// Copyright 2012 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #if V8_TARGET_ARCH_IA32 #include "src/regexp/ia32/regexp-macro-assembler-ia32.h" #include "src/codegen/assembler-inl.h" #include "src/codegen/macro-assembler.h" #include "src/logging/log.h" #include "src/objects/objects-inl.h" #include "src/regexp/regexp-macro-assembler.h" #include "src/regexp/regexp-stack.h" #include "src/strings/unicode.h" namespace v8 { namespace internal { /* * This assembler uses the following register assignment convention * - edx : Current character. Must be loaded using LoadCurrentCharacter * before using any of the dispatch methods. Temporarily stores the * index of capture start after a matching pass for a global regexp. * - edi : Current position in input, as negative offset from end of string. * Please notice that this is the byte offset, not the character offset! * - esi : end of input (points to byte after last character in input). * - ebp : Frame pointer. Used to access arguments, local variables and * RegExp registers. * - esp : Points to tip of C stack. * - ecx : Points to tip of backtrack stack * * The registers eax and ebx are free to use for computations. * * Each call to a public method should retain this convention. * The stack will have the following structure: * - Address regexp (address of the JSRegExp object; unused in * native code, passed to match signature of * the interpreter) * - Isolate* isolate (address of the current isolate) * - direct_call (if 1, direct call from JavaScript code, if 0 * call through the runtime system) * - stack_area_base (high end of the memory area to use as * backtracking stack) * - capture array size (may fit multiple sets of matches) * - int* capture_array (int[num_saved_registers_], for output). * - end of input (address of end of string) * - start of input (address of first character in string) * - start index (character index of start) * - String input_string (location of a handle containing the string) * --- frame alignment (if applicable) --- * - return address * ebp-> - old ebp * - backup of caller esi * - backup of caller edi * - backup of caller ebx * - success counter (only for global regexps to count matches). * - Offset of location before start of input (effectively character * string start - 1). Used to initialize capture registers to a * non-position. * - register 0 ebp[-4] (only positions must be stored in the first * - register 1 ebp[-8] num_saved_registers_ registers) * - ... * * The first num_saved_registers_ registers are initialized to point to * "character -1" in the string (i.e., char_size() bytes before the first * character of the string). The remaining registers starts out as garbage. * * The data up to the return address must be placed there by the calling * code, by calling the code entry as cast to a function with the signature: * int (*match)(String input_string, * int start_index, * Address start, * Address end, * int* capture_output_array, * int num_capture_registers, * byte* stack_area_base, * bool direct_call = false, * Isolate* isolate * Address regexp); */ #define __ ACCESS_MASM(masm_) const int RegExpMacroAssemblerIA32::kRegExpCodeSize; RegExpMacroAssemblerIA32::RegExpMacroAssemblerIA32(Isolate* isolate, Zone* zone, Mode mode, int registers_to_save) : NativeRegExpMacroAssembler(isolate, zone), masm_(new MacroAssembler(isolate, CodeObjectRequired::kYes, NewAssemblerBuffer(kRegExpCodeSize))), mode_(mode), num_registers_(registers_to_save), num_saved_registers_(registers_to_save), entry_label_(), start_label_(), success_label_(), backtrack_label_(), exit_label_() { // Irregexp code clobbers ebx and spills/restores it at all boundaries. masm_->set_root_array_available(false); DCHECK_EQ(0, registers_to_save % 2); __ jmp(&entry_label_); // We'll write the entry code later. __ bind(&start_label_); // And then continue from here. } RegExpMacroAssemblerIA32::~RegExpMacroAssemblerIA32() { delete masm_; // Unuse labels in case we throw away the assembler without calling GetCode. entry_label_.Unuse(); start_label_.Unuse(); success_label_.Unuse(); backtrack_label_.Unuse(); exit_label_.Unuse(); check_preempt_label_.Unuse(); stack_overflow_label_.Unuse(); } int RegExpMacroAssemblerIA32::stack_limit_slack() { return RegExpStack::kStackLimitSlack; } void RegExpMacroAssemblerIA32::AdvanceCurrentPosition(int by) { if (by != 0) { __ add(edi, Immediate(by * char_size())); } } void RegExpMacroAssemblerIA32::AdvanceRegister(int reg, int by) { DCHECK_LE(0, reg); DCHECK_GT(num_registers_, reg); if (by != 0) { __ add(register_location(reg), Immediate(by)); } } void RegExpMacroAssemblerIA32::Backtrack() { CheckPreemption(); // Pop Code offset from backtrack stack, add Code and jump to location. Pop(ebx); __ add(ebx, Immediate(masm_->CodeObject())); __ jmp(ebx); } void RegExpMacroAssemblerIA32::Bind(Label* label) { __ bind(label); } void RegExpMacroAssemblerIA32::CheckCharacter(uint32_t c, Label* on_equal) { __ cmp(current_character(), c); BranchOrBacktrack(equal, on_equal); } void RegExpMacroAssemblerIA32::CheckCharacterGT(uc16 limit, Label* on_greater) { __ cmp(current_character(), limit); BranchOrBacktrack(greater, on_greater); } void RegExpMacroAssemblerIA32::CheckAtStart(int cp_offset, Label* on_at_start) { __ lea(eax, Operand(edi, -char_size() + cp_offset * char_size())); __ cmp(eax, Operand(ebp, kStringStartMinusOne)); BranchOrBacktrack(equal, on_at_start); } void RegExpMacroAssemblerIA32::CheckNotAtStart(int cp_offset, Label* on_not_at_start) { __ lea(eax, Operand(edi, -char_size() + cp_offset * char_size())); __ cmp(eax, Operand(ebp, kStringStartMinusOne)); BranchOrBacktrack(not_equal, on_not_at_start); } void RegExpMacroAssemblerIA32::CheckCharacterLT(uc16 limit, Label* on_less) { __ cmp(current_character(), limit); BranchOrBacktrack(less, on_less); } void RegExpMacroAssemblerIA32::CheckGreedyLoop(Label* on_equal) { Label fallthrough; __ cmp(edi, Operand(backtrack_stackpointer(), 0)); __ j(not_equal, &fallthrough); __ add(backtrack_stackpointer(), Immediate(kSystemPointerSize)); // Pop. BranchOrBacktrack(no_condition, on_equal); __ bind(&fallthrough); } void RegExpMacroAssemblerIA32::CheckNotBackReferenceIgnoreCase( int start_reg, bool read_backward, bool unicode, Label* on_no_match) { Label fallthrough; __ mov(edx, register_location(start_reg)); // Index of start of capture __ mov(ebx, register_location(start_reg + 1)); // Index of end of capture __ sub(ebx, edx); // Length of capture. // At this point, the capture registers are either both set or both cleared. // If the capture length is zero, then the capture is either empty or cleared. // Fall through in both cases. __ j(equal, &fallthrough); // Check that there are sufficient characters left in the input. if (read_backward) { __ mov(eax, Operand(ebp, kStringStartMinusOne)); __ add(eax, ebx); __ cmp(edi, eax); BranchOrBacktrack(less_equal, on_no_match); } else { __ mov(eax, edi); __ add(eax, ebx); BranchOrBacktrack(greater, on_no_match); } if (mode_ == LATIN1) { Label success; Label fail; Label loop_increment; // Save register contents to make the registers available below. __ push(edi); __ push(backtrack_stackpointer()); // After this, the eax, ecx, and edi registers are available. __ add(edx, esi); // Start of capture __ add(edi, esi); // Start of text to match against capture. if (read_backward) { __ sub(edi, ebx); // Offset by length when matching backwards. } __ add(ebx, edi); // End of text to match against capture. Label loop; __ bind(&loop); __ movzx_b(eax, Operand(edi, 0)); __ cmpb_al(Operand(edx, 0)); __ j(equal, &loop_increment); // Mismatch, try case-insensitive match (converting letters to lower-case). __ or_(eax, 0x20); // Convert match character to lower-case. __ lea(ecx, Operand(eax, -'a')); __ cmp(ecx, static_cast('z' - 'a')); // Is eax a lowercase letter? Label convert_capture; __ j(below_equal, &convert_capture); // In range 'a'-'z'. // Latin-1: Check for values in range [224,254] but not 247. __ sub(ecx, Immediate(224 - 'a')); __ cmp(ecx, Immediate(254 - 224)); __ j(above, &fail); // Weren't Latin-1 letters. __ cmp(ecx, Immediate(247 - 224)); // Check for 247. __ j(equal, &fail); __ bind(&convert_capture); // Also convert capture character. __ movzx_b(ecx, Operand(edx, 0)); __ or_(ecx, 0x20); __ cmp(eax, ecx); __ j(not_equal, &fail); __ bind(&loop_increment); // Increment pointers into match and capture strings. __ add(edx, Immediate(1)); __ add(edi, Immediate(1)); // Compare to end of match, and loop if not done. __ cmp(edi, ebx); __ j(below, &loop); __ jmp(&success); __ bind(&fail); // Restore original values before failing. __ pop(backtrack_stackpointer()); __ pop(edi); BranchOrBacktrack(no_condition, on_no_match); __ bind(&success); // Restore original value before continuing. __ pop(backtrack_stackpointer()); // Drop original value of character position. __ add(esp, Immediate(kSystemPointerSize)); // Compute new value of character position after the matched part. __ sub(edi, esi); if (read_backward) { // Subtract match length if we matched backward. __ add(edi, register_location(start_reg)); __ sub(edi, register_location(start_reg + 1)); } } else { DCHECK(mode_ == UC16); // Save registers before calling C function. __ push(esi); __ push(edi); __ push(backtrack_stackpointer()); __ push(ebx); static const int argument_count = 4; __ PrepareCallCFunction(argument_count, ecx); // Put arguments into allocated stack area, last argument highest on stack. // Parameters are // Address byte_offset1 - Address captured substring's start. // Address byte_offset2 - Address of current character position. // size_t byte_length - length of capture in bytes(!) // Isolate* isolate or 0 if unicode flag. // Set isolate. #ifdef V8_INTL_SUPPORT if (unicode) { __ mov(Operand(esp, 3 * kSystemPointerSize), Immediate(0)); } else // NOLINT #endif // V8_INTL_SUPPORT { __ mov(Operand(esp, 3 * kSystemPointerSize), Immediate(ExternalReference::isolate_address(isolate()))); } // Set byte_length. __ mov(Operand(esp, 2 * kSystemPointerSize), ebx); // Set byte_offset2. // Found by adding negative string-end offset of current position (edi) // to end of string. __ add(edi, esi); if (read_backward) { __ sub(edi, ebx); // Offset by length when matching backwards. } __ mov(Operand(esp, 1 * kSystemPointerSize), edi); // Set byte_offset1. // Start of capture, where edx already holds string-end negative offset. __ add(edx, esi); __ mov(Operand(esp, 0 * kSystemPointerSize), edx); { AllowExternalCallThatCantCauseGC scope(masm_); ExternalReference compare = ExternalReference::re_case_insensitive_compare_uc16(isolate()); __ CallCFunction(compare, argument_count); } // Pop original values before reacting on result value. __ pop(ebx); __ pop(backtrack_stackpointer()); __ pop(edi); __ pop(esi); // Check if function returned non-zero for success or zero for failure. __ or_(eax, eax); BranchOrBacktrack(zero, on_no_match); // On success, advance position by length of capture. if (read_backward) { __ sub(edi, ebx); } else { __ add(edi, ebx); } } __ bind(&fallthrough); } void RegExpMacroAssemblerIA32::CheckNotBackReference(int start_reg, bool read_backward, Label* on_no_match) { Label fallthrough; Label success; Label fail; // Find length of back-referenced capture. __ mov(edx, register_location(start_reg)); __ mov(eax, register_location(start_reg + 1)); __ sub(eax, edx); // Length to check. // At this point, the capture registers are either both set or both cleared. // If the capture length is zero, then the capture is either empty or cleared. // Fall through in both cases. __ j(equal, &fallthrough); // Check that there are sufficient characters left in the input. if (read_backward) { __ mov(ebx, Operand(ebp, kStringStartMinusOne)); __ add(ebx, eax); __ cmp(edi, ebx); BranchOrBacktrack(less_equal, on_no_match); } else { __ mov(ebx, edi); __ add(ebx, eax); BranchOrBacktrack(greater, on_no_match); } // Save register to make it available below. __ push(backtrack_stackpointer()); // Compute pointers to match string and capture string __ add(edx, esi); // Start of capture. __ lea(ebx, Operand(esi, edi, times_1, 0)); // Start of match. if (read_backward) { __ sub(ebx, eax); // Offset by length when matching backwards. } __ lea(ecx, Operand(eax, ebx, times_1, 0)); // End of match Label loop; __ bind(&loop); if (mode_ == LATIN1) { __ movzx_b(eax, Operand(edx, 0)); __ cmpb_al(Operand(ebx, 0)); } else { DCHECK(mode_ == UC16); __ movzx_w(eax, Operand(edx, 0)); __ cmpw_ax(Operand(ebx, 0)); } __ j(not_equal, &fail); // Increment pointers into capture and match string. __ add(edx, Immediate(char_size())); __ add(ebx, Immediate(char_size())); // Check if we have reached end of match area. __ cmp(ebx, ecx); __ j(below, &loop); __ jmp(&success); __ bind(&fail); // Restore backtrack stackpointer. __ pop(backtrack_stackpointer()); BranchOrBacktrack(no_condition, on_no_match); __ bind(&success); // Move current character position to position after match. __ mov(edi, ecx); __ sub(edi, esi); if (read_backward) { // Subtract match length if we matched backward. __ add(edi, register_location(start_reg)); __ sub(edi, register_location(start_reg + 1)); } // Restore backtrack stackpointer. __ pop(backtrack_stackpointer()); __ bind(&fallthrough); } void RegExpMacroAssemblerIA32::CheckNotCharacter(uint32_t c, Label* on_not_equal) { __ cmp(current_character(), c); BranchOrBacktrack(not_equal, on_not_equal); } void RegExpMacroAssemblerIA32::CheckCharacterAfterAnd(uint32_t c, uint32_t mask, Label* on_equal) { if (c == 0) { __ test(current_character(), Immediate(mask)); } else { __ mov(eax, mask); __ and_(eax, current_character()); __ cmp(eax, c); } BranchOrBacktrack(equal, on_equal); } void RegExpMacroAssemblerIA32::CheckNotCharacterAfterAnd(uint32_t c, uint32_t mask, Label* on_not_equal) { if (c == 0) { __ test(current_character(), Immediate(mask)); } else { __ mov(eax, mask); __ and_(eax, current_character()); __ cmp(eax, c); } BranchOrBacktrack(not_equal, on_not_equal); } void RegExpMacroAssemblerIA32::CheckNotCharacterAfterMinusAnd( uc16 c, uc16 minus, uc16 mask, Label* on_not_equal) { DCHECK_GT(String::kMaxUtf16CodeUnit, minus); __ lea(eax, Operand(current_character(), -minus)); if (c == 0) { __ test(eax, Immediate(mask)); } else { __ and_(eax, mask); __ cmp(eax, c); } BranchOrBacktrack(not_equal, on_not_equal); } void RegExpMacroAssemblerIA32::CheckCharacterInRange( uc16 from, uc16 to, Label* on_in_range) { __ lea(eax, Operand(current_character(), -from)); __ cmp(eax, to - from); BranchOrBacktrack(below_equal, on_in_range); } void RegExpMacroAssemblerIA32::CheckCharacterNotInRange( uc16 from, uc16 to, Label* on_not_in_range) { __ lea(eax, Operand(current_character(), -from)); __ cmp(eax, to - from); BranchOrBacktrack(above, on_not_in_range); } void RegExpMacroAssemblerIA32::CheckBitInTable( Handle table, Label* on_bit_set) { __ mov(eax, Immediate(table)); Register index = current_character(); if (mode_ != LATIN1 || kTableMask != String::kMaxOneByteCharCode) { __ mov(ebx, kTableSize - 1); __ and_(ebx, current_character()); index = ebx; } __ cmpb(FieldOperand(eax, index, times_1, ByteArray::kHeaderSize), Immediate(0)); BranchOrBacktrack(not_equal, on_bit_set); } bool RegExpMacroAssemblerIA32::CheckSpecialCharacterClass(uc16 type, Label* on_no_match) { // Range checks (c in min..max) are generally implemented by an unsigned // (c - min) <= (max - min) check switch (type) { case 's': // Match space-characters if (mode_ == LATIN1) { // One byte space characters are '\t'..'\r', ' ' and \u00a0. Label success; __ cmp(current_character(), ' '); __ j(equal, &success, Label::kNear); // Check range 0x09..0x0D __ lea(eax, Operand(current_character(), -'\t')); __ cmp(eax, '\r' - '\t'); __ j(below_equal, &success, Label::kNear); // \u00a0 (NBSP). __ cmp(eax, 0x00A0 - '\t'); BranchOrBacktrack(not_equal, on_no_match); __ bind(&success); return true; } return false; case 'S': // The emitted code for generic character classes is good enough. return false; case 'd': // Match ASCII digits ('0'..'9') __ lea(eax, Operand(current_character(), -'0')); __ cmp(eax, '9' - '0'); BranchOrBacktrack(above, on_no_match); return true; case 'D': // Match non ASCII-digits __ lea(eax, Operand(current_character(), -'0')); __ cmp(eax, '9' - '0'); BranchOrBacktrack(below_equal, on_no_match); return true; case '.': { // Match non-newlines (not 0x0A('\n'), 0x0D('\r'), 0x2028 and 0x2029) __ mov(eax, current_character()); __ xor_(eax, Immediate(0x01)); // See if current character is '\n'^1 or '\r'^1, i.e., 0x0B or 0x0C __ sub(eax, Immediate(0x0B)); __ cmp(eax, 0x0C - 0x0B); BranchOrBacktrack(below_equal, on_no_match); if (mode_ == UC16) { // Compare original value to 0x2028 and 0x2029, using the already // computed (current_char ^ 0x01 - 0x0B). I.e., check for // 0x201D (0x2028 - 0x0B) or 0x201E. __ sub(eax, Immediate(0x2028 - 0x0B)); __ cmp(eax, 0x2029 - 0x2028); BranchOrBacktrack(below_equal, on_no_match); } return true; } case 'w': { if (mode_ != LATIN1) { // Table is 256 entries, so all Latin1 characters can be tested. __ cmp(current_character(), Immediate('z')); BranchOrBacktrack(above, on_no_match); } DCHECK_EQ(0, word_character_map[0]); // Character '\0' is not a word char. ExternalReference word_map = ExternalReference::re_word_character_map(isolate()); __ test_b(current_character(), Operand(current_character(), times_1, word_map.address(), RelocInfo::EXTERNAL_REFERENCE)); BranchOrBacktrack(zero, on_no_match); return true; } case 'W': { Label done; if (mode_ != LATIN1) { // Table is 256 entries, so all Latin1 characters can be tested. __ cmp(current_character(), Immediate('z')); __ j(above, &done); } DCHECK_EQ(0, word_character_map[0]); // Character '\0' is not a word char. ExternalReference word_map = ExternalReference::re_word_character_map(isolate()); __ test_b(current_character(), Operand(current_character(), times_1, word_map.address(), RelocInfo::EXTERNAL_REFERENCE)); BranchOrBacktrack(not_zero, on_no_match); if (mode_ != LATIN1) { __ bind(&done); } return true; } // Non-standard classes (with no syntactic shorthand) used internally. case '*': // Match any character. return true; case 'n': { // Match newlines (0x0A('\n'), 0x0D('\r'), 0x2028 or 0x2029). // The opposite of '.'. __ mov(eax, current_character()); __ xor_(eax, Immediate(0x01)); // See if current character is '\n'^1 or '\r'^1, i.e., 0x0B or 0x0C __ sub(eax, Immediate(0x0B)); __ cmp(eax, 0x0C - 0x0B); if (mode_ == LATIN1) { BranchOrBacktrack(above, on_no_match); } else { Label done; BranchOrBacktrack(below_equal, &done); DCHECK_EQ(UC16, mode_); // Compare original value to 0x2028 and 0x2029, using the already // computed (current_char ^ 0x01 - 0x0B). I.e., check for // 0x201D (0x2028 - 0x0B) or 0x201E. __ sub(eax, Immediate(0x2028 - 0x0B)); __ cmp(eax, 1); BranchOrBacktrack(above, on_no_match); __ bind(&done); } return true; } // No custom implementation (yet): s(UC16), S(UC16). default: return false; } } void RegExpMacroAssemblerIA32::Fail() { STATIC_ASSERT(FAILURE == 0); // Return value for failure is zero. if (!global()) { __ Move(eax, Immediate(FAILURE)); } __ jmp(&exit_label_); } Handle RegExpMacroAssemblerIA32::GetCode(Handle source) { Label return_eax; // Finalize code - write the entry point code now we know how many // registers we need. // Entry code: __ bind(&entry_label_); // Tell the system that we have a stack frame. Because the type is MANUAL, no // code is generated. FrameScope scope(masm_, StackFrame::MANUAL); // Actually emit code to start a new stack frame. __ push(ebp); __ mov(ebp, esp); // Save callee-save registers. Order here should correspond to order of // kBackup_ebx etc. __ push(esi); __ push(edi); __ push(ebx); // Callee-save on MacOS. __ push(Immediate(0)); // Number of successful matches in a global regexp. __ push(Immediate(0)); // Make room for "string start - 1" constant. // Check if we have space on the stack for registers. Label stack_limit_hit; Label stack_ok; ExternalReference stack_limit = ExternalReference::address_of_jslimit(isolate()); __ mov(ecx, esp); __ sub(ecx, StaticVariable(stack_limit)); // Handle it if the stack pointer is already below the stack limit. __ j(below_equal, &stack_limit_hit); // Check if there is room for the variable number of registers above // the stack limit. __ cmp(ecx, num_registers_ * kSystemPointerSize); __ j(above_equal, &stack_ok); // Exit with OutOfMemory exception. There is not enough space on the stack // for our working registers. __ mov(eax, EXCEPTION); __ jmp(&return_eax); __ bind(&stack_limit_hit); CallCheckStackGuardState(ebx); __ or_(eax, eax); // If returned value is non-zero, we exit with the returned value as result. __ j(not_zero, &return_eax); __ bind(&stack_ok); // Load start index for later use. __ mov(ebx, Operand(ebp, kStartIndex)); // Allocate space on stack for registers. __ AllocateStackSpace(num_registers_ * kSystemPointerSize); // Load string length. __ mov(esi, Operand(ebp, kInputEnd)); // Load input position. __ mov(edi, Operand(ebp, kInputStart)); // Set up edi to be negative offset from string end. __ sub(edi, esi); // Set eax to address of char before start of the string. // (effectively string position -1). __ neg(ebx); if (mode_ == UC16) { __ lea(eax, Operand(edi, ebx, times_2, -char_size())); } else { __ lea(eax, Operand(edi, ebx, times_1, -char_size())); } // Store this value in a local variable, for use when clearing // position registers. __ mov(Operand(ebp, kStringStartMinusOne), eax); Label load_char_start_regexp, start_regexp; // Load newline if index is at start, previous character otherwise. __ cmp(Operand(ebp, kStartIndex), Immediate(0)); __ j(not_equal, &load_char_start_regexp, Label::kNear); __ mov(current_character(), '\n'); __ jmp(&start_regexp, Label::kNear); // Global regexp restarts matching here. __ bind(&load_char_start_regexp); // Load previous char as initial value of current character register. LoadCurrentCharacterUnchecked(-1, 1); __ bind(&start_regexp); // Initialize on-stack registers. if (num_saved_registers_ > 0) { // Always is, if generated from a regexp. // Fill saved registers with initial value = start offset - 1 // Fill in stack push order, to avoid accessing across an unwritten // page (a problem on Windows). if (num_saved_registers_ > 8) { __ mov(ecx, kRegisterZero); Label init_loop; __ bind(&init_loop); __ mov(Operand(ebp, ecx, times_1, 0), eax); __ sub(ecx, Immediate(kSystemPointerSize)); __ cmp(ecx, kRegisterZero - num_saved_registers_ * kSystemPointerSize); __ j(greater, &init_loop); } else { // Unroll the loop. for (int i = 0; i < num_saved_registers_; i++) { __ mov(register_location(i), eax); } } } // Initialize backtrack stack pointer. __ mov(backtrack_stackpointer(), Operand(ebp, kStackHighEnd)); __ jmp(&start_label_); // Exit code: if (success_label_.is_linked()) { // Save captures when successful. __ bind(&success_label_); if (num_saved_registers_ > 0) { // copy captures to output __ mov(ebx, Operand(ebp, kRegisterOutput)); __ mov(ecx, Operand(ebp, kInputEnd)); __ mov(edx, Operand(ebp, kStartIndex)); __ sub(ecx, Operand(ebp, kInputStart)); if (mode_ == UC16) { __ lea(ecx, Operand(ecx, edx, times_2, 0)); } else { __ add(ecx, edx); } for (int i = 0; i < num_saved_registers_; i++) { __ mov(eax, register_location(i)); if (i == 0 && global_with_zero_length_check()) { // Keep capture start in edx for the zero-length check later. __ mov(edx, eax); } // Convert to index from start of string, not end. __ add(eax, ecx); if (mode_ == UC16) { __ sar(eax, 1); // Convert byte index to character index. } __ mov(Operand(ebx, i * kSystemPointerSize), eax); } } if (global()) { // Restart matching if the regular expression is flagged as global. // Increment success counter. __ inc(Operand(ebp, kSuccessfulCaptures)); // Capture results have been stored, so the number of remaining global // output registers is reduced by the number of stored captures. __ mov(ecx, Operand(ebp, kNumOutputRegisters)); __ sub(ecx, Immediate(num_saved_registers_)); // Check whether we have enough room for another set of capture results. __ cmp(ecx, Immediate(num_saved_registers_)); __ j(less, &exit_label_); __ mov(Operand(ebp, kNumOutputRegisters), ecx); // Advance the location for output. __ add(Operand(ebp, kRegisterOutput), Immediate(num_saved_registers_ * kSystemPointerSize)); // Prepare eax to initialize registers with its value in the next run. __ mov(eax, Operand(ebp, kStringStartMinusOne)); if (global_with_zero_length_check()) { // Special case for zero-length matches. // edx: capture start index __ cmp(edi, edx); // Not a zero-length match, restart. __ j(not_equal, &load_char_start_regexp); // edi (offset from the end) is zero if we already reached the end. __ test(edi, edi); __ j(zero, &exit_label_, Label::kNear); // Advance current position after a zero-length match. Label advance; __ bind(&advance); if (mode_ == UC16) { __ add(edi, Immediate(2)); } else { __ inc(edi); } if (global_unicode()) CheckNotInSurrogatePair(0, &advance); } __ jmp(&load_char_start_regexp); } else { __ mov(eax, Immediate(SUCCESS)); } } __ bind(&exit_label_); if (global()) { // Return the number of successful captures. __ mov(eax, Operand(ebp, kSuccessfulCaptures)); } __ bind(&return_eax); // Skip esp past regexp registers. __ lea(esp, Operand(ebp, kBackup_ebx)); // Restore callee-save registers. __ pop(ebx); __ pop(edi); __ pop(esi); // Exit function frame, restore previous one. __ pop(ebp); __ ret(0); // Backtrack code (branch target for conditional backtracks). if (backtrack_label_.is_linked()) { __ bind(&backtrack_label_); Backtrack(); } Label exit_with_exception; // Preempt-code if (check_preempt_label_.is_linked()) { SafeCallTarget(&check_preempt_label_); __ push(backtrack_stackpointer()); __ push(edi); CallCheckStackGuardState(ebx); __ or_(eax, eax); // If returning non-zero, we should end execution with the given // result as return value. __ j(not_zero, &return_eax); __ pop(edi); __ pop(backtrack_stackpointer()); // String might have moved: Reload esi from frame. __ mov(esi, Operand(ebp, kInputEnd)); SafeReturn(); } // Backtrack stack overflow code. if (stack_overflow_label_.is_linked()) { SafeCallTarget(&stack_overflow_label_); // Reached if the backtrack-stack limit has been hit. // Save registers before calling C function __ push(esi); __ push(edi); // Call GrowStack(backtrack_stackpointer()) static const int num_arguments = 3; __ PrepareCallCFunction(num_arguments, ebx); __ mov(Operand(esp, 2 * kSystemPointerSize), Immediate(ExternalReference::isolate_address(isolate()))); __ lea(eax, Operand(ebp, kStackHighEnd)); __ mov(Operand(esp, 1 * kSystemPointerSize), eax); __ mov(Operand(esp, 0 * kSystemPointerSize), backtrack_stackpointer()); ExternalReference grow_stack = ExternalReference::re_grow_stack(isolate()); __ CallCFunction(grow_stack, num_arguments); // If return nullptr, we have failed to grow the stack, and // must exit with a stack-overflow exception. __ or_(eax, eax); __ j(equal, &exit_with_exception); // Otherwise use return value as new stack pointer. __ mov(backtrack_stackpointer(), eax); // Restore saved registers and continue. __ pop(edi); __ pop(esi); SafeReturn(); } if (exit_with_exception.is_linked()) { // If any of the code above needed to exit with an exception. __ bind(&exit_with_exception); // Exit with Result EXCEPTION(-1) to signal thrown exception. __ mov(eax, EXCEPTION); __ jmp(&return_eax); } CodeDesc code_desc; masm_->GetCode(masm_->isolate(), &code_desc); Handle code = Factory::CodeBuilder(isolate(), code_desc, Code::REGEXP) .set_self_reference(masm_->CodeObject()) .Build(); PROFILE(masm_->isolate(), RegExpCodeCreateEvent(AbstractCode::cast(*code), *source)); return Handle::cast(code); } void RegExpMacroAssemblerIA32::GoTo(Label* to) { BranchOrBacktrack(no_condition, to); } void RegExpMacroAssemblerIA32::IfRegisterGE(int reg, int comparand, Label* if_ge) { __ cmp(register_location(reg), Immediate(comparand)); BranchOrBacktrack(greater_equal, if_ge); } void RegExpMacroAssemblerIA32::IfRegisterLT(int reg, int comparand, Label* if_lt) { __ cmp(register_location(reg), Immediate(comparand)); BranchOrBacktrack(less, if_lt); } void RegExpMacroAssemblerIA32::IfRegisterEqPos(int reg, Label* if_eq) { __ cmp(edi, register_location(reg)); BranchOrBacktrack(equal, if_eq); } RegExpMacroAssembler::IrregexpImplementation RegExpMacroAssemblerIA32::Implementation() { return kIA32Implementation; } void RegExpMacroAssemblerIA32::LoadCurrentCharacterImpl(int cp_offset, Label* on_end_of_input, bool check_bounds, int characters, int eats_at_least) { // It's possible to preload a small number of characters when each success // path requires a large number of characters, but not the reverse. DCHECK_GE(eats_at_least, characters); DCHECK(cp_offset < (1<<30)); // Be sane! (And ensure negation works) if (check_bounds) { if (cp_offset >= 0) { CheckPosition(cp_offset + eats_at_least - 1, on_end_of_input); } else { CheckPosition(cp_offset, on_end_of_input); } } LoadCurrentCharacterUnchecked(cp_offset, characters); } void RegExpMacroAssemblerIA32::PopCurrentPosition() { Pop(edi); } void RegExpMacroAssemblerIA32::PopRegister(int register_index) { Pop(eax); __ mov(register_location(register_index), eax); } void RegExpMacroAssemblerIA32::PushBacktrack(Label* label) { Push(Immediate::CodeRelativeOffset(label)); CheckStackLimit(); } void RegExpMacroAssemblerIA32::PushCurrentPosition() { Push(edi); } void RegExpMacroAssemblerIA32::PushRegister(int register_index, StackCheckFlag check_stack_limit) { __ mov(eax, register_location(register_index)); Push(eax); if (check_stack_limit) CheckStackLimit(); } void RegExpMacroAssemblerIA32::ReadCurrentPositionFromRegister(int reg) { __ mov(edi, register_location(reg)); } void RegExpMacroAssemblerIA32::ReadStackPointerFromRegister(int reg) { __ mov(backtrack_stackpointer(), register_location(reg)); __ add(backtrack_stackpointer(), Operand(ebp, kStackHighEnd)); } void RegExpMacroAssemblerIA32::SetCurrentPositionFromEnd(int by) { Label after_position; __ cmp(edi, -by * char_size()); __ j(greater_equal, &after_position, Label::kNear); __ mov(edi, -by * char_size()); // On RegExp code entry (where this operation is used), the character before // the current position is expected to be already loaded. // We have advanced the position, so it's safe to read backwards. LoadCurrentCharacterUnchecked(-1, 1); __ bind(&after_position); } void RegExpMacroAssemblerIA32::SetRegister(int register_index, int to) { DCHECK(register_index >= num_saved_registers_); // Reserved for positions! __ mov(register_location(register_index), Immediate(to)); } bool RegExpMacroAssemblerIA32::Succeed() { __ jmp(&success_label_); return global(); } void RegExpMacroAssemblerIA32::WriteCurrentPositionToRegister(int reg, int cp_offset) { if (cp_offset == 0) { __ mov(register_location(reg), edi); } else { __ lea(eax, Operand(edi, cp_offset * char_size())); __ mov(register_location(reg), eax); } } void RegExpMacroAssemblerIA32::ClearRegisters(int reg_from, int reg_to) { DCHECK(reg_from <= reg_to); __ mov(eax, Operand(ebp, kStringStartMinusOne)); for (int reg = reg_from; reg <= reg_to; reg++) { __ mov(register_location(reg), eax); } } void RegExpMacroAssemblerIA32::WriteStackPointerToRegister(int reg) { __ mov(eax, backtrack_stackpointer()); __ sub(eax, Operand(ebp, kStackHighEnd)); __ mov(register_location(reg), eax); } // Private methods: void RegExpMacroAssemblerIA32::CallCheckStackGuardState(Register scratch) { static const int num_arguments = 3; __ PrepareCallCFunction(num_arguments, scratch); // RegExp code frame pointer. __ mov(Operand(esp, 2 * kSystemPointerSize), ebp); // Code of self. __ mov(Operand(esp, 1 * kSystemPointerSize), Immediate(masm_->CodeObject())); // Next address on the stack (will be address of return address). __ lea(eax, Operand(esp, -kSystemPointerSize)); __ mov(Operand(esp, 0 * kSystemPointerSize), eax); ExternalReference check_stack_guard = ExternalReference::re_check_stack_guard_state(isolate()); __ CallCFunction(check_stack_guard, num_arguments); } Operand RegExpMacroAssemblerIA32::StaticVariable(const ExternalReference& ext) { return Operand(ext.address(), RelocInfo::EXTERNAL_REFERENCE); } // Helper function for reading a value out of a stack frame. template static T& frame_entry(Address re_frame, int frame_offset) { return reinterpret_cast(Memory(re_frame + frame_offset)); } template static T* frame_entry_address(Address re_frame, int frame_offset) { return reinterpret_cast(re_frame + frame_offset); } int RegExpMacroAssemblerIA32::CheckStackGuardState(Address* return_address, Address raw_code, Address re_frame) { Code re_code = Code::cast(Object(raw_code)); return NativeRegExpMacroAssembler::CheckStackGuardState( frame_entry(re_frame, kIsolate), frame_entry(re_frame, kStartIndex), static_cast(frame_entry(re_frame, kDirectCall)), return_address, re_code, frame_entry_address
(re_frame, kInputString), frame_entry_address(re_frame, kInputStart), frame_entry_address(re_frame, kInputEnd)); } Operand RegExpMacroAssemblerIA32::register_location(int register_index) { DCHECK(register_index < (1<<30)); if (num_registers_ <= register_index) { num_registers_ = register_index + 1; } return Operand(ebp, kRegisterZero - register_index * kSystemPointerSize); } void RegExpMacroAssemblerIA32::CheckPosition(int cp_offset, Label* on_outside_input) { if (cp_offset >= 0) { __ cmp(edi, -cp_offset * char_size()); BranchOrBacktrack(greater_equal, on_outside_input); } else { __ lea(eax, Operand(edi, cp_offset * char_size())); __ cmp(eax, Operand(ebp, kStringStartMinusOne)); BranchOrBacktrack(less_equal, on_outside_input); } } void RegExpMacroAssemblerIA32::BranchOrBacktrack(Condition condition, Label* to) { if (condition < 0) { // No condition if (to == nullptr) { Backtrack(); return; } __ jmp(to); return; } if (to == nullptr) { __ j(condition, &backtrack_label_); return; } __ j(condition, to); } void RegExpMacroAssemblerIA32::SafeCall(Label* to) { Label return_to; __ push(Immediate::CodeRelativeOffset(&return_to)); __ jmp(to); __ bind(&return_to); } void RegExpMacroAssemblerIA32::SafeReturn() { __ pop(ebx); __ add(ebx, Immediate(masm_->CodeObject())); __ jmp(ebx); } void RegExpMacroAssemblerIA32::SafeCallTarget(Label* name) { __ bind(name); } void RegExpMacroAssemblerIA32::Push(Register source) { DCHECK(source != backtrack_stackpointer()); // Notice: This updates flags, unlike normal Push. __ sub(backtrack_stackpointer(), Immediate(kSystemPointerSize)); __ mov(Operand(backtrack_stackpointer(), 0), source); } void RegExpMacroAssemblerIA32::Push(Immediate value) { // Notice: This updates flags, unlike normal Push. __ sub(backtrack_stackpointer(), Immediate(kSystemPointerSize)); __ mov(Operand(backtrack_stackpointer(), 0), value); } void RegExpMacroAssemblerIA32::Pop(Register target) { DCHECK(target != backtrack_stackpointer()); __ mov(target, Operand(backtrack_stackpointer(), 0)); // Notice: This updates flags, unlike normal Pop. __ add(backtrack_stackpointer(), Immediate(kSystemPointerSize)); } void RegExpMacroAssemblerIA32::CheckPreemption() { // Check for preemption. Label no_preempt; ExternalReference stack_limit = ExternalReference::address_of_jslimit(isolate()); __ cmp(esp, StaticVariable(stack_limit)); __ j(above, &no_preempt); SafeCall(&check_preempt_label_); __ bind(&no_preempt); } void RegExpMacroAssemblerIA32::CheckStackLimit() { Label no_stack_overflow; ExternalReference stack_limit = ExternalReference::address_of_regexp_stack_limit_address(isolate()); __ cmp(backtrack_stackpointer(), StaticVariable(stack_limit)); __ j(above, &no_stack_overflow); SafeCall(&stack_overflow_label_); __ bind(&no_stack_overflow); } void RegExpMacroAssemblerIA32::LoadCurrentCharacterUnchecked(int cp_offset, int characters) { if (mode_ == LATIN1) { if (characters == 4) { __ mov(current_character(), Operand(esi, edi, times_1, cp_offset)); } else if (characters == 2) { __ movzx_w(current_character(), Operand(esi, edi, times_1, cp_offset)); } else { DCHECK_EQ(1, characters); __ movzx_b(current_character(), Operand(esi, edi, times_1, cp_offset)); } } else { DCHECK(mode_ == UC16); if (characters == 2) { __ mov(current_character(), Operand(esi, edi, times_1, cp_offset * sizeof(uc16))); } else { DCHECK_EQ(1, characters); __ movzx_w(current_character(), Operand(esi, edi, times_1, cp_offset * sizeof(uc16))); } } } #undef __ } // namespace internal } // namespace v8 #endif // V8_TARGET_ARCH_IA32