Change 33243 by [EMAIL PROTECTED] on 2008/02/06 23:52:16
Restore the regex positive super-linear cache, as it turns out that
some patterns do actually benefit from it. (See
http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2008-01/msg01314.html )
Reverses the code change of 30620 (the tests it added still pass):
Integrate:
[ 28571]
remove regex postive super-linear cache code
(it wasn't actually achieving anything)
Affected files ...
... //depot/maint-5.8/perl/regexec.c#102 edit
Differences ...
==== //depot/maint-5.8/perl/regexec.c#102 (text) ====
Index: perl/regexec.c
--- perl/regexec.c#101~33204~ 2008-02-02 10:16:39.000000000 -0800
+++ perl/regexec.c 2008-02-06 15:52:16.000000000 -0800
@@ -1957,10 +1957,51 @@
#define sayNO_SILENT goto do_no
#define saySAME(x) if (x) goto yes; else goto no
+#define POSCACHE_SUCCESS 0 /* caching success rather than failure */
+#define POSCACHE_SEEN 1 /* we know what we're caching */
+#define POSCACHE_START 2 /* the real cache: this bit maps to pos 0 */
+
+#define CACHEsayYES STMT_START { \
+ if (cache_offset | cache_bit) { \
+ if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) { \
+ PL_reg_poscache[0] |= (1<<POSCACHE_SUCCESS) | (1<<POSCACHE_SEEN); \
+ PL_reg_poscache[cache_offset] |= (1<<cache_bit); \
+ } \
+ else if (PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS)) { \
+ PL_reg_poscache[cache_offset] |= (1<<cache_bit); \
+ } \
+ else { \
+ /* cache records failure, but this is success */ \
+ DEBUG_r( \
+ PerlIO_printf(Perl_debug_log, \
+ "%*s (remove success from failure cache)\n", \
+ REPORT_CODE_OFF+PL_regindent*2, "") \
+ ); \
+ PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+ } \
+ } \
+ sayYES; \
+} STMT_END
+
#define CACHEsayNO STMT_START { \
- if (cache_offset | cache_bit) \
- PL_reg_poscache[cache_offset] |= \
- (1<<cache_bit); \
+ if (cache_offset | cache_bit) { \
+ if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) { \
+ PL_reg_poscache[0] |= (1<<POSCACHE_SEEN); \
+ PL_reg_poscache[cache_offset] |= (1<<cache_bit); \
+ } \
+ else if (!(PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
+ PL_reg_poscache[cache_offset] |= (1<<cache_bit); \
+ } \
+ else { \
+ /* cache records success, but this is failure */ \
+ DEBUG_r( \
+ PerlIO_printf(Perl_debug_log, \
+ "%*s (remove failure from success cache)\n", \
+ REPORT_CODE_OFF+PL_regindent*2, "") \
+ ); \
+ PL_reg_poscache[cache_offset] &= ~(1<<cache_bit); \
+ } \
+ } \
sayNO; \
} STMT_END
@@ -2949,7 +2990,7 @@
PL_reg_leftiter = PL_reg_maxiter;
}
if (PL_reg_leftiter-- == 0) {
- const I32 size = (PL_reg_maxiter + 7)/8;
+ const I32 size = (PL_reg_maxiter + 7 + POSCACHE_START)/8;
if (PL_reg_poscache) {
if ((I32)PL_reg_poscache_size < size) {
Renew(PL_reg_poscache, size, char);
@@ -2970,7 +3011,7 @@
if (PL_reg_leftiter < 0) {
cache_offset = locinput - PL_bostr;
- cache_offset = (scan->flags & 0xf) - 1
+ cache_offset = (scan->flags & 0xf) - 1 + POSCACHE_START
+ cache_offset * (scan->flags>>4);
cache_bit = cache_offset % 8;
cache_offset /= 8;
@@ -2980,7 +3021,12 @@
"%*s already tried at this
position...\n",
REPORT_CODE_OFF+PL_regindent*2, "")
);
- sayNO; /* cache records failure */
+ if (PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))
+ /* cache records success */
+ sayYES;
+ else
+ /* cache records failure */
+ sayNO_SILENT;
}
}
}
@@ -2995,7 +3041,7 @@
REGCP_SET(lastcp);
if (regmatch(cc->next)) {
regcpblow(cp);
- sayYES; /* All done. */
+ CACHEsayYES; /* All done. */
}
REGCP_UNWIND(lastcp);
regcppop();
@@ -3027,7 +3073,7 @@
REGCP_SET(lastcp);
if (regmatch(cc->scan)) {
regcpblow(cp);
- sayYES;
+ CACHEsayYES;
}
REGCP_UNWIND(lastcp);
regcppop();
@@ -3045,7 +3091,7 @@
REGCP_SET(lastcp);
if (regmatch(cc->scan)) {
regcpblow(cp);
- sayYES;
+ CACHEsayYES;
}
REGCP_UNWIND(lastcp);
regcppop(); /* Restore some previous $<digit>s? */
@@ -3069,7 +3115,7 @@
if (PL_regcc)
ln = PL_regcc->cur;
if (regmatch(cc->next))
- sayYES;
+ CACHEsayYES;
if (PL_regcc)
PL_regcc->cur = ln;
PL_regcc = cc;
End of Patch.
