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Diffstat (limited to 'src/3rdparty/v8/src/arm/regexp-macro-assembler-arm.cc')
| -rw-r--r-- | src/3rdparty/v8/src/arm/regexp-macro-assembler-arm.cc | 1287 |
1 files changed, 1287 insertions, 0 deletions
diff --git a/src/3rdparty/v8/src/arm/regexp-macro-assembler-arm.cc b/src/3rdparty/v8/src/arm/regexp-macro-assembler-arm.cc new file mode 100644 index 0000000..4bd8c80 --- /dev/null +++ b/src/3rdparty/v8/src/arm/regexp-macro-assembler-arm.cc @@ -0,0 +1,1287 @@ +// Copyright 2009 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "v8.h" + +#if defined(V8_TARGET_ARCH_ARM) + +#include "unicode.h" +#include "log.h" +#include "code-stubs.h" +#include "regexp-stack.h" +#include "macro-assembler.h" +#include "regexp-macro-assembler.h" +#include "arm/regexp-macro-assembler-arm.h" + +namespace v8 { +namespace internal { + +#ifndef V8_INTERPRETED_REGEXP +/* + * This assembler uses the following register assignment convention + * - r5 : Pointer to current code object (Code*) including heap object tag. + * - r6 : Current position in input, as negative offset from end of string. + * Please notice that this is the byte offset, not the character offset! + * - r7 : Currently loaded character. Must be loaded using + * LoadCurrentCharacter before using any of the dispatch methods. + * - r8 : points to tip of backtrack stack + * - r9 : Unused, might be used by C code and expected unchanged. + * - r10 : End of input (points to byte after last character in input). + * - r11 : Frame pointer. Used to access arguments, local variables and + * RegExp registers. + * - r12 : IP register, used by assembler. Very volatile. + * - r13/sp : points to tip of C stack. + * + * The remaining registers are free for computations. + * Each call to a public method should retain this convention. + * + * The stack will have the following structure: + * - fp[52] Isolate* isolate (Address of the current isolate) + * - fp[48] direct_call (if 1, direct call from JavaScript code, + * if 0, call through the runtime system). + * - fp[44] stack_area_base (High end of the memory area to use as + * backtracking stack). + * - fp[40] int* capture_array (int[num_saved_registers_], for output). + * - fp[36] secondary link/return address used by native call. + * --- sp when called --- + * - fp[32] return address (lr). + * - fp[28] old frame pointer (r11). + * - fp[0..24] backup of registers r4..r10. + * --- 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] Offset of location before start of input (effectively character + * position -1). Used to initialize capture registers to a + * non-position. + * - fp[-24] At start (if 1, we are starting at the start of the + * string, otherwise 0) + * - fp[-28] register 0 (Only positions must be stored in the first + * - 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) + * The call is performed by NativeRegExpMacroAssembler::Execute() + * (in regexp-macro-assembler.cc) via the CALL_GENERATED_REGEXP_CODE macro + * in arm/simulator-arm.h. + * When calling as a non-direct call (i.e., from C++ code), the return address + * area is overwritten with the LR 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_) + +RegExpMacroAssemblerARM::RegExpMacroAssemblerARM( + Mode mode, + int registers_to_save) + : masm_(new MacroAssembler(Isolate::Current(), 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_() { + ASSERT_EQ(0, registers_to_save % 2); + __ jmp(&entry_label_); // We'll write the entry code later. + EmitBacktrackConstantPool(); + __ bind(&start_label_); // And then continue from here. +} + + +RegExpMacroAssemblerARM::~RegExpMacroAssemblerARM() { + 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 RegExpMacroAssemblerARM::stack_limit_slack() { + return RegExpStack::kStackLimitSlack; +} + + +void RegExpMacroAssemblerARM::AdvanceCurrentPosition(int by) { + if (by != 0) { + __ add(current_input_offset(), + current_input_offset(), Operand(by * char_size())); + } +} + + +void RegExpMacroAssemblerARM::AdvanceRegister(int reg, int by) { + ASSERT(reg >= 0); + ASSERT(reg < num_registers_); + if (by != 0) { + __ ldr(r0, register_location(reg)); + __ add(r0, r0, Operand(by)); + __ str(r0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerARM::Backtrack() { + CheckPreemption(); + // Pop Code* offset from backtrack stack, add Code* and jump to location. + Pop(r0); + __ add(pc, r0, Operand(code_pointer())); +} + + +void RegExpMacroAssemblerARM::Bind(Label* label) { + __ bind(label); +} + + +void RegExpMacroAssemblerARM::CheckCharacter(uint32_t c, Label* on_equal) { + __ cmp(current_character(), Operand(c)); + BranchOrBacktrack(eq, on_equal); +} + + +void RegExpMacroAssemblerARM::CheckCharacterGT(uc16 limit, Label* on_greater) { + __ cmp(current_character(), Operand(limit)); + BranchOrBacktrack(gt, on_greater); +} + + +void RegExpMacroAssemblerARM::CheckAtStart(Label* on_at_start) { + Label not_at_start; + // Did we start the match at the start of the string at all? + __ ldr(r0, MemOperand(frame_pointer(), kAtStart)); + __ cmp(r0, Operand(0, RelocInfo::NONE)); + BranchOrBacktrack(eq, ¬_at_start); + + // If we did, are we still at the start of the input? + __ ldr(r1, MemOperand(frame_pointer(), kInputStart)); + __ add(r0, end_of_input_address(), Operand(current_input_offset())); + __ cmp(r0, r1); + BranchOrBacktrack(eq, on_at_start); + __ bind(¬_at_start); +} + + +void RegExpMacroAssemblerARM::CheckNotAtStart(Label* on_not_at_start) { + // Did we start the match at the start of the string at all? + __ ldr(r0, MemOperand(frame_pointer(), kAtStart)); + __ cmp(r0, Operand(0, RelocInfo::NONE)); + BranchOrBacktrack(eq, on_not_at_start); + // If we did, are we still at the start of the input? + __ ldr(r1, MemOperand(frame_pointer(), kInputStart)); + __ add(r0, end_of_input_address(), Operand(current_input_offset())); + __ cmp(r0, r1); + BranchOrBacktrack(ne, on_not_at_start); +} + + +void RegExpMacroAssemblerARM::CheckCharacterLT(uc16 limit, Label* on_less) { + __ cmp(current_character(), Operand(limit)); + BranchOrBacktrack(lt, on_less); +} + + +void RegExpMacroAssemblerARM::CheckCharacters(Vector<const uc16> str, + int cp_offset, + Label* on_failure, + bool check_end_of_string) { + if (on_failure == NULL) { + // Instead of inlining a backtrack for each test, (re)use the global + // backtrack target. + on_failure = &backtrack_label_; + } + + if (check_end_of_string) { + // Is last character of required match inside string. + CheckPosition(cp_offset + str.length() - 1, on_failure); + } + + __ add(r0, end_of_input_address(), Operand(current_input_offset())); + if (cp_offset != 0) { + int byte_offset = cp_offset * char_size(); + __ add(r0, r0, Operand(byte_offset)); + } + + // r0 : Address of characters to match against str. + int stored_high_byte = 0; + for (int i = 0; i < str.length(); i++) { + if (mode_ == ASCII) { + __ ldrb(r1, MemOperand(r0, char_size(), PostIndex)); + ASSERT(str[i] <= String::kMaxAsciiCharCode); + __ cmp(r1, Operand(str[i])); + } else { + __ ldrh(r1, MemOperand(r0, char_size(), PostIndex)); + uc16 match_char = str[i]; + int match_high_byte = (match_char >> 8); + if (match_high_byte == 0) { + __ cmp(r1, Operand(str[i])); + } else { + if (match_high_byte != stored_high_byte) { + __ mov(r2, Operand(match_high_byte)); + stored_high_byte = match_high_byte; + } + __ add(r3, r2, Operand(match_char & 0xff)); + __ cmp(r1, r3); + } + } + BranchOrBacktrack(ne, on_failure); + } +} + + +void RegExpMacroAssemblerARM::CheckGreedyLoop(Label* on_equal) { + __ ldr(r0, MemOperand(backtrack_stackpointer(), 0)); + __ cmp(current_input_offset(), r0); + __ add(backtrack_stackpointer(), + backtrack_stackpointer(), Operand(kPointerSize), LeaveCC, eq); + BranchOrBacktrack(eq, on_equal); +} + + +void RegExpMacroAssemblerARM::CheckNotBackReferenceIgnoreCase( + int start_reg, + Label* on_no_match) { + Label fallthrough; + __ ldr(r0, register_location(start_reg)); // Index of start of capture + __ ldr(r1, register_location(start_reg + 1)); // Index of end of capture + __ sub(r1, r1, r0, SetCC); // Length of capture. + + // If length is zero, either the capture is empty or it is not participating. + // In either case succeed immediately. + __ b(eq, &fallthrough); + + // Check that there are enough characters left in the input. + __ cmn(r1, Operand(current_input_offset())); + BranchOrBacktrack(gt, on_no_match); + + if (mode_ == ASCII) { + Label success; + Label fail; + Label loop_check; + + // r0 - offset of start of capture + // r1 - length of capture + __ add(r0, r0, Operand(end_of_input_address())); + __ add(r2, end_of_input_address(), Operand(current_input_offset())); + __ add(r1, r0, Operand(r1)); + + // r0 - Address of start of capture. + // r1 - Address of end of capture + // r2 - Address of current input position. + + Label loop; + __ bind(&loop); + __ ldrb(r3, MemOperand(r0, char_size(), PostIndex)); + __ ldrb(r4, MemOperand(r2, char_size(), PostIndex)); + __ cmp(r4, r3); + __ b(eq, &loop_check); + + // Mismatch, try case-insensitive match (converting letters to lower-case). + __ orr(r3, r3, Operand(0x20)); // Convert capture character to lower-case. + __ orr(r4, r4, Operand(0x20)); // Also convert input character. + __ cmp(r4, r3); + __ b(ne, &fail); + __ sub(r3, r3, Operand('a')); + __ cmp(r3, Operand('z' - 'a')); // Is r3 a lowercase letter? + __ b(hi, &fail); + + + __ bind(&loop_check); + __ cmp(r0, r1); + __ b(lt, &loop); + __ jmp(&success); + + __ bind(&fail); + BranchOrBacktrack(al, on_no_match); + + __ bind(&success); + // Compute new value of character position after the matched part. + __ sub(current_input_offset(), r2, end_of_input_address()); + } else { + ASSERT(mode_ == UC16); + int argument_count = 4; + __ PrepareCallCFunction(argument_count, r2); + + // r0 - offset of start of capture + // r1 - length of capture + + // Put arguments into arguments registers. + // Parameters are + // r0: Address byte_offset1 - Address captured substring's start. + // r1: Address byte_offset2 - Address of current character position. + // r2: size_t byte_length - length of capture in bytes(!) + // r3: Isolate* isolate + + // Address of start of capture. + __ add(r0, r0, Operand(end_of_input_address())); + // Length of capture. + __ mov(r2, Operand(r1)); + // Save length in callee-save register for use on return. + __ mov(r4, Operand(r1)); + // Address of current input position. + __ add(r1, current_input_offset(), Operand(end_of_input_address())); + // Isolate. + __ mov(r3, Operand(ExternalReference::isolate_address())); + + ExternalReference function = + ExternalReference::re_case_insensitive_compare_uc16(masm_->isolate()); + __ CallCFunction(function, argument_count); + + // Check if function returned non-zero for success or zero for failure. + __ cmp(r0, Operand(0, RelocInfo::NONE)); + BranchOrBacktrack(eq, on_no_match); + // On success, increment position by length of capture. + __ add(current_input_offset(), current_input_offset(), Operand(r4)); + } + + __ bind(&fallthrough); +} + + +void RegExpMacroAssemblerARM::CheckNotBackReference( + int start_reg, + Label* on_no_match) { + Label fallthrough; + Label success; + + // Find length of back-referenced capture. + __ ldr(r0, register_location(start_reg)); + __ ldr(r1, register_location(start_reg + 1)); + __ sub(r1, r1, r0, SetCC); // Length to check. + // Succeed on empty capture (including no capture). + __ b(eq, &fallthrough); + + // Check that there are enough characters left in the input. + __ cmn(r1, Operand(current_input_offset())); + BranchOrBacktrack(gt, on_no_match); + + // Compute pointers to match string and capture string + __ add(r0, r0, Operand(end_of_input_address())); + __ add(r2, end_of_input_address(), Operand(current_input_offset())); + __ add(r1, r1, Operand(r0)); + + Label loop; + __ bind(&loop); + if (mode_ == ASCII) { + __ ldrb(r3, MemOperand(r0, char_size(), PostIndex)); + __ ldrb(r4, MemOperand(r2, char_size(), PostIndex)); + } else { + ASSERT(mode_ == UC16); + __ ldrh(r3, MemOperand(r0, char_size(), PostIndex)); + __ ldrh(r4, MemOperand(r2, char_size(), PostIndex)); + } + __ cmp(r3, r4); + BranchOrBacktrack(ne, on_no_match); + __ cmp(r0, r1); + __ b(lt, &loop); + + // Move current character position to position after match. + __ sub(current_input_offset(), r2, end_of_input_address()); + __ bind(&fallthrough); +} + + +void RegExpMacroAssemblerARM::CheckNotRegistersEqual(int reg1, + int reg2, + Label* on_not_equal) { + __ ldr(r0, register_location(reg1)); + __ ldr(r1, register_location(reg2)); + __ cmp(r0, r1); + BranchOrBacktrack(ne, on_not_equal); +} + + +void RegExpMacroAssemblerARM::CheckNotCharacter(unsigned c, + Label* on_not_equal) { + __ cmp(current_character(), Operand(c)); + BranchOrBacktrack(ne, on_not_equal); +} + + +void RegExpMacroAssemblerARM::CheckCharacterAfterAnd(uint32_t c, + uint32_t mask, + Label* on_equal) { + __ and_(r0, current_character(), Operand(mask)); + __ cmp(r0, Operand(c)); + BranchOrBacktrack(eq, on_equal); +} + + +void RegExpMacroAssemblerARM::CheckNotCharacterAfterAnd(unsigned c, + unsigned mask, + Label* on_not_equal) { + __ and_(r0, current_character(), Operand(mask)); + __ cmp(r0, Operand(c)); + BranchOrBacktrack(ne, on_not_equal); +} + + +void RegExpMacroAssemblerARM::CheckNotCharacterAfterMinusAnd( + uc16 c, + uc16 minus, + uc16 mask, + Label* on_not_equal) { + ASSERT(minus < String::kMaxUC16CharCode); + __ sub(r0, current_character(), Operand(minus)); + __ and_(r0, r0, Operand(mask)); + __ cmp(r0, Operand(c)); + BranchOrBacktrack(ne, on_not_equal); +} + + +bool RegExpMacroAssemblerARM::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) { + // ASCII space characters are '\t'..'\r' and ' '. + Label success; + __ cmp(current_character(), Operand(' ')); + __ b(eq, &success); + // Check range 0x09..0x0d + __ sub(r0, current_character(), Operand('\t')); + __ cmp(r0, Operand('\r' - '\t')); + BranchOrBacktrack(hi, on_no_match); + __ bind(&success); + return true; + } + return false; + case 'S': + // Match non-space characters. + if (mode_ == ASCII) { + // ASCII space characters are '\t'..'\r' and ' '. + __ cmp(current_character(), Operand(' ')); + BranchOrBacktrack(eq, on_no_match); + __ sub(r0, current_character(), Operand('\t')); + __ cmp(r0, Operand('\r' - '\t')); + BranchOrBacktrack(ls, on_no_match); + return true; + } + return false; + case 'd': + // Match ASCII digits ('0'..'9') + __ sub(r0, current_character(), Operand('0')); + __ cmp(current_character(), Operand('9' - '0')); + BranchOrBacktrack(hi, on_no_match); + return true; + case 'D': + // Match non ASCII-digits + __ sub(r0, current_character(), Operand('0')); + __ cmp(r0, Operand('9' - '0')); + BranchOrBacktrack(ls, on_no_match); + return true; + case '.': { + // Match non-newlines (not 0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029) + __ eor(r0, current_character(), Operand(0x01)); + // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c + __ sub(r0, r0, Operand(0x0b)); + __ cmp(r0, Operand(0x0c - 0x0b)); + BranchOrBacktrack(ls, 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(r0, r0, Operand(0x2028 - 0x0b)); + __ cmp(r0, Operand(1)); + BranchOrBacktrack(ls, on_no_match); + } + return true; + } + case 'n': { + // Match newlines (0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029) + __ eor(r0, current_character(), Operand(0x01)); + // See if current character is '\n'^1 or '\r'^1, i.e., 0x0b or 0x0c + __ sub(r0, r0, Operand(0x0b)); + __ cmp(r0, Operand(0x0c - 0x0b)); + if (mode_ == ASCII) { + BranchOrBacktrack(hi, on_no_match); + } else { + Label done; + __ b(ls, &done); + // 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(r0, r0, Operand(0x2028 - 0x0b)); + __ cmp(r0, Operand(1)); + BranchOrBacktrack(hi, on_no_match); + __ bind(&done); + } + return true; + } + case 'w': { + if (mode_ != ASCII) { + // Table is 128 entries, so all ASCII characters can be tested. + __ cmp(current_character(), Operand('z')); + BranchOrBacktrack(hi, on_no_match); + } + ExternalReference map = ExternalReference::re_word_character_map(); + __ mov(r0, Operand(map)); + __ ldrb(r0, MemOperand(r0, current_character())); + __ tst(r0, Operand(r0)); + BranchOrBacktrack(eq, on_no_match); + return true; + } + case 'W': { + Label done; + if (mode_ != ASCII) { + // Table is 128 entries, so all ASCII characters can be tested. + __ cmp(current_character(), Operand('z')); + __ b(hi, &done); + } + ExternalReference map = ExternalReference::re_word_character_map(); + __ mov(r0, Operand(map)); + __ ldrb(r0, MemOperand(r0, current_character())); + __ tst(r0, Operand(r0)); + BranchOrBacktrack(ne, on_no_match); + 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 RegExpMacroAssemblerARM::Fail() { + __ mov(r0, Operand(FAILURE)); + __ jmp(&exit_label_); +} + + +Handle<Object> RegExpMacroAssemblerARM::GetCode(Handle<String> source) { + // Finalize code - write the entry point code now we know how many + // registers we need. + + // Entry code: + __ bind(&entry_label_); + // 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. + RegList registers_to_retain = r4.bit() | r5.bit() | r6.bit() | + r7.bit() | r8.bit() | r9.bit() | r10.bit() | fp.bit(); + RegList argument_registers = r0.bit() | r1.bit() | r2.bit() | r3.bit(); + __ stm(db_w, sp, argument_registers | registers_to_retain | lr.bit()); + // Set frame pointer in space for it if this is not a direct call + // from generated code. + __ add(frame_pointer(), sp, Operand(4 * kPointerSize)); + __ push(r0); // Make room for "position - 1" constant (value is irrelevant). + __ push(r0); // Make room for "at start" constant (value is 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()); + __ mov(r0, Operand(stack_limit)); + __ ldr(r0, MemOperand(r0)); + __ sub(r0, sp, r0, SetCC); + // Handle it if the stack pointer is already below the stack limit. + __ b(ls, &stack_limit_hit); + // Check if there is room for the variable number of registers above + // the stack limit. + __ cmp(r0, Operand(num_registers_ * kPointerSize)); + __ b(hs, &stack_ok); + // Exit with OutOfMemory exception. There is not enough space on the stack + // for our working registers. + __ mov(r0, Operand(EXCEPTION)); + __ jmp(&exit_label_); + + __ bind(&stack_limit_hit); + CallCheckStackGuardState(r0); + __ cmp(r0, Operand(0, RelocInfo::NONE)); + // If returned value is non-zero, we exit with the returned value as result. + __ b(ne, &exit_label_); + + __ bind(&stack_ok); + + // Allocate space on stack for registers. + __ sub(sp, sp, Operand(num_registers_ * kPointerSize)); + // Load string end. + __ ldr(end_of_input_address(), MemOperand(frame_pointer(), kInputEnd)); + // Load input start. + __ ldr(r0, MemOperand(frame_pointer(), kInputStart)); + // Find negative length (offset of start relative to end). + __ sub(current_input_offset(), r0, end_of_input_address()); + // Set r0 to address of char before start of the input string + // (effectively string position -1). + __ ldr(r1, MemOperand(frame_pointer(), kStartIndex)); + __ sub(r0, current_input_offset(), Operand(char_size())); + __ sub(r0, r0, Operand(r1, LSL, (mode_ == UC16) ? 1 : 0)); + // Store this value in a local variable, for use when clearing + // position registers. + __ str(r0, MemOperand(frame_pointer(), kInputStartMinusOne)); + + // Determine whether the start index is zero, that is at the start of the + // string, and store that value in a local variable. + __ tst(r1, Operand(r1)); + __ mov(r1, Operand(1), LeaveCC, eq); + __ mov(r1, Operand(0, RelocInfo::NONE), LeaveCC, ne); + __ str(r1, MemOperand(frame_pointer(), kAtStart)); + + if (num_saved_registers_ > 0) { // Always is, if generated from a regexp. + // Fill saved registers with initial value = start offset - 1 + + // Address of register 0. + __ add(r1, frame_pointer(), Operand(kRegisterZero)); + __ mov(r2, Operand(num_saved_registers_)); + Label init_loop; + __ bind(&init_loop); + __ str(r0, MemOperand(r1, kPointerSize, NegPostIndex)); + __ sub(r2, r2, Operand(1), SetCC); + __ b(ne, &init_loop); + } + + // Initialize backtrack stack pointer. + __ ldr(backtrack_stackpointer(), MemOperand(frame_pointer(), kStackHighEnd)); + // Initialize code pointer register + __ mov(code_pointer(), Operand(masm_->CodeObject())); + // Load previous char as initial value of current character register. + Label at_start; + __ ldr(r0, MemOperand(frame_pointer(), kAtStart)); + __ cmp(r0, Operand(0, RelocInfo::NONE)); + __ b(ne, &at_start); + LoadCurrentCharacterUnchecked(-1, 1); // Load previous char. + __ jmp(&start_label_); + __ bind(&at_start); + __ mov(current_character(), Operand('\n')); + __ 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 + __ ldr(r1, MemOperand(frame_pointer(), kInputStart)); + __ ldr(r0, MemOperand(frame_pointer(), kRegisterOutput)); + __ ldr(r2, MemOperand(frame_pointer(), kStartIndex)); + __ sub(r1, end_of_input_address(), r1); + // r1 is length of input in bytes. + if (mode_ == UC16) { + __ mov(r1, Operand(r1, LSR, 1)); + } + // r1 is length of input in characters. + __ add(r1, r1, Operand(r2)); + // r1 is length of string in characters. + + ASSERT_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) { + __ ldr(r2, register_location(i)); + __ ldr(r3, register_location(i + 1)); + if (mode_ == UC16) { + __ add(r2, r1, Operand(r2, ASR, 1)); + __ add(r3, r1, Operand(r3, ASR, 1)); + } else { + __ add(r2, r1, Operand(r2)); + __ add(r3, r1, Operand(r3)); + } + __ str(r2, MemOperand(r0, kPointerSize, PostIndex)); + __ str(r3, MemOperand(r0, kPointerSize, PostIndex)); + } + } + __ mov(r0, Operand(SUCCESS)); + } + // Exit and return r0 + __ bind(&exit_label_); + // Skip sp past regexp registers and local variables.. + __ mov(sp, frame_pointer()); + // Restore registers r4..r11 and return (restoring lr to pc). + __ ldm(ia_w, sp, registers_to_retain | pc.bit()); + + // 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_); + + CallCheckStackGuardState(r0); + __ cmp(r0, Operand(0, RelocInfo::NONE)); + // If returning non-zero, we should end execution with the given + // result as return value. + __ b(ne, &exit_label_); + + // String might have moved: Reload end of string from frame. + __ ldr(end_of_input_address(), MemOperand(frame_pointer(), 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. + Label grow_failed; + + // Call GrowStack(backtrack_stackpointer(), &stack_base) + static const int num_arguments = 3; + __ PrepareCallCFunction(num_arguments, r0); + __ mov(r0, backtrack_stackpointer()); + __ add(r1, frame_pointer(), Operand(kStackHighEnd)); + __ mov(r2, Operand(ExternalReference::isolate_address())); + ExternalReference grow_stack = + ExternalReference::re_grow_stack(masm_->isolate()); + __ CallCFunction(grow_stack, num_arguments); + // If return NULL, we have failed to grow the stack, and + // must exit with a stack-overflow exception. + __ cmp(r0, Operand(0, RelocInfo::NONE)); + __ b(eq, &exit_with_exception); + // Otherwise use return value as new stack pointer. + __ mov(backtrack_stackpointer(), r0); + // Restore saved registers and continue. + 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(r0, Operand(EXCEPTION)); + __ jmp(&exit_label_); + } + + CodeDesc code_desc; + masm_->GetCode(&code_desc); + Handle<Code> code = FACTORY->NewCode(code_desc, + Code::ComputeFlags(Code::REGEXP), + masm_->CodeObject()); + PROFILE(Isolate::Current(), RegExpCodeCreateEvent(*code, *source)); + return Handle<Object>::cast(code); +} + + +void RegExpMacroAssemblerARM::GoTo(Label* to) { + BranchOrBacktrack(al, to); +} + + +void RegExpMacroAssemblerARM::IfRegisterGE(int reg, + int comparand, + Label* if_ge) { + __ ldr(r0, register_location(reg)); + __ cmp(r0, Operand(comparand)); + BranchOrBacktrack(ge, if_ge); +} + + +void RegExpMacroAssemblerARM::IfRegisterLT(int reg, + int comparand, + Label* if_lt) { + __ ldr(r0, register_location(reg)); + __ cmp(r0, Operand(comparand)); + BranchOrBacktrack(lt, if_lt); +} + + +void RegExpMacroAssemblerARM::IfRegisterEqPos(int reg, + Label* if_eq) { + __ ldr(r0, register_location(reg)); + __ cmp(r0, Operand(current_input_offset())); + BranchOrBacktrack(eq, if_eq); +} + + +RegExpMacroAssembler::IrregexpImplementation + RegExpMacroAssemblerARM::Implementation() { + return kARMImplementation; +} + + +void RegExpMacroAssemblerARM::LoadCurrentCharacter(int cp_offset, + Label* on_end_of_input, + bool check_bounds, + int characters) { + ASSERT(cp_offset >= -1); // ^ and \b can look behind one character. + ASSERT(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 RegExpMacroAssemblerARM::PopCurrentPosition() { + Pop(current_input_offset()); +} + + +void RegExpMacroAssemblerARM::PopRegister(int register_index) { + Pop(r0); + __ str(r0, register_location(register_index)); +} + + +static bool is_valid_memory_offset(int value) { + if (value < 0) value = -value; + return value < (1<<12); +} + + +void RegExpMacroAssemblerARM::PushBacktrack(Label* label) { + if (label->is_bound()) { + int target = label->pos(); + __ mov(r0, Operand(target + Code::kHeaderSize - kHeapObjectTag)); + } else { + int constant_offset = GetBacktrackConstantPoolEntry(); + masm_->label_at_put(label, constant_offset); + // Reading pc-relative is based on the address 8 bytes ahead of + // the current opcode. + unsigned int offset_of_pc_register_read = + masm_->pc_offset() + Assembler::kPcLoadDelta; + int pc_offset_of_constant = + constant_offset - offset_of_pc_register_read; + ASSERT(pc_offset_of_constant < 0); + if (is_valid_memory_offset(pc_offset_of_constant)) { + masm_->BlockConstPoolBefore(masm_->pc_offset() + Assembler::kInstrSize); + __ ldr(r0, MemOperand(pc, pc_offset_of_constant)); + } else { + // Not a 12-bit offset, so it needs to be loaded from the constant + // pool. + masm_->BlockConstPoolBefore( + masm_->pc_offset() + 2 * Assembler::kInstrSize); + __ mov(r0, Operand(pc_offset_of_constant + Assembler::kInstrSize)); + __ ldr(r0, MemOperand(pc, r0)); + } + } + Push(r0); + CheckStackLimit(); +} + + +void RegExpMacroAssemblerARM::PushCurrentPosition() { + Push(current_input_offset()); +} + + +void RegExpMacroAssemblerARM::PushRegister(int register_index, + StackCheckFlag check_stack_limit) { + __ ldr(r0, register_location(register_index)); + Push(r0); + if (check_stack_limit) CheckStackLimit(); +} + + +void RegExpMacroAssemblerARM::ReadCurrentPositionFromRegister(int reg) { + __ ldr(current_input_offset(), register_location(reg)); +} + + +void RegExpMacroAssemblerARM::ReadStackPointerFromRegister(int reg) { + __ ldr(backtrack_stackpointer(), register_location(reg)); + __ ldr(r0, MemOperand(frame_pointer(), kStackHighEnd)); + __ add(backtrack_stackpointer(), backtrack_stackpointer(), Operand(r0)); +} + + +void RegExpMacroAssemblerARM::SetCurrentPositionFromEnd(int by) { + Label after_position; + __ cmp(current_input_offset(), Operand(-by * char_size())); + __ b(ge, &after_position); + __ mov(current_input_offset(), Operand(-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 RegExpMacroAssemblerARM::SetRegister(int register_index, int to) { + ASSERT(register_index >= num_saved_registers_); // Reserved for positions! + __ mov(r0, Operand(to)); + __ str(r0, register_location(register_index)); +} + + +void RegExpMacroAssemblerARM::Succeed() { + __ jmp(&success_label_); +} + + +void RegExpMacroAssemblerARM::WriteCurrentPositionToRegister(int reg, + int cp_offset) { + if (cp_offset == 0) { + __ str(current_input_offset(), register_location(reg)); + } else { + __ add(r0, current_input_offset(), Operand(cp_offset * char_size())); + __ str(r0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerARM::ClearRegisters(int reg_from, int reg_to) { + ASSERT(reg_from <= reg_to); + __ ldr(r0, MemOperand(frame_pointer(), kInputStartMinusOne)); + for (int reg = reg_from; reg <= reg_to; reg++) { + __ str(r0, register_location(reg)); + } +} + + +void RegExpMacroAssemblerARM::WriteStackPointerToRegister(int reg) { + __ ldr(r1, MemOperand(frame_pointer(), kStackHighEnd)); + __ sub(r0, backtrack_stackpointer(), r1); + __ str(r0, register_location(reg)); +} + + +// Private methods: + +void RegExpMacroAssemblerARM::CallCheckStackGuardState(Register scratch) { + static const int num_arguments = 3; + __ PrepareCallCFunction(num_arguments, scratch); + // RegExp code frame pointer. + __ mov(r2, frame_pointer()); + // Code* of self. + __ mov(r1, Operand(masm_->CodeObject())); + // r0 becomes return address pointer. + ExternalReference stack_guard_check = + ExternalReference::re_check_stack_guard_state(masm_->isolate()); + CallCFunctionUsingStub(stack_guard_check, num_arguments); +} + + +// 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 RegExpMacroAssemblerARM::CheckStackGuardState(Address* return_address, + Code* re_code, + Address re_frame) { + Isolate* isolate = frame_entry<Isolate*>(re_frame, kIsolate); + ASSERT(isolate == Isolate::Current()); + if (isolate->stack_guard()->IsStackOverflow()) { + 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; + Handle<Code> code_handle(re_code); + + Handle<String> subject(frame_entry<String*>(re_frame, kInputString)); + // Current string. + bool is_ascii = subject->IsAsciiRepresentation(); + + ASSERT(re_code->instruction_start() <= *return_address); + ASSERT(*return_address <= + re_code->instruction_start() + re_code->instruction_size()); + + MaybeObject* result = Execution::HandleStackGuardInterrupt(); + + if (*code_handle != re_code) { // Return address no longer valid + int delta = *code_handle - re_code; + // Overwrite the return address on the stack. + *return_address += delta; + } + + if (result->IsException()) { + return EXCEPTION; + } + + // String might have changed. + if (subject->IsAsciiRepresentation() != 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). + ASSERT(StringShape(*subject).IsSequential() || + StringShape(*subject).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, start_index); + + 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 = 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; + } + + return 0; +} + + +MemOperand RegExpMacroAssemblerARM::register_location(int register_index) { + ASSERT(register_index < (1<<30)); + if (num_registers_ <= register_index) { + num_registers_ = register_index + 1; + } + return MemOperand(frame_pointer(), + kRegisterZero - register_index * kPointerSize); +} + + +void RegExpMacroAssemblerARM::CheckPosition(int cp_offset, + Label* on_outside_input) { + __ cmp(current_input_offset(), Operand(-cp_offset * char_size())); + BranchOrBacktrack(ge, on_outside_input); +} + + +void RegExpMacroAssemblerARM::BranchOrBacktrack(Condition condition, + Label* to) { + if (condition == al) { // Unconditional. + if (to == NULL) { + Backtrack(); + return; + } + __ jmp(to); + return; + } + if (to == NULL) { + __ b(condition, &backtrack_label_); + return; + } + __ b(condition, to); +} + + +void RegExpMacroAssemblerARM::SafeCall(Label* to, Condition cond) { + __ bl(to, cond); +} + + +void RegExpMacroAssemblerARM::SafeReturn() { + __ pop(lr); + __ add(pc, lr, Operand(masm_->CodeObject())); +} + + +void RegExpMacroAssemblerARM::SafeCallTarget(Label* name) { + __ bind(name); + __ sub(lr, lr, Operand(masm_->CodeObject())); + __ push(lr); +} + + +void RegExpMacroAssemblerARM::Push(Register source) { + ASSERT(!source.is(backtrack_stackpointer())); + __ str(source, + MemOperand(backtrack_stackpointer(), kPointerSize, NegPreIndex)); +} + + +void RegExpMacroAssemblerARM::Pop(Register target) { + ASSERT(!target.is(backtrack_stackpointer())); + __ ldr(target, + MemOperand(backtrack_stackpointer(), kPointerSize, PostIndex)); +} + + +void RegExpMacroAssemblerARM::CheckPreemption() { + // Check for preemption. + ExternalReference stack_limit = + ExternalReference::address_of_stack_limit(masm_->isolate()); + __ mov(r0, Operand(stack_limit)); + __ ldr(r0, MemOperand(r0)); + __ cmp(sp, r0); + SafeCall(&check_preempt_label_, ls); +} + + +void RegExpMacroAssemblerARM::CheckStackLimit() { + ExternalReference stack_limit = + ExternalReference::address_of_regexp_stack_limit(masm_->isolate()); + __ mov(r0, Operand(stack_limit)); + __ ldr(r0, MemOperand(r0)); + __ cmp(backtrack_stackpointer(), Operand(r0)); + SafeCall(&stack_overflow_label_, ls); +} + + +void RegExpMacroAssemblerARM::EmitBacktrackConstantPool() { + __ CheckConstPool(false, false); + __ BlockConstPoolBefore( + masm_->pc_offset() + kBacktrackConstantPoolSize * Assembler::kInstrSize); + backtrack_constant_pool_offset_ = masm_->pc_offset(); + for (int i = 0; i < kBacktrackConstantPoolSize; i++) { + __ emit(0); + } + + backtrack_constant_pool_capacity_ = kBacktrackConstantPoolSize; +} + + +int RegExpMacroAssemblerARM::GetBacktrackConstantPoolEntry() { + while (backtrack_constant_pool_capacity_ > 0) { + int offset = backtrack_constant_pool_offset_; + backtrack_constant_pool_offset_ += kPointerSize; + backtrack_constant_pool_capacity_--; + if (masm_->pc_offset() - offset < 2 * KB) { + return offset; + } + } + Label new_pool_skip; + __ jmp(&new_pool_skip); + EmitBacktrackConstantPool(); + __ bind(&new_pool_skip); + int offset = backtrack_constant_pool_offset_; + backtrack_constant_pool_offset_ += kPointerSize; + backtrack_constant_pool_capacity_--; + return offset; +} + + +void RegExpMacroAssemblerARM::CallCFunctionUsingStub( + ExternalReference function, + int num_arguments) { + // Must pass all arguments in registers. The stub pushes on the stack. + ASSERT(num_arguments <= 4); + __ mov(code_pointer(), Operand(function)); + RegExpCEntryStub stub; + __ CallStub(&stub); + if (OS::ActivationFrameAlignment() != 0) { + __ ldr(sp, MemOperand(sp, 0)); + } + __ mov(code_pointer(), Operand(masm_->CodeObject())); +} + + +void RegExpMacroAssemblerARM::LoadCurrentCharacterUnchecked(int cp_offset, + int characters) { + Register offset = current_input_offset(); + if (cp_offset != 0) { + __ add(r0, current_input_offset(), Operand(cp_offset * char_size())); + offset = r0; + } + // The ldr, str, ldrh, strh instructions can do unaligned accesses, if the CPU + // and the operating system running on the target allow it. + // If unaligned load/stores are not supported then this function must only + // be used to load a single character at a time. +#if !V8_TARGET_CAN_READ_UNALIGNED + ASSERT(characters == 1); +#endif + + if (mode_ == ASCII) { + if (characters == 4) { + __ ldr(current_character(), MemOperand(end_of_input_address(), offset)); + } else if (characters == 2) { + __ ldrh(current_character(), MemOperand(end_of_input_address(), offset)); + } else { + ASSERT(characters == 1); + __ ldrb(current_character(), MemOperand(end_of_input_address(), offset)); + } + } else { + ASSERT(mode_ == UC16); + if (characters == 2) { + __ ldr(current_character(), MemOperand(end_of_input_address(), offset)); + } else { + ASSERT(characters == 1); + __ ldrh(current_character(), MemOperand(end_of_input_address(), offset)); + } + } +} + + +void RegExpCEntryStub::Generate(MacroAssembler* masm_) { + int stack_alignment = OS::ActivationFrameAlignment(); + if (stack_alignment < kPointerSize) stack_alignment = kPointerSize; + // Stack is already aligned for call, so decrement by alignment + // to make room for storing the link register. + __ str(lr, MemOperand(sp, stack_alignment, NegPreIndex)); + __ mov(r0, sp); + __ Call(r5); + __ ldr(pc, MemOperand(sp, stack_alignment, PostIndex)); +} + +#undef __ + +#endif // V8_INTERPRETED_REGEXP + +}} // namespace v8::internal + +#endif // V8_TARGET_ARCH_ARM |