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Diffstat (limited to 'deps/v8/src/mips64/regexp-macro-assembler-mips64.cc')
| -rw-r--r-- | deps/v8/src/mips64/regexp-macro-assembler-mips64.cc | 1371 |
1 files changed, 1371 insertions, 0 deletions
diff --git a/deps/v8/src/mips64/regexp-macro-assembler-mips64.cc b/deps/v8/src/mips64/regexp-macro-assembler-mips64.cc new file mode 100644 index 000000000..bcd133424 --- /dev/null +++ b/deps/v8/src/mips64/regexp-macro-assembler-mips64.cc @@ -0,0 +1,1371 @@ +// 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. + +#include "src/v8.h" + +#if V8_TARGET_ARCH_MIPS64 + +#include "src/code-stubs.h" +#include "src/log.h" +#include "src/macro-assembler.h" +#include "src/regexp-macro-assembler.h" +#include "src/regexp-stack.h" +#include "src/unicode.h" + +#include "src/mips64/regexp-macro-assembler-mips64.h" + +namespace v8 { +namespace internal { + +#ifndef V8_INTERPRETED_REGEXP +/* + * This assembler uses the following register assignment convention + * - t3 : Temporarily stores the index of capture start after a matching pass + * for a global regexp. + * - a5 : Pointer to current code object (Code*) including heap object tag. + * - a6 : Current position in input, as negative offset from end of string. + * Please notice that this is the byte offset, not the character offset! + * - a7 : Currently loaded character. Must be loaded using + * LoadCurrentCharacter before using any of the dispatch methods. + * - t0 : Points to tip of backtrack stack + * - t1 : Unused. + * - t2 : End of input (points to byte after last character in input). + * - fp : Frame pointer. Used to access arguments, local variables and + * RegExp registers. + * - sp : Points to tip of C stack. + * + * The remaining registers are free for computations. + * Each call to a public method should retain this convention. + * + * TODO(plind): O32 documented here with intent of having single 32/64 codebase + * in the future. + * + * The O32 stack will have the following structure: + * + * - fp[76] Isolate* isolate (address of the current isolate) + * - fp[72] direct_call (if 1, direct call from JavaScript code, + * if 0, call through the runtime system). + * - fp[68] stack_area_base (High end of the memory area to use as + * backtracking stack). + * - fp[64] capture array size (may fit multiple sets of matches) + * - fp[60] int* capture_array (int[num_saved_registers_], for output). + * - fp[44..59] MIPS O32 four argument slots + * - fp[40] secondary link/return address used by native call. + * --- sp when called --- + * - fp[36] return address (lr). + * - fp[32] old frame pointer (r11). + * - fp[0..31] backup of registers s0..s7. + * --- frame pointer ---- + * - fp[-4] end of input (address of end of string). + * - fp[-8] start of input (address of first character in string). + * - fp[-12] start index (character index of start). + * - fp[-16] void* input_string (location of a handle containing the string). + * - fp[-20] success counter (only for global regexps to count matches). + * - fp[-24] Offset of location before start of input (effectively character + * position -1). Used to initialize capture registers to a + * non-position. + * - fp[-28] At start (if 1, we are starting at the start of the + * string, otherwise 0) + * - fp[-32] register 0 (Only positions must be stored in the first + * - register 1 num_saved_registers_ registers) + * - ... + * - register num_registers-1 + * --- sp --- + * + * + * The N64 stack will have the following structure: + * + * - fp[88] Isolate* isolate (address of the current isolate) kIsolate + * - fp[80] secondary link/return address used by exit frame on native call. kSecondaryReturnAddress + kStackFrameHeader + * --- sp when called --- + * - fp[72] ra Return from RegExp code (ra). kReturnAddress + * - fp[64] s9, old-fp Old fp, callee saved(s9). + * - fp[0..63] s0..s7 Callee-saved registers s0..s7. + * --- frame pointer ---- + * - fp[-8] direct_call (1 = direct call from JS, 0 = from runtime) kDirectCall + * - fp[-16] stack_base (Top of backtracking stack). kStackHighEnd + * - fp[-24] capture array size (may fit multiple sets of matches) kNumOutputRegisters + * - fp[-32] int* capture_array (int[num_saved_registers_], for output). kRegisterOutput + * - fp[-40] end of input (address of end of string). kInputEnd + * - fp[-48] start of input (address of first character in string). kInputStart + * - fp[-56] start index (character index of start). kStartIndex + * - fp[-64] void* input_string (location of a handle containing the string). kInputString + * - fp[-72] success counter (only for global regexps to count matches). kSuccessfulCaptures + * - fp[-80] Offset of location before start of input (effectively character kInputStartMinusOne + * position -1). Used to initialize capture registers to a + * non-position. + * --------- The following output registers are 32-bit values. --------- + * - fp[-88] register 0 (Only positions must be stored in the first kRegisterZero + * - register 1 num_saved_registers_ registers) + * - ... + * - register num_registers-1 + * --- sp --- + * + * 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 start out as garbage. + * + * The data up to the return address must be placed there by the calling + * code and the remaining arguments are passed in registers, e.g. 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, + * Address secondary_return_address, // Only used by native call. + * int* capture_output_array, + * byte* stack_area_base, + * bool direct_call = false, + * void* return_address, + * Isolate* isolate); + * The call is performed by NativeRegExpMacroAssembler::Execute() + * (in regexp-macro-assembler.cc) via the CALL_GENERATED_REGEXP_CODE macro + * in mips/simulator-mips.h. + * When calling as a non-direct call (i.e., from C++ code), the return address + * area is overwritten with the ra register by the RegExp code. When doing a + * direct call from generated code, the return address is placed there by + * the calling code, as in a normal exit frame. + */ + +#define __ ACCESS_MASM(masm_) + +RegExpMacroAssemblerMIPS::RegExpMacroAssemblerMIPS( + Mode mode, + int registers_to_save, + Zone* zone) + : NativeRegExpMacroAssembler(zone), + masm_(new MacroAssembler(zone->isolate(), NULL, kRegExpCodeSize)), + mode_(mode), + num_registers_(registers_to_save), + num_saved_registers_(registers_to_save), + entry_label_(), + start_label_(), + success_label_(), + backtrack_label_(), + exit_label_(), + internal_failure_label_() { + DCHECK_EQ(0, registers_to_save % 2); + __ jmp(&entry_label_); // We'll write the entry code later. + // If the code gets too big or corrupted, an internal exception will be + // raised, and we will exit right away. + __ bind(&internal_failure_label_); + __ li(v0, Operand(FAILURE)); + __ Ret(); + __ bind(&start_label_); // And then continue from here. +} + + +RegExpMacroAssemblerMIPS::~RegExpMacroAssemblerMIPS() { + 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(); + internal_failure_label_.Unuse(); +} + + +int RegExpMacroAssemblerMIPS::stack_limit_slack() { + return RegExpStack::kStackLimitSlack; +} + + +void RegExpMacroAssemblerMIPS::AdvanceCurrentPosition(int by) { + if (by != 0) { + __ Daddu(current_input_offset(), + current_input_offset(), Operand(by * char_size())); + } +} + + +void RegExpMacroAssemblerMIPS::AdvanceRegister(int reg, int by) { + DCHECK(reg >= 0); + DCHECK(reg < num_registers_); + if (by != 0) { + __ ld(a0, register_location(reg)); + __ Daddu(a0, a0, Operand(by)); + __ sd(a0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerMIPS::Backtrack() { + CheckPreemption(); + // Pop Code* offset from backtrack stack, add Code* and jump to location. + Pop(a0); + __ Daddu(a0, a0, code_pointer()); + __ Jump(a0); +} + + +void RegExpMacroAssemblerMIPS::Bind(Label* label) { + __ bind(label); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacter(uint32_t c, Label* on_equal) { + BranchOrBacktrack(on_equal, eq, current_character(), Operand(c)); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacterGT(uc16 limit, Label* on_greater) { + BranchOrBacktrack(on_greater, gt, current_character(), Operand(limit)); +} + + +void RegExpMacroAssemblerMIPS::CheckAtStart(Label* on_at_start) { + Label not_at_start; + // Did we start the match at the start of the string at all? + __ lw(a0, MemOperand(frame_pointer(), kStartIndex)); + BranchOrBacktrack(¬_at_start, ne, a0, Operand(zero_reg)); + + // If we did, are we still at the start of the input? + __ ld(a1, MemOperand(frame_pointer(), kInputStart)); + __ Daddu(a0, end_of_input_address(), Operand(current_input_offset())); + BranchOrBacktrack(on_at_start, eq, a0, Operand(a1)); + __ bind(¬_at_start); +} + + +void RegExpMacroAssemblerMIPS::CheckNotAtStart(Label* on_not_at_start) { + // Did we start the match at the start of the string at all? + __ lw(a0, MemOperand(frame_pointer(), kStartIndex)); + BranchOrBacktrack(on_not_at_start, ne, a0, Operand(zero_reg)); + // If we did, are we still at the start of the input? + __ ld(a1, MemOperand(frame_pointer(), kInputStart)); + __ Daddu(a0, end_of_input_address(), Operand(current_input_offset())); + BranchOrBacktrack(on_not_at_start, ne, a0, Operand(a1)); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacterLT(uc16 limit, Label* on_less) { + BranchOrBacktrack(on_less, lt, current_character(), Operand(limit)); +} + + +void RegExpMacroAssemblerMIPS::CheckGreedyLoop(Label* on_equal) { + Label backtrack_non_equal; + __ lw(a0, MemOperand(backtrack_stackpointer(), 0)); + __ Branch(&backtrack_non_equal, ne, current_input_offset(), Operand(a0)); + __ Daddu(backtrack_stackpointer(), + backtrack_stackpointer(), + Operand(kIntSize)); + __ bind(&backtrack_non_equal); + BranchOrBacktrack(on_equal, eq, current_input_offset(), Operand(a0)); +} + + +void RegExpMacroAssemblerMIPS::CheckNotBackReferenceIgnoreCase( + int start_reg, + Label* on_no_match) { + Label fallthrough; + __ ld(a0, register_location(start_reg)); // Index of start of capture. + __ ld(a1, register_location(start_reg + 1)); // Index of end of capture. + __ Dsubu(a1, a1, a0); // Length of capture. + + // If length is zero, either the capture is empty or it is not participating. + // In either case succeed immediately. + __ Branch(&fallthrough, eq, a1, Operand(zero_reg)); + + __ Daddu(t1, a1, current_input_offset()); + // Check that there are enough characters left in the input. + BranchOrBacktrack(on_no_match, gt, t1, Operand(zero_reg)); + + if (mode_ == ASCII) { + Label success; + Label fail; + Label loop_check; + + // a0 - offset of start of capture. + // a1 - length of capture. + __ Daddu(a0, a0, Operand(end_of_input_address())); + __ Daddu(a2, end_of_input_address(), Operand(current_input_offset())); + __ Daddu(a1, a0, Operand(a1)); + + // a0 - Address of start of capture. + // a1 - Address of end of capture. + // a2 - Address of current input position. + + Label loop; + __ bind(&loop); + __ lbu(a3, MemOperand(a0, 0)); + __ daddiu(a0, a0, char_size()); + __ lbu(a4, MemOperand(a2, 0)); + __ daddiu(a2, a2, char_size()); + + __ Branch(&loop_check, eq, a4, Operand(a3)); + + // Mismatch, try case-insensitive match (converting letters to lower-case). + __ Or(a3, a3, Operand(0x20)); // Convert capture character to lower-case. + __ Or(a4, a4, Operand(0x20)); // Also convert input character. + __ Branch(&fail, ne, a4, Operand(a3)); + __ Dsubu(a3, a3, Operand('a')); + __ Branch(&loop_check, ls, a3, Operand('z' - 'a')); + // Latin-1: Check for values in range [224,254] but not 247. + __ Dsubu(a3, a3, Operand(224 - 'a')); + // Weren't Latin-1 letters. + __ Branch(&fail, hi, a3, Operand(254 - 224)); + // Check for 247. + __ Branch(&fail, eq, a3, Operand(247 - 224)); + + __ bind(&loop_check); + __ Branch(&loop, lt, a0, Operand(a1)); + __ jmp(&success); + + __ bind(&fail); + GoTo(on_no_match); + + __ bind(&success); + // Compute new value of character position after the matched part. + __ Dsubu(current_input_offset(), a2, end_of_input_address()); + } else { + DCHECK(mode_ == UC16); + // Put regexp engine registers on stack. + RegList regexp_registers_to_retain = current_input_offset().bit() | + current_character().bit() | backtrack_stackpointer().bit(); + __ MultiPush(regexp_registers_to_retain); + + int argument_count = 4; + __ PrepareCallCFunction(argument_count, a2); + + // a0 - offset of start of capture. + // a1 - length of capture. + + // Put arguments into arguments registers. + // Parameters are + // a0: Address byte_offset1 - Address captured substring's start. + // a1: Address byte_offset2 - Address of current character position. + // a2: size_t byte_length - length of capture in bytes(!). + // a3: Isolate* isolate. + + // Address of start of capture. + __ Daddu(a0, a0, Operand(end_of_input_address())); + // Length of capture. + __ mov(a2, a1); + // Save length in callee-save register for use on return. + __ mov(s3, a1); + // Address of current input position. + __ Daddu(a1, current_input_offset(), Operand(end_of_input_address())); + // Isolate. + __ li(a3, Operand(ExternalReference::isolate_address(masm_->isolate()))); + + { + AllowExternalCallThatCantCauseGC scope(masm_); + ExternalReference function = + ExternalReference::re_case_insensitive_compare_uc16(masm_->isolate()); + __ CallCFunction(function, argument_count); + } + + // Restore regexp engine registers. + __ MultiPop(regexp_registers_to_retain); + __ li(code_pointer(), Operand(masm_->CodeObject()), CONSTANT_SIZE); + __ ld(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); + + // Check if function returned non-zero for success or zero for failure. + BranchOrBacktrack(on_no_match, eq, v0, Operand(zero_reg)); + // On success, increment position by length of capture. + __ Daddu(current_input_offset(), current_input_offset(), Operand(s3)); + } + + __ bind(&fallthrough); +} + + +void RegExpMacroAssemblerMIPS::CheckNotBackReference( + int start_reg, + Label* on_no_match) { + Label fallthrough; + Label success; + + // Find length of back-referenced capture. + __ ld(a0, register_location(start_reg)); + __ ld(a1, register_location(start_reg + 1)); + __ Dsubu(a1, a1, a0); // Length to check. + // Succeed on empty capture (including no capture). + __ Branch(&fallthrough, eq, a1, Operand(zero_reg)); + + __ Daddu(t1, a1, current_input_offset()); + // Check that there are enough characters left in the input. + BranchOrBacktrack(on_no_match, gt, t1, Operand(zero_reg)); + + // Compute pointers to match string and capture string. + __ Daddu(a0, a0, Operand(end_of_input_address())); + __ Daddu(a2, end_of_input_address(), Operand(current_input_offset())); + __ Daddu(a1, a1, Operand(a0)); + + Label loop; + __ bind(&loop); + if (mode_ == ASCII) { + __ lbu(a3, MemOperand(a0, 0)); + __ daddiu(a0, a0, char_size()); + __ lbu(a4, MemOperand(a2, 0)); + __ daddiu(a2, a2, char_size()); + } else { + DCHECK(mode_ == UC16); + __ lhu(a3, MemOperand(a0, 0)); + __ daddiu(a0, a0, char_size()); + __ lhu(a4, MemOperand(a2, 0)); + __ daddiu(a2, a2, char_size()); + } + BranchOrBacktrack(on_no_match, ne, a3, Operand(a4)); + __ Branch(&loop, lt, a0, Operand(a1)); + + // Move current character position to position after match. + __ Dsubu(current_input_offset(), a2, end_of_input_address()); + __ bind(&fallthrough); +} + + +void RegExpMacroAssemblerMIPS::CheckNotCharacter(uint32_t c, + Label* on_not_equal) { + BranchOrBacktrack(on_not_equal, ne, current_character(), Operand(c)); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacterAfterAnd(uint32_t c, + uint32_t mask, + Label* on_equal) { + __ And(a0, current_character(), Operand(mask)); + Operand rhs = (c == 0) ? Operand(zero_reg) : Operand(c); + BranchOrBacktrack(on_equal, eq, a0, rhs); +} + + +void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterAnd(uint32_t c, + uint32_t mask, + Label* on_not_equal) { + __ And(a0, current_character(), Operand(mask)); + Operand rhs = (c == 0) ? Operand(zero_reg) : Operand(c); + BranchOrBacktrack(on_not_equal, ne, a0, rhs); +} + + +void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterMinusAnd( + uc16 c, + uc16 minus, + uc16 mask, + Label* on_not_equal) { + DCHECK(minus < String::kMaxUtf16CodeUnit); + __ Dsubu(a0, current_character(), Operand(minus)); + __ And(a0, a0, Operand(mask)); + BranchOrBacktrack(on_not_equal, ne, a0, Operand(c)); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacterInRange( + uc16 from, + uc16 to, + Label* on_in_range) { + __ Dsubu(a0, current_character(), Operand(from)); + // Unsigned lower-or-same condition. + BranchOrBacktrack(on_in_range, ls, a0, Operand(to - from)); +} + + +void RegExpMacroAssemblerMIPS::CheckCharacterNotInRange( + uc16 from, + uc16 to, + Label* on_not_in_range) { + __ Dsubu(a0, current_character(), Operand(from)); + // Unsigned higher condition. + BranchOrBacktrack(on_not_in_range, hi, a0, Operand(to - from)); +} + + +void RegExpMacroAssemblerMIPS::CheckBitInTable( + Handle<ByteArray> table, + Label* on_bit_set) { + __ li(a0, Operand(table)); + if (mode_ != ASCII || kTableMask != String::kMaxOneByteCharCode) { + __ And(a1, current_character(), Operand(kTableSize - 1)); + __ Daddu(a0, a0, a1); + } else { + __ Daddu(a0, a0, current_character()); + } + + __ lbu(a0, FieldMemOperand(a0, ByteArray::kHeaderSize)); + BranchOrBacktrack(on_bit_set, ne, a0, Operand(zero_reg)); +} + + +bool RegExpMacroAssemblerMIPS::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_ == ASCII) { + // One byte space characters are '\t'..'\r', ' ' and \u00a0. + Label success; + __ Branch(&success, eq, current_character(), Operand(' ')); + // Check range 0x09..0x0d. + __ Dsubu(a0, current_character(), Operand('\t')); + __ Branch(&success, ls, a0, Operand('\r' - '\t')); + // \u00a0 (NBSP). + BranchOrBacktrack(on_no_match, ne, a0, Operand(0x00a0 - '\t')); + __ 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'). + __ Dsubu(a0, current_character(), Operand('0')); + BranchOrBacktrack(on_no_match, hi, a0, Operand('9' - '0')); + return true; + case 'D': + // Match non ASCII-digits. + __ Dsubu(a0, current_character(), Operand('0')); + BranchOrBacktrack(on_no_match, ls, a0, Operand('9' - '0')); + return true; + case '.': { + // Match non-newlines (not 0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029). + __ Xor(a0, current_character(), Operand(0x01)); + // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c. + __ Dsubu(a0, a0, Operand(0x0b)); + BranchOrBacktrack(on_no_match, ls, a0, Operand(0x0c - 0x0b)); + 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. + __ Dsubu(a0, a0, Operand(0x2028 - 0x0b)); + BranchOrBacktrack(on_no_match, ls, a0, Operand(1)); + } + return true; + } + case 'n': { + // Match newlines (0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029). + __ Xor(a0, current_character(), Operand(0x01)); + // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c. + __ Dsubu(a0, a0, Operand(0x0b)); + if (mode_ == ASCII) { + BranchOrBacktrack(on_no_match, hi, a0, Operand(0x0c - 0x0b)); + } else { + Label done; + BranchOrBacktrack(&done, ls, a0, Operand(0x0c - 0x0b)); + // Compare original value to 0x2028 and 0x2029, using the already + // computed (current_char ^ 0x01 - 0x0b). I.e., check for + // 0x201d (0x2028 - 0x0b) or 0x201e. + __ Dsubu(a0, a0, Operand(0x2028 - 0x0b)); + BranchOrBacktrack(on_no_match, hi, a0, Operand(1)); + __ bind(&done); + } + return true; + } + case 'w': { + if (mode_ != ASCII) { + // Table is 128 entries, so all ASCII characters can be tested. + BranchOrBacktrack(on_no_match, hi, current_character(), Operand('z')); + } + ExternalReference map = ExternalReference::re_word_character_map(); + __ li(a0, Operand(map)); + __ Daddu(a0, a0, current_character()); + __ lbu(a0, MemOperand(a0, 0)); + BranchOrBacktrack(on_no_match, eq, a0, Operand(zero_reg)); + return true; + } + case 'W': { + Label done; + if (mode_ != ASCII) { + // Table is 128 entries, so all ASCII characters can be tested. + __ Branch(&done, hi, current_character(), Operand('z')); + } + ExternalReference map = ExternalReference::re_word_character_map(); + __ li(a0, Operand(map)); + __ Daddu(a0, a0, current_character()); + __ lbu(a0, MemOperand(a0, 0)); + BranchOrBacktrack(on_no_match, ne, a0, Operand(zero_reg)); + if (mode_ != ASCII) { + __ bind(&done); + } + return true; + } + case '*': + // Match any character. + return true; + // No custom implementation (yet): s(UC16), S(UC16). + default: + return false; + } +} + + +void RegExpMacroAssemblerMIPS::Fail() { + __ li(v0, Operand(FAILURE)); + __ jmp(&exit_label_); +} + + +Handle<HeapObject> RegExpMacroAssemblerMIPS::GetCode(Handle<String> source) { + Label return_v0; + if (masm_->has_exception()) { + // If the code gets corrupted due to long regular expressions and lack of + // space on trampolines, an internal exception flag is set. If this case + // is detected, we will jump into exit sequence right away. + __ bind_to(&entry_label_, internal_failure_label_.pos()); + } else { + // 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 is generated. + FrameScope scope(masm_, StackFrame::MANUAL); + + // Actually emit code to start a new stack frame. + // Push arguments + // Save callee-save registers. + // Start new stack frame. + // Store link register in existing stack-cell. + // Order here should correspond to order of offset constants in header file. + // TODO(plind): we save s0..s7, but ONLY use s3 here - use the regs + // or dont save. + RegList registers_to_retain = s0.bit() | s1.bit() | s2.bit() | + s3.bit() | s4.bit() | s5.bit() | s6.bit() | s7.bit() | fp.bit(); + RegList argument_registers = a0.bit() | a1.bit() | a2.bit() | a3.bit(); + + if (kMipsAbi == kN64) { + // TODO(plind): Should probably alias a4-a7, for clarity. + argument_registers |= a4.bit() | a5.bit() | a6.bit() | a7.bit(); + } + + __ MultiPush(argument_registers | registers_to_retain | ra.bit()); + // Set frame pointer in space for it if this is not a direct call + // from generated code. + // TODO(plind): this 8 is the # of argument regs, should have definition. + __ Daddu(frame_pointer(), sp, Operand(8 * kPointerSize)); + __ mov(a0, zero_reg); + __ push(a0); // Make room for success counter and initialize it to 0. + __ push(a0); // Make room for "position - 1" constant (value irrelevant). + + // Check if we have space on the stack for registers. + Label stack_limit_hit; + Label stack_ok; + + ExternalReference stack_limit = + ExternalReference::address_of_stack_limit(masm_->isolate()); + __ li(a0, Operand(stack_limit)); + __ ld(a0, MemOperand(a0)); + __ Dsubu(a0, sp, a0); + // Handle it if the stack pointer is already below the stack limit. + __ Branch(&stack_limit_hit, le, a0, Operand(zero_reg)); + // Check if there is room for the variable number of registers above + // the stack limit. + __ Branch(&stack_ok, hs, a0, Operand(num_registers_ * kPointerSize)); + // Exit with OutOfMemory exception. There is not enough space on the stack + // for our working registers. + __ li(v0, Operand(EXCEPTION)); + __ jmp(&return_v0); + + __ bind(&stack_limit_hit); + CallCheckStackGuardState(a0); + // If returned value is non-zero, we exit with the returned value as result. + __ Branch(&return_v0, ne, v0, Operand(zero_reg)); + + __ bind(&stack_ok); + // Allocate space on stack for registers. + __ Dsubu(sp, sp, Operand(num_registers_ * kPointerSize)); + // Load string end. + __ ld(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); + // Load input start. + __ ld(a0, MemOperand(frame_pointer(), kInputStart)); + // Find negative length (offset of start relative to end). + __ Dsubu(current_input_offset(), a0, end_of_input_address()); + // Set a0 to address of char before start of the input string + // (effectively string position -1). + __ ld(a1, MemOperand(frame_pointer(), kStartIndex)); + __ Dsubu(a0, current_input_offset(), Operand(char_size())); + __ dsll(t1, a1, (mode_ == UC16) ? 1 : 0); + __ Dsubu(a0, a0, t1); + // Store this value in a local variable, for use when clearing + // position registers. + __ sd(a0, MemOperand(frame_pointer(), kInputStartMinusOne)); + + // Initialize code pointer register + __ li(code_pointer(), Operand(masm_->CodeObject()), CONSTANT_SIZE); + + Label load_char_start_regexp, start_regexp; + // Load newline if index is at start, previous character otherwise. + __ Branch(&load_char_start_regexp, ne, a1, Operand(zero_reg)); + __ li(current_character(), Operand('\n')); + __ jmp(&start_regexp); + + // 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. + if (num_saved_registers_ > 8) { + // Address of register 0. + __ Daddu(a1, frame_pointer(), Operand(kRegisterZero)); + __ li(a2, Operand(num_saved_registers_)); + Label init_loop; + __ bind(&init_loop); + __ sd(a0, MemOperand(a1)); + __ Daddu(a1, a1, Operand(-kPointerSize)); + __ Dsubu(a2, a2, Operand(1)); + __ Branch(&init_loop, ne, a2, Operand(zero_reg)); + } else { + for (int i = 0; i < num_saved_registers_; i++) { + __ sd(a0, register_location(i)); + } + } + } + + // Initialize backtrack stack pointer. + __ ld(backtrack_stackpointer(), MemOperand(frame_pointer(), 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. + __ ld(a1, MemOperand(frame_pointer(), kInputStart)); + __ ld(a0, MemOperand(frame_pointer(), kRegisterOutput)); + __ ld(a2, MemOperand(frame_pointer(), kStartIndex)); + __ Dsubu(a1, end_of_input_address(), a1); + // a1 is length of input in bytes. + if (mode_ == UC16) { + __ dsrl(a1, a1, 1); + } + // a1 is length of input in characters. + __ Daddu(a1, a1, Operand(a2)); + // a1 is length of string in characters. + + DCHECK_EQ(0, num_saved_registers_ % 2); + // Always an even number of capture registers. This allows us to + // unroll the loop once to add an operation between a load of a register + // and the following use of that register. + for (int i = 0; i < num_saved_registers_; i += 2) { + __ ld(a2, register_location(i)); + __ ld(a3, register_location(i + 1)); + if (i == 0 && global_with_zero_length_check()) { + // Keep capture start in a4 for the zero-length check later. + __ mov(t3, a2); + } + if (mode_ == UC16) { + __ dsra(a2, a2, 1); + __ Daddu(a2, a2, a1); + __ dsra(a3, a3, 1); + __ Daddu(a3, a3, a1); + } else { + __ Daddu(a2, a1, Operand(a2)); + __ Daddu(a3, a1, Operand(a3)); + } + // V8 expects the output to be an int32_t array. + __ sw(a2, MemOperand(a0)); + __ Daddu(a0, a0, kIntSize); + __ sw(a3, MemOperand(a0)); + __ Daddu(a0, a0, kIntSize); + } + } + + if (global()) { + // Restart matching if the regular expression is flagged as global. + __ ld(a0, MemOperand(frame_pointer(), kSuccessfulCaptures)); + __ lw(a1, MemOperand(frame_pointer(), kNumOutputRegisters)); + __ ld(a2, MemOperand(frame_pointer(), kRegisterOutput)); + // Increment success counter. + __ Daddu(a0, a0, 1); + __ sd(a0, MemOperand(frame_pointer(), kSuccessfulCaptures)); + // Capture results have been stored, so the number of remaining global + // output registers is reduced by the number of stored captures. + __ Dsubu(a1, a1, num_saved_registers_); + // Check whether we have enough room for another set of capture results. + __ mov(v0, a0); + __ Branch(&return_v0, lt, a1, Operand(num_saved_registers_)); + + __ sd(a1, MemOperand(frame_pointer(), kNumOutputRegisters)); + // Advance the location for output. + __ Daddu(a2, a2, num_saved_registers_ * kIntSize); + __ sd(a2, MemOperand(frame_pointer(), kRegisterOutput)); + + // Prepare a0 to initialize registers with its value in the next run. + __ ld(a0, MemOperand(frame_pointer(), kInputStartMinusOne)); + + if (global_with_zero_length_check()) { + // Special case for zero-length matches. + // t3: capture start index + // Not a zero-length match, restart. + __ Branch( + &load_char_start_regexp, ne, current_input_offset(), Operand(t3)); + // Offset from the end is zero if we already reached the end. + __ Branch(&exit_label_, eq, current_input_offset(), + Operand(zero_reg)); + // Advance current position after a zero-length match. + __ Daddu(current_input_offset(), + current_input_offset(), + Operand((mode_ == UC16) ? 2 : 1)); + } + + __ Branch(&load_char_start_regexp); + } else { + __ li(v0, Operand(SUCCESS)); + } + } + // Exit and return v0. + __ bind(&exit_label_); + if (global()) { + __ ld(v0, MemOperand(frame_pointer(), kSuccessfulCaptures)); + } + + __ bind(&return_v0); + // Skip sp past regexp registers and local variables.. + __ mov(sp, frame_pointer()); + // Restore registers s0..s7 and return (restoring ra to pc). + __ MultiPop(registers_to_retain | ra.bit()); + __ Ret(); + + // 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_); + // Put regexp engine registers on stack. + RegList regexp_registers_to_retain = current_input_offset().bit() | + current_character().bit() | backtrack_stackpointer().bit(); + __ MultiPush(regexp_registers_to_retain); + CallCheckStackGuardState(a0); + __ MultiPop(regexp_registers_to_retain); + // If returning non-zero, we should end execution with the given + // result as return value. + __ Branch(&return_v0, ne, v0, Operand(zero_reg)); + + // String might have moved: Reload end of string from frame. + __ ld(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); + __ li(code_pointer(), Operand(masm_->CodeObject()), CONSTANT_SIZE); + SafeReturn(); + } + + // Backtrack stack overflow code. + if (stack_overflow_label_.is_linked()) { + SafeCallTarget(&stack_overflow_label_); + // Reached if the backtrack-stack limit has been hit. + // Put regexp engine registers on stack first. + RegList regexp_registers = current_input_offset().bit() | + current_character().bit(); + __ MultiPush(regexp_registers); + Label grow_failed; + // Call GrowStack(backtrack_stackpointer(), &stack_base) + static const int num_arguments = 3; + __ PrepareCallCFunction(num_arguments, a0); + __ mov(a0, backtrack_stackpointer()); + __ Daddu(a1, frame_pointer(), Operand(kStackHighEnd)); + __ li(a2, Operand(ExternalReference::isolate_address(masm_->isolate()))); + ExternalReference grow_stack = + ExternalReference::re_grow_stack(masm_->isolate()); + __ CallCFunction(grow_stack, num_arguments); + // Restore regexp registers. + __ MultiPop(regexp_registers); + // If return NULL, we have failed to grow the stack, and + // must exit with a stack-overflow exception. + __ Branch(&exit_with_exception, eq, v0, Operand(zero_reg)); + // Otherwise use return value as new stack pointer. + __ mov(backtrack_stackpointer(), v0); + // Restore saved registers and continue. + __ li(code_pointer(), Operand(masm_->CodeObject()), CONSTANT_SIZE); + __ ld(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); + 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. + __ li(v0, Operand(EXCEPTION)); + __ jmp(&return_v0); + } + } + + CodeDesc code_desc; + masm_->GetCode(&code_desc); + Handle<Code> code = isolate()->factory()->NewCode( + code_desc, Code::ComputeFlags(Code::REGEXP), masm_->CodeObject()); + LOG(masm_->isolate(), RegExpCodeCreateEvent(*code, *source)); + return Handle<HeapObject>::cast(code); +} + + +void RegExpMacroAssemblerMIPS::GoTo(Label* to) { + if (to == NULL) { + Backtrack(); + return; + } + __ jmp(to); + return; +} + + +void RegExpMacroAssemblerMIPS::IfRegisterGE(int reg, + int comparand, + Label* if_ge) { + __ ld(a0, register_location(reg)); + BranchOrBacktrack(if_ge, ge, a0, Operand(comparand)); +} + + +void RegExpMacroAssemblerMIPS::IfRegisterLT(int reg, + int comparand, + Label* if_lt) { + __ ld(a0, register_location(reg)); + BranchOrBacktrack(if_lt, lt, a0, Operand(comparand)); +} + + +void RegExpMacroAssemblerMIPS::IfRegisterEqPos(int reg, + Label* if_eq) { + __ ld(a0, register_location(reg)); + BranchOrBacktrack(if_eq, eq, a0, Operand(current_input_offset())); +} + + +RegExpMacroAssembler::IrregexpImplementation + RegExpMacroAssemblerMIPS::Implementation() { + return kMIPSImplementation; +} + + +void RegExpMacroAssemblerMIPS::LoadCurrentCharacter(int cp_offset, + Label* on_end_of_input, + bool check_bounds, + int characters) { + DCHECK(cp_offset >= -1); // ^ and \b can look behind one character. + DCHECK(cp_offset < (1<<30)); // Be sane! (And ensure negation works). + if (check_bounds) { + CheckPosition(cp_offset + characters - 1, on_end_of_input); + } + LoadCurrentCharacterUnchecked(cp_offset, characters); +} + + +void RegExpMacroAssemblerMIPS::PopCurrentPosition() { + Pop(current_input_offset()); +} + + +void RegExpMacroAssemblerMIPS::PopRegister(int register_index) { + Pop(a0); + __ sd(a0, register_location(register_index)); +} + + +void RegExpMacroAssemblerMIPS::PushBacktrack(Label* label) { + if (label->is_bound()) { + int target = label->pos(); + __ li(a0, Operand(target + Code::kHeaderSize - kHeapObjectTag)); + } else { + Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_); + Label after_constant; + __ Branch(&after_constant); + int offset = masm_->pc_offset(); + int cp_offset = offset + Code::kHeaderSize - kHeapObjectTag; + __ emit(0); + masm_->label_at_put(label, offset); + __ bind(&after_constant); + if (is_int16(cp_offset)) { + __ lwu(a0, MemOperand(code_pointer(), cp_offset)); + } else { + __ Daddu(a0, code_pointer(), cp_offset); + __ lwu(a0, MemOperand(a0, 0)); + } + } + Push(a0); + CheckStackLimit(); +} + + +void RegExpMacroAssemblerMIPS::PushCurrentPosition() { + Push(current_input_offset()); +} + + +void RegExpMacroAssemblerMIPS::PushRegister(int register_index, + StackCheckFlag check_stack_limit) { + __ ld(a0, register_location(register_index)); + Push(a0); + if (check_stack_limit) CheckStackLimit(); +} + + +void RegExpMacroAssemblerMIPS::ReadCurrentPositionFromRegister(int reg) { + __ ld(current_input_offset(), register_location(reg)); +} + + +void RegExpMacroAssemblerMIPS::ReadStackPointerFromRegister(int reg) { + __ ld(backtrack_stackpointer(), register_location(reg)); + __ ld(a0, MemOperand(frame_pointer(), kStackHighEnd)); + __ Daddu(backtrack_stackpointer(), backtrack_stackpointer(), Operand(a0)); +} + + +void RegExpMacroAssemblerMIPS::SetCurrentPositionFromEnd(int by) { + Label after_position; + __ Branch(&after_position, + ge, + current_input_offset(), + Operand(-by * char_size())); + __ li(current_input_offset(), -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 RegExpMacroAssemblerMIPS::SetRegister(int register_index, int to) { + DCHECK(register_index >= num_saved_registers_); // Reserved for positions! + __ li(a0, Operand(to)); + __ sd(a0, register_location(register_index)); +} + + +bool RegExpMacroAssemblerMIPS::Succeed() { + __ jmp(&success_label_); + return global(); +} + + +void RegExpMacroAssemblerMIPS::WriteCurrentPositionToRegister(int reg, + int cp_offset) { + if (cp_offset == 0) { + __ sd(current_input_offset(), register_location(reg)); + } else { + __ Daddu(a0, current_input_offset(), Operand(cp_offset * char_size())); + __ sd(a0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerMIPS::ClearRegisters(int reg_from, int reg_to) { + DCHECK(reg_from <= reg_to); + __ ld(a0, MemOperand(frame_pointer(), kInputStartMinusOne)); + for (int reg = reg_from; reg <= reg_to; reg++) { + __ sd(a0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerMIPS::WriteStackPointerToRegister(int reg) { + __ ld(a1, MemOperand(frame_pointer(), kStackHighEnd)); + __ Dsubu(a0, backtrack_stackpointer(), a1); + __ sd(a0, register_location(reg)); +} + + +bool RegExpMacroAssemblerMIPS::CanReadUnaligned() { + return false; +} + + +// Private methods: + +void RegExpMacroAssemblerMIPS::CallCheckStackGuardState(Register scratch) { + int stack_alignment = base::OS::ActivationFrameAlignment(); + + // Align the stack pointer and save the original sp value on the stack. + __ mov(scratch, sp); + __ Dsubu(sp, sp, Operand(kPointerSize)); + DCHECK(IsPowerOf2(stack_alignment)); + __ And(sp, sp, Operand(-stack_alignment)); + __ sd(scratch, MemOperand(sp)); + + __ mov(a2, frame_pointer()); + // Code* of self. + __ li(a1, Operand(masm_->CodeObject()), CONSTANT_SIZE); + + // We need to make room for the return address on the stack. + DCHECK(IsAligned(stack_alignment, kPointerSize)); + __ Dsubu(sp, sp, Operand(stack_alignment)); + + // Stack pointer now points to cell where return address is to be written. + // Arguments are in registers, meaning we teat the return address as + // argument 5. Since DirectCEntryStub will handleallocating space for the C + // argument slots, we don't need to care about that here. This is how the + // stack will look (sp meaning the value of sp at this moment): + // [sp + 3] - empty slot if needed for alignment. + // [sp + 2] - saved sp. + // [sp + 1] - second word reserved for return value. + // [sp + 0] - first word reserved for return value. + + // a0 will point to the return address, placed by DirectCEntry. + __ mov(a0, sp); + + ExternalReference stack_guard_check = + ExternalReference::re_check_stack_guard_state(masm_->isolate()); + __ li(t9, Operand(stack_guard_check)); + DirectCEntryStub stub(isolate()); + stub.GenerateCall(masm_, t9); + + // DirectCEntryStub allocated space for the C argument slots so we have to + // drop them with the return address from the stack with loading saved sp. + // At this point stack must look: + // [sp + 7] - empty slot if needed for alignment. + // [sp + 6] - saved sp. + // [sp + 5] - second word reserved for return value. + // [sp + 4] - first word reserved for return value. + // [sp + 3] - C argument slot. + // [sp + 2] - C argument slot. + // [sp + 1] - C argument slot. + // [sp + 0] - C argument slot. + __ ld(sp, MemOperand(sp, stack_alignment + kCArgsSlotsSize)); + + __ li(code_pointer(), Operand(masm_->CodeObject())); +} + + +// Helper function for reading a value out of a stack frame. +template <typename T> +static T& frame_entry(Address re_frame, int frame_offset) { + return reinterpret_cast<T&>(Memory::int32_at(re_frame + frame_offset)); +} + + +int RegExpMacroAssemblerMIPS::CheckStackGuardState(Address* return_address, + Code* re_code, + Address re_frame) { + Isolate* isolate = frame_entry<Isolate*>(re_frame, kIsolate); + StackLimitCheck check(isolate); + if (check.JsHasOverflowed()) { + isolate->StackOverflow(); + return EXCEPTION; + } + + // If not real stack overflow the stack guard was used to interrupt + // execution for another purpose. + + // If this is a direct call from JavaScript retry the RegExp forcing the call + // through the runtime system. Currently the direct call cannot handle a GC. + if (frame_entry<int>(re_frame, kDirectCall) == 1) { + return RETRY; + } + + // Prepare for possible GC. + HandleScope handles(isolate); + Handle<Code> code_handle(re_code); + + Handle<String> subject(frame_entry<String*>(re_frame, kInputString)); + // Current string. + bool is_ascii = subject->IsOneByteRepresentationUnderneath(); + + DCHECK(re_code->instruction_start() <= *return_address); + DCHECK(*return_address <= + re_code->instruction_start() + re_code->instruction_size()); + + Object* result = isolate->stack_guard()->HandleInterrupts(); + + if (*code_handle != re_code) { // Return address no longer valid. + int delta = code_handle->address() - re_code->address(); + // Overwrite the return address on the stack. + *return_address += delta; + } + + if (result->IsException()) { + return EXCEPTION; + } + + Handle<String> subject_tmp = subject; + int slice_offset = 0; + + // Extract the underlying string and the slice offset. + if (StringShape(*subject_tmp).IsCons()) { + subject_tmp = Handle<String>(ConsString::cast(*subject_tmp)->first()); + } else if (StringShape(*subject_tmp).IsSliced()) { + SlicedString* slice = SlicedString::cast(*subject_tmp); + subject_tmp = Handle<String>(slice->parent()); + slice_offset = slice->offset(); + } + + // String might have changed. + if (subject_tmp->IsOneByteRepresentation() != is_ascii) { + // If we changed between an ASCII and an UC16 string, the specialized + // code cannot be used, and we need to restart regexp matching from + // scratch (including, potentially, compiling a new version of the code). + return RETRY; + } + + // Otherwise, the content of the string might have moved. It must still + // be a sequential or external string with the same content. + // Update the start and end pointers in the stack frame to the current + // location (whether it has actually moved or not). + DCHECK(StringShape(*subject_tmp).IsSequential() || + StringShape(*subject_tmp).IsExternal()); + + // The original start address of the characters to match. + const byte* start_address = frame_entry<const byte*>(re_frame, kInputStart); + + // Find the current start address of the same character at the current string + // position. + int start_index = frame_entry<int>(re_frame, kStartIndex); + const byte* new_address = StringCharacterPosition(*subject_tmp, + start_index + slice_offset); + + if (start_address != new_address) { + // If there is a difference, update the object pointer and start and end + // addresses in the RegExp stack frame to match the new value. + const byte* end_address = frame_entry<const byte* >(re_frame, kInputEnd); + int byte_length = static_cast<int>(end_address - start_address); + frame_entry<const String*>(re_frame, kInputString) = *subject; + frame_entry<const byte*>(re_frame, kInputStart) = new_address; + frame_entry<const byte*>(re_frame, kInputEnd) = new_address + byte_length; + } else if (frame_entry<const String*>(re_frame, kInputString) != *subject) { + // Subject string might have been a ConsString that underwent + // short-circuiting during GC. That will not change start_address but + // will change pointer inside the subject handle. + frame_entry<const String*>(re_frame, kInputString) = *subject; + } + + return 0; +} + + +MemOperand RegExpMacroAssemblerMIPS::register_location(int register_index) { + DCHECK(register_index < (1<<30)); + if (num_registers_ <= register_index) { + num_registers_ = register_index + 1; + } + return MemOperand(frame_pointer(), + kRegisterZero - register_index * kPointerSize); +} + + +void RegExpMacroAssemblerMIPS::CheckPosition(int cp_offset, + Label* on_outside_input) { + BranchOrBacktrack(on_outside_input, + ge, + current_input_offset(), + Operand(-cp_offset * char_size())); +} + + +void RegExpMacroAssemblerMIPS::BranchOrBacktrack(Label* to, + Condition condition, + Register rs, + const Operand& rt) { + if (condition == al) { // Unconditional. + if (to == NULL) { + Backtrack(); + return; + } + __ jmp(to); + return; + } + if (to == NULL) { + __ Branch(&backtrack_label_, condition, rs, rt); + return; + } + __ Branch(to, condition, rs, rt); +} + + +void RegExpMacroAssemblerMIPS::SafeCall(Label* to, + Condition cond, + Register rs, + const Operand& rt) { + __ BranchAndLink(to, cond, rs, rt); +} + + +void RegExpMacroAssemblerMIPS::SafeReturn() { + __ pop(ra); + __ Daddu(t1, ra, Operand(masm_->CodeObject())); + __ Jump(t1); +} + + +void RegExpMacroAssemblerMIPS::SafeCallTarget(Label* name) { + __ bind(name); + __ Dsubu(ra, ra, Operand(masm_->CodeObject())); + __ push(ra); +} + + +void RegExpMacroAssemblerMIPS::Push(Register source) { + DCHECK(!source.is(backtrack_stackpointer())); + __ Daddu(backtrack_stackpointer(), + backtrack_stackpointer(), + Operand(-kIntSize)); + __ sw(source, MemOperand(backtrack_stackpointer())); +} + + +void RegExpMacroAssemblerMIPS::Pop(Register target) { + DCHECK(!target.is(backtrack_stackpointer())); + __ lw(target, MemOperand(backtrack_stackpointer())); + __ Daddu(backtrack_stackpointer(), backtrack_stackpointer(), kIntSize); +} + + +void RegExpMacroAssemblerMIPS::CheckPreemption() { + // Check for preemption. + ExternalReference stack_limit = + ExternalReference::address_of_stack_limit(masm_->isolate()); + __ li(a0, Operand(stack_limit)); + __ ld(a0, MemOperand(a0)); + SafeCall(&check_preempt_label_, ls, sp, Operand(a0)); +} + + +void RegExpMacroAssemblerMIPS::CheckStackLimit() { + ExternalReference stack_limit = + ExternalReference::address_of_regexp_stack_limit(masm_->isolate()); + + __ li(a0, Operand(stack_limit)); + __ ld(a0, MemOperand(a0)); + SafeCall(&stack_overflow_label_, ls, backtrack_stackpointer(), Operand(a0)); +} + + +void RegExpMacroAssemblerMIPS::LoadCurrentCharacterUnchecked(int cp_offset, + int characters) { + Register offset = current_input_offset(); + if (cp_offset != 0) { + // t3 is not being used to store the capture start index at this point. + __ Daddu(t3, current_input_offset(), Operand(cp_offset * char_size())); + offset = t3; + } + // We assume that we cannot do unaligned loads on MIPS, so this function + // must only be used to load a single character at a time. + DCHECK(characters == 1); + __ Daddu(t1, end_of_input_address(), Operand(offset)); + if (mode_ == ASCII) { + __ lbu(current_character(), MemOperand(t1, 0)); + } else { + DCHECK(mode_ == UC16); + __ lhu(current_character(), MemOperand(t1, 0)); + } +} + +#undef __ + +#endif // V8_INTERPRETED_REGEXP + +}} // namespace v8::internal + +#endif // V8_TARGET_ARCH_MIPS64 |