = isALNUM_LC(nextchr);
+               }
            }
-           if (((!ln) == (!n)) == (OP(scan) == BOUNDUTF8 || OP(scan) == BOUNDLUTF8))
-               sayNO;
+           if (((!ln) == (!n)) == (OP(scan) == BOUND ||
+                                   OP(scan) == BOUNDL))
+                   sayNO;
            break;
        case SPACEL:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case SPACE:
-           if (!nextchr && locinput >= PL_regeol)
-               sayNO;
-           if (!(OP(scan) == SPACE
-                 ? isSPACE(nextchr) : isSPACE_LC(nextchr)))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case SPACELUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case SPACEUTF8:
-           if (!nextchr && locinput >= PL_regeol)
+           if (!nextchr)
                sayNO;
-           if (nextchr & 0x80) {
-               if (!(OP(scan) == SPACEUTF8
-                     ? swash_fetch(PL_utf8_space,(U8*)locinput)
-                     : isSPACE_LC_utf8((U8*)locinput)))
-               {
-                   sayNO;
+           if (do_utf8) {
+               if (nextchr & 0x80) {
+                   if (!(OP(scan) == SPACE
+                         ? swash_fetch(PL_utf8_space, (U8*)locinput)
+                         : isSPACE_LC_utf8((U8*)locinput)))
+                   {
+                       sayNO;
+                   }
+                   locinput += PL_utf8skip[nextchr];
+                   nextchr = UCHARAT(locinput);
+                   break;
                }
-               locinput += PL_utf8skip[nextchr];
-               nextchr = UCHARAT(locinput);
-               break;
+               if (!(OP(scan) == SPACE
+                     ? isSPACE(nextchr) : isSPACE_LC(nextchr)))
+                   sayNO;
+               nextchr = UCHARAT(++locinput);
+           }
+           else {
+               if (!(OP(scan) == SPACE
+                     ? isSPACE(nextchr) : isSPACE_LC(nextchr)))
+                   sayNO;
+               nextchr = UCHARAT(++locinput);
            }
-           if (!(OP(scan) == SPACEUTF8
-                 ? isSPACE(nextchr) : isSPACE_LC(nextchr)))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
            break;
        case NSPACEL:
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NSPACE:
-           if (!nextchr)
-               sayNO;
-           if (OP(scan) == SPACE
-               ? isSPACE(nextchr) : isSPACE_LC(nextchr))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case NSPACELUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case NSPACEUTF8:
-           if (!nextchr)
+           if (!nextchr && locinput >= PL_regeol)
                sayNO;
-           if (nextchr & 0x80) {
-               if (OP(scan) == NSPACEUTF8
-                   ? swash_fetch(PL_utf8_space,(U8*)locinput)
+           if (do_utf8) {
+               if (OP(scan) == NSPACE
+                   ? swash_fetch(PL_utf8_space, (U8*)locinput)
                    : isSPACE_LC_utf8((U8*)locinput))
                {
                    sayNO;
@@ -2026,7 +2313,7 @@ S_regmatch(pTHX_ regnode *prog)
                nextchr = UCHARAT(locinput);
                break;
            }
-           if (OP(scan) == NSPACEUTF8
+           if (OP(scan) == NSPACE
                ? isSPACE(nextchr) : isSPACE_LC(nextchr))
                sayNO;
            nextchr = UCHARAT(++locinput);
@@ -2035,23 +2322,12 @@ S_regmatch(pTHX_ regnode *prog)
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case DIGIT:
-           if (!nextchr && locinput >= PL_regeol)
-               sayNO;
-           if (!(OP(scan) == DIGIT
-                 ? isDIGIT(nextchr) : isDIGIT_LC(nextchr)))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case DIGITLUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case DIGITUTF8:
            if (!nextchr)
                sayNO;
-           if (nextchr & 0x80) {
-               if (OP(scan) == NDIGITUTF8
-                   ? swash_fetch(PL_utf8_digit,(U8*)locinput)
-                   : isDIGIT_LC_utf8((U8*)locinput))
+           if (do_utf8) {
+               if (!(OP(scan) == DIGIT
+                     ? swash_fetch(PL_utf8_digit, (U8*)locinput)
+                     : isDIGIT_LC_utf8((U8*)locinput)))
                {
                    sayNO;
                }
@@ -2059,7 +2335,8 @@ S_regmatch(pTHX_ regnode *prog)
                nextchr = UCHARAT(locinput);
                break;
            }
-           if (!isDIGIT(nextchr))
+           if (!(OP(scan) == DIGIT
+                 ? isDIGIT(nextchr) : isDIGIT_LC(nextchr)))
                sayNO;
            nextchr = UCHARAT(++locinput);
            break;
@@ -2067,27 +2344,21 @@ S_regmatch(pTHX_ regnode *prog)
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NDIGIT:
-           if (!nextchr)
-               sayNO;
-           if (OP(scan) == DIGIT
-               ? isDIGIT(nextchr) : isDIGIT_LC(nextchr))
-               sayNO;
-           nextchr = UCHARAT(++locinput);
-           break;
-       case NDIGITLUTF8:
-           PL_reg_flags |= RF_tainted;
-           /* FALL THROUGH */
-       case NDIGITUTF8:
            if (!nextchr && locinput >= PL_regeol)
                sayNO;
-           if (nextchr & 0x80) {
-               if (swash_fetch(PL_utf8_digit,(U8*)locinput))
+           if (do_utf8) {
+               if (OP(scan) == NDIGIT
+                   ? swash_fetch(PL_utf8_digit, (U8*)locinput)
+                   : isDIGIT_LC_utf8((U8*)locinput))
+               {
                    sayNO;
+               }
                locinput += PL_utf8skip[nextchr];
                nextchr = UCHARAT(locinput);
                break;
            }
-           if (isDIGIT(nextchr))
+           if (OP(scan) == NDIGIT
+               ? isDIGIT(nextchr) : isDIGIT_LC(nextchr))
                sayNO;
            nextchr = UCHARAT(++locinput);
            break;
@@ -2115,7 +2386,7 @@ S_regmatch(pTHX_ regnode *prog)
                break;
 
            s = PL_bostr + ln;
-           if (UTF && OP(scan) != REF) {       /* REF can do byte comparison */
+           if (do_utf8 && OP(scan) != REF) {   /* REF can do byte comparison */
                char *l = locinput;
                char *e = PL_bostr + PL_regendp[n];
                /*
@@ -2244,7 +2515,7 @@ S_regmatch(pTHX_ regnode *prog)
                    PL_regcc = 0;
                    
                    cp = regcppush(0);  /* Save *all* the positions. */
-                   REGCP_SET;
+                   REGCP_SET(lastcp);
                    cache_re(re);
                    state.ss = PL_savestack_ix;
                    *PL_reglastparen = 0;
@@ -2274,7 +2545,7 @@ S_regmatch(pTHX_ regnode *prog)
                        sayYES;
                    }
                    ReREFCNT_dec(re);
-                   REGCP_UNWIND;
+                   REGCP_UNWIND(lastcp);
                    regcppop();
                    PL_reg_call_cc = state.prev;
                    PL_regcc = state.cc;
@@ -2401,12 +2672,18 @@ S_regmatch(pTHX_ regnode *prog)
        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);
                cc.oldcc = PL_regcc;
                PL_regcc = &cc;
-               cc.parenfloor = *PL_reglastparen;
+               /* XXXX Probably it is better to teach regpush to support
+                  parenfloor > PL_regsize... */
+               if (parenfloor > *PL_reglastparen)
+                   parenfloor = *PL_reglastparen; /* Pessimization... */
+               cc.parenfloor = parenfloor;
                cc.cur = -1;
                cc.min = ARG1(scan);
                cc.max  = ARG2(scan);
@@ -2529,22 +2806,22 @@ S_regmatch(pTHX_ regnode *prog)
                    if (PL_regcc)
                        ln = PL_regcc->cur;
                    cp = regcppush(cc->parenfloor);
-                   REGCP_SET;
+                   REGCP_SET(lastcp);
                    if (regmatch(cc->next)) {
                        regcpblow(cp);
                        sayYES; /* All done. */
                    }
-                   REGCP_UNWIND;
+                   REGCP_UNWIND(lastcp);
                    regcppop();
                    if (PL_regcc)
                        PL_regcc->cur = ln;
                    PL_regcc = cc;
 
                    if (n >= cc->max) { /* Maximum greed exceeded? */
-                       if (ckWARN(WARN_UNSAFE) && n >= REG_INFTY 
+                       if (ckWARN(WARN_REGEXP) && n >= REG_INFTY 
                            && !(PL_reg_flags & RF_warned)) {
                            PL_reg_flags |= RF_warned;
-                           Perl_warner(aTHX_ WARN_UNSAFE, "%s limit (%d) exceeded",
+                           Perl_warner(aTHX_ WARN_REGEXP, "%s limit (%d) exceeded",
                                 "Complex regular subexpression recursion",
                                 REG_INFTY - 1);
                        }
@@ -2561,12 +2838,12 @@ S_regmatch(pTHX_ regnode *prog)
                    cc->cur = n;
                    cc->lastloc = locinput;
                    cp = regcppush(cc->parenfloor);
-                   REGCP_SET;
+                   REGCP_SET(lastcp);
                    if (regmatch(cc->scan)) {
                        regcpblow(cp);
                        sayYES;
                    }
-                   REGCP_UNWIND;
+                   REGCP_UNWIND(lastcp);
                    regcppop();
                    cc->cur = n - 1;
                    cc->lastloc = lastloc;
@@ -2579,12 +2856,12 @@ S_regmatch(pTHX_ regnode *prog)
                    cp = regcppush(cc->parenfloor);
                    cc->cur = n;
                    cc->lastloc = locinput;
-                   REGCP_SET;
+                   REGCP_SET(lastcp);
                    if (regmatch(cc->scan)) {
                        regcpblow(cp);
                        sayYES;
                    }
-                   REGCP_UNWIND;
+                   REGCP_UNWIND(lastcp);
                    regcppop();         /* Restore some previous $<digit>s? */
                    PL_reginput = locinput;
                    DEBUG_r(
@@ -2593,10 +2870,10 @@ S_regmatch(pTHX_ regnode *prog)
                                      REPORT_CODE_OFF+PL_regindent*2, "")
                        );
                }
-               if (ckWARN(WARN_UNSAFE) && n >= REG_INFTY 
+               if (ckWARN(WARN_REGEXP) && n >= REG_INFTY 
                        && !(PL_reg_flags & RF_warned)) {
                    PL_reg_flags |= RF_warned;
-                   Perl_warner(aTHX_ WARN_UNSAFE, "%s limit (%d) exceeded",
+                   Perl_warner(aTHX_ WARN_REGEXP, "%s limit (%d) exceeded",
                         "Complex regular subexpression recursion",
                         REG_INFTY - 1);
                }
@@ -2630,30 +2907,30 @@ S_regmatch(pTHX_ regnode *prog)
                if (OP(next) != c1)     /* No choice. */
                    next = inner;       /* Avoid recursion. */
                else {
-                   int lastparen = *PL_reglastparen;
+                   I32 lastparen = *PL_reglastparen;
+                   I32 unwind1;
+                   re_unwind_branch_t *uw;
+
+                   /* 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)
+                               ? RE_UNWIND_BRANCH
+                               : RE_UNWIND_BRANCHJ);
+                   uw->lastparen = lastparen;
+                   uw->next = next;
+                   uw->locinput = locinput;
+                   uw->nextchr = nextchr;
+#ifdef DEBUGGING
+                   uw->regindent = ++PL_regindent;
+#endif
 
-                   REGCP_SET;
-                   do {
-                       PL_reginput = locinput;
-                       if (regmatch(inner))
-                           sayYES;
-                       REGCP_UNWIND;
-                       for (n = *PL_reglastparen; n > lastparen; n--)
-                           PL_regendp[n] = -1;
-                       *PL_reglastparen = n;
-                       scan = next;
-                       /*SUPPRESS 560*/
-                       if (n = (c1 == BRANCH ? NEXT_OFF(next) : ARG(next)))
-                           next += n;
-                       else
-                           next = NULL;
-                       inner = NEXTOPER(scan);
-                       if (c1 == BRANCHJ) {
-                           inner = NEXTOPER(inner);
-                       }
-                   } while (scan != NULL && OP(scan) == c1);
-                   sayNO;
-                   /* NOTREACHED */
+                   REGCP_SET(uw->lastcp);
+
+                   /* Now go into the first branch */
+                   next = inner;
                }
            }
            break;
@@ -2703,7 +2980,7 @@ S_regmatch(pTHX_ regnode *prog)
                }
                else
                    c1 = c2 = -1000;
-               REGCP_SET;
+               REGCP_SET(lastcp);
                /* This may be improved if l == 0.  */
                while (n >= ln || (n == REG_INFTY && ln > 0 && l)) { /* ln overflow ? */
                    /* If it could work, try it. */
@@ -2722,7 +2999,7 @@ S_regmatch(pTHX_ regnode *prog)
                        }
                        if (regmatch(next))
                            sayYES;
-                       REGCP_UNWIND;
+                       REGCP_UNWIND(lastcp);
                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;
@@ -2745,9 +3022,9 @@ S_regmatch(pTHX_ regnode *prog)
                locinput = PL_reginput;
                DEBUG_r(
                    PerlIO_printf(Perl_debug_log,
-                                 "%*s  matched %d times, len=%"IVdf"...\n",
+                                 "%*s  matched %"IVdf" times, len=%"IVdf"...\n",
                                  (int)(REPORT_CODE_OFF+PL_regindent*2), "",
-                                 n, (IV)l)
+                                 (IV) n, (IV)l)
                    );
                if (n >= ln) {
                    if (PL_regkind[(U8)OP(next)] == EXACT) {
@@ -2762,7 +3039,7 @@ S_regmatch(pTHX_ regnode *prog)
                    else
                        c1 = c2 = -1000;
                }
-               REGCP_SET;
+               REGCP_SET(lastcp);
                while (n >= ln) {
                    /* If it could work, try it. */
                    if (c1 == -1000 ||
@@ -2784,7 +3061,7 @@ S_regmatch(pTHX_ regnode *prog)
                        }
                        if (regmatch(next))
                            sayYES;
-                       REGCP_UNWIND;
+                       REGCP_UNWIND(lastcp);
                    }
                    /* Couldn't or didn't -- back up. */
                    n--;
@@ -2828,13 +3105,23 @@ S_regmatch(pTHX_ regnode *prog)
            * when we know what character comes next.
            */
            if (PL_regkind[(U8)OP(next)] == EXACT) {
-               c1 = (U8)*STRING(next);
-               if (OP(next) == EXACTF)
-                   c2 = PL_fold[c1];
-               else if (OP(next) == EXACTFL)
-                   c2 = PL_fold_locale[c1];
-               else
-                   c2 = c1;
+               U8 *s = (U8*)STRING(next);
+               if (!UTF) {
+                   c2 = c1 = *s;
+                   if (OP(next) == EXACTF)
+                       c2 = PL_fold[c1];
+                   else if (OP(next) == EXACTFL)
+                       c2 = PL_fold_locale[c1];
+               }
+               else { /* UTF */
+                   if (OP(next) == EXACTF) {
+                       c1 = to_utf8_lower(s);
+                       c2 = to_utf8_upper(s);
+                   }
+                   else {
+                       c2 = c1 = utf8_to_uv_simple(s, NULL);
+                   }
+               }
            }
            else
                c1 = c2 = -1000;
@@ -2845,68 +3132,95 @@ S_regmatch(pTHX_ regnode *prog)
                if (ln && regrepeat(scan, ln) < ln)
                    sayNO;
                locinput = PL_reginput;
-               REGCP_SET;
+               REGCP_SET(lastcp);
                if (c1 != -1000) {
-                   char *e = locinput + n - ln; /* Should not check after this */
+                   char *e; /* Should not check after this */
                    char *old = locinput;
 
-                   if (e >= PL_regeol || (n == REG_INFTY))
+                   if  (n == REG_INFTY) {
                        e = PL_regeol - 1;
+                       if (do_utf8)
+                           while (UTF8_IS_CONTINUATION(*(U8*)e))
+                               e--;
+                   }
+                   else if (do_utf8) {
+                       int m = n - ln;
+                       for (e = locinput;
+                            m >0 && e + UTF8SKIP(e) <= PL_regeol; m--)
+                           e += UTF8SKIP(e);
+                   }
+                   else {
+                       e = locinput + n - ln;
+                       if (e >= PL_regeol)
+                           e = PL_regeol - 1;
+                   }
                    while (1) {
+                       int count;
                        /* Find place 'next' could work */
-                       if (c1 == c2) {
-                           while (locinput <= e && *locinput != c1)
-                               locinput++;
-                       } else {
-                           while (locinput <= e 
-                                  && *locinput != c1
-                                  && *locinput != c2)
-                               locinput++;                         
+                       if (!do_utf8) {
+                           if (c1 == c2) {
+                               while (locinput <= e && *locinput != c1)
+                                   locinput++;
+                           } else {
+                               while (locinput <= e 
+                                      && *locinput != c1
+                                      && *locinput != c2)
+                                   locinput++;
+                           }
+                           count = locinput - old;
+                       }
+                       else {
+                           STRLEN len;
+                           if (c1 == c2) {
+                               for (count = 0;
+                                    locinput <= e &&
+                                        utf8_to_uv_simple((U8*)locinput, &len) != c1;
+                                    count++)
+                                   locinput += len;
+                               
+                           } else {
+                               for (count = 0; locinput <= e; count++) {
+                                   UV c = utf8_to_uv_simple((U8*)locinput, &len);
+                                   if (c == c1 || c == c2)
+                                       break;
+                                   locinput += len;                        
+                               }
+                           }
                        }
                        if (locinput > e) 
                            sayNO;
                        /* PL_reginput == old now */
                        if (locinput != old) {
                            ln = 1;     /* Did some */
-                           if (regrepeat(scan, locinput - old) <
-                                locinput - old)
+                           if (regrepeat(scan, count) < count)
                                sayNO;
                        }
                        /* PL_reginput == locinput now */
-                       if (paren) {
-                           if (ln) {
-                               PL_regstartp[paren] = HOPc(locinput, -1) - PL_bostr;
-                               PL_regendp[paren] = locinput - PL_bostr;
-                           }
-                           else
-                               PL_regendp[paren] = -1;
-                       }
-                       if (regmatch(next))
-                           sayYES;
+                       TRYPAREN(paren, ln, locinput);
                        PL_reginput = locinput; /* Could be reset... */
-                       REGCP_UNWIND;
+                       REGCP_UNWIND(lastcp);
                        /* Couldn't or didn't -- move forward. */
-                       old = locinput++;
+                       old = locinput;
+                       if (do_utf8)
+                           locinput += UTF8SKIP(locinput);
+                       else
+                           locinput++;
                    }
                }
                else
                while (n >= ln || (n == REG_INFTY && ln > 0)) { /* ln overflow ? */
+                   UV c;
+                   if (c1 != -1000) {
+                       if (do_utf8)
+                           c = utf8_to_uv_simple((U8*)PL_reginput, NULL);
+                       else
+                           c = UCHARAT(PL_reginput); 
+                   }
                    /* If it could work, try it. */
-                   if (c1 == -1000 ||
-                       UCHARAT(PL_reginput) == c1 ||
-                       UCHARAT(PL_reginput) == c2)
+                   if (c1 == -1000 || c == c1 || c == c2)
                    {
-                       if (paren) {
-                           if (n) {
-                               PL_regstartp[paren] = HOPc(PL_reginput, -1) - PL_bostr;
-                               PL_regendp[paren] = PL_reginput - PL_bostr;
-                           }
-                           else
-                               PL_regendp[paren] = -1;
-                       }
-                       if (regmatch(next))
-                           sayYES;
-                       REGCP_UNWIND;
+                       TRYPAREN(paren, n, PL_reginput);
+                       REGCP_UNWIND(lastcp);
                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;
@@ -2923,27 +3237,29 @@ S_regmatch(pTHX_ regnode *prog)
                n = regrepeat(scan, n);
                locinput = PL_reginput;
                if (ln < n && PL_regkind[(U8)OP(next)] == EOL &&
-                   (!PL_multiline  || OP(next) == SEOL))
+                   (!PL_multiline  || OP(next) == SEOL || OP(next) == EOS)) {
                    ln = n;                     /* why back off? */
-               REGCP_SET;
+                   /* ...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--;
+               }
+               REGCP_SET(lastcp);
                if (paren) {
+                   UV c;
                    while (n >= ln) {
+                       if (c1 != -1000) {
+                           if (do_utf8)
+                               c = utf8_to_uv_simple((U8*)PL_reginput, NULL);
+                           else
+                               c = UCHARAT(PL_reginput); 
+                       }
                        /* If it could work, try it. */
-                       if (c1 == -1000 ||
-                           UCHARAT(PL_reginput) == c1 ||
-                           UCHARAT(PL_reginput) == c2)
+                       if (c1 == -1000 || c == c1 || c == c2)
                            {
-                               if (paren && n) {
-                                   if (n) {
-                                       PL_regstartp[paren] = HOPc(PL_reginput, -1) - PL_bostr;
-                                       PL_regendp[paren] = PL_reginput - PL_bostr;
-                                   }
-                                   else
-                                       PL_regendp[paren] = -1;
-                               }
-                               if (regmatch(next))
-                                   sayYES;
-                               REGCP_UNWIND;
+                               TRYPAREN(paren, n, PL_reginput);
+                               REGCP_UNWIND(lastcp);
                            }
                        /* Couldn't or didn't -- back up. */
                        n--;
@@ -2951,15 +3267,19 @@ S_regmatch(pTHX_ regnode *prog)
                    }
                }
                else {
+                   UV c;
                    while (n >= ln) {
+                       if (c1 != -1000) {
+                           if (do_utf8)
+                               c = utf8_to_uv_simple((U8*)PL_reginput, NULL);
+                           else
+                               c = UCHARAT(PL_reginput); 
+                       }
                        /* If it could work, try it. */
-                       if (c1 == -1000 ||
-                           UCHARAT(PL_reginput) == c1 ||
-                           UCHARAT(PL_reginput) == c2)
+                       if (c1 == -1000 || c == c1 || c == c2)
                            {
-                               if (regmatch(next))
-                                   sayYES;
-                               REGCP_UNWIND;
+                               TRYPAREN(paren, n, PL_reginput);
+                               REGCP_UNWIND(lastcp);
                            }
                        /* Couldn't or didn't -- back up. */
                        n--;
@@ -2977,7 +3297,7 @@ S_regmatch(pTHX_ regnode *prog)
                CHECKPOINT cp, lastcp;
                
                cp = regcppush(0);      /* Save *all* the positions. */
-               REGCP_SET;
+               REGCP_SET(lastcp);
                regcp_set_to(PL_reg_call_cc->ss); /* Restore parens of
                                                    the caller. */
                PL_reginput = locinput; /* Make position available to
@@ -2990,7 +3310,7 @@ S_regmatch(pTHX_ regnode *prog)
                    regcpblow(cp);
                    sayYES;
                }
-               REGCP_UNWIND;
+               REGCP_UNWIND(lastcp);
                regcppop();
                PL_reg_call_cc = cur_call_cc;
                PL_regcc = cctmp;
@@ -3097,6 +3417,7 @@ S_regmatch(pTHX_ regnode *prog)
                          PTR2UV(scan), OP(scan));
            Perl_croak(aTHX_ "regexp memory corruption");
        }
+      reenter:
        scan = next;
     }
 
@@ -3122,6 +3443,11 @@ yes:
 #ifdef DEBUGGING
     PL_regindent--;
 #endif
+
+#if 0                                  /* Breaks $^R */
+    if (unwind)
+       regcpblow(firstcp);
+#endif
     return 1;
 
 no:
@@ -3133,6 +3459,55 @@ no:
     goto do_no;
 no_final:
 do_no:
+    if (unwind) {
+       re_unwind_t *uw = SSPTRt(unwind,re_unwind_t);
+
+       switch (uw->type) {
+       case RE_UNWIND_BRANCH:
+       case RE_UNWIND_BRANCHJ:
+       {
+           re_unwind_branch_t *uwb = &(uw->branch);
+           I32 lastparen = uwb->lastparen;
+           
+           REGCP_UNWIND(uwb->lastcp);
+           for (n = *PL_reglastparen; n > lastparen; n--)
+               PL_regendp[n] = -1;
+           *PL_reglastparen = n;
+           scan = next = uwb->next;
+           if ( !scan || 
+                OP(scan) != (uwb->type == RE_UNWIND_BRANCH 
+                             ? BRANCH : BRANCHJ) ) {           /* Failure */
+               unwind = uwb->prev;
+#ifdef DEBUGGING
+               PL_regindent--;
+#endif
+               goto do_no;
+           }
+           /* Have more choice yet.  Reuse the same uwb.  */
+           /*SUPPRESS 560*/
+           if ((n = (uwb->type == RE_UNWIND_BRANCH
+                     ? NEXT_OFF(next) : ARG(next))))
+               next += n;
+           else
+               next = NULL;    /* XXXX Needn't unwinding in this case... */
+           uwb->next = next;
+           next = NEXTOPER(scan);
+           if (uwb->type == RE_UNWIND_BRANCHJ)
+               next = NEXTOPER(next);
+           locinput = uwb->locinput;
+           nextchr = uwb->nextchr;
+#ifdef DEBUGGING
+           PL_regindent = uwb->regindent;
+#endif
+
+           goto reenter;
+       }
+       /* NOT REACHED */
+       default:
+           Perl_croak(aTHX_ "regexp unwind memory corruption");
+       }
+       /* NOT REACHED */
+    }
 #ifdef DEBUGGING
     PL_regindent--;
 #endif
@@ -3150,35 +3525,37 @@ do_no:
 STATIC I32
 S_regrepeat(pTHX_ regnode *p, I32 max)
 {
-    dTHR;
     register char *scan;
     register I32 c;
     register char *loceol = PL_regeol;
     register I32 hardcount = 0;
+    register bool do_utf8 = DO_UTF8(PL_reg_sv);
 
     scan = PL_reginput;
     if (max != REG_INFTY && max < loceol - scan)
       loceol = scan + max;
     switch (OP(p)) {
     case REG_ANY:
-       while (scan < loceol && *scan != '\n')
-           scan++;
-       break;
-    case SANY:
-       scan = loceol;
-       break;
-    case ANYUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && *scan != '\n') {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (scan < loceol && hardcount < max && *scan != '\n') {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && *scan != '\n')
+               scan++;
        }
        break;
-    case SANYUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+    case SANY:
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           scan = loceol;
        }
        break;
     case EXACT:                /* length of string is 1 */
@@ -3199,135 +3576,151 @@ S_regrepeat(pTHX_ regnode *p, I32 max)
               (UCHARAT(scan) == c || UCHARAT(scan) == PL_fold_locale[c]))
            scan++;
        break;
-    case ANYOFUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && REGINCLASSUTF8(p, (U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
-       }
-       break;
     case ANYOF:
-       while (scan < loceol && REGINCLASS(p, *scan))
-           scan++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  reginclass(p, (U8*)scan, do_utf8)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && reginclass(p, (U8*)scan, do_utf8))
+               scan++;
+       }
        break;
     case ALNUM:
-       while (scan < loceol && isALNUM(*scan))
-           scan++;
-       break;
-    case ALNUMUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && swash_fetch(PL_utf8_alnum, (U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  swash_fetch(PL_utf8_alnum, (U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && isALNUM(*scan))
+               scan++;
        }
        break;
     case ALNUML:
        PL_reg_flags |= RF_tainted;
-       while (scan < loceol && isALNUM_LC(*scan))
-           scan++;
-       break;
-    case ALNUMLUTF8:
-       PL_reg_flags |= RF_tainted;
-       loceol = PL_regeol;
-       while (scan < loceol && isALNUM_LC_utf8((U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  isALNUM_LC_utf8((U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && isALNUM_LC(*scan))
+               scan++;
        }
        break;
-       break;
     case NALNUM:
-       while (scan < loceol && !isALNUM(*scan))
-           scan++;
-       break;
-    case NALNUMUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && !swash_fetch(PL_utf8_alnum, (U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  !swash_fetch(PL_utf8_alnum, (U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && !isALNUM(*scan))
+               scan++;
        }
        break;
     case NALNUML:
        PL_reg_flags |= RF_tainted;
-       while (scan < loceol && !isALNUM_LC(*scan))
-           scan++;
-       break;
-    case NALNUMLUTF8:
-       PL_reg_flags |= RF_tainted;
-       loceol = PL_regeol;
-       while (scan < loceol && !isALNUM_LC_utf8((U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  !isALNUM_LC_utf8((U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && !isALNUM_LC(*scan))
+               scan++;
        }
        break;
     case SPACE:
-       while (scan < loceol && isSPACE(*scan))
-           scan++;
-       break;
-    case SPACEUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && (*scan == ' ' || swash_fetch(PL_utf8_space,(U8*)scan))) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  (*scan == ' ' || swash_fetch(PL_utf8_space,(U8*)scan))) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && isSPACE(*scan))
+               scan++;
        }
        break;
     case SPACEL:
        PL_reg_flags |= RF_tainted;
-       while (scan < loceol && isSPACE_LC(*scan))
-           scan++;
-       break;
-    case SPACELUTF8:
-       PL_reg_flags |= RF_tainted;
-       loceol = PL_regeol;
-       while (scan < loceol && (*scan == ' ' || isSPACE_LC_utf8((U8*)scan))) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  (*scan == ' ' || isSPACE_LC_utf8((U8*)scan))) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && isSPACE_LC(*scan))
+               scan++;
        }
        break;
     case NSPACE:
-       while (scan < loceol && !isSPACE(*scan))
-           scan++;
-       break;
-    case NSPACEUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && !(*scan == ' ' || swash_fetch(PL_utf8_space,(U8*)scan))) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  !(*scan == ' ' || swash_fetch(PL_utf8_space,(U8*)scan))) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && !isSPACE(*scan))
+               scan++;
+           break;
        }
-       break;
     case NSPACEL:
        PL_reg_flags |= RF_tainted;
-       while (scan < loceol && !isSPACE_LC(*scan))
-           scan++;
-       break;
-    case NSPACELUTF8:
-       PL_reg_flags |= RF_tainted;
-       loceol = PL_regeol;
-       while (scan < loceol && !(*scan == ' ' || isSPACE_LC_utf8((U8*)scan))) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  !(*scan == ' ' || isSPACE_LC_utf8((U8*)scan))) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && !isSPACE_LC(*scan))
+               scan++;
        }
        break;
     case DIGIT:
-       while (scan < loceol && isDIGIT(*scan))
-           scan++;
-       break;
-    case DIGITUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && swash_fetch(PL_utf8_digit,(U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  swash_fetch(PL_utf8_digit,(U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && isDIGIT(*scan))
+               scan++;
        }
        break;
-       break;
     case NDIGIT:
-       while (scan < loceol && !isDIGIT(*scan))
-           scan++;
-       break;
-    case NDIGITUTF8:
-       loceol = PL_regeol;
-       while (scan < loceol && !swash_fetch(PL_utf8_digit,(U8*)scan)) {
-           scan += UTF8SKIP(scan);
-           hardcount++;
+       if (do_utf8) {
+           loceol = PL_regeol;
+           while (hardcount < max && scan < loceol &&
+                  !swash_fetch(PL_utf8_digit,(U8*)scan)) {
+               scan += UTF8SKIP(scan);
+               hardcount++;
+           }
+       } else {
+           while (scan < loceol && !isDIGIT(*scan))
+               scan++;
        }
        break;
     default:           /* Called on something of 0 width. */
@@ -3362,7 +3755,6 @@ S_regrepeat(pTHX_ regnode *p, I32 max)
 STATIC I32
 S_regrepeat_hard(pTHX_ regnode *p, I32 max, I32 *lp)
 {
-    dTHR;
     register char *scan;
     register char *start;
     register char *loceol = PL_regeol;
@@ -3373,7 +3765,7 @@ S_regrepeat_hard(pTHX_ regnode *p, I32 max, I32 *lp)
        return 0;
 
     start = PL_reginput;
-    if (UTF) {
+    if (DO_UTF8(PL_reg_sv)) {
        while (PL_reginput < loceol && (scan = PL_reginput, res = regmatch(p))) {
            if (!count++) {
                l = 0;
@@ -3407,93 +3799,141 @@ S_regrepeat_hard(pTHX_ regnode *p, I32 max, I32 *lp)
 }
 
 /*
- - reginclass - determine if a character falls into a character class
- */
+- regclass_swash - prepare the utf8 swash
+*/
 
-STATIC bool
-S_reginclass(pTHX_ register regnode *p, register I32 c)
+SV *
+Perl_regclass_swash(pTHX_ register regnode* node, bool doinit, SV** initsvp)
 {
-    dTHR;
-    char flags = ANYOF_FLAGS(p);
-    bool match = FALSE;
+    SV *sw = NULL;
+    SV *si = NULL;
 
-    c &= 0xFF;
-    if (ANYOF_BITMAP_TEST(p, c))
-       match = TRUE;
-    else if (flags & ANYOF_FOLD) {
-       I32 cf;
-       if (flags & ANYOF_LOCALE) {
-           PL_reg_flags |= RF_tainted;
-           cf = PL_fold_locale[c];
-       }
-       else
-           cf = PL_fold[c];
-       if (ANYOF_BITMAP_TEST(p, cf))
-           match = TRUE;
-    }
+    if (PL_regdata && PL_regdata->count) {
+       U32 n = ARG(node);
 
-    if (!match && (flags & ANYOF_CLASS)) {
-       PL_reg_flags |= RF_tainted;
-       if (
-           (ANYOF_CLASS_TEST(p, ANYOF_ALNUM)   &&  isALNUM_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NALNUM)  && !isALNUM_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_SPACE)   &&  isSPACE_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NSPACE)  && !isSPACE_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_DIGIT)   &&  isDIGIT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NDIGIT)  && !isDIGIT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_ALNUMC)  &&  isALNUMC_LC(c)) ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NALNUMC) && !isALNUMC_LC(c)) ||
-           (ANYOF_CLASS_TEST(p, ANYOF_ALPHA)   &&  isALPHA_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NALPHA)  && !isALPHA_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_ASCII)   &&  isASCII(c))     ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NASCII)  && !isASCII(c))     ||
-           (ANYOF_CLASS_TEST(p, ANYOF_CNTRL)   &&  isCNTRL_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NCNTRL)  && !isCNTRL_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_GRAPH)   &&  isGRAPH_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NGRAPH)  && !isGRAPH_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_LOWER)   &&  isLOWER_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NLOWER)  && !isLOWER_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_PRINT)   &&  isPRINT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NPRINT)  && !isPRINT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_PUNCT)   &&  isPUNCT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NPUNCT)  && !isPUNCT_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_UPPER)   &&  isUPPER_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NUPPER)  && !isUPPER_LC(c))  ||
-           (ANYOF_CLASS_TEST(p, ANYOF_XDIGIT)  &&  isXDIGIT(c))    ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NXDIGIT) && !isXDIGIT(c))
-           ) /* How's that for a conditional? */
-       {
-           match = TRUE;
+       if (PL_regdata->what[n] == 's') {
+           SV *rv = (SV*)PL_regdata->data[n];
+           AV *av = (AV*)SvRV((SV*)rv);
+           SV **a;
+           
+           si = *av_fetch(av, 0, FALSE);
+           a  =  av_fetch(av, 1, FALSE);
+           
+           if (a)
+               sw = *a;
+           else if (si && doinit) {
+               sw = swash_init("utf8", "", si, 1, 0);
+               (void)av_store(av, 1, sw);
+           }
        }
     }
+       
+    if (initsvp)
+       *initsvp = si;
 
-    return (flags & ANYOF_INVERT) ? !match : match;
+    return sw;
 }
 
+/*
+ - reginclass - determine if a character falls into a character class
+ */
+
 STATIC bool
-S_reginclassutf8(pTHX_ regnode *f, U8 *p)
-{                                           
-    dTHR;
-    char flags = ARG1(f);
+S_reginclass(pTHX_ register regnode *n, register U8* p, register bool do_utf8)
+{
+    char flags = ANYOF_FLAGS(n);
     bool match = FALSE;
-    SV *sv = (SV*)PL_regdata->data[ARG2(f)];
-
-    if (swash_fetch(sv, p))
-       match = TRUE;
-    else if (flags & ANYOF_FOLD) {
-       I32 cf;
-       U8 tmpbuf[10];
-       if (flags & ANYOF_LOCALE) {
-           PL_reg_flags |= RF_tainted;
-           uv_to_utf8(tmpbuf, toLOWER_LC_utf8(p));
+    UV c;
+    STRLEN len;
+
+    if (do_utf8)
+       c = utf8_to_uv_simple(p, &len);
+    else
+       c = *p;
+
+    if (do_utf8 || (flags & ANYOF_UNICODE)) {
+       if (do_utf8 && !ANYOF_RUNTIME(n)) {
+           if (len != (STRLEN)-1 && c < 256 && ANYOF_BITMAP_TEST(n, c))
+               match = TRUE;
        }
-       else
-           uv_to_utf8(tmpbuf, toLOWER_utf8(p));
-       if (swash_fetch(sv, tmpbuf))
+       if (do_utf8 && flags & ANYOF_UNICODE_ALL && c >= 256)
            match = TRUE;
+       if (!match) {
+           SV *sw = regclass_swash(n, TRUE, 0);
+       
+           if (sw) {
+               if (swash_fetch(sw, p))
+                   match = TRUE;
+               else if (flags & ANYOF_FOLD) {
+                   U8 tmpbuf[UTF8_MAXLEN+1];
+                   
+                   if (flags & ANYOF_LOCALE) {
+                       PL_reg_flags |= RF_tainted;
+                       uv_to_utf8(tmpbuf, toLOWER_LC_utf8(p));
+                   }
+                   else
+                       uv_to_utf8(tmpbuf, toLOWER_utf8(p));
+                   if (swash_fetch(sw, tmpbuf))
+                       match = TRUE;
+               }
+           }
+       }
     }
+    if (!match && c < 256) {
+       if (ANYOF_BITMAP_TEST(n, c))
+           match = TRUE;
+       else if (flags & ANYOF_FOLD) {
+           I32 f;
 
-    /* UTF8 combined with ANYOF_CLASS is ill-defined. */
+           if (flags & ANYOF_LOCALE) {
+               PL_reg_flags |= RF_tainted;
+               f = PL_fold_locale[c];
+           }
+           else
+               f = PL_fold[c];
+           if (f != c && ANYOF_BITMAP_TEST(n, f))
+               match = TRUE;
+       }
+       
+       if (!match && (flags & ANYOF_CLASS)) {
+           PL_reg_flags |= RF_tainted;
+           if (
+               (ANYOF_CLASS_TEST(n, ANYOF_ALNUM)   &&  isALNUM_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NALNUM)  && !isALNUM_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_SPACE)   &&  isSPACE_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NSPACE)  && !isSPACE_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_DIGIT)   &&  isDIGIT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NDIGIT)  && !isDIGIT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_ALNUMC)  &&  isALNUMC_LC(c)) ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NALNUMC) && !isALNUMC_LC(c)) ||
+               (ANYOF_CLASS_TEST(n, ANYOF_ALPHA)   &&  isALPHA_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NALPHA)  && !isALPHA_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_ASCII)   &&  isASCII(c))     ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NASCII)  && !isASCII(c))     ||
+               (ANYOF_CLASS_TEST(n, ANYOF_CNTRL)   &&  isCNTRL_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NCNTRL)  && !isCNTRL_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_GRAPH)   &&  isGRAPH_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NGRAPH)  && !isGRAPH_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_LOWER)   &&  isLOWER_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NLOWER)  && !isLOWER_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_PRINT)   &&  isPRINT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NPRINT)  && !isPRINT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_PUNCT)   &&  isPUNCT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NPUNCT)  && !isPUNCT_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_UPPER)   &&  isUPPER_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NUPPER)  && !isUPPER_LC(c))  ||
+               (ANYOF_CLASS_TEST(n, ANYOF_XDIGIT)  &&  isXDIGIT(c))    ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NXDIGIT) && !isXDIGIT(c))    ||
+               (ANYOF_CLASS_TEST(n, ANYOF_PSXSPC)  &&  isPSXSPC(c))    ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NPSXSPC) && !isPSXSPC(c))    ||
+               (ANYOF_CLASS_TEST(n, ANYOF_BLANK)   &&  isBLANK(c))     ||
+               (ANYOF_CLASS_TEST(n, ANYOF_NBLANK)  && !isBLANK(c))
+               ) /* How's that for a conditional? */
+           {
+               match = TRUE;
+           }
+       }
+    }
 
     return (flags & ANYOF_INVERT) ? !match : match;
 }
@@ -3501,19 +3941,27 @@ S_reginclassutf8(pTHX_ regnode *f, U8 *p)
 STATIC U8 *
 S_reghop(pTHX_ U8 *s, I32 off)
 {                               
-    dTHR;
+    return S_reghop3(aTHX_ s, off, (U8*)(off >= 0 ? PL_regeol : PL_bostr));
+}
+
+STATIC U8 *
+S_reghop3(pTHX_ U8 *s, I32 off, U8* lim)
+{                               
     if (off >= 0) {
-       while (off-- && s < (U8*)PL_regeol)
+       while (off-- && s < lim) {
+           /* XXX could check well-formedness here */
            s += UTF8SKIP(s);
+       }
     }
     else {
        while (off++) {
-           if (s > (U8*)PL_bostr) {
+           if (s > lim) {
                s--;
-               if (*s & 0x80) {
-                   while (s > (U8*)PL_bostr && (*s & 0xc0) == 0x80)
+               if (UTF8_IS_CONTINUED(*s)) {
+                   while (s > (U8*)lim && UTF8_IS_CONTINUATION(*s))
                        s--;
-               }               /* XXX could check well-formedness here */
+               }
+               /* XXX could check well-formedness here */
            }
        }
     }
@@ -3521,23 +3969,31 @@ S_reghop(pTHX_ U8 *s, I32 off)
 }
 
 STATIC U8 *
-S_reghopmaybe(pTHX_ U8* s, I32 off)
+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)
 {
-    dTHR;
     if (off >= 0) {
-       while (off-- && s < (U8*)PL_regeol)
+       while (off-- && s < lim) {
+           /* XXX could check well-formedness here */
            s += UTF8SKIP(s);
+       }
        if (off >= 0)
            return 0;
     }
     else {
        while (off++) {
-           if (s > (U8*)PL_bostr) {
+           if (s > lim) {
                s--;
-               if (*s & 0x80) {
-                   while (s > (U8*)PL_bostr && (*s & 0xc0) == 0x80)
+               if (UTF8_IS_CONTINUED(*s)) {
+                   while (s > (U8*)lim && UTF8_IS_CONTINUATION(*s))
                        s--;
-               }               /* XXX could check well-formedness here */
+               }
+               /* XXX could check well-formedness here */
            }
            else
                break;
@@ -3555,7 +4011,6 @@ S_reghopmaybe(pTHX_ U8* s, I32 off)
 static void
 restore_pos(pTHXo_ void *arg)
 {
-    dTHR;
     if (PL_reg_eval_set) {
        if (PL_reg_oldsaved) {
            PL_reg_re->subbeg = PL_reg_oldsaved;
@@ -3567,4 +4022,3 @@ restore_pos(pTHXo_ void *arg)
        PL_curpm = PL_reg_oldcurpm;
     }  
 }
-