regex substrs: record index of check substr

Currently prog->substrs->data[] is a 3 element array of structures.
Elements 0 and 1 record the longest anchored and floating substrings,
while element 2 ('check'), is a copy of the longest of 0 and 1.

Record in a new field, prog->substrs->check_ix, the index of which element
was copied. (Eventually I intend to remove the copy altogether.)

Also for the anchored substr, set max_offset equal to min offset.
Previously it was left as zero and ignored, although if copied to check,
the check copy of max *was* set equal to min. Having this always set will
allow us to make the code simpler.

1 files changed, 4 insertions, 0 deletions

diff --git a/regcomp.c b/regcomp.c
index a6572523f8..a82171a9b2 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -6953,6 +6953,7 @@ reStudy:
         /* A temporary algorithm prefers floated substr to fixed one to dig
          * more info. */
 	if (longest_fixed_length > longest_float_length) {
+	    r->substrs->check_ix = 0;
 	    r->check_end_shift = r->anchored_end_shift;
 	    r->check_substr = r->anchored_substr;
 	    r->check_utf8 = r->anchored_utf8;
@@ -6961,6 +6962,7 @@ reStudy:
                 r->intflags |= PREGf_NOSCAN;
 	}
 	else {
+	    r->substrs->check_ix = 1;
 	    r->check_end_shift = r->float_end_shift;
 	    r->check_substr = r->float_substr;
 	    r->check_utf8 = r->float_utf8;
@@ -6972,6 +6974,8 @@ reStudy:
 	    if (SvTAIL(r->check_substr ? r->check_substr : r->check_utf8))
 		r->extflags |= RXf_INTUIT_TAIL;
 	}
+        r->substrs->data[0].max_offset = r->substrs->data[0].min_offset;
+
 	/* XXX Unneeded? dmq (shouldn't as this is handled elsewhere)
 	if ( (STRLEN)minlen < longest_float_length )
             minlen= longest_float_length;