From 2779dcf1a3ceec167d36a36fc44de44737edcc4c Mon Sep 17 00:00:00 2001
From: Ilya Zakharevich <ilya@math.berkeley.edu>
Date: Wed, 4 Mar 1998 18:55:54 -0500
Subject: [PATCH 1/1] [5.004_61 PATCH] Make incompatible changes to RE engine
 NOW

p4raw-id: //depot/perl@785
---
 op.c      |  2 +-
 proto.h   |  2 +-
 regcomp.c | 11 +++++++++--
 regexp.h  | 23 +++++++++++++++++++++++
 util.c    |  2 +-
 5 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/op.c b/op.c
index 28e05f1..907e975 100644
--- a/op.c
+++ b/op.c
@@ -4261,7 +4261,7 @@ ck_index(OP *o)
     if (o->op_flags & OPf_KIDS) {
 	OP *kid = cLISTOPo->op_first->op_sibling;	/* get past pushmark */
 	if (kid && kid->op_type == OP_CONST)
-	    fbm_compile(((SVOP*)kid)->op_sv);
+	    fbm_compile(((SVOP*)kid)->op_sv, 0);
     }
     return ck_fun(o);
 }
diff --git a/proto.h b/proto.h
index 4df73df..037e154 100644
--- a/proto.h
+++ b/proto.h
@@ -137,7 +137,7 @@ void	dump_op _((OP* arg));
 void	dump_pm _((PMOP* pm));
 void	dump_packsubs _((HV* stash));
 void	dump_sub _((GV* gv));
-void	fbm_compile _((SV* sv));
+void	fbm_compile _((SV* sv, U32 flags));
 char*	fbm_instr _((unsigned char* big, unsigned char* bigend, SV* littlesv));
 #ifdef USE_THREADS
 PADOFFSET	find_threadsv _((char *name));
diff --git a/regcomp.c b/regcomp.c
index 4a46c7a..11358db 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -812,6 +812,11 @@ pregcomp(char *exp, char *xend, PMOP *pm)
     r->regstclass = NULL;
     r->naughty = regnaughty >= 10;	/* Probably an expensive pattern. */
     scan = r->program + 1;		/* First BRANCH. */
+
+    /* XXXX To minimize changes to RE engine we always allocate
+       3-units-long substrs field. */
+    Newz(1004, r->substrs, 1, struct reg_substr_data);
+
     if (OP(scan) != BRANCH) {	/* Only one top-level choice. */
 	scan_data_t data;
 	I32 fake;
@@ -906,7 +911,7 @@ pregcomp(char *exp, char *xend, PMOP *pm)
 	    r->float_substr = data.longest_float;
 	    r->float_min_offset = data.offset_float_min;
 	    r->float_max_offset = data.offset_float_max;
-	    fbm_compile(r->float_substr);
+	    fbm_compile(r->float_substr, 0);
 	    BmUSEFUL(r->float_substr) = 100;
 	    if (data.flags & SF_FL_BEFORE_EOL /* Cannot have SEOL and MULTI */
 		&& (!(data.flags & SF_FL_BEFORE_MEOL)
@@ -926,7 +931,7 @@ pregcomp(char *exp, char *xend, PMOP *pm)
 		    || (regflags & PMf_MULTILINE)))) {
 	    r->anchored_substr = data.longest_fixed;
 	    r->anchored_offset = data.offset_fixed;
-	    fbm_compile(r->anchored_substr);
+	    fbm_compile(r->anchored_substr, 0);
 	    BmUSEFUL(r->anchored_substr) = 100;
 	    if (data.flags & SF_FIX_BEFORE_EOL /* Cannot have SEOL and MULTI */
 		&& (!(data.flags & SF_FIX_BEFORE_MEOL)
@@ -2565,6 +2570,8 @@ pregfree(struct regexp *r)
 	Safefree(r->precomp);
     if (r->subbase)
 	Safefree(r->subbase);
+    if (r->substrs)
+	Safefree(r->substrs);
     if (r->anchored_substr)
 	SvREFCNT_dec(r->anchored_substr);
     if (r->float_substr)
diff --git a/regexp.h b/regexp.h
index 7137ffc..cb6b0c6 100644
--- a/regexp.h
+++ b/regexp.h
@@ -23,6 +23,16 @@ struct reg_data {
     void* data[1];
 };
 
+struct reg_substr_datum {
+    I32 min_offset;
+    I32 max_offset;
+    SV *substr;
+};
+
+struct reg_substr_data {
+    struct reg_substr_datum data[3];	/* Actual array */
+};
+
 typedef struct regexp {
 	I32 refcnt;
 	char **startp;
@@ -39,6 +49,7 @@ typedef struct regexp {
 	U16 naughty;		/* how exponential is this pattern? */
 	U16 reganch;		/* Internal use only +
 				   Tainted information used by regexec? */
+#if 0
         SV *anchored_substr;	/* Substring at fixed position wrt start. */
 	I32 anchored_offset;	/* Position of it. */
         SV *float_substr;	/* Substring at variable position wrt start. */
@@ -47,10 +58,22 @@ typedef struct regexp {
         SV *check_substr;	/* Substring to check before matching. */
         I32 check_offset_min;	/* Offset of the above. */
         I32 check_offset_max;	/* Offset of the above. */
+#else
+        struct reg_substr_data *substrs;
+#endif
         struct reg_data *data;	/* Additional data. */
 	regnode program[1];	/* Unwarranted chumminess with compiler. */
 } regexp;
 
+#define anchored_substr substrs->data[0].substr
+#define anchored_offset substrs->data[0].min_offset
+#define float_substr substrs->data[1].substr
+#define float_min_offset substrs->data[1].min_offset
+#define float_max_offset substrs->data[1].max_offset
+#define check_substr substrs->data[2].substr
+#define check_offset_min substrs->data[2].min_offset
+#define check_offset_max substrs->data[2].max_offset
+
 #define ROPT_ANCH		(ROPT_ANCH_BOL|ROPT_ANCH_MBOL|ROPT_ANCH_GPOS)
 #define ROPT_ANCH_SINGLE	(ROPT_ANCH_BOL|ROPT_ANCH_GPOS)
 #define ROPT_ANCH_BOL	 	1
diff --git a/util.c b/util.c
index 770aa29..6cb8e69 100644
--- a/util.c
+++ b/util.c
@@ -891,7 +891,7 @@ mem_collxfrm(const char *s, STRLEN len, STRLEN *xlen)
 #endif /* USE_LOCALE_COLLATE */
 
 void
-fbm_compile(SV *sv)
+fbm_compile(SV *sv, U32 flags /* not used yet */)
 {
     register unsigned char *s;
     register unsigned char *table;
-- 
1.8.3.1