This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Lost chunk of RE jumbo patch
[perl5.git] / regexec.c
index 271dc4d..ac9f37b 100644 (file)
--- a/regexec.c
+++ b/regexec.c
 #include "perl.h"
 #include "regcomp.h"
 
+#define RF_tainted     1               /* tainted information used? */
+#define RF_warned      2               /* warned about big count? */
+#define RF_evaled      4               /* Did an EVAL? */
+
 #ifndef STATIC
 #define        STATIC  static
 #endif
 
-#ifdef DEBUGGING
-static I32 regnarrate = 0;
-static char* regprogram = 0;
-#endif
+#ifndef PERL_OBJECT
+typedef I32 CHECKPOINT;
 
-/* Current curly descriptor */
-typedef struct curcur CURCUR;
-struct curcur {
-    int                parenfloor;     /* how far back to strip paren data */
-    int                cur;            /* how many instances of scan we've matched */
-    int                min;            /* the minimal number of scans to match */
-    int                max;            /* the maximal number of scans to match */
-    int                minmod;         /* whether to work our way up or down */
-    char *     scan;           /* the thing to match */
-    char *     next;           /* what has to match after it */
-    char *     lastloc;        /* where we started matching this scan */
-    CURCUR *   oldcc;          /* current curly before we started this one */
-};
-
-static CURCUR* regcc;
+/*
+ * Forwards.
+ */
 
-typedef I32 CHECKPOINT;
+static I32 regmatch _((regnode *prog));
+static I32 regrepeat _((regnode *p, I32 max));
+static I32 regrepeat_hard _((regnode *p, I32 max, I32 *lp));
+static I32 regtry _((regexp *prog, char *startpos));
 
+static bool reginclass _((char *p, I32 c));
 static CHECKPOINT regcppush _((I32 parenfloor));
 static char * regcppop _((void));
+#endif
+#define REGINCLASS(p,c)  (*(p) ? reginclass(p,c) : ANYOF_TEST(p,c))
 
-static CHECKPOINT
-regcppush(parenfloor)
-I32 parenfloor;
+STATIC CHECKPOINT
+regcppush(I32 parenfloor)
 {
+    dTHR;
     int retval = savestack_ix;
-    int i = (regsize - parenfloor) * 3;
+    int i = (regsize - parenfloor) * 4;
     int p;
 
     SSCHECK(i + 5);
     for (p = regsize; p > parenfloor; p--) {
        SSPUSHPTR(regendp[p]);
        SSPUSHPTR(regstartp[p]);
+       SSPUSHPTR(reg_start_tmp[p]);
        SSPUSHINT(p);
     }
     SSPUSHINT(regsize);
@@ -107,9 +104,14 @@ I32 parenfloor;
     return retval;
 }
 
-static char *
-regcppop()
+/* 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", savestack_ix)); lastcp = savestack_ix
+#  define REGCP_UNWIND  DEBUG_r(lastcp != savestack_ix ? PerlIO_printf(Perl_debug_log,"  Clearing an EVAL scope, savestack=%i..%i\n", lastcp, savestack_ix) : 0); regcpblow(lastcp)
+
+STATIC char *
+regcppop(void)
 {
+    dTHR;
     I32 i = SSPOPINT;
     U32 paren = 0;
     char *input;
@@ -119,13 +121,27 @@ regcppop()
     input = (char *) SSPOPPTR;
     *reglastparen = SSPOPINT;
     regsize = SSPOPINT;
-    for (i -= 3; i > 0; i -= 3) {
+    for (i -= 3; i > 0; i -= 4) {
        paren = (U32)SSPOPINT;
+       reg_start_tmp[paren] = (char *) SSPOPPTR;
        regstartp[paren] = (char *) SSPOPPTR;
        tmps = (char*)SSPOPPTR;
        if (paren <= *reglastparen)
            regendp[paren] = tmps;
+       DEBUG_r(
+           PerlIO_printf(Perl_debug_log, "     restoring \\%d to %d(%d)..%d%s\n",
+                         paren, regstartp[paren] - regbol, 
+                         reg_start_tmp[paren] - regbol,
+                         regendp[paren] - regbol, 
+                         (paren > *reglastparen ? "(no)" : ""));
+       );
     }
+    DEBUG_r(
+       if (*reglastparen + 1 <= regnpar) {
+           PerlIO_printf(Perl_debug_log, "     restoring \\%d..\\%d to undef\n",
+                         *reglastparen + 1, regnpar);
+       }
+    );
     for (paren = *reglastparen + 1; paren <= regnpar; paren++) {
        if (paren > regsize)
            regstartp[paren] = Nullch;
@@ -134,76 +150,56 @@ regcppop()
     return input;
 }
 
-/* After a successful match in WHILEM, we want to restore paren matches
- * that have been overwritten by a failed match attempt in the process
- * of reaching this success. We do this by restoring regstartp[i]
- * wherever regendp[i] has not changed; if OPEN is changed to modify
- * regendp[], the '== endp' test below should be changed to match.
- * This corrects the error of:
- *     0 > length [ "foobar" =~ / ( (foo) | (bar) )* /x ]->[1]
- */
-static void
-regcppartblow()
-{
-    I32 i = SSPOPINT;
-    U32 paren;
-    char *startp;
-    char *endp;
-    assert(i == SAVEt_REGCONTEXT);
-    i = SSPOPINT;
-    /* input, lastparen, size */
-    SSPOPPTR; SSPOPINT; SSPOPINT;
-    for (i -= 3; i > 0; i -= 3) {
-       paren = (U32)SSPOPINT;
-       startp = (char *) SSPOPPTR;
-       endp = (char *) SSPOPPTR;
-       if (paren <= *reglastparen && regendp[paren] == endp)
-           regstartp[paren] = startp;
-    }
-}
-
-#define regcpblow(cp) leave_scope(cp)
+#define regcpblow(cp) LEAVE_SCOPE(cp)
 
 /*
  * pregexec and friends
  */
 
 /*
- * Forwards.
+ - pregexec - match a regexp against a string
  */
-
-static I32 regmatch _((char *prog));
-static I32 regrepeat _((char *p, I32 max));
-static I32 regtry _((regexp *prog, char *startpos));
-static bool reginclass _((char *p, I32 c));
-
-static bool regtainted;                /* tainted information used? */
-
+I32
+pregexec(register regexp *prog, char *stringarg, register char *strend, char *strbeg, I32 minend, SV *screamer, U32 nosave)
+/* strend: pointer to null at end of string */
+/* strbeg: real beginning of string */
+/* minend: end of match must be >=minend after stringarg. */
+/* nosave: For optimizations. */
+{
+    return
+       regexec_flags(prog, stringarg, strend, strbeg, minend, screamer, NULL, 
+                     nosave ? 0 : REXEC_COPY_STR);
+}
+  
 /*
- - pregexec - match a regexp against a string
+ - regexec_flags - match a regexp against a string
  */
 I32
-pregexec(prog, stringarg, strend, strbeg, minend, screamer, safebase)
-register regexp *prog;
-char *stringarg;
-register char *strend; /* pointer to null at end of string */
-char *strbeg;  /* real beginning of string */
-I32 minend;    /* end of match must be at least minend after stringarg */
-SV *screamer;
-I32 safebase;  /* no need to remember string in subbase */
+regexec_flags(register regexp *prog, char *stringarg, register char *strend, char *strbeg, I32 minend, SV *screamer, 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 char *c;
+    register regnode *c;
     register char *startpos = stringarg;
     register I32 tmp;
-    I32 minlen = 0;            /* must match at least this many chars */
+    I32 minlen;                /* must match at least this many chars */
     I32 dontbother = 0;        /* how many characters not to try at end */
     CURCUR cc;
+    I32 start_shift = 0;               /* Offset of the start to find
+                                        constant substr. */
+    I32 end_shift = 0;                 /* Same for the end. */
+    I32 scream_pos = -1;               /* Internal iterator of scream. */
+    char *scream_olds;
 
     cc.cur = 0;
     cc.oldcc = 0;
     regcc = &cc;
 
+    regprecomp = prog->precomp;                /* Needed for error messages. */
 #ifdef DEBUGGING
     regnarrate = debug & 512;
     regprogram = prog->program;
@@ -215,6 +211,9 @@ I32 safebase;       /* no need to remember string in subbase */
        return 0;
     }
 
+    minlen = prog->minlen;
+    if (strend - startpos < minlen) goto phooey;
+
     if (startpos == strbeg)    /* is ^ valid at stringarg? */
        regprev = '\n';
     else {
@@ -223,54 +222,58 @@ I32 safebase;     /* no need to remember string in subbase */
            regprev = '\0';             /* force ^ to NOT match */
     }
 
-    regprecomp = prog->precomp;
     /* Check validity of program. */
     if (UCHARAT(prog->program) != MAGIC) {
        FAIL("corrupted regexp program");
     }
 
     regnpar = prog->nparens;
-    regtainted = FALSE;
+    reg_flags = 0;
+    reg_eval_set = 0;
 
     /* If there is a "must appear" string, look for it. */
     s = startpos;
-    if (prog->regmust != Nullsv &&
+    if (!(flags & REXEC_CHECKED) 
+       && prog->check_substr != Nullsv &&
        !(prog->reganch & ROPT_ANCH_GPOS) &&
-       (!(prog->reganch & ROPT_ANCH_BOL)
-        || (multiline && prog->regback >= 0)) )
+       (!(prog->reganch & (ROPT_ANCH_BOL | ROPT_ANCH_MBOL))
+        || (multiline && prog->check_substr == prog->anchored_substr)) )
     {
-       if (stringarg == strbeg && screamer) {
-           if (screamfirst[BmRARE(prog->regmust)] >= 0)
-                   s = screaminstr(screamer,prog->regmust);
+       start_shift = prog->check_offset_min;
+       /* Should be nonnegative! */
+       end_shift = minlen - start_shift - SvCUR(prog->check_substr);
+       if (screamer) {
+           if (screamfirst[BmRARE(prog->check_substr)] >= 0)
+                   s = screaminstr(screamer, prog->check_substr, 
+                                   start_shift + (stringarg - strbeg),
+                                   end_shift, &scream_pos, 0);
            else
                    s = Nullch;
+           scream_olds = s;
        }
        else
-           s = fbm_instr((unsigned char*)s, (unsigned char*)strend,
-               prog->regmust);
+           s = fbm_instr((unsigned char*)s + start_shift,
+                         (unsigned char*)strend - end_shift,
+               prog->check_substr);
        if (!s) {
-           ++BmUSEFUL(prog->regmust);  /* hooray */
+           ++BmUSEFUL(prog->check_substr);     /* hooray */
            goto phooey;        /* not present */
-       }
-       else if (prog->regback >= 0) {
-           s -= prog->regback;
-           if (s < startpos)
-               s = startpos;
-           minlen = prog->regback + SvCUR(prog->regmust);
-       }
-       else if (!prog->naughty && --BmUSEFUL(prog->regmust) < 0) { /* boo */
-           SvREFCNT_dec(prog->regmust);
-           prog->regmust = Nullsv;     /* disable regmust */
+       } else if ((s - stringarg) > prog->check_offset_max) {
+           ++BmUSEFUL(prog->check_substr);     /* hooray/2 */
+           s -= prog->check_offset_max;
+       } else if (!prog->naughty 
+                  && --BmUSEFUL(prog->check_substr) < 0
+                  && prog->check_substr == prog->float_substr) { /* boo */
+           SvREFCNT_dec(prog->check_substr);
+           prog->check_substr = Nullsv;        /* disable */
+           prog->float_substr = Nullsv;        /* clear */
            s = startpos;
-       }
-       else {
-           s = startpos;
-           minlen = SvCUR(prog->regmust);
-       }
+       } else s = startpos;
     }
 
-    /* Mark beginning of line for ^ . */
+    /* Mark beginning of line for ^ and lookbehind. */
     regbol = startpos;
+    bostr  = strbeg;
 
     /* Mark end of line for $ (and such) */
     regeol = strend;
@@ -278,13 +281,24 @@ I32 safebase;     /* no need to remember string in subbase */
     /* see how far we have to get to not match where we matched before */
     regtill = startpos+minend;
 
+    DEBUG_r(
+       PerlIO_printf(Perl_debug_log, 
+                     "Matching `%.60s%s' against `%.*s%s'\n",
+                     prog->precomp, 
+                     (strlen(prog->precomp) > 60 ? "..." : ""),
+                     (strend - startpos > 60 ? 60 : strend - startpos),
+                     startpos, 
+                     (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) {
        if (regtry(prog, startpos))
            goto got_it;
        else if (!(prog->reganch & ROPT_ANCH_GPOS) &&
-                (multiline || (prog->reganch & ROPT_IMPLICIT)))
+                (multiline || (prog->reganch & ROPT_IMPLICIT)
+                 || (prog->reganch & ROPT_ANCH_MBOL)))
        {
            if (minlen)
                dontbother = minlen - 1;
@@ -303,45 +317,64 @@ I32 safebase;     /* no need to remember string in subbase */
     }
 
     /* Messy cases:  unanchored match. */
-    if (prog->regstart) {
-       if (prog->reganch & ROPT_SKIP) {  /* we have /x+whatever/ */
-           /* it must be a one character string */
-           char ch = SvPVX(prog->regstart)[0];
-           while (s < strend) {
-               if (*s == ch) {
-                   if (regtry(prog, s))
-                       goto got_it;
-                   s++;
-                   while (s < strend && *s == ch)
-                       s++;
-               }
+    if (prog->anchored_substr && prog->reganch & ROPT_SKIP) { 
+       /* we have /x+whatever/ */
+       /* it must be a one character string */
+       char ch = SvPVX(prog->anchored_substr)[0];
+       while (s < strend) {
+           if (*s == ch) {
+               if (regtry(prog, s)) goto got_it;
                s++;
+               while (s < strend && *s == ch)
+                   s++;
            }
+           s++;
        }
-       else if (SvTYPE(prog->regstart) == SVt_PVBM) {
-           /* We know what string it must start with. */
-           while ((s = fbm_instr((unsigned char*)s,
-             (unsigned char*)strend, prog->regstart)) != NULL)
-           {
-               if (regtry(prog, s))
-                   goto got_it;
-               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 = strend - SvCUR(must) - back_min; /* Cannot start after this */
+       char *last1 = s - 1;            /* Last position checked before */
+
+       /* XXXX check_substr already used to find `s', can optimize if
+          check_substr==must. */
+       scream_pos = -1;
+       dontbother = end_shift;
+       strend -= dontbother;
+       while ( (s <= last) &&
+               (screamer 
+                ? (s = screaminstr(screamer, must, s + back_min - strbeg,
+                                   end_shift, &scream_pos, 0))
+                : (s = fbm_instr((unsigned char*)s + back_min,
+                                 (unsigned char*)strend, must))) ) {
+           if (s - back_max > last1) {
+               last1 = s - back_min;
+               s = s - back_max;
+           } else {
+               char *t = last1 + 1;            
+
+               last1 = s - back_min;
+               s = t;          
            }
-       }
-       else {                          /* Optimized fbm_instr: */
-           c = SvPVX(prog->regstart);
-           while ((s = ninstr(s, strend, c, c + SvCUR(prog->regstart))) != NULL)
-           {
+           while (s <= last1) {
                if (regtry(prog, s))
                    goto got_it;
                s++;
            }
        }
        goto phooey;
-    }
-    /*SUPPRESS 560*/
-    if (c = prog->regstclass) {
+    } else if (c = prog->regstclass) {
        I32 doevery = (prog->reganch & ROPT_SKIP) == 0;
+       char *Class;
 
        if (minlen)
            dontbother = minlen - 1;
@@ -350,9 +383,9 @@ I32 safebase;       /* no need to remember string in subbase */
        /* We know what class it must start with. */
        switch (OP(c)) {
        case ANYOF:
-           c = OPERAND(c);
+           Class = (char *) OPERAND(c);
            while (s < strend) {
-               if (reginclass(c, *s)) {
+               if (REGINCLASS(Class, *s)) {
                    if (tmp && regtry(prog, s))
                        goto got_it;
                    else
@@ -364,7 +397,7 @@ I32 safebase;       /* no need to remember string in subbase */
            }
            break;
        case BOUNDL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case BOUND:
            if (minlen)
@@ -383,7 +416,7 @@ I32 safebase;       /* no need to remember string in subbase */
                goto got_it;
            break;
        case NBOUNDL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NBOUND:
            if (minlen)
@@ -414,7 +447,7 @@ I32 safebase;       /* no need to remember string in subbase */
            }
            break;
        case ALNUML:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            while (s < strend) {
                if (isALNUM_LC(*s)) {
                    if (tmp && regtry(prog, s))
@@ -441,7 +474,7 @@ I32 safebase;       /* no need to remember string in subbase */
            }
            break;
        case NALNUML:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            while (s < strend) {
                if (!isALNUM_LC(*s)) {
                    if (tmp && regtry(prog, s))
@@ -468,7 +501,7 @@ I32 safebase;       /* no need to remember string in subbase */
            }
            break;
        case SPACEL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            while (s < strend) {
                if (isSPACE_LC(*s)) {
                    if (tmp && regtry(prog, s))
@@ -495,7 +528,7 @@ I32 safebase;       /* no need to remember string in subbase */
            }
            break;
        case NSPACEL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            while (s < strend) {
                if (!isSPACE_LC(*s)) {
                    if (tmp && regtry(prog, s))
@@ -537,7 +570,26 @@ I32 safebase;      /* no need to remember string in subbase */
        }
     }
     else {
-       if (minlen)
+       dontbother = 0;
+       if (prog->float_substr != Nullsv) {     /* Trim the end. */
+           char *last;
+           I32 oldpos = scream_pos;
+
+           if (screamer) {
+               last = screaminstr(screamer, prog->float_substr, s - strbeg,
+                                  end_shift, &scream_pos, 1); /* last one */
+               if (!last) {
+                   last = scream_olds; /* Only one occurence. */
+               }
+           } else {
+               STRLEN len;
+               char *little = SvPV(prog->float_substr, len);
+               last = rninstr(s, strend, little, little + len);
+           }
+           if (last == NULL) goto phooey; /* Should not happen! */
+           dontbother = strend - last - 1;
+       }
+       if (minlen && (dontbother < minlen))
            dontbother = minlen - 1;
        strend -= dontbother;
        /* We don't know much -- general case. */
@@ -554,11 +606,11 @@ got_it:
     strend += dontbother;      /* uncheat */
     prog->subbeg = strbeg;
     prog->subend = strend;
-    prog->exec_tainted = regtainted;
+    RX_MATCH_TAINTED_SET(prog, reg_flags & RF_tainted);
 
     /* make sure $`, $&, $', and $digit will work later */
-    if (strbeg != prog->subbase) {
-       if (safebase) {
+    if (strbeg != prog->subbase) {     /* second+ //g match.  */
+       if (!(flags & REXEC_COPY_STR)) {
            if (prog->subbase) {
                Safefree(prog->subbase);
                prog->subbase = Nullch;
@@ -589,14 +641,14 @@ phooey:
 /*
  - regtry - try match at specific point
  */
-static I32                     /* 0 failure, 1 success */
-regtry(prog, startpos)
-regexp *prog;
-char *startpos;
+STATIC I32                     /* 0 failure, 1 success */
+regtry(regexp *prog, char *startpos)
 {
+    dTHR;
     register I32 i;
     register char **sp;
     register char **ep;
+    CHECKPOINT lastcp;
 
     reginput = startpos;
     regstartp = prog->startp;
@@ -604,22 +656,31 @@ char *startpos;
     reglastparen = &prog->lastparen;
     prog->lastparen = 0;
     regsize = 0;
+    if (reg_start_tmpl <= prog->nparens) {
+       reg_start_tmpl = prog->nparens*3/2 + 3;
+        if(reg_start_tmp)
+            Renew(reg_start_tmp, reg_start_tmpl, char*);
+        else
+            New(22,reg_start_tmp, reg_start_tmpl, char*);
+    }
 
     sp = prog->startp;
     ep = prog->endp;
+    regdata = prog->data;
     if (prog->nparens) {
        for (i = prog->nparens; i >= 0; i--) {
            *sp++ = NULL;
            *ep++ = NULL;
        }
     }
+    REGCP_SET;
     if (regmatch(prog->program + 1) && reginput >= regtill) {
        prog->startp[0] = startpos;
        prog->endp[0] = reginput;
        return 1;
     }
-    else
-       return 0;
+    REGCP_UNWIND;
+    return 0;
 }
 
 /*
@@ -636,46 +697,64 @@ char *startpos;
  * maybe save a little bit of pushing and popping on the stack.  It also takes
  * advantage of machines that use a register save mask on subroutine entry.
  */
-static I32                     /* 0 failure, 1 success */
-regmatch(prog)
-char *prog;
+STATIC I32                     /* 0 failure, 1 success */
+regmatch(regnode *prog)
 {
-    register char *scan;       /* Current node. */
-    char *next;                        /* Next node. */
-    register I32 nextchar;
+    dTHR;
+    register regnode *scan;    /* Current node. */
+    regnode *next;             /* Next node. */
+    regnode *inner;            /* Next node in internal branch. */
+    register I32 nextchr; /* renamed nextchr - nextchar colides with function of same name */
     register I32 n;            /* no or next */
     register I32 ln;           /* len or last */
     register char *s;          /* operand or save */
     register char *locinput = reginput;
-    register I32 c1, c2;       /* case fold search */
-    int minmod = 0;
+    register I32 c1, c2, paren;        /* case fold search, parenth */
+    int minmod = 0, sw = 0, logical = 0;
 #ifdef DEBUGGING
-    static int regindent = 0;
     regindent++;
 #endif
 
-    nextchar = UCHARAT(locinput);
+    nextchr = UCHARAT(locinput);
     scan = prog;
     while (scan != NULL) {
+#define sayNO_L (logical ? (logical = 0, sw = 0, goto cont) : sayNO)
 #ifdef DEBUGGING
-#define sayYES goto yes
-#define sayNO goto no
-#define saySAME(x) if (x) goto yes; else goto no
-       if (regnarrate) {
+#  define sayYES goto yes
+#  define sayNO goto no
+#  define saySAME(x) if (x) goto yes; else goto no
+#  define REPORT_CODE_OFF 24
+#else
+#  define sayYES return 1
+#  define sayNO return 0
+#  define saySAME(x) return x
+#endif
+       DEBUG_r( {
            SV *prop = sv_newmortal();
+           int docolor = *colors[0];
+           int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
+           int l = (regeol - locinput > taill ? taill : regeol - locinput);
+           int pref_len = (locinput - bostr > (5 + taill) - l 
+                           ? (5 + taill) - l : locinput - bostr);
+
+           if (l + pref_len < (5 + taill) && l < regeol - locinput)
+               l = ( regeol - locinput > (5 + taill) - pref_len 
+                     ? (5 + taill) - pref_len : regeol - locinput);
            regprop(prop, scan);
-           PerlIO_printf(Perl_debug_log, "%*s%2d%-8.8s\t<%.10s>\n",
+           PerlIO_printf(Perl_debug_log, 
+                         "%4i <%s%.*s%s%s%s%.*s%s>%*s|%*s%2d%s\n",
+                         locinput - bostr, 
+                         colors[2], pref_len, locinput - pref_len, colors[3],
+                         (docolor ? "" : "> <"),
+                         colors[0], l, locinput, colors[1],
+                         15 - l - pref_len + 1,
+                         "",
                          regindent*2, "", scan - regprogram,
-                         SvPVX(prop), locinput);
-       }
-#else
-#define sayYES return 1
-#define sayNO return 0
-#define saySAME(x) return x
-#endif
+                         SvPVX(prop));
+       } );
 
 #ifdef REGALIGN
-       next = scan + NEXT(scan);
+       next = scan + NEXT_OFF(scan);
        if (next == scan)
            next = NULL;
 #else
@@ -686,7 +765,8 @@ char *prog;
        case BOL:
            if (locinput == regbol
                ? regprev == '\n'
-               : ((nextchar || locinput < regeol) && locinput[-1] == '\n') )
+               : (multiline && 
+                  (nextchr || locinput < regeol) && locinput[-1] == '\n') )
            {
                /* regtill = regbol; */
                break;
@@ -695,7 +775,7 @@ char *prog;
        case MBOL:
            if (locinput == regbol
                ? regprev == '\n'
-               : ((nextchar || locinput < regeol) && locinput[-1] == '\n') )
+               : ((nextchr || locinput < regeol) && locinput[-1] == '\n') )
            {
                break;
            }
@@ -715,49 +795,49 @@ char *prog;
                goto seol;
        case MEOL:
          meol:
-           if ((nextchar || locinput < regeol) && nextchar != '\n')
+           if ((nextchr || locinput < regeol) && nextchr != '\n')
                sayNO;
            break;
        case SEOL:
          seol:
-           if ((nextchar || locinput < regeol) && nextchar != '\n')
+           if ((nextchr || locinput < regeol) && nextchr != '\n')
                sayNO;
            if (regeol - locinput > 1)
                sayNO;
            break;
        case SANY:
-           if (!nextchar && locinput >= regeol)
+           if (!nextchr && locinput >= regeol)
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case ANY:
-           if (!nextchar && locinput >= regeol || nextchar == '\n')
+           if (!nextchr && locinput >= regeol || nextchr == '\n')
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case EXACT:
-           s = OPERAND(scan);
-           ln = *s++;
+           s = (char *) OPERAND(scan);
+           ln = UCHARAT(s++);
            /* Inline the first character, for speed. */
-           if (UCHARAT(s) != nextchar)
+           if (UCHARAT(s) != nextchr)
                sayNO;
            if (regeol - locinput < ln)
                sayNO;
            if (ln > 1 && memNE(s, locinput, ln))
                sayNO;
            locinput += ln;
-           nextchar = UCHARAT(locinput);
+           nextchr = UCHARAT(locinput);
            break;
        case EXACTFL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case EXACTF:
-           s = OPERAND(scan);
-           ln = *s++;
+           s = (char *) OPERAND(scan);
+           ln = UCHARAT(s++);
            /* Inline the first character, for speed. */
-           if (UCHARAT(s) != nextchar &&
+           if (UCHARAT(s) != nextchr &&
                UCHARAT(s) != ((OP(scan) == EXACTF)
-                              ? fold : fold_locale)[nextchar])
+                              ? fold : fold_locale)[nextchr])
                sayNO;
            if (regeol - locinput < ln)
                sayNO;
@@ -766,43 +846,43 @@ char *prog;
                           : ibcmp_locale(s, locinput, ln)))
                sayNO;
            locinput += ln;
-           nextchar = UCHARAT(locinput);
+           nextchr = UCHARAT(locinput);
            break;
        case ANYOF:
-           s = OPERAND(scan);
-           if (nextchar < 0)
-               nextchar = UCHARAT(locinput);
-           if (!reginclass(s, nextchar))
+           s = (char *) OPERAND(scan);
+           if (nextchr < 0)
+               nextchr = UCHARAT(locinput);
+           if (!REGINCLASS(s, nextchr))
                sayNO;
-           if (!nextchar && locinput >= regeol)
+           if (!nextchr && locinput >= regeol)
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case ALNUML:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case ALNUM:
-           if (!nextchar)
+           if (!nextchr)
                sayNO;
            if (!(OP(scan) == ALNUM
-                 ? isALNUM(nextchar) : isALNUM_LC(nextchar)))
+                 ? isALNUM(nextchr) : isALNUM_LC(nextchr)))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case NALNUML:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NALNUM:
-           if (!nextchar && locinput >= regeol)
+           if (!nextchr && locinput >= regeol)
                sayNO;
            if (OP(scan) == NALNUM
-               ? isALNUM(nextchar) : isALNUM_LC(nextchar))
+               ? isALNUM(nextchr) : isALNUM_LC(nextchr))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case BOUNDL:
        case NBOUNDL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case BOUND:
        case NBOUND:
@@ -810,67 +890,65 @@ char *prog;
            ln = (locinput != regbol) ? UCHARAT(locinput - 1) : regprev;
            if (OP(scan) == BOUND || OP(scan) == NBOUND) {
                ln = isALNUM(ln);
-               n = isALNUM(nextchar);
+               n = isALNUM(nextchr);
            }
            else {
                ln = isALNUM_LC(ln);
-               n = isALNUM_LC(nextchar);
+               n = isALNUM_LC(nextchr);
            }
            if (((!ln) == (!n)) == (OP(scan) == BOUND || OP(scan) == BOUNDL))
                sayNO;
            break;
        case SPACEL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case SPACE:
-           if (!nextchar && locinput >= regeol)
+           if (!nextchr && locinput >= regeol)
                sayNO;
            if (!(OP(scan) == SPACE
-                 ? isSPACE(nextchar) : isSPACE_LC(nextchar)))
+                 ? isSPACE(nextchr) : isSPACE_LC(nextchr)))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case NSPACEL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NSPACE:
-           if (!nextchar)
+           if (!nextchr)
                sayNO;
            if (OP(scan) == SPACE
-               ? isSPACE(nextchar) : isSPACE_LC(nextchar))
+               ? isSPACE(nextchr) : isSPACE_LC(nextchr))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case DIGIT:
-           if (!isDIGIT(nextchar))
+           if (!isDIGIT(nextchr))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case NDIGIT:
-           if (!nextchar && locinput >= regeol)
+           if (!nextchr && locinput >= regeol)
                sayNO;
-           if (isDIGIT(nextchar))
+           if (isDIGIT(nextchr))
                sayNO;
-           nextchar = UCHARAT(++locinput);
+           nextchr = UCHARAT(++locinput);
            break;
        case REFFL:
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            /* FALL THROUGH */
-       case REF:
+        case REF:
        case REFF:
-           n = ARG1(scan);  /* which paren pair */
+           n = ARG(scan);  /* which paren pair */
            s = regstartp[n];
-           if (!s)
-               sayNO;
-           if (!regendp[n])
-               sayNO;
+           if (*reglastparen < n || !s)
+               sayNO;                  /* Do not match unless seen CLOSEn. */
            if (s == regendp[n])
                break;
            /* Inline the first character, for speed. */
-           if (UCHARAT(s) != nextchar &&
+           if (UCHARAT(s) != nextchr &&
                (OP(scan) == REF ||
                 (UCHARAT(s) != ((OP(scan) == REFF
-                                ? fold : fold_locale)[nextchar]))))
+                                 ? fold : fold_locale)[nextchr]))))
                sayNO;
            ln = regendp[n] - s;
            if (locinput + ln > regeol)
@@ -882,35 +960,99 @@ char *prog;
                              : ibcmp_locale(s, locinput, ln))))
                sayNO;
            locinput += ln;
-           nextchar = UCHARAT(locinput);
+           nextchr = UCHARAT(locinput);
            break;
 
        case NOTHING:
+       case TAIL:
            break;
        case BACK:
            break;
+       case EVAL:
+       {
+           dSP;
+           OP_4tree *oop = op;
+           COP *ocurcop = curcop;
+           SV **ocurpad = curpad;
+           SV *ret;
+           
+           n = ARG(scan);
+           op = (OP_4tree*)regdata->data[n];
+           DEBUG_r( PerlIO_printf(Perl_debug_log, "  re_eval 0x%x\n", op) );
+           curpad = AvARRAY((AV*)regdata->data[n + 1]);
+           if (!reg_eval_set) {
+               /* Preserve whatever is on stack now, otherwise
+                  OP_NEXTSTATE will overwrite it. */
+               SAVEINT(reg_eval_set);  /* Protect against unwinding. */
+               reg_eval_set = 1;
+               DEBUG_r(DEBUG_s(
+                   PerlIO_printf(Perl_debug_log, "  setting stack tmpbase at %i\n", stack_sp - stack_base);
+                   ));
+               SAVEINT(cxstack[cxstack_ix].blk_oldsp);
+               cxstack[cxstack_ix].blk_oldsp = stack_sp - 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);
+                  cxstack[cxstack_ix].blk_gimme = G_SCALAR; */
+           }
+
+           CALLRUNOPS();                       /* Scalar context. */
+           SPAGAIN;
+           ret = POPs;
+           PUTBACK;
+           
+           if (logical) {
+               logical = 0;
+               sw = SvTRUE(ret);
+           }
+           op = oop;
+           curpad = ocurpad;
+           curcop = ocurcop;
+           break;
+       }
        case OPEN:
-           n = ARG1(scan);  /* which paren pair */
-           regstartp[n] = locinput;
+           n = ARG(scan);  /* which paren pair */
+           reg_start_tmp[n] = locinput;
            if (n > regsize)
                regsize = n;
            break;
        case CLOSE:
-           n = ARG1(scan);  /* which paren pair */
+           n = ARG(scan);  /* which paren pair */
+           regstartp[n] = reg_start_tmp[n];
            regendp[n] = locinput;
            if (n > *reglastparen)
                *reglastparen = n;
            break;
+       case GROUPP:
+           n = ARG(scan);  /* which paren pair */
+           sw = (*reglastparen >= n && regendp[n] != NULL);
+           break;
+       case IFTHEN:
+           if (sw)
+               next = NEXTOPER(NEXTOPER(scan));
+           else {
+               next = scan + ARG(scan);
+               if (OP(next) == IFTHEN) /* Fake one. */
+                   next = NEXTOPER(NEXTOPER(next));
+           }
+           break;
+       case LOGICAL:
+           logical = 1;
+           break;
        case CURLYX: {
                CURCUR cc;
                CHECKPOINT cp = savestack_ix;
+
+               if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */
+                   next += ARG(next);
                cc.oldcc = regcc;
                regcc = &cc;
                cc.parenfloor = *reglastparen;
                cc.cur = -1;
                cc.min = ARG1(scan);
                cc.max  = ARG2(scan);
-               cc.scan = NEXTOPER(scan) + 4;
+               cc.scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
                cc.next = next;
                cc.minmod = minmod;
                cc.lastloc = 0;
@@ -931,24 +1073,34 @@ char *prog;
                 * that we can try again after backing off.
                 */
 
-               CHECKPOINT cp;
+               CHECKPOINT cp, lastcp;
                CURCUR* cc = regcc;
+               char *lastloc = cc->lastloc; /* Detection of 0-len. */
+               
                n = cc->cur + 1;        /* how many we know we matched */
                reginput = locinput;
 
-#ifdef DEBUGGING
-               if (regnarrate)
-                   PerlIO_printf(Perl_debug_log, "%*s  %ld  %lx\n", regindent*2, "",
-                       (long)n, (long)cc);
-#endif
+               DEBUG_r(
+                   PerlIO_printf(Perl_debug_log, 
+                                 "%*s  %ld out of %ld..%ld  cc=%lx\n", 
+                                 REPORT_CODE_OFF+regindent*2, "",
+                                 (long)n, (long)cc->min, 
+                                 (long)cc->max, (long)cc)
+                   );
 
                /* If degenerate scan matches "", assume scan done. */
 
                if (locinput == cc->lastloc && n >= cc->min) {
                    regcc = cc->oldcc;
                    ln = regcc->cur;
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  empty match detected, try continuation...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
                    if (regmatch(cc->next))
                        sayYES;
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  failed...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
                    regcc->cur = ln;
                    regcc = cc;
                    sayNO;
@@ -962,6 +1114,10 @@ char *prog;
                    if (regmatch(cc->scan))
                        sayYES;
                    cc->cur = n - 1;
+                   cc->lastloc = lastloc;
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  failed...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
                    sayNO;
                }
 
@@ -971,28 +1127,45 @@ char *prog;
                    regcc = cc->oldcc;
                    ln = regcc->cur;
                    cp = regcppush(cc->parenfloor);
+                   REGCP_SET;
                    if (regmatch(cc->next)) {
-                       regcppartblow(cp);
+                       regcpblow(cp);
                        sayYES; /* All done. */
                    }
+                   REGCP_UNWIND;
                    regcppop();
                    regcc->cur = ln;
                    regcc = cc;
 
-                   if (n >= cc->max)   /* Maximum greed exceeded? */
+                   if (n >= cc->max) { /* Maximum greed exceeded? */
+                       if (dowarn && n >= REG_INFTY 
+                           && !(reg_flags & RF_warned)) {
+                           reg_flags |= RF_warned;
+                           warn("count exceeded %d", REG_INFTY - 1);
+                       }
                        sayNO;
+                   }
 
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  trying longer...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
                    /* Try scanning more and see if it helps. */
                    reginput = locinput;
                    cc->cur = n;
                    cc->lastloc = locinput;
                    cp = regcppush(cc->parenfloor);
+                   REGCP_SET;
                    if (regmatch(cc->scan)) {
-                       regcppartblow(cp);
+                       regcpblow(cp);
                        sayYES;
                    }
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  failed...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
+                   REGCP_UNWIND;
                    regcppop();
                    cc->cur = n - 1;
+                   cc->lastloc = lastloc;
                    sayNO;
                }
 
@@ -1002,12 +1175,21 @@ char *prog;
                    cp = regcppush(cc->parenfloor);
                    cc->cur = n;
                    cc->lastloc = locinput;
+                   REGCP_SET;
                    if (regmatch(cc->scan)) {
-                       regcppartblow(cp);
+                       regcpblow(cp);
                        sayYES;
                    }
+                   REGCP_UNWIND;
                    regcppop();         /* Restore some previous $<digit>s? */
                    reginput = locinput;
+                   DEBUG_r(
+                       PerlIO_printf(Perl_debug_log, "%*s  failed, try continuation...\n", REPORT_CODE_OFF+regindent*2, "")
+                       );
+               }
+               if (dowarn && n >= REG_INFTY && !(reg_flags & RF_warned)) {
+                   reg_flags |= RF_warned;
+                   warn("count exceeded %d", REG_INFTY - 1);
                }
 
                /* Failed deeper matches of scan, so see if this one works. */
@@ -1015,35 +1197,57 @@ char *prog;
                ln = regcc->cur;
                if (regmatch(cc->next))
                    sayYES;
+               DEBUG_r(
+                   PerlIO_printf(Perl_debug_log, "%*s  failed...\n", REPORT_CODE_OFF+regindent*2, "")
+                   );
                regcc->cur = ln;
                regcc = cc;
                cc->cur = n - 1;
+               cc->lastloc = lastloc;
                sayNO;
            }
            /* NOT REACHED */
-       case BRANCH: {
-               if (OP(next) != BRANCH)   /* No choice. */
-                   next = NEXTOPER(scan);/* Avoid recursion. */
+       case BRANCHJ: 
+           next = scan + ARG(scan);
+           if (next == scan)
+               next = NULL;
+           inner = NEXTOPER(NEXTOPER(scan));
+           goto do_branch;
+       case BRANCH: 
+           inner = NEXTOPER(scan);
+         do_branch:
+           {
+               CHECKPOINT lastcp;
+               c1 = OP(scan);
+               if (OP(next) != c1)     /* No choice. */
+                   next = inner;       /* Avoid recursion. */
                else {
                    int lastparen = *reglastparen;
+
+                   REGCP_SET;
                    do {
                        reginput = locinput;
-                       if (regmatch(NEXTOPER(scan)))
+                       if (regmatch(inner))
                            sayYES;
+                       REGCP_UNWIND;
                        for (n = *reglastparen; n > lastparen; n--)
                            regendp[n] = 0;
                        *reglastparen = n;
-                           
+                       scan = next;
 #ifdef REGALIGN
                        /*SUPPRESS 560*/
-                       if (n = NEXT(scan))
-                           scan += n;
+                       if (n = (c1 == BRANCH ? NEXT_OFF(next) : ARG(next)))
+                           next += n;
                        else
-                           scan = NULL;
+                           next = NULL;
 #else
-                       scan = regnext(scan);
+                       next = regnext(next);
 #endif
-                   } while (scan != NULL && OP(scan) == BRANCH);
+                       inner = NEXTOPER(scan);
+                       if (c1 == BRANCHJ) {
+                           inner = NEXTOPER(inner);
+                       }
+                   } while (scan != NULL && OP(scan) == c1);
                    sayNO;
                    /* NOTREACHED */
                }
@@ -1052,25 +1256,164 @@ char *prog;
        case MINMOD:
            minmod = 1;
            break;
+       case CURLYM:
+       {
+           I32 l;
+           CHECKPOINT lastcp;
+           
+           /* We suppose that the next guy does not need
+              backtracking: in particular, it is of constant length,
+              and has no parenths to influence future backrefs. */
+           ln = ARG1(scan);  /* min to match */
+           n  = ARG2(scan);  /* max to match */
+#ifdef REGALIGN_STRUCT
+           paren = scan->flags;
+           if (paren) {
+               if (paren > regsize)
+                   regsize = paren;
+               if (paren > *reglastparen)
+                   *reglastparen = paren;
+           }
+#endif 
+           scan = NEXTOPER(scan) + NODE_STEP_REGNODE;
+           if (paren)
+               scan += NEXT_OFF(scan); /* Skip former OPEN. */
+           reginput = locinput;
+           if (minmod) {
+               minmod = 0;
+               if (ln && regrepeat_hard(scan, ln, &l) < ln)
+                   sayNO;
+               if (ln && l == 0 && n >= ln
+                   /* In fact, this is tricky.  If paren, then the
+                      fact that we did/didnot match may influence
+                      future execution. */
+                   && !(paren && ln == 0))
+                   ln = n;
+               locinput = reginput;
+               if (regkind[(U8)OP(next)] == EXACT) {
+                   c1 = UCHARAT(OPERAND(next) + 1);
+                   if (OP(next) == EXACTF)
+                       c2 = fold[c1];
+                   else if (OP(next) == EXACTFL)
+                       c2 = fold_locale[c1];
+                   else
+                       c2 = c1;
+               } else
+                   c1 = c2 = -1000;
+               REGCP_SET;
+               /* This may be improved if l == 0.  */
+               while (n >= ln || (n == REG_INFTY && ln > 0 && l)) { /* ln overflow ? */
+                   /* If it could work, try it. */
+                   if (c1 == -1000 ||
+                       UCHARAT(reginput) == c1 ||
+                       UCHARAT(reginput) == c2)
+                   {
+                       if (paren) {
+                           if (n) {
+                               regstartp[paren] = reginput - l;
+                               regendp[paren] = reginput;
+                           } else
+                               regendp[paren] = NULL;
+                       }
+                       if (regmatch(next))
+                           sayYES;
+                       REGCP_UNWIND;
+                   }
+                   /* Couldn't or didn't -- move forward. */
+                   reginput = locinput;
+                   if (regrepeat_hard(scan, 1, &l)) {
+                       ln++;
+                       locinput = reginput;
+                   }
+                   else
+                       sayNO;
+               }
+           } else {
+               n = regrepeat_hard(scan, n, &l);
+               if (n != 0 && l == 0
+                   /* In fact, this is tricky.  If paren, then the
+                      fact that we did/didnot match may influence
+                      future execution. */
+                   && !(paren && ln == 0))
+                   ln = n;
+               locinput = reginput;
+               DEBUG_r(
+                   PerlIO_printf(Perl_debug_log, "%*s  matched %ld times, len=%ld...\n", REPORT_CODE_OFF+regindent*2, "", n, l)
+                   );
+               if (n >= ln) {
+                   if (regkind[(U8)OP(next)] == EXACT) {
+                       c1 = UCHARAT(OPERAND(next) + 1);
+                       if (OP(next) == EXACTF)
+                           c2 = fold[c1];
+                       else if (OP(next) == EXACTFL)
+                           c2 = fold_locale[c1];
+                       else
+                           c2 = c1;
+                   } else
+                       c1 = c2 = -1000;
+               }
+               REGCP_SET;
+               while (n >= ln) {
+                   /* If it could work, try it. */
+                   if (c1 == -1000 ||
+                       UCHARAT(reginput) == c1 ||
+                       UCHARAT(reginput) == c2)
+                       {
+                           DEBUG_r(
+                               PerlIO_printf(Perl_debug_log, "%*s  trying tail with n=%ld...\n", REPORT_CODE_OFF+regindent*2, "", n)
+                               );
+                           if (paren) {
+                               if (n) {
+                                   regstartp[paren] = reginput - l;
+                                   regendp[paren] = reginput;
+                               } else
+                                   regendp[paren] = NULL;
+                           }
+                           if (regmatch(next))
+                               sayYES;
+                           REGCP_UNWIND;
+                       }
+                   /* Couldn't or didn't -- back up. */
+                   n--;
+                   locinput -= l;
+                   reginput = locinput;
+               }
+           }
+           sayNO;
+           break;
+       }
+       case CURLYN:
+           paren = scan->flags;        /* Which paren to set */
+           if (paren > regsize)
+               regsize = paren;
+           if (paren > *reglastparen)
+               *reglastparen = paren;
+           ln = ARG1(scan);  /* min to match */
+           n  = ARG2(scan);  /* max to match */
+            scan = regnext(NEXTOPER(scan) + NODE_STEP_REGNODE);
+           goto repeat;
        case CURLY:
+           paren = 0;
            ln = ARG1(scan);  /* min to match */
            n  = ARG2(scan);  /* max to match */
-           scan = NEXTOPER(scan) + 4;
+           scan = NEXTOPER(scan) + NODE_STEP_REGNODE;
            goto repeat;
        case STAR:
            ln = 0;
-           n = 32767;
+           n = REG_INFTY;
            scan = NEXTOPER(scan);
+           paren = 0;
            goto repeat;
        case PLUS:
+           ln = 1;
+           n = REG_INFTY;
+           scan = NEXTOPER(scan);
+           paren = 0;
+         repeat:
            /*
            * Lookahead to avoid useless match attempts
            * when we know what character comes next.
            */
-           ln = 1;
-           n = 32767;
-           scan = NEXTOPER(scan);
-         repeat:
            if (regkind[(U8)OP(next)] == EXACT) {
                c1 = UCHARAT(OPERAND(next) + 1);
                if (OP(next) == EXACTF)
@@ -1084,67 +1427,132 @@ char *prog;
                c1 = c2 = -1000;
            reginput = locinput;
            if (minmod) {
+               CHECKPOINT lastcp;
                minmod = 0;
                if (ln && regrepeat(scan, ln) < ln)
                    sayNO;
-               while (n >= ln || (n == 32767 && ln > 0)) { /* ln overflow ? */
+               REGCP_SET;
+               while (n >= ln || (n == REG_INFTY && ln > 0)) { /* ln overflow ? */
                    /* If it could work, try it. */
                    if (c1 == -1000 ||
                        UCHARAT(reginput) == c1 ||
                        UCHARAT(reginput) == c2)
                    {
+                       if (paren) {
+                           if (n) {
+                               regstartp[paren] = reginput - 1;
+                               regendp[paren] = reginput;
+                           } else
+                               regendp[paren] = NULL;
+                       }
                        if (regmatch(next))
                            sayYES;
+                       REGCP_UNWIND;
                    }
-                   /* Couldn't or didn't -- back up. */
+                   /* Couldn't or didn't -- move forward. */
                    reginput = locinput + ln;
                    if (regrepeat(scan, 1)) {
                        ln++;
                        reginput = locinput + ln;
-                   }
-                   else
+                   } else
                        sayNO;
                }
            }
            else {
+               CHECKPOINT lastcp;
                n = regrepeat(scan, n);
                if (ln < n && regkind[(U8)OP(next)] == EOL &&
-                   (!multiline || OP(next) == SEOL))
+                   (!multiline  || OP(next) == SEOL))
                    ln = n;                     /* why back off? */
-               while (n >= ln) {
-                   /* If it could work, try it. */
-                   if (c1 == -1000 ||
-                       UCHARAT(reginput) == c1 ||
-                       UCHARAT(reginput) == c2)
-                   {
-                       if (regmatch(next))
-                           sayYES;
+               REGCP_SET;
+               if (paren) {
+                   while (n >= ln) {
+                       /* If it could work, try it. */
+                       if (c1 == -1000 ||
+                           UCHARAT(reginput) == c1 ||
+                           UCHARAT(reginput) == c2)
+                           {
+                               if (paren && n) {
+                                   if (n) {
+                                       regstartp[paren] = reginput - 1;
+                                       regendp[paren] = reginput;
+                                   } else
+                                       regendp[paren] = NULL;
+                               }
+                               if (regmatch(next))
+                                   sayYES;
+                               REGCP_UNWIND;
+                           }
+                       /* Couldn't or didn't -- back up. */
+                       n--;
+                       reginput = locinput + n;
+                   }
+               } else {
+                   while (n >= ln) {
+                       /* If it could work, try it. */
+                       if (c1 == -1000 ||
+                           UCHARAT(reginput) == c1 ||
+                           UCHARAT(reginput) == c2)
+                           {
+                               if (regmatch(next))
+                                   sayYES;
+                               REGCP_UNWIND;
+                           }
+                       /* Couldn't or didn't -- back up. */
+                       n--;
+                       reginput = locinput + n;
                    }
-                   /* Couldn't or didn't -- back up. */
-                   n--;
-                   reginput = locinput + n;
                }
            }
            sayNO;
+           break;
        case SUCCEED:
        case END:
            reginput = locinput;        /* put where regtry can find it */
            sayYES;                     /* Success! */
-       case IFMATCH:
-           reginput = locinput;
-           scan = NEXTOPER(scan);
-           if (!regmatch(scan))
-               sayNO;
-           break;
+       case SUSPEND:
+           n = 1;
+           goto do_ifmatch;        
        case UNLESSM:
-           reginput = locinput;
-           scan = NEXTOPER(scan);
-           if (regmatch(scan))
-               sayNO;
+           n = 0;
+           if (locinput < bostr + scan->flags) 
+               goto say_yes;
+           goto do_ifmatch;
+       case IFMATCH:
+           n = 1;
+           if (locinput < bostr + scan->flags) 
+               goto say_no;
+         do_ifmatch:
+           reginput = locinput - scan->flags;
+           inner = NEXTOPER(NEXTOPER(scan));
+           if (regmatch(inner) != n) {
+             say_no:
+               if (logical) {
+                   logical = 0;
+                   sw = 0;
+                   goto do_longjump;
+               } else
+                   sayNO;
+           }
+         say_yes:
+           if (logical) {
+               logical = 0;
+               sw = 1;
+           }
+           if (OP(scan) == SUSPEND) {
+               locinput = reginput;
+               nextchr = UCHARAT(locinput);
+           }
+           /* FALL THROUGH. */
+       case LONGJMP:
+         do_longjump:
+           next = scan + ARG(scan);
+           if (next == scan)
+               next = NULL;
            break;
        default:
            PerlIO_printf(PerlIO_stderr(), "%lx %d\n",
-                         (unsigned long)scan, scan[1]);
+                         (unsigned long)scan, OP(scan));
            FAIL("regexp memory corruption");
        }
        scan = next;
@@ -1179,10 +1587,8 @@ no:
  * That was true before, but now we assume scan - reginput is the count,
  * rather than incrementing count on every character.]
  */
-static I32
-regrepeat(p, max)
-char *p;
-I32 max;
+STATIC I32
+regrepeat(regnode *p, I32 max)
 {
     register char *scan;
     register char *opnd;
@@ -1190,9 +1596,9 @@ I32 max;
     register char *loceol = regeol;
 
     scan = reginput;
-    if (max != 32767 && max < loceol - scan)
+    if (max != REG_INFTY && max < loceol - scan)
       loceol = scan + max;
-    opnd = OPERAND(p);
+    opnd = (char *) OPERAND(p);
     switch (OP(p)) {
     case ANY:
        while (scan < loceol && *scan != '\n')
@@ -1213,14 +1619,14 @@ I32 max;
            scan++;
        break;
     case EXACTFL:      /* length of string is 1 */
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
        c = UCHARAT(++opnd);
        while (scan < loceol &&
               (UCHARAT(scan) == c || UCHARAT(scan) == fold_locale[c]))
            scan++;
        break;
     case ANYOF:
-       while (scan < loceol && reginclass(opnd, *scan))
+       while (scan < loceol && REGINCLASS(opnd, *scan))
            scan++;
        break;
     case ALNUM:
@@ -1228,7 +1634,7 @@ I32 max;
            scan++;
        break;
     case ALNUML:
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
        while (scan < loceol && isALNUM_LC(*scan))
            scan++;
        break;
@@ -1237,7 +1643,7 @@ I32 max;
            scan++;
        break;
     case NALNUML:
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
        while (scan < loceol && !isALNUM_LC(*scan))
            scan++;
        break;
@@ -1246,7 +1652,7 @@ I32 max;
            scan++;
        break;
     case SPACEL:
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
        while (scan < loceol && isSPACE_LC(*scan))
            scan++;
        break;
@@ -1255,7 +1661,7 @@ I32 max;
            scan++;
        break;
     case NSPACEL:
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
        while (scan < loceol && !isSPACE_LC(*scan))
            scan++;
        break;
@@ -1274,38 +1680,79 @@ I32 max;
     c = scan - reginput;
     reginput = scan;
 
+    DEBUG_r( 
+       {
+               SV *prop = sv_newmortal();
+
+               regprop(prop, p);
+               PerlIO_printf(Perl_debug_log, 
+                             "%*s  %s can match %ld times out of %ld...\n", 
+                             REPORT_CODE_OFF+1, "", SvPVX(prop),c,max);
+       });
+    
     return(c);
 }
 
 /*
+ - regrepeat_hard - repeatedly match something, report total lenth and length
+ * 
+ * The repeater is supposed to have constant length.
+ */
+
+STATIC I32
+regrepeat_hard(regnode *p, I32 max, I32 *lp)
+{
+    register char *scan;
+    register char *start;
+    register char *loceol = regeol;
+    I32 l = -1;
+
+    start = reginput;
+    while (reginput < loceol && (scan = reginput, regmatch(p))) {
+       if (l == -1) {
+           *lp = l = reginput - start;
+           if (max != REG_INFTY && l*max < loceol - scan)
+               loceol = scan + l*max;
+           if (l == 0) {
+               return max;
+           }
+       }
+    }
+    if (reginput < loceol)
+       reginput = scan;
+    else
+       scan = reginput;
+    
+    return (scan - start)/l;
+}
+
+/*
  - regclass - determine if a character falls into a character class
  */
 
-static bool
-reginclass(p, c)
-register char *p;
-register I32 c;
+STATIC bool
+reginclass(register char *p, register I32 c)
 {
     char flags = *p;
     bool match = FALSE;
 
     c &= 0xFF;
-    if (p[1 + (c >> 3)] & (1 << (c & 7)))
+    if (ANYOF_TEST(p, c))
        match = TRUE;
     else if (flags & ANYOF_FOLD) {
        I32 cf;
        if (flags & ANYOF_LOCALE) {
-           regtainted = TRUE;
+           reg_flags |= RF_tainted;
            cf = fold_locale[c];
        }
        else
            cf = fold[c];
-       if (p[1 + (cf >> 3)] & (1 << (cf & 7)))
+       if (ANYOF_TEST(p, cf))
            match = TRUE;
     }
 
     if (!match && (flags & ANYOF_ISA)) {
-       regtainted = TRUE;
+       reg_flags |= RF_tainted;
 
        if (((flags & ANYOF_ALNUML)  && isALNUM_LC(c))  ||
            ((flags & ANYOF_NALNUML) && !isALNUM_LC(c)) ||
@@ -1316,34 +1763,8 @@ register I32 c;
        }
     }
 
-    return match ^ ((flags & ANYOF_INVERT) != 0);
+    return (flags & ANYOF_INVERT) ? !match : match;
 }
 
-/*
- - regnext - dig the "next" pointer out of a node
- *
- * [Note, when REGALIGN is defined there are two places in regmatch()
- * that bypass this code for speed.]
- */
-char *
-regnext(p)
-register char *p;
-{
-    register I32 offset;
-
-    if (p == &regdummy)
-       return(NULL);
 
-    offset = NEXT(p);
-    if (offset == 0)
-       return(NULL);
 
-#ifdef REGALIGN
-    return(p+offset);
-#else
-    if (OP(p) == BACK)
-       return(p-offset);
-    else
-       return(p+offset);
-#endif
-}