regexec(): skip second intuit() call

A few commits ago, the call to intuit() done by the *callers* of
regexec() was moved into regexec() itself. Since regexec() could also call
intuit(), this temporarily led to the situation where intuit() was
harmlessly but inefficiently called twice. The last few commits have
removed the subtle differences between the conditions for each of the two
call points, so the second call to intuit() can now be removed.

A consequence of this is that we have to adjust the usage of the
'startpos' verses 's' variables; the original intent was that
startpos was constant, while s moved forward in the string after intuit
etc. This got a bit lost during the recent reorganisation, but is now
re-established. (startpos isn't quite constant: it will contain any
initial adjustment for \G.)

diff --git a/regexec.c b/regexec.c
index 43d66c9..6b6e7c9 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -2264,12 +2264,14 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
         return 0;
     }
 
+    s = startpos;
+
     if ((RX_EXTFLAGS(rx) & RXf_USE_INTUIT)
         && !(flags & REXEC_CHECKED))
     {
-       startpos = re_intuit_start(rx, sv, strbeg, startpos, strend,
+       s = re_intuit_start(rx, sv, strbeg, startpos, strend,
                                     flags, NULL);
-       if (!startpos)
+       if (!s)
            return 0;
 
        if (RX_EXTFLAGS(rx) & RXf_CHECK_ALL) {
@@ -2286,10 +2288,10 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
                                         strbeg, strend,
                                         sv, flags, utf8_target);
 
-            prog->offs[0].start = startpos - strbeg;
+            prog->offs[0].start = s - strbeg;
             prog->offs[0].end = utf8_target
-                ? (char*)utf8_hop((U8*)startpos, prog->minlenret) - strbeg
-                : startpos - strbeg + prog->minlenret;
+                ? (char*)utf8_hop((U8*)s, prog->minlenret) - strbeg
+                : s - strbeg + prog->minlenret;
            return 1;
         }
     }
@@ -2304,7 +2306,7 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
 
     multiline = prog->extflags & RXf_PMf_MULTILINE;
     
-    if (strend - startpos < (minlen+(prog->check_offset_min<0?prog->check_offset_min:0))) {
+    if (strend - s < (minlen+(prog->check_offset_min<0?prog->check_offset_min:0))) {
         DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                              "String too short [regexec_flags]...\n"));
        goto phooey;
@@ -2392,7 +2394,6 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
     }
 
     /* If there is a "must appear" string, look for it. */
-    s = startpos;
 
     if (prog->extflags & RXf_GPOS_SEEN) { /* Need to set reginfo->ganch */
        MAGIC *mg;
@@ -2440,15 +2441,6 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
            PTR2UV(prog->offs)
        ));
     }
-    if (!(flags & REXEC_CHECKED) && (prog->check_substr != NULL || prog->check_utf8 != NULL)) {
-       s = re_intuit_start(rx, sv, strbeg, s, strend, flags, NULL);
-       if (!s) {
-           DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "Not present...\n"));
-           goto phooey;        /* not present */
-       }
-    }
-
-
 
     /* Simplest case:  anchored match need be tried only once. */
     /*  [unless only anchor is BOL and multiline is set] */