| 1 | #ifdef PERL_EXT_RE_BUILD |
| 2 | #include "re_top.h" |
| 3 | #endif |
| 4 | |
| 5 | #include "EXTERN.h" |
| 6 | #define PERL_IN_REGEX_ENGINE |
| 7 | #define PERL_IN_REGCOMP_ANY |
| 8 | #define PERL_IN_REGCOMP_STUDY_C |
| 9 | #include "perl.h" |
| 10 | |
| 11 | #ifdef PERL_IN_XSUB_RE |
| 12 | # include "re_comp.h" |
| 13 | #else |
| 14 | # include "regcomp.h" |
| 15 | #endif |
| 16 | |
| 17 | #include "invlist_inline.h" |
| 18 | #include "unicode_constants.h" |
| 19 | #include "regcomp_internal.h" |
| 20 | |
| 21 | #define INIT_AND_WITHP \ |
| 22 | assert(!and_withp); \ |
| 23 | Newx(and_withp, 1, regnode_ssc); \ |
| 24 | SAVEFREEPV(and_withp) |
| 25 | |
| 26 | |
| 27 | STATIC void |
| 28 | S_unwind_scan_frames(pTHX_ const void *p) |
| 29 | { |
| 30 | PERL_ARGS_ASSERT_UNWIND_SCAN_FRAMES; |
| 31 | scan_frame *f= (scan_frame *)p; |
| 32 | do { |
| 33 | scan_frame *n= f->next_frame; |
| 34 | Safefree(f); |
| 35 | f= n; |
| 36 | } while (f); |
| 37 | } |
| 38 | |
| 39 | /* Follow the next-chain of the current node and optimize away |
| 40 | all the NOTHINGs from it. |
| 41 | */ |
| 42 | STATIC void |
| 43 | S_rck_elide_nothing(pTHX_ regnode *node) |
| 44 | { |
| 45 | PERL_ARGS_ASSERT_RCK_ELIDE_NOTHING; |
| 46 | |
| 47 | if (OP(node) != CURLYX) { |
| 48 | const int max = (REGNODE_OFF_BY_ARG(OP(node)) |
| 49 | ? I32_MAX |
| 50 | /* I32 may be smaller than U16 on CRAYs! */ |
| 51 | : (I32_MAX < U16_MAX ? I32_MAX : U16_MAX)); |
| 52 | int off = (REGNODE_OFF_BY_ARG(OP(node)) ? ARG(node) : NEXT_OFF(node)); |
| 53 | int noff; |
| 54 | regnode *n = node; |
| 55 | |
| 56 | /* Skip NOTHING and LONGJMP. */ |
| 57 | while ( |
| 58 | (n = regnext(n)) |
| 59 | && ( |
| 60 | (REGNODE_TYPE(OP(n)) == NOTHING && (noff = NEXT_OFF(n))) |
| 61 | || ((OP(n) == LONGJMP) && (noff = ARG(n))) |
| 62 | ) |
| 63 | && off + noff < max |
| 64 | ) { |
| 65 | off += noff; |
| 66 | } |
| 67 | if (REGNODE_OFF_BY_ARG(OP(node))) |
| 68 | ARG(node) = off; |
| 69 | else |
| 70 | NEXT_OFF(node) = off; |
| 71 | } |
| 72 | return; |
| 73 | } |
| 74 | |
| 75 | |
| 76 | /* |
| 77 | * As best we can, determine the characters that can match the start of |
| 78 | * the given EXACTF-ish node. This is for use in creating ssc nodes, so there |
| 79 | * can be false positive matches |
| 80 | * |
| 81 | * Returns the invlist as a new SV*; it is the caller's responsibility to |
| 82 | * call SvREFCNT_dec() when done with it. |
| 83 | */ |
| 84 | STATIC SV* |
| 85 | S_make_exactf_invlist(pTHX_ RExC_state_t *pRExC_state, regnode *node) |
| 86 | { |
| 87 | const U8 * s = (U8*)STRING(node); |
| 88 | SSize_t bytelen = STR_LEN(node); |
| 89 | UV uc; |
| 90 | /* Start out big enough for 2 separate code points */ |
| 91 | SV* invlist = _new_invlist(4); |
| 92 | |
| 93 | PERL_ARGS_ASSERT_MAKE_EXACTF_INVLIST; |
| 94 | |
| 95 | if (! UTF) { |
| 96 | uc = *s; |
| 97 | |
| 98 | /* We punt and assume can match anything if the node begins |
| 99 | * with a multi-character fold. Things are complicated. For |
| 100 | * example, /ffi/i could match any of: |
| 101 | * "\N{LATIN SMALL LIGATURE FFI}" |
| 102 | * "\N{LATIN SMALL LIGATURE FF}I" |
| 103 | * "F\N{LATIN SMALL LIGATURE FI}" |
| 104 | * plus several other things; and making sure we have all the |
| 105 | * possibilities is hard. */ |
| 106 | if (is_MULTI_CHAR_FOLD_latin1_safe(s, s + bytelen)) { |
| 107 | invlist = _add_range_to_invlist(invlist, 0, UV_MAX); |
| 108 | } |
| 109 | else { |
| 110 | /* Any Latin1 range character can potentially match any |
| 111 | * other depending on the locale, and in Turkic locales, 'I' and |
| 112 | * 'i' can match U+130 and U+131 */ |
| 113 | if (OP(node) == EXACTFL) { |
| 114 | _invlist_union(invlist, PL_Latin1, &invlist); |
| 115 | if (isALPHA_FOLD_EQ(uc, 'I')) { |
| 116 | invlist = add_cp_to_invlist(invlist, |
| 117 | LATIN_SMALL_LETTER_DOTLESS_I); |
| 118 | invlist = add_cp_to_invlist(invlist, |
| 119 | LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE); |
| 120 | } |
| 121 | } |
| 122 | else { |
| 123 | /* But otherwise, it matches at least itself. We can |
| 124 | * quickly tell if it has a distinct fold, and if so, |
| 125 | * it matches that as well */ |
| 126 | invlist = add_cp_to_invlist(invlist, uc); |
| 127 | if (IS_IN_SOME_FOLD_L1(uc)) |
| 128 | invlist = add_cp_to_invlist(invlist, PL_fold_latin1[uc]); |
| 129 | } |
| 130 | |
| 131 | /* Some characters match above-Latin1 ones under /i. This |
| 132 | * is true of EXACTFL ones when the locale is UTF-8 */ |
| 133 | if (HAS_NONLATIN1_SIMPLE_FOLD_CLOSURE(uc) |
| 134 | && (! isASCII(uc) || ! inRANGE(OP(node), EXACTFAA, |
| 135 | EXACTFAA_NO_TRIE))) |
| 136 | { |
| 137 | add_above_Latin1_folds(pRExC_state, (U8) uc, &invlist); |
| 138 | } |
| 139 | } |
| 140 | } |
| 141 | else { /* Pattern is UTF-8 */ |
| 142 | U8 folded[UTF8_MAX_FOLD_CHAR_EXPAND * UTF8_MAXBYTES_CASE + 1] = { '\0' }; |
| 143 | const U8* e = s + bytelen; |
| 144 | IV fc; |
| 145 | |
| 146 | fc = uc = utf8_to_uvchr_buf(s, s + bytelen, NULL); |
| 147 | |
| 148 | /* The only code points that aren't folded in a UTF EXACTFish |
| 149 | * node are the problematic ones in EXACTFL nodes */ |
| 150 | if (OP(node) == EXACTFL && is_PROBLEMATIC_LOCALE_FOLDEDS_START_cp(uc)) { |
| 151 | /* We need to check for the possibility that this EXACTFL |
| 152 | * node begins with a multi-char fold. Therefore we fold |
| 153 | * the first few characters of it so that we can make that |
| 154 | * check */ |
| 155 | U8 *d = folded; |
| 156 | int i; |
| 157 | |
| 158 | fc = -1; |
| 159 | for (i = 0; i < UTF8_MAX_FOLD_CHAR_EXPAND && s < e; i++) { |
| 160 | if (isASCII(*s)) { |
| 161 | *(d++) = (U8) toFOLD(*s); |
| 162 | if (fc < 0) { /* Save the first fold */ |
| 163 | fc = *(d-1); |
| 164 | } |
| 165 | s++; |
| 166 | } |
| 167 | else { |
| 168 | STRLEN len; |
| 169 | UV fold = toFOLD_utf8_safe(s, e, d, &len); |
| 170 | if (fc < 0) { /* Save the first fold */ |
| 171 | fc = fold; |
| 172 | } |
| 173 | d += len; |
| 174 | s += UTF8SKIP(s); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | /* And set up so the code below that looks in this folded |
| 179 | * buffer instead of the node's string */ |
| 180 | e = d; |
| 181 | s = folded; |
| 182 | } |
| 183 | |
| 184 | /* When we reach here 's' points to the fold of the first |
| 185 | * character(s) of the node; and 'e' points to far enough along |
| 186 | * the folded string to be just past any possible multi-char |
| 187 | * fold. |
| 188 | * |
| 189 | * Like the non-UTF case above, we punt if the node begins with a |
| 190 | * multi-char fold */ |
| 191 | |
| 192 | if (is_MULTI_CHAR_FOLD_utf8_safe(s, e)) { |
| 193 | invlist = _add_range_to_invlist(invlist, 0, UV_MAX); |
| 194 | } |
| 195 | else { /* Single char fold */ |
| 196 | unsigned int k; |
| 197 | U32 first_fold; |
| 198 | const U32 * remaining_folds; |
| 199 | Size_t folds_count; |
| 200 | |
| 201 | /* It matches itself */ |
| 202 | invlist = add_cp_to_invlist(invlist, fc); |
| 203 | |
| 204 | /* ... plus all the things that fold to it, which are found in |
| 205 | * PL_utf8_foldclosures */ |
| 206 | folds_count = _inverse_folds(fc, &first_fold, |
| 207 | &remaining_folds); |
| 208 | for (k = 0; k < folds_count; k++) { |
| 209 | UV c = (k == 0) ? first_fold : remaining_folds[k-1]; |
| 210 | |
| 211 | /* /aa doesn't allow folds between ASCII and non- */ |
| 212 | if ( inRANGE(OP(node), EXACTFAA, EXACTFAA_NO_TRIE) |
| 213 | && isASCII(c) != isASCII(fc)) |
| 214 | { |
| 215 | continue; |
| 216 | } |
| 217 | |
| 218 | invlist = add_cp_to_invlist(invlist, c); |
| 219 | } |
| 220 | |
| 221 | if (OP(node) == EXACTFL) { |
| 222 | |
| 223 | /* If either [iI] are present in an EXACTFL node the above code |
| 224 | * should have added its normal case pair, but under a Turkish |
| 225 | * locale they could match instead the case pairs from it. Add |
| 226 | * those as potential matches as well */ |
| 227 | if (isALPHA_FOLD_EQ(fc, 'I')) { |
| 228 | invlist = add_cp_to_invlist(invlist, |
| 229 | LATIN_SMALL_LETTER_DOTLESS_I); |
| 230 | invlist = add_cp_to_invlist(invlist, |
| 231 | LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE); |
| 232 | } |
| 233 | else if (fc == LATIN_SMALL_LETTER_DOTLESS_I) { |
| 234 | invlist = add_cp_to_invlist(invlist, 'I'); |
| 235 | } |
| 236 | else if (fc == LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE) { |
| 237 | invlist = add_cp_to_invlist(invlist, 'i'); |
| 238 | } |
| 239 | } |
| 240 | } |
| 241 | } |
| 242 | |
| 243 | return invlist; |
| 244 | } |
| 245 | |
| 246 | |
| 247 | /* Mark that we cannot extend a found fixed substring at this point. |
| 248 | Update the longest found anchored substring or the longest found |
| 249 | floating substrings if needed. */ |
| 250 | |
| 251 | void |
| 252 | Perl_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, |
| 253 | SSize_t *minlenp, int is_inf) |
| 254 | { |
| 255 | const STRLEN l = CHR_SVLEN(data->last_found); |
| 256 | SV * const longest_sv = data->substrs[data->cur_is_floating].str; |
| 257 | const STRLEN old_l = CHR_SVLEN(longest_sv); |
| 258 | DECLARE_AND_GET_RE_DEBUG_FLAGS; |
| 259 | |
| 260 | PERL_ARGS_ASSERT_SCAN_COMMIT; |
| 261 | |
| 262 | if ((l >= old_l) && ((l > old_l) || (data->flags & SF_BEFORE_EOL))) { |
| 263 | const U8 i = data->cur_is_floating; |
| 264 | SvSetMagicSV(longest_sv, data->last_found); |
| 265 | data->substrs[i].min_offset = l ? data->last_start_min : data->pos_min; |
| 266 | |
| 267 | if (!i) /* fixed */ |
| 268 | data->substrs[0].max_offset = data->substrs[0].min_offset; |
| 269 | else { /* float */ |
| 270 | data->substrs[1].max_offset = |
| 271 | (is_inf) |
| 272 | ? OPTIMIZE_INFTY |
| 273 | : (l |
| 274 | ? data->last_start_max |
| 275 | : (data->pos_delta > OPTIMIZE_INFTY - data->pos_min |
| 276 | ? OPTIMIZE_INFTY |
| 277 | : data->pos_min + data->pos_delta)); |
| 278 | } |
| 279 | |
| 280 | data->substrs[i].flags &= ~SF_BEFORE_EOL; |
| 281 | data->substrs[i].flags |= data->flags & SF_BEFORE_EOL; |
| 282 | data->substrs[i].minlenp = minlenp; |
| 283 | data->substrs[i].lookbehind = 0; |
| 284 | } |
| 285 | |
| 286 | SvCUR_set(data->last_found, 0); |
| 287 | { |
| 288 | SV * const sv = data->last_found; |
| 289 | if (SvUTF8(sv) && SvMAGICAL(sv)) { |
| 290 | MAGIC * const mg = mg_find(sv, PERL_MAGIC_utf8); |
| 291 | if (mg) |
| 292 | mg->mg_len = 0; |
| 293 | } |
| 294 | } |
| 295 | data->last_end = -1; |
| 296 | data->flags &= ~SF_BEFORE_EOL; |
| 297 | DEBUG_STUDYDATA("commit", data, 0, is_inf, -1, -1, -1); |
| 298 | } |
| 299 | |
| 300 | /* An SSC is just a regnode_charclass_posix with an extra field: the inversion |
| 301 | * list that describes which code points it matches */ |
| 302 | |
| 303 | STATIC void |
| 304 | S_ssc_anything(pTHX_ regnode_ssc *ssc) |
| 305 | { |
| 306 | /* Set the SSC 'ssc' to match an empty string or any code point */ |
| 307 | |
| 308 | PERL_ARGS_ASSERT_SSC_ANYTHING; |
| 309 | |
| 310 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 311 | |
| 312 | /* mortalize so won't leak */ |
| 313 | ssc->invlist = sv_2mortal(_add_range_to_invlist(NULL, 0, UV_MAX)); |
| 314 | ANYOF_FLAGS(ssc) |= SSC_MATCHES_EMPTY_STRING; /* Plus matches empty */ |
| 315 | } |
| 316 | |
| 317 | STATIC int |
| 318 | S_ssc_is_anything(const regnode_ssc *ssc) |
| 319 | { |
| 320 | /* Returns TRUE if the SSC 'ssc' can match the empty string and any code |
| 321 | * point; FALSE otherwise. Thus, this is used to see if using 'ssc' buys |
| 322 | * us anything: if the function returns TRUE, 'ssc' hasn't been restricted |
| 323 | * in any way, so there's no point in using it */ |
| 324 | |
| 325 | UV start = 0, end = 0; /* Initialize due to messages from dumb compiler */ |
| 326 | bool ret; |
| 327 | |
| 328 | PERL_ARGS_ASSERT_SSC_IS_ANYTHING; |
| 329 | |
| 330 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 331 | |
| 332 | if (! (ANYOF_FLAGS(ssc) & SSC_MATCHES_EMPTY_STRING)) { |
| 333 | return FALSE; |
| 334 | } |
| 335 | |
| 336 | /* See if the list consists solely of the range 0 - Infinity */ |
| 337 | invlist_iterinit(ssc->invlist); |
| 338 | ret = invlist_iternext(ssc->invlist, &start, &end) |
| 339 | && start == 0 |
| 340 | && end == UV_MAX; |
| 341 | |
| 342 | invlist_iterfinish(ssc->invlist); |
| 343 | |
| 344 | if (ret) { |
| 345 | return TRUE; |
| 346 | } |
| 347 | |
| 348 | /* If e.g., both \w and \W are set, matches everything */ |
| 349 | if (ANYOF_POSIXL_SSC_TEST_ANY_SET(ssc)) { |
| 350 | int i; |
| 351 | for (i = 0; i < ANYOF_POSIXL_MAX; i += 2) { |
| 352 | if (ANYOF_POSIXL_TEST(ssc, i) && ANYOF_POSIXL_TEST(ssc, i+1)) { |
| 353 | return TRUE; |
| 354 | } |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | return FALSE; |
| 359 | } |
| 360 | |
| 361 | void |
| 362 | Perl_ssc_init(pTHX_ const RExC_state_t *pRExC_state, regnode_ssc *ssc) |
| 363 | { |
| 364 | /* Initializes the SSC 'ssc'. This includes setting it to match an empty |
| 365 | * string, any code point, or any posix class under locale */ |
| 366 | |
| 367 | PERL_ARGS_ASSERT_SSC_INIT; |
| 368 | |
| 369 | Zero(ssc, 1, regnode_ssc); |
| 370 | set_ANYOF_SYNTHETIC(ssc); |
| 371 | ARG_SET(ssc, ANYOF_MATCHES_ALL_OUTSIDE_BITMAP_VALUE); |
| 372 | ssc_anything(ssc); |
| 373 | |
| 374 | /* If any portion of the regex is to operate under locale rules that aren't |
| 375 | * fully known at compile time, initialization includes it. The reason |
| 376 | * this isn't done for all regexes is that the optimizer was written under |
| 377 | * the assumption that locale was all-or-nothing. Given the complexity and |
| 378 | * lack of documentation in the optimizer, and that there are inadequate |
| 379 | * test cases for locale, many parts of it may not work properly, it is |
| 380 | * safest to avoid locale unless necessary. */ |
| 381 | if (RExC_contains_locale) { |
| 382 | ANYOF_POSIXL_SETALL(ssc); |
| 383 | } |
| 384 | else { |
| 385 | ANYOF_POSIXL_ZERO(ssc); |
| 386 | } |
| 387 | } |
| 388 | |
| 389 | STATIC int |
| 390 | S_ssc_is_cp_posixl_init(const RExC_state_t *pRExC_state, |
| 391 | const regnode_ssc *ssc) |
| 392 | { |
| 393 | /* Returns TRUE if the SSC 'ssc' is in its initial state with regard only |
| 394 | * to the list of code points matched, and locale posix classes; hence does |
| 395 | * not check its flags) */ |
| 396 | |
| 397 | UV start = 0, end = 0; /* Initialize due to messages from dumb compiler */ |
| 398 | bool ret; |
| 399 | |
| 400 | PERL_ARGS_ASSERT_SSC_IS_CP_POSIXL_INIT; |
| 401 | |
| 402 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 403 | |
| 404 | invlist_iterinit(ssc->invlist); |
| 405 | ret = invlist_iternext(ssc->invlist, &start, &end) |
| 406 | && start == 0 |
| 407 | && end == UV_MAX; |
| 408 | |
| 409 | invlist_iterfinish(ssc->invlist); |
| 410 | |
| 411 | if (! ret) { |
| 412 | return FALSE; |
| 413 | } |
| 414 | |
| 415 | if (RExC_contains_locale && ! ANYOF_POSIXL_SSC_TEST_ALL_SET(ssc)) { |
| 416 | return FALSE; |
| 417 | } |
| 418 | |
| 419 | return TRUE; |
| 420 | } |
| 421 | |
| 422 | |
| 423 | STATIC SV* |
| 424 | S_get_ANYOF_cp_list_for_ssc(pTHX_ const RExC_state_t *pRExC_state, |
| 425 | const regnode_charclass* const node) |
| 426 | { |
| 427 | /* Returns a mortal inversion list defining which code points are matched |
| 428 | * by 'node', which is of ANYOF-ish type . Handles complementing the |
| 429 | * result if appropriate. If some code points aren't knowable at this |
| 430 | * time, the returned list must, and will, contain every code point that is |
| 431 | * a possibility. */ |
| 432 | |
| 433 | SV* invlist = NULL; |
| 434 | SV* only_utf8_locale_invlist = NULL; |
| 435 | bool new_node_has_latin1 = FALSE; |
| 436 | const U8 flags = (REGNODE_TYPE(OP(node)) == ANYOF) |
| 437 | ? ANYOF_FLAGS(node) |
| 438 | : 0; |
| 439 | |
| 440 | PERL_ARGS_ASSERT_GET_ANYOF_CP_LIST_FOR_SSC; |
| 441 | |
| 442 | /* Look at the data structure created by S_set_ANYOF_arg() */ |
| 443 | if (ANYOF_MATCHES_ALL_OUTSIDE_BITMAP(node)) { |
| 444 | invlist = sv_2mortal(_new_invlist(1)); |
| 445 | invlist = _add_range_to_invlist(invlist, NUM_ANYOF_CODE_POINTS, UV_MAX); |
| 446 | } |
| 447 | else if (ANYOF_HAS_AUX(node)) { |
| 448 | const U32 n = ARG(node); |
| 449 | SV * const rv = MUTABLE_SV(RExC_rxi->data->data[n]); |
| 450 | AV * const av = MUTABLE_AV(SvRV(rv)); |
| 451 | SV **const ary = AvARRAY(av); |
| 452 | |
| 453 | if (av_tindex_skip_len_mg(av) >= DEFERRED_USER_DEFINED_INDEX) { |
| 454 | |
| 455 | /* Here there are things that won't be known until runtime -- we |
| 456 | * have to assume it could be anything */ |
| 457 | invlist = sv_2mortal(_new_invlist(1)); |
| 458 | return _add_range_to_invlist(invlist, 0, UV_MAX); |
| 459 | } |
| 460 | else if (ary[INVLIST_INDEX]) { |
| 461 | |
| 462 | /* Use the node's inversion list */ |
| 463 | invlist = sv_2mortal(invlist_clone(ary[INVLIST_INDEX], NULL)); |
| 464 | } |
| 465 | |
| 466 | /* Get the code points valid only under UTF-8 locales */ |
| 467 | if ( (flags & ANYOFL_FOLD) |
| 468 | && av_tindex_skip_len_mg(av) >= ONLY_LOCALE_MATCHES_INDEX) |
| 469 | { |
| 470 | only_utf8_locale_invlist = ary[ONLY_LOCALE_MATCHES_INDEX]; |
| 471 | } |
| 472 | } |
| 473 | |
| 474 | if (! invlist) { |
| 475 | invlist = sv_2mortal(_new_invlist(0)); |
| 476 | } |
| 477 | |
| 478 | /* An ANYOF node contains a bitmap for the first NUM_ANYOF_CODE_POINTS |
| 479 | * code points, and an inversion list for the others, but if there are code |
| 480 | * points that should match only conditionally on the target string being |
| 481 | * UTF-8, those are placed in the inversion list, and not the bitmap. |
| 482 | * Since there are circumstances under which they could match, they are |
| 483 | * included in the SSC. But if the ANYOF node is to be inverted, we have |
| 484 | * to exclude them here, so that when we invert below, the end result |
| 485 | * actually does include them. (Think about "\xe0" =~ /[^\xc0]/di;). We |
| 486 | * have to do this here before we add the unconditionally matched code |
| 487 | * points */ |
| 488 | if (flags & ANYOF_INVERT) { |
| 489 | _invlist_intersection_complement_2nd(invlist, |
| 490 | PL_UpperLatin1, |
| 491 | &invlist); |
| 492 | } |
| 493 | |
| 494 | /* Add in the points from the bit map */ |
| 495 | if (REGNODE_TYPE(OP(node)) == ANYOF){ |
| 496 | for (unsigned i = 0; i < NUM_ANYOF_CODE_POINTS; i++) { |
| 497 | if (ANYOF_BITMAP_TEST(node, i)) { |
| 498 | unsigned int start = i++; |
| 499 | |
| 500 | for (; i < NUM_ANYOF_CODE_POINTS |
| 501 | && ANYOF_BITMAP_TEST(node, i); ++i) |
| 502 | { |
| 503 | /* empty */ |
| 504 | } |
| 505 | invlist = _add_range_to_invlist(invlist, start, i-1); |
| 506 | new_node_has_latin1 = TRUE; |
| 507 | } |
| 508 | } |
| 509 | } |
| 510 | |
| 511 | /* If this can match all upper Latin1 code points, have to add them |
| 512 | * as well. But don't add them if inverting, as when that gets done below, |
| 513 | * it would exclude all these characters, including the ones it shouldn't |
| 514 | * that were added just above */ |
| 515 | if ( ! (flags & ANYOF_INVERT) |
| 516 | && OP(node) == ANYOFD |
| 517 | && (flags & ANYOFD_NON_UTF8_MATCHES_ALL_NON_ASCII__shared)) |
| 518 | { |
| 519 | _invlist_union(invlist, PL_UpperLatin1, &invlist); |
| 520 | } |
| 521 | |
| 522 | /* Similarly for these */ |
| 523 | if (ANYOF_MATCHES_ALL_OUTSIDE_BITMAP(node)) { |
| 524 | _invlist_union_complement_2nd(invlist, PL_InBitmap, &invlist); |
| 525 | } |
| 526 | |
| 527 | if (flags & ANYOF_INVERT) { |
| 528 | _invlist_invert(invlist); |
| 529 | } |
| 530 | else if (flags & ANYOFL_FOLD) { |
| 531 | if (new_node_has_latin1) { |
| 532 | |
| 533 | /* These folds are potential in Turkic locales */ |
| 534 | if (_invlist_contains_cp(invlist, 'i')) { |
| 535 | invlist = add_cp_to_invlist(invlist, |
| 536 | LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE); |
| 537 | } |
| 538 | if (_invlist_contains_cp(invlist, 'I')) { |
| 539 | invlist = add_cp_to_invlist(invlist, |
| 540 | LATIN_SMALL_LETTER_DOTLESS_I); |
| 541 | } |
| 542 | |
| 543 | /* Under /li, any 0-255 could fold to any other 0-255, depending on |
| 544 | * the locale. We can skip this if there are no 0-255 at all. */ |
| 545 | _invlist_union(invlist, PL_Latin1, &invlist); |
| 546 | } |
| 547 | else { |
| 548 | if (_invlist_contains_cp(invlist, LATIN_SMALL_LETTER_DOTLESS_I)) { |
| 549 | invlist = add_cp_to_invlist(invlist, 'I'); |
| 550 | } |
| 551 | if (_invlist_contains_cp(invlist, |
| 552 | LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE)) |
| 553 | { |
| 554 | invlist = add_cp_to_invlist(invlist, 'i'); |
| 555 | } |
| 556 | } |
| 557 | } |
| 558 | |
| 559 | /* Similarly add the UTF-8 locale possible matches. These have to be |
| 560 | * deferred until after the non-UTF-8 locale ones are taken care of just |
| 561 | * above, or it leads to wrong results under ANYOF_INVERT */ |
| 562 | if (only_utf8_locale_invlist) { |
| 563 | _invlist_union_maybe_complement_2nd(invlist, |
| 564 | only_utf8_locale_invlist, |
| 565 | flags & ANYOF_INVERT, |
| 566 | &invlist); |
| 567 | } |
| 568 | |
| 569 | return invlist; |
| 570 | } |
| 571 | |
| 572 | /* 'AND' a given class with another one. Can create false positives. 'ssc' |
| 573 | * should not be inverted. */ |
| 574 | |
| 575 | STATIC void |
| 576 | S_ssc_and(pTHX_ const RExC_state_t *pRExC_state, regnode_ssc *ssc, |
| 577 | const regnode_charclass *and_with) |
| 578 | { |
| 579 | /* Accumulate into SSC 'ssc' its 'AND' with 'and_with', which is either |
| 580 | * another SSC or a regular ANYOF class. Can create false positives. */ |
| 581 | |
| 582 | SV* anded_cp_list; |
| 583 | U8 and_with_flags = (REGNODE_TYPE(OP(and_with)) == ANYOF) |
| 584 | ? ANYOF_FLAGS(and_with) |
| 585 | : 0; |
| 586 | U8 anded_flags; |
| 587 | |
| 588 | PERL_ARGS_ASSERT_SSC_AND; |
| 589 | |
| 590 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 591 | |
| 592 | /* 'and_with' is used as-is if it too is an SSC; otherwise have to extract |
| 593 | * the code point inversion list and just the relevant flags */ |
| 594 | if (is_ANYOF_SYNTHETIC(and_with)) { |
| 595 | anded_cp_list = ((regnode_ssc *)and_with)->invlist; |
| 596 | anded_flags = and_with_flags; |
| 597 | |
| 598 | /* XXX This is a kludge around what appears to be deficiencies in the |
| 599 | * optimizer. If we make S_ssc_anything() add in the WARN_SUPER flag, |
| 600 | * there are paths through the optimizer where it doesn't get weeded |
| 601 | * out when it should. And if we don't make some extra provision for |
| 602 | * it like the code just below, it doesn't get added when it should. |
| 603 | * This solution is to add it only when AND'ing, which is here, and |
| 604 | * only when what is being AND'ed is the pristine, original node |
| 605 | * matching anything. Thus it is like adding it to ssc_anything() but |
| 606 | * only when the result is to be AND'ed. Probably the same solution |
| 607 | * could be adopted for the same problem we have with /l matching, |
| 608 | * which is solved differently in S_ssc_init(), and that would lead to |
| 609 | * fewer false positives than that solution has. But if this solution |
| 610 | * creates bugs, the consequences are only that a warning isn't raised |
| 611 | * that should be; while the consequences for having /l bugs is |
| 612 | * incorrect matches */ |
| 613 | if (ssc_is_anything((regnode_ssc *)and_with)) { |
| 614 | anded_flags |= ANYOF_WARN_SUPER__shared; |
| 615 | } |
| 616 | } |
| 617 | else { |
| 618 | anded_cp_list = get_ANYOF_cp_list_for_ssc(pRExC_state, and_with); |
| 619 | if (OP(and_with) == ANYOFD) { |
| 620 | anded_flags = and_with_flags & ANYOF_COMMON_FLAGS; |
| 621 | } |
| 622 | else { |
| 623 | anded_flags = and_with_flags |
| 624 | & ( ANYOF_COMMON_FLAGS |
| 625 | |ANYOFD_NON_UTF8_MATCHES_ALL_NON_ASCII__shared |
| 626 | |ANYOF_HAS_EXTRA_RUNTIME_MATCHES); |
| 627 | if (and_with_flags & ANYOFL_UTF8_LOCALE_REQD) { |
| 628 | anded_flags &= ANYOF_HAS_EXTRA_RUNTIME_MATCHES; |
| 629 | } |
| 630 | } |
| 631 | } |
| 632 | |
| 633 | ANYOF_FLAGS(ssc) &= anded_flags; |
| 634 | |
| 635 | /* Below, C1 is the list of code points in 'ssc'; P1, its posix classes. |
| 636 | * C2 is the list of code points in 'and-with'; P2, its posix classes. |
| 637 | * 'and_with' may be inverted. When not inverted, we have the situation of |
| 638 | * computing: |
| 639 | * (C1 | P1) & (C2 | P2) |
| 640 | * = (C1 & (C2 | P2)) | (P1 & (C2 | P2)) |
| 641 | * = ((C1 & C2) | (C1 & P2)) | ((P1 & C2) | (P1 & P2)) |
| 642 | * <= ((C1 & C2) | P2)) | ( P1 | (P1 & P2)) |
| 643 | * <= ((C1 & C2) | P1 | P2) |
| 644 | * Alternatively, the last few steps could be: |
| 645 | * = ((C1 & C2) | (C1 & P2)) | ((P1 & C2) | (P1 & P2)) |
| 646 | * <= ((C1 & C2) | C1 ) | ( C2 | (P1 & P2)) |
| 647 | * <= (C1 | C2 | (P1 & P2)) |
| 648 | * We favor the second approach if either P1 or P2 is non-empty. This is |
| 649 | * because these components are a barrier to doing optimizations, as what |
| 650 | * they match cannot be known until the moment of matching as they are |
| 651 | * dependent on the current locale, 'AND"ing them likely will reduce or |
| 652 | * eliminate them. |
| 653 | * But we can do better if we know that C1,P1 are in their initial state (a |
| 654 | * frequent occurrence), each matching everything: |
| 655 | * (<everything>) & (C2 | P2) = C2 | P2 |
| 656 | * Similarly, if C2,P2 are in their initial state (again a frequent |
| 657 | * occurrence), the result is a no-op |
| 658 | * (C1 | P1) & (<everything>) = C1 | P1 |
| 659 | * |
| 660 | * Inverted, we have |
| 661 | * (C1 | P1) & ~(C2 | P2) = (C1 | P1) & (~C2 & ~P2) |
| 662 | * = (C1 & (~C2 & ~P2)) | (P1 & (~C2 & ~P2)) |
| 663 | * <= (C1 & ~C2) | (P1 & ~P2) |
| 664 | * */ |
| 665 | |
| 666 | if ((and_with_flags & ANYOF_INVERT) |
| 667 | && ! is_ANYOF_SYNTHETIC(and_with)) |
| 668 | { |
| 669 | unsigned int i; |
| 670 | |
| 671 | ssc_intersection(ssc, |
| 672 | anded_cp_list, |
| 673 | FALSE /* Has already been inverted */ |
| 674 | ); |
| 675 | |
| 676 | /* If either P1 or P2 is empty, the intersection will be also; can skip |
| 677 | * the loop */ |
| 678 | if (! (and_with_flags & ANYOF_MATCHES_POSIXL)) { |
| 679 | ANYOF_POSIXL_ZERO(ssc); |
| 680 | } |
| 681 | else if (ANYOF_POSIXL_SSC_TEST_ANY_SET(ssc)) { |
| 682 | |
| 683 | /* Note that the Posix class component P from 'and_with' actually |
| 684 | * looks like: |
| 685 | * P = Pa | Pb | ... | Pn |
| 686 | * where each component is one posix class, such as in [\w\s]. |
| 687 | * Thus |
| 688 | * ~P = ~(Pa | Pb | ... | Pn) |
| 689 | * = ~Pa & ~Pb & ... & ~Pn |
| 690 | * <= ~Pa | ~Pb | ... | ~Pn |
| 691 | * The last is something we can easily calculate, but unfortunately |
| 692 | * is likely to have many false positives. We could do better |
| 693 | * in some (but certainly not all) instances if two classes in |
| 694 | * P have known relationships. For example |
| 695 | * :lower: <= :alpha: <= :alnum: <= \w <= :graph: <= :print: |
| 696 | * So |
| 697 | * :lower: & :print: = :lower: |
| 698 | * And similarly for classes that must be disjoint. For example, |
| 699 | * since \s and \w can have no elements in common based on rules in |
| 700 | * the POSIX standard, |
| 701 | * \w & ^\S = nothing |
| 702 | * Unfortunately, some vendor locales do not meet the Posix |
| 703 | * standard, in particular almost everything by Microsoft. |
| 704 | * The loop below just changes e.g., \w into \W and vice versa */ |
| 705 | |
| 706 | regnode_charclass_posixl temp; |
| 707 | int add = 1; /* To calculate the index of the complement */ |
| 708 | |
| 709 | Zero(&temp, 1, regnode_charclass_posixl); |
| 710 | ANYOF_POSIXL_ZERO(&temp); |
| 711 | for (i = 0; i < ANYOF_MAX; i++) { |
| 712 | assert(i % 2 != 0 |
| 713 | || ! ANYOF_POSIXL_TEST((regnode_charclass_posixl*) and_with, i) |
| 714 | || ! ANYOF_POSIXL_TEST((regnode_charclass_posixl*) and_with, i + 1)); |
| 715 | |
| 716 | if (ANYOF_POSIXL_TEST((regnode_charclass_posixl*) and_with, i)) { |
| 717 | ANYOF_POSIXL_SET(&temp, i + add); |
| 718 | } |
| 719 | add = 0 - add; /* 1 goes to -1; -1 goes to 1 */ |
| 720 | } |
| 721 | ANYOF_POSIXL_AND(&temp, ssc); |
| 722 | |
| 723 | } /* else ssc already has no posixes */ |
| 724 | } /* else: Not inverted. This routine is a no-op if 'and_with' is an SSC |
| 725 | in its initial state */ |
| 726 | else if (! is_ANYOF_SYNTHETIC(and_with) |
| 727 | || ! ssc_is_cp_posixl_init(pRExC_state, (regnode_ssc *)and_with)) |
| 728 | { |
| 729 | /* But if 'ssc' is in its initial state, the result is just 'and_with'; |
| 730 | * copy it over 'ssc' */ |
| 731 | if (ssc_is_cp_posixl_init(pRExC_state, ssc)) { |
| 732 | if (is_ANYOF_SYNTHETIC(and_with)) { |
| 733 | StructCopy(and_with, ssc, regnode_ssc); |
| 734 | } |
| 735 | else { |
| 736 | ssc->invlist = anded_cp_list; |
| 737 | ANYOF_POSIXL_ZERO(ssc); |
| 738 | if (and_with_flags & ANYOF_MATCHES_POSIXL) { |
| 739 | ANYOF_POSIXL_OR((regnode_charclass_posixl*) and_with, ssc); |
| 740 | } |
| 741 | } |
| 742 | } |
| 743 | else if (ANYOF_POSIXL_SSC_TEST_ANY_SET(ssc) |
| 744 | || (and_with_flags & ANYOF_MATCHES_POSIXL)) |
| 745 | { |
| 746 | /* One or the other of P1, P2 is non-empty. */ |
| 747 | if (and_with_flags & ANYOF_MATCHES_POSIXL) { |
| 748 | ANYOF_POSIXL_AND((regnode_charclass_posixl*) and_with, ssc); |
| 749 | } |
| 750 | ssc_union(ssc, anded_cp_list, FALSE); |
| 751 | } |
| 752 | else { /* P1 = P2 = empty */ |
| 753 | ssc_intersection(ssc, anded_cp_list, FALSE); |
| 754 | } |
| 755 | } |
| 756 | } |
| 757 | |
| 758 | STATIC void |
| 759 | S_ssc_or(pTHX_ const RExC_state_t *pRExC_state, regnode_ssc *ssc, |
| 760 | const regnode_charclass *or_with) |
| 761 | { |
| 762 | /* Accumulate into SSC 'ssc' its 'OR' with 'or_with', which is either |
| 763 | * another SSC or a regular ANYOF class. Can create false positives if |
| 764 | * 'or_with' is to be inverted. */ |
| 765 | |
| 766 | SV* ored_cp_list; |
| 767 | U8 ored_flags; |
| 768 | U8 or_with_flags = (REGNODE_TYPE(OP(or_with)) == ANYOF) |
| 769 | ? ANYOF_FLAGS(or_with) |
| 770 | : 0; |
| 771 | |
| 772 | PERL_ARGS_ASSERT_SSC_OR; |
| 773 | |
| 774 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 775 | |
| 776 | /* 'or_with' is used as-is if it too is an SSC; otherwise have to extract |
| 777 | * the code point inversion list and just the relevant flags */ |
| 778 | if (is_ANYOF_SYNTHETIC(or_with)) { |
| 779 | ored_cp_list = ((regnode_ssc*) or_with)->invlist; |
| 780 | ored_flags = or_with_flags; |
| 781 | } |
| 782 | else { |
| 783 | ored_cp_list = get_ANYOF_cp_list_for_ssc(pRExC_state, or_with); |
| 784 | ored_flags = or_with_flags & ANYOF_COMMON_FLAGS; |
| 785 | if (OP(or_with) != ANYOFD) { |
| 786 | ored_flags |= |
| 787 | or_with_flags & ( ANYOFD_NON_UTF8_MATCHES_ALL_NON_ASCII__shared |
| 788 | |ANYOF_HAS_EXTRA_RUNTIME_MATCHES); |
| 789 | if (or_with_flags & ANYOFL_UTF8_LOCALE_REQD) { |
| 790 | ored_flags |= ANYOF_HAS_EXTRA_RUNTIME_MATCHES; |
| 791 | } |
| 792 | } |
| 793 | } |
| 794 | |
| 795 | ANYOF_FLAGS(ssc) |= ored_flags; |
| 796 | |
| 797 | /* Below, C1 is the list of code points in 'ssc'; P1, its posix classes. |
| 798 | * C2 is the list of code points in 'or-with'; P2, its posix classes. |
| 799 | * 'or_with' may be inverted. When not inverted, we have the simple |
| 800 | * situation of computing: |
| 801 | * (C1 | P1) | (C2 | P2) = (C1 | C2) | (P1 | P2) |
| 802 | * If P1|P2 yields a situation with both a class and its complement are |
| 803 | * set, like having both \w and \W, this matches all code points, and we |
| 804 | * can delete these from the P component of the ssc going forward. XXX We |
| 805 | * might be able to delete all the P components, but I (khw) am not certain |
| 806 | * about this, and it is better to be safe. |
| 807 | * |
| 808 | * Inverted, we have |
| 809 | * (C1 | P1) | ~(C2 | P2) = (C1 | P1) | (~C2 & ~P2) |
| 810 | * <= (C1 | P1) | ~C2 |
| 811 | * <= (C1 | ~C2) | P1 |
| 812 | * (which results in actually simpler code than the non-inverted case) |
| 813 | * */ |
| 814 | |
| 815 | if ((or_with_flags & ANYOF_INVERT) |
| 816 | && ! is_ANYOF_SYNTHETIC(or_with)) |
| 817 | { |
| 818 | /* We ignore P2, leaving P1 going forward */ |
| 819 | } /* else Not inverted */ |
| 820 | else if (or_with_flags & ANYOF_MATCHES_POSIXL) { |
| 821 | ANYOF_POSIXL_OR((regnode_charclass_posixl*)or_with, ssc); |
| 822 | if (ANYOF_POSIXL_SSC_TEST_ANY_SET(ssc)) { |
| 823 | unsigned int i; |
| 824 | for (i = 0; i < ANYOF_MAX; i += 2) { |
| 825 | if (ANYOF_POSIXL_TEST(ssc, i) && ANYOF_POSIXL_TEST(ssc, i + 1)) |
| 826 | { |
| 827 | ssc_match_all_cp(ssc); |
| 828 | ANYOF_POSIXL_CLEAR(ssc, i); |
| 829 | ANYOF_POSIXL_CLEAR(ssc, i+1); |
| 830 | } |
| 831 | } |
| 832 | } |
| 833 | } |
| 834 | |
| 835 | ssc_union(ssc, |
| 836 | ored_cp_list, |
| 837 | FALSE /* Already has been inverted */ |
| 838 | ); |
| 839 | } |
| 840 | |
| 841 | STATIC void |
| 842 | S_ssc_union(pTHX_ regnode_ssc *ssc, SV* const invlist, const bool invert2nd) |
| 843 | { |
| 844 | PERL_ARGS_ASSERT_SSC_UNION; |
| 845 | |
| 846 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 847 | |
| 848 | _invlist_union_maybe_complement_2nd(ssc->invlist, |
| 849 | invlist, |
| 850 | invert2nd, |
| 851 | &ssc->invlist); |
| 852 | } |
| 853 | |
| 854 | STATIC void |
| 855 | S_ssc_intersection(pTHX_ regnode_ssc *ssc, |
| 856 | SV* const invlist, |
| 857 | const bool invert2nd) |
| 858 | { |
| 859 | PERL_ARGS_ASSERT_SSC_INTERSECTION; |
| 860 | |
| 861 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 862 | |
| 863 | _invlist_intersection_maybe_complement_2nd(ssc->invlist, |
| 864 | invlist, |
| 865 | invert2nd, |
| 866 | &ssc->invlist); |
| 867 | } |
| 868 | |
| 869 | STATIC void |
| 870 | S_ssc_add_range(pTHX_ regnode_ssc *ssc, const UV start, const UV end) |
| 871 | { |
| 872 | PERL_ARGS_ASSERT_SSC_ADD_RANGE; |
| 873 | |
| 874 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 875 | |
| 876 | ssc->invlist = _add_range_to_invlist(ssc->invlist, start, end); |
| 877 | } |
| 878 | |
| 879 | STATIC void |
| 880 | S_ssc_cp_and(pTHX_ regnode_ssc *ssc, const UV cp) |
| 881 | { |
| 882 | /* AND just the single code point 'cp' into the SSC 'ssc' */ |
| 883 | |
| 884 | SV* cp_list = _new_invlist(2); |
| 885 | |
| 886 | PERL_ARGS_ASSERT_SSC_CP_AND; |
| 887 | |
| 888 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 889 | |
| 890 | cp_list = add_cp_to_invlist(cp_list, cp); |
| 891 | ssc_intersection(ssc, cp_list, |
| 892 | FALSE /* Not inverted */ |
| 893 | ); |
| 894 | SvREFCNT_dec_NN(cp_list); |
| 895 | } |
| 896 | |
| 897 | STATIC void |
| 898 | S_ssc_clear_locale(regnode_ssc *ssc) |
| 899 | { |
| 900 | /* Set the SSC 'ssc' to not match any locale things */ |
| 901 | PERL_ARGS_ASSERT_SSC_CLEAR_LOCALE; |
| 902 | |
| 903 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 904 | |
| 905 | ANYOF_POSIXL_ZERO(ssc); |
| 906 | ANYOF_FLAGS(ssc) &= ~ANYOF_LOCALE_FLAGS; |
| 907 | } |
| 908 | |
| 909 | bool |
| 910 | Perl_is_ssc_worth_it(const RExC_state_t * pRExC_state, const regnode_ssc * ssc) |
| 911 | { |
| 912 | /* The synthetic start class is used to hopefully quickly winnow down |
| 913 | * places where a pattern could start a match in the target string. If it |
| 914 | * doesn't really narrow things down that much, there isn't much point to |
| 915 | * having the overhead of using it. This function uses some very crude |
| 916 | * heuristics to decide if to use the ssc or not. |
| 917 | * |
| 918 | * It returns TRUE if 'ssc' rules out more than half what it considers to |
| 919 | * be the "likely" possible matches, but of course it doesn't know what the |
| 920 | * actual things being matched are going to be; these are only guesses |
| 921 | * |
| 922 | * For /l matches, it assumes that the only likely matches are going to be |
| 923 | * in the 0-255 range, uniformly distributed, so half of that is 127 |
| 924 | * For /a and /d matches, it assumes that the likely matches will be just |
| 925 | * the ASCII range, so half of that is 63 |
| 926 | * For /u and there isn't anything matching above the Latin1 range, it |
| 927 | * assumes that that is the only range likely to be matched, and uses |
| 928 | * half that as the cut-off: 127. If anything matches above Latin1, |
| 929 | * it assumes that all of Unicode could match (uniformly), except for |
| 930 | * non-Unicode code points and things in the General Category "Other" |
| 931 | * (unassigned, private use, surrogates, controls and formats). This |
| 932 | * is a much large number. */ |
| 933 | |
| 934 | U32 count = 0; /* Running total of number of code points matched by |
| 935 | 'ssc' */ |
| 936 | UV start, end; /* Start and end points of current range in inversion |
| 937 | XXX outdated. UTF-8 locales are common, what about invert? list */ |
| 938 | const U32 max_code_points = (LOC) |
| 939 | ? 256 |
| 940 | : (( ! UNI_SEMANTICS |
| 941 | || invlist_highest(ssc->invlist) < 256) |
| 942 | ? 128 |
| 943 | : NON_OTHER_COUNT); |
| 944 | const U32 max_match = max_code_points / 2; |
| 945 | |
| 946 | PERL_ARGS_ASSERT_IS_SSC_WORTH_IT; |
| 947 | |
| 948 | invlist_iterinit(ssc->invlist); |
| 949 | while (invlist_iternext(ssc->invlist, &start, &end)) { |
| 950 | if (start >= max_code_points) { |
| 951 | break; |
| 952 | } |
| 953 | end = MIN(end, max_code_points - 1); |
| 954 | count += end - start + 1; |
| 955 | if (count >= max_match) { |
| 956 | invlist_iterfinish(ssc->invlist); |
| 957 | return FALSE; |
| 958 | } |
| 959 | } |
| 960 | |
| 961 | return TRUE; |
| 962 | } |
| 963 | |
| 964 | |
| 965 | void |
| 966 | Perl_ssc_finalize(pTHX_ RExC_state_t *pRExC_state, regnode_ssc *ssc) |
| 967 | { |
| 968 | /* The inversion list in the SSC is marked mortal; now we need a more |
| 969 | * permanent copy, which is stored the same way that is done in a regular |
| 970 | * ANYOF node, with the first NUM_ANYOF_CODE_POINTS code points in a bit |
| 971 | * map */ |
| 972 | |
| 973 | SV* invlist = invlist_clone(ssc->invlist, NULL); |
| 974 | |
| 975 | PERL_ARGS_ASSERT_SSC_FINALIZE; |
| 976 | |
| 977 | assert(is_ANYOF_SYNTHETIC(ssc)); |
| 978 | |
| 979 | /* The code in this file assumes that all but these flags aren't relevant |
| 980 | * to the SSC, except SSC_MATCHES_EMPTY_STRING, which should be cleared |
| 981 | * by the time we reach here */ |
| 982 | assert(! (ANYOF_FLAGS(ssc) |
| 983 | & ~( ANYOF_COMMON_FLAGS |
| 984 | |ANYOFD_NON_UTF8_MATCHES_ALL_NON_ASCII__shared |
| 985 | |ANYOF_HAS_EXTRA_RUNTIME_MATCHES))); |
| 986 | |
| 987 | populate_anyof_bitmap_from_invlist( (regnode *) ssc, &invlist); |
| 988 | |
| 989 | set_ANYOF_arg(pRExC_state, (regnode *) ssc, invlist, NULL, NULL); |
| 990 | SvREFCNT_dec(invlist); |
| 991 | |
| 992 | /* Make sure is clone-safe */ |
| 993 | ssc->invlist = NULL; |
| 994 | |
| 995 | if (ANYOF_POSIXL_SSC_TEST_ANY_SET(ssc)) { |
| 996 | ANYOF_FLAGS(ssc) |= ANYOF_MATCHES_POSIXL; |
| 997 | OP(ssc) = ANYOFPOSIXL; |
| 998 | } |
| 999 | else if (RExC_contains_locale) { |
| 1000 | OP(ssc) = ANYOFL; |
| 1001 | } |
| 1002 | |
| 1003 | assert(! (ANYOF_FLAGS(ssc) & ANYOF_LOCALE_FLAGS) || RExC_contains_locale); |
| 1004 | } |
| 1005 | |
| 1006 | /* The below joins as many adjacent EXACTish nodes as possible into a single |
| 1007 | * one. The regop may be changed if the node(s) contain certain sequences that |
| 1008 | * require special handling. The joining is only done if: |
| 1009 | * 1) there is room in the current conglomerated node to entirely contain the |
| 1010 | * next one. |
| 1011 | * 2) they are compatible node types |
| 1012 | * |
| 1013 | * The adjacent nodes actually may be separated by NOTHING-kind nodes, and |
| 1014 | * these get optimized out |
| 1015 | * |
| 1016 | * XXX khw thinks this should be enhanced to fill EXACT (at least) nodes as full |
| 1017 | * as possible, even if that means splitting an existing node so that its first |
| 1018 | * part is moved to the preceding node. This would maximise the efficiency of |
| 1019 | * memEQ during matching. |
| 1020 | * |
| 1021 | * If a node is to match under /i (folded), the number of characters it matches |
| 1022 | * can be different than its character length if it contains a multi-character |
| 1023 | * fold. *min_subtract is set to the total delta number of characters of the |
| 1024 | * input nodes. |
| 1025 | * |
| 1026 | * And *unfolded_multi_char is set to indicate whether or not the node contains |
| 1027 | * an unfolded multi-char fold. This happens when it won't be known until |
| 1028 | * runtime whether the fold is valid or not; namely |
| 1029 | * 1) for EXACTF nodes that contain LATIN SMALL LETTER SHARP S, as only if the |
| 1030 | * target string being matched against turns out to be UTF-8 is that fold |
| 1031 | * valid; or |
| 1032 | * 2) for EXACTFL nodes whose folding rules depend on the locale in force at |
| 1033 | * runtime. |
| 1034 | * (Multi-char folds whose components are all above the Latin1 range are not |
| 1035 | * run-time locale dependent, and have already been folded by the time this |
| 1036 | * function is called.) |
| 1037 | * |
| 1038 | * This is as good a place as any to discuss the design of handling these |
| 1039 | * multi-character fold sequences. It's been wrong in Perl for a very long |
| 1040 | * time. There are three code points in Unicode whose multi-character folds |
| 1041 | * were long ago discovered to mess things up. The previous designs for |
| 1042 | * dealing with these involved assigning a special node for them. This |
| 1043 | * approach doesn't always work, as evidenced by this example: |
| 1044 | * "\xDFs" =~ /s\xDF/ui # Used to fail before these patches |
| 1045 | * Both sides fold to "sss", but if the pattern is parsed to create a node that |
| 1046 | * would match just the \xDF, it won't be able to handle the case where a |
| 1047 | * successful match would have to cross the node's boundary. The new approach |
| 1048 | * that hopefully generally solves the problem generates an EXACTFUP node |
| 1049 | * that is "sss" in this case. |
| 1050 | * |
| 1051 | * It turns out that there are problems with all multi-character folds, and not |
| 1052 | * just these three. Now the code is general, for all such cases. The |
| 1053 | * approach taken is: |
| 1054 | * 1) This routine examines each EXACTFish node that could contain multi- |
| 1055 | * character folded sequences. Since a single character can fold into |
| 1056 | * such a sequence, the minimum match length for this node is less than |
| 1057 | * the number of characters in the node. This routine returns in |
| 1058 | * *min_subtract how many characters to subtract from the actual |
| 1059 | * length of the string to get a real minimum match length; it is 0 if |
| 1060 | * there are no multi-char foldeds. This delta is used by the caller to |
| 1061 | * adjust the min length of the match, and the delta between min and max, |
| 1062 | * so that the optimizer doesn't reject these possibilities based on size |
| 1063 | * constraints. |
| 1064 | * |
| 1065 | * 2) For the sequence involving the LATIN SMALL LETTER SHARP S (U+00DF) |
| 1066 | * under /u, we fold it to 'ss' in regatom(), and in this routine, after |
| 1067 | * joining, we scan for occurrences of the sequence 'ss' in non-UTF-8 |
| 1068 | * EXACTFU nodes. The node type of such nodes is then changed to |
| 1069 | * EXACTFUP, indicating it is problematic, and needs careful handling. |
| 1070 | * (The procedures in step 1) above are sufficient to handle this case in |
| 1071 | * UTF-8 encoded nodes.) The reason this is problematic is that this is |
| 1072 | * the only case where there is a possible fold length change in non-UTF-8 |
| 1073 | * patterns. By reserving a special node type for problematic cases, the |
| 1074 | * far more common regular EXACTFU nodes can be processed faster. |
| 1075 | * regexec.c takes advantage of this. |
| 1076 | * |
| 1077 | * EXACTFUP has been created as a grab-bag for (hopefully uncommon) |
| 1078 | * problematic cases. These all only occur when the pattern is not |
| 1079 | * UTF-8. In addition to the 'ss' sequence where there is a possible fold |
| 1080 | * length change, it handles the situation where the string cannot be |
| 1081 | * entirely folded. The strings in an EXACTFish node are folded as much |
| 1082 | * as possible during compilation in regcomp.c. This saves effort in |
| 1083 | * regex matching. By using an EXACTFUP node when it is not possible to |
| 1084 | * fully fold at compile time, regexec.c can know that everything in an |
| 1085 | * EXACTFU node is folded, so folding can be skipped at runtime. The only |
| 1086 | * case where folding in EXACTFU nodes can't be done at compile time is |
| 1087 | * the presumably uncommon MICRO SIGN, when the pattern isn't UTF-8. This |
| 1088 | * is because its fold requires UTF-8 to represent. Thus EXACTFUP nodes |
| 1089 | * handle two very different cases. Alternatively, there could have been |
| 1090 | * a node type where there are length changes, one for unfolded, and one |
| 1091 | * for both. If yet another special case needed to be created, the number |
| 1092 | * of required node types would have to go to 7. khw figures that even |
| 1093 | * though there are plenty of node types to spare, that the maintenance |
| 1094 | * cost wasn't worth the small speedup of doing it that way, especially |
| 1095 | * since he thinks the MICRO SIGN is rarely encountered in practice. |
| 1096 | * |
| 1097 | * There are other cases where folding isn't done at compile time, but |
| 1098 | * none of them are under /u, and hence not for EXACTFU nodes. The folds |
| 1099 | * in EXACTFL nodes aren't known until runtime, and vary as the locale |
| 1100 | * changes. Some folds in EXACTF depend on if the runtime target string |
| 1101 | * is UTF-8 or not. (regatom() will create an EXACTFU node even under /di |
| 1102 | * when no fold in it depends on the UTF-8ness of the target string.) |
| 1103 | * |
| 1104 | * 3) A problem remains for unfolded multi-char folds. (These occur when the |
| 1105 | * validity of the fold won't be known until runtime, and so must remain |
| 1106 | * unfolded for now. This happens for the sharp s in EXACTF and EXACTFAA |
| 1107 | * nodes when the pattern isn't in UTF-8. (Note, BTW, that there cannot |
| 1108 | * be an EXACTF node with a UTF-8 pattern.) They also occur for various |
| 1109 | * folds in EXACTFL nodes, regardless of the UTF-ness of the pattern.) |
| 1110 | * The reason this is a problem is that the optimizer part of regexec.c |
| 1111 | * (probably unwittingly, in Perl_regexec_flags()) makes an assumption |
| 1112 | * that a character in the pattern corresponds to at most a single |
| 1113 | * character in the target string. (And I do mean character, and not byte |
| 1114 | * here, unlike other parts of the documentation that have never been |
| 1115 | * updated to account for multibyte Unicode.) Sharp s in EXACTF and |
| 1116 | * EXACTFL nodes can match the two character string 'ss'; in EXACTFAA |
| 1117 | * nodes it can match "\x{17F}\x{17F}". These, along with other ones in |
| 1118 | * EXACTFL nodes, violate the assumption, and they are the only instances |
| 1119 | * where it is violated. I'm reluctant to try to change the assumption, |
| 1120 | * as the code involved is impenetrable to me (khw), so instead the code |
| 1121 | * here punts. This routine examines EXACTFL nodes, and (when the pattern |
| 1122 | * isn't UTF-8) EXACTF and EXACTFAA for such unfolded folds, and returns a |
| 1123 | * boolean indicating whether or not the node contains such a fold. When |
| 1124 | * it is true, the caller sets a flag that later causes the optimizer in |
| 1125 | * this file to not set values for the floating and fixed string lengths, |
| 1126 | * and thus avoids the optimizer code in regexec.c that makes the invalid |
| 1127 | * assumption. Thus, there is no optimization based on string lengths for |
| 1128 | * EXACTFL nodes that contain these few folds, nor for non-UTF8-pattern |
| 1129 | * EXACTF and EXACTFAA nodes that contain the sharp s. (The reason the |
| 1130 | * assumption is wrong only in these cases is that all other non-UTF-8 |
| 1131 | * folds are 1-1; and, for UTF-8 patterns, we pre-fold all other folds to |
| 1132 | * their expanded versions. (Again, we can't prefold sharp s to 'ss' in |
| 1133 | * EXACTF nodes because we don't know at compile time if it actually |
| 1134 | * matches 'ss' or not. For EXACTF nodes it will match iff the target |
| 1135 | * string is in UTF-8. This is in contrast to EXACTFU nodes, where it |
| 1136 | * always matches; and EXACTFAA where it never does. In an EXACTFAA node |
| 1137 | * in a UTF-8 pattern, sharp s is folded to "\x{17F}\x{17F}, avoiding the |
| 1138 | * problem; but in a non-UTF8 pattern, folding it to that above-Latin1 |
| 1139 | * string would require the pattern to be forced into UTF-8, the overhead |
| 1140 | * of which we want to avoid. Similarly the unfolded multi-char folds in |
| 1141 | * EXACTFL nodes will match iff the locale at the time of match is a UTF-8 |
| 1142 | * locale.) |
| 1143 | * |
| 1144 | * Similarly, the code that generates tries doesn't currently handle |
| 1145 | * not-already-folded multi-char folds, and it looks like a pain to change |
| 1146 | * that. Therefore, trie generation of EXACTFAA nodes with the sharp s |
| 1147 | * doesn't work. Instead, such an EXACTFAA is turned into a new regnode, |
| 1148 | * EXACTFAA_NO_TRIE, which the trie code knows not to handle. Most people |
| 1149 | * using /iaa matching will be doing so almost entirely with ASCII |
| 1150 | * strings, so this should rarely be encountered in practice */ |
| 1151 | |
| 1152 | U32 |
| 1153 | Perl_join_exact(pTHX_ RExC_state_t *pRExC_state, regnode *scan, |
| 1154 | UV *min_subtract, bool *unfolded_multi_char, |
| 1155 | U32 flags, regnode *val, U32 depth) |
| 1156 | { |
| 1157 | /* Merge several consecutive EXACTish nodes into one. */ |
| 1158 | |
| 1159 | regnode *n = regnext(scan); |
| 1160 | U32 stringok = 1; |
| 1161 | regnode *next = REGNODE_AFTER_varies(scan); |
| 1162 | U32 merged = 0; |
| 1163 | U32 stopnow = 0; |
| 1164 | #ifdef DEBUGGING |
| 1165 | regnode *stop = scan; |
| 1166 | DECLARE_AND_GET_RE_DEBUG_FLAGS; |
| 1167 | #else |
| 1168 | PERL_UNUSED_ARG(depth); |
| 1169 | #endif |
| 1170 | |
| 1171 | PERL_ARGS_ASSERT_JOIN_EXACT; |
| 1172 | #ifndef EXPERIMENTAL_INPLACESCAN |
| 1173 | PERL_UNUSED_ARG(flags); |
| 1174 | PERL_UNUSED_ARG(val); |
| 1175 | #endif |
| 1176 | DEBUG_PEEP("join", scan, depth, 0); |
| 1177 | |
| 1178 | assert(REGNODE_TYPE(OP(scan)) == EXACT); |
| 1179 | |
| 1180 | /* Look through the subsequent nodes in the chain. Skip NOTHING, merge |
| 1181 | * EXACT ones that are mergeable to the current one. */ |
| 1182 | while ( n |
| 1183 | && ( REGNODE_TYPE(OP(n)) == NOTHING |
| 1184 | || (stringok && REGNODE_TYPE(OP(n)) == EXACT)) |
| 1185 | && NEXT_OFF(n) |
| 1186 | && NEXT_OFF(scan) + NEXT_OFF(n) < I16_MAX) |
| 1187 | { |
| 1188 | |
| 1189 | if (OP(n) == TAIL || n > next) |
| 1190 | stringok = 0; |
| 1191 | if (REGNODE_TYPE(OP(n)) == NOTHING) { |
| 1192 | DEBUG_PEEP("skip:", n, depth, 0); |
| 1193 | NEXT_OFF(scan) += NEXT_OFF(n); |
| 1194 | next = n + NODE_STEP_REGNODE; |
| 1195 | #ifdef DEBUGGING |
| 1196 | if (stringok) |
| 1197 | stop = n; |
| 1198 | #endif |
| 1199 | n = regnext(n); |
| 1200 | } |
| 1201 | else if (stringok) { |
| 1202 | const unsigned int oldl = STR_LEN(scan); |
| 1203 | regnode * const nnext = regnext(n); |
| 1204 | |
| 1205 | /* XXX I (khw) kind of doubt that this works on platforms (should |
| 1206 | * Perl ever run on one) where U8_MAX is above 255 because of lots |
| 1207 | * of other assumptions */ |
| 1208 | /* Don't join if the sum can't fit into a single node */ |
| 1209 | if (oldl + STR_LEN(n) > U8_MAX) |
| 1210 | break; |
| 1211 | |
| 1212 | /* Joining something that requires UTF-8 with something that |
| 1213 | * doesn't, means the result requires UTF-8. */ |
| 1214 | if (OP(scan) == EXACT && (OP(n) == EXACT_REQ8)) { |
| 1215 | OP(scan) = EXACT_REQ8; |
| 1216 | } |
| 1217 | else if (OP(scan) == EXACT_REQ8 && (OP(n) == EXACT)) { |
| 1218 | ; /* join is compatible, no need to change OP */ |
| 1219 | } |
| 1220 | else if ((OP(scan) == EXACTFU) && (OP(n) == EXACTFU_REQ8)) { |
| 1221 | OP(scan) = EXACTFU_REQ8; |
| 1222 | } |
| 1223 | else if ((OP(scan) == EXACTFU_REQ8) && (OP(n) == EXACTFU)) { |
| 1224 | ; /* join is compatible, no need to change OP */ |
| 1225 | } |
| 1226 | else if (OP(scan) == EXACTFU && OP(n) == EXACTFU) { |
| 1227 | ; /* join is compatible, no need to change OP */ |
| 1228 | } |
| 1229 | else if (OP(scan) == EXACTFU && OP(n) == EXACTFU_S_EDGE) { |
| 1230 | |
| 1231 | /* Under /di, temporary EXACTFU_S_EDGE nodes are generated, |
| 1232 | * which can join with EXACTFU ones. We check for this case |
| 1233 | * here. These need to be resolved to either EXACTFU or |
| 1234 | * EXACTF at joining time. They have nothing in them that |
| 1235 | * would forbid them from being the more desirable EXACTFU |
| 1236 | * nodes except that they begin and/or end with a single [Ss]. |
| 1237 | * The reason this is problematic is because they could be |
| 1238 | * joined in this loop with an adjacent node that ends and/or |
| 1239 | * begins with [Ss] which would then form the sequence 'ss', |
| 1240 | * which matches differently under /di than /ui, in which case |
| 1241 | * EXACTFU can't be used. If the 'ss' sequence doesn't get |
| 1242 | * formed, the nodes get absorbed into any adjacent EXACTFU |
| 1243 | * node. And if the only adjacent node is EXACTF, they get |
| 1244 | * absorbed into that, under the theory that a longer node is |
| 1245 | * better than two shorter ones, even if one is EXACTFU. Note |
| 1246 | * that EXACTFU_REQ8 is generated only for UTF-8 patterns, |
| 1247 | * and the EXACTFU_S_EDGE ones only for non-UTF-8. */ |
| 1248 | |
| 1249 | if (STRING(n)[STR_LEN(n)-1] == 's') { |
| 1250 | |
| 1251 | /* Here the joined node would end with 's'. If the node |
| 1252 | * following the combination is an EXACTF one, it's better to |
| 1253 | * join this trailing edge 's' node with that one, leaving the |
| 1254 | * current one in 'scan' be the more desirable EXACTFU */ |
| 1255 | if (OP(nnext) == EXACTF) { |
| 1256 | break; |
| 1257 | } |
| 1258 | |
| 1259 | OP(scan) = EXACTFU_S_EDGE; |
| 1260 | |
| 1261 | } /* Otherwise, the beginning 's' of the 2nd node just |
| 1262 | becomes an interior 's' in 'scan' */ |
| 1263 | } |
| 1264 | else if (OP(scan) == EXACTF && OP(n) == EXACTF) { |
| 1265 | ; /* join is compatible, no need to change OP */ |
| 1266 | } |
| 1267 | else if (OP(scan) == EXACTF && OP(n) == EXACTFU_S_EDGE) { |
| 1268 | |
| 1269 | /* EXACTF nodes are compatible for joining with EXACTFU_S_EDGE |
| 1270 | * nodes. But the latter nodes can be also joined with EXACTFU |
| 1271 | * ones, and that is a better outcome, so if the node following |
| 1272 | * 'n' is EXACTFU, quit now so that those two can be joined |
| 1273 | * later */ |
| 1274 | if (OP(nnext) == EXACTFU) { |
| 1275 | break; |
| 1276 | } |
| 1277 | |
| 1278 | /* The join is compatible, and the combined node will be |
| 1279 | * EXACTF. (These don't care if they begin or end with 's' */ |
| 1280 | } |
| 1281 | else if (OP(scan) == EXACTFU_S_EDGE && OP(n) == EXACTFU_S_EDGE) { |
| 1282 | if ( STRING(scan)[STR_LEN(scan)-1] == 's' |
| 1283 | && STRING(n)[0] == 's') |
| 1284 | { |
| 1285 | /* When combined, we have the sequence 'ss', which means we |
| 1286 | * have to remain /di */ |
| 1287 | OP(scan) = EXACTF; |
| 1288 | } |
| 1289 | } |
| 1290 | else if (OP(scan) == EXACTFU_S_EDGE && OP(n) == EXACTFU) { |
| 1291 | if (STRING(n)[0] == 's') { |
| 1292 | ; /* Here the join is compatible and the combined node |
| 1293 | starts with 's', no need to change OP */ |
| 1294 | } |
| 1295 | else { /* Now the trailing 's' is in the interior */ |
| 1296 | OP(scan) = EXACTFU; |
| 1297 | } |
| 1298 | } |
| 1299 | else if (OP(scan) == EXACTFU_S_EDGE && OP(n) == EXACTF) { |
| 1300 | |
| 1301 | /* The join is compatible, and the combined node will be |
| 1302 | * EXACTF. (These don't care if they begin or end with 's' */ |
| 1303 | OP(scan) = EXACTF; |
| 1304 | } |
| 1305 | else if (OP(scan) != OP(n)) { |
| 1306 | |
| 1307 | /* The only other compatible joinings are the same node type */ |
| 1308 | break; |
| 1309 | } |
| 1310 | |
| 1311 | DEBUG_PEEP("merg", n, depth, 0); |
| 1312 | merged++; |
| 1313 | |
| 1314 | next = REGNODE_AFTER_varies(n); |
| 1315 | NEXT_OFF(scan) += NEXT_OFF(n); |
| 1316 | assert( ( STR_LEN(scan) + STR_LEN(n) ) < 256 ); |
| 1317 | setSTR_LEN(scan, (U8)(STR_LEN(scan) + STR_LEN(n))); |
| 1318 | /* Now we can overwrite *n : */ |
| 1319 | Move(STRING(n), STRING(scan) + oldl, STR_LEN(n), char); |
| 1320 | #ifdef DEBUGGING |
| 1321 | stop = next - 1; |
| 1322 | #endif |
| 1323 | n = nnext; |
| 1324 | if (stopnow) break; |
| 1325 | } |
| 1326 | |
| 1327 | #ifdef EXPERIMENTAL_INPLACESCAN |
| 1328 | if (flags && !NEXT_OFF(n)) { |
| 1329 | DEBUG_PEEP("atch", val, depth, 0); |
| 1330 | if (REGNODE_OFF_BY_ARG(OP(n))) { |
| 1331 | ARG_SET(n, val - n); |
| 1332 | } |
| 1333 | else { |
| 1334 | NEXT_OFF(n) = val - n; |
| 1335 | } |
| 1336 | stopnow = 1; |
| 1337 | } |
| 1338 | #endif |
| 1339 | } |
| 1340 | |
| 1341 | /* This temporary node can now be turned into EXACTFU, and must, as |
| 1342 | * regexec.c doesn't handle it */ |
| 1343 | if (OP(scan) == EXACTFU_S_EDGE) { |
| 1344 | OP(scan) = EXACTFU; |
| 1345 | } |
| 1346 | |
| 1347 | *min_subtract = 0; |
| 1348 | *unfolded_multi_char = FALSE; |
| 1349 | |
| 1350 | /* Here, all the adjacent mergeable EXACTish nodes have been merged. We |
| 1351 | * can now analyze for sequences of problematic code points. (Prior to |
| 1352 | * this final joining, sequences could have been split over boundaries, and |
| 1353 | * hence missed). The sequences only happen in folding, hence for any |
| 1354 | * non-EXACT EXACTish node */ |
| 1355 | if (OP(scan) != EXACT && OP(scan) != EXACT_REQ8 && OP(scan) != EXACTL) { |
| 1356 | U8* s0 = (U8*) STRING(scan); |
| 1357 | U8* s = s0; |
| 1358 | U8* s_end = s0 + STR_LEN(scan); |
| 1359 | |
| 1360 | int total_count_delta = 0; /* Total delta number of characters that |
| 1361 | multi-char folds expand to */ |
| 1362 | |
| 1363 | /* One pass is made over the node's string looking for all the |
| 1364 | * possibilities. To avoid some tests in the loop, there are two main |
| 1365 | * cases, for UTF-8 patterns (which can't have EXACTF nodes) and |
| 1366 | * non-UTF-8 */ |
| 1367 | if (UTF) { |
| 1368 | U8* folded = NULL; |
| 1369 | |
| 1370 | if (OP(scan) == EXACTFL) { |
| 1371 | U8 *d; |
| 1372 | |
| 1373 | /* An EXACTFL node would already have been changed to another |
| 1374 | * node type unless there is at least one character in it that |
| 1375 | * is problematic; likely a character whose fold definition |
| 1376 | * won't be known until runtime, and so has yet to be folded. |
| 1377 | * For all but the UTF-8 locale, folds are 1-1 in length, but |
| 1378 | * to handle the UTF-8 case, we need to create a temporary |
| 1379 | * folded copy using UTF-8 locale rules in order to analyze it. |
| 1380 | * This is because our macros that look to see if a sequence is |
| 1381 | * a multi-char fold assume everything is folded (otherwise the |
| 1382 | * tests in those macros would be too complicated and slow). |
| 1383 | * Note that here, the non-problematic folds will have already |
| 1384 | * been done, so we can just copy such characters. We actually |
| 1385 | * don't completely fold the EXACTFL string. We skip the |
| 1386 | * unfolded multi-char folds, as that would just create work |
| 1387 | * below to figure out the size they already are */ |
| 1388 | |
| 1389 | Newx(folded, UTF8_MAX_FOLD_CHAR_EXPAND * STR_LEN(scan) + 1, U8); |
| 1390 | d = folded; |
| 1391 | while (s < s_end) { |
| 1392 | STRLEN s_len = UTF8SKIP(s); |
| 1393 | if (! is_PROBLEMATIC_LOCALE_FOLD_utf8(s)) { |
| 1394 | Copy(s, d, s_len, U8); |
| 1395 | d += s_len; |
| 1396 | } |
| 1397 | else if (is_FOLDS_TO_MULTI_utf8(s)) { |
| 1398 | *unfolded_multi_char = TRUE; |
| 1399 | Copy(s, d, s_len, U8); |
| 1400 | d += s_len; |
| 1401 | } |
| 1402 | else if (isASCII(*s)) { |
| 1403 | *(d++) = toFOLD(*s); |
| 1404 | } |
| 1405 | else { |
| 1406 | STRLEN len; |
| 1407 | _toFOLD_utf8_flags(s, s_end, d, &len, FOLD_FLAGS_FULL); |
| 1408 | d += len; |
| 1409 | } |
| 1410 | s += s_len; |
| 1411 | } |
| 1412 | |
| 1413 | /* Point the remainder of the routine to look at our temporary |
| 1414 | * folded copy */ |
| 1415 | s = folded; |
| 1416 | s_end = d; |
| 1417 | } /* End of creating folded copy of EXACTFL string */ |
| 1418 | |
| 1419 | /* Examine the string for a multi-character fold sequence. UTF-8 |
| 1420 | * patterns have all characters pre-folded by the time this code is |
| 1421 | * executed */ |
| 1422 | while (s < s_end - 1) /* Can stop 1 before the end, as minimum |
| 1423 | length sequence we are looking for is 2 */ |
| 1424 | { |
| 1425 | int count = 0; /* How many characters in a multi-char fold */ |
| 1426 | int len = is_MULTI_CHAR_FOLD_utf8_safe(s, s_end); |
| 1427 | if (! len) { /* Not a multi-char fold: get next char */ |
| 1428 | s += UTF8SKIP(s); |
| 1429 | continue; |
| 1430 | } |
| 1431 | |
| 1432 | { /* Here is a generic multi-char fold. */ |
| 1433 | U8* multi_end = s + len; |
| 1434 | |
| 1435 | /* Count how many characters are in it. In the case of |
| 1436 | * /aa, no folds which contain ASCII code points are |
| 1437 | * allowed, so check for those, and skip if found. */ |
| 1438 | if (OP(scan) != EXACTFAA && OP(scan) != EXACTFAA_NO_TRIE) { |
| 1439 | count = utf8_length(s, multi_end); |
| 1440 | s = multi_end; |
| 1441 | } |
| 1442 | else { |
| 1443 | while (s < multi_end) { |
| 1444 | if (isASCII(*s)) { |
| 1445 | s++; |
| 1446 | goto next_iteration; |
| 1447 | } |
| 1448 | else { |
| 1449 | s += UTF8SKIP(s); |
| 1450 | } |
| 1451 | count++; |
| 1452 | } |
| 1453 | } |
| 1454 | } |
| 1455 | |
| 1456 | /* The delta is how long the sequence is minus 1 (1 is how long |
| 1457 | * the character that folds to the sequence is) */ |
| 1458 | total_count_delta += count - 1; |
| 1459 | next_iteration: ; |
| 1460 | } |
| 1461 | |
| 1462 | /* We created a temporary folded copy of the string in EXACTFL |
| 1463 | * nodes. Therefore we need to be sure it doesn't go below zero, |
| 1464 | * as the real string could be shorter */ |
| 1465 | if (OP(scan) == EXACTFL) { |
| 1466 | int total_chars = utf8_length((U8*) STRING(scan), |
| 1467 | (U8*) STRING(scan) + STR_LEN(scan)); |
| 1468 | if (total_count_delta > total_chars) { |
| 1469 | total_count_delta = total_chars; |
| 1470 | } |
| 1471 | } |
| 1472 | |
| 1473 | *min_subtract += total_count_delta; |
| 1474 | Safefree(folded); |
| 1475 | } |
| 1476 | else if (OP(scan) == EXACTFAA) { |
| 1477 | |
| 1478 | /* Non-UTF-8 pattern, EXACTFAA node. There can't be a multi-char |
| 1479 | * fold to the ASCII range (and there are no existing ones in the |
| 1480 | * upper latin1 range). But, as outlined in the comments preceding |
| 1481 | * this function, we need to flag any occurrences of the sharp s. |
| 1482 | * This character forbids trie formation (because of added |
| 1483 | * complexity) */ |
| 1484 | #if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \ |
| 1485 | || (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \ |
| 1486 | || UNICODE_DOT_DOT_VERSION > 0) |
| 1487 | while (s < s_end) { |
| 1488 | if (*s == LATIN_SMALL_LETTER_SHARP_S) { |
| 1489 | OP(scan) = EXACTFAA_NO_TRIE; |
| 1490 | *unfolded_multi_char = TRUE; |
| 1491 | break; |
| 1492 | } |
| 1493 | s++; |
| 1494 | } |
| 1495 | } |
| 1496 | else if (OP(scan) != EXACTFAA_NO_TRIE) { |
| 1497 | |
| 1498 | /* Non-UTF-8 pattern, not EXACTFAA node. Look for the multi-char |
| 1499 | * folds that are all Latin1. As explained in the comments |
| 1500 | * preceding this function, we look also for the sharp s in EXACTF |
| 1501 | * and EXACTFL nodes; it can be in the final position. Otherwise |
| 1502 | * we can stop looking 1 byte earlier because have to find at least |
| 1503 | * two characters for a multi-fold */ |
| 1504 | const U8* upper = (OP(scan) == EXACTF || OP(scan) == EXACTFL) |
| 1505 | ? s_end |
| 1506 | : s_end -1; |
| 1507 | |
| 1508 | while (s < upper) { |
| 1509 | int len = is_MULTI_CHAR_FOLD_latin1_safe(s, s_end); |
| 1510 | if (! len) { /* Not a multi-char fold. */ |
| 1511 | if (*s == LATIN_SMALL_LETTER_SHARP_S |
| 1512 | && (OP(scan) == EXACTF || OP(scan) == EXACTFL)) |
| 1513 | { |
| 1514 | *unfolded_multi_char = TRUE; |
| 1515 | } |
| 1516 | s++; |
| 1517 | continue; |
| 1518 | } |
| 1519 | |
| 1520 | if (len == 2 |
| 1521 | && isALPHA_FOLD_EQ(*s, 's') |
| 1522 | && isALPHA_FOLD_EQ(*(s+1), 's')) |
| 1523 | { |
| 1524 | |
| 1525 | /* EXACTF nodes need to know that the minimum length |
| 1526 | * changed so that a sharp s in the string can match this |
| 1527 | * ss in the pattern, but they remain EXACTF nodes, as they |
| 1528 | * won't match this unless the target string is in UTF-8, |
| 1529 | * which we don't know until runtime. EXACTFL nodes can't |
| 1530 | * transform into EXACTFU nodes */ |
| 1531 | if (OP(scan) != EXACTF && OP(scan) != EXACTFL) { |
| 1532 | OP(scan) = EXACTFUP; |
| 1533 | } |
| 1534 | } |
| 1535 | |
| 1536 | *min_subtract += len - 1; |
| 1537 | s += len; |
| 1538 | } |
| 1539 | #endif |
| 1540 | } |
| 1541 | } |
| 1542 | |
| 1543 | #ifdef DEBUGGING |
| 1544 | /* Allow dumping but overwriting the collection of skipped |
| 1545 | * ops and/or strings with fake optimized ops */ |
| 1546 | n = REGNODE_AFTER_varies(scan); |
| 1547 | while (n <= stop) { |
| 1548 | OP(n) = OPTIMIZED; |
| 1549 | FLAGS(n) = 0; |
| 1550 | NEXT_OFF(n) = 0; |
| 1551 | n++; |
| 1552 | } |
| 1553 | #endif |
| 1554 | DEBUG_OPTIMISE_r(if (merged){DEBUG_PEEP("finl", scan, depth, 0);}); |
| 1555 | return stopnow; |
| 1556 | } |
| 1557 | |
| 1558 | /* REx optimizer. Converts nodes into quicker variants "in place". |
| 1559 | Finds fixed substrings. */ |
| 1560 | |
| 1561 | |
| 1562 | /* Stops at toplevel WHILEM as well as at "last". At end *scanp is set |
| 1563 | to the position after last scanned or to NULL. */ |
| 1564 | |
| 1565 | /* the return from this sub is the minimum length that could possibly match */ |
| 1566 | SSize_t |
| 1567 | Perl_study_chunk(pTHX_ |
| 1568 | RExC_state_t *pRExC_state, |
| 1569 | regnode **scanp, /* Start here (read-write). */ |
| 1570 | SSize_t *minlenp, /* used for the minlen of substrings? */ |
| 1571 | SSize_t *deltap, /* Write maxlen-minlen here. */ |
| 1572 | regnode *last, /* Stop before this one. */ |
| 1573 | scan_data_t *data, /* string data about the pattern */ |
| 1574 | I32 stopparen, /* treat CLOSE-N as END, see GOSUB */ |
| 1575 | U32 recursed_depth, /* how deep have we recursed via GOSUB */ |
| 1576 | regnode_ssc *and_withp, /* Valid if flags & SCF_DO_STCLASS_OR */ |
| 1577 | U32 flags, /* flags controlling this call, see SCF_ flags */ |
| 1578 | U32 depth, /* how deep have we recursed period */ |
| 1579 | bool was_mutate_ok /* TRUE if in-place optimizations are allowed. |
| 1580 | FALSE only if the caller (recursively) was |
| 1581 | prohibited from modifying the regops, because |
| 1582 | a higher caller is holding a ptr to them. */ |
| 1583 | ) |
| 1584 | { |
| 1585 | /* vars about the regnodes we are working with */ |
| 1586 | regnode *scan = *scanp; /* the current opcode we are inspecting */ |
| 1587 | regnode *next = NULL; /* the next opcode beyond scan, tmp var */ |
| 1588 | regnode *first_non_open = scan; /* FIXME: should this init to NULL? |
| 1589 | the first non open regop, if the init |
| 1590 | val IS an OPEN then we will skip past |
| 1591 | it just after the var decls section */ |
| 1592 | I32 code = 0; /* temp var used to hold the optype of a regop */ |
| 1593 | |
| 1594 | /* vars about the min and max length of the pattern */ |
| 1595 | SSize_t min = 0; /* min length of this part of the pattern */ |
| 1596 | SSize_t stopmin = OPTIMIZE_INFTY; /* min length accounting for ACCEPT |
| 1597 | this is adjusted down if we find |
| 1598 | an ACCEPT */ |
| 1599 | SSize_t delta = 0; /* difference between min and max length |
| 1600 | (not accounting for stopmin) */ |
| 1601 | |
| 1602 | /* vars about capture buffers in the pattern */ |
| 1603 | I32 pars = 0; /* count of OPEN opcodes */ |
| 1604 | I32 is_par = OP(scan) == OPEN ? PARNO(scan) : 0; /* is this op an OPEN? */ |
| 1605 | |
| 1606 | /* vars about whether this pattern contains something that can match |
| 1607 | * infinitely long strings, eg, X* or X+ */ |
| 1608 | int is_inf = (flags & SCF_DO_SUBSTR) && (data->flags & SF_IS_INF); |
| 1609 | int is_inf_internal = 0; /* The studied chunk is infinite */ |
| 1610 | |
| 1611 | /* scan_data_t (struct) is used to hold information about the substrings |
| 1612 | * and start class we have extracted from the string */ |
| 1613 | scan_data_t data_fake; /* temp var used for recursing in some cases */ |
| 1614 | |
| 1615 | SV *re_trie_maxbuff = NULL; /* temp var used to hold whether we can do |
| 1616 | trie optimizations */ |
| 1617 | |
| 1618 | scan_frame *frame = NULL; /* used as part of fake recursion */ |
| 1619 | |
| 1620 | DECLARE_AND_GET_RE_DEBUG_FLAGS; |
| 1621 | |
| 1622 | PERL_ARGS_ASSERT_STUDY_CHUNK; |
| 1623 | RExC_study_started= 1; |
| 1624 | |
| 1625 | Zero(&data_fake, 1, scan_data_t); |
| 1626 | |
| 1627 | if ( depth == 0 ) { |
| 1628 | while (first_non_open && OP(first_non_open) == OPEN) |
| 1629 | first_non_open=regnext(first_non_open); |
| 1630 | } |
| 1631 | |
| 1632 | fake_study_recurse: |
| 1633 | DEBUG_r( |
| 1634 | RExC_study_chunk_recursed_count++; |
| 1635 | ); |
| 1636 | DEBUG_OPTIMISE_MORE_r( |
| 1637 | { |
| 1638 | Perl_re_indentf( aTHX_ "study_chunk stopparen=%ld recursed_count=%lu depth=%lu recursed_depth=%lu scan=%p last=%p", |
| 1639 | depth, (long)stopparen, |
| 1640 | (unsigned long)RExC_study_chunk_recursed_count, |
| 1641 | (unsigned long)depth, (unsigned long)recursed_depth, |
| 1642 | scan, |
| 1643 | last); |
| 1644 | if (recursed_depth) { |
| 1645 | U32 i; |
| 1646 | U32 j; |
| 1647 | for ( j = 0 ; j < recursed_depth ; j++ ) { |
| 1648 | for ( i = 0 ; i < (U32)RExC_total_parens ; i++ ) { |
| 1649 | if (PAREN_TEST(j, i) && (!j || !PAREN_TEST(j - 1, i))) { |
| 1650 | Perl_re_printf( aTHX_ " %d",(int)i); |
| 1651 | break; |
| 1652 | } |
| 1653 | } |
| 1654 | if ( j + 1 < recursed_depth ) { |
| 1655 | Perl_re_printf( aTHX_ ","); |
| 1656 | } |
| 1657 | } |
| 1658 | } |
| 1659 | Perl_re_printf( aTHX_ "\n"); |
| 1660 | } |
| 1661 | ); |
| 1662 | while ( scan && OP(scan) != END && scan < last ){ |
| 1663 | UV min_subtract = 0; /* How mmany chars to subtract from the minimum |
| 1664 | node length to get a real minimum (because |
| 1665 | the folded version may be shorter) */ |
| 1666 | bool unfolded_multi_char = FALSE; |
| 1667 | /* avoid mutating ops if we are anywhere within the recursed or |
| 1668 | * enframed handling for a GOSUB: the outermost level will handle it. |
| 1669 | */ |
| 1670 | bool mutate_ok = was_mutate_ok && !(frame && frame->in_gosub); |
| 1671 | /* Peephole optimizer: */ |
| 1672 | DEBUG_STUDYDATA("Peep", data, depth, is_inf, min, stopmin, delta); |
| 1673 | DEBUG_PEEP("Peep", scan, depth, flags); |
| 1674 | |
| 1675 | |
| 1676 | /* The reason we do this here is that we need to deal with things like |
| 1677 | * /(?:f)(?:o)(?:o)/ which cant be dealt with by the normal EXACT |
| 1678 | * parsing code, as each (?:..) is handled by a different invocation of |
| 1679 | * reg() -- Yves |
| 1680 | */ |
| 1681 | if (REGNODE_TYPE(OP(scan)) == EXACT |
| 1682 | && OP(scan) != LEXACT |
| 1683 | && OP(scan) != LEXACT_REQ8 |
| 1684 | && mutate_ok |
| 1685 | ) { |
| 1686 | join_exact(pRExC_state, scan, &min_subtract, &unfolded_multi_char, |
| 1687 | 0, NULL, depth + 1); |
| 1688 | } |
| 1689 | |
| 1690 | /* Follow the next-chain of the current node and optimize |
| 1691 | away all the NOTHINGs from it. |
| 1692 | */ |
| 1693 | rck_elide_nothing(scan); |
| 1694 | |
| 1695 | /* The principal pseudo-switch. Cannot be a switch, since we look into |
| 1696 | * several different things. */ |
| 1697 | if ( OP(scan) == DEFINEP ) { |
| 1698 | SSize_t minlen = 0; |
| 1699 | SSize_t deltanext = 0; |
| 1700 | SSize_t fake_last_close = 0; |
| 1701 | regnode *fake_last_close_op = NULL; |
| 1702 | U32 f = SCF_IN_DEFINE | (flags & SCF_TRIE_DOING_RESTUDY); |
| 1703 | |
| 1704 | StructCopy(&zero_scan_data, &data_fake, scan_data_t); |
| 1705 | scan = regnext(scan); |
| 1706 | assert( OP(scan) == IFTHEN ); |
| 1707 | DEBUG_PEEP("expect IFTHEN", scan, depth, flags); |
| 1708 | |
| 1709 | data_fake.last_closep= &fake_last_close; |
| 1710 | data_fake.last_close_opp= &fake_last_close_op; |
| 1711 | minlen = *minlenp; |
| 1712 | next = regnext(scan); |
| 1713 | scan = REGNODE_AFTER_type(scan,tregnode_IFTHEN); |
| 1714 | DEBUG_PEEP("scan", scan, depth, flags); |
| 1715 | DEBUG_PEEP("next", next, depth, flags); |
| 1716 | |
| 1717 | /* we suppose the run is continuous, last=next... |
| 1718 | * NOTE we dont use the return here! */ |
| 1719 | /* DEFINEP study_chunk() recursion */ |
| 1720 | (void)study_chunk(pRExC_state, &scan, &minlen, |
| 1721 | &deltanext, next, &data_fake, stopparen, |
| 1722 | recursed_depth, NULL, f, depth+1, mutate_ok); |
| 1723 | |
| 1724 | scan = next; |
| 1725 | } else |
| 1726 | if ( |
| 1727 | OP(scan) == BRANCH || |
| 1728 | OP(scan) == BRANCHJ || |
| 1729 | OP(scan) == IFTHEN |
| 1730 | ) { |
| 1731 | next = regnext(scan); |
| 1732 | code = OP(scan); |
| 1733 | |
| 1734 | /* The op(next)==code check below is to see if we |
| 1735 | * have "BRANCH-BRANCH", "BRANCHJ-BRANCHJ", "IFTHEN-IFTHEN" |
| 1736 | * IFTHEN is special as it might not appear in pairs. |
| 1737 | * Not sure whether BRANCH-BRANCHJ is possible, regardless |
| 1738 | * we dont handle it cleanly. */ |
| 1739 | if (OP(next) == code || code == IFTHEN) { |
| 1740 | /* NOTE - There is similar code to this block below for |
| 1741 | * handling TRIE nodes on a re-study. If you change stuff here |
| 1742 | * check there too. */ |
| 1743 | SSize_t max1 = 0, min1 = OPTIMIZE_INFTY, num = 0; |
| 1744 | regnode_ssc accum; |
| 1745 | regnode * const startbranch=scan; |
| 1746 | |
| 1747 | if (flags & SCF_DO_SUBSTR) { |
| 1748 | /* Cannot merge strings after this. */ |
| 1749 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 1750 | } |
| 1751 | |
| 1752 | if (flags & SCF_DO_STCLASS) |
| 1753 | ssc_init_zero(pRExC_state, &accum); |
| 1754 | |
| 1755 | while (OP(scan) == code) { |
| 1756 | SSize_t deltanext, minnext, fake_last_close = 0; |
| 1757 | regnode *fake_last_close_op = NULL; |
| 1758 | U32 f = (flags & SCF_TRIE_DOING_RESTUDY); |
| 1759 | regnode_ssc this_class; |
| 1760 | |
| 1761 | DEBUG_PEEP("Branch", scan, depth, flags); |
| 1762 | |
| 1763 | num++; |
| 1764 | StructCopy(&zero_scan_data, &data_fake, scan_data_t); |
| 1765 | if (data) { |
| 1766 | data_fake.whilem_c = data->whilem_c; |
| 1767 | data_fake.last_closep = data->last_closep; |
| 1768 | data_fake.last_close_opp = data->last_close_opp; |
| 1769 | } |
| 1770 | else { |
| 1771 | data_fake.last_closep = &fake_last_close; |
| 1772 | data_fake.last_close_opp = &fake_last_close_op; |
| 1773 | } |
| 1774 | |
| 1775 | data_fake.pos_delta = delta; |
| 1776 | next = regnext(scan); |
| 1777 | |
| 1778 | scan = REGNODE_AFTER_opcode(scan, code); |
| 1779 | |
| 1780 | if (flags & SCF_DO_STCLASS) { |
| 1781 | ssc_init(pRExC_state, &this_class); |
| 1782 | data_fake.start_class = &this_class; |
| 1783 | f |= SCF_DO_STCLASS_AND; |
| 1784 | } |
| 1785 | if (flags & SCF_WHILEM_VISITED_POS) |
| 1786 | f |= SCF_WHILEM_VISITED_POS; |
| 1787 | |
| 1788 | /* we suppose the run is continuous, last=next...*/ |
| 1789 | /* recurse study_chunk() for each BRANCH in an alternation */ |
| 1790 | minnext = study_chunk(pRExC_state, &scan, minlenp, |
| 1791 | &deltanext, next, &data_fake, stopparen, |
| 1792 | recursed_depth, NULL, f, depth+1, |
| 1793 | mutate_ok); |
| 1794 | |
| 1795 | if (min1 > minnext) |
| 1796 | min1 = minnext; |
| 1797 | if (deltanext == OPTIMIZE_INFTY) { |
| 1798 | is_inf = is_inf_internal = 1; |
| 1799 | max1 = OPTIMIZE_INFTY; |
| 1800 | } else if (max1 < minnext + deltanext) |
| 1801 | max1 = minnext + deltanext; |
| 1802 | scan = next; |
| 1803 | if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR)) |
| 1804 | pars++; |
| 1805 | if (data_fake.flags & SCF_SEEN_ACCEPT) { |
| 1806 | if ( stopmin > minnext) |
| 1807 | stopmin = min + min1; |
| 1808 | flags &= ~SCF_DO_SUBSTR; |
| 1809 | if (data) |
| 1810 | data->flags |= SCF_SEEN_ACCEPT; |
| 1811 | } |
| 1812 | if (data) { |
| 1813 | if (data_fake.flags & SF_HAS_EVAL) |
| 1814 | data->flags |= SF_HAS_EVAL; |
| 1815 | data->whilem_c = data_fake.whilem_c; |
| 1816 | } |
| 1817 | if (flags & SCF_DO_STCLASS) |
| 1818 | ssc_or(pRExC_state, &accum, (regnode_charclass*)&this_class); |
| 1819 | DEBUG_STUDYDATA("end BRANCH", data, depth, is_inf, min, stopmin, delta); |
| 1820 | } |
| 1821 | if (code == IFTHEN && num < 2) /* Empty ELSE branch */ |
| 1822 | min1 = 0; |
| 1823 | if (flags & SCF_DO_SUBSTR) { |
| 1824 | data->pos_min += min1; |
| 1825 | if (data->pos_delta >= OPTIMIZE_INFTY - (max1 - min1)) |
| 1826 | data->pos_delta = OPTIMIZE_INFTY; |
| 1827 | else |
| 1828 | data->pos_delta += max1 - min1; |
| 1829 | if (max1 != min1 || is_inf) |
| 1830 | data->cur_is_floating = 1; |
| 1831 | } |
| 1832 | min += min1; |
| 1833 | if (delta == OPTIMIZE_INFTY |
| 1834 | || OPTIMIZE_INFTY - delta - (max1 - min1) < 0) |
| 1835 | delta = OPTIMIZE_INFTY; |
| 1836 | else |
| 1837 | delta += max1 - min1; |
| 1838 | if (flags & SCF_DO_STCLASS_OR) { |
| 1839 | ssc_or(pRExC_state, data->start_class, (regnode_charclass*) &accum); |
| 1840 | if (min1) { |
| 1841 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 1842 | flags &= ~SCF_DO_STCLASS; |
| 1843 | } |
| 1844 | } |
| 1845 | else if (flags & SCF_DO_STCLASS_AND) { |
| 1846 | if (min1) { |
| 1847 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) &accum); |
| 1848 | flags &= ~SCF_DO_STCLASS; |
| 1849 | } |
| 1850 | else { |
| 1851 | /* Switch to OR mode: cache the old value of |
| 1852 | * data->start_class */ |
| 1853 | INIT_AND_WITHP; |
| 1854 | StructCopy(data->start_class, and_withp, regnode_ssc); |
| 1855 | flags &= ~SCF_DO_STCLASS_AND; |
| 1856 | StructCopy(&accum, data->start_class, regnode_ssc); |
| 1857 | flags |= SCF_DO_STCLASS_OR; |
| 1858 | } |
| 1859 | } |
| 1860 | DEBUG_STUDYDATA("pre TRIE", data, depth, is_inf, min, stopmin, delta); |
| 1861 | |
| 1862 | if (PERL_ENABLE_TRIE_OPTIMISATION |
| 1863 | && OP(startbranch) == BRANCH |
| 1864 | && mutate_ok |
| 1865 | ) { |
| 1866 | /* demq. |
| 1867 | |
| 1868 | Assuming this was/is a branch we are dealing with: 'scan' |
| 1869 | now points at the item that follows the branch sequence, |
| 1870 | whatever it is. We now start at the beginning of the |
| 1871 | sequence and look for subsequences of |
| 1872 | |
| 1873 | BRANCH->EXACT=>x1 |
| 1874 | BRANCH->EXACT=>x2 |
| 1875 | tail |
| 1876 | |
| 1877 | which would be constructed from a pattern like |
| 1878 | /A|LIST|OF|WORDS/ |
| 1879 | |
| 1880 | If we can find such a subsequence we need to turn the first |
| 1881 | element into a trie and then add the subsequent branch exact |
| 1882 | strings to the trie. |
| 1883 | |
| 1884 | We have two cases |
| 1885 | |
| 1886 | 1. patterns where the whole set of branches can be |
| 1887 | converted. |
| 1888 | |
| 1889 | 2. patterns where only a subset can be converted. |
| 1890 | |
| 1891 | In case 1 we can replace the whole set with a single regop |
| 1892 | for the trie. In case 2 we need to keep the start and end |
| 1893 | branches so |
| 1894 | |
| 1895 | 'BRANCH EXACT; BRANCH EXACT; BRANCH X' |
| 1896 | becomes BRANCH TRIE; BRANCH X; |
| 1897 | |
| 1898 | There is an additional case, that being where there is a |
| 1899 | common prefix, which gets split out into an EXACT like node |
| 1900 | preceding the TRIE node. |
| 1901 | |
| 1902 | If X(1..n)==tail then we can do a simple trie, if not we make |
| 1903 | a "jump" trie, such that when we match the appropriate word |
| 1904 | we "jump" to the appropriate tail node. Essentially we turn |
| 1905 | a nested if into a case structure of sorts. |
| 1906 | |
| 1907 | */ |
| 1908 | |
| 1909 | int made=0; |
| 1910 | if (!re_trie_maxbuff) { |
| 1911 | re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1); |
| 1912 | if (!SvIOK(re_trie_maxbuff)) |
| 1913 | sv_setiv(re_trie_maxbuff, RE_TRIE_MAXBUF_INIT); |
| 1914 | } |
| 1915 | if ( SvIV(re_trie_maxbuff)>=0 ) { |
| 1916 | regnode *cur; |
| 1917 | regnode *first = (regnode *)NULL; |
| 1918 | regnode *prev = (regnode *)NULL; |
| 1919 | regnode *tail = scan; |
| 1920 | U8 trietype = 0; |
| 1921 | U32 count=0; |
| 1922 | |
| 1923 | /* var tail is used because there may be a TAIL |
| 1924 | regop in the way. Ie, the exacts will point to the |
| 1925 | thing following the TAIL, but the last branch will |
| 1926 | point at the TAIL. So we advance tail. If we |
| 1927 | have nested (?:) we may have to move through several |
| 1928 | tails. |
| 1929 | */ |
| 1930 | |
| 1931 | while ( OP( tail ) == TAIL ) { |
| 1932 | /* this is the TAIL generated by (?:) */ |
| 1933 | tail = regnext( tail ); |
| 1934 | } |
| 1935 | |
| 1936 | |
| 1937 | DEBUG_TRIE_COMPILE_r({ |
| 1938 | regprop(RExC_rx, RExC_mysv, tail, NULL, pRExC_state); |
| 1939 | Perl_re_indentf( aTHX_ "%s %" UVuf ":%s\n", |
| 1940 | depth+1, |
| 1941 | "Looking for TRIE'able sequences. Tail node is ", |
| 1942 | (UV) REGNODE_OFFSET(tail), |
| 1943 | SvPV_nolen_const( RExC_mysv ) |
| 1944 | ); |
| 1945 | }); |
| 1946 | |
| 1947 | /* |
| 1948 | |
| 1949 | Step through the branches |
| 1950 | cur represents each branch, |
| 1951 | noper is the first thing to be matched as part |
| 1952 | of that branch |
| 1953 | noper_next is the regnext() of that node. |
| 1954 | |
| 1955 | We normally handle a case like this |
| 1956 | /FOO[xyz]|BAR[pqr]/ via a "jump trie" but we also |
| 1957 | support building with NOJUMPTRIE, which restricts |
| 1958 | the trie logic to structures like /FOO|BAR/. |
| 1959 | |
| 1960 | If noper is a trieable nodetype then the branch is |
| 1961 | a possible optimization target. If we are building |
| 1962 | under NOJUMPTRIE then we require that noper_next is |
| 1963 | the same as scan (our current position in the regex |
| 1964 | program). |
| 1965 | |
| 1966 | Once we have two or more consecutive such branches |
| 1967 | we can create a trie of the EXACT's contents and |
| 1968 | stitch it in place into the program. |
| 1969 | |
| 1970 | If the sequence represents all of the branches in |
| 1971 | the alternation we replace the entire thing with a |
| 1972 | single TRIE node. |
| 1973 | |
| 1974 | Otherwise when it is a subsequence we need to |
| 1975 | stitch it in place and replace only the relevant |
| 1976 | branches. This means the first branch has to remain |
| 1977 | as it is used by the alternation logic, and its |
| 1978 | next pointer, and needs to be repointed at the item |
| 1979 | on the branch chain following the last branch we |
| 1980 | have optimized away. |
| 1981 | |
| 1982 | This could be either a BRANCH, in which case the |
| 1983 | subsequence is internal, or it could be the item |
| 1984 | following the branch sequence in which case the |
| 1985 | subsequence is at the end (which does not |
| 1986 | necessarily mean the first node is the start of the |
| 1987 | alternation). |
| 1988 | |
| 1989 | TRIE_TYPE(X) is a define which maps the optype to a |
| 1990 | trietype. |
| 1991 | |
| 1992 | optype | trietype |
| 1993 | ----------------+----------- |
| 1994 | NOTHING | NOTHING |
| 1995 | EXACT | EXACT |
| 1996 | EXACT_REQ8 | EXACT |
| 1997 | EXACTFU | EXACTFU |
| 1998 | EXACTFU_REQ8 | EXACTFU |
| 1999 | EXACTFUP | EXACTFU |
| 2000 | EXACTFAA | EXACTFAA |
| 2001 | EXACTL | EXACTL |
| 2002 | EXACTFLU8 | EXACTFLU8 |
| 2003 | |
| 2004 | |
| 2005 | */ |
| 2006 | #define TRIE_TYPE(X) ( ( NOTHING == (X) ) \ |
| 2007 | ? NOTHING \ |
| 2008 | : ( EXACT == (X) || EXACT_REQ8 == (X) ) \ |
| 2009 | ? EXACT \ |
| 2010 | : ( EXACTFU == (X) \ |
| 2011 | || EXACTFU_REQ8 == (X) \ |
| 2012 | || EXACTFUP == (X) ) \ |
| 2013 | ? EXACTFU \ |
| 2014 | : ( EXACTFAA == (X) ) \ |
| 2015 | ? EXACTFAA \ |
| 2016 | : ( EXACTL == (X) ) \ |
| 2017 | ? EXACTL \ |
| 2018 | : ( EXACTFLU8 == (X) ) \ |
| 2019 | ? EXACTFLU8 \ |
| 2020 | : 0 ) |
| 2021 | |
| 2022 | /* dont use tail as the end marker for this traverse */ |
| 2023 | for ( cur = startbranch ; cur != scan ; cur = regnext( cur ) ) { |
| 2024 | regnode * const noper = REGNODE_AFTER( cur ); |
| 2025 | U8 noper_type = OP( noper ); |
| 2026 | U8 noper_trietype = TRIE_TYPE( noper_type ); |
| 2027 | #if defined(DEBUGGING) || defined(NOJUMPTRIE) |
| 2028 | regnode * const noper_next = regnext( noper ); |
| 2029 | U8 noper_next_type = (noper_next && noper_next < tail) ? OP(noper_next) : 0; |
| 2030 | U8 noper_next_trietype = (noper_next && noper_next < tail) ? TRIE_TYPE( noper_next_type ) :0; |
| 2031 | #endif |
| 2032 | |
| 2033 | DEBUG_TRIE_COMPILE_r({ |
| 2034 | regprop(RExC_rx, RExC_mysv, cur, NULL, pRExC_state); |
| 2035 | Perl_re_indentf( aTHX_ "- %d:%s (%d)", |
| 2036 | depth+1, |
| 2037 | REG_NODE_NUM(cur), SvPV_nolen_const( RExC_mysv ), REG_NODE_NUM(cur) ); |
| 2038 | |
| 2039 | regprop(RExC_rx, RExC_mysv, noper, NULL, pRExC_state); |
| 2040 | Perl_re_printf( aTHX_ " -> %d:%s", |
| 2041 | REG_NODE_NUM(noper), SvPV_nolen_const(RExC_mysv)); |
| 2042 | |
| 2043 | if ( noper_next ) { |
| 2044 | regprop(RExC_rx, RExC_mysv, noper_next, NULL, pRExC_state); |
| 2045 | Perl_re_printf( aTHX_ "\t=> %d:%s\t", |
| 2046 | REG_NODE_NUM(noper_next), SvPV_nolen_const(RExC_mysv)); |
| 2047 | } |
| 2048 | Perl_re_printf( aTHX_ "(First==%d,Last==%d,Cur==%d,tt==%s,ntt==%s,nntt==%s)\n", |
| 2049 | REG_NODE_NUM(first), REG_NODE_NUM(prev), REG_NODE_NUM(cur), |
| 2050 | REGNODE_NAME(trietype), REGNODE_NAME(noper_trietype), REGNODE_NAME(noper_next_trietype) |
| 2051 | ); |
| 2052 | }); |
| 2053 | |
| 2054 | /* Is noper a trieable nodetype that can be merged |
| 2055 | * with the current trie (if there is one)? */ |
| 2056 | if ( noper_trietype |
| 2057 | && |
| 2058 | ( |
| 2059 | ( noper_trietype == NOTHING ) |
| 2060 | || ( trietype == NOTHING ) |
| 2061 | || ( trietype == noper_trietype ) |
| 2062 | ) |
| 2063 | #ifdef NOJUMPTRIE |
| 2064 | && noper_next >= tail |
| 2065 | #endif |
| 2066 | && count < U16_MAX) |
| 2067 | { |
| 2068 | /* Handle mergable triable node Either we are |
| 2069 | * the first node in a new trieable sequence, |
| 2070 | * in which case we do some bookkeeping, |
| 2071 | * otherwise we update the end pointer. */ |
| 2072 | if ( !first ) { |
| 2073 | first = cur; |
| 2074 | if ( noper_trietype == NOTHING ) { |
| 2075 | #if !defined(DEBUGGING) && !defined(NOJUMPTRIE) |
| 2076 | regnode * const noper_next = regnext( noper ); |
| 2077 | U8 noper_next_type = (noper_next && noper_next < tail) ? OP(noper_next) : 0; |
| 2078 | U8 noper_next_trietype = noper_next_type ? TRIE_TYPE( noper_next_type ) :0; |
| 2079 | #endif |
| 2080 | |
| 2081 | if ( noper_next_trietype ) { |
| 2082 | trietype = noper_next_trietype; |
| 2083 | } else if (noper_next_type) { |
| 2084 | /* a NOTHING regop is 1 regop wide. |
| 2085 | * We need at least two for a trie |
| 2086 | * so we can't merge this in */ |
| 2087 | first = NULL; |
| 2088 | } |
| 2089 | } else { |
| 2090 | trietype = noper_trietype; |
| 2091 | } |
| 2092 | } else { |
| 2093 | if ( trietype == NOTHING ) |
| 2094 | trietype = noper_trietype; |
| 2095 | prev = cur; |
| 2096 | } |
| 2097 | if (first) |
| 2098 | count++; |
| 2099 | } /* end handle mergable triable node */ |
| 2100 | else { |
| 2101 | /* handle unmergable node - |
| 2102 | * noper may either be a triable node which can |
| 2103 | * not be tried together with the current trie, |
| 2104 | * or a non triable node */ |
| 2105 | if ( prev ) { |
| 2106 | /* If last is set and trietype is not |
| 2107 | * NOTHING then we have found at least two |
| 2108 | * triable branch sequences in a row of a |
| 2109 | * similar trietype so we can turn them |
| 2110 | * into a trie. If/when we allow NOTHING to |
| 2111 | * start a trie sequence this condition |
| 2112 | * will be required, and it isn't expensive |
| 2113 | * so we leave it in for now. */ |
| 2114 | if ( trietype && trietype != NOTHING ) |
| 2115 | make_trie( pRExC_state, |
| 2116 | startbranch, first, cur, tail, |
| 2117 | count, trietype, depth+1 ); |
| 2118 | prev = NULL; /* note: we clear/update |
| 2119 | first, trietype etc below, |
| 2120 | so we dont do it here */ |
| 2121 | } |
| 2122 | if ( noper_trietype |
| 2123 | #ifdef NOJUMPTRIE |
| 2124 | && noper_next >= tail |
| 2125 | #endif |
| 2126 | ){ |
| 2127 | /* noper is triable, so we can start a new |
| 2128 | * trie sequence */ |
| 2129 | count = 1; |
| 2130 | first = cur; |
| 2131 | trietype = noper_trietype; |
| 2132 | } else if (first) { |
| 2133 | /* if we already saw a first but the |
| 2134 | * current node is not triable then we have |
| 2135 | * to reset the first information. */ |
| 2136 | count = 0; |
| 2137 | first = NULL; |
| 2138 | trietype = 0; |
| 2139 | } |
| 2140 | } /* end handle unmergable node */ |
| 2141 | } /* loop over branches */ |
| 2142 | DEBUG_TRIE_COMPILE_r({ |
| 2143 | regprop(RExC_rx, RExC_mysv, cur, NULL, pRExC_state); |
| 2144 | Perl_re_indentf( aTHX_ "- %s (%d) <SCAN FINISHED> ", |
| 2145 | depth+1, SvPV_nolen_const( RExC_mysv ), REG_NODE_NUM(cur)); |
| 2146 | Perl_re_printf( aTHX_ "(First==%d, Last==%d, Cur==%d, tt==%s)\n", |
| 2147 | REG_NODE_NUM(first), REG_NODE_NUM(prev), REG_NODE_NUM(cur), |
| 2148 | REGNODE_NAME(trietype) |
| 2149 | ); |
| 2150 | |
| 2151 | }); |
| 2152 | if ( prev && trietype ) { |
| 2153 | if ( trietype != NOTHING ) { |
| 2154 | /* the last branch of the sequence was part of |
| 2155 | * a trie, so we have to construct it here |
| 2156 | * outside of the loop */ |
| 2157 | made= make_trie( pRExC_state, startbranch, |
| 2158 | first, scan, tail, count, |
| 2159 | trietype, depth+1 ); |
| 2160 | #ifdef TRIE_STUDY_OPT |
| 2161 | if ( ((made == MADE_EXACT_TRIE && |
| 2162 | startbranch == first) |
| 2163 | || ( first_non_open == first )) && |
| 2164 | depth==0 ) { |
| 2165 | flags |= SCF_TRIE_RESTUDY; |
| 2166 | if ( startbranch == first |
| 2167 | && scan >= tail ) |
| 2168 | { |
| 2169 | RExC_seen &=~REG_TOP_LEVEL_BRANCHES_SEEN; |
| 2170 | } |
| 2171 | } |
| 2172 | #endif |
| 2173 | } else { |
| 2174 | /* at this point we know whatever we have is a |
| 2175 | * NOTHING sequence/branch AND if 'startbranch' |
| 2176 | * is 'first' then we can turn the whole thing |
| 2177 | * into a NOTHING |
| 2178 | */ |
| 2179 | if ( startbranch == first ) { |
| 2180 | regnode *opt; |
| 2181 | /* the entire thing is a NOTHING sequence, |
| 2182 | * something like this: (?:|) So we can |
| 2183 | * turn it into a plain NOTHING op. */ |
| 2184 | DEBUG_TRIE_COMPILE_r({ |
| 2185 | regprop(RExC_rx, RExC_mysv, cur, NULL, pRExC_state); |
| 2186 | Perl_re_indentf( aTHX_ "- %s (%d) <NOTHING BRANCH SEQUENCE>\n", |
| 2187 | depth+1, |
| 2188 | SvPV_nolen_const( RExC_mysv ), REG_NODE_NUM(cur)); |
| 2189 | |
| 2190 | }); |
| 2191 | OP(startbranch)= NOTHING; |
| 2192 | NEXT_OFF(startbranch)= tail - startbranch; |
| 2193 | for ( opt= startbranch + 1; opt < tail ; opt++ ) |
| 2194 | OP(opt)= OPTIMIZED; |
| 2195 | } |
| 2196 | } |
| 2197 | } /* end if ( prev) */ |
| 2198 | } /* TRIE_MAXBUF is non zero */ |
| 2199 | } /* do trie */ |
| 2200 | DEBUG_STUDYDATA("after TRIE", data, depth, is_inf, min, stopmin, delta); |
| 2201 | } |
| 2202 | else |
| 2203 | scan = REGNODE_AFTER_opcode(scan,code); |
| 2204 | continue; |
| 2205 | } else if (OP(scan) == SUSPEND || OP(scan) == GOSUB) { |
| 2206 | I32 paren = 0; |
| 2207 | regnode *start = NULL; |
| 2208 | regnode *end = NULL; |
| 2209 | U32 my_recursed_depth= recursed_depth; |
| 2210 | |
| 2211 | if (OP(scan) != SUSPEND) { /* GOSUB */ |
| 2212 | /* Do setup, note this code has side effects beyond |
| 2213 | * the rest of this block. Specifically setting |
| 2214 | * RExC_recurse[] must happen at least once during |
| 2215 | * study_chunk(). */ |
| 2216 | paren = ARG(scan); |
| 2217 | RExC_recurse[ARG2L(scan)] = scan; |
| 2218 | start = REGNODE_p(RExC_open_parens[paren]); |
| 2219 | end = REGNODE_p(RExC_close_parens[paren]); |
| 2220 | |
| 2221 | /* NOTE we MUST always execute the above code, even |
| 2222 | * if we do nothing with a GOSUB */ |
| 2223 | if ( |
| 2224 | ( flags & SCF_IN_DEFINE ) |
| 2225 | || |
| 2226 | ( |
| 2227 | (is_inf_internal || is_inf || (data && data->flags & SF_IS_INF)) |
| 2228 | && |
| 2229 | ( (flags & (SCF_DO_STCLASS | SCF_DO_SUBSTR)) == 0 ) |
| 2230 | ) |
| 2231 | ) { |
| 2232 | /* no need to do anything here if we are in a define. */ |
| 2233 | /* or we are after some kind of infinite construct |
| 2234 | * so we can skip recursing into this item. |
| 2235 | * Since it is infinite we will not change the maxlen |
| 2236 | * or delta, and if we miss something that might raise |
| 2237 | * the minlen it will merely pessimise a little. |
| 2238 | * |
| 2239 | * Iow /(?(DEFINE)(?<foo>foo|food))a+(?&foo)/ |
| 2240 | * might result in a minlen of 1 and not of 4, |
| 2241 | * but this doesn't make us mismatch, just try a bit |
| 2242 | * harder than we should. |
| 2243 | * |
| 2244 | * However we must assume this GOSUB is infinite, to |
| 2245 | * avoid wrongly applying other optimizations in the |
| 2246 | * enclosing scope - see GH 18096, for example. |
| 2247 | */ |
| 2248 | is_inf = is_inf_internal = 1; |
| 2249 | scan= regnext(scan); |
| 2250 | continue; |
| 2251 | } |
| 2252 | |
| 2253 | if ( |
| 2254 | !recursed_depth |
| 2255 | || !PAREN_TEST(recursed_depth - 1, paren) |
| 2256 | ) { |
| 2257 | /* it is quite possible that there are more efficient ways |
| 2258 | * to do this. We maintain a bitmap per level of recursion |
| 2259 | * of which patterns we have entered so we can detect if a |
| 2260 | * pattern creates a possible infinite loop. When we |
| 2261 | * recurse down a level we copy the previous levels bitmap |
| 2262 | * down. When we are at recursion level 0 we zero the top |
| 2263 | * level bitmap. It would be nice to implement a different |
| 2264 | * more efficient way of doing this. In particular the top |
| 2265 | * level bitmap may be unnecessary. |
| 2266 | */ |
| 2267 | if (!recursed_depth) { |
| 2268 | Zero(RExC_study_chunk_recursed, RExC_study_chunk_recursed_bytes, U8); |
| 2269 | } else { |
| 2270 | Copy(PAREN_OFFSET(recursed_depth - 1), |
| 2271 | PAREN_OFFSET(recursed_depth), |
| 2272 | RExC_study_chunk_recursed_bytes, U8); |
| 2273 | } |
| 2274 | /* we havent recursed into this paren yet, so recurse into it */ |
| 2275 | DEBUG_STUDYDATA("gosub-set", data, depth, is_inf, min, stopmin, delta); |
| 2276 | PAREN_SET(recursed_depth, paren); |
| 2277 | my_recursed_depth= recursed_depth + 1; |
| 2278 | } else { |
| 2279 | DEBUG_STUDYDATA("gosub-inf", data, depth, is_inf, min, stopmin, delta); |
| 2280 | /* some form of infinite recursion, assume infinite length |
| 2281 | * */ |
| 2282 | if (flags & SCF_DO_SUBSTR) { |
| 2283 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2284 | data->cur_is_floating = 1; |
| 2285 | } |
| 2286 | is_inf = is_inf_internal = 1; |
| 2287 | if (flags & SCF_DO_STCLASS_OR) /* Allow everything */ |
| 2288 | ssc_anything(data->start_class); |
| 2289 | flags &= ~SCF_DO_STCLASS; |
| 2290 | |
| 2291 | start= NULL; /* reset start so we dont recurse later on. */ |
| 2292 | } |
| 2293 | } else { |
| 2294 | paren = stopparen; |
| 2295 | start = scan + 2; |
| 2296 | end = regnext(scan); |
| 2297 | } |
| 2298 | if (start) { |
| 2299 | scan_frame *newframe; |
| 2300 | assert(end); |
| 2301 | if (!RExC_frame_last) { |
| 2302 | Newxz(newframe, 1, scan_frame); |
| 2303 | SAVEDESTRUCTOR_X(S_unwind_scan_frames, newframe); |
| 2304 | RExC_frame_head= newframe; |
| 2305 | RExC_frame_count++; |
| 2306 | } else if (!RExC_frame_last->next_frame) { |
| 2307 | Newxz(newframe, 1, scan_frame); |
| 2308 | RExC_frame_last->next_frame= newframe; |
| 2309 | newframe->prev_frame= RExC_frame_last; |
| 2310 | RExC_frame_count++; |
| 2311 | } else { |
| 2312 | newframe= RExC_frame_last->next_frame; |
| 2313 | } |
| 2314 | RExC_frame_last= newframe; |
| 2315 | |
| 2316 | newframe->next_regnode = regnext(scan); |
| 2317 | newframe->last_regnode = last; |
| 2318 | newframe->stopparen = stopparen; |
| 2319 | newframe->prev_recursed_depth = recursed_depth; |
| 2320 | newframe->this_prev_frame= frame; |
| 2321 | newframe->in_gosub = ( |
| 2322 | (frame && frame->in_gosub) || OP(scan) == GOSUB |
| 2323 | ); |
| 2324 | |
| 2325 | DEBUG_STUDYDATA("frame-new", data, depth, is_inf, min, stopmin, delta); |
| 2326 | DEBUG_PEEP("fnew", scan, depth, flags); |
| 2327 | |
| 2328 | frame = newframe; |
| 2329 | scan = start; |
| 2330 | stopparen = paren; |
| 2331 | last = end; |
| 2332 | depth = depth + 1; |
| 2333 | recursed_depth= my_recursed_depth; |
| 2334 | |
| 2335 | continue; |
| 2336 | } |
| 2337 | } |
| 2338 | else if (REGNODE_TYPE(OP(scan)) == EXACT && ! isEXACTFish(OP(scan))) { |
| 2339 | SSize_t bytelen = STR_LEN(scan), charlen; |
| 2340 | UV uc; |
| 2341 | assert(bytelen); |
| 2342 | if (UTF) { |
| 2343 | const U8 * const s = (U8*)STRING(scan); |
| 2344 | uc = utf8_to_uvchr_buf(s, s + bytelen, NULL); |
| 2345 | charlen = utf8_length(s, s + bytelen); |
| 2346 | } else { |
| 2347 | uc = *((U8*)STRING(scan)); |
| 2348 | charlen = bytelen; |
| 2349 | } |
| 2350 | min += charlen; |
| 2351 | if (flags & SCF_DO_SUBSTR) { /* Update longest substr. */ |
| 2352 | /* The code below prefers earlier match for fixed |
| 2353 | offset, later match for variable offset. */ |
| 2354 | if (data->last_end == -1) { /* Update the start info. */ |
| 2355 | data->last_start_min = data->pos_min; |
| 2356 | data->last_start_max = |
| 2357 | is_inf ? OPTIMIZE_INFTY |
| 2358 | : (data->pos_delta > OPTIMIZE_INFTY - data->pos_min) |
| 2359 | ? OPTIMIZE_INFTY : data->pos_min + data->pos_delta; |
| 2360 | } |
| 2361 | sv_catpvn(data->last_found, STRING(scan), bytelen); |
| 2362 | if (UTF) |
| 2363 | SvUTF8_on(data->last_found); |
| 2364 | { |
| 2365 | SV * const sv = data->last_found; |
| 2366 | MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ? |
| 2367 | mg_find(sv, PERL_MAGIC_utf8) : NULL; |
| 2368 | if (mg && mg->mg_len >= 0) |
| 2369 | mg->mg_len += charlen; |
| 2370 | } |
| 2371 | data->last_end = data->pos_min + charlen; |
| 2372 | data->pos_min += charlen; /* As in the first entry. */ |
| 2373 | data->flags &= ~SF_BEFORE_EOL; |
| 2374 | } |
| 2375 | |
| 2376 | /* ANDing the code point leaves at most it, and not in locale, and |
| 2377 | * can't match null string */ |
| 2378 | if (flags & SCF_DO_STCLASS_AND) { |
| 2379 | ssc_cp_and(data->start_class, uc); |
| 2380 | ANYOF_FLAGS(data->start_class) &= ~SSC_MATCHES_EMPTY_STRING; |
| 2381 | ssc_clear_locale(data->start_class); |
| 2382 | } |
| 2383 | else if (flags & SCF_DO_STCLASS_OR) { |
| 2384 | ssc_add_cp(data->start_class, uc); |
| 2385 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 2386 | |
| 2387 | /* See commit msg 749e076fceedeb708a624933726e7989f2302f6a */ |
| 2388 | ANYOF_FLAGS(data->start_class) &= ~SSC_MATCHES_EMPTY_STRING; |
| 2389 | } |
| 2390 | flags &= ~SCF_DO_STCLASS; |
| 2391 | DEBUG_STUDYDATA("end EXACT", data, depth, is_inf, min, stopmin, delta); |
| 2392 | } |
| 2393 | else if (REGNODE_TYPE(OP(scan)) == EXACT) { |
| 2394 | /* But OP != EXACT!, so is EXACTFish */ |
| 2395 | SSize_t bytelen = STR_LEN(scan), charlen; |
| 2396 | const U8 * s = (U8*)STRING(scan); |
| 2397 | |
| 2398 | /* Replace a length 1 ASCII fold pair node with an ANYOFM node, |
| 2399 | * with the mask set to the complement of the bit that differs |
| 2400 | * between upper and lower case, and the lowest code point of the |
| 2401 | * pair (which the '&' forces) */ |
| 2402 | if ( bytelen == 1 |
| 2403 | && isALPHA_A(*s) |
| 2404 | && ( OP(scan) == EXACTFAA |
| 2405 | || ( OP(scan) == EXACTFU |
| 2406 | && ! HAS_NONLATIN1_SIMPLE_FOLD_CLOSURE(*s))) |
| 2407 | && mutate_ok |
| 2408 | ) { |
| 2409 | U8 mask = ~ ('A' ^ 'a'); /* These differ in just one bit */ |
| 2410 | |
| 2411 | OP(scan) = ANYOFM; |
| 2412 | ARG_SET(scan, *s & mask); |
| 2413 | FLAGS(scan) = mask; |
| 2414 | /* We're not EXACTFish any more, so restudy. |
| 2415 | * Search for "restudy" in this file to find |
| 2416 | * a comment with details. */ |
| 2417 | continue; |
| 2418 | } |
| 2419 | |
| 2420 | /* Search for fixed substrings supports EXACT only. */ |
| 2421 | if (flags & SCF_DO_SUBSTR) { |
| 2422 | assert(data); |
| 2423 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2424 | } |
| 2425 | charlen = UTF ? (SSize_t) utf8_length(s, s + bytelen) : bytelen; |
| 2426 | if (unfolded_multi_char) { |
| 2427 | RExC_seen |= REG_UNFOLDED_MULTI_SEEN; |
| 2428 | } |
| 2429 | min += charlen - min_subtract; |
| 2430 | assert (min >= 0); |
| 2431 | if ((SSize_t)min_subtract < OPTIMIZE_INFTY |
| 2432 | && delta < OPTIMIZE_INFTY - (SSize_t)min_subtract |
| 2433 | ) { |
| 2434 | delta += min_subtract; |
| 2435 | } else { |
| 2436 | delta = OPTIMIZE_INFTY; |
| 2437 | } |
| 2438 | if (flags & SCF_DO_SUBSTR) { |
| 2439 | data->pos_min += charlen - min_subtract; |
| 2440 | if (data->pos_min < 0) { |
| 2441 | data->pos_min = 0; |
| 2442 | } |
| 2443 | if ((SSize_t)min_subtract < OPTIMIZE_INFTY |
| 2444 | && data->pos_delta < OPTIMIZE_INFTY - (SSize_t)min_subtract |
| 2445 | ) { |
| 2446 | data->pos_delta += min_subtract; |
| 2447 | } else { |
| 2448 | data->pos_delta = OPTIMIZE_INFTY; |
| 2449 | } |
| 2450 | if (min_subtract) { |
| 2451 | data->cur_is_floating = 1; /* float */ |
| 2452 | } |
| 2453 | } |
| 2454 | |
| 2455 | if (flags & SCF_DO_STCLASS) { |
| 2456 | SV* EXACTF_invlist = make_exactf_invlist(pRExC_state, scan); |
| 2457 | |
| 2458 | assert(EXACTF_invlist); |
| 2459 | if (flags & SCF_DO_STCLASS_AND) { |
| 2460 | if (OP(scan) != EXACTFL) |
| 2461 | ssc_clear_locale(data->start_class); |
| 2462 | ANYOF_FLAGS(data->start_class) &= ~SSC_MATCHES_EMPTY_STRING; |
| 2463 | ANYOF_POSIXL_ZERO(data->start_class); |
| 2464 | ssc_intersection(data->start_class, EXACTF_invlist, FALSE); |
| 2465 | } |
| 2466 | else { /* SCF_DO_STCLASS_OR */ |
| 2467 | ssc_union(data->start_class, EXACTF_invlist, FALSE); |
| 2468 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 2469 | |
| 2470 | /* See commit msg 749e076fceedeb708a624933726e7989f2302f6a */ |
| 2471 | ANYOF_FLAGS(data->start_class) &= ~SSC_MATCHES_EMPTY_STRING; |
| 2472 | } |
| 2473 | flags &= ~SCF_DO_STCLASS; |
| 2474 | SvREFCNT_dec(EXACTF_invlist); |
| 2475 | } |
| 2476 | DEBUG_STUDYDATA("end EXACTish", data, depth, is_inf, min, stopmin, delta); |
| 2477 | } |
| 2478 | else if (REGNODE_VARIES(OP(scan))) { |
| 2479 | SSize_t mincount, maxcount, minnext, deltanext, pos_before = 0; |
| 2480 | I32 fl = 0; |
| 2481 | U32 f = flags; |
| 2482 | regnode * const oscan = scan; |
| 2483 | regnode_ssc this_class; |
| 2484 | regnode_ssc *oclass = NULL; |
| 2485 | I32 next_is_eval = 0; |
| 2486 | |
| 2487 | switch (REGNODE_TYPE(OP(scan))) { |
| 2488 | case WHILEM: /* End of (?:...)* . */ |
| 2489 | scan = REGNODE_AFTER(scan); |
| 2490 | goto finish; |
| 2491 | case PLUS: |
| 2492 | if (flags & (SCF_DO_SUBSTR | SCF_DO_STCLASS)) { |
| 2493 | next = REGNODE_AFTER(scan); |
| 2494 | if ( ( REGNODE_TYPE(OP(next)) == EXACT |
| 2495 | && ! isEXACTFish(OP(next))) |
| 2496 | || (flags & SCF_DO_STCLASS)) |
| 2497 | { |
| 2498 | mincount = 1; |
| 2499 | maxcount = REG_INFTY; |
| 2500 | next = regnext(scan); |
| 2501 | scan = REGNODE_AFTER(scan); |
| 2502 | goto do_curly; |
| 2503 | } |
| 2504 | } |
| 2505 | if (flags & SCF_DO_SUBSTR) |
| 2506 | data->pos_min++; |
| 2507 | /* This will bypass the formal 'min += minnext * mincount' |
| 2508 | * calculation in the do_curly path, so assumes min width |
| 2509 | * of the PLUS payload is exactly one. */ |
| 2510 | min++; |
| 2511 | /* FALLTHROUGH */ |
| 2512 | case STAR: |
| 2513 | next = REGNODE_AFTER(scan); |
| 2514 | |
| 2515 | /* This temporary node can now be turned into EXACTFU, and |
| 2516 | * must, as regexec.c doesn't handle it */ |
| 2517 | if (OP(next) == EXACTFU_S_EDGE && mutate_ok) { |
| 2518 | OP(next) = EXACTFU; |
| 2519 | } |
| 2520 | |
| 2521 | if ( STR_LEN(next) == 1 |
| 2522 | && isALPHA_A(* STRING(next)) |
| 2523 | && ( OP(next) == EXACTFAA |
| 2524 | || ( OP(next) == EXACTFU |
| 2525 | && ! HAS_NONLATIN1_SIMPLE_FOLD_CLOSURE(* STRING(next)))) |
| 2526 | && mutate_ok |
| 2527 | ) { |
| 2528 | /* These differ in just one bit */ |
| 2529 | U8 mask = ~ ('A' ^ 'a'); |
| 2530 | |
| 2531 | assert(isALPHA_A(* STRING(next))); |
| 2532 | |
| 2533 | /* Then replace it by an ANYOFM node, with |
| 2534 | * the mask set to the complement of the |
| 2535 | * bit that differs between upper and lower |
| 2536 | * case, and the lowest code point of the |
| 2537 | * pair (which the '&' forces) */ |
| 2538 | OP(next) = ANYOFM; |
| 2539 | ARG_SET(next, *STRING(next) & mask); |
| 2540 | FLAGS(next) = mask; |
| 2541 | } |
| 2542 | |
| 2543 | if (flags & SCF_DO_STCLASS) { |
| 2544 | mincount = 0; |
| 2545 | maxcount = REG_INFTY; |
| 2546 | next = regnext(scan); |
| 2547 | scan = REGNODE_AFTER(scan); |
| 2548 | goto do_curly; |
| 2549 | } |
| 2550 | if (flags & SCF_DO_SUBSTR) { |
| 2551 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2552 | /* Cannot extend fixed substrings */ |
| 2553 | data->cur_is_floating = 1; /* float */ |
| 2554 | } |
| 2555 | is_inf = is_inf_internal = 1; |
| 2556 | scan = regnext(scan); |
| 2557 | goto optimize_curly_tail; |
| 2558 | case CURLY: |
| 2559 | if (stopparen>0 && (OP(scan)==CURLYN || OP(scan)==CURLYM) |
| 2560 | && (scan->flags == stopparen)) |
| 2561 | { |
| 2562 | mincount = 1; |
| 2563 | maxcount = 1; |
| 2564 | } else { |
| 2565 | mincount = ARG1(scan); |
| 2566 | maxcount = ARG2(scan); |
| 2567 | } |
| 2568 | next = regnext(scan); |
| 2569 | if (OP(scan) == CURLYX) { |
| 2570 | I32 lp = (data ? *(data->last_closep) : 0); |
| 2571 | scan->flags = ((lp <= (I32)U8_MAX) ? (U8)lp : U8_MAX); |
| 2572 | } |
| 2573 | scan = REGNODE_AFTER(scan); |
| 2574 | next_is_eval = (OP(scan) == EVAL); |
| 2575 | do_curly: |
| 2576 | if (flags & SCF_DO_SUBSTR) { |
| 2577 | if (mincount == 0) |
| 2578 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2579 | /* Cannot extend fixed substrings */ |
| 2580 | pos_before = data->pos_min; |
| 2581 | } |
| 2582 | if (data) { |
| 2583 | fl = data->flags; |
| 2584 | data->flags &= ~(SF_HAS_PAR|SF_IN_PAR|SF_HAS_EVAL); |
| 2585 | if (is_inf) |
| 2586 | data->flags |= SF_IS_INF; |
| 2587 | } |
| 2588 | if (flags & SCF_DO_STCLASS) { |
| 2589 | ssc_init(pRExC_state, &this_class); |
| 2590 | oclass = data->start_class; |
| 2591 | data->start_class = &this_class; |
| 2592 | f |= SCF_DO_STCLASS_AND; |
| 2593 | f &= ~SCF_DO_STCLASS_OR; |
| 2594 | } |
| 2595 | /* Exclude from super-linear cache processing any {n,m} |
| 2596 | regops for which the combination of input pos and regex |
| 2597 | pos is not enough information to determine if a match |
| 2598 | will be possible. |
| 2599 | |
| 2600 | For example, in the regex /foo(bar\s*){4,8}baz/ with the |
| 2601 | regex pos at the \s*, the prospects for a match depend not |
| 2602 | only on the input position but also on how many (bar\s*) |
| 2603 | repeats into the {4,8} we are. */ |
| 2604 | if ((mincount > 1) || (maxcount > 1 && maxcount != REG_INFTY)) |
| 2605 | f &= ~SCF_WHILEM_VISITED_POS; |
| 2606 | |
| 2607 | /* This will finish on WHILEM, setting scan, or on NULL: */ |
| 2608 | /* recurse study_chunk() on loop bodies */ |
| 2609 | minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext, |
| 2610 | last, data, stopparen, recursed_depth, NULL, |
| 2611 | (mincount == 0 |
| 2612 | ? (f & ~SCF_DO_SUBSTR) |
| 2613 | : f) |
| 2614 | , depth+1, mutate_ok); |
| 2615 | |
| 2616 | if (data && data->flags & SCF_SEEN_ACCEPT) { |
| 2617 | if (mincount > 1) |
| 2618 | mincount = 1; |
| 2619 | } |
| 2620 | |
| 2621 | if (flags & SCF_DO_STCLASS) |
| 2622 | data->start_class = oclass; |
| 2623 | if (mincount == 0 || minnext == 0) { |
| 2624 | if (flags & SCF_DO_STCLASS_OR) { |
| 2625 | ssc_or(pRExC_state, data->start_class, (regnode_charclass *) &this_class); |
| 2626 | } |
| 2627 | else if (flags & SCF_DO_STCLASS_AND) { |
| 2628 | /* Switch to OR mode: cache the old value of |
| 2629 | * data->start_class */ |
| 2630 | INIT_AND_WITHP; |
| 2631 | StructCopy(data->start_class, and_withp, regnode_ssc); |
| 2632 | flags &= ~SCF_DO_STCLASS_AND; |
| 2633 | StructCopy(&this_class, data->start_class, regnode_ssc); |
| 2634 | flags |= SCF_DO_STCLASS_OR; |
| 2635 | ANYOF_FLAGS(data->start_class) |
| 2636 | |= SSC_MATCHES_EMPTY_STRING; |
| 2637 | } |
| 2638 | } else { /* Non-zero len */ |
| 2639 | if (flags & SCF_DO_STCLASS_OR) { |
| 2640 | ssc_or(pRExC_state, data->start_class, (regnode_charclass *) &this_class); |
| 2641 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 2642 | } |
| 2643 | else if (flags & SCF_DO_STCLASS_AND) |
| 2644 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) &this_class); |
| 2645 | flags &= ~SCF_DO_STCLASS; |
| 2646 | } |
| 2647 | if (!scan) /* It was not CURLYX, but CURLY. */ |
| 2648 | scan = next; |
| 2649 | if (((flags & (SCF_TRIE_DOING_RESTUDY|SCF_DO_SUBSTR))==SCF_DO_SUBSTR) |
| 2650 | /* ? quantifier ok, except for (?{ ... }) */ |
| 2651 | && (next_is_eval || !(mincount == 0 && maxcount == 1)) |
| 2652 | && (minnext == 0) && (deltanext == 0) |
| 2653 | && data && !(data->flags & (SF_HAS_PAR|SF_IN_PAR)) |
| 2654 | && maxcount <= REG_INFTY/3) /* Complement check for big |
| 2655 | count */ |
| 2656 | { |
| 2657 | _WARN_HELPER(RExC_precomp_end, packWARN(WARN_REGEXP), |
| 2658 | Perl_ck_warner(aTHX_ packWARN(WARN_REGEXP), |
| 2659 | "Quantifier unexpected on zero-length expression " |
| 2660 | "in regex m/%" UTF8f "/", |
| 2661 | UTF8fARG(UTF, RExC_precomp_end - RExC_precomp, |
| 2662 | RExC_precomp))); |
| 2663 | } |
| 2664 | |
| 2665 | if ( ( minnext > 0 && mincount >= SSize_t_MAX / minnext ) |
| 2666 | || min >= SSize_t_MAX - minnext * mincount ) |
| 2667 | { |
| 2668 | FAIL("Regexp out of space"); |
| 2669 | } |
| 2670 | |
| 2671 | min += minnext * mincount; |
| 2672 | is_inf_internal |= deltanext == OPTIMIZE_INFTY |
| 2673 | || (maxcount == REG_INFTY && minnext + deltanext > 0); |
| 2674 | is_inf |= is_inf_internal; |
| 2675 | if (is_inf) { |
| 2676 | delta = OPTIMIZE_INFTY; |
| 2677 | } else { |
| 2678 | delta += (minnext + deltanext) * maxcount |
| 2679 | - minnext * mincount; |
| 2680 | } |
| 2681 | |
| 2682 | if (data && data->flags & SCF_SEEN_ACCEPT) { |
| 2683 | if (flags & SCF_DO_SUBSTR) { |
| 2684 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2685 | flags &= ~SCF_DO_SUBSTR; |
| 2686 | } |
| 2687 | if (stopmin > min) |
| 2688 | stopmin = min; |
| 2689 | DEBUG_STUDYDATA("after-whilem accept", data, depth, is_inf, min, stopmin, delta); |
| 2690 | } |
| 2691 | DEBUG_STUDYDATA("PRE CURLYX_TO_CURLYN", data, depth, is_inf, min, stopmin, delta); |
| 2692 | /* Try powerful optimization CURLYX => CURLYN. */ |
| 2693 | if ( RE_OPTIMIZE_CURLYX_TO_CURLYN |
| 2694 | && OP(oscan) == CURLYX |
| 2695 | && data |
| 2696 | && !pRExC_state->code_blocks /* XXX: for now disable whenever eval |
| 2697 | is seen anywhere. We need a better |
| 2698 | way. */ |
| 2699 | && ( ( data->flags & (SF_IN_PAR|SF_HAS_EVAL) ) == SF_IN_PAR ) |
| 2700 | && !deltanext |
| 2701 | && minnext == 1 |
| 2702 | && mutate_ok |
| 2703 | ) { |
| 2704 | DEBUG_STUDYDATA("CURLYX_TO_CURLYN", data, depth, is_inf, min, stopmin, delta); |
| 2705 | /* Try to optimize to CURLYN. */ |
| 2706 | regnode *nxt = REGNODE_AFTER_type(oscan, tregnode_CURLYX); |
| 2707 | regnode * const nxt1 = nxt; |
| 2708 | #ifdef DEBUGGING |
| 2709 | regnode *nxt2; |
| 2710 | #endif |
| 2711 | /* Skip open. */ |
| 2712 | nxt = regnext(nxt); |
| 2713 | if (!REGNODE_SIMPLE(OP(nxt)) |
| 2714 | && !(REGNODE_TYPE(OP(nxt)) == EXACT |
| 2715 | && STR_LEN(nxt) == 1)) |
| 2716 | goto nogo; |
| 2717 | #ifdef DEBUGGING |
| 2718 | nxt2 = nxt; |
| 2719 | #endif |
| 2720 | nxt = regnext(nxt); |
| 2721 | if (OP(nxt) != CLOSE) |
| 2722 | goto nogo; |
| 2723 | if (RExC_open_parens) { |
| 2724 | |
| 2725 | /*open->CURLYM*/ |
| 2726 | RExC_open_parens[PARNO(nxt1)] = REGNODE_OFFSET(oscan); |
| 2727 | |
| 2728 | /*close->while*/ |
| 2729 | RExC_close_parens[PARNO(nxt1)] = REGNODE_OFFSET(nxt) + 2; |
| 2730 | } |
| 2731 | /* Now we know that nxt2 is the only contents: */ |
| 2732 | oscan->flags = (U8)PARNO(nxt); |
| 2733 | OP(oscan) = CURLYN; |
| 2734 | OP(nxt1) = NOTHING; /* was OPEN. */ |
| 2735 | |
| 2736 | #ifdef DEBUGGING |
| 2737 | OP(nxt1 + 1) = OPTIMIZED; /* was count. */ |
| 2738 | NEXT_OFF(nxt1+ 1) = 0; /* just for consistency. */ |
| 2739 | NEXT_OFF(nxt2) = 0; /* just for consistency with CURLY. */ |
| 2740 | OP(nxt) = OPTIMIZED; /* was CLOSE. */ |
| 2741 | OP(nxt + 1) = OPTIMIZED; /* was count. */ |
| 2742 | NEXT_OFF(nxt+ 1) = 0; /* just for consistency. */ |
| 2743 | #endif |
| 2744 | } |
| 2745 | nogo: |
| 2746 | |
| 2747 | DEBUG_STUDYDATA("PRE CURLYX_TO_CURLYM", data, depth, is_inf, min, stopmin, delta); |
| 2748 | |
| 2749 | /* Try optimization CURLYX => CURLYM. */ |
| 2750 | if ( RE_OPTIMIZE_CURLYX_TO_CURLYM |
| 2751 | && OP(oscan) == CURLYX |
| 2752 | && data |
| 2753 | && !pRExC_state->code_blocks /* XXX: for now disable whenever eval |
| 2754 | is seen anywhere. We need a better |
| 2755 | way. */ |
| 2756 | && !(data->flags & (SF_HAS_PAR|SF_HAS_EVAL)) |
| 2757 | && !deltanext /* atom is fixed width */ |
| 2758 | && minnext != 0 /* CURLYM can't handle zero width */ |
| 2759 | /* Nor characters whose fold at run-time may be |
| 2760 | * multi-character */ |
| 2761 | && !(RExC_seen & REG_UNFOLDED_MULTI_SEEN) |
| 2762 | && mutate_ok |
| 2763 | ) { |
| 2764 | DEBUG_STUDYDATA("CURLYX_TO_CURLYM", data, depth, is_inf, min, stopmin, delta); |
| 2765 | /* XXXX How to optimize if data == 0? */ |
| 2766 | /* Optimize to a simpler form. */ |
| 2767 | regnode *nxt = REGNODE_AFTER_type(oscan, tregnode_CURLYX); /* OPEN */ |
| 2768 | regnode *nxt2; |
| 2769 | |
| 2770 | OP(oscan) = CURLYM; |
| 2771 | while ( (nxt2 = regnext(nxt)) /* skip over embedded stuff*/ |
| 2772 | && (OP(nxt2) != WHILEM)) |
| 2773 | nxt = nxt2; |
| 2774 | OP(nxt2) = SUCCEED; /* Whas WHILEM */ |
| 2775 | /* Need to optimize away parenths. */ |
| 2776 | if ((data->flags & SF_IN_PAR) && OP(nxt) == CLOSE) { |
| 2777 | /* Set the parenth number. */ |
| 2778 | /* note that we have changed the type of oscan to CURLYM here */ |
| 2779 | regnode *nxt1 = REGNODE_AFTER_type(oscan, tregnode_CURLYM); /* OPEN*/ |
| 2780 | |
| 2781 | oscan->flags = (U8)PARNO(nxt); |
| 2782 | if (RExC_open_parens) { |
| 2783 | /*open->CURLYM*/ |
| 2784 | RExC_open_parens[PARNO(nxt1)] = REGNODE_OFFSET(oscan); |
| 2785 | |
| 2786 | /*close->NOTHING*/ |
| 2787 | RExC_close_parens[PARNO(nxt1)] = REGNODE_OFFSET(nxt2) |
| 2788 | + 1; |
| 2789 | } |
| 2790 | OP(nxt1) = OPTIMIZED; /* was OPEN. */ |
| 2791 | OP(nxt) = OPTIMIZED; /* was CLOSE. */ |
| 2792 | |
| 2793 | #ifdef DEBUGGING |
| 2794 | OP(nxt1 + 1) = OPTIMIZED; /* was count. */ |
| 2795 | OP(nxt + 1) = OPTIMIZED; /* was count. */ |
| 2796 | NEXT_OFF(nxt1 + 1) = 0; /* just for consistency. */ |
| 2797 | NEXT_OFF(nxt + 1) = 0; /* just for consistency. */ |
| 2798 | #endif |
| 2799 | #if 0 |
| 2800 | while ( nxt1 && (OP(nxt1) != WHILEM)) { |
| 2801 | regnode *nnxt = regnext(nxt1); |
| 2802 | if (nnxt == nxt) { |
| 2803 | if (REGNODE_OFF_BY_ARG(OP(nxt1))) |
| 2804 | ARG_SET(nxt1, nxt2 - nxt1); |
| 2805 | else if (nxt2 - nxt1 < U16_MAX) |
| 2806 | NEXT_OFF(nxt1) = nxt2 - nxt1; |
| 2807 | else |
| 2808 | OP(nxt) = NOTHING; /* Cannot beautify */ |
| 2809 | } |
| 2810 | nxt1 = nnxt; |
| 2811 | } |
| 2812 | #endif |
| 2813 | /* Optimize again: */ |
| 2814 | /* recurse study_chunk() on optimised CURLYX => CURLYM */ |
| 2815 | study_chunk(pRExC_state, &nxt1, minlenp, &deltanext, nxt, |
| 2816 | NULL, stopparen, recursed_depth, NULL, 0, |
| 2817 | depth+1, mutate_ok); |
| 2818 | } |
| 2819 | else |
| 2820 | oscan->flags = 0; |
| 2821 | } |
| 2822 | else if ((OP(oscan) == CURLYX) |
| 2823 | && (flags & SCF_WHILEM_VISITED_POS) |
| 2824 | /* See the comment on a similar expression above. |
| 2825 | However, this time it's not a subexpression |
| 2826 | we care about, but the expression itself. */ |
| 2827 | && (maxcount == REG_INFTY) |
| 2828 | && data) { |
| 2829 | /* This stays as CURLYX, we can put the count/of pair. */ |
| 2830 | /* Find WHILEM (as in regexec.c) */ |
| 2831 | regnode *nxt = oscan + NEXT_OFF(oscan); |
| 2832 | |
| 2833 | if (OP(REGNODE_BEFORE(nxt)) == NOTHING) /* LONGJMP */ |
| 2834 | nxt += ARG(nxt); |
| 2835 | nxt = REGNODE_BEFORE(nxt); |
| 2836 | if (nxt->flags & 0xf) { |
| 2837 | /* we've already set whilem count on this node */ |
| 2838 | } else if (++data->whilem_c < 16) { |
| 2839 | assert(data->whilem_c <= RExC_whilem_seen); |
| 2840 | nxt->flags = (U8)(data->whilem_c |
| 2841 | | (RExC_whilem_seen << 4)); /* On WHILEM */ |
| 2842 | } |
| 2843 | } |
| 2844 | if (data && fl & (SF_HAS_PAR|SF_IN_PAR)) |
| 2845 | pars++; |
| 2846 | if (flags & SCF_DO_SUBSTR) { |
| 2847 | SV *last_str = NULL; |
| 2848 | STRLEN last_chrs = 0; |
| 2849 | int counted = mincount != 0; |
| 2850 | |
| 2851 | if (data->last_end > 0 && mincount != 0) { /* Ends with a |
| 2852 | string. */ |
| 2853 | SSize_t b = pos_before >= data->last_start_min |
| 2854 | ? pos_before : data->last_start_min; |
| 2855 | STRLEN l; |
| 2856 | const char * const s = SvPV_const(data->last_found, l); |
| 2857 | SSize_t old = b - data->last_start_min; |
| 2858 | assert(old >= 0); |
| 2859 | |
| 2860 | if (UTF) |
| 2861 | old = utf8_hop_forward((U8*)s, old, |
| 2862 | (U8 *) SvEND(data->last_found)) |
| 2863 | - (U8*)s; |
| 2864 | l -= old; |
| 2865 | /* Get the added string: */ |
| 2866 | last_str = newSVpvn_utf8(s + old, l, UTF); |
| 2867 | last_chrs = UTF ? utf8_length((U8*)(s + old), |
| 2868 | (U8*)(s + old + l)) : l; |
| 2869 | if (deltanext == 0 && pos_before == b) { |
| 2870 | /* What was added is a constant string */ |
| 2871 | if (mincount > 1) { |
| 2872 | |
| 2873 | SvGROW(last_str, (mincount * l) + 1); |
| 2874 | repeatcpy(SvPVX(last_str) + l, |
| 2875 | SvPVX_const(last_str), l, |
| 2876 | mincount - 1); |
| 2877 | SvCUR_set(last_str, SvCUR(last_str) * mincount); |
| 2878 | /* Add additional parts. */ |
| 2879 | SvCUR_set(data->last_found, |
| 2880 | SvCUR(data->last_found) - l); |
| 2881 | sv_catsv(data->last_found, last_str); |
| 2882 | { |
| 2883 | SV * sv = data->last_found; |
| 2884 | MAGIC *mg = |
| 2885 | SvUTF8(sv) && SvMAGICAL(sv) ? |
| 2886 | mg_find(sv, PERL_MAGIC_utf8) : NULL; |
| 2887 | if (mg && mg->mg_len >= 0) |
| 2888 | mg->mg_len += last_chrs * (mincount-1); |
| 2889 | } |
| 2890 | last_chrs *= mincount; |
| 2891 | data->last_end += l * (mincount - 1); |
| 2892 | } |
| 2893 | } else { |
| 2894 | /* start offset must point into the last copy */ |
| 2895 | data->last_start_min += minnext * (mincount - 1); |
| 2896 | data->last_start_max = |
| 2897 | is_inf |
| 2898 | ? OPTIMIZE_INFTY |
| 2899 | : data->last_start_max + |
| 2900 | (maxcount - 1) * (minnext + data->pos_delta); |
| 2901 | } |
| 2902 | } |
| 2903 | /* It is counted once already... */ |
| 2904 | data->pos_min += minnext * (mincount - counted); |
| 2905 | #if 0 |
| 2906 | Perl_re_printf( aTHX_ "counted=%" UVuf " deltanext=%" UVuf |
| 2907 | " OPTIMIZE_INFTY=%" UVuf " minnext=%" UVuf |
| 2908 | " maxcount=%" UVuf " mincount=%" UVuf |
| 2909 | " data->pos_delta=%" UVuf "\n", |
| 2910 | (UV)counted, (UV)deltanext, (UV)OPTIMIZE_INFTY, (UV)minnext, |
| 2911 | (UV)maxcount, (UV)mincount, (UV)data->pos_delta); |
| 2912 | if (deltanext != OPTIMIZE_INFTY) |
| 2913 | Perl_re_printf( aTHX_ "LHS=%" UVuf " RHS=%" UVuf "\n", |
| 2914 | (UV)(-counted * deltanext + (minnext + deltanext) * maxcount |
| 2915 | - minnext * mincount), (UV)(OPTIMIZE_INFTY - data->pos_delta)); |
| 2916 | #endif |
| 2917 | if (deltanext == OPTIMIZE_INFTY |
| 2918 | || data->pos_delta == OPTIMIZE_INFTY |
| 2919 | || -counted * deltanext + (minnext + deltanext) * maxcount - minnext * mincount >= OPTIMIZE_INFTY - data->pos_delta) |
| 2920 | data->pos_delta = OPTIMIZE_INFTY; |
| 2921 | else |
| 2922 | data->pos_delta += - counted * deltanext + |
| 2923 | (minnext + deltanext) * maxcount - minnext * mincount; |
| 2924 | if (mincount != maxcount) { |
| 2925 | /* Cannot extend fixed substrings found inside |
| 2926 | the group. */ |
| 2927 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2928 | if (mincount && last_str) { |
| 2929 | SV * const sv = data->last_found; |
| 2930 | MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ? |
| 2931 | mg_find(sv, PERL_MAGIC_utf8) : NULL; |
| 2932 | |
| 2933 | if (mg) |
| 2934 | mg->mg_len = -1; |
| 2935 | sv_setsv(sv, last_str); |
| 2936 | data->last_end = data->pos_min; |
| 2937 | data->last_start_min = data->pos_min - last_chrs; |
| 2938 | data->last_start_max = is_inf |
| 2939 | ? OPTIMIZE_INFTY |
| 2940 | : data->pos_min + data->pos_delta - last_chrs; |
| 2941 | } |
| 2942 | data->cur_is_floating = 1; /* float */ |
| 2943 | } |
| 2944 | SvREFCNT_dec(last_str); |
| 2945 | } |
| 2946 | if (data && (fl & SF_HAS_EVAL)) |
| 2947 | data->flags |= SF_HAS_EVAL; |
| 2948 | optimize_curly_tail: |
| 2949 | rck_elide_nothing(oscan); |
| 2950 | continue; |
| 2951 | |
| 2952 | default: |
| 2953 | Perl_croak(aTHX_ "panic: unexpected varying REx opcode %d", |
| 2954 | OP(scan)); |
| 2955 | case REF: |
| 2956 | case CLUMP: |
| 2957 | if (flags & SCF_DO_SUBSTR) { |
| 2958 | /* Cannot expect anything... */ |
| 2959 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 2960 | data->cur_is_floating = 1; /* float */ |
| 2961 | } |
| 2962 | is_inf = is_inf_internal = 1; |
| 2963 | if (flags & SCF_DO_STCLASS_OR) { |
| 2964 | if (OP(scan) == CLUMP) { |
| 2965 | /* Actually is any start char, but very few code points |
| 2966 | * aren't start characters */ |
| 2967 | ssc_match_all_cp(data->start_class); |
| 2968 | } |
| 2969 | else { |
| 2970 | ssc_anything(data->start_class); |
| 2971 | } |
| 2972 | } |
| 2973 | flags &= ~SCF_DO_STCLASS; |
| 2974 | break; |
| 2975 | } |
| 2976 | } |
| 2977 | else if (OP(scan) == LNBREAK) { |
| 2978 | if (flags & SCF_DO_STCLASS) { |
| 2979 | if (flags & SCF_DO_STCLASS_AND) { |
| 2980 | ssc_intersection(data->start_class, |
| 2981 | PL_XPosix_ptrs[CC_VERTSPACE_], FALSE); |
| 2982 | ssc_clear_locale(data->start_class); |
| 2983 | ANYOF_FLAGS(data->start_class) |
| 2984 | &= ~SSC_MATCHES_EMPTY_STRING; |
| 2985 | } |
| 2986 | else if (flags & SCF_DO_STCLASS_OR) { |
| 2987 | ssc_union(data->start_class, |
| 2988 | PL_XPosix_ptrs[CC_VERTSPACE_], |
| 2989 | FALSE); |
| 2990 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 2991 | |
| 2992 | /* See commit msg for |
| 2993 | * 749e076fceedeb708a624933726e7989f2302f6a */ |
| 2994 | ANYOF_FLAGS(data->start_class) |
| 2995 | &= ~SSC_MATCHES_EMPTY_STRING; |
| 2996 | } |
| 2997 | flags &= ~SCF_DO_STCLASS; |
| 2998 | } |
| 2999 | min++; |
| 3000 | if (delta != OPTIMIZE_INFTY) |
| 3001 | delta++; /* Because of the 2 char string cr-lf */ |
| 3002 | if (flags & SCF_DO_SUBSTR) { |
| 3003 | /* Cannot expect anything... */ |
| 3004 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3005 | data->pos_min += 1; |
| 3006 | if (data->pos_delta != OPTIMIZE_INFTY) { |
| 3007 | data->pos_delta += 1; |
| 3008 | } |
| 3009 | data->cur_is_floating = 1; /* float */ |
| 3010 | } |
| 3011 | } |
| 3012 | else if (REGNODE_SIMPLE(OP(scan))) { |
| 3013 | |
| 3014 | if (flags & SCF_DO_SUBSTR) { |
| 3015 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3016 | data->pos_min++; |
| 3017 | } |
| 3018 | min++; |
| 3019 | if (flags & SCF_DO_STCLASS) { |
| 3020 | bool invert = 0; |
| 3021 | SV* my_invlist = NULL; |
| 3022 | U8 namedclass; |
| 3023 | |
| 3024 | /* See commit msg 749e076fceedeb708a624933726e7989f2302f6a */ |
| 3025 | ANYOF_FLAGS(data->start_class) &= ~SSC_MATCHES_EMPTY_STRING; |
| 3026 | |
| 3027 | /* Some of the logic below assumes that switching |
| 3028 | locale on will only add false positives. */ |
| 3029 | switch (OP(scan)) { |
| 3030 | |
| 3031 | default: |
| 3032 | #ifdef DEBUGGING |
| 3033 | Perl_croak(aTHX_ "panic: unexpected simple REx opcode %d", |
| 3034 | OP(scan)); |
| 3035 | #endif |
| 3036 | case SANY: |
| 3037 | if (flags & SCF_DO_STCLASS_OR) /* Allow everything */ |
| 3038 | ssc_match_all_cp(data->start_class); |
| 3039 | break; |
| 3040 | |
| 3041 | case REG_ANY: |
| 3042 | { |
| 3043 | SV* REG_ANY_invlist = _new_invlist(2); |
| 3044 | REG_ANY_invlist = add_cp_to_invlist(REG_ANY_invlist, |
| 3045 | '\n'); |
| 3046 | if (flags & SCF_DO_STCLASS_OR) { |
| 3047 | ssc_union(data->start_class, |
| 3048 | REG_ANY_invlist, |
| 3049 | TRUE /* TRUE => invert, hence all but \n |
| 3050 | */ |
| 3051 | ); |
| 3052 | } |
| 3053 | else if (flags & SCF_DO_STCLASS_AND) { |
| 3054 | ssc_intersection(data->start_class, |
| 3055 | REG_ANY_invlist, |
| 3056 | TRUE /* TRUE => invert */ |
| 3057 | ); |
| 3058 | ssc_clear_locale(data->start_class); |
| 3059 | } |
| 3060 | SvREFCNT_dec_NN(REG_ANY_invlist); |
| 3061 | } |
| 3062 | break; |
| 3063 | |
| 3064 | case ANYOFD: |
| 3065 | case ANYOFL: |
| 3066 | case ANYOFPOSIXL: |
| 3067 | case ANYOFH: |
| 3068 | case ANYOFHb: |
| 3069 | case ANYOFHr: |
| 3070 | case ANYOFHs: |
| 3071 | case ANYOF: |
| 3072 | if (flags & SCF_DO_STCLASS_AND) |
| 3073 | ssc_and(pRExC_state, data->start_class, |
| 3074 | (regnode_charclass *) scan); |
| 3075 | else |
| 3076 | ssc_or(pRExC_state, data->start_class, |
| 3077 | (regnode_charclass *) scan); |
| 3078 | break; |
| 3079 | |
| 3080 | case ANYOFHbbm: |
| 3081 | { |
| 3082 | SV* cp_list = get_ANYOFHbbm_contents(scan); |
| 3083 | |
| 3084 | if (flags & SCF_DO_STCLASS_OR) { |
| 3085 | ssc_union(data->start_class, cp_list, invert); |
| 3086 | } |
| 3087 | else if (flags & SCF_DO_STCLASS_AND) { |
| 3088 | ssc_intersection(data->start_class, cp_list, invert); |
| 3089 | } |
| 3090 | |
| 3091 | SvREFCNT_dec_NN(cp_list); |
| 3092 | break; |
| 3093 | } |
| 3094 | |
| 3095 | case NANYOFM: /* NANYOFM already contains the inversion of the |
| 3096 | input ANYOF data, so, unlike things like |
| 3097 | NPOSIXA, don't change 'invert' to TRUE */ |
| 3098 | /* FALLTHROUGH */ |
| 3099 | case ANYOFM: |
| 3100 | { |
| 3101 | SV* cp_list = get_ANYOFM_contents(scan); |
| 3102 | |
| 3103 | if (flags & SCF_DO_STCLASS_OR) { |
| 3104 | ssc_union(data->start_class, cp_list, invert); |
| 3105 | } |
| 3106 | else if (flags & SCF_DO_STCLASS_AND) { |
| 3107 | ssc_intersection(data->start_class, cp_list, invert); |
| 3108 | } |
| 3109 | |
| 3110 | SvREFCNT_dec_NN(cp_list); |
| 3111 | break; |
| 3112 | } |
| 3113 | |
| 3114 | case ANYOFR: |
| 3115 | case ANYOFRb: |
| 3116 | { |
| 3117 | SV* cp_list = NULL; |
| 3118 | |
| 3119 | cp_list = _add_range_to_invlist(cp_list, |
| 3120 | ANYOFRbase(scan), |
| 3121 | ANYOFRbase(scan) + ANYOFRdelta(scan)); |
| 3122 | |
| 3123 | if (flags & SCF_DO_STCLASS_OR) { |
| 3124 | ssc_union(data->start_class, cp_list, invert); |
| 3125 | } |
| 3126 | else if (flags & SCF_DO_STCLASS_AND) { |
| 3127 | ssc_intersection(data->start_class, cp_list, invert); |
| 3128 | } |
| 3129 | |
| 3130 | SvREFCNT_dec_NN(cp_list); |
| 3131 | break; |
| 3132 | } |
| 3133 | |
| 3134 | case NPOSIXL: |
| 3135 | invert = 1; |
| 3136 | /* FALLTHROUGH */ |
| 3137 | |
| 3138 | case POSIXL: |
| 3139 | namedclass = classnum_to_namedclass(FLAGS(scan)) + invert; |
| 3140 | if (flags & SCF_DO_STCLASS_AND) { |
| 3141 | bool was_there = cBOOL( |
| 3142 | ANYOF_POSIXL_TEST(data->start_class, |
| 3143 | namedclass)); |
| 3144 | ANYOF_POSIXL_ZERO(data->start_class); |
| 3145 | if (was_there) { /* Do an AND */ |
| 3146 | ANYOF_POSIXL_SET(data->start_class, namedclass); |
| 3147 | } |
| 3148 | /* No individual code points can now match */ |
| 3149 | data->start_class->invlist |
| 3150 | = sv_2mortal(_new_invlist(0)); |
| 3151 | } |
| 3152 | else { |
| 3153 | int complement = namedclass + ((invert) ? -1 : 1); |
| 3154 | |
| 3155 | assert(flags & SCF_DO_STCLASS_OR); |
| 3156 | |
| 3157 | /* If the complement of this class was already there, |
| 3158 | * the result is that they match all code points, |
| 3159 | * (\d + \D == everything). Remove the classes from |
| 3160 | * future consideration. Locale is not relevant in |
| 3161 | * this case */ |
| 3162 | if (ANYOF_POSIXL_TEST(data->start_class, complement)) { |
| 3163 | ssc_match_all_cp(data->start_class); |
| 3164 | ANYOF_POSIXL_CLEAR(data->start_class, namedclass); |
| 3165 | ANYOF_POSIXL_CLEAR(data->start_class, complement); |
| 3166 | } |
| 3167 | else { /* The usual case; just add this class to the |
| 3168 | existing set */ |
| 3169 | ANYOF_POSIXL_SET(data->start_class, namedclass); |
| 3170 | } |
| 3171 | } |
| 3172 | break; |
| 3173 | |
| 3174 | case NPOSIXA: /* For these, we always know the exact set of |
| 3175 | what's matched */ |
| 3176 | invert = 1; |
| 3177 | /* FALLTHROUGH */ |
| 3178 | case POSIXA: |
| 3179 | my_invlist = invlist_clone(PL_Posix_ptrs[FLAGS(scan)], NULL); |
| 3180 | goto join_posix_and_ascii; |
| 3181 | |
| 3182 | case NPOSIXD: |
| 3183 | case NPOSIXU: |
| 3184 | invert = 1; |
| 3185 | /* FALLTHROUGH */ |
| 3186 | case POSIXD: |
| 3187 | case POSIXU: |
| 3188 | my_invlist = invlist_clone(PL_XPosix_ptrs[FLAGS(scan)], NULL); |
| 3189 | |
| 3190 | /* NPOSIXD matches all upper Latin1 code points unless the |
| 3191 | * target string being matched is UTF-8, which is |
| 3192 | * unknowable until match time. Since we are going to |
| 3193 | * invert, we want to get rid of all of them so that the |
| 3194 | * inversion will match all */ |
| 3195 | if (OP(scan) == NPOSIXD) { |
| 3196 | _invlist_subtract(my_invlist, PL_UpperLatin1, |
| 3197 | &my_invlist); |
| 3198 | } |
| 3199 | |
| 3200 | join_posix_and_ascii: |
| 3201 | |
| 3202 | if (flags & SCF_DO_STCLASS_AND) { |
| 3203 | ssc_intersection(data->start_class, my_invlist, invert); |
| 3204 | ssc_clear_locale(data->start_class); |
| 3205 | } |
| 3206 | else { |
| 3207 | assert(flags & SCF_DO_STCLASS_OR); |
| 3208 | ssc_union(data->start_class, my_invlist, invert); |
| 3209 | } |
| 3210 | SvREFCNT_dec(my_invlist); |
| 3211 | } |
| 3212 | if (flags & SCF_DO_STCLASS_OR) |
| 3213 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 3214 | flags &= ~SCF_DO_STCLASS; |
| 3215 | } |
| 3216 | } |
| 3217 | else if (REGNODE_TYPE(OP(scan)) == EOL && flags & SCF_DO_SUBSTR) { |
| 3218 | data->flags |= (OP(scan) == MEOL |
| 3219 | ? SF_BEFORE_MEOL |
| 3220 | : SF_BEFORE_SEOL); |
| 3221 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3222 | |
| 3223 | } |
| 3224 | else if ( REGNODE_TYPE(OP(scan)) == BRANCHJ |
| 3225 | /* Lookbehind, or need to calculate parens/evals/stclass: */ |
| 3226 | && (scan->flags || data || (flags & SCF_DO_STCLASS)) |
| 3227 | && (OP(scan) == IFMATCH || OP(scan) == UNLESSM)) |
| 3228 | { |
| 3229 | if ( !PERL_ENABLE_POSITIVE_ASSERTION_STUDY |
| 3230 | || OP(scan) == UNLESSM ) |
| 3231 | { |
| 3232 | /* Negative Lookahead/lookbehind |
| 3233 | In this case we can't do fixed string optimisation. |
| 3234 | */ |
| 3235 | |
| 3236 | bool is_positive = OP(scan) == IFMATCH ? 1 : 0; |
| 3237 | SSize_t deltanext, minnext; |
| 3238 | SSize_t fake_last_close = 0; |
| 3239 | regnode *fake_last_close_op = NULL; |
| 3240 | regnode *cur_last_close_op; |
| 3241 | regnode *nscan; |
| 3242 | regnode_ssc intrnl; |
| 3243 | U32 f = (flags & SCF_TRIE_DOING_RESTUDY); |
| 3244 | |
| 3245 | StructCopy(&zero_scan_data, &data_fake, scan_data_t); |
| 3246 | if (data) { |
| 3247 | data_fake.whilem_c = data->whilem_c; |
| 3248 | data_fake.last_closep = data->last_closep; |
| 3249 | data_fake.last_close_opp = data->last_close_opp; |
| 3250 | } |
| 3251 | else { |
| 3252 | data_fake.last_closep = &fake_last_close; |
| 3253 | data_fake.last_close_opp = &fake_last_close_op; |
| 3254 | } |
| 3255 | |
| 3256 | /* remember the last_close_op we saw so we can see if |
| 3257 | * we are dealing with variable length lookbehind that |
| 3258 | * contains capturing buffers, which are considered |
| 3259 | * experimental */ |
| 3260 | cur_last_close_op= *(data_fake.last_close_opp); |
| 3261 | |
| 3262 | data_fake.pos_delta = delta; |
| 3263 | if ( flags & SCF_DO_STCLASS && !scan->flags |
| 3264 | && OP(scan) == IFMATCH ) { /* Lookahead */ |
| 3265 | ssc_init(pRExC_state, &intrnl); |
| 3266 | data_fake.start_class = &intrnl; |
| 3267 | f |= SCF_DO_STCLASS_AND; |
| 3268 | } |
| 3269 | if (flags & SCF_WHILEM_VISITED_POS) |
| 3270 | f |= SCF_WHILEM_VISITED_POS; |
| 3271 | next = regnext(scan); |
| 3272 | nscan = REGNODE_AFTER(scan); |
| 3273 | |
| 3274 | /* recurse study_chunk() for lookahead body */ |
| 3275 | minnext = study_chunk(pRExC_state, &nscan, minlenp, &deltanext, |
| 3276 | last, &data_fake, stopparen, |
| 3277 | recursed_depth, NULL, f, depth+1, |
| 3278 | mutate_ok); |
| 3279 | |
| 3280 | if (scan->flags) { |
| 3281 | if ( deltanext < 0 |
| 3282 | || deltanext > (I32) U8_MAX |
| 3283 | || minnext > (I32)U8_MAX |
| 3284 | || minnext + deltanext > (I32)U8_MAX) |
| 3285 | { |
| 3286 | FAIL2("Lookbehind longer than %" UVuf " not implemented", |
| 3287 | (UV)U8_MAX); |
| 3288 | } |
| 3289 | |
| 3290 | /* The 'next_off' field has been repurposed to count the |
| 3291 | * additional starting positions to try beyond the initial |
| 3292 | * one. (This leaves it at 0 for non-variable length |
| 3293 | * matches to avoid breakage for those not using this |
| 3294 | * extension) */ |
| 3295 | if (deltanext) { |
| 3296 | scan->next_off = deltanext; |
| 3297 | if ( |
| 3298 | /* See a CLOSE op inside this lookbehind? */ |
| 3299 | cur_last_close_op != *(data_fake.last_close_opp) |
| 3300 | /* and not doing restudy. see: restudied */ |
| 3301 | && !(flags & SCF_TRIE_DOING_RESTUDY) |
| 3302 | ) { |
| 3303 | /* this is positive variable length lookbehind with |
| 3304 | * capture buffers inside of it */ |
| 3305 | ckWARNexperimental_with_arg(RExC_parse, |
| 3306 | WARN_EXPERIMENTAL__VLB, |
| 3307 | "Variable length %s lookbehind with capturing is experimental", |
| 3308 | is_positive ? "positive" : "negative"); |
| 3309 | } |
| 3310 | } |
| 3311 | scan->flags = (U8)minnext + deltanext; |
| 3312 | } |
| 3313 | if (data) { |
| 3314 | if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR)) |
| 3315 | pars++; |
| 3316 | if (data_fake.flags & SF_HAS_EVAL) |
| 3317 | data->flags |= SF_HAS_EVAL; |
| 3318 | data->whilem_c = data_fake.whilem_c; |
| 3319 | } |
| 3320 | if (f & SCF_DO_STCLASS_AND) { |
| 3321 | if (flags & SCF_DO_STCLASS_OR) { |
| 3322 | /* OR before, AND after: ideally we would recurse with |
| 3323 | * data_fake to get the AND applied by study of the |
| 3324 | * remainder of the pattern, and then derecurse; |
| 3325 | * *** HACK *** for now just treat as "no information". |
| 3326 | * See [perl #56690]. |
| 3327 | */ |
| 3328 | ssc_init(pRExC_state, data->start_class); |
| 3329 | } else { |
| 3330 | /* AND before and after: combine and continue. These |
| 3331 | * assertions are zero-length, so can match an EMPTY |
| 3332 | * string */ |
| 3333 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) &intrnl); |
| 3334 | ANYOF_FLAGS(data->start_class) |
| 3335 | |= SSC_MATCHES_EMPTY_STRING; |
| 3336 | } |
| 3337 | } |
| 3338 | DEBUG_STUDYDATA("end LOOKAROUND", data, depth, is_inf, min, stopmin, delta); |
| 3339 | } |
| 3340 | #if PERL_ENABLE_POSITIVE_ASSERTION_STUDY |
| 3341 | else { |
| 3342 | /* Positive Lookahead/lookbehind |
| 3343 | In this case we can do fixed string optimisation, |
| 3344 | but we must be careful about it. Note in the case of |
| 3345 | lookbehind the positions will be offset by the minimum |
| 3346 | length of the pattern, something we won't know about |
| 3347 | until after the recurse. |
| 3348 | */ |
| 3349 | SSize_t deltanext, fake_last_close = 0; |
| 3350 | regnode *last_close_op = NULL; |
| 3351 | regnode *nscan; |
| 3352 | regnode_ssc intrnl; |
| 3353 | U32 f = (flags & SCF_TRIE_DOING_RESTUDY); |
| 3354 | /* We use SAVEFREEPV so that when the full compile |
| 3355 | is finished perl will clean up the allocated |
| 3356 | minlens when it's all done. This way we don't |
| 3357 | have to worry about freeing them when we know |
| 3358 | they wont be used, which would be a pain. |
| 3359 | */ |
| 3360 | SSize_t *minnextp; |
| 3361 | Newx( minnextp, 1, SSize_t ); |
| 3362 | SAVEFREEPV(minnextp); |
| 3363 | |
| 3364 | if (data) { |
| 3365 | StructCopy(data, &data_fake, scan_data_t); |
| 3366 | if ((flags & SCF_DO_SUBSTR) && data->last_found) { |
| 3367 | f |= SCF_DO_SUBSTR; |
| 3368 | if (scan->flags) |
| 3369 | scan_commit(pRExC_state, &data_fake, minlenp, is_inf); |
| 3370 | data_fake.last_found=newSVsv(data->last_found); |
| 3371 | } |
| 3372 | } |
| 3373 | else { |
| 3374 | data_fake.last_closep = &fake_last_close; |
| 3375 | data_fake.last_close_opp = &fake_last_close_opp; |
| 3376 | } |
| 3377 | data_fake.flags = 0; |
| 3378 | data_fake.substrs[0].flags = 0; |
| 3379 | data_fake.substrs[1].flags = 0; |
| 3380 | data_fake.pos_delta = delta; |
| 3381 | if (is_inf) |
| 3382 | data_fake.flags |= SF_IS_INF; |
| 3383 | if ( flags & SCF_DO_STCLASS && !scan->flags |
| 3384 | && OP(scan) == IFMATCH ) { /* Lookahead */ |
| 3385 | ssc_init(pRExC_state, &intrnl); |
| 3386 | data_fake.start_class = &intrnl; |
| 3387 | f |= SCF_DO_STCLASS_AND; |
| 3388 | } |
| 3389 | if (flags & SCF_WHILEM_VISITED_POS) |
| 3390 | f |= SCF_WHILEM_VISITED_POS; |
| 3391 | next = regnext(scan); |
| 3392 | nscan = REGNODE_AFTER(scan); |
| 3393 | |
| 3394 | /* positive lookahead study_chunk() recursion */ |
| 3395 | *minnextp = study_chunk(pRExC_state, &nscan, minnextp, |
| 3396 | &deltanext, last, &data_fake, |
| 3397 | stopparen, recursed_depth, NULL, |
| 3398 | f, depth+1, mutate_ok); |
| 3399 | if (scan->flags) { |
| 3400 | assert(0); /* This code has never been tested since this |
| 3401 | is normally not compiled */ |
| 3402 | if ( deltanext < 0 |
| 3403 | || deltanext > (I32) U8_MAX |
| 3404 | || *minnextp > (I32)U8_MAX |
| 3405 | || *minnextp + deltanext > (I32)U8_MAX) |
| 3406 | { |
| 3407 | FAIL2("Lookbehind longer than %" UVuf " not implemented", |
| 3408 | (UV)U8_MAX); |
| 3409 | } |
| 3410 | |
| 3411 | if (deltanext) { |
| 3412 | scan->next_off = deltanext; |
| 3413 | } |
| 3414 | scan->flags = (U8)*minnextp + deltanext; |
| 3415 | } |
| 3416 | |
| 3417 | *minnextp += min; |
| 3418 | |
| 3419 | if (f & SCF_DO_STCLASS_AND) { |
| 3420 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) &intrnl); |
| 3421 | ANYOF_FLAGS(data->start_class) |= SSC_MATCHES_EMPTY_STRING; |
| 3422 | } |
| 3423 | if (data) { |
| 3424 | if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR)) |
| 3425 | pars++; |
| 3426 | if (data_fake.flags & SF_HAS_EVAL) |
| 3427 | data->flags |= SF_HAS_EVAL; |
| 3428 | data->whilem_c = data_fake.whilem_c; |
| 3429 | if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) { |
| 3430 | int i; |
| 3431 | if (RExC_rx->minlen < *minnextp) |
| 3432 | RExC_rx->minlen = *minnextp; |
| 3433 | scan_commit(pRExC_state, &data_fake, minnextp, is_inf); |
| 3434 | SvREFCNT_dec_NN(data_fake.last_found); |
| 3435 | |
| 3436 | for (i = 0; i < 2; i++) { |
| 3437 | if (data_fake.substrs[i].minlenp != minlenp) { |
| 3438 | data->substrs[i].min_offset = |
| 3439 | data_fake.substrs[i].min_offset; |
| 3440 | data->substrs[i].max_offset = |
| 3441 | data_fake.substrs[i].max_offset; |
| 3442 | data->substrs[i].minlenp = |
| 3443 | data_fake.substrs[i].minlenp; |
| 3444 | data->substrs[i].lookbehind += scan->flags; |
| 3445 | } |
| 3446 | } |
| 3447 | } |
| 3448 | } |
| 3449 | } |
| 3450 | #endif |
| 3451 | } |
| 3452 | else if (OP(scan) == OPEN) { |
| 3453 | if (stopparen != (I32)PARNO(scan)) |
| 3454 | pars++; |
| 3455 | } |
| 3456 | else if (OP(scan) == CLOSE) { |
| 3457 | if (stopparen == (I32)PARNO(scan)) { |
| 3458 | break; |
| 3459 | } |
| 3460 | if ((I32)PARNO(scan) == is_par) { |
| 3461 | next = regnext(scan); |
| 3462 | |
| 3463 | if ( next && (OP(next) != WHILEM) && next < last) |
| 3464 | is_par = 0; /* Disable optimization */ |
| 3465 | } |
| 3466 | if (data) { |
| 3467 | *(data->last_closep) = PARNO(scan); |
| 3468 | *(data->last_close_opp) = scan; |
| 3469 | } |
| 3470 | } |
| 3471 | else if (OP(scan) == EVAL) { |
| 3472 | if (data) |
| 3473 | data->flags |= SF_HAS_EVAL; |
| 3474 | } |
| 3475 | else if ( REGNODE_TYPE(OP(scan)) == ENDLIKE ) { |
| 3476 | if (flags & SCF_DO_SUBSTR) { |
| 3477 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3478 | flags &= ~SCF_DO_SUBSTR; |
| 3479 | } |
| 3480 | if (OP(scan)==ACCEPT) { |
| 3481 | /* m{(*ACCEPT)x} does not have to start with 'x' */ |
| 3482 | flags &= ~SCF_DO_STCLASS; |
| 3483 | if (data) |
| 3484 | data->flags |= SCF_SEEN_ACCEPT; |
| 3485 | if (stopmin > min) |
| 3486 | stopmin = min; |
| 3487 | } |
| 3488 | } |
| 3489 | else if (OP(scan) == COMMIT) { |
| 3490 | /* gh18770: m{abc(*COMMIT)xyz} must fail on "abc abcxyz", so we |
| 3491 | * must not end up with "abcxyz" as a fixed substring else we'll |
| 3492 | * skip straight to attempting to match at offset 4. |
| 3493 | */ |
| 3494 | if (flags & SCF_DO_SUBSTR) { |
| 3495 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3496 | flags &= ~SCF_DO_SUBSTR; |
| 3497 | } |
| 3498 | } |
| 3499 | else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */ |
| 3500 | { |
| 3501 | if (flags & SCF_DO_SUBSTR) { |
| 3502 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3503 | data->cur_is_floating = 1; /* float */ |
| 3504 | } |
| 3505 | is_inf = is_inf_internal = 1; |
| 3506 | if (flags & SCF_DO_STCLASS_OR) /* Allow everything */ |
| 3507 | ssc_anything(data->start_class); |
| 3508 | flags &= ~SCF_DO_STCLASS; |
| 3509 | } |
| 3510 | else if (OP(scan) == GPOS) { |
| 3511 | if (!(RExC_rx->intflags & PREGf_GPOS_FLOAT) && |
| 3512 | !(delta || is_inf || (data && data->pos_delta))) |
| 3513 | { |
| 3514 | if (!(RExC_rx->intflags & PREGf_ANCH) && (flags & SCF_DO_SUBSTR)) |
| 3515 | RExC_rx->intflags |= PREGf_ANCH_GPOS; |
| 3516 | if (RExC_rx->gofs < (STRLEN)min) |
| 3517 | RExC_rx->gofs = min; |
| 3518 | } else { |
| 3519 | RExC_rx->intflags |= PREGf_GPOS_FLOAT; |
| 3520 | RExC_rx->gofs = 0; |
| 3521 | } |
| 3522 | } |
| 3523 | #ifdef TRIE_STUDY_OPT |
| 3524 | #ifdef FULL_TRIE_STUDY |
| 3525 | else if (REGNODE_TYPE(OP(scan)) == TRIE) { |
| 3526 | /* NOTE - There is similar code to this block above for handling |
| 3527 | BRANCH nodes on the initial study. If you change stuff here |
| 3528 | check there too. */ |
| 3529 | regnode *trie_node= scan; |
| 3530 | regnode *tail= regnext(scan); |
| 3531 | reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ]; |
| 3532 | SSize_t max1 = 0, min1 = OPTIMIZE_INFTY; |
| 3533 | regnode_ssc accum; |
| 3534 | |
| 3535 | if (flags & SCF_DO_SUBSTR) { /* XXXX Add !SUSPEND? */ |
| 3536 | /* Cannot merge strings after this. */ |
| 3537 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3538 | } |
| 3539 | if (flags & SCF_DO_STCLASS) |
| 3540 | ssc_init_zero(pRExC_state, &accum); |
| 3541 | |
| 3542 | if (!trie->jump) { |
| 3543 | min1= trie->minlen; |
| 3544 | max1= trie->maxlen; |
| 3545 | } else { |
| 3546 | const regnode *nextbranch= NULL; |
| 3547 | U32 word; |
| 3548 | |
| 3549 | for ( word=1 ; word <= trie->wordcount ; word++) |
| 3550 | { |
| 3551 | SSize_t deltanext = 0, minnext = 0; |
| 3552 | U32 f = (flags & SCF_TRIE_DOING_RESTUDY); |
| 3553 | SSize_t fake_last_close = 0; |
| 3554 | regnode *fake_last_close_op = NULL; |
| 3555 | regnode_ssc this_class; |
| 3556 | |
| 3557 | StructCopy(&zero_scan_data, &data_fake, scan_data_t); |
| 3558 | if (data) { |
| 3559 | data_fake.whilem_c = data->whilem_c; |
| 3560 | data_fake.last_closep = data->last_closep; |
| 3561 | data_fake.last_close_opp = data->last_close_opp; |
| 3562 | } |
| 3563 | else { |
| 3564 | data_fake.last_closep = &fake_last_close; |
| 3565 | data_fake.last_close_opp = &fake_last_close_op; |
| 3566 | } |
| 3567 | data_fake.pos_delta = delta; |
| 3568 | if (flags & SCF_DO_STCLASS) { |
| 3569 | ssc_init(pRExC_state, &this_class); |
| 3570 | data_fake.start_class = &this_class; |
| 3571 | f |= SCF_DO_STCLASS_AND; |
| 3572 | } |
| 3573 | if (flags & SCF_WHILEM_VISITED_POS) |
| 3574 | f |= SCF_WHILEM_VISITED_POS; |
| 3575 | |
| 3576 | if (trie->jump[word]) { |
| 3577 | if (!nextbranch) |
| 3578 | nextbranch = trie_node + trie->jump[0]; |
| 3579 | scan= trie_node + trie->jump[word]; |
| 3580 | /* We go from the jump point to the branch that follows |
| 3581 | it. Note this means we need the vestigal unused |
| 3582 | branches even though they arent otherwise used. */ |
| 3583 | /* optimise study_chunk() for TRIE */ |
| 3584 | minnext = study_chunk(pRExC_state, &scan, minlenp, |
| 3585 | &deltanext, (regnode *)nextbranch, &data_fake, |
| 3586 | stopparen, recursed_depth, NULL, f, depth+1, |
| 3587 | mutate_ok); |
| 3588 | } |
| 3589 | if (nextbranch && REGNODE_TYPE(OP(nextbranch))==BRANCH) |
| 3590 | nextbranch= regnext((regnode*)nextbranch); |
| 3591 | |
| 3592 | if (min1 > (SSize_t)(minnext + trie->minlen)) |
| 3593 | min1 = minnext + trie->minlen; |
| 3594 | if (deltanext == OPTIMIZE_INFTY) { |
| 3595 | is_inf = is_inf_internal = 1; |
| 3596 | max1 = OPTIMIZE_INFTY; |
| 3597 | } else if (max1 < (SSize_t)(minnext + deltanext + trie->maxlen)) |
| 3598 | max1 = minnext + deltanext + trie->maxlen; |
| 3599 | |
| 3600 | if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR)) |
| 3601 | pars++; |
| 3602 | if (data_fake.flags & SCF_SEEN_ACCEPT) { |
| 3603 | if ( stopmin > min + min1) |
| 3604 | stopmin = min + min1; |
| 3605 | flags &= ~SCF_DO_SUBSTR; |
| 3606 | if (data) |
| 3607 | data->flags |= SCF_SEEN_ACCEPT; |
| 3608 | } |
| 3609 | if (data) { |
| 3610 | if (data_fake.flags & SF_HAS_EVAL) |
| 3611 | data->flags |= SF_HAS_EVAL; |
| 3612 | data->whilem_c = data_fake.whilem_c; |
| 3613 | } |
| 3614 | if (flags & SCF_DO_STCLASS) |
| 3615 | ssc_or(pRExC_state, &accum, (regnode_charclass *) &this_class); |
| 3616 | } |
| 3617 | DEBUG_STUDYDATA("after JUMPTRIE", data, depth, is_inf, min, stopmin, delta); |
| 3618 | } |
| 3619 | if (flags & SCF_DO_SUBSTR) { |
| 3620 | data->pos_min += min1; |
| 3621 | data->pos_delta += max1 - min1; |
| 3622 | if (max1 != min1 || is_inf) |
| 3623 | data->cur_is_floating = 1; /* float */ |
| 3624 | } |
| 3625 | min += min1; |
| 3626 | if (delta != OPTIMIZE_INFTY) { |
| 3627 | if (OPTIMIZE_INFTY - (max1 - min1) >= delta) |
| 3628 | delta += max1 - min1; |
| 3629 | else |
| 3630 | delta = OPTIMIZE_INFTY; |
| 3631 | } |
| 3632 | if (flags & SCF_DO_STCLASS_OR) { |
| 3633 | ssc_or(pRExC_state, data->start_class, (regnode_charclass *) &accum); |
| 3634 | if (min1) { |
| 3635 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 3636 | flags &= ~SCF_DO_STCLASS; |
| 3637 | } |
| 3638 | } |
| 3639 | else if (flags & SCF_DO_STCLASS_AND) { |
| 3640 | if (min1) { |
| 3641 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) &accum); |
| 3642 | flags &= ~SCF_DO_STCLASS; |
| 3643 | } |
| 3644 | else { |
| 3645 | /* Switch to OR mode: cache the old value of |
| 3646 | * data->start_class */ |
| 3647 | INIT_AND_WITHP; |
| 3648 | StructCopy(data->start_class, and_withp, regnode_ssc); |
| 3649 | flags &= ~SCF_DO_STCLASS_AND; |
| 3650 | StructCopy(&accum, data->start_class, regnode_ssc); |
| 3651 | flags |= SCF_DO_STCLASS_OR; |
| 3652 | } |
| 3653 | } |
| 3654 | scan= tail; |
| 3655 | DEBUG_STUDYDATA("after TRIE study", data, depth, is_inf, min, stopmin, delta); |
| 3656 | continue; |
| 3657 | } |
| 3658 | #else |
| 3659 | else if (REGNODE_TYPE(OP(scan)) == TRIE) { |
| 3660 | reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ]; |
| 3661 | U8*bang=NULL; |
| 3662 | |
| 3663 | min += trie->minlen; |
| 3664 | delta += (trie->maxlen - trie->minlen); |
| 3665 | flags &= ~SCF_DO_STCLASS; /* xxx */ |
| 3666 | if (flags & SCF_DO_SUBSTR) { |
| 3667 | /* Cannot expect anything... */ |
| 3668 | scan_commit(pRExC_state, data, minlenp, is_inf); |
| 3669 | data->pos_min += trie->minlen; |
| 3670 | data->pos_delta += (trie->maxlen - trie->minlen); |
| 3671 | if (trie->maxlen != trie->minlen) |
| 3672 | data->cur_is_floating = 1; /* float */ |
| 3673 | } |
| 3674 | if (trie->jump) /* no more substrings -- for now /grr*/ |
| 3675 | flags &= ~SCF_DO_SUBSTR; |
| 3676 | } |
| 3677 | |
| 3678 | #endif /* old or new */ |
| 3679 | #endif /* TRIE_STUDY_OPT */ |
| 3680 | |
| 3681 | else if (OP(scan) == REGEX_SET) { |
| 3682 | Perl_croak(aTHX_ "panic: %s regnode should be resolved" |
| 3683 | " before optimization", REGNODE_NAME(REGEX_SET)); |
| 3684 | } |
| 3685 | |
| 3686 | /* Else: zero-length, ignore. */ |
| 3687 | scan = regnext(scan); |
| 3688 | } |
| 3689 | |
| 3690 | finish: |
| 3691 | if (frame) { |
| 3692 | /* we need to unwind recursion. */ |
| 3693 | depth = depth - 1; |
| 3694 | |
| 3695 | DEBUG_STUDYDATA("frame-end", data, depth, is_inf, min, stopmin, delta); |
| 3696 | DEBUG_PEEP("fend", scan, depth, flags); |
| 3697 | |
| 3698 | /* restore previous context */ |
| 3699 | last = frame->last_regnode; |
| 3700 | scan = frame->next_regnode; |
| 3701 | stopparen = frame->stopparen; |
| 3702 | recursed_depth = frame->prev_recursed_depth; |
| 3703 | |
| 3704 | RExC_frame_last = frame->prev_frame; |
| 3705 | frame = frame->this_prev_frame; |
| 3706 | goto fake_study_recurse; |
| 3707 | } |
| 3708 | |
| 3709 | assert(!frame); |
| 3710 | DEBUG_STUDYDATA("pre-fin", data, depth, is_inf, min, stopmin, delta); |
| 3711 | |
| 3712 | /* is this pattern infinite? Eg, consider /(a|b+)/ */ |
| 3713 | if (is_inf_internal) |
| 3714 | delta = OPTIMIZE_INFTY; |
| 3715 | |
| 3716 | /* deal with (*ACCEPT), Eg, consider /(foo(*ACCEPT)|bop)bar/ */ |
| 3717 | if (min > stopmin) { |
| 3718 | /* |
| 3719 | At this point 'min' represents the minimum length string we can |
| 3720 | match while *ignoring* the implication of ACCEPT, and 'delta' |
| 3721 | represents the difference between the minimum length and maximum |
| 3722 | length, and if the pattern matches an infinitely long string |
| 3723 | (consider the + and * quantifiers) then we use the special delta |
| 3724 | value of OPTIMIZE_INFTY to represent it. 'stopmin' is the |
| 3725 | minimum length that can be matched *and* accepted. |
| 3726 | |
| 3727 | A pattern is accepted when matching was successful *and* |
| 3728 | complete, and thus there is no further matching needing to be |
| 3729 | done, no backtracking to occur, etc. Prior to the introduction |
| 3730 | of ACCEPT the only opcode that signaled acceptance was the END |
| 3731 | opcode, which is always the very last opcode in a regex program. |
| 3732 | ACCEPT is thus conceptually an early successful return out of |
| 3733 | the matching process. stopmin starts out as OPTIMIZE_INFTY to |
| 3734 | represent "the entire pattern", and is ratched down to the |
| 3735 | "current min" if necessary when an ACCEPT opcode is encountered. |
| 3736 | |
| 3737 | Thus stopmin might be smaller than min if we saw an (*ACCEPT), |
| 3738 | and we now need to account for it in both min and delta. |
| 3739 | Consider that in a pattern /AB/ normally the min length it can |
| 3740 | match can be computed as min(A)+min(B). But (*ACCEPT) means |
| 3741 | that it might be something else, not even neccesarily min(A) at |
| 3742 | all. Consider |
| 3743 | |
| 3744 | A = /(foo(*ACCEPT)|x+)/ |
| 3745 | B = /whop/ |
| 3746 | AB = /(foo(*ACCEPT)|x+)whop/ |
| 3747 | |
| 3748 | The min for A is 1 for "x" and the delta for A is OPTIMIZE_INFTY |
| 3749 | for "xxxxx...", its stopmin is 3 for "foo". The min for B is 4 for |
| 3750 | "whop", and the delta of 0 as the pattern is of fixed length, the |
| 3751 | stopmin would be OPTIMIZE_INFTY as it does not contain an ACCEPT. |
| 3752 | When handling AB we expect to see a min of 5 for "xwhop", and a |
| 3753 | delta of OPTIMIZE_INFTY for "xxxxx...whop", and a stopmin of 3 |
| 3754 | for "foo". This should result in a final min of 3 for "foo", and |
| 3755 | a final delta of OPTIMIZE_INFTY for "xxxxx...whop". |
| 3756 | |
| 3757 | In something like /(dude(*ACCEPT)|irk)x{3,7}/ we would have a |
| 3758 | min of 6 for "irkxxx" and a delta of 4 for "irkxxxxxxx", and the |
| 3759 | stop min would be 4 for "dude". This should result in a final |
| 3760 | min of 4 for "dude", and a final delta of 6, for "irkxxxxxxx". |
| 3761 | |
| 3762 | When min is smaller than stopmin then we can ignore it. In the |
| 3763 | fragment /(x{10,20}(*ACCEPT)|a)b+/, we would have a min of 2, |
| 3764 | and a delta of OPTIMIZE_INFTY, and a stopmin of 10. Obviously |
| 3765 | the ACCEPT doesn't reduce the minimum length of the string that |
| 3766 | might be matched, nor affect the maximum length. |
| 3767 | |
| 3768 | In something like /foo(*ACCEPT)ba?r/ we would have a min of 5 |
| 3769 | for "foobr", a delta of 1 for "foobar", and a stopmin of 3 for |
| 3770 | "foo". We currently turn this into a min of 3 for "foo" and a |
| 3771 | delta of 3 for "foobar" even though technically "foobar" isn't |
| 3772 | possible. ACCEPT affects some aspects of the optimizer, like |
| 3773 | length computations and mandatory substring optimizations, but |
| 3774 | there are other optimzations this routine perfoms that are not |
| 3775 | affected and this compromise simplifies implementation. |
| 3776 | |
| 3777 | It might be helpful to consider that this C function is called |
| 3778 | recursively on the pattern in a bottom up fashion, and that the |
| 3779 | min returned by a nested call may be marked as coming from an |
| 3780 | ACCEPT, causing its callers to treat the returned min as a |
| 3781 | stopmin as the recursion unwinds. Thus a single ACCEPT can affect |
| 3782 | multiple calls into this function in different ways. |
| 3783 | */ |
| 3784 | |
| 3785 | if (OPTIMIZE_INFTY - delta >= min - stopmin) |
| 3786 | delta += min - stopmin; |
| 3787 | else |
| 3788 | delta = OPTIMIZE_INFTY; |
| 3789 | min = stopmin; |
| 3790 | } |
| 3791 | |
| 3792 | *scanp = scan; |
| 3793 | *deltap = delta; |
| 3794 | |
| 3795 | if (flags & SCF_DO_SUBSTR && is_inf) |
| 3796 | data->pos_delta = OPTIMIZE_INFTY - data->pos_min; |
| 3797 | if (is_par > (I32)U8_MAX) |
| 3798 | is_par = 0; |
| 3799 | if (is_par && pars==1 && data) { |
| 3800 | data->flags |= SF_IN_PAR; |
| 3801 | data->flags &= ~SF_HAS_PAR; |
| 3802 | } |
| 3803 | else if (pars && data) { |
| 3804 | data->flags |= SF_HAS_PAR; |
| 3805 | data->flags &= ~SF_IN_PAR; |
| 3806 | } |
| 3807 | if (flags & SCF_DO_STCLASS_OR) |
| 3808 | ssc_and(pRExC_state, data->start_class, (regnode_charclass *) and_withp); |
| 3809 | if (flags & SCF_TRIE_RESTUDY) |
| 3810 | data->flags |= SCF_TRIE_RESTUDY; |
| 3811 | |
| 3812 | |
| 3813 | if (!(RExC_seen & REG_UNBOUNDED_QUANTIFIER_SEEN)) { |
| 3814 | if (min > OPTIMIZE_INFTY - delta) |
| 3815 | RExC_maxlen = OPTIMIZE_INFTY; |
| 3816 | else if (RExC_maxlen < min + delta) |
| 3817 | RExC_maxlen = min + delta; |
| 3818 | } |
| 3819 | DEBUG_STUDYDATA("post-fin", data, depth, is_inf, min, stopmin, delta); |
| 3820 | return min; |
| 3821 | } |