move intuit call from pp_match() into regexec()

Currently the main part of pp_match() looks like:

    if (can_use_intuit) {
        if (!intuit_start())
            goto nope;
        if (can_match_based_only_on_intuit_result) {
            ... set up $&, $-[0] etc ...
            goto gotcha;
        }
    }
    if (!regexec(..., REXEC_CHECKED|r_flags))
        goto nope;

  gotcha:
    ...

This rather breaks the regex API encapulation. The caller of the regex
engine shouldn't have to worry about whether to call intuit() or
regexec(), and to know to set $& in the intuit-only case.

So, move all the intuit-calling and $& setting into regexec itself.
This is cleaner, and will also shortly allow us to enable intuit-only
matches in pp_subst() too. After this change, the code above looks like
(in its entirety):

    if (!regexec(..., r_flags))
        goto nope;

    ...

There, isn't that nicer?

1 files changed, 30 insertions, 0 deletions

diff --git a/regexec.c b/regexec.c
index dc4d288c2e..5a06f3b8b4 100644
--- a/regexec.c
+++ b/regexec.c
@@ -2234,6 +2234,36 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
         "Matching");
     );
 
+    if ((RX_EXTFLAGS(rx) & RXf_USE_INTUIT)
+        && !(flags & REXEC_CHECKED))
+    {
+	stringarg = re_intuit_start(rx, sv, strbeg, stringarg, strend,
+                                    flags, NULL);
+	if (!stringarg)
+	    return 0;
+
+	if (RX_EXTFLAGS(rx) & RXf_CHECK_ALL) {
+            /* we can match based purely on the result of INTUIT.
+             * Set up captures etc just for $& and $-[0]
+             * (an intuit-only match wont have $1,$2,..) */
+            assert(!prog->nparens);
+            /* match via INTUIT shouldn't have any captures.
+             * Let @-, @+, $^N know */
+            prog->lastparen = prog->lastcloseparen = 0;
+            RX_MATCH_UTF8_set(rx, utf8_target);
+            if ( !(flags & REXEC_NOT_FIRST) )
+                Perl_reg_set_capture_string(aTHX_ rx,
+                                        strbeg, strend,
+                                        sv, flags, utf8_target);
+
+            prog->offs[0].start = stringarg - strbeg;
+            prog->offs[0].end = utf8_target
+                ? (char*)utf8_hop((U8*)stringarg, prog->minlenret) - strbeg
+                : stringarg - strbeg + prog->minlenret;
+	    return 1;
+        }
+    }
+
 
     /* at the end of this function, we'll do a LEAVE_SCOPE(oldsave),
      * which will call destuctors to reset PL_regmatch_state, free higher