regexp-macro-assembler-mips.cc revision 85b71799222b55eb5dd74ea26efe0c64ab655c8c
1// Copyright 2006-2010 the V8 project authors. All rights reserved. 2// Redistribution and use in source and binary forms, with or without 3// modification, are permitted provided that the following conditions are 4// met: 5// 6// * Redistributions of source code must retain the above copyright 7// notice, this list of conditions and the following disclaimer. 8// * Redistributions in binary form must reproduce the above 9// copyright notice, this list of conditions and the following 10// disclaimer in the documentation and/or other materials provided 11// with the distribution. 12// * Neither the name of Google Inc. nor the names of its 13// contributors may be used to endorse or promote products derived 14// from this software without specific prior written permission. 15// 16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28#include "v8.h" 29 30#if defined(V8_TARGET_ARCH_MIPS) 31 32#include "unicode.h" 33#include "log.h" 34#include "code-stubs.h" 35#include "regexp-stack.h" 36#include "macro-assembler.h" 37#include "regexp-macro-assembler.h" 38#include "mips/regexp-macro-assembler-mips.h" 39 40namespace v8 { 41namespace internal { 42 43#ifndef V8_INTERPRETED_REGEXP 44/* 45 * This assembler uses the following register assignment convention 46 * - t1 : Pointer to current code object (Code*) including heap object tag. 47 * - t2 : Current position in input, as negative offset from end of string. 48 * Please notice that this is the byte offset, not the character offset! 49 * - t3 : Currently loaded character. Must be loaded using 50 * LoadCurrentCharacter before using any of the dispatch methods. 51 * - t4 : points to tip of backtrack stack 52 * - t5 : Unused. 53 * - t6 : End of input (points to byte after last character in input). 54 * - fp : Frame pointer. Used to access arguments, local variables and 55 * RegExp registers. 56 * - sp : points to tip of C stack. 57 * 58 * The remaining registers are free for computations. 59 * Each call to a public method should retain this convention. 60 * 61 * The stack will have the following structure: 62 * 63 * - fp[56] direct_call (if 1, direct call from JavaScript code, 64 * if 0, call through the runtime system). 65 * - fp[52] stack_area_base (High end of the memory area to use as 66 * backtracking stack). 67 * - fp[48] int* capture_array (int[num_saved_registers_], for output). 68 * - fp[44] secondary link/return address used by native call. 69 * --- sp when called --- 70 * - fp[40] return address (lr). 71 * - fp[36] old frame pointer (r11). 72 * - fp[0..32] backup of registers s0..s7. 73 * --- frame pointer ---- 74 * - fp[-4] end of input (Address of end of string). 75 * - fp[-8] start of input (Address of first character in string). 76 * - fp[-12] start index (character index of start). 77 * - fp[-16] void* input_string (location of a handle containing the string). 78 * - fp[-20] Offset of location before start of input (effectively character 79 * position -1). Used to initialize capture registers to a 80 * non-position. 81 * - fp[-24] At start (if 1, we are starting at the start of the 82 * string, otherwise 0) 83 * - fp[-28] register 0 (Only positions must be stored in the first 84 * - register 1 num_saved_registers_ registers) 85 * - ... 86 * - register num_registers-1 87 * --- sp --- 88 * 89 * The first num_saved_registers_ registers are initialized to point to 90 * "character -1" in the string (i.e., char_size() bytes before the first 91 * character of the string). The remaining registers start out as garbage. 92 * 93 * The data up to the return address must be placed there by the calling 94 * code and the remaining arguments are passed in registers, e.g. by calling the 95 * code entry as cast to a function with the signature: 96 * int (*match)(String* input_string, 97 * int start_index, 98 * Address start, 99 * Address end, 100 * Address secondary_return_address, // Only used by native call. 101 * int* capture_output_array, 102 * byte* stack_area_base, 103 * bool direct_call = false) 104 * The call is performed by NativeRegExpMacroAssembler::Execute() 105 * (in regexp-macro-assembler.cc) via the CALL_GENERATED_REGEXP_CODE macro 106 * in mips/simulator-mips.h. 107 * When calling as a non-direct call (i.e., from C++ code), the return address 108 * area is overwritten with the ra register by the RegExp code. When doing a 109 * direct call from generated code, the return address is placed there by 110 * the calling code, as in a normal exit frame. 111 */ 112 113#define __ ACCESS_MASM(masm_) 114 115RegExpMacroAssemblerMIPS::RegExpMacroAssemblerMIPS( 116 Mode mode, 117 int registers_to_save) 118 : masm_(new MacroAssembler(Isolate::Current(), NULL, kRegExpCodeSize)), 119 mode_(mode), 120 num_registers_(registers_to_save), 121 num_saved_registers_(registers_to_save), 122 entry_label_(), 123 start_label_(), 124 success_label_(), 125 backtrack_label_(), 126 exit_label_(), 127 internal_failure_label_() { 128 ASSERT_EQ(0, registers_to_save % 2); 129 __ jmp(&entry_label_); // We'll write the entry code later. 130 // If the code gets too big or corrupted, an internal exception will be 131 // raised, and we will exit right away. 132 __ bind(&internal_failure_label_); 133 __ li(v0, Operand(FAILURE)); 134 __ Ret(); 135 __ bind(&start_label_); // And then continue from here. 136} 137 138 139RegExpMacroAssemblerMIPS::~RegExpMacroAssemblerMIPS() { 140 delete masm_; 141 // Unuse labels in case we throw away the assembler without calling GetCode. 142 entry_label_.Unuse(); 143 start_label_.Unuse(); 144 success_label_.Unuse(); 145 backtrack_label_.Unuse(); 146 exit_label_.Unuse(); 147 check_preempt_label_.Unuse(); 148 stack_overflow_label_.Unuse(); 149 internal_failure_label_.Unuse(); 150} 151 152 153int RegExpMacroAssemblerMIPS::stack_limit_slack() { 154 return RegExpStack::kStackLimitSlack; 155} 156 157 158void RegExpMacroAssemblerMIPS::AdvanceCurrentPosition(int by) { 159 if (by != 0) { 160 __ Addu(current_input_offset(), 161 current_input_offset(), Operand(by * char_size())); 162 } 163} 164 165 166void RegExpMacroAssemblerMIPS::AdvanceRegister(int reg, int by) { 167 ASSERT(reg >= 0); 168 ASSERT(reg < num_registers_); 169 if (by != 0) { 170 __ lw(a0, register_location(reg)); 171 __ Addu(a0, a0, Operand(by)); 172 __ sw(a0, register_location(reg)); 173 } 174} 175 176 177void RegExpMacroAssemblerMIPS::Backtrack() { 178 CheckPreemption(); 179 // Pop Code* offset from backtrack stack, add Code* and jump to location. 180 Pop(a0); 181 __ Addu(a0, a0, code_pointer()); 182 __ Jump(a0); 183} 184 185 186void RegExpMacroAssemblerMIPS::Bind(Label* label) { 187 __ bind(label); 188} 189 190 191void RegExpMacroAssemblerMIPS::CheckCharacter(uint32_t c, Label* on_equal) { 192 BranchOrBacktrack(on_equal, eq, current_character(), Operand(c)); 193} 194 195 196void RegExpMacroAssemblerMIPS::CheckCharacterGT(uc16 limit, Label* on_greater) { 197 BranchOrBacktrack(on_greater, gt, current_character(), Operand(limit)); 198} 199 200 201void RegExpMacroAssemblerMIPS::CheckAtStart(Label* on_at_start) { 202 Label not_at_start; 203 // Did we start the match at the start of the string at all? 204 __ lw(a0, MemOperand(frame_pointer(), kAtStart)); 205 BranchOrBacktrack(¬_at_start, eq, a0, Operand(zero_reg)); 206 207 // If we did, are we still at the start of the input? 208 __ lw(a1, MemOperand(frame_pointer(), kInputStart)); 209 __ Addu(a0, end_of_input_address(), Operand(current_input_offset())); 210 BranchOrBacktrack(on_at_start, eq, a0, Operand(a1)); 211 __ bind(¬_at_start); 212} 213 214 215void RegExpMacroAssemblerMIPS::CheckNotAtStart(Label* on_not_at_start) { 216 // Did we start the match at the start of the string at all? 217 __ lw(a0, MemOperand(frame_pointer(), kAtStart)); 218 BranchOrBacktrack(on_not_at_start, eq, a0, Operand(zero_reg)); 219 // If we did, are we still at the start of the input? 220 __ lw(a1, MemOperand(frame_pointer(), kInputStart)); 221 __ Addu(a0, end_of_input_address(), Operand(current_input_offset())); 222 BranchOrBacktrack(on_not_at_start, ne, a0, Operand(a1)); 223} 224 225 226void RegExpMacroAssemblerMIPS::CheckCharacterLT(uc16 limit, Label* on_less) { 227 BranchOrBacktrack(on_less, lt, current_character(), Operand(limit)); 228} 229 230 231void RegExpMacroAssemblerMIPS::CheckCharacters(Vector<const uc16> str, 232 int cp_offset, 233 Label* on_failure, 234 bool check_end_of_string) { 235 if (on_failure == NULL) { 236 // Instead of inlining a backtrack for each test, (re)use the global 237 // backtrack target. 238 on_failure = &backtrack_label_; 239 } 240 241 if (check_end_of_string) { 242 // Is last character of required match inside string. 243 CheckPosition(cp_offset + str.length() - 1, on_failure); 244 } 245 246 __ Addu(a0, end_of_input_address(), Operand(current_input_offset())); 247 if (cp_offset != 0) { 248 int byte_offset = cp_offset * char_size(); 249 __ Addu(a0, a0, Operand(byte_offset)); 250 } 251 252 // a0 : Address of characters to match against str. 253 int stored_high_byte = 0; 254 for (int i = 0; i < str.length(); i++) { 255 if (mode_ == ASCII) { 256 __ lbu(a1, MemOperand(a0, 0)); 257 __ addiu(a0, a0, char_size()); 258 ASSERT(str[i] <= String::kMaxAsciiCharCode); 259 BranchOrBacktrack(on_failure, ne, a1, Operand(str[i])); 260 } else { 261 __ lhu(a1, MemOperand(a0, 0)); 262 __ addiu(a0, a0, char_size()); 263 uc16 match_char = str[i]; 264 int match_high_byte = (match_char >> 8); 265 if (match_high_byte == 0) { 266 BranchOrBacktrack(on_failure, ne, a1, Operand(str[i])); 267 } else { 268 if (match_high_byte != stored_high_byte) { 269 __ li(a2, Operand(match_high_byte)); 270 stored_high_byte = match_high_byte; 271 } 272 __ Addu(a3, a2, Operand(match_char & 0xff)); 273 BranchOrBacktrack(on_failure, ne, a1, Operand(a3)); 274 } 275 } 276 } 277} 278 279 280void RegExpMacroAssemblerMIPS::CheckGreedyLoop(Label* on_equal) { 281 Label backtrack_non_equal; 282 __ lw(a0, MemOperand(backtrack_stackpointer(), 0)); 283 __ Branch(&backtrack_non_equal, ne, current_input_offset(), Operand(a0)); 284 __ Addu(backtrack_stackpointer(), 285 backtrack_stackpointer(), 286 Operand(kPointerSize)); 287 __ bind(&backtrack_non_equal); 288 BranchOrBacktrack(on_equal, eq, current_input_offset(), Operand(a0)); 289} 290 291 292void RegExpMacroAssemblerMIPS::CheckNotBackReferenceIgnoreCase( 293 int start_reg, 294 Label* on_no_match) { 295 Label fallthrough; 296 __ lw(a0, register_location(start_reg)); // Index of start of capture. 297 __ lw(a1, register_location(start_reg + 1)); // Index of end of capture. 298 __ Subu(a1, a1, a0); // Length of capture. 299 300 // If length is zero, either the capture is empty or it is not participating. 301 // In either case succeed immediately. 302 __ Branch(&fallthrough, eq, a1, Operand(zero_reg)); 303 304 __ Addu(t5, a1, current_input_offset()); 305 // Check that there are enough characters left in the input. 306 BranchOrBacktrack(on_no_match, gt, t5, Operand(zero_reg)); 307 308 if (mode_ == ASCII) { 309 Label success; 310 Label fail; 311 Label loop_check; 312 313 // a0 - offset of start of capture. 314 // a1 - length of capture. 315 __ Addu(a0, a0, Operand(end_of_input_address())); 316 __ Addu(a2, end_of_input_address(), Operand(current_input_offset())); 317 __ Addu(a1, a0, Operand(a1)); 318 319 // a0 - Address of start of capture. 320 // a1 - Address of end of capture. 321 // a2 - Address of current input position. 322 323 Label loop; 324 __ bind(&loop); 325 __ lbu(a3, MemOperand(a0, 0)); 326 __ addiu(a0, a0, char_size()); 327 __ lbu(t0, MemOperand(a2, 0)); 328 __ addiu(a2, a2, char_size()); 329 330 __ Branch(&loop_check, eq, t0, Operand(a3)); 331 332 // Mismatch, try case-insensitive match (converting letters to lower-case). 333 __ Or(a3, a3, Operand(0x20)); // Convert capture character to lower-case. 334 __ Or(t0, t0, Operand(0x20)); // Also convert input character. 335 __ Branch(&fail, ne, t0, Operand(a3)); 336 __ Subu(a3, a3, Operand('a')); 337 __ Branch(&fail, hi, a3, Operand('z' - 'a')); // Is a3 a lowercase letter? 338 339 __ bind(&loop_check); 340 __ Branch(&loop, lt, a0, Operand(a1)); 341 __ jmp(&success); 342 343 __ bind(&fail); 344 GoTo(on_no_match); 345 346 __ bind(&success); 347 // Compute new value of character position after the matched part. 348 __ Subu(current_input_offset(), a2, end_of_input_address()); 349 } else { 350 ASSERT(mode_ == UC16); 351 // Put regexp engine registers on stack. 352 RegList regexp_registers_to_retain = current_input_offset().bit() | 353 current_character().bit() | backtrack_stackpointer().bit(); 354 __ MultiPush(regexp_registers_to_retain); 355 356 int argument_count = 4; 357 __ PrepareCallCFunction(argument_count, a2); 358 359 // a0 - offset of start of capture. 360 // a1 - length of capture. 361 362 // Put arguments into arguments registers. 363 // Parameters are 364 // a0: Address byte_offset1 - Address captured substring's start. 365 // a1: Address byte_offset2 - Address of current character position. 366 // a2: size_t byte_length - length of capture in bytes(!). 367 // a3: Isolate* isolate. 368 369 // Address of start of capture. 370 __ Addu(a0, a0, Operand(end_of_input_address())); 371 // Length of capture. 372 __ mov(a2, a1); 373 // Save length in callee-save register for use on return. 374 __ mov(s3, a1); 375 // Address of current input position. 376 __ Addu(a1, current_input_offset(), Operand(end_of_input_address())); 377 // Isolate. 378 __ li(a3, Operand(ExternalReference::isolate_address())); 379 380 ExternalReference function = 381 ExternalReference::re_case_insensitive_compare_uc16(masm_->isolate()); 382 __ CallCFunction(function, argument_count); 383 384 // Restore regexp engine registers. 385 __ MultiPop(regexp_registers_to_retain); 386 __ li(code_pointer(), Operand(masm_->CodeObject())); 387 __ lw(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); 388 389 // Check if function returned non-zero for success or zero for failure. 390 BranchOrBacktrack(on_no_match, eq, v0, Operand(zero_reg)); 391 // On success, increment position by length of capture. 392 __ Addu(current_input_offset(), current_input_offset(), Operand(s3)); 393 } 394 395 __ bind(&fallthrough); 396} 397 398 399void RegExpMacroAssemblerMIPS::CheckNotBackReference( 400 int start_reg, 401 Label* on_no_match) { 402 Label fallthrough; 403 Label success; 404 405 // Find length of back-referenced capture. 406 __ lw(a0, register_location(start_reg)); 407 __ lw(a1, register_location(start_reg + 1)); 408 __ Subu(a1, a1, a0); // Length to check. 409 // Succeed on empty capture (including no capture). 410 __ Branch(&fallthrough, eq, a1, Operand(zero_reg)); 411 412 __ Addu(t5, a1, current_input_offset()); 413 // Check that there are enough characters left in the input. 414 BranchOrBacktrack(on_no_match, gt, t5, Operand(zero_reg)); 415 416 // Compute pointers to match string and capture string. 417 __ Addu(a0, a0, Operand(end_of_input_address())); 418 __ Addu(a2, end_of_input_address(), Operand(current_input_offset())); 419 __ Addu(a1, a1, Operand(a0)); 420 421 Label loop; 422 __ bind(&loop); 423 if (mode_ == ASCII) { 424 __ lbu(a3, MemOperand(a0, 0)); 425 __ addiu(a0, a0, char_size()); 426 __ lbu(t0, MemOperand(a2, 0)); 427 __ addiu(a2, a2, char_size()); 428 } else { 429 ASSERT(mode_ == UC16); 430 __ lhu(a3, MemOperand(a0, 0)); 431 __ addiu(a0, a0, char_size()); 432 __ lhu(t0, MemOperand(a2, 0)); 433 __ addiu(a2, a2, char_size()); 434 } 435 BranchOrBacktrack(on_no_match, ne, a3, Operand(t0)); 436 __ Branch(&loop, lt, a0, Operand(a1)); 437 438 // Move current character position to position after match. 439 __ Subu(current_input_offset(), a2, end_of_input_address()); 440 __ bind(&fallthrough); 441} 442 443 444void RegExpMacroAssemblerMIPS::CheckNotRegistersEqual(int reg1, 445 int reg2, 446 Label* on_not_equal) { 447 UNIMPLEMENTED_MIPS(); 448} 449 450 451void RegExpMacroAssemblerMIPS::CheckNotCharacter(uint32_t c, 452 Label* on_not_equal) { 453 BranchOrBacktrack(on_not_equal, ne, current_character(), Operand(c)); 454} 455 456 457void RegExpMacroAssemblerMIPS::CheckCharacterAfterAnd(uint32_t c, 458 uint32_t mask, 459 Label* on_equal) { 460 __ And(a0, current_character(), Operand(mask)); 461 BranchOrBacktrack(on_equal, eq, a0, Operand(c)); 462} 463 464 465void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterAnd(uint32_t c, 466 uint32_t mask, 467 Label* on_not_equal) { 468 __ And(a0, current_character(), Operand(mask)); 469 BranchOrBacktrack(on_not_equal, ne, a0, Operand(c)); 470} 471 472 473void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterMinusAnd( 474 uc16 c, 475 uc16 minus, 476 uc16 mask, 477 Label* on_not_equal) { 478 UNIMPLEMENTED_MIPS(); 479} 480 481 482bool RegExpMacroAssemblerMIPS::CheckSpecialCharacterClass(uc16 type, 483 Label* on_no_match) { 484 // Range checks (c in min..max) are generally implemented by an unsigned 485 // (c - min) <= (max - min) check. 486 switch (type) { 487 case 's': 488 // Match space-characters. 489 if (mode_ == ASCII) { 490 // ASCII space characters are '\t'..'\r' and ' '. 491 Label success; 492 __ Branch(&success, eq, current_character(), Operand(' ')); 493 // Check range 0x09..0x0d. 494 __ Subu(a0, current_character(), Operand('\t')); 495 BranchOrBacktrack(on_no_match, hi, a0, Operand('\r' - '\t')); 496 __ bind(&success); 497 return true; 498 } 499 return false; 500 case 'S': 501 // Match non-space characters. 502 if (mode_ == ASCII) { 503 // ASCII space characters are '\t'..'\r' and ' '. 504 BranchOrBacktrack(on_no_match, eq, current_character(), Operand(' ')); 505 __ Subu(a0, current_character(), Operand('\t')); 506 BranchOrBacktrack(on_no_match, ls, a0, Operand('\r' - '\t')); 507 return true; 508 } 509 return false; 510 case 'd': 511 // Match ASCII digits ('0'..'9'). 512 __ Subu(a0, current_character(), Operand('0')); 513 BranchOrBacktrack(on_no_match, hi, a0, Operand('9' - '0')); 514 return true; 515 case 'D': 516 // Match non ASCII-digits. 517 __ Subu(a0, current_character(), Operand('0')); 518 BranchOrBacktrack(on_no_match, ls, a0, Operand('9' - '0')); 519 return true; 520 case '.': { 521 // Match non-newlines (not 0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029). 522 __ Xor(a0, current_character(), Operand(0x01)); 523 // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c. 524 __ Subu(a0, a0, Operand(0x0b)); 525 BranchOrBacktrack(on_no_match, ls, a0, Operand(0x0c - 0x0b)); 526 if (mode_ == UC16) { 527 // Compare original value to 0x2028 and 0x2029, using the already 528 // computed (current_char ^ 0x01 - 0x0b). I.e., check for 529 // 0x201d (0x2028 - 0x0b) or 0x201e. 530 __ Subu(a0, a0, Operand(0x2028 - 0x0b)); 531 BranchOrBacktrack(on_no_match, ls, a0, Operand(1)); 532 } 533 return true; 534 } 535 case 'n': { 536 // Match newlines (0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029). 537 __ Xor(a0, current_character(), Operand(0x01)); 538 // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c. 539 __ Subu(a0, a0, Operand(0x0b)); 540 if (mode_ == ASCII) { 541 BranchOrBacktrack(on_no_match, hi, a0, Operand(0x0c - 0x0b)); 542 } else { 543 Label done; 544 BranchOrBacktrack(&done, ls, a0, Operand(0x0c - 0x0b)); 545 // Compare original value to 0x2028 and 0x2029, using the already 546 // computed (current_char ^ 0x01 - 0x0b). I.e., check for 547 // 0x201d (0x2028 - 0x0b) or 0x201e. 548 __ Subu(a0, a0, Operand(0x2028 - 0x0b)); 549 BranchOrBacktrack(on_no_match, hi, a0, Operand(1)); 550 __ bind(&done); 551 } 552 return true; 553 } 554 case 'w': { 555 if (mode_ != ASCII) { 556 // Table is 128 entries, so all ASCII characters can be tested. 557 BranchOrBacktrack(on_no_match, hi, current_character(), Operand('z')); 558 } 559 ExternalReference map = ExternalReference::re_word_character_map(); 560 __ li(a0, Operand(map)); 561 __ Addu(a0, a0, current_character()); 562 __ lbu(a0, MemOperand(a0, 0)); 563 BranchOrBacktrack(on_no_match, eq, a0, Operand(zero_reg)); 564 return true; 565 } 566 case 'W': { 567 Label done; 568 if (mode_ != ASCII) { 569 // Table is 128 entries, so all ASCII characters can be tested. 570 __ Branch(&done, hi, current_character(), Operand('z')); 571 } 572 ExternalReference map = ExternalReference::re_word_character_map(); 573 __ li(a0, Operand(map)); 574 __ Addu(a0, a0, current_character()); 575 __ lbu(a0, MemOperand(a0, 0)); 576 BranchOrBacktrack(on_no_match, ne, a0, Operand(zero_reg)); 577 if (mode_ != ASCII) { 578 __ bind(&done); 579 } 580 return true; 581 } 582 case '*': 583 // Match any character. 584 return true; 585 // No custom implementation (yet): s(UC16), S(UC16). 586 default: 587 return false; 588 } 589} 590 591 592void RegExpMacroAssemblerMIPS::Fail() { 593 __ li(v0, Operand(FAILURE)); 594 __ jmp(&exit_label_); 595} 596 597 598Handle<HeapObject> RegExpMacroAssemblerMIPS::GetCode(Handle<String> source) { 599 if (masm_->has_exception()) { 600 // If the code gets corrupted due to long regular expressions and lack of 601 // space on trampolines, an internal exception flag is set. If this case 602 // is detected, we will jump into exit sequence right away. 603 __ bind_to(&entry_label_, internal_failure_label_.pos()); 604 } else { 605 // Finalize code - write the entry point code now we know how many 606 // registers we need. 607 608 // Entry code: 609 __ bind(&entry_label_); 610 // Push arguments 611 // Save callee-save registers. 612 // Start new stack frame. 613 // Store link register in existing stack-cell. 614 // Order here should correspond to order of offset constants in header file. 615 RegList registers_to_retain = s0.bit() | s1.bit() | s2.bit() | 616 s3.bit() | s4.bit() | s5.bit() | s6.bit() | s7.bit() | fp.bit(); 617 RegList argument_registers = a0.bit() | a1.bit() | a2.bit() | a3.bit(); 618 __ MultiPush(argument_registers | registers_to_retain | ra.bit()); 619 // Set frame pointer in space for it if this is not a direct call 620 // from generated code. 621 __ Addu(frame_pointer(), sp, Operand(4 * kPointerSize)); 622 __ push(a0); // Make room for "position - 1" constant (value irrelevant). 623 __ push(a0); // Make room for "at start" constant (value irrelevant). 624 625 // Check if we have space on the stack for registers. 626 Label stack_limit_hit; 627 Label stack_ok; 628 629 ExternalReference stack_limit = 630 ExternalReference::address_of_stack_limit(masm_->isolate()); 631 __ li(a0, Operand(stack_limit)); 632 __ lw(a0, MemOperand(a0)); 633 __ Subu(a0, sp, a0); 634 // Handle it if the stack pointer is already below the stack limit. 635 __ Branch(&stack_limit_hit, le, a0, Operand(zero_reg)); 636 // Check if there is room for the variable number of registers above 637 // the stack limit. 638 __ Branch(&stack_ok, hs, a0, Operand(num_registers_ * kPointerSize)); 639 // Exit with OutOfMemory exception. There is not enough space on the stack 640 // for our working registers. 641 __ li(v0, Operand(EXCEPTION)); 642 __ jmp(&exit_label_); 643 644 __ bind(&stack_limit_hit); 645 CallCheckStackGuardState(a0); 646 // If returned value is non-zero, we exit with the returned value as result. 647 __ Branch(&exit_label_, ne, v0, Operand(zero_reg)); 648 649 __ bind(&stack_ok); 650 // Allocate space on stack for registers. 651 __ Subu(sp, sp, Operand(num_registers_ * kPointerSize)); 652 // Load string end. 653 __ lw(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); 654 // Load input start. 655 __ lw(a0, MemOperand(frame_pointer(), kInputStart)); 656 // Find negative length (offset of start relative to end). 657 __ Subu(current_input_offset(), a0, end_of_input_address()); 658 // Set a0 to address of char before start of the input string 659 // (effectively string position -1). 660 __ lw(a1, MemOperand(frame_pointer(), kStartIndex)); 661 __ Subu(a0, current_input_offset(), Operand(char_size())); 662 __ sll(t5, a1, (mode_ == UC16) ? 1 : 0); 663 __ Subu(a0, a0, t5); 664 // Store this value in a local variable, for use when clearing 665 // position registers. 666 __ sw(a0, MemOperand(frame_pointer(), kInputStartMinusOne)); 667 668 // Determine whether the start index is zero, that is at the start of the 669 // string, and store that value in a local variable. 670 __ mov(t5, a1); 671 __ li(a1, Operand(1)); 672 __ movn(a1, zero_reg, t5); 673 __ sw(a1, MemOperand(frame_pointer(), kAtStart)); 674 675 if (num_saved_registers_ > 0) { // Always is, if generated from a regexp. 676 // Fill saved registers with initial value = start offset - 1. 677 678 // Address of register 0. 679 __ Addu(a1, frame_pointer(), Operand(kRegisterZero)); 680 __ li(a2, Operand(num_saved_registers_)); 681 Label init_loop; 682 __ bind(&init_loop); 683 __ sw(a0, MemOperand(a1)); 684 __ Addu(a1, a1, Operand(-kPointerSize)); 685 __ Subu(a2, a2, Operand(1)); 686 __ Branch(&init_loop, ne, a2, Operand(zero_reg)); 687 } 688 689 // Initialize backtrack stack pointer. 690 __ lw(backtrack_stackpointer(), MemOperand(frame_pointer(), kStackHighEnd)); 691 // Initialize code pointer register 692 __ li(code_pointer(), Operand(masm_->CodeObject())); 693 // Load previous char as initial value of current character register. 694 Label at_start; 695 __ lw(a0, MemOperand(frame_pointer(), kAtStart)); 696 __ Branch(&at_start, ne, a0, Operand(zero_reg)); 697 LoadCurrentCharacterUnchecked(-1, 1); // Load previous char. 698 __ jmp(&start_label_); 699 __ bind(&at_start); 700 __ li(current_character(), Operand('\n')); 701 __ jmp(&start_label_); 702 703 704 // Exit code: 705 if (success_label_.is_linked()) { 706 // Save captures when successful. 707 __ bind(&success_label_); 708 if (num_saved_registers_ > 0) { 709 // Copy captures to output. 710 __ lw(a1, MemOperand(frame_pointer(), kInputStart)); 711 __ lw(a0, MemOperand(frame_pointer(), kRegisterOutput)); 712 __ lw(a2, MemOperand(frame_pointer(), kStartIndex)); 713 __ Subu(a1, end_of_input_address(), a1); 714 // a1 is length of input in bytes. 715 if (mode_ == UC16) { 716 __ srl(a1, a1, 1); 717 } 718 // a1 is length of input in characters. 719 __ Addu(a1, a1, Operand(a2)); 720 // a1 is length of string in characters. 721 722 ASSERT_EQ(0, num_saved_registers_ % 2); 723 // Always an even number of capture registers. This allows us to 724 // unroll the loop once to add an operation between a load of a register 725 // and the following use of that register. 726 for (int i = 0; i < num_saved_registers_; i += 2) { 727 __ lw(a2, register_location(i)); 728 __ lw(a3, register_location(i + 1)); 729 if (mode_ == UC16) { 730 __ sra(a2, a2, 1); 731 __ Addu(a2, a2, a1); 732 __ sra(a3, a3, 1); 733 __ Addu(a3, a3, a1); 734 } else { 735 __ Addu(a2, a1, Operand(a2)); 736 __ Addu(a3, a1, Operand(a3)); 737 } 738 __ sw(a2, MemOperand(a0)); 739 __ Addu(a0, a0, kPointerSize); 740 __ sw(a3, MemOperand(a0)); 741 __ Addu(a0, a0, kPointerSize); 742 } 743 } 744 __ li(v0, Operand(SUCCESS)); 745 } 746 // Exit and return v0. 747 __ bind(&exit_label_); 748 // Skip sp past regexp registers and local variables.. 749 __ mov(sp, frame_pointer()); 750 // Restore registers s0..s7 and return (restoring ra to pc). 751 __ MultiPop(registers_to_retain | ra.bit()); 752 __ Ret(); 753 754 // Backtrack code (branch target for conditional backtracks). 755 if (backtrack_label_.is_linked()) { 756 __ bind(&backtrack_label_); 757 Backtrack(); 758 } 759 760 Label exit_with_exception; 761 762 // Preempt-code. 763 if (check_preempt_label_.is_linked()) { 764 SafeCallTarget(&check_preempt_label_); 765 // Put regexp engine registers on stack. 766 RegList regexp_registers_to_retain = current_input_offset().bit() | 767 current_character().bit() | backtrack_stackpointer().bit(); 768 __ MultiPush(regexp_registers_to_retain); 769 CallCheckStackGuardState(a0); 770 __ MultiPop(regexp_registers_to_retain); 771 // If returning non-zero, we should end execution with the given 772 // result as return value. 773 __ Branch(&exit_label_, ne, v0, Operand(zero_reg)); 774 775 // String might have moved: Reload end of string from frame. 776 __ lw(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); 777 __ li(code_pointer(), Operand(masm_->CodeObject())); 778 SafeReturn(); 779 } 780 781 // Backtrack stack overflow code. 782 if (stack_overflow_label_.is_linked()) { 783 SafeCallTarget(&stack_overflow_label_); 784 // Reached if the backtrack-stack limit has been hit. 785 // Put regexp engine registers on stack first. 786 RegList regexp_registers = current_input_offset().bit() | 787 current_character().bit(); 788 __ MultiPush(regexp_registers); 789 Label grow_failed; 790 // Call GrowStack(backtrack_stackpointer(), &stack_base) 791 static const int num_arguments = 3; 792 __ PrepareCallCFunction(num_arguments, a0); 793 __ mov(a0, backtrack_stackpointer()); 794 __ Addu(a1, frame_pointer(), Operand(kStackHighEnd)); 795 __ li(a2, Operand(ExternalReference::isolate_address())); 796 ExternalReference grow_stack = 797 ExternalReference::re_grow_stack(masm_->isolate()); 798 __ CallCFunction(grow_stack, num_arguments); 799 // Restore regexp registers. 800 __ MultiPop(regexp_registers); 801 // If return NULL, we have failed to grow the stack, and 802 // must exit with a stack-overflow exception. 803 __ Branch(&exit_with_exception, eq, v0, Operand(zero_reg)); 804 // Otherwise use return value as new stack pointer. 805 __ mov(backtrack_stackpointer(), v0); 806 // Restore saved registers and continue. 807 __ li(code_pointer(), Operand(masm_->CodeObject())); 808 __ lw(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); 809 SafeReturn(); 810 } 811 812 if (exit_with_exception.is_linked()) { 813 // If any of the code above needed to exit with an exception. 814 __ bind(&exit_with_exception); 815 // Exit with Result EXCEPTION(-1) to signal thrown exception. 816 __ li(v0, Operand(EXCEPTION)); 817 __ jmp(&exit_label_); 818 } 819 } 820 821 CodeDesc code_desc; 822 masm_->GetCode(&code_desc); 823 Handle<Code> code = FACTORY->NewCode(code_desc, 824 Code::ComputeFlags(Code::REGEXP), 825 masm_->CodeObject()); 826 LOG(Isolate::Current(), RegExpCodeCreateEvent(*code, *source)); 827 return Handle<HeapObject>::cast(code); 828} 829 830 831void RegExpMacroAssemblerMIPS::GoTo(Label* to) { 832 if (to == NULL) { 833 Backtrack(); 834 return; 835 } 836 __ jmp(to); 837 return; 838} 839 840 841void RegExpMacroAssemblerMIPS::IfRegisterGE(int reg, 842 int comparand, 843 Label* if_ge) { 844 __ lw(a0, register_location(reg)); 845 BranchOrBacktrack(if_ge, ge, a0, Operand(comparand)); 846} 847 848 849void RegExpMacroAssemblerMIPS::IfRegisterLT(int reg, 850 int comparand, 851 Label* if_lt) { 852 __ lw(a0, register_location(reg)); 853 BranchOrBacktrack(if_lt, lt, a0, Operand(comparand)); 854} 855 856 857void RegExpMacroAssemblerMIPS::IfRegisterEqPos(int reg, 858 Label* if_eq) { 859 __ lw(a0, register_location(reg)); 860 BranchOrBacktrack(if_eq, eq, a0, Operand(current_input_offset())); 861} 862 863 864RegExpMacroAssembler::IrregexpImplementation 865 RegExpMacroAssemblerMIPS::Implementation() { 866 return kMIPSImplementation; 867} 868 869 870void RegExpMacroAssemblerMIPS::LoadCurrentCharacter(int cp_offset, 871 Label* on_end_of_input, 872 bool check_bounds, 873 int characters) { 874 ASSERT(cp_offset >= -1); // ^ and \b can look behind one character. 875 ASSERT(cp_offset < (1<<30)); // Be sane! (And ensure negation works). 876 if (check_bounds) { 877 CheckPosition(cp_offset + characters - 1, on_end_of_input); 878 } 879 LoadCurrentCharacterUnchecked(cp_offset, characters); 880} 881 882 883void RegExpMacroAssemblerMIPS::PopCurrentPosition() { 884 Pop(current_input_offset()); 885} 886 887 888void RegExpMacroAssemblerMIPS::PopRegister(int register_index) { 889 Pop(a0); 890 __ sw(a0, register_location(register_index)); 891} 892 893 894void RegExpMacroAssemblerMIPS::PushBacktrack(Label* label) { 895 if (label->is_bound()) { 896 int target = label->pos(); 897 __ li(a0, Operand(target + Code::kHeaderSize - kHeapObjectTag)); 898 } else { 899 Label after_constant; 900 __ Branch(&after_constant); 901 int offset = masm_->pc_offset(); 902 int cp_offset = offset + Code::kHeaderSize - kHeapObjectTag; 903 __ emit(0); 904 masm_->label_at_put(label, offset); 905 __ bind(&after_constant); 906 if (is_int16(cp_offset)) { 907 __ lw(a0, MemOperand(code_pointer(), cp_offset)); 908 } else { 909 __ Addu(a0, code_pointer(), cp_offset); 910 __ lw(a0, MemOperand(a0, 0)); 911 } 912 } 913 Push(a0); 914 CheckStackLimit(); 915} 916 917 918void RegExpMacroAssemblerMIPS::PushCurrentPosition() { 919 Push(current_input_offset()); 920} 921 922 923void RegExpMacroAssemblerMIPS::PushRegister(int register_index, 924 StackCheckFlag check_stack_limit) { 925 __ lw(a0, register_location(register_index)); 926 Push(a0); 927 if (check_stack_limit) CheckStackLimit(); 928} 929 930 931void RegExpMacroAssemblerMIPS::ReadCurrentPositionFromRegister(int reg) { 932 __ lw(current_input_offset(), register_location(reg)); 933} 934 935 936void RegExpMacroAssemblerMIPS::ReadStackPointerFromRegister(int reg) { 937 __ lw(backtrack_stackpointer(), register_location(reg)); 938 __ lw(a0, MemOperand(frame_pointer(), kStackHighEnd)); 939 __ Addu(backtrack_stackpointer(), backtrack_stackpointer(), Operand(a0)); 940} 941 942 943void RegExpMacroAssemblerMIPS::SetCurrentPositionFromEnd(int by) { 944 Label after_position; 945 __ Branch(&after_position, 946 ge, 947 current_input_offset(), 948 Operand(-by * char_size())); 949 __ li(current_input_offset(), -by * char_size()); 950 // On RegExp code entry (where this operation is used), the character before 951 // the current position is expected to be already loaded. 952 // We have advanced the position, so it's safe to read backwards. 953 LoadCurrentCharacterUnchecked(-1, 1); 954 __ bind(&after_position); 955} 956 957 958void RegExpMacroAssemblerMIPS::SetRegister(int register_index, int to) { 959 ASSERT(register_index >= num_saved_registers_); // Reserved for positions! 960 __ li(a0, Operand(to)); 961 __ sw(a0, register_location(register_index)); 962} 963 964 965void RegExpMacroAssemblerMIPS::Succeed() { 966 __ jmp(&success_label_); 967} 968 969 970void RegExpMacroAssemblerMIPS::WriteCurrentPositionToRegister(int reg, 971 int cp_offset) { 972 if (cp_offset == 0) { 973 __ sw(current_input_offset(), register_location(reg)); 974 } else { 975 __ Addu(a0, current_input_offset(), Operand(cp_offset * char_size())); 976 __ sw(a0, register_location(reg)); 977 } 978} 979 980 981void RegExpMacroAssemblerMIPS::ClearRegisters(int reg_from, int reg_to) { 982 ASSERT(reg_from <= reg_to); 983 __ lw(a0, MemOperand(frame_pointer(), kInputStartMinusOne)); 984 for (int reg = reg_from; reg <= reg_to; reg++) { 985 __ sw(a0, register_location(reg)); 986 } 987} 988 989 990void RegExpMacroAssemblerMIPS::WriteStackPointerToRegister(int reg) { 991 __ lw(a1, MemOperand(frame_pointer(), kStackHighEnd)); 992 __ Subu(a0, backtrack_stackpointer(), a1); 993 __ sw(a0, register_location(reg)); 994} 995 996 997// Private methods: 998 999void RegExpMacroAssemblerMIPS::CallCheckStackGuardState(Register scratch) { 1000 static const int num_arguments = 3; 1001 __ PrepareCallCFunction(num_arguments, scratch); 1002 __ mov(a2, frame_pointer()); 1003 // Code* of self. 1004 __ li(a1, Operand(masm_->CodeObject())); 1005 // a0 becomes return address pointer. 1006 ExternalReference stack_guard_check = 1007 ExternalReference::re_check_stack_guard_state(masm_->isolate()); 1008 CallCFunctionUsingStub(stack_guard_check, num_arguments); 1009} 1010 1011 1012// Helper function for reading a value out of a stack frame. 1013template <typename T> 1014static T& frame_entry(Address re_frame, int frame_offset) { 1015 return reinterpret_cast<T&>(Memory::int32_at(re_frame + frame_offset)); 1016} 1017 1018 1019int RegExpMacroAssemblerMIPS::CheckStackGuardState(Address* return_address, 1020 Code* re_code, 1021 Address re_frame) { 1022 Isolate* isolate = frame_entry<Isolate*>(re_frame, kIsolate); 1023 ASSERT(isolate == Isolate::Current()); 1024 if (isolate->stack_guard()->IsStackOverflow()) { 1025 isolate->StackOverflow(); 1026 return EXCEPTION; 1027 } 1028 1029 // If not real stack overflow the stack guard was used to interrupt 1030 // execution for another purpose. 1031 1032 // If this is a direct call from JavaScript retry the RegExp forcing the call 1033 // through the runtime system. Currently the direct call cannot handle a GC. 1034 if (frame_entry<int>(re_frame, kDirectCall) == 1) { 1035 return RETRY; 1036 } 1037 1038 // Prepare for possible GC. 1039 HandleScope handles(isolate); 1040 Handle<Code> code_handle(re_code); 1041 1042 Handle<String> subject(frame_entry<String*>(re_frame, kInputString)); 1043 // Current string. 1044 bool is_ascii = subject->IsAsciiRepresentationUnderneath(); 1045 1046 ASSERT(re_code->instruction_start() <= *return_address); 1047 ASSERT(*return_address <= 1048 re_code->instruction_start() + re_code->instruction_size()); 1049 1050 MaybeObject* result = Execution::HandleStackGuardInterrupt(); 1051 1052 if (*code_handle != re_code) { // Return address no longer valid. 1053 int delta = code_handle->address() - re_code->address(); 1054 // Overwrite the return address on the stack. 1055 *return_address += delta; 1056 } 1057 1058 if (result->IsException()) { 1059 return EXCEPTION; 1060 } 1061 1062 Handle<String> subject_tmp = subject; 1063 int slice_offset = 0; 1064 1065 // Extract the underlying string and the slice offset. 1066 if (StringShape(*subject_tmp).IsCons()) { 1067 subject_tmp = Handle<String>(ConsString::cast(*subject_tmp)->first()); 1068 } else if (StringShape(*subject_tmp).IsSliced()) { 1069 SlicedString* slice = SlicedString::cast(*subject_tmp); 1070 subject_tmp = Handle<String>(slice->parent()); 1071 slice_offset = slice->offset(); 1072 } 1073 1074 // String might have changed. 1075 if (subject_tmp->IsAsciiRepresentation() != is_ascii) { 1076 // If we changed between an ASCII and an UC16 string, the specialized 1077 // code cannot be used, and we need to restart regexp matching from 1078 // scratch (including, potentially, compiling a new version of the code). 1079 return RETRY; 1080 } 1081 1082 // Otherwise, the content of the string might have moved. It must still 1083 // be a sequential or external string with the same content. 1084 // Update the start and end pointers in the stack frame to the current 1085 // location (whether it has actually moved or not). 1086 ASSERT(StringShape(*subject_tmp).IsSequential() || 1087 StringShape(*subject_tmp).IsExternal()); 1088 1089 // The original start address of the characters to match. 1090 const byte* start_address = frame_entry<const byte*>(re_frame, kInputStart); 1091 1092 // Find the current start address of the same character at the current string 1093 // position. 1094 int start_index = frame_entry<int>(re_frame, kStartIndex); 1095 const byte* new_address = StringCharacterPosition(*subject_tmp, 1096 start_index + slice_offset); 1097 1098 if (start_address != new_address) { 1099 // If there is a difference, update the object pointer and start and end 1100 // addresses in the RegExp stack frame to match the new value. 1101 const byte* end_address = frame_entry<const byte* >(re_frame, kInputEnd); 1102 int byte_length = static_cast<int>(end_address - start_address); 1103 frame_entry<const String*>(re_frame, kInputString) = *subject; 1104 frame_entry<const byte*>(re_frame, kInputStart) = new_address; 1105 frame_entry<const byte*>(re_frame, kInputEnd) = new_address + byte_length; 1106 } 1107 1108 return 0; 1109} 1110 1111 1112MemOperand RegExpMacroAssemblerMIPS::register_location(int register_index) { 1113 ASSERT(register_index < (1<<30)); 1114 if (num_registers_ <= register_index) { 1115 num_registers_ = register_index + 1; 1116 } 1117 return MemOperand(frame_pointer(), 1118 kRegisterZero - register_index * kPointerSize); 1119} 1120 1121 1122void RegExpMacroAssemblerMIPS::CheckPosition(int cp_offset, 1123 Label* on_outside_input) { 1124 BranchOrBacktrack(on_outside_input, 1125 ge, 1126 current_input_offset(), 1127 Operand(-cp_offset * char_size())); 1128} 1129 1130 1131void RegExpMacroAssemblerMIPS::BranchOrBacktrack(Label* to, 1132 Condition condition, 1133 Register rs, 1134 const Operand& rt) { 1135 if (condition == al) { // Unconditional. 1136 if (to == NULL) { 1137 Backtrack(); 1138 return; 1139 } 1140 __ jmp(to); 1141 return; 1142 } 1143 if (to == NULL) { 1144 __ Branch(&backtrack_label_, condition, rs, rt); 1145 return; 1146 } 1147 __ Branch(to, condition, rs, rt); 1148} 1149 1150 1151void RegExpMacroAssemblerMIPS::SafeCall(Label* to, Condition cond, Register rs, 1152 const Operand& rt) { 1153 __ BranchAndLink(to, cond, rs, rt); 1154} 1155 1156 1157void RegExpMacroAssemblerMIPS::SafeReturn() { 1158 __ pop(ra); 1159 __ Addu(t5, ra, Operand(masm_->CodeObject())); 1160 __ Jump(t5); 1161} 1162 1163 1164void RegExpMacroAssemblerMIPS::SafeCallTarget(Label* name) { 1165 __ bind(name); 1166 __ Subu(ra, ra, Operand(masm_->CodeObject())); 1167 __ push(ra); 1168} 1169 1170 1171void RegExpMacroAssemblerMIPS::Push(Register source) { 1172 ASSERT(!source.is(backtrack_stackpointer())); 1173 __ Addu(backtrack_stackpointer(), 1174 backtrack_stackpointer(), 1175 Operand(-kPointerSize)); 1176 __ sw(source, MemOperand(backtrack_stackpointer())); 1177} 1178 1179 1180void RegExpMacroAssemblerMIPS::Pop(Register target) { 1181 ASSERT(!target.is(backtrack_stackpointer())); 1182 __ lw(target, MemOperand(backtrack_stackpointer())); 1183 __ Addu(backtrack_stackpointer(), backtrack_stackpointer(), kPointerSize); 1184} 1185 1186 1187void RegExpMacroAssemblerMIPS::CheckPreemption() { 1188 // Check for preemption. 1189 ExternalReference stack_limit = 1190 ExternalReference::address_of_stack_limit(masm_->isolate()); 1191 __ li(a0, Operand(stack_limit)); 1192 __ lw(a0, MemOperand(a0)); 1193 SafeCall(&check_preempt_label_, ls, sp, Operand(a0)); 1194} 1195 1196 1197void RegExpMacroAssemblerMIPS::CheckStackLimit() { 1198 ExternalReference stack_limit = 1199 ExternalReference::address_of_regexp_stack_limit(masm_->isolate()); 1200 1201 __ li(a0, Operand(stack_limit)); 1202 __ lw(a0, MemOperand(a0)); 1203 SafeCall(&stack_overflow_label_, ls, backtrack_stackpointer(), Operand(a0)); 1204} 1205 1206 1207void RegExpMacroAssemblerMIPS::CallCFunctionUsingStub( 1208 ExternalReference function, 1209 int num_arguments) { 1210 // Must pass all arguments in registers. The stub pushes on the stack. 1211 ASSERT(num_arguments <= 4); 1212 __ li(code_pointer(), Operand(function)); 1213 RegExpCEntryStub stub; 1214 __ CallStub(&stub); 1215 if (OS::ActivationFrameAlignment() != 0) { 1216 __ lw(sp, MemOperand(sp, 16)); 1217 } 1218 __ li(code_pointer(), Operand(masm_->CodeObject())); 1219} 1220 1221 1222void RegExpMacroAssemblerMIPS::LoadCurrentCharacterUnchecked(int cp_offset, 1223 int characters) { 1224 Register offset = current_input_offset(); 1225 if (cp_offset != 0) { 1226 __ Addu(a0, current_input_offset(), Operand(cp_offset * char_size())); 1227 offset = a0; 1228 } 1229 // We assume that we cannot do unaligned loads on MIPS, so this function 1230 // must only be used to load a single character at a time. 1231 ASSERT(characters == 1); 1232 __ Addu(t5, end_of_input_address(), Operand(offset)); 1233 if (mode_ == ASCII) { 1234 __ lbu(current_character(), MemOperand(t5, 0)); 1235 } else { 1236 ASSERT(mode_ == UC16); 1237 __ lhu(current_character(), MemOperand(t5, 0)); 1238 } 1239} 1240 1241 1242void RegExpCEntryStub::Generate(MacroAssembler* masm_) { 1243 int stack_alignment = OS::ActivationFrameAlignment(); 1244 if (stack_alignment < kPointerSize) stack_alignment = kPointerSize; 1245 // Stack is already aligned for call, so decrement by alignment 1246 // to make room for storing the return address. 1247 __ Subu(sp, sp, Operand(stack_alignment)); 1248 __ sw(ra, MemOperand(sp, 0)); 1249 __ mov(a0, sp); 1250 __ mov(t9, t1); 1251 __ Call(t9); 1252 __ lw(ra, MemOperand(sp, 0)); 1253 __ Addu(sp, sp, Operand(stack_alignment)); 1254 __ Jump(ra); 1255} 1256 1257 1258#undef __ 1259 1260#endif // V8_INTERPRETED_REGEXP 1261 1262}} // namespace v8::internal 1263 1264#endif // V8_TARGET_ARCH_MIPS 1265