Speed up .*? and half-fix UTF lookbehind

	Message-Id: <199812040505.AAA16616@monk.mps.ohio-state.edu>

p4raw-id: //depot/perl@2749

diff --git a/regexec.c b/regexec.c
index c410627..9c1243e 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -2196,6 +2196,50 @@ regmatch(regnode *prog)
                    sayNO;
                locinput = PL_reginput;
                REGCP_SET;
+               if (c1 != -1000) {
+                   char *e = locinput + n - ln; /* Should not check after this */
+                   char *old = locinput;
+
+                   if (e >= PL_regeol || (n == REG_INFTY))
+                       e = PL_regeol - 1;
+                   while (1) {
+                       /* Find place 'next' could work */
+                       if (c1 == c2) {
+                           while (locinput <= e && *locinput != c1)
+                               locinput++;
+                       } else {
+                           while (locinput <= e 
+                                  && *locinput != c1
+                                  && *locinput != c2)
+                               locinput++;                         
+                       }
+                       if (locinput > e) 
+                           sayNO;
+                       /* PL_reginput == old now */
+                       if (locinput != old) {
+                           ln = 1;     /* Did some */
+                           if (regrepeat(scan, locinput - old) <
+                                locinput - old)
+                               sayNO;
+                       }
+                       /* PL_reginput == locinput now */
+                       if (paren) {
+                           if (ln) {
+                               PL_regstartp[paren] = HOPc(locinput, -1);
+                               PL_regendp[paren] = locinput;
+                           }
+                           else
+                               PL_regendp[paren] = NULL;
+                       }
+                       if (regmatch(next))
+                           sayYES;
+                       PL_reginput = locinput; /* Could be reset... */
+                       REGCP_UNWIND;
+                       /* Couldn't or didn't -- move forward. */
+                       old = locinput++;
+                   }
+               }
+               else
                while (n >= ln || (n == REG_INFTY && ln > 0)) { /* ln overflow ? */
                    /* If it could work, try it. */
                    if (c1 == -1000 ||
@@ -2323,10 +2367,20 @@ regmatch(regnode *prog)
        case UNLESSM:
            n = 0;
            if (scan->flags) {
-               s = HOPMAYBEc(locinput, -scan->flags);
-               if (!s)
-                   goto say_yes;
-               PL_reginput = s;
+               if (UTF) {              /* XXXX This is absolutely
+                                          broken, we read before
+                                          start of string. */
+                   s = HOPMAYBEc(locinput, -scan->flags);
+                   if (!s)
+                       goto say_yes;
+                   PL_reginput = s;
+               }
+               else {
+                   if (locinput < PL_bostr + scan->flags) 
+                       goto say_yes;
+                   PL_reginput = locinput - scan->flags;
+                   goto do_ifmatch;
+               }
            }
            else
                PL_reginput = locinput;
@@ -2334,10 +2388,20 @@ regmatch(regnode *prog)
        case IFMATCH:
            n = 1;
            if (scan->flags) {
-               s = HOPMAYBEc(locinput, -scan->flags);
-               if (!s || s < PL_bostr)
-                   goto say_no;
-               PL_reginput = s;
+               if (UTF) {              /* XXXX This is absolutely
+                                          broken, we read before
+                                          start of string. */
+                   s = HOPMAYBEc(locinput, -scan->flags);
+                   if (!s || s < PL_bostr)
+                       goto say_no;
+                   PL_reginput = s;
+               }
+               else {
+                   if (locinput < PL_bostr + scan->flags) 
+                       goto say_no;
+                   PL_reginput = locinput - scan->flags;
+                   goto do_ifmatch;
+               }
            }
            else
                PL_reginput = locinput;