X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/addc4ecabca79c28562dc1d9db29088f8087f3c6..7f69552c33ff9bd1eb6665f732d0f22956ac2f30:/regexec.c diff --git a/regexec.c b/regexec.c index f7f0d2b..17d0e01 100644 --- a/regexec.c +++ b/regexec.c @@ -150,6 +150,7 @@ } \ } STMT_END + static void restore_pos(pTHX_ void *arg); STATIC CHECKPOINT @@ -165,8 +166,9 @@ S_regcppush(pTHX_ I32 parenfloor) if (paren_elems_to_push < 0) Perl_croak(aTHX_ "panic: paren_elems_to_push < 0"); -#define REGCP_OTHER_ELEMS 6 +#define REGCP_OTHER_ELEMS 8 SSGROW(paren_elems_to_push + REGCP_OTHER_ELEMS); + for (p = PL_regsize; p > parenfloor; p--) { /* REGCP_PARENS_ELEMS are pushed per pairs of parentheses. */ SSPUSHINT(PL_regendp[p]); @@ -181,6 +183,8 @@ S_regcppush(pTHX_ I32 parenfloor) )); } /* REGCP_OTHER_ELEMS are pushed in any case, parentheses or no. */ + SSPUSHPTR(PL_regstartp); + SSPUSHPTR(PL_regendp); SSPUSHINT(PL_regsize); SSPUSHINT(*PL_reglastparen); SSPUSHINT(*PL_reglastcloseparen); @@ -227,7 +231,10 @@ S_regcppop(pTHX_ const regexp *rex) *PL_reglastcloseparen = SSPOPINT; *PL_reglastparen = SSPOPINT; PL_regsize = SSPOPINT; + PL_regendp=(I32 *) SSPOPPTR; + PL_regstartp=(I32 *) SSPOPPTR; + /* Now restore the parentheses context. */ for (i -= (REGCP_OTHER_ELEMS - REGCP_FRAME_ELEMS); i > 0; i -= REGCP_PAREN_ELEMS) { @@ -488,7 +495,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos, srch_end_shift -= ((strbeg - s) - srch_start_shift); srch_start_shift = strbeg - s; } - DEBUG_OPTIMISE_r({ + DEBUG_OPTIMISE_MORE_r({ PerlIO_printf(Perl_debug_log, "Check offset min: %"IVdf" Start shift: %"IVdf" End shift %"IVdf" Real End Shift: %"IVdf"\n", (IV)prog->check_offset_min, (IV)srch_start_shift, @@ -524,7 +531,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos, start_point= HOP3(s, srch_start_shift, srch_start_shift < 0 ? strbeg : strend); end_point= HOP3(strend, -srch_end_shift, strbeg); } - DEBUG_OPTIMISE_r({ + DEBUG_OPTIMISE_MORE_r({ PerlIO_printf(Perl_debug_log, "fbm_instr len=%d str=<%.*s>\n", (int)(end_point - start_point), (int)(end_point - start_point) > 20 ? 20 : (int)(end_point - start_point), @@ -719,7 +726,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos, t= (char*)HOP3( s, -prog->check_offset_max, (prog->check_offset_max<0) ? strend : strpos); - DEBUG_OPTIMISE_r( + DEBUG_OPTIMISE_MORE_r( PerlIO_printf(Perl_debug_log, "Check offset min:%"IVdf" max:%"IVdf" S:%"IVdf" t:%"IVdf" D:%"IVdf" end:%"IVdf"\n", (IV)prog->check_offset_min, @@ -1979,9 +1986,10 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char * } } if (last == NULL) { - DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, - "%sCan't trim the tail, match fails (should not happen)%s\n", - PL_colors[4], PL_colors[5])); + DEBUG_EXECUTE_r( + PerlIO_printf(Perl_debug_log, + "%sCan't trim the tail, match fails (should not happen)%s\n", + PL_colors[4], PL_colors[5])); goto phooey; /* Should not happen! */ } dontbother = strend - last + prog->float_min_offset; @@ -2021,6 +2029,8 @@ got_it: the same. */ restore_pos(aTHX_ prog); } + if (prog->paren_names) + (void)hv_iterinit(prog->paren_names); /* make sure $`, $&, $', and $digit will work later */ if ( !(flags & REXEC_NOT_FIRST) ) { @@ -2063,6 +2073,7 @@ phooey: return 0; } + /* - regtry - try match at specific point */ @@ -2084,7 +2095,7 @@ S_regtry(pTHX_ const regmatch_info *reginfo, char *startpos) PerlIO_printf(Perl_debug_log, " setting stack tmpbase at %"IVdf"\n", (IV)(PL_stack_sp - PL_stack_base)); )); - SAVEI32(cxstack[cxstack_ix].blk_oldsp); + SAVESTACK_CXPOS(); cxstack[cxstack_ix].blk_oldsp = PL_stack_sp - PL_stack_base; /* Otherwise OP_NEXTSTATE will free whatever on stack now. */ SAVETMPS; @@ -2146,16 +2157,16 @@ S_regtry(pTHX_ const regmatch_info *reginfo, char *startpos) prog->subbeg = PL_bostr; prog->sublen = PL_regeol - PL_bostr; /* strend may have been modified */ } + DEBUG_EXECUTE_r(PL_reg_starttry = startpos); prog->startp[0] = startpos - PL_bostr; PL_reginput = startpos; - PL_regstartp = prog->startp; - PL_regendp = prog->endp; PL_reglastparen = &prog->lastparen; PL_reglastcloseparen = &prog->lastcloseparen; prog->lastparen = 0; prog->lastcloseparen = 0; PL_regsize = 0; - DEBUG_EXECUTE_r(PL_reg_starttry = startpos); + PL_regstartp = prog->startp; + PL_regendp = prog->endp; if (PL_reg_start_tmpl <= prog->nparens) { PL_reg_start_tmpl = prog->nparens*3/2 + 3; if(PL_reg_start_tmp) @@ -2202,14 +2213,12 @@ S_regtry(pTHX_ const regmatch_info *reginfo, char *startpos) #define sayYES goto yes #define sayNO goto no #define sayNO_SILENT goto no_silent -#define saySAME(x) if (x) goto yes; else goto no /* we dont use STMT_START/END here because it leads to "unreachable code" warnings, which are bogus, but distracting. */ #define CACHEsayNO \ - if (st->u.whilem.cache_offset | st->u.whilem.cache_bit) \ - PL_reg_poscache[st->u.whilem.cache_offset] |= \ - (1<u.whilem.cache_bit); \ + if (ST.cache_mask) \ + PL_reg_poscache[ST.cache_offset] |= ST.cache_mask; \ sayNO /* this is used to determine how far from the left messages like @@ -2247,14 +2256,6 @@ S_push_slab(pTHX) return SLAB_FIRST(s); } -/* simulate a recursive call to regmatch */ - -#define REGMATCH(ns, where) \ - st->scan = scan; \ - scan = (ns); \ - st->resume_state = resume_##where; \ - goto start_recurse; \ - resume_point_##where: /* push a new state then goto it */ @@ -2273,109 +2274,137 @@ S_push_slab(pTHX) /* - - regmatch - main matching routine - * - * Conceptually the strategy is simple: check to see whether the current - * node matches, call self recursively to see whether the rest matches, - * and then act accordingly. In practice we make some effort to avoid - * recursion, in particular by going through "ordinary" nodes (that don't - * need to know whether the rest of the match failed) by a loop instead of - * by recursion. - */ -/* [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; +regmatch() - main matching routine + +This is basically one big switch statement in a loop. We execute an op, +set 'next' to point the next op, and continue. If we come to a point which +we may need to backtrack to on failure such as (A|B|C), we push a +backtrack state onto the backtrack stack. On failure, we pop the top +state, and re-enter the loop at the state indicated. If there are no more +states to pop, we return failure. + +Sometimes we also need to backtrack on success; for example /A+/, where +after successfully matching one A, we need to go back and try to +match another one; similarly for lookahead assertions: if the assertion +completes successfully, we backtrack to the state just before the assertion +and then carry on. In these cases, the pushed state is marked as +'backtrack on success too'. This marking is in fact done by a chain of +pointers, each pointing to the previous 'yes' state. On success, we pop to +the nearest yes state, discarding any intermediate failure-only states. +Sometimes a yes state is pushed just to force some cleanup code to be +called at the end of a successful match or submatch; e.g. (??{$re}) uses +it to free the inner regex. + +Note that failure backtracking rewinds the cursor position, while +success backtracking leaves it alone. + +A pattern is complete when the END op is executed, while a subpattern +such as (?=foo) is complete when the SUCCESS op is executed. Both of these +ops trigger the "pop to last yes state if any, otherwise return true" +behaviour. + +A common convention in this function is to use A and B to refer to the two +subpatterns (or to the first nodes thereof) in patterns like /A*B/: so A is +the subpattern to be matched possibly multiple times, while B is the entire +rest of the pattern. Variable and state names reflect this convention. + +The states in the main switch are the union of ops and failure/success of +substates associated with with that op. For example, IFMATCH is the op +that does lookahead assertions /(?=A)B/ and so the IFMATCH state means +'execute IFMATCH'; while IFMATCH_A is a state saying that we have just +successfully matched A and IFMATCH_A_fail is a state saying that we have +just failed to match A. Resume states always come in pairs. The backtrack +state we push is marked as 'IFMATCH_A', but when that is popped, we resume +at IFMATCH_A or IFMATCH_A_fail, depending on whether we are backtracking +on success or failure. + +The struct that holds a backtracking state is actually a big union, with +one variant for each major type of op. The variable st points to the +top-most backtrack struct. To make the code clearer, within each +block of code we #define ST to alias the relevant union. + +Here's a concrete example of a (vastly oversimplified) IFMATCH +implementation: + + switch (state) { + .... + +#define ST st->u.ifmatch + + case IFMATCH: // we are executing the IFMATCH op, (?=A)B + ST.foo = ...; // some state we wish to save ... - while (scan != NULL) { - a++; // do stuff with a and b - ... - switch (OP(scan)) { - case FOO: { - int local = 3; - ... - if (regmatch(...)) // recurse - goto yes; - } - ... - } - } - yes: - return 1; - } + // push a yes backtrack state with a resume value of + // IFMATCH_A/IFMATCH_A_fail, then continue execution at the + // first node of A: + PUSH_YES_STATE_GOTO(IFMATCH_A, A); + // NOTREACHED + + case IFMATCH_A: // we have successfully executed A; now continue with B + next = B; + bar = ST.foo; // do something with the preserved value + break; + + case IFMATCH_A_fail: // A failed, so the assertion failed + ...; // do some housekeeping, then ... + sayNO; // propagate the failure + +#undef ST - * Now it looks something like this: + ... + } - typedef struct { - int a, b, local; - int resume_state; - } regmatch_state; +For any old-timers reading this who are familiar with the old recursive +approach, the code above is equivalent to: - S_regmatch() { - regmatch_state *st = new(); - int depth=0; - st->a++; // do stuff with a and b + case IFMATCH: // we are executing the IFMATCH op, (?=A)B + { + int foo = ... ... - while (scan != NULL) { - ... - switch (OP(scan)) { - case FOO: { - st->local = 3; - ... - st->scan = scan; - scan = ...; - st->resume_state = resume_FOO; - goto start_recurse; // recurse - - resume_point_FOO: - if (result) - goto yes; - } - ... - } - start_recurse: - st = new(); push a new state - st->a = 1; st->b = 2; - depth++; - } - yes: - result = 1; - if (depth--) { - st = pop(); - switch (resume_state) { - case resume_FOO: - goto resume_point_FOO; - ... - } + if (regmatch(A)) { + next = B; + bar = foo; + break; } - return result + ...; // do some housekeeping, then ... + sayNO; // propagate the failure } - - * 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 . - * - * States (ie the st pointer) are allocated in slabs of about 4K in size. - * PL_regmatch_state always points to the currently active state, and - * PL_regmatch_slab points to the slab currently containing PL_regmatch_state. - * The first time regmatch is called, the first slab is allocated, and is - * never freed until interpreter desctruction. When the slab is full, - * a new one is allocated chained to the end. At exit from regmatch, slabs - * allocated since entry are freed. - */ + +The topmost backtrack state, pointed to by st, is usually free. If you +want to claim it, populate any ST.foo fields in it with values you wish to +save, then do one of + + PUSH_STATE_GOTO(resume_state, node); + PUSH_YES_STATE_GOTO(resume_state, node); + +which sets that backtrack state's resume value to 'resume_state', pushes a +new free entry to the top of the backtrack stack, then goes to 'node'. +On backtracking, the free slot is popped, and the saved state becomes the +new free state. An ST.foo field in this new top state can be temporarily +accessed to retrieve values, but once the main loop is re-entered, it +becomes available for reuse. + +Note that the depth of the backtrack stack constantly increases during the +left-to-right execution of the pattern, rather than going up and down with +the pattern nesting. For example the stack is at its maximum at Z at the +end of the pattern, rather than at X in the following: + + /(((X)+)+)+....(Y)+....Z/ + +The only exceptions to this are lookahead/behind assertions and the cut, +(?>A), which pop all the backtrack states associated with A before +continuing. + +Bascktrack state structs are allocated in slabs of about 4K in size. +PL_regmatch_state and st always point to the currently active state, +and PL_regmatch_slab points to the slab currently containing +PL_regmatch_state. The first time regmatch() is called, the first slab is +allocated, and is never freed until interpreter destruction. When the slab +is full, a new one is allocated and chained to the end. At exit from +regmatch(), slabs allocated since entry are freed. + +*/ #define DEBUG_STATE_pp(pp) \ @@ -2480,6 +2509,30 @@ S_dump_exec_pos(pTHX_ const char *locinput, #endif +/* reg_check_named_buff_matched() + * Checks to see if a named buffer has matched. The data array of + * buffer numbers corresponding to the buffer is expected to reside + * in the regexp->data->data array in the slot stored in the ARG() of + * node involved. Note that this routine doesn't actually care about the + * name, that information is not preserved from compilation to execution. + * Returns the index of the leftmost defined buffer with the given name + * or 0 if non of the buffers matched. + */ +STATIC I32 +S_reg_check_named_buff_matched(pTHX_ const regexp *rex, const regnode *scan) { + I32 n; + SV *sv_dat=(SV*)rex->data->data[ ARG( scan ) ]; + I32 *nums=(I32*)SvPVX(sv_dat); + for ( n=0; n= nums[n] && + PL_regendp[nums[n]] != -1) + { + return nums[n]; + } + } + return 0; +} + STATIC I32 /* 0 failure, 1 success */ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) { @@ -2501,20 +2554,34 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* cache heavy used fields of st in registers */ register regnode *scan; register regnode *next; - register I32 n = 0; /* initialize to shut up compiler warning */ + register I32 n = 0; /* general value; init to avoid compiler warning */ + register I32 ln = 0; /* len or last; init to avoid compiler warning */ register char *locinput = PL_reginput; - - /* these variables are NOT saved during a recusive RFEGMATCH: */ register I32 nextchr; /* is always set to UCHARAT(locinput) */ + bool result = 0; /* return value of S_regmatch */ - int depth = 0; /* depth of recursion */ + int depth = 0; /* depth of backtrack stack */ + int nochange_depth = 0; /* depth of RECURSE recursion with nochange*/ regmatch_state *yes_state = NULL; /* state to pop to on success of subpattern */ regmatch_state *cur_eval = NULL; /* most recent EVAL_AB state */ struct regmatch_state *cur_curlyx = NULL; /* most recent curlyx */ U32 state_num; - - I32 parenfloor = 0; + + /* these three flags are set by various ops to signal information to + * the very next op. They have a useful lifetime of exactly one loop + * iteration, and are not preserved or restored by state pushes/pops + */ + bool sw = 0; /* the condition value in (?(cond)a|b) */ + bool minmod = 0; /* the next "{n,m}" is a "{n,m}?" */ + int logical = 0; /* the following EVAL is: + 0: (?{...}) + 1: (?(?{...})X|Y) + 2: (??{...}) + or the following IFMATCH/UNLESSM is: + false: plain (?=foo) + true: used as a condition: (?(?=foo)) + */ #ifdef DEBUGGING GET_RE_DEBUG_FLAGS_DECL; @@ -2538,11 +2605,6 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) if (st > SLAB_LAST(PL_regmatch_slab)) st = PL_regmatch_state = S_push_slab(aTHX); - st->minmod = 0; - st->sw = 0; - st->logical = 0; - cur_curlyx = NULL; - /* Note that nextchr is a byte even in UTF */ nextchr = UCHARAT(locinput); scan = prog; @@ -2702,13 +2764,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) ST.accepted = 0; /* how many accepting states we have seen */ ST.B = next; ST.jump = trie->jump; - -#ifdef DEBUGGING ST.me = scan; -#endif - - /* traverse the TRIE keeping track of all accepting states we transition through until we get to a failing node. @@ -2833,10 +2890,10 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) locinput = PL_reginput; nextchr = UCHARAT(locinput); - if ( !ST.jump ) + if ( !ST.jump || !ST.jump[ST.accept_buff[0].wordnum]) scan = ST.B; else - scan = ST.B - ST.jump[ST.accept_buff[0].wordnum]; + scan = ST.me + ST.jump[ST.accept_buff[0].wordnum]; continue; /* execute rest of RE */ } @@ -2882,9 +2939,9 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) SV ** const tmp = RX_DEBUG(reginfo->prog) ? av_fetch( trie->words, ST.accept_buff[ best ].wordnum - 1, 0 ) : NULL; - regnode *nextop=!ST.jump ? + regnode *nextop=(!ST.jump || !ST.jump[ST.accept_buff[best].wordnum]) ? ST.B : - ST.B - ST.jump[ST.accept_buff[best].wordnum]; + ST.me + ST.jump[ST.accept_buff[best].wordnum]; PerlIO_printf( Perl_debug_log, "%*s %strying alternation #%d <%s> at node #%d %s\n", REPORT_CODE_OFF+depth*2, "", PL_colors[4], @@ -2901,11 +2958,11 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) best = ST.accepted; } PL_reginput = (char *)ST.accept_buff[ best ].endpos; - if ( !ST.jump ) { + if ( !ST.jump || !ST.jump[ST.accept_buff[best].wordnum]) { PUSH_STATE_GOTO(TRIE_next, ST.B); /* NOTREACHED */ } else { - PUSH_STATE_GOTO(TRIE_next, ST.B - ST.jump[ST.accept_buff[best].wordnum]); + PUSH_STATE_GOTO(TRIE_next, ST.me + ST.jump[ST.accept_buff[best].wordnum]); /* NOTREACHED */ } /* NOTREACHED */ @@ -2916,11 +2973,11 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) case EXACT: { char *s = STRING(scan); - st->ln = STR_LEN(scan); + ln = STR_LEN(scan); if (do_utf8 != UTF) { /* The target and the pattern have differing utf8ness. */ char *l = locinput; - const char * const e = s + st->ln; + const char * const e = s + ln; if (do_utf8) { /* The target is utf8, the pattern is not utf8. */ @@ -2958,11 +3015,11 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* Inline the first character, for speed. */ if (UCHARAT(s) != nextchr) sayNO; - if (PL_regeol - locinput < st->ln) + if (PL_regeol - locinput < ln) sayNO; - if (st->ln > 1 && memNE(s, locinput, st->ln)) + if (ln > 1 && memNE(s, locinput, ln)) sayNO; - locinput += st->ln; + locinput += ln; nextchr = UCHARAT(locinput); break; } @@ -2971,14 +3028,14 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* FALL THROUGH */ case EXACTF: { char * const s = STRING(scan); - st->ln = STR_LEN(scan); + ln = STR_LEN(scan); if (do_utf8 || UTF) { /* Either target or the pattern are utf8. */ const char * const l = locinput; char *e = PL_regeol; - if (ibcmp_utf8(s, 0, st->ln, (bool)UTF, + if (ibcmp_utf8(s, 0, ln, (bool)UTF, l, &e, 0, do_utf8)) { /* One more case for the sharp s: * pack("U0U*", 0xDF) =~ /ss/i, @@ -2986,7 +3043,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) * byte sequence for the U+00DF. */ if (!(do_utf8 && toLOWER(s[0]) == 's' && - st->ln >= 2 && + ln >= 2 && toLOWER(s[1]) == 's' && (U8)l[0] == 0xC3 && e - l >= 2 && @@ -3005,13 +3062,13 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) UCHARAT(s) != ((OP(scan) == EXACTF) ? PL_fold : PL_fold_locale)[nextchr]) sayNO; - if (PL_regeol - locinput < st->ln) + if (PL_regeol - locinput < ln) sayNO; - if (st->ln > 1 && (OP(scan) == EXACTF - ? ibcmp(s, locinput, st->ln) - : ibcmp_locale(s, locinput, st->ln))) + if (ln > 1 && (OP(scan) == EXACTF + ? ibcmp(s, locinput, ln) + : ibcmp_locale(s, locinput, ln))) sayNO; - locinput += st->ln; + locinput += ln; nextchr = UCHARAT(locinput); break; } @@ -3103,35 +3160,35 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* was last char in word? */ if (do_utf8) { if (locinput == PL_bostr) - st->ln = '\n'; + ln = '\n'; else { const U8 * const r = reghop3((U8*)locinput, -1, (U8*)PL_bostr); - st->ln = utf8n_to_uvchr(r, UTF8SKIP(r), 0, uniflags); + ln = utf8n_to_uvchr(r, UTF8SKIP(r), 0, uniflags); } if (OP(scan) == BOUND || OP(scan) == NBOUND) { - st->ln = isALNUM_uni(st->ln); + ln = isALNUM_uni(ln); LOAD_UTF8_CHARCLASS_ALNUM(); n = swash_fetch(PL_utf8_alnum, (U8*)locinput, do_utf8); } else { - st->ln = isALNUM_LC_uvchr(UNI_TO_NATIVE(st->ln)); + ln = isALNUM_LC_uvchr(UNI_TO_NATIVE(ln)); n = isALNUM_LC_utf8((U8*)locinput); } } else { - st->ln = (locinput != PL_bostr) ? + ln = (locinput != PL_bostr) ? UCHARAT(locinput - 1) : '\n'; if (OP(scan) == BOUND || OP(scan) == NBOUND) { - st->ln = isALNUM(st->ln); + ln = isALNUM(ln); n = isALNUM(nextchr); } else { - st->ln = isALNUM_LC(st->ln); + ln = isALNUM_LC(ln); n = isALNUM_LC(nextchr); } } - if (((!st->ln) == (!n)) == (OP(scan) == BOUND || + if (((!ln) == (!n)) == (OP(scan) == BOUND || OP(scan) == BOUNDL)) sayNO; break; @@ -3253,22 +3310,42 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) locinput++; nextchr = UCHARAT(locinput); break; + + case NREFFL: + { + char *s; + char type; + PL_reg_flags |= RF_tainted; + /* FALL THROUGH */ + case NREF: + case NREFF: + type = OP(scan); + n = reg_check_named_buff_matched(rex,scan); + + if ( n ) { + type = REF + ( type - NREF ); + goto do_ref; + } else { + sayNO; + } + /* unreached */ case REFFL: PL_reg_flags |= RF_tainted; /* FALL THROUGH */ case REF: - case REFF: { - char *s; + case REFF: n = ARG(scan); /* which paren pair */ - st->ln = PL_regstartp[n]; + type = OP(scan); + do_ref: + ln = PL_regstartp[n]; PL_reg_leftiter = PL_reg_maxiter; /* Void cache */ - if ((I32)*PL_reglastparen < n || st->ln == -1) + if ((I32)*PL_reglastparen < n || ln == -1) sayNO; /* Do not match unless seen CLOSEn. */ - if (st->ln == PL_regendp[n]) + if (ln == PL_regendp[n]) break; - s = PL_bostr + st->ln; - if (do_utf8 && OP(scan) != REF) { /* REF can do byte comparison */ + s = PL_bostr + ln; + if (do_utf8 && type != REF) { /* REF can do byte comparison */ char *l = locinput; const char *e = PL_bostr + PL_regendp[n]; /* @@ -3276,7 +3353,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) * in the 8-bit case (no pun intended) because in Unicode we * have to map both upper and title case to lower case. */ - if (OP(scan) == REFF) { + if (type == REFF) { while (s < e) { STRLEN ulen1, ulen2; U8 tmpbuf1[UTF8_MAXBYTES_CASE+1]; @@ -3299,24 +3376,23 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* Inline the first character, for speed. */ if (UCHARAT(s) != nextchr && - (OP(scan) == REF || - (UCHARAT(s) != ((OP(scan) == REFF - ? PL_fold : PL_fold_locale)[nextchr])))) + (type == REF || + (UCHARAT(s) != (type == REFF + ? PL_fold : PL_fold_locale)[nextchr]))) sayNO; - st->ln = PL_regendp[n] - st->ln; - if (locinput + st->ln > PL_regeol) + ln = PL_regendp[n] - ln; + if (locinput + ln > PL_regeol) sayNO; - if (st->ln > 1 && (OP(scan) == REF - ? memNE(s, locinput, st->ln) - : (OP(scan) == REFF - ? ibcmp(s, locinput, st->ln) - : ibcmp_locale(s, locinput, st->ln)))) + if (ln > 1 && (type == REF + ? memNE(s, locinput, ln) + : (type == REFF + ? ibcmp(s, locinput, ln) + : ibcmp_locale(s, locinput, ln)))) sayNO; - locinput += st->ln; + locinput += ln; nextchr = UCHARAT(locinput); break; - } - + } case NOTHING: case TAIL: break; @@ -3325,10 +3401,39 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) #undef ST #define ST st->u.eval - - case EVAL: /* /(?{A})B/ /(??{A})B/ and /(?(?{A})X|Y)B/ */ { SV *ret; + regexp *re; + regnode *startpoint; + + case SRECURSE: + case RECURSE: /* /(...(?1))/ */ + if (cur_eval && cur_eval->locinput==locinput) { + if (cur_eval->u.eval.close_paren == ARG(scan)) + Perl_croak(aTHX_ "Infinite recursion in RECURSE in regexp"); + if ( ++nochange_depth > MAX_RECURSE_EVAL_NOCHANGE_DEPTH ) + Perl_croak(aTHX_ "RECURSE without pos change exceeded limit in regexp"); + } else { + nochange_depth = 0; + } + re = rex; + (void)ReREFCNT_inc(rex); + if (OP(scan)==RECURSE) { + startpoint = scan + ARG2L(scan); + ST.close_paren = ARG(scan); + } else { + startpoint = re->program+1; + ST.close_paren = 0; + } + goto eval_recurse_doit; + /* NOTREACHED */ + case EVAL: /* /(?{A})B/ /(??{A})B/ and /(?(?{A})X|Y)B/ */ + if (cur_eval && cur_eval->locinput==locinput) { + if ( ++nochange_depth > MAX_RECURSE_EVAL_NOCHANGE_DEPTH ) + Perl_croak(aTHX_ "EVAL without pos change exceeded limit in regexp"); + } else { + nochange_depth = 0; + } { /* execute the code in the {...} */ dSP; @@ -3355,14 +3460,14 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) PL_op = oop; PAD_RESTORE_LOCAL(old_comppad); PL_curcop = ocurcop; - if (!st->logical) { + if (!logical) { /* /(?{...})/ */ sv_setsv(save_scalar(PL_replgv), ret); break; } } - if (st->logical == 2) { /* Postponed subexpression: /(??{...})/ */ - regexp *re; + if (logical == 2) { /* Postponed subexpression: /(??{...})/ */ + logical = 0; { /* extract RE object from returned value; compiling if * necessary */ @@ -3399,18 +3504,37 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) PL_regsize = osize; } } + DEBUG_EXECUTE_r( + debug_start_match(re, do_utf8, locinput, PL_regeol, + "Matching embedded"); + ); + startpoint = re->program + 1; + ST.close_paren = 0; /* only used for RECURSE */ + /* borrowed from regtry */ + if (PL_reg_start_tmpl <= re->nparens) { + PL_reg_start_tmpl = re->nparens*3/2 + 3; + if(PL_reg_start_tmp) + Renew(PL_reg_start_tmp, PL_reg_start_tmpl, char*); + else + Newx(PL_reg_start_tmp, PL_reg_start_tmpl, char*); + } + eval_recurse_doit: /* Share code with RECURSE below this line */ /* run the pattern returned from (??{...}) */ ST.cp = regcppush(0); /* Save *all* the positions. */ REGCP_SET(ST.lastcp); + + PL_regstartp = re->startp; /* essentially NOOP on RECURSE */ + PL_regendp = re->endp; /* essentially NOOP on RECURSE */ + *PL_reglastparen = 0; *PL_reglastcloseparen = 0; PL_reginput = locinput; + PL_regsize = 0; /* XXXX This is too dramatic a measure... */ PL_reg_maxiter = 0; - st->logical = 0; ST.toggle_reg_flags = PL_reg_flags; if (re->reganch & ROPT_UTF8) PL_reg_flags |= RF_utf8; @@ -3425,18 +3549,13 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) ST.B = next; ST.prev_eval = cur_eval; cur_eval = st; - - DEBUG_EXECUTE_r( - debug_start_match(re, do_utf8, locinput, PL_regeol, - "Matching embedded"); - ); /* now continue from first node in postoned RE */ - PUSH_YES_STATE_GOTO(EVAL_AB, re->program + 1); + PUSH_YES_STATE_GOTO(EVAL_AB, startpoint); /* NOTREACHED */ } - /* /(?(?{...})X|Y)/ */ - st->sw = (bool)SvTRUE(ret); - st->logical = 0; + /* logical is 1, /(?(?{...})X|Y)/ */ + sw = (bool)SvTRUE(ret); + logical = 0; break; } @@ -3466,7 +3585,6 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* XXXX This is too dramatic a measure... */ PL_reg_maxiter = 0; sayNO_SILENT; - #undef ST case OPEN: @@ -3479,17 +3597,33 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) n = ARG(scan); /* which paren pair */ PL_regstartp[n] = PL_reg_start_tmp[n] - PL_bostr; PL_regendp[n] = locinput - PL_bostr; + /*if (n > PL_regsize) + PL_regsize = n;*/ if (n > (I32)*PL_reglastparen) *PL_reglastparen = n; *PL_reglastcloseparen = n; + if (cur_eval && cur_eval->u.eval.close_paren == (U32)n) { + goto fake_end; + } break; case GROUPP: n = ARG(scan); /* which paren pair */ - st->sw = (bool)((I32)*PL_reglastparen >= n && PL_regendp[n] != -1); + sw = (bool)((I32)*PL_reglastparen >= n && PL_regendp[n] != -1); break; + case NGROUPP: + /* reg_check_named_buff_matched returns 0 for no match */ + sw = (bool)(0 < reg_check_named_buff_matched(rex,scan)); + break; + case RECURSEP: + n = ARG(scan); + sw = (cur_eval && (!n || cur_eval->u.eval.close_paren == n)); + break; + case DEFINEP: + sw = 0; + break; case IFTHEN: PL_reg_leftiter = PL_reg_maxiter; /* Void cache */ - if (st->sw) + if (sw) next = NEXTOPER(NEXTOPER(scan)); else { next = scan + ARG(scan); @@ -3498,212 +3632,198 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) } break; case LOGICAL: - st->logical = scan->flags; + logical = scan->flags; break; + /******************************************************************* - cur_curlyx points to the regmatch_state associated with the most recent CURLYX. - This struct contains info about the innermost (...)* loop (an - "infoblock"), and a pointer to the next outer cur_curlyx. - Here is how Y(A)*Z is processed (if it is compiled into CURLYX/WHILEM): +The CURLYX/WHILEM pair of ops handle the most generic case of the /A*B/ +pattern, where A and B are subpatterns. (For simple A, CURLYM or +STAR/PLUS/CURLY/CURLYN are used instead.) + +A*B is compiled as - 1) After matching Y, regnode for CURLYX is processed; +On entry to the subpattern, CURLYX is called. This pushes a CURLYX +state, which contains the current count, initialised to -1. It also sets +cur_curlyx to point to this state, with any previous value saved in the +state block. - 2) This regnode populates cur_curlyx, and calls regmatch() recursively - with the starting point at WHILEM node; +CURLYX then jumps straight to the WHILEM op, rather than executing A, +since the pattern may possibly match zero times (i.e. it's a while {} loop +rather than a do {} while loop). - 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 - greediness). The information about where are nodes for "A" - and "Z" is read from cur_curlyx, as is info on how many times "A" - was already matched, and greediness. +Each entry to WHILEM represents a successful match of A. The count in the +CURLYX block is incremented, another WHILEM state is pushed, and execution +passes to A or B depending on greediness and the current count. - 4) After A matches, the same WHILEM node is hit again. +For example, if matching against the string a1a2a3b (where the aN are +substrings that match /A/), then the match progresses as follows: (the +pushed states are interspersed with the bits of strings matched so far): - 5) Each time WHILEM is hit, cur_curlyx is the infoblock created by CURLYX - of the same pair. Thus when WHILEM tries to match Z, it temporarily - resets cur_curlyx, 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. + + + a1 + a1 a2 + a1 a2 a3 + a1 a2 a3 b - Currently present infoblocks form a tree with a stem formed by cur_curlyx - and whatever it mentions via ->next, and additional attached trees - corresponding to temporarily unset infoblocks as in "5" above. +(Contrast this with something like CURLYM, which maintains only a single +backtrack state: - 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. + a1 + a1 a2 + a1 a2 a3 + a1 a2 a3 b +) - In fact in the picture below we do not show failed matches for Z and T - by WHILEM blocks. [We illustrate minimal matches, since for them it is - more obvious *why* one needs to *temporary* unset infoblocks.] +Each WHILEM state block marks a point to backtrack to upon partial failure +of A or B, and also contains some minor state data related to that +iteration. The CURLYX block, pointed to by cur_curlyx, contains the +overall state, such as the count, and pointers to the A and B ops. - Matched REx position InfoBlocks Comment - (Y(A)*?Z)*?T x - Y(A)*?Z)*?T x <- O - Y (A)*?Z)*?T x <- O - Y A)*?Z)*?T x <- O <- I - YA )*?Z)*?T x <- O <- I - YA A)*?Z)*?T x <- O <- I - YAA )*?Z)*?T x <- O <- I - YAA Z)*?T x <- O # Temporary unset I - I +This is complicated slightly by nested CURLYX/WHILEM's. Since cur_curlyx +must always point to the *current* CURLYX block, the rules are: - YAAZ Y(A)*?Z)*?T x <- O - I +When executing CURLYX, save the old cur_curlyx in the CURLYX state block, +and set cur_curlyx to point the new block. - YAAZY (A)*?Z)*?T x <- O - I +When popping the CURLYX block after a successful or unsuccessful match, +restore the previous cur_curlyx. - YAAZY A)*?Z)*?T x <- O <- I - I +When WHILEM is about to execute B, save the current cur_curlyx, and set it +to the outer one saved in the CURLYX block. - YAAZYA )*?Z)*?T x <- O <- I - I +When popping the WHILEM block after a successful or unsuccessful B match, +restore the previous cur_curlyx. - YAAZYA Z)*?T x <- O # Temporary unset I - I,I +Here's an example for the pattern (AI* BI)*BO +I and O refer to inner and outer, C and W refer to CURLYX and WHILEM: - YAAZYAZ )*?T x <- O - I,I +cur_ +curlyx backtrack stack +------ --------------- +NULL +CO +CI ai +CO ai bi +NULL ai bi bo - YAAZYAZ T x # Temporary unset O - O - I,I +At this point the pattern succeeds, and we work back down the stack to +clean up, restoring as we go: - YAAZYAZT x - O - I,I - *******************************************************************/ +CO ai bi +CI ai +CO +NULL - case CURLYX: { - /* No need to save/restore up to this paren */ - parenfloor = scan->flags; - - /* Dave says: - - CURLYX and WHILEM are always paired: they're the moral - equivalent of pp_enteriter anbd pp_iter. - - The only time next could be null is if the node tree is - corrupt. This was mentioned on p5p a few days ago. - - See http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2006-04/msg00556.html - So we'll assert that this is true: - */ - assert(next); - if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */ - next += ARG(next); - /* XXXX Probably it is better to teach regpush to support - parenfloor > PL_regsize... */ - if (parenfloor > (I32)*PL_reglastparen) - parenfloor = *PL_reglastparen; /* Pessimization... */ - - st->u.curlyx.cp = PL_savestack_ix; - st->u.curlyx.outercc = cur_curlyx; - cur_curlyx = st; - /* these fields contain the state of the current curly. - * they are accessed by subsequent WHILEMs; - * cur and lastloc are also updated by WHILEM */ - st->u.curlyx.parenfloor = parenfloor; - st->u.curlyx.cur = -1; /* this will be updated by WHILEM */ - st->u.curlyx.min = ARG1(scan); - st->u.curlyx.max = ARG2(scan); - st->u.curlyx.scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS; - st->u.curlyx.lastloc = 0; - /* st->next and st->minmod are also read by WHILEM */ +*******************************************************************/ - PL_reginput = locinput; - REGMATCH(PREVOPER(next), CURLYX); /* start on the WHILEM */ - /*** all unsaved local vars undefined at this point */ - regcpblow(st->u.curlyx.cp); - cur_curlyx = st->u.curlyx.outercc; - saySAME(result); - } +#define ST st->u.curlyx + + case CURLYX: /* start of /A*B/ (for complex A) */ + { + /* No need to save/restore up to this paren */ + I32 parenfloor = scan->flags; + + assert(next); /* keep Coverity happy */ + if (OP(PREVOPER(next)) == NOTHING) /* LONGJMP */ + next += ARG(next); + + /* XXXX Probably it is better to teach regpush to support + parenfloor > PL_regsize... */ + if (parenfloor > (I32)*PL_reglastparen) + parenfloor = *PL_reglastparen; /* Pessimization... */ + + ST.prev_curlyx= cur_curlyx; + cur_curlyx = st; + ST.cp = PL_savestack_ix; + + /* these fields contain the state of the current curly. + * they are accessed by subsequent WHILEMs */ + ST.parenfloor = parenfloor; + ST.min = ARG1(scan); + ST.max = ARG2(scan); + ST.A = NEXTOPER(scan) + EXTRA_STEP_2ARGS; + ST.B = next; + ST.minmod = minmod; + minmod = 0; + ST.count = -1; /* this will be updated by WHILEM */ + ST.lastloc = NULL; /* this will be updated by WHILEM */ + + PL_reginput = locinput; + PUSH_YES_STATE_GOTO(CURLYX_end, PREVOPER(next)); /* NOTREACHED */ - case WHILEM: { - /* - * This is really hard to understand, because after we match - * what we're trying to match, we must make sure the rest of - * the REx is going to match for sure, and to do that we have - * to go back UP the parse tree by recursing ever deeper. And - * if it fails, we have to reset our parent's current state - * that we can try again after backing off. - */ + } - /* Dave says: - - cur_curlyx gets initialised by CURLYX ready for use by WHILEM. - So again, unless somethings been corrupted, cur_curlyx cannot - be null at that point in WHILEM. - - See http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2006-04/msg00556.html - So we'll assert that this is true: - */ - assert(cur_curlyx); - st->u.whilem.lastloc = cur_curlyx->u.curlyx.lastloc; /* Detection of 0-len. */ - st->u.whilem.cache_offset = 0; - st->u.whilem.cache_bit = 0; - - n = cur_curlyx->u.curlyx.cur + 1; /* how many we know we matched */ - PL_reginput = locinput; + case CURLYX_end: /* just finished matching all of A*B */ + regcpblow(ST.cp); + cur_curlyx = ST.prev_curlyx; + sayYES; + /* NOTREACHED */ - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%*s %ld out of %ld..%ld cc=%"UVxf"\n", - REPORT_CODE_OFF+depth*2, "", - (long)n, (long)cur_curlyx->u.curlyx.min, - (long)cur_curlyx->u.curlyx.max, - PTR2UV(cur_curlyx)) - ); + case CURLYX_end_fail: /* just failed to match all of A*B */ + regcpblow(ST.cp); + cur_curlyx = ST.prev_curlyx; + sayNO; + /* NOTREACHED */ - /* If degenerate scan matches "", assume scan done. */ - if (locinput == cur_curlyx->u.curlyx.lastloc && n >= - cur_curlyx->u.curlyx.min) - { - st->u.whilem.savecc = cur_curlyx; - cur_curlyx = cur_curlyx->u.curlyx.outercc; - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%*s empty match detected, try continuation...\n", - REPORT_CODE_OFF+depth*2, "") - ); - REGMATCH(st->u.whilem.savecc->next, WHILEM1); - /*** all unsaved local vars undefined at this point */ - cur_curlyx = st->u.whilem.savecc; - if (result) - sayYES; - sayNO; - } +#undef ST +#define ST st->u.whilem - /* First just match a string of min scans. */ - - if (n < cur_curlyx->u.curlyx.min) { - cur_curlyx->u.curlyx.cur = n; - cur_curlyx->u.curlyx.lastloc = locinput; - REGMATCH(cur_curlyx->u.curlyx.scan, WHILEM2); - /*** all unsaved local vars undefined at this point */ - if (result) - sayYES; - cur_curlyx->u.curlyx.cur = n - 1; - cur_curlyx->u.curlyx.lastloc = st->u.whilem.lastloc; - sayNO; - } + case WHILEM: /* just matched an A in /A*B/ (for complex A) */ + { + /* see the discussion above about CURLYX/WHILEM */ + I32 n; + assert(cur_curlyx); /* keep Coverity happy */ + n = ++cur_curlyx->u.curlyx.count; /* how many A's matched */ + ST.save_lastloc = cur_curlyx->u.curlyx.lastloc; + ST.cache_offset = 0; + ST.cache_mask = 0; + + PL_reginput = locinput; + + DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, + "%*s whilem: matched %ld out of %ld..%ld\n", + REPORT_CODE_OFF+depth*2, "", (long)n, + (long)cur_curlyx->u.curlyx.min, + (long)cur_curlyx->u.curlyx.max) + ); + + /* First just match a string of min A's. */ + + if (n < cur_curlyx->u.curlyx.min) { + cur_curlyx->u.curlyx.lastloc = locinput; + PUSH_STATE_GOTO(WHILEM_A_pre, cur_curlyx->u.curlyx.A); + /* NOTREACHED */ + } + + /* If degenerate A matches "", assume A done. */ + + if (locinput == cur_curlyx->u.curlyx.lastloc) { + DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, + "%*s whilem: empty match detected, trying continuation...\n", + REPORT_CODE_OFF+depth*2, "") + ); + goto do_whilem_B_max; + } + + /* super-linear cache processing */ + + if (scan->flags) { - if (scan->flags) { - /* Check whether we already were at this position. - Postpone detection until we know the match is not - *that* much linear. */ if (!PL_reg_maxiter) { + /* start the countdown: Postpone detection until we + * know the match is not *that* much linear. */ PL_reg_maxiter = (PL_regeol - PL_bostr + 1) * (scan->flags>>4); /* possible overflow for long strings and many CURLYX's */ if (PL_reg_maxiter < 0) PL_reg_maxiter = I32_MAX; PL_reg_leftiter = PL_reg_maxiter; } + if (PL_reg_leftiter-- == 0) { + /* initialise cache */ const I32 size = (PL_reg_maxiter + 7)/8; if (PL_reg_poscache) { if ((I32)PL_reg_poscache_size < size) { @@ -3716,124 +3836,133 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) PL_reg_poscache_size = size; Newxz(PL_reg_poscache, size, char); } - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%sDetected a super-linear match, switching on caching%s...\n", - PL_colors[4], PL_colors[5]) - ); + DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, + "%swhilem: Detected a super-linear match, switching on caching%s...\n", + PL_colors[4], PL_colors[5]) + ); } + if (PL_reg_leftiter < 0) { - st->u.whilem.cache_offset = locinput - PL_bostr; - - 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; - if (PL_reg_poscache[st->u.whilem.cache_offset] & (1<u.whilem.cache_bit)) { - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%*s already tried at this position...\n", - REPORT_CODE_OFF+depth*2, "") + /* have we already failed at this position? */ + I32 offset, mask; + offset = (scan->flags & 0xf) - 1 + + (locinput - PL_bostr) * (scan->flags>>4); + mask = 1 << (offset % 8); + offset /= 8; + if (PL_reg_poscache[offset] & mask) { + DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log, + "%*s whilem: (cache) already tried at this position...\n", + REPORT_CODE_OFF+depth*2, "") ); sayNO; /* cache records failure */ } + ST.cache_offset = offset; + ST.cache_mask = mask; } - } + } - /* Prefer next over scan for minimal matching. */ - - if (cur_curlyx->minmod) { - st->u.whilem.savecc = cur_curlyx; - cur_curlyx = cur_curlyx->u.curlyx.outercc; - st->u.whilem.cp = regcppush(st->u.whilem.savecc->u.curlyx.parenfloor); - REGCP_SET(st->u.whilem.lastcp); - REGMATCH(st->u.whilem.savecc->next, WHILEM3); - /*** all unsaved local vars undefined at this point */ - cur_curlyx = st->u.whilem.savecc; - if (result) { - regcpblow(st->u.whilem.cp); - sayYES; /* All done. */ - } - REGCP_UNWIND(st->u.whilem.lastcp); - regcppop(rex); - - if (n >= cur_curlyx->u.curlyx.max) { /* Maximum greed exceeded? */ - if (ckWARN(WARN_REGEXP) && n >= REG_INFTY - && !(PL_reg_flags & RF_warned)) { - PL_reg_flags |= RF_warned; - Perl_warner(aTHX_ packWARN(WARN_REGEXP), "%s limit (%d) exceeded", - "Complex regular subexpression recursion", - REG_INFTY - 1); - } - CACHEsayNO; - } + /* Prefer B over A for minimal matching. */ - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%*s trying longer...\n", - REPORT_CODE_OFF+depth*2, "") - ); - /* Try scanning more and see if it helps. */ - PL_reginput = locinput; - cur_curlyx->u.curlyx.cur = n; - cur_curlyx->u.curlyx.lastloc = locinput; - st->u.whilem.cp = regcppush(cur_curlyx->u.curlyx.parenfloor); - REGCP_SET(st->u.whilem.lastcp); - REGMATCH(cur_curlyx->u.curlyx.scan, WHILEM4); - /*** all unsaved local vars undefined at this point */ - if (result) { - regcpblow(st->u.whilem.cp); - sayYES; - } - REGCP_UNWIND(st->u.whilem.lastcp); - regcppop(rex); - cur_curlyx->u.curlyx.cur = n - 1; - cur_curlyx->u.curlyx.lastloc = st->u.whilem.lastloc; - CACHEsayNO; - } + if (cur_curlyx->u.curlyx.minmod) { + ST.save_curlyx = cur_curlyx; + cur_curlyx = cur_curlyx->u.curlyx.prev_curlyx; + ST.cp = regcppush(ST.save_curlyx->u.curlyx.parenfloor); + REGCP_SET(ST.lastcp); + PUSH_YES_STATE_GOTO(WHILEM_B_min, ST.save_curlyx->u.curlyx.B); + /* NOTREACHED */ + } - /* Prefer scan over next for maximal matching. */ - - if (n < cur_curlyx->u.curlyx.max) { /* More greed allowed? */ - st->u.whilem.cp = regcppush(cur_curlyx->u.curlyx.parenfloor); - cur_curlyx->u.curlyx.cur = n; - cur_curlyx->u.curlyx.lastloc = locinput; - REGCP_SET(st->u.whilem.lastcp); - REGMATCH(cur_curlyx->u.curlyx.scan, WHILEM5); - /*** all unsaved local vars undefined at this point */ - if (result) { - regcpblow(st->u.whilem.cp); - sayYES; - } - REGCP_UNWIND(st->u.whilem.lastcp); - regcppop(rex); /* Restore some previous $s? */ - PL_reginput = locinput; - DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, - "%*s failed, try continuation...\n", - REPORT_CODE_OFF+depth*2, "") - ); - } - if (ckWARN(WARN_REGEXP) && n >= REG_INFTY - && !(PL_reg_flags & RF_warned)) { + /* Prefer A over B for maximal matching. */ + + if (n < cur_curlyx->u.curlyx.max) { /* More greed allowed? */ + ST.cp = regcppush(cur_curlyx->u.curlyx.parenfloor); + cur_curlyx->u.curlyx.lastloc = locinput; + REGCP_SET(ST.lastcp); + PUSH_STATE_GOTO(WHILEM_A_max, cur_curlyx->u.curlyx.A); + /* NOTREACHED */ + } + goto do_whilem_B_max; + } + /* NOTREACHED */ + + case WHILEM_B_min: /* just matched B in a minimal match */ + case WHILEM_B_max: /* just matched B in a maximal match */ + cur_curlyx = ST.save_curlyx; + sayYES; + /* NOTREACHED */ + + case WHILEM_B_max_fail: /* just failed to match B in a maximal match */ + cur_curlyx = ST.save_curlyx; + cur_curlyx->u.curlyx.lastloc = ST.save_lastloc; + cur_curlyx->u.curlyx.count--; + CACHEsayNO; + /* NOTREACHED */ + + case WHILEM_A_min_fail: /* just failed to match A in a minimal match */ + REGCP_UNWIND(ST.lastcp); + regcppop(rex); + /* FALL THROUGH */ + case WHILEM_A_pre_fail: /* just failed to match even minimal A */ + cur_curlyx->u.curlyx.lastloc = ST.save_lastloc; + cur_curlyx->u.curlyx.count--; + CACHEsayNO; + /* NOTREACHED */ + + case WHILEM_A_max_fail: /* just failed to match A in a maximal match */ + REGCP_UNWIND(ST.lastcp); + regcppop(rex); /* Restore some previous $s? */ + PL_reginput = locinput; + DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, + "%*s whilem: failed, trying continuation...\n", + REPORT_CODE_OFF+depth*2, "") + ); + do_whilem_B_max: + if (cur_curlyx->u.curlyx.count >= REG_INFTY + && ckWARN(WARN_REGEXP) + && !(PL_reg_flags & RF_warned)) + { + PL_reg_flags |= RF_warned; + Perl_warner(aTHX_ packWARN(WARN_REGEXP), "%s limit (%d) exceeded", + "Complex regular subexpression recursion", + REG_INFTY - 1); + } + + /* now try B */ + ST.save_curlyx = cur_curlyx; + cur_curlyx = cur_curlyx->u.curlyx.prev_curlyx; + PUSH_YES_STATE_GOTO(WHILEM_B_max, ST.save_curlyx->u.curlyx.B); + /* NOTREACHED */ + + case WHILEM_B_min_fail: /* just failed to match B in a minimal match */ + cur_curlyx = ST.save_curlyx; + REGCP_UNWIND(ST.lastcp); + regcppop(rex); + + if (cur_curlyx->u.curlyx.count >= cur_curlyx->u.curlyx.max) { + /* Maximum greed exceeded */ + if (cur_curlyx->u.curlyx.count >= REG_INFTY + && ckWARN(WARN_REGEXP) + && !(PL_reg_flags & RF_warned)) + { PL_reg_flags |= RF_warned; - Perl_warner(aTHX_ packWARN(WARN_REGEXP), "%s limit (%d) exceeded", - "Complex regular subexpression recursion", - REG_INFTY - 1); + Perl_warner(aTHX_ packWARN(WARN_REGEXP), + "%s limit (%d) exceeded", + "Complex regular subexpression recursion", + REG_INFTY - 1); } - - /* Failed deeper matches of scan, so see if this one works. */ - st->u.whilem.savecc = cur_curlyx; - cur_curlyx = cur_curlyx->u.curlyx.outercc; - REGMATCH(st->u.whilem.savecc->next, WHILEM6); - /*** all unsaved local vars undefined at this point */ - cur_curlyx = st->u.whilem.savecc; - if (result) - sayYES; - cur_curlyx->u.curlyx.cur = n - 1; - cur_curlyx->u.curlyx.lastloc = st->u.whilem.lastloc; + cur_curlyx->u.curlyx.count--; CACHEsayNO; } + + DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, + "%*s trying longer...\n", REPORT_CODE_OFF+depth*2, "") + ); + /* Try grabbing another A and see if it helps. */ + PL_reginput = locinput; + cur_curlyx->u.curlyx.lastloc = locinput; + ST.cp = regcppush(cur_curlyx->u.curlyx.parenfloor); + REGCP_SET(ST.lastcp); + PUSH_STATE_GOTO(WHILEM_A_min, ST.save_curlyx->u.curlyx.A); /* NOTREACHED */ #undef ST @@ -3865,6 +3994,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) for (n = *PL_reglastparen; n > ST.lastparen; n--) PL_regendp[n] = -1; *PL_reglastparen = n; + /*dmq: *PL_reglastcloseparen = n; */ scan = ST.next_branch; /* no more branches? */ if (!scan || (OP(scan) != BRANCH && OP(scan) != BRANCHJ)) @@ -3873,7 +4003,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* NOTREACHED */ case MINMOD: - st->minmod = 1; + minmod = 1; break; #undef ST @@ -3903,8 +4033,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) ST.B = next; ST.alen = 0; ST.count = 0; - ST.minmod = st->minmod; - st->minmod = 0; + ST.minmod = minmod; + minmod = 0; ST.c1 = CHRTEST_UNINIT; REGCP_SET(ST.cp); @@ -3944,13 +4074,21 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) ); locinput = PL_reginput; - if (ST.count < (ST.minmod ? ARG1(ST.me) : ARG2(ST.me))) + + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.me->flags) + goto fake_end; + + if ( ST.count < (ST.minmod ? ARG1(ST.me) : ARG2(ST.me)) ) goto curlym_do_A; /* try to match another A */ goto curlym_do_B; /* try to match B */ case CURLYM_A_fail: /* just failed to match an A */ REGCP_UNWIND(ST.cp); - if (ST.minmod || ST.count < ARG1(ST.me) /* min*/ ) + + if (ST.minmod || ST.count < ARG1(ST.me) /* min*/ + || (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.me->flags)) sayNO; curlym_do_B: /* execute the B in /A{m,n}B/ */ @@ -3999,10 +4137,20 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) PL_regstartp[paren] = HOPc(PL_reginput, -ST.alen) - PL_bostr; PL_regendp[paren] = PL_reginput - PL_bostr; + /*dmq: *PL_reglastcloseparen = paren; */ } else PL_regendp[paren] = -1; + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.me->flags) + { + if (ST.count) + goto fake_end; + else + sayNO; + } } + PUSH_STATE_GOTO(CURLYM_B, ST.B); /* match B */ /* NOTREACHED */ @@ -4028,6 +4176,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) if (success) { \ PL_regstartp[paren] = HOPc(locinput, -1) - PL_bostr; \ PL_regendp[paren] = locinput - PL_bostr; \ + *PL_reglastcloseparen = paren; \ } \ else \ PL_regendp[paren] = -1; \ @@ -4053,6 +4202,11 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) *PL_reglastparen = ST.paren; ST.min = ARG1(scan); /* min to match */ ST.max = ARG2(scan); /* max to match */ + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.paren) { + ST.min=1; + ST.max=1; + } scan = regnext(NEXTOPER(scan) + NODE_STEP_REGNODE); goto repeat; case CURLY: /* /A{m,n}B/ where A is width 1 */ @@ -4132,8 +4286,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) ST.A = scan; ST.B = next; PL_reginput = locinput; - if (st->minmod) { - st->minmod = 0; + if (minmod) { + minmod = 0; if (ST.min && regrepeat(rex, ST.A, ST.min) < ST.min) sayNO; ST.count = ST.min; @@ -4258,6 +4412,10 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) } PL_reginput = locinput; CURLY_SETPAREN(ST.paren, ST.count); + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.paren) { + goto fake_end; + } PUSH_STATE_GOTO(CURLY_B_min_known, ST.B); } /* NOTREACHED */ @@ -4279,6 +4437,10 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) { curly_try_B_min: CURLY_SETPAREN(ST.paren, ST.count); + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.paren) { + goto fake_end; + } PUSH_STATE_GOTO(CURLY_B_min, ST.B); } } @@ -4297,6 +4459,10 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* If it could work, try it. */ if (ST.c1 == CHRTEST_VOID || c == (UV)ST.c1 || c == (UV)ST.c2) { CURLY_SETPAREN(ST.paren, ST.count); + if (cur_eval && cur_eval->u.eval.close_paren && + cur_eval->u.eval.close_paren == ST.paren) { + goto fake_end; + } PUSH_STATE_GOTO(CURLY_B_max, ST.B); /* NOTREACHED */ } @@ -4316,8 +4482,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) #undef ST - case END: + fake_end: if (cur_eval) { /* we've just finished A in /(??{A})B/; now continue with B */ I32 tmpix; @@ -4345,8 +4511,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) st->u.eval.prev_eval = cur_eval; cur_eval = cur_eval->u.eval.prev_eval; DEBUG_EXECUTE_r( - PerlIO_printf(Perl_debug_log, "%*s EVAL trying tail ...\n", - REPORT_CODE_OFF+depth*2, "");); + PerlIO_printf(Perl_debug_log, "%*s EVAL trying tail ... %x\n", + REPORT_CODE_OFF+depth*2, "",(int)cur_eval);); PUSH_YES_STATE_GOTO(EVAL_AB, st->u.eval.prev_eval->u.eval.B); /* match B */ } @@ -4390,9 +4556,9 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) char * const s = HOPBACKc(locinput, scan->flags); if (!s) { /* trivial fail */ - if (st->logical) { - st->logical = 0; - st->sw = 1 - (bool)ST.wanted; + if (logical) { + logical = 0; + sw = 1 - (bool)ST.wanted; } else if (ST.wanted) sayNO; @@ -4408,6 +4574,7 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) do_ifmatch: ST.me = scan; + ST.logical = logical; /* execute body of (?...A) */ PUSH_YES_STATE_GOTO(IFMATCH_A, NEXTOPER(NEXTOPER(scan))); /* NOTREACHED */ @@ -4417,9 +4584,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) /* FALL THROUGH */ case IFMATCH_A: /* body of (?...A) succeeded */ - if (st->logical) { - st->logical = 0; - st->sw = (bool)ST.wanted; + if (ST.logical) { + sw = (bool)ST.wanted; } else if (!ST.wanted) sayNO; @@ -4442,6 +4608,8 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) if (next == scan) next = NULL; break; + case OPFAIL: + sayNO; default: PerlIO_printf(Perl_error_log, "%"UVxf" %d\n", PTR2UV(scan), OP(scan)); @@ -4469,11 +4637,6 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) if (newst > SLAB_LAST(PL_regmatch_slab)) newst = S_push_slab(aTHX); PL_regmatch_state = newst; - /* XXX probably don't need to initialise these */ - newst->minmod = 0; - newst->sw = 0; - newst->logical = 0; - locinput = PL_reginput; nextchr = UCHARAT(locinput); @@ -4481,39 +4644,6 @@ S_regmatch(pTHX_ const regmatch_info *reginfo, regnode *prog) 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: - { - /* push new state */ - regmatch_state *oldst = st; - - DEBUG_STATE_pp("push"); - depth++; - st->u.yes.prev_yes_state = yes_state; - yes_state = st; - - /* grab the next free state slot */ - st++; - if (st > SLAB_LAST(PL_regmatch_slab)) - st = S_push_slab(aTHX); - PL_regmatch_state = st; - - oldst->next = next; - oldst->n = n; - oldst->locinput = locinput; - - locinput = PL_reginput; - nextchr = UCHARAT(locinput); - st->minmod = 0; - st->sw = 0; - st->logical = 0; - - } } /* @@ -4554,52 +4684,8 @@ yes: yes_state = st->u.yes.prev_yes_state; PL_regmatch_state = st; - switch (st->resume_state) { - case resume_CURLYX: - case resume_WHILEM1: - case resume_WHILEM2: - case resume_WHILEM3: - case resume_WHILEM4: - case resume_WHILEM5: - case resume_WHILEM6: - result = 1; - /* restore previous state and re-enter */ - scan = st->scan; - next = st->next; - n = st->n; - locinput= st->locinput; - nextchr = UCHARAT(locinput); - switch (st->resume_state) { - 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; - } - Perl_croak(aTHX_ "unexpected whilem resume state"); - - case EVAL_AB: - case IFMATCH_A: - case CURLYM_A: - state_num = st->resume_state; - goto reenter_switch; - - case CURLYM_B: - case BRANCH_next: - case TRIE_next: - case CURLY_B_max: - default: - Perl_croak(aTHX_ "unexpected yes resume state"); - } + state_num = st->resume_state; + goto reenter_switch; } DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch successful!%s\n", @@ -4617,8 +4703,6 @@ no: ); no_silent: - result = 0; - if (depth) { /* there's a previous state to backtrack to */ st--; @@ -4627,9 +4711,6 @@ no_silent: st = SLAB_LAST(PL_regmatch_slab); } PL_regmatch_state = st; - scan = st->scan; - next = st->next; - n = st->n; locinput= st->locinput; nextchr = UCHARAT(locinput); @@ -4638,38 +4719,10 @@ no_silent: if (yes_state == st) yes_state = st->u.yes.prev_yes_state; - switch (st->resume_state) { - 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 TRIE_next: - case EVAL_AB: - case BRANCH_next: - case CURLYM_A: - case CURLYM_B: - case IFMATCH_A: - case CURLY_B_max: - case CURLY_B_min: - case CURLY_B_min_known: - state_num = st->resume_state + 1; /* failure = success + 1 */ - goto reenter_switch; - - default: - Perl_croak(aTHX_ "regexp resume memory corruption"); - } + state_num = st->resume_state + 1; /* failure = success + 1 */ + goto reenter_switch; } + result = 0; final_exit: