Change 27598 by [EMAIL PROTECTED] on 2006/03/24 23:05:11
make S_regmatch() iterative rather than recursive.
Goodbye stack-bustng regexes!
Affected files ...
... //depot/perl/regexec.c#382 edit
Differences ...
==== //depot/perl/regexec.c#382 (text) ====
Index: perl/regexec.c
--- perl/regexec.c#381~27569~ 2006-03-22 08:05:16.000000000 -0800
+++ perl/regexec.c 2006-03-24 15:05:11.000000000 -0800
@@ -296,7 +296,7 @@
#define regcpblow(cp) LEAVE_SCOPE(cp) /* Ignores regcppush()ed data. */
-#define TRYPAREN(paren, n, input) { \
+#define TRYPAREN(paren, n, input, where) { \
if (paren) { \
if (n) { \
PL_regstartp[paren] = HOPc(input, -1) - PL_bostr; \
@@ -305,7 +305,8 @@
else \
PL_regendp[paren] = -1; \
} \
- if (regmatch(next)) \
+ REGMATCH(next, where); \
+ if (result) \
sayYES; \
if (paren && n) \
PL_regendp[paren] = -1; \
@@ -1646,8 +1647,6 @@
PERL_UNUSED_ARG(data);
RX_MATCH_UTF8_set(prog,do_utf8);
- PL_regcc = 0;
-
cache_re(prog);
#ifdef DEBUGGING
PL_regnarrate = DEBUG_r_TEST;
@@ -2313,6 +2312,69 @@
#define TRIE_INITAL_ACCEPT_BUFFLEN 4;
+/* simulate a recursive call to regmatch */
+
+#define REGMATCH(ns, where) \
+ new_scan = (ns); \
+ resume_state = resume_##where; \
+ goto start_recurse; \
+ resume_point_##where:
+
+typedef enum {
+ resume_TRIE1,
+ resume_TRIE2,
+ resume_CURLYX,
+ resume_WHILEM1,
+ resume_WHILEM2,
+ resume_WHILEM3,
+ resume_WHILEM4,
+ resume_WHILEM5,
+ resume_WHILEM6,
+ resume_CURLYM1,
+ resume_CURLYM2,
+ resume_CURLYM3,
+ resume_CURLYM4,
+ resume_IFMATCH,
+ resume_PLUS1,
+ resume_PLUS2,
+ resume_PLUS3,
+ resume_PLUS4,
+ resume_END
+} resume_states;
+
+
+struct regmatch_state {
+ struct regmatch_state *prev_state;
+ resume_states resume_state;
+ regnode *scan;
+ regnode *next;
+ bool minmod;
+ bool sw;
+ int logical;
+ I32 unwind;
+ CURCUR *cc;
+ char *locinput;
+
+ I32 n;
+ I32 ln;
+ I32 c1, c2, paren;
+ CHECKPOINT cp, lastcp;
+ CURCUR *oldcc;
+ char *lastloc;
+ I32 cache_offset, cache_bit;
+ I32 curlym_l;
+ I32 matches;
+ I32 maxwanted;
+ char *e;
+ char *old;
+ int count;
+ re_cc_state *cur_call_cc;
+ regexp *end_re;
+ reg_trie_accepted *accept_buff;
+ U32 accepted;
+
+ re_cc_state *reg_call_cc; /* saved value of PL_reg_call_cc */
+};
/*
- regmatch - main matching routine
@@ -2327,44 +2389,154 @@
/* [lwall] I've hoisted the register declarations to the outer block in order
to
* maybe save a little bit of pushing and popping on the stack. It also takes
* advantage of machines that use a register save mask on subroutine entry.
+ *
+ * This function used to be heavily recursive, but since this had the
+ * effect of blowing the CPU stack on complex regexes, it has been
+ * restructured to be iterative, and to save state onto the heap rather
+ * than the stack. Essentially whereever regmatch() used to be called, it
+ * pushes the current state, notes where to return, then jumps back into
+ * the main loop.
+ *
+ * Originally the structure of this function used to look something like
+
+ S_regmatch() {
+ int a = 1, b = 2;
+ ...
+ while (scan != NULL) {
+ ...
+ switch (OP(scan)) {
+ case FOO: {
+ int local = 3;
+ ...
+ if (regmatch(...)) // recurse
+ goto yes;
+ }
+ ...
+ }
+ }
+ yes:
+ return 1;
+ }
+
+ * Now it looks something like this:
+
+ struct regmatch_state {
+ int a, b, local;
+ int resume_state;
+ };
+
+ S_regmatch() {
+ int a = 1, b = 2;
+ int local;
+ ...
+ while (scan != NULL) {
+ ...
+ switch (OP(scan)) {
+ case FOO: {
+ local = 3;
+ ...
+ resume_state = resume_FOO;
+ new_scan = ...;
+ goto start_recurse;
+ resume_point_FOO:
+
+ if (result) // recurse
+ goto yes;
+ }
+ ...
+ }
+ start_recurse:
+ ...push a, b, local onto the heap
+ a = 1; b = 2;
+ scan = new_scan;
+ }
+ yes:
+ result = 1;
+ if (states pushed on heap) {
+ ... restore a, b, local from heap
+ switch (resume_state) {
+ case resume_FOO:
+ goto resume_point_FOO;
+ ...
+ }
+ }
+ return result
+ }
+
+ * WARNING: this means that any line in this function that contains a
+ * REGMATCH() or TRYPAREN() is actually simulating a recursive call to
+ * regmatch() using gotos instead. Thus the values of any local variables
+ * not saved in the regmatch_state structure will have been lost when
+ * execution resumes on the next line .
*/
+
+
STATIC I32 /* 0 failure, 1 success */
S_regmatch(pTHX_ regnode *prog)
{
dVAR;
+ register const bool do_utf8 = PL_reg_match_utf8;
+ const U32 uniflags = ckWARN(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY;
+
+ /************************************************************
+ * the following variabes are saved and restored on each fake
+ * recursive call to regmatch:
+ *
+ * The first ones contain state that needs to be maintained
+ * across the main while loop: */
+
+ struct regmatch_state *prev_state = NULL; /* stack of pushed states */
+ resume_states resume_state; /* where to jump to on return */
register regnode *scan; /* Current node. */
regnode *next; /* Next node. */
- regnode *inner; /* Next node in internal branch. */
- register I32 nextchr; /* renamed nextchr - nextchar colides with
- function of same name */
- register I32 n; /* no or next */
- register I32 ln = 0; /* len or last */
- register char *s = NULL; /* operand or save */
+ bool minmod = 0; /* the next {n.m} is a {n,m}? */
+ bool sw = 0; /* the condition value in (?(cond)a|b) */
+ int logical = 0;
+ I32 unwind = 0; /* savestack index of current unwind block */
+ CURCUR *cc = NULL; /* current innermost curly struct */
register char *locinput = PL_reginput;
- register I32 c1 = 0, c2 = 0, paren; /* case fold search, parenth */
- int minmod = 0, sw = 0, logical = 0;
- I32 unwind = 0;
-#if 0
- I32 firstcp = PL_savestack_ix;
-#endif
- register const bool do_utf8 = PL_reg_match_utf8;
-#ifdef DEBUGGING
- SV * const dsv0 = PERL_DEBUG_PAD_ZERO(0);
- SV * const dsv1 = PERL_DEBUG_PAD_ZERO(1);
- SV * const dsv2 = PERL_DEBUG_PAD_ZERO(2);
-
- SV *re_debug_flags = NULL;
-#endif
- U32 uniflags = ckWARN(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY;
+ /* while the rest of these are local to an individual branch, and
+ * have only been hoisted into this outer scope to allow for saving and
+ * restoration - thus they can be safely reused in other branches.
+ * Note that they are only initialized here to silence compiler
+ * warnings :-( */
- GET_RE_DEBUG_FLAGS;
+ register I32 n = 0; /* no or next */
+ register I32 ln = 0; /* len or last */
+ register I32 c1 = 0, c2 = 0, paren = 0; /* case fold search, parenth */
+ CHECKPOINT cp = 0; /* remember current savestack indexes */
+ CHECKPOINT lastcp = 0;
+ CURCUR *oldcc = NULL; /* tmp copy of cc */
+ char *lastloc = NULL; /* Detection of 0-len. */
+ I32 cache_offset = 0;
+ I32 cache_bit = 0;
+ I32 curlym_l = 0;
+ I32 matches = 0;
+ I32 maxwanted = 0;
+ char *e = NULL;
+ char *old = NULL;
+ int count = 0;
+ re_cc_state *cur_call_cc = NULL;
+ regexp *end_re = NULL;
+ reg_trie_accepted *accept_buff = NULL;
+ U32 accepted = 0; /* how many accepting states we have seen */
+
+ /************************************************************
+ * these variables are NOT saved: */
+
+ register I32 nextchr; /* is always set to UCHARAT(locinput) */
+ regnode *new_scan; /* node to begin exedcution at when recursing */
+ bool result; /* return value of S_regmatch */
+ regnode *inner; /* Next node in internal branch. */
+
#ifdef DEBUGGING
+ SV *re_debug_flags = NULL;
+ GET_RE_DEBUG_FLAGS;
PL_regindent++;
#endif
-
/* Note that nextchr is a byte even in UTF */
nextchr = UCHARAT(locinput);
scan = prog;
@@ -2401,17 +2573,18 @@
{
const char * const s0 =
do_utf8 && OP(scan) != CANY ?
- pv_uni_display(dsv0, (U8*)(locinput - pref_len),
+ pv_uni_display(PERL_DEBUG_PAD(0), (U8*)(locinput - pref_len),
pref0_len, 60, UNI_DISPLAY_REGEX) :
locinput - pref_len;
const int len0 = do_utf8 ? strlen(s0) : pref0_len;
const char * const s1 = do_utf8 && OP(scan) != CANY ?
- pv_uni_display(dsv1, (U8*)(locinput - pref_len + pref0_len),
+ pv_uni_display(PERL_DEBUG_PAD(1),
+ (U8*)(locinput - pref_len + pref0_len),
pref_len - pref0_len, 60, UNI_DISPLAY_REGEX) :
locinput - pref_len + pref0_len;
const int len1 = do_utf8 ? strlen(s1) : pref_len - pref0_len;
const char * const s2 = do_utf8 && OP(scan) != CANY ?
- pv_uni_display(dsv2, (U8*)locinput,
+ pv_uni_display(PERL_DEBUG_PAD(2), (U8*)locinput,
PL_regeol - locinput, 60, UNI_DISPLAY_REGEX) :
locinput;
const int len2 = do_utf8 ? strlen(s2) : l;
@@ -2530,18 +2703,16 @@
STRLEN foldlen = 0;
U8 *uscan = (U8*)NULL;
STRLEN bufflen=0;
+ SV *sv_accept_buff = NULL;
const enum { trie_plain, trie_utf8, trie_uft8_fold }
trie_type = do_utf8 ?
(OP(scan) == TRIE ? trie_utf8 : trie_uft8_fold)
: trie_plain;
- int gotit = 0;
- /* accepting states we have traversed */
- SV *sv_accept_buff = NULL;
- reg_trie_accepted *accept_buff = NULL;
reg_trie_data *trie; /* what trie are we using right now */
- U32 accepted = 0; /* how many accepting states we have seen */
+ accepted = 0; /* how many accepting states we have seen */
+ result = 0;
trie = (reg_trie_data*)PL_regdata->data[ ARG( scan ) ];
while ( state && uc <= (U8*)PL_regeol ) {
@@ -2679,14 +2850,15 @@
as we wont be using accept_buff again. */
FREETMPS;
LEAVE;
- gotit = regmatch( scan + NEXT_OFF( scan ) );
+ REGMATCH(scan + NEXT_OFF(scan), TRIE1);
+ /*** all unsaved local vars undefined at this point */
} else {
DEBUG_EXECUTE_r(
PerlIO_printf( Perl_debug_log,"%*s %sgot %"IVdf"
possible matches%s\n",
REPORT_CODE_OFF + PL_regindent * 2, "",
PL_colors[4], (IV)accepted,
PL_colors[5] );
);
- while ( !gotit && accepted-- ) {
+ while ( !result && accepted-- ) {
U32 best = 0;
U32 cur;
for( cur = 1 ; cur <= accepted ; cur++ ) {
@@ -2723,22 +2895,23 @@
all until I can be sure.
*/
SAVETMPS;
- gotit = regmatch( scan + NEXT_OFF( scan ) ) ;
+ REGMATCH(scan + NEXT_OFF(scan), TRIE2);
+ /*** all unsaved local vars undefined at this point */
FREETMPS;
}
FREETMPS;
LEAVE;
}
- if ( gotit ) {
+ if (result) {
sayYES;
} else {
sayNO;
}
}
/* unreached codepoint */
- case EXACT:
- s = STRING(scan);
+ case EXACT: {
+ char *s = STRING(scan);
ln = STR_LEN(scan);
if (do_utf8 != UTF) {
/* The target and the pattern have differing utf8ness. */
@@ -2788,11 +2961,12 @@
locinput += ln;
nextchr = UCHARAT(locinput);
break;
+ }
case EXACTFL:
PL_reg_flags |= RF_tainted;
/* FALL THROUGH */
- case EXACTF:
- s = STRING(scan);
+ case EXACTF: {
+ char *s = STRING(scan);
ln = STR_LEN(scan);
if (do_utf8 || UTF) {
@@ -2836,6 +3010,7 @@
locinput += ln;
nextchr = UCHARAT(locinput);
break;
+ }
case ANYOF:
if (do_utf8) {
STRLEN inclasslen = PL_regeol - locinput;
@@ -3078,7 +3253,8 @@
PL_reg_flags |= RF_tainted;
/* FALL THROUGH */
case REF:
- case REFF:
+ case REFF: {
+ char *s;
n = ARG(scan); /* which paren pair */
ln = PL_regstartp[n];
PL_reg_leftiter = PL_reg_maxiter; /* Void cache */
@@ -3135,6 +3311,7 @@
locinput += ln;
nextchr = UCHARAT(locinput);
break;
+ }
case NOTHING:
case TAIL:
@@ -3176,7 +3353,6 @@
regexp *re;
MAGIC *mg = NULL;
re_cc_state state;
- CHECKPOINT cp, lastcp;
int toggleutf;
register SV *sv;
@@ -3223,10 +3399,10 @@
);
state.node = next;
state.prev = PL_reg_call_cc;
- state.cc = PL_regcc;
+ state.cc = cc;
state.re = PL_reg_re;
- PL_regcc = 0;
+ cc = 0;
cp = regcppush(0); /* Save *all* the positions. */
REGCP_SET(lastcp);
@@ -3243,6 +3419,7 @@
/* XXXX This is too dramatic a measure... */
PL_reg_maxiter = 0;
+ /* XXX the only recursion left in regmatch() */
if (regmatch(re->program + 1)) {
/* Even though we succeeded, we need to restore
global variables, since we may be wrapped inside
@@ -3250,7 +3427,7 @@
/* XXXX Do this only if SUSPENDed? */
PL_reg_call_cc = state.prev;
- PL_regcc = state.cc;
+ cc = state.cc;
PL_reg_re = state.re;
cache_re(PL_reg_re);
if (toggleutf) PL_reg_flags ^= RF_utf8;
@@ -3267,7 +3444,7 @@
REGCP_UNWIND(lastcp);
regcppop();
PL_reg_call_cc = state.prev;
- PL_regcc = state.cc;
+ cc = state.cc;
PL_reg_re = state.re;
cache_re(PL_reg_re);
if (toggleutf) PL_reg_flags ^= RF_utf8;
@@ -3319,15 +3496,15 @@
logical = scan->flags;
break;
/*******************************************************************
- PL_regcc contains infoblock about the innermost (...)* loop, and
+ cc contains infoblock about the innermost (...)* loop, and
a pointer to the next outer infoblock.
Here is how Y(A)*Z is processed (if it is compiled into CURLYX/WHILEM):
- 1) After matching X, regnode for CURLYX is processed;
+ 1) After matching Y, regnode for CURLYX is processed;
- 2) This regnode creates infoblock on the stack, and calls
- regmatch() recursively with the starting point at WHILEM node;
+ 2) This regnode mallocs an infoblock, and calls regmatch() recursively
+ with the starting point at WHILEM node;
3) Each hit of WHILEM node tries to match A and Z (in the order
depending on the current iteration, min/max of {min,max} and
@@ -3337,9 +3514,9 @@
4) After A matches, the same WHILEM node is hit again.
- 5) Each time WHILEM is hit, PL_regcc is the infoblock created by CURLYX
+ 5) Each time WHILEM is hit, cc is the infoblock created by CURLYX
of the same pair. Thus when WHILEM tries to match Z, it temporarily
- resets PL_regcc, since this Y(A)*Z can be a part of some other loop:
+ resets cc, since this Y(A)*Z can be a part of some other loop:
as in (Y(A)*Z)*. If Z matches, the automaton will hit the WHILEM node
of the external loop.
@@ -3347,7 +3524,7 @@
and whatever it mentions via ->next, and additional attached trees
corresponding to temporarily unset infoblocks as in "5" above.
- In the following picture infoblocks for outer loop of
+ In the following picture, infoblocks for outer loop of
(Y(A)*?Z)*?T are denoted O, for inner I. NULL starting block
is denoted by x. The matched string is YAAZYAZT. Temporarily postponed
infoblocks are drawn below the "reset" infoblock.
@@ -3393,33 +3570,40 @@
O
I,I
*******************************************************************/
+
case CURLYX: {
- CURCUR cc;
- CHECKPOINT cp = PL_savestack_ix;
/* No need to save/restore up to this paren */
I32 parenfloor = scan->flags;
+ {
+ CURCUR *newcc;
+ Newx(newcc, 1, CURCUR);
+ oldcc = cc;
+ newcc->oldcc = cc;
+ cc = newcc;
+ }
+ cp = PL_savestack_ix;
if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */
next += ARG(next);
- cc.oldcc = PL_regcc;
- PL_regcc = &cc;
/* XXXX Probably it is better to teach regpush to support
parenfloor > PL_regsize... */
if (parenfloor > (I32)*PL_reglastparen)
parenfloor = *PL_reglastparen; /* Pessimization... */
- cc.parenfloor = parenfloor;
- cc.cur = -1;
- cc.min = ARG1(scan);
- cc.max = ARG2(scan);
- cc.scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
- cc.next = next;
- cc.minmod = minmod;
- cc.lastloc = 0;
+ cc->parenfloor = parenfloor;
+ cc->cur = -1;
+ cc->min = ARG1(scan);
+ cc->max = ARG2(scan);
+ cc->scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
+ cc->next = next;
+ cc->minmod = minmod;
+ cc->lastloc = 0;
PL_reginput = locinput;
- n = regmatch(PREVOPER(next)); /* start on the WHILEM */
+ REGMATCH(PREVOPER(next), CURLYX); /* start on the WHILEM */
+ /*** all unsaved local vars undefined at this point */
regcpblow(cp);
- PL_regcc = cc.oldcc;
- saySAME(n);
+ Safefree(cc);
+ cc = oldcc;
+ saySAME(result);
}
/* NOTREACHED */
case WHILEM: {
@@ -3432,10 +3616,9 @@
* that we can try again after backing off.
*/
- CHECKPOINT cp, lastcp;
- CURCUR* cc = PL_regcc;
- char * const lastloc = cc->lastloc; /* Detection of 0-len. */
- I32 cache_offset = 0, cache_bit = 0;
+ lastloc = cc->lastloc; /* Detection of 0-len. */
+ cache_offset = 0;
+ cache_bit = 0;
n = cc->cur + 1; /* how many we know we matched */
PL_reginput = locinput;
@@ -3451,19 +3634,22 @@
/* If degenerate scan matches "", assume scan done. */
if (locinput == cc->lastloc && n >= cc->min) {
- PL_regcc = cc->oldcc;
- if (PL_regcc)
- ln = PL_regcc->cur;
+ oldcc = cc;
+ cc = cc->oldcc;
+ if (cc)
+ ln = cc->cur;
DEBUG_EXECUTE_r(
PerlIO_printf(Perl_debug_log,
"%*s empty match detected, try continuation...\n",
REPORT_CODE_OFF+PL_regindent*2, "")
);
- if (regmatch(cc->next))
+ REGMATCH(oldcc->next, WHILEM1);
+ /*** all unsaved local vars undefined at this point */
+ cc = oldcc;
+ if (result)
sayYES;
- if (PL_regcc)
- PL_regcc->cur = ln;
- PL_regcc = cc;
+ if (cc->oldcc)
+ cc->oldcc->cur = ln;
sayNO;
}
@@ -3472,7 +3658,9 @@
if (n < cc->min) {
cc->cur = n;
cc->lastloc = locinput;
- if (regmatch(cc->scan))
+ REGMATCH(cc->scan, WHILEM2);
+ /*** all unsaved local vars undefined at this point */
+ if (result)
sayYES;
cc->cur = n - 1;
cc->lastloc = lastloc;
@@ -3533,20 +3721,23 @@
/* Prefer next over scan for minimal matching. */
if (cc->minmod) {
- PL_regcc = cc->oldcc;
- if (PL_regcc)
- ln = PL_regcc->cur;
- cp = regcppush(cc->parenfloor);
+ oldcc = cc;
+ cc = cc->oldcc;
+ if (cc)
+ ln = cc->cur;
+ cp = regcppush(oldcc->parenfloor);
REGCP_SET(lastcp);
- if (regmatch(cc->next)) {
+ REGMATCH(oldcc->next, WHILEM3);
+ /*** all unsaved local vars undefined at this point */
+ cc = oldcc;
+ if (result) {
regcpblow(cp);
CACHEsayYES; /* All done. */
}
REGCP_UNWIND(lastcp);
regcppop();
- if (PL_regcc)
- PL_regcc->cur = ln;
- PL_regcc = cc;
+ if (cc->oldcc)
+ cc->oldcc->cur = ln;
if (n >= cc->max) { /* Maximum greed exceeded? */
if (ckWARN(WARN_REGEXP) && n >= REG_INFTY
@@ -3570,7 +3761,9 @@
cc->lastloc = locinput;
cp = regcppush(cc->parenfloor);
REGCP_SET(lastcp);
- if (regmatch(cc->scan)) {
+ REGMATCH(cc->scan, WHILEM4);
+ /*** all unsaved local vars undefined at this point */
+ if (result) {
regcpblow(cp);
CACHEsayYES;
}
@@ -3588,7 +3781,9 @@
cc->cur = n;
cc->lastloc = locinput;
REGCP_SET(lastcp);
- if (regmatch(cc->scan)) {
+ REGMATCH(cc->scan, WHILEM5);
+ /*** all unsaved local vars undefined at this point */
+ if (result) {
regcpblow(cp);
CACHEsayYES;
}
@@ -3610,14 +3805,17 @@
}
/* Failed deeper matches of scan, so see if this one works. */
- PL_regcc = cc->oldcc;
- if (PL_regcc)
- ln = PL_regcc->cur;
- if (regmatch(cc->next))
+ oldcc = cc;
+ cc = cc->oldcc;
+ if (cc)
+ ln = cc->cur;
+ REGMATCH(oldcc->next, WHILEM6);
+ /*** all unsaved local vars undefined at this point */
+ cc = oldcc;
+ if (result)
CACHEsayYES;
- if (PL_regcc)
- PL_regcc->cur = ln;
- PL_regcc = cc;
+ if (cc->oldcc)
+ cc->oldcc->cur = ln;
cc->cur = n - 1;
cc->lastloc = lastloc;
CACHEsayNO;
@@ -3667,10 +3865,7 @@
break;
case CURLYM:
{
- I32 l = 0;
- I32 matches = 0;
- CHECKPOINT lastcp;
- I32 maxwanted;
+ curlym_l = matches = 0;
/* We suppose that the next guy does not need
backtracking: in particular, it is of constant non-zero length,
@@ -3691,21 +3886,23 @@
maxwanted = minmod ? ln : n;
if (maxwanted) {
while (PL_reginput < PL_regeol && matches < maxwanted) {
- if (!regmatch(scan))
+ REGMATCH(scan, CURLYM1);
+ /*** all unsaved local vars undefined at this point */
+ if (!result)
break;
- /* on first match, determine length, l */
+ /* on first match, determine length, curlym_l */
if (!matches++) {
if (PL_reg_match_utf8) {
char *s = locinput;
while (s < PL_reginput) {
- l++;
+ curlym_l++;
s += UTF8SKIP(s);
}
}
else {
- l = PL_reginput - locinput;
+ curlym_l = PL_reginput - locinput;
}
- if (l == 0) {
+ if (curlym_l == 0) {
matches = maxwanted;
break;
}
@@ -3753,19 +3950,23 @@
if (paren) {
if (ln) {
PL_regstartp[paren] =
- HOPc(PL_reginput, -l) - PL_bostr;
+ HOPc(PL_reginput, -curlym_l) - PL_bostr;
PL_regendp[paren] = PL_reginput - PL_bostr;
}
else
PL_regendp[paren] = -1;
}
- if (regmatch(next))
+ REGMATCH(next, CURLYM2);
+ /*** all unsaved local vars undefined at this point */
+ if (result)
sayYES;
REGCP_UNWIND(lastcp);
}
/* Couldn't or didn't -- move forward. */
PL_reginput = locinput;
- if (regmatch(scan)) {
+ REGMATCH(scan, CURLYM3);
+ /*** all unsaved local vars undefined at this point */
+ if (result) {
ln++;
locinput = PL_reginput;
}
@@ -3776,9 +3977,9 @@
else {
DEBUG_EXECUTE_r(
PerlIO_printf(Perl_debug_log,
- "%*s matched %"IVdf" times,
len=%"IVdf"...\n",
- (int)(REPORT_CODE_OFF+PL_regindent*2), "",
- (IV) matches, (IV)l)
+ "%*s matched %"IVdf" times, len=%"IVdf"...\n",
+ (int)(REPORT_CODE_OFF+PL_regindent*2), "",
+ (IV) matches, (IV)curlym_l)
);
if (matches >= ln) {
if (HAS_TEXT(next) || JUMPABLE(next)) {
@@ -3821,19 +4022,22 @@
);
if (paren) {
if (matches) {
- PL_regstartp[paren] = HOPc(PL_reginput, -l) -
PL_bostr;
+ PL_regstartp[paren]
+ = HOPc(PL_reginput, -curlym_l) - PL_bostr;
PL_regendp[paren] = PL_reginput - PL_bostr;
}
else
PL_regendp[paren] = -1;
}
- if (regmatch(next))
+ REGMATCH(next, CURLYM4);
+ /*** all unsaved local vars undefined at this point */
+ if (result)
sayYES;
REGCP_UNWIND(lastcp);
}
/* Couldn't or didn't -- back up. */
matches--;
- locinput = HOPc(locinput, -l);
+ locinput = HOPc(locinput, -curlym_l);
PL_reginput = locinput;
}
}
@@ -3927,16 +4131,14 @@
assume_ok_easy:
PL_reginput = locinput;
if (minmod) {
- CHECKPOINT lastcp;
minmod = 0;
if (ln && regrepeat(scan, ln) < ln)
sayNO;
locinput = PL_reginput;
REGCP_SET(lastcp);
if (c1 != -1000) {
- char *e; /* Should not check after this */
- char *old = locinput;
- int count = 0;
+ old = locinput;
+ count = 0;
if (n == REG_INFTY) {
e = PL_regeol - 1;
@@ -4006,7 +4208,8 @@
sayNO;
}
/* PL_reginput == locinput now */
- TRYPAREN(paren, ln, locinput);
+ TRYPAREN(paren, ln, locinput, PLUS1);
+ /*** all unsaved local vars undefined at this point */
PL_reginput = locinput; /* Could be reset... */
REGCP_UNWIND(lastcp);
/* Couldn't or didn't -- move forward. */
@@ -4031,14 +4234,16 @@
/* If it could work, try it. */
if (c == (UV)c1 || c == (UV)c2)
{
- TRYPAREN(paren, ln, PL_reginput);
+ TRYPAREN(paren, ln, PL_reginput, PLUS2);
+ /*** all unsaved local vars undefined at this point
*/
REGCP_UNWIND(lastcp);
}
}
/* If it could work, try it. */
else if (c1 == -1000)
{
- TRYPAREN(paren, ln, PL_reginput);
+ TRYPAREN(paren, ln, PL_reginput, PLUS3);
+ /*** all unsaved local vars undefined at this point */
REGCP_UNWIND(lastcp);
}
/* Couldn't or didn't -- move forward. */
@@ -4052,7 +4257,6 @@
}
}
else {
- CHECKPOINT lastcp;
n = regrepeat(scan, n);
locinput = PL_reginput;
if (ln < n && PL_regkind[(U8)OP(next)] == EOL &&
@@ -4081,7 +4285,8 @@
/* If it could work, try it. */
if (c1 == -1000 || c == (UV)c1 || c == (UV)c2)
{
- TRYPAREN(paren, n, PL_reginput);
+ TRYPAREN(paren, n, PL_reginput, PLUS4);
+ /*** all unsaved local vars undefined at this
point */
REGCP_UNWIND(lastcp);
}
/* Couldn't or didn't -- back up. */
@@ -4094,29 +4299,31 @@
break;
case END:
if (PL_reg_call_cc) {
- re_cc_state *cur_call_cc = PL_reg_call_cc;
- CURCUR *cctmp = PL_regcc;
- regexp *re = PL_reg_re;
- CHECKPOINT lastcp;
- I32 tmp;
+ cur_call_cc = PL_reg_call_cc;
+ end_re = PL_reg_re;
/* Save *all* the positions. */
- const CHECKPOINT cp = regcppush(0);
+ cp = regcppush(0);
REGCP_SET(lastcp);
/* Restore parens of the caller. */
- tmp = PL_savestack_ix;
- PL_savestack_ix = PL_reg_call_cc->ss;
- regcppop();
- PL_savestack_ix = tmp;
+ {
+ I32 tmp = PL_savestack_ix;
+ PL_savestack_ix = PL_reg_call_cc->ss;
+ regcppop();
+ PL_savestack_ix = tmp;
+ }
/* Make position available to the callcc. */
PL_reginput = locinput;
cache_re(PL_reg_call_cc->re);
- PL_regcc = PL_reg_call_cc->cc;
+ oldcc = cc;
+ cc = PL_reg_call_cc->cc;
PL_reg_call_cc = PL_reg_call_cc->prev;
- if (regmatch(cur_call_cc->node)) {
+ REGMATCH(cur_call_cc->node, END);
+ /*** all unsaved local vars undefined at this point */
+ if (result) {
PL_reg_call_cc = cur_call_cc;
regcpblow(cp);
sayYES;
@@ -4124,9 +4331,9 @@
REGCP_UNWIND(lastcp);
regcppop();
PL_reg_call_cc = cur_call_cc;
- PL_regcc = cctmp;
- PL_reg_re = re;
- cache_re(re);
+ cc = oldcc;
+ PL_reg_re = end_re;
+ cache_re(end_re);
DEBUG_EXECUTE_r(
PerlIO_printf(Perl_debug_log,
@@ -4156,7 +4363,7 @@
case UNLESSM:
n = 0;
if (scan->flags) {
- s = HOPBACKc(locinput, scan->flags);
+ char *s = HOPBACKc(locinput, scan->flags);
if (!s)
goto say_yes;
PL_reginput = s;
@@ -4167,7 +4374,7 @@
case IFMATCH:
n = 1;
if (scan->flags) {
- s = HOPBACKc(locinput, scan->flags);
+ char *s = HOPBACKc(locinput, scan->flags);
if (!s)
goto say_no;
PL_reginput = s;
@@ -4176,8 +4383,9 @@
PL_reginput = locinput;
do_ifmatch:
- inner = NEXTOPER(NEXTOPER(scan));
- if (regmatch(inner) != n) {
+ REGMATCH(NEXTOPER(NEXTOPER(scan)), IFMATCH);
+ /*** all unsaved local vars undefined at this point */
+ if (result != n) {
say_no:
if (logical) {
logical = 0;
@@ -4208,8 +4416,68 @@
PTR2UV(scan), OP(scan));
Perl_croak(aTHX_ "regexp memory corruption");
}
+
reenter:
scan = next;
+ continue;
+ /* NOTREACHED */
+
+ /* simulate recursively calling regmatch(), but without actually
+ * recursing - ie save the current state on the heap rather than on
+ * the stack, then re-enter the loop. This avoids complex regexes
+ * blowing the processor stack */
+
+ start_recurse:
+ {
+ /* save existing local variables */
+ struct regmatch_state *p;
+
+ Newx(p, 1, struct regmatch_state);
+ p->prev_state = prev_state;
+ prev_state = p;
+ p->resume_state = resume_state;
+ p->scan = scan;
+ p->next = next;
+ p->minmod = minmod;
+ p->sw = sw;
+ p->logical = logical;
+ p->unwind = unwind;
+ p->cc = cc;
+ p->locinput = locinput;
+ p->n = n;
+ p->ln = ln;
+ p->c1 = c1;
+ p->c2 = c2;
+ p->paren = paren;
+ p->cp = cp;
+ p->lastcp = lastcp;
+ p->oldcc = oldcc;
+ p->lastloc = lastloc;
+ p->cache_offset = cache_offset;
+ p->cache_bit = cache_bit;
+ p->curlym_l = curlym_l;
+ p->matches = matches;
+ p->maxwanted = maxwanted;
+ p->e = e;
+ p->old = old;
+ p->count = count;
+ p->cur_call_cc = cur_call_cc;
+ p->end_re = end_re;
+ p->accept_buff = accept_buff;
+ p->accepted = accepted;
+ p->reg_call_cc = PL_reg_call_cc;
+
+ scan = new_scan;
+ locinput = PL_reginput;
+ nextchr = UCHARAT(locinput);
+ minmod = 0;
+ sw = 0;
+ logical = 0;
+ unwind = 0;
+#ifdef DEBUGGING
+ PL_regindent++;
+#endif
+ }
}
/*
@@ -4235,11 +4503,8 @@
PL_regindent--;
#endif
-#if 0 /* Breaks $^R */
- if (unwind)
- regcpblow(firstcp);
-#endif
- return 1;
+ result = 1;
+ goto exit_level;
no:
DEBUG_EXECUTE_r(
@@ -4301,7 +4566,92 @@
#ifdef DEBUGGING
PL_regindent--;
#endif
- return 0;
+ result = 0;
+exit_level:
+ if (prev_state) {
+ /* restore previous state and re-enter */
+
+ struct regmatch_state *p = prev_state;
+ resume_state = p->resume_state;
+ scan = p->scan;
+ next = p->next;
+ minmod = p->minmod;
+ sw = p->sw;
+ logical = p->logical;
+ unwind = p->unwind;
+ cc = p->cc;
+ locinput = p->locinput;
+ nextchr = UCHARAT(locinput);
+ n = p->n;
+ ln = p->ln;
+ c1 = p->c1;
+ c2 = p->c2;
+ paren = p->paren;
+ cp = p->cp;
+ lastcp = p->lastcp;
+ oldcc = p->oldcc;
+ lastloc = p->lastloc;
+ cache_offset = p->cache_offset;
+ cache_bit = p->cache_bit;
+ curlym_l = p->curlym_l;
+ matches = p->matches;
+ maxwanted = p->maxwanted;
+ e = p->e;
+ old = p->old;
+ count = p->count;
+ cur_call_cc = p->cur_call_cc;
+ end_re = p->end_re;
+ accept_buff = p->accept_buff;
+ accepted = p->accepted;
+ PL_reg_call_cc = p->reg_call_cc;
+ prev_state = p->prev_state;
+
+ switch (resume_state) {
+ case resume_TRIE1:
+ goto resume_point_TRIE1;
+ case resume_TRIE2:
+ goto resume_point_TRIE2;
+ case resume_CURLYX:
+ goto resume_point_CURLYX;
+ case resume_WHILEM1:
+ goto resume_point_WHILEM1;
+ case resume_WHILEM2:
+ goto resume_point_WHILEM2;
+ case resume_WHILEM3:
+ goto resume_point_WHILEM3;
+ case resume_WHILEM4:
+ goto resume_point_WHILEM4;
+ case resume_WHILEM5:
+ goto resume_point_WHILEM5;
+ case resume_WHILEM6:
+ goto resume_point_WHILEM6;
+ case resume_CURLYM1:
+ goto resume_point_CURLYM1;
+ case resume_CURLYM2:
+ goto resume_point_CURLYM2;
+ case resume_CURLYM3:
+ goto resume_point_CURLYM3;
+ case resume_CURLYM4:
+ goto resume_point_CURLYM4;
+ case resume_IFMATCH:
+ goto resume_point_IFMATCH;
+ case resume_PLUS1:
+ goto resume_point_PLUS1;
+ case resume_PLUS2:
+ goto resume_point_PLUS2;
+ case resume_PLUS3:
+ goto resume_point_PLUS3;
+ case resume_PLUS4:
+ goto resume_point_PLUS4;
+ case resume_END:
+ goto resume_point_END;
+ default:
+ Perl_croak(aTHX_ "regexp resume memory corruption");
+ }
+ /* NOTREACHED */
+ }
+ return result;
+
}
/*
End of Patch.
