From: Dave Mitchell <davem@fdisolutions.com>
Date: Fri, 14 Jul 2006 11:50:37 +0000 (+0000)
Subject: remove regex postive super-linear cache code
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=3298f2576bd4718b372a9e51e1043fdf2c0a56ab;p=p5sagit%2Fp5-mst-13.2.git

remove regex postive super-linear cache code
(it wasn't actually achieving anything)

p4raw-id: //depot/perl@28571
---

diff --git a/regexec.c b/regexec.c
index a13449f..44f893e 100644
--- a/regexec.c
+++ b/regexec.c
@@ -2099,54 +2099,14 @@ S_regtry(pTHX_ const regmatch_info *reginfo, char *startpos)
 #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 (st->u.whilem.cache_offset | st->u.whilem.cache_bit) { \
-	if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) { \
-	    PL_reg_poscache[0] |= (1<<POSCACHE_SUCCESS) | (1<<POSCACHE_SEEN); \
-	    PL_reg_poscache[st->u.whilem.cache_offset] |= (1<<st->u.whilem.cache_bit); \
-	} \
-        else if (PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS)) { \
-	    PL_reg_poscache[st->u.whilem.cache_offset] |= (1<<st->u.whilem.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[st->u.whilem.cache_offset] &= ~(1<<st->u.whilem.cache_bit); \
-	} \
-    } \
-    sayYES; \
-} STMT_END
-
 #define CACHEsayNO STMT_START { \
-    if (st->u.whilem.cache_offset | st->u.whilem.cache_bit) { \
-	if (!(PL_reg_poscache[0] & (1<<POSCACHE_SEEN))) { \
-	    PL_reg_poscache[0] |= (1<<POSCACHE_SEEN); \
-	    PL_reg_poscache[st->u.whilem.cache_offset] |= (1<<st->u.whilem.cache_bit); \
-	} \
-        else if (!(PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))) { \
-	    PL_reg_poscache[st->u.whilem.cache_offset] |= (1<<st->u.whilem.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[st->u.whilem.cache_offset] &= ~(1<<st->u.whilem.cache_bit); \
-	} \
-    } \
+    if (st->u.whilem.cache_offset | st->u.whilem.cache_bit) \
+       PL_reg_poscache[st->u.whilem.cache_offset] |= \
+	    (1<<st->u.whilem.cache_bit); \
     sayNO; \
 } STMT_END
 
+
 /* this is used to determine how far from the left messages like
    'failed...' are printed. Currently 29 makes these messages line
    up with the opcode they refer to. Earlier perls used 25 which
@@ -3587,7 +3547,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		    PL_reg_leftiter = PL_reg_maxiter;
 		}
 		if (PL_reg_leftiter-- == 0) {
-		    const I32 size = (PL_reg_maxiter + 7 + POSCACHE_START)/8;
+		    const I32 size = (PL_reg_maxiter + 7)/8;
 		    if (PL_reg_poscache) {
 			if ((I32)PL_reg_poscache_size < size) {
 			    Renew(PL_reg_poscache, size, char);
@@ -3608,7 +3568,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		if (PL_reg_leftiter < 0) {
 		    st->u.whilem.cache_offset = locinput - PL_bostr;
 
-		    st->u.whilem.cache_offset = (scan->flags & 0xf) - 1 + POSCACHE_START
+		    st->u.whilem.cache_offset = (scan->flags & 0xf) - 1
 			    + st->u.whilem.cache_offset * (scan->flags>>4);
 		    st->u.whilem.cache_bit = st->u.whilem.cache_offset % 8;
 		    st->u.whilem.cache_offset /= 8;
@@ -3618,12 +3578,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 				      "%*s  already tried at this position...\n",
 				      REPORT_CODE_OFF+PL_regindent*2, "")
 			);
-			if (PL_reg_poscache[0] & (1<<POSCACHE_SUCCESS))
-			    /* cache records success */
-			    sayYES;
-			else
-			    /* cache records failure */
-			    sayNO_SILENT;
+			sayNO; /* cache records failure */
 		    }
 		}
 		}
@@ -3642,7 +3597,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		    st->cc = st->u.whilem.savecc;
 		    if (result) {
 			regcpblow(st->u.whilem.cp);
-			CACHEsayYES;	/* All done. */
+			sayYES;	/* All done. */
 		    }
 		    REGCP_UNWIND(st->u.whilem.lastcp);
 		    regcppop(rex);
@@ -3675,7 +3630,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		    /*** all unsaved local vars undefined at this point */
 		    if (result) {
 			regcpblow(st->u.whilem.cp);
-			CACHEsayYES;
+			sayYES;
 		    }
 		    REGCP_UNWIND(st->u.whilem.lastcp);
 		    regcppop(rex);
@@ -3695,7 +3650,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		    /*** all unsaved local vars undefined at this point */
 		    if (result) {
 			regcpblow(st->u.whilem.cp);
-			CACHEsayYES;
+			sayYES;
 		    }
 		    REGCP_UNWIND(st->u.whilem.lastcp);
 		    regcppop(rex);	/* Restore some previous $<digit>s? */
@@ -3723,7 +3678,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog)
 		/*** all unsaved local vars undefined at this point */
 		st->cc = st->u.whilem.savecc;
 		if (result)
-		    CACHEsayYES;
+		    sayYES;
 		if (st->cc->u.curlyx.outercc)
 		    st->cc->u.curlyx.outercc->u.curlyx.cur = st->ln;
 		st->cc->u.curlyx.cur = n - 1;
diff --git a/t/op/re_tests b/t/op/re_tests
index 3e11a91..d35104f 100644
--- a/t/op/re_tests
+++ b/t/op/re_tests
@@ -972,3 +972,7 @@ x(?#	x	c	-	Sequence (?#... not terminated
 X(A|B||C|D)Y	XXXYYY	y	$&	XY	# Trie w/ NOTHING
 (?i:X([A]|[B]|y[Y]y|[D]|)Y)	XXXYYYB	y	$&	XY	# Trie w/ NOTHING
 ^([a]{1})*$	aa	y	$1	a
+a(?!b(?!c))(..)	abababc	y	$1	bc	# test nested negatives
+a(?!b(?=a))(..)	abababc	y	$1	bc	# test nested lookaheads
+a(?!b(?!c(?!d(?!e))))...(.)	abxabcdxabcde	y	$1	e
+X(?!b+(?!(c+)*(?!(c+)*d))).*X	aXbbbbbbbcccccccccccccaaaX	y	-	-