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regmatch(): make IFMATCH use PUSH_STACK rather than fake recursion
[perl5.git] / regexec.c
index 53ec117..890736c 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -2234,7 +2234,6 @@ typedef union re_unwind_t {
 #define sayNO goto no
 #define sayNO_ANYOF goto no_anyof
 #define sayYES_FINAL goto yes_final
-#define sayYES_LOUD  goto yes_loud
 #define sayNO_FINAL  goto no_final
 #define sayNO_SILENT goto do_no
 #define saySAME(x) if (x) goto yes; else goto no
@@ -3875,7 +3874,11 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
            st->u.curlym.maxwanted = st->minmod ? st->ln : n;
            if (st->u.curlym.maxwanted) {
                while (PL_reginput < PL_regeol && st->u.curlym.matches < st->u.curlym.maxwanted) {
+                   /* resume to current state on success */
+                   st->u.yes.prev_yes_state = yes_state;
+                   yes_state = st;
                    REGMATCH(scan, CURLYM1);
+                   yes_state = st->u.yes.prev_yes_state;
                    /*** all unsaved local vars undefined at this point */
                    if (!result)
                        break;
@@ -3945,15 +3948,24 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
                            else
                                PL_regendp[st->u.curlym.paren] = -1;
                        }
+                       /* resume to current state on success */
+                       st->u.yes.prev_yes_state = yes_state;
+                       yes_state = st;
                        REGMATCH(next, CURLYM2);
+                       yes_state = st->u.yes.prev_yes_state;
                        /*** all unsaved local vars undefined at this point */
                        if (result)
-                           sayYES;
+                           /* XXX tmp sayYES; */
+                           sayYES_FINAL;
                        REGCP_UNWIND(st->u.curlym.lastcp);
                    }
                    /* Couldn't or didn't -- move forward. */
                    PL_reginput = locinput;
+                   /* resume to current state on success */
+                   st->u.yes.prev_yes_state = yes_state;
+                   yes_state = st;
                    REGMATCH(scan, CURLYM3);
+                   yes_state = st->u.yes.prev_yes_state;
                    /*** all unsaved local vars undefined at this point */
                    if (result) {
                        st->ln++;
@@ -4018,10 +4030,15 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
                            else
                                PL_regendp[st->u.curlym.paren] = -1;
                        }
+                       /* resume to current state on success */
+                       st->u.yes.prev_yes_state = yes_state;
+                       yes_state = st;
                        REGMATCH(next, CURLYM4);
+                       yes_state = st->u.yes.prev_yes_state;
                        /*** all unsaved local vars undefined at this point */
                        if (result)
-                           sayYES;
+                           /* XXX tmp sayYES; */
+                           sayYES_FINAL;
                        REGCP_UNWIND(st->u.curlym.lastcp);
                    }
                    /* Couldn't or didn't -- back up. */
@@ -4298,60 +4315,57 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
            }
            PL_reginput = locinput;     /* put where regtry can find it */
            sayYES_FINAL;               /* Success! */
-       case SUCCEED:
+
+       case SUCCEED: /* successful SUSPEND/UNLESSM/IFMATCH/CURLYM */
+           DEBUG_EXECUTE_r(
+           PerlIO_printf(Perl_debug_log,
+               "%*s  %ssubpattern success...%s\n",
+               REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4], PL_colors[5]));
            PL_reginput = locinput;     /* put where regtry can find it */
-           sayYES_LOUD;                /* Success! */
-       case SUSPEND:
-           n = 1;
+           sayYES_FINAL;               /* Success! */
+
+       case SUSPEND:   /* (?>FOO) */
+           st->u.ifmatch.wanted = 1;
            PL_reginput = locinput;
            goto do_ifmatch;    
-       case UNLESSM:
-           n = 0;
-           if (scan->flags) {
-               char * const s = HOPBACKc(locinput, scan->flags);
-               if (!s)
-                   goto say_yes;
-               PL_reginput = s;
-           }
-           else
-               PL_reginput = locinput;
-           goto do_ifmatch;
-       case IFMATCH:
-           n = 1;
+
+       case UNLESSM:   /* -ve lookaround: (?!FOO), or with flags, (?<!foo) */
+           st->u.ifmatch.wanted = 0;
+           goto ifmatch_trivial_fail_test;
+
+       case IFMATCH:   /* +ve lookaround: (?=FOO), or with flags, (?<=foo) */
+           st->u.ifmatch.wanted = 1;
+         ifmatch_trivial_fail_test:
            if (scan->flags) {
                char * const s = HOPBACKc(locinput, scan->flags);
-               if (!s)
-                   goto say_no;
+               if (!s) {
+                   /* trivial fail */
+                   if (st->logical) {
+                       st->logical = 0;
+                       st->sw = 1 - st->u.ifmatch.wanted;
+                   }
+                   else if (st->u.ifmatch.wanted)
+                       sayNO;
+                   next = scan + ARG(scan);
+                   if (next == scan)
+                       next = NULL;
+                   break;
+               }
                PL_reginput = s;
            }
            else
                PL_reginput = locinput;
 
          do_ifmatch:
-           REGMATCH(NEXTOPER(NEXTOPER(scan)), IFMATCH);
-           /*** all unsaved local vars undefined at this point */
-           if (result != n) {
-             say_no:
-               if (st->logical) {
-                   st->logical = 0;
-                   st->sw = 0;
-                   goto do_longjump;
-               }
-               else
-                   sayNO;
-           }
-         say_yes:
-           if (st->logical) {
-               st->logical = 0;
-               st->sw = 1;
-           }
-           if (OP(scan) == SUSPEND) {
-               locinput = PL_reginput;
-               nextchr = UCHARAT(locinput);
-           }
-           /* FALL THROUGH. */
+           /* resume to current state on success */
+           st->u.yes.prev_yes_state = yes_state;
+           yes_state = st;
+           PUSH_STATE(newst, resume_IFMATCH);
+           st = newst;
+           next = NEXTOPER(NEXTOPER(scan));
+           break;
+
        case LONGJMP:
-         do_longjump:
            next = scan + ARG(scan);
            if (next == scan)
                next = NULL;
@@ -4412,19 +4426,17 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
     /*NOTREACHED*/
     sayNO;
 
-yes_loud:
-    DEBUG_EXECUTE_r(
-       PerlIO_printf(Perl_debug_log,
-                     "%*s  %scould match...%s\n",
-                     REPORT_CODE_OFF+PL_regindent*2, "", PL_colors[4], PL_colors[5])
-       );
-    goto yes;
 yes_final:
 
     if (yes_state) {
        /* we have successfully completed a subexpression, but we must now
         * pop to the state marked by yes_state and continue from there */
 
+       /*XXX tmp for CURLYM*/
+       regmatch_slab *oslab = PL_regmatch_slab;
+       regmatch_state *ost = st, *oys=yes_state;
+       int odepth = depth;
+
        assert(st != yes_state);
        while (yes_state < SLAB_FIRST(PL_regmatch_slab)
            || yes_state > SLAB_LAST(PL_regmatch_slab))
@@ -4435,7 +4447,7 @@ yes_final:
            st = SLAB_LAST(PL_regmatch_slab);
        }
        depth -= (st - yes_state);
-       DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "POP STATE TO (%d)\n", depth)); \
+       DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "POP STATE TO (%d)\n", depth));
        st = yes_state;
        yes_state = st->u.yes.prev_yes_state;
        PL_regmatch_state = st;
@@ -4461,6 +4473,38 @@ yes_final:
            next        = st->next;
            goto reenter;
 
+       case resume_IFMATCH:
+           if (st->logical) {
+               st->logical = 0;
+               st->sw = st->u.ifmatch.wanted;
+           }
+           else if (!st->u.ifmatch.wanted)
+               sayNO;
+
+           if (OP(st->scan) == SUSPEND)
+               locinput = PL_reginput;
+           else {
+               locinput = PL_reginput = st->locinput;
+               nextchr = UCHARAT(locinput);
+           }
+           next = st->scan + ARG(st->scan);
+           if (next == st->scan)
+               next = NULL;
+           goto reenter;
+
+       /* XXX tmp  don't handle yes_state yet */
+       case resume_CURLYM1:
+       case resume_CURLYM2:
+       case resume_CURLYM3:
+       case resume_CURLYM4:
+           PL_regmatch_slab =oslab;
+           st = ost;
+           PL_regmatch_state = st;
+           depth = odepth;
+           yes_state = oys;
+           DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "XXX revering a CURLYM\n"));
+           goto yes;
+
        default:
            Perl_croak(aTHX_ "unexpected yes reume state");
        }
@@ -4508,8 +4552,6 @@ yes:
            goto resume_point_CURLYM3;
        case resume_CURLYM4:
            goto resume_point_CURLYM4;
-       case resume_IFMATCH:
-           goto resume_point_IFMATCH;
        case resume_PLUS1:
            goto resume_point_PLUS1;
        case resume_PLUS2:
@@ -4519,6 +4561,7 @@ yes:
        case resume_PLUS4:
            goto resume_point_PLUS4;
 
+       case resume_IFMATCH:
        case resume_EVAL:
        default:
            Perl_croak(aTHX_ "regexp resume memory corruption");
@@ -4638,7 +4681,22 @@ do_no:
        case resume_CURLYM4:
            goto resume_point_CURLYM4;
        case resume_IFMATCH:
-           goto resume_point_IFMATCH;
+           yes_state = st->u.yes.prev_yes_state;
+           if (st->logical) {
+               st->logical = 0;
+               st->sw = !st->u.ifmatch.wanted;
+           }
+           else if (st->u.ifmatch.wanted)
+               sayNO;
+
+           assert(OP(scan) != SUSPEND); /* XXX DAPM tmp */
+           locinput = PL_reginput = st->locinput;
+           nextchr = UCHARAT(locinput);
+           next = scan + ARG(scan);
+           if (next == scan)
+               next = NULL;
+           goto reenter;
+
        case resume_PLUS1:
            goto resume_point_PLUS1;
        case resume_PLUS2: