| // Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #include "vm/regexp_assembler_ir.h" |
| |
| #include "vm/bit_vector.h" |
| #include "vm/compiler.h" |
| #include "vm/dart_entry.h" |
| #include "vm/flow_graph_builder.h" |
| #include "vm/il_printer.h" |
| #include "vm/object_store.h" |
| #include "vm/regexp.h" |
| #include "vm/resolver.h" |
| #include "vm/runtime_entry.h" |
| #include "vm/stack_frame.h" |
| #include "vm/unibrow-inl.h" |
| #include "vm/unicode.h" |
| |
| #define Z zone() |
| |
| // Debugging output macros. TAG() is called at the head of each interesting |
| // function and prints its name during execution if irregexp tracing is enabled. |
| #define TAG() if (FLAG_trace_irregexp) { TAG_(); } |
| #define TAG_() \ |
| Print(PushArgument( \ |
| Bind(new(Z) ConstantInstr(String::ZoneHandle(Z, String::Concat( \ |
| String::Handle(String::New("TAG: ")), \ |
| String::Handle(String::New(__FUNCTION__)), Heap::kOld)))))); |
| |
| #define PRINT(arg) if (FLAG_trace_irregexp) { Print(arg); } |
| |
| namespace dart { |
| |
| DEFINE_FLAG(bool, trace_irregexp, false, "Trace irregexps"); |
| |
| |
| static const intptr_t kInvalidTryIndex = CatchClauseNode::kInvalidTryIndex; |
| static const intptr_t kNoSourcePos = Scanner::kNoSourcePos; |
| static const intptr_t kMinStackSize = 512; |
| |
| |
| void PrintUtf16(uint16_t c) { |
| const char* format = (0x20 <= c && c <= 0x7F) ? |
| "%c" : (c <= 0xff) ? "\\x%02x" : "\\u%04x"; |
| OS::Print(format, c); |
| } |
| |
| |
| /* |
| * This assembler uses the following main local variables: |
| * - stack_: A pointer to a growable list which we use as an all-purpose stack |
| * storing backtracking offsets, positions & stored register values. |
| * - current_character_: Stores the currently loaded characters (possibly more |
| * than one). |
| * - current_position_: The current position within the string, stored as a |
| * negative offset from the end of the string (i.e. the |
| * position corresponding to str[0] is -str.length). |
| * Note that current_position_ is *not* byte-based, unlike |
| * original V8 code. |
| * |
| * Results are returned though an array of capture indices, stored at |
| * matches_param_. A null array specifies a failure to match. The match indices |
| * [start_inclusive, end_exclusive] for capture group i are stored at positions |
| * matches_param_[i * 2] and matches_param_[i * 2 + 1], respectively. Match |
| * indices of -1 denote non-matched groups. Note that we store these indices |
| * as a negative offset from the end of the string in registers_array_ |
| * during processing, and convert them to standard indexes when copying them |
| * to matches_param_ on successful match. |
| */ |
| IRRegExpMacroAssembler::IRRegExpMacroAssembler( |
| intptr_t specialization_cid, |
| intptr_t capture_count, |
| const ParsedFunction* parsed_function, |
| const ZoneGrowableArray<const ICData*>& ic_data_array, |
| Zone* zone) |
| : RegExpMacroAssembler(zone), |
| specialization_cid_(specialization_cid), |
| parsed_function_(parsed_function), |
| ic_data_array_(ic_data_array), |
| current_instruction_(NULL), |
| stack_(NULL), |
| stack_pointer_(NULL), |
| current_character_(NULL), |
| current_position_(NULL), |
| string_param_(NULL), |
| string_param_length_(NULL), |
| start_index_param_(NULL), |
| registers_count_(0), |
| saved_registers_count_((capture_count + 1) * 2), |
| stack_array_cell_(Array::ZoneHandle(zone, Array::New(1, Heap::kOld))), |
| // The registers array is allocated at a fixed size after assembly. |
| registers_array_(TypedData::ZoneHandle(zone, TypedData::null())) { |
| switch (specialization_cid) { |
| case kOneByteStringCid: |
| case kExternalOneByteStringCid: mode_ = ASCII; break; |
| case kTwoByteStringCid: |
| case kExternalTwoByteStringCid: mode_ = UC16; break; |
| default: UNREACHABLE(); |
| } |
| |
| InitializeLocals(); |
| |
| // Allocate an initial stack backing of the minimum stack size. The stack |
| // backing is indirectly referred to so we can reuse it on subsequent matches |
| // even in the case where the backing has been enlarged and thus reallocated. |
| stack_array_cell_.SetAt(0, TypedData::Handle(zone, |
| TypedData::New(kTypedDataInt32ArrayCid, kMinStackSize / 4, Heap::kOld))); |
| |
| // Create and generate all preset blocks. |
| entry_block_ = |
| new(zone) GraphEntryInstr( |
| *parsed_function_, |
| new(zone) TargetEntryInstr(block_id_.Alloc(), kInvalidTryIndex), |
| Thread::kNoDeoptId); |
| start_block_ = |
| new(zone) JoinEntryInstr(block_id_.Alloc(), kInvalidTryIndex); |
| success_block_ = |
| new(zone) JoinEntryInstr(block_id_.Alloc(), kInvalidTryIndex); |
| backtrack_block_ = |
| new(zone) JoinEntryInstr(block_id_.Alloc(), kInvalidTryIndex); |
| exit_block_ = |
| new(zone) JoinEntryInstr(block_id_.Alloc(), kInvalidTryIndex); |
| |
| GenerateEntryBlock(); |
| GenerateSuccessBlock(); |
| GenerateExitBlock(); |
| |
| blocks_.Add(entry_block_); |
| blocks_.Add(entry_block_->normal_entry()); |
| blocks_.Add(start_block_); |
| blocks_.Add(success_block_); |
| blocks_.Add(backtrack_block_); |
| blocks_.Add(exit_block_); |
| |
| // Begin emission at the start_block_. |
| set_current_instruction(start_block_); |
| } |
| |
| |
| IRRegExpMacroAssembler::~IRRegExpMacroAssembler() { } |
| |
| |
| void IRRegExpMacroAssembler::InitializeLocals() { |
| // All generated functions are expected to have a current-context variable. |
| // This variable is unused in irregexp functions. |
| parsed_function_->current_context_var()->set_index(GetNextLocalIndex()); |
| |
| // Create local variables and parameters. |
| stack_ = Local(Symbols::stack()); |
| stack_pointer_ = Local(Symbols::stack_pointer()); |
| registers_ = Local(Symbols::position_registers()); |
| current_character_ = Local(Symbols::current_character()); |
| current_position_ = Local(Symbols::current_position()); |
| string_param_length_ = Local(Symbols::string_param_length()); |
| capture_length_ = Local(Symbols::capture_length()); |
| match_start_index_ = Local(Symbols::match_start_index()); |
| capture_start_index_ = Local(Symbols::capture_start_index()); |
| match_end_index_ = Local(Symbols::match_end_index()); |
| char_in_capture_ = Local(Symbols::char_in_capture()); |
| char_in_match_ = Local(Symbols::char_in_match()); |
| index_temp_ = Local(Symbols::index_temp()); |
| result_ = Local(Symbols::result()); |
| |
| string_param_ = Parameter(Symbols::string_param(), |
| RegExpMacroAssembler::kParamStringIndex); |
| start_index_param_ = Parameter(Symbols::start_index_param(), |
| RegExpMacroAssembler::kParamStartOffsetIndex); |
| } |
| |
| |
| void IRRegExpMacroAssembler::GenerateEntryBlock() { |
| set_current_instruction(entry_block_->normal_entry()); |
| TAG(); |
| |
| // Store string.length. |
| PushArgumentInstr* string_push = PushLocal(string_param_); |
| |
| StoreLocal( |
| string_param_length_, |
| Bind(InstanceCall( |
| InstanceCallDescriptor( |
| String::ZoneHandle(Field::GetterSymbol(Symbols::Length()))), |
| string_push))); |
| |
| // Store (start_index - string.length) as the current position (since it's a |
| // negative offset from the end of the string). |
| PushArgumentInstr* start_index_push = PushLocal(start_index_param_); |
| PushArgumentInstr* length_push = PushLocal(string_param_length_); |
| |
| StoreLocal(current_position_, Bind(Sub(start_index_push, length_push))); |
| |
| // Generate a local list variable to represent "registers" and |
| // initialize capture registers (others remain garbage). |
| StoreLocal(registers_, Bind(new(Z) ConstantInstr(registers_array_))); |
| ClearRegisters(0, saved_registers_count_ - 1); |
| |
| // Generate a local list variable to represent the backtracking stack. |
| PushArgumentInstr* stack_cell_push = |
| PushArgument(Bind(new(Z) ConstantInstr(stack_array_cell_))); |
| StoreLocal(stack_, Bind(InstanceCall( |
| InstanceCallDescriptor::FromToken(Token::kINDEX), |
| stack_cell_push, |
| PushArgument(Bind(Uint64Constant(0)))))); |
| StoreLocal(stack_pointer_, Bind(Int64Constant(-1))); |
| |
| // Jump to the start block. |
| current_instruction_->Goto(start_block_); |
| } |
| |
| |
| void IRRegExpMacroAssembler::GenerateBacktrackBlock() { |
| set_current_instruction(backtrack_block_); |
| TAG(); |
| CheckPreemption(); |
| |
| const intptr_t entries_count = entry_block_->indirect_entries().length(); |
| |
| TypedData& offsets = TypedData::ZoneHandle(Z, |
| TypedData::New(kTypedDataInt32ArrayCid, entries_count, Heap::kOld)); |
| |
| PushArgumentInstr* block_offsets_push = |
| PushArgument(Bind(new(Z) ConstantInstr(offsets))); |
| PushArgumentInstr* block_id_push = PushArgument(Bind(PopStack())); |
| |
| Value* offset_value = |
| Bind(InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| block_offsets_push, |
| block_id_push)); |
| |
| backtrack_goto_ = new(Z) IndirectGotoInstr(&offsets, offset_value); |
| CloseBlockWith(backtrack_goto_); |
| |
| // Add an edge from the "indirect" goto to each of the targets. |
| for (intptr_t j = 0; j < entries_count; j++) { |
| backtrack_goto_->AddSuccessor( |
| TargetWithJoinGoto(entry_block_->indirect_entries().At(j))); |
| } |
| } |
| |
| |
| void IRRegExpMacroAssembler::GenerateSuccessBlock() { |
| set_current_instruction(success_block_); |
| TAG(); |
| |
| Value* type = Bind(new(Z) ConstantInstr( |
| TypeArguments::ZoneHandle(Z, TypeArguments::null()))); |
| Value* length = Bind(Uint64Constant(saved_registers_count_)); |
| Value* array = Bind(new(Z) CreateArrayInstr(kNoSourcePos, type, length)); |
| StoreLocal(result_, array); |
| |
| // Store captured offsets in the `matches` parameter. |
| for (intptr_t i = 0; i < saved_registers_count_; i++) { |
| PushArgumentInstr* matches_push = PushLocal(result_); |
| PushArgumentInstr* index_push = PushArgument(Bind(Uint64Constant(i))); |
| |
| // Convert negative offsets from the end of the string to string indices. |
| // TODO(zerny): use positive offsets from the get-go. |
| PushArgumentInstr* offset_push = PushArgument(LoadRegister(i)); |
| PushArgumentInstr* len_push = PushLocal(string_param_length_); |
| PushArgumentInstr* value_push = |
| PushArgument(Bind(Add(offset_push, len_push))); |
| |
| Do(InstanceCall(InstanceCallDescriptor::FromToken(Token::kASSIGN_INDEX), |
| matches_push, |
| index_push, |
| value_push)); |
| } |
| |
| // Print the result if tracing. |
| PRINT(PushLocal(result_)); |
| |
| // Return true on success. |
| AppendInstruction(new(Z) ReturnInstr(kNoSourcePos, Bind(LoadLocal(result_)))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::GenerateExitBlock() { |
| set_current_instruction(exit_block_); |
| TAG(); |
| |
| // Return false on failure. |
| AppendInstruction(new(Z) ReturnInstr(kNoSourcePos, Bind(LoadLocal(result_)))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::FinalizeRegistersArray() { |
| ASSERT(registers_count_ >= saved_registers_count_); |
| registers_array_ = |
| TypedData::New(kTypedDataInt32ArrayCid, registers_count_, Heap::kOld); |
| } |
| |
| |
| #if defined(TARGET_ARCH_ARM64) || \ |
| defined(TARGET_ARCH_ARM) || \ |
| defined(TARGET_ARCH_MIPS) |
| // Disabling unaligned accesses forces the regexp engine to load characters one |
| // by one instead of up to 4 at once, along with the associated performance hit. |
| // TODO(zerny): Be less conservative about disabling unaligned accesses. |
| // For instance, ARMv6 supports unaligned accesses. Once it is enabled here, |
| // update LoadCodeUnitsInstr methods for the appropriate architectures. |
| static const bool kEnableUnalignedAccesses = false; |
| #else |
| static const bool kEnableUnalignedAccesses = true; |
| #endif |
| bool IRRegExpMacroAssembler::CanReadUnaligned() { |
| return kEnableUnalignedAccesses && !slow_safe(); |
| } |
| |
| |
| RawArray* IRRegExpMacroAssembler::Execute( |
| const JSRegExp& regexp, |
| const String& input, |
| const Smi& start_offset, |
| Zone* zone) { |
| const intptr_t cid = input.GetClassId(); |
| const Function& fun = Function::Handle(regexp.function(cid)); |
| ASSERT(!fun.IsNull()); |
| // Create the argument list. |
| const Array& args = |
| Array::Handle(Array::New(RegExpMacroAssembler::kParamCount)); |
| args.SetAt(RegExpMacroAssembler::kParamRegExpIndex, regexp); |
| args.SetAt(RegExpMacroAssembler::kParamStringIndex, input); |
| args.SetAt(RegExpMacroAssembler::kParamStartOffsetIndex, start_offset); |
| |
| // And finally call the generated code. |
| |
| const Object& retval = |
| Object::Handle(zone, DartEntry::InvokeFunction(fun, args)); |
| if (retval.IsError()) { |
| const Error& error = Error::Cast(retval); |
| OS::Print("%s\n", error.ToErrorCString()); |
| // Should never happen. |
| UNREACHABLE(); |
| } |
| |
| if (retval.IsNull()) { |
| return Array::null(); |
| } |
| |
| ASSERT(retval.IsArray()); |
| return Array::Cast(retval).raw(); |
| } |
| |
| |
| static RawBool* CaseInsensitiveCompareUC16(RawString* str_raw, |
| RawSmi* lhs_index_raw, |
| RawSmi* rhs_index_raw, |
| RawSmi* length_raw) { |
| const String& str = String::Handle(str_raw); |
| const Smi& lhs_index = Smi::Handle(lhs_index_raw); |
| const Smi& rhs_index = Smi::Handle(rhs_index_raw); |
| const Smi& length = Smi::Handle(length_raw); |
| |
| // TODO(zerny): Optimize as single instance. V8 has this as an |
| // isolate member. |
| unibrow::Mapping<unibrow::Ecma262Canonicalize> canonicalize; |
| |
| for (intptr_t i = 0; i < length.Value(); i++) { |
| int32_t c1 = str.CharAt(lhs_index.Value() + i); |
| int32_t c2 = str.CharAt(rhs_index.Value() + i); |
| if (c1 != c2) { |
| int32_t s1[1] = { c1 }; |
| canonicalize.get(c1, '\0', s1); |
| if (s1[0] != c2) { |
| int32_t s2[1] = { c2 }; |
| canonicalize.get(c2, '\0', s2); |
| if (s1[0] != s2[0]) { |
| return Bool::False().raw(); |
| } |
| } |
| } |
| } |
| return Bool::True().raw(); |
| } |
| |
| |
| DEFINE_RAW_LEAF_RUNTIME_ENTRY( |
| CaseInsensitiveCompareUC16, 4, false /* is_float */, |
| reinterpret_cast<RuntimeFunction>(&CaseInsensitiveCompareUC16)); |
| |
| |
| LocalVariable* IRRegExpMacroAssembler::Parameter(const String& name, |
| intptr_t index) const { |
| const Type& local_type = Type::ZoneHandle(Z, Type::DynamicType()); |
| LocalVariable* local = |
| new(Z) LocalVariable(kNoSourcePos, name, local_type); |
| |
| intptr_t param_frame_index = kParamEndSlotFromFp + kParamCount - index; |
| local->set_index(param_frame_index); |
| |
| return local; |
| } |
| |
| |
| LocalVariable* IRRegExpMacroAssembler::Local(const String& name) { |
| const Type& local_type = Type::ZoneHandle(Z, Type::DynamicType()); |
| LocalVariable* local = |
| new(Z) LocalVariable(kNoSourcePos, name, local_type); |
| local->set_index(GetNextLocalIndex()); |
| |
| return local; |
| } |
| |
| |
| ConstantInstr* IRRegExpMacroAssembler::Int64Constant(int64_t value) const { |
| return new(Z) ConstantInstr( |
| Integer::ZoneHandle(Z, Integer::New(value, Heap::kOld))); |
| } |
| |
| |
| ConstantInstr* IRRegExpMacroAssembler::Uint64Constant(uint64_t value) const { |
| return new(Z) ConstantInstr( |
| Integer::ZoneHandle(Z, Integer::NewFromUint64(value, Heap::kOld))); |
| } |
| |
| |
| ConstantInstr* IRRegExpMacroAssembler::BoolConstant(bool value) const { |
| return new(Z) ConstantInstr(value ? Bool::True() : Bool::False()); |
| } |
| |
| |
| ConstantInstr* IRRegExpMacroAssembler::StringConstant(const char* value) const { |
| return new(Z) ConstantInstr( |
| String::ZoneHandle(Z, String::New(value, Heap::kOld))); |
| } |
| |
| |
| ConstantInstr* IRRegExpMacroAssembler::WordCharacterMapConstant() const { |
| const Library& lib = Library::Handle(Z, Library::CoreLibrary()); |
| const Class& regexp_class = Class::Handle(Z, |
| lib.LookupClassAllowPrivate(Symbols::JSSyntaxRegExp())); |
| const Field& word_character_field = Field::ZoneHandle(Z, |
| regexp_class.LookupStaticField(Symbols::_wordCharacterMap())); |
| ASSERT(!word_character_field.IsNull()); |
| |
| if (word_character_field.IsUninitialized()) { |
| word_character_field.EvaluateInitializer(); |
| } |
| ASSERT(!word_character_field.IsUninitialized()); |
| |
| return new(Z) ConstantInstr( |
| Instance::ZoneHandle(Z, word_character_field.StaticValue())); |
| } |
| |
| |
| ComparisonInstr* IRRegExpMacroAssembler::Comparison( |
| ComparisonKind kind, PushArgumentInstr* lhs, PushArgumentInstr* rhs) { |
| Token::Kind strict_comparison = Token::kEQ_STRICT; |
| Token::Kind intermediate_operator = Token::kILLEGAL; |
| switch (kind) { |
| case kEQ: |
| intermediate_operator = Token::kEQ; |
| break; |
| case kNE: |
| intermediate_operator = Token::kEQ; |
| strict_comparison = Token::kNE_STRICT; |
| break; |
| case kLT: |
| intermediate_operator = Token::kLT; |
| break; |
| case kGT: |
| intermediate_operator = Token::kGT; |
| break; |
| case kLTE: |
| intermediate_operator = Token::kLTE; |
| break; |
| case kGTE: |
| intermediate_operator = Token::kGTE; |
| break; |
| default: |
| UNREACHABLE(); |
| } |
| |
| ASSERT(intermediate_operator != Token::kILLEGAL); |
| |
| Value* lhs_value = |
| Bind(InstanceCall( |
| InstanceCallDescriptor::FromToken(intermediate_operator), |
| lhs, |
| rhs)); |
| Value* rhs_value = Bind(BoolConstant(true)); |
| |
| return new(Z) StrictCompareInstr( |
| kNoSourcePos, strict_comparison, lhs_value, rhs_value, true); |
| } |
| |
| ComparisonInstr* IRRegExpMacroAssembler::Comparison( |
| ComparisonKind kind, Definition* lhs, Definition* rhs) { |
| PushArgumentInstr* lhs_push = PushArgument(Bind(lhs)); |
| PushArgumentInstr* rhs_push = PushArgument(Bind(rhs)); |
| return Comparison(kind, lhs_push, rhs_push); |
| } |
| |
| |
| StaticCallInstr* IRRegExpMacroAssembler::StaticCall( |
| const Function& function) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(0); |
| return StaticCall(function, arguments); |
| } |
| |
| |
| StaticCallInstr* IRRegExpMacroAssembler::StaticCall( |
| const Function& function, |
| PushArgumentInstr* arg1) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(1); |
| arguments->Add(arg1); |
| |
| return StaticCall(function, arguments); |
| } |
| |
| |
| StaticCallInstr* IRRegExpMacroAssembler::StaticCall( |
| const Function& function, |
| PushArgumentInstr* arg1, |
| PushArgumentInstr* arg2) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(2); |
| arguments->Add(arg1); |
| arguments->Add(arg2); |
| |
| return StaticCall(function, arguments); |
| } |
| |
| |
| StaticCallInstr* IRRegExpMacroAssembler::StaticCall( |
| const Function& function, |
| ZoneGrowableArray<PushArgumentInstr*>* arguments) const { |
| return new(Z) StaticCallInstr(kNoSourcePos, |
| function, |
| Object::null_array(), |
| arguments, |
| ic_data_array_); |
| } |
| |
| |
| InstanceCallInstr* IRRegExpMacroAssembler::InstanceCall( |
| const InstanceCallDescriptor& desc, |
| PushArgumentInstr* arg1) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(1); |
| arguments->Add(arg1); |
| |
| return InstanceCall(desc, arguments); |
| } |
| |
| |
| InstanceCallInstr* IRRegExpMacroAssembler::InstanceCall( |
| const InstanceCallDescriptor& desc, |
| PushArgumentInstr* arg1, |
| PushArgumentInstr* arg2) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(2); |
| arguments->Add(arg1); |
| arguments->Add(arg2); |
| |
| return InstanceCall(desc, arguments); |
| } |
| |
| |
| InstanceCallInstr* IRRegExpMacroAssembler::InstanceCall( |
| const InstanceCallDescriptor& desc, |
| PushArgumentInstr* arg1, |
| PushArgumentInstr* arg2, |
| PushArgumentInstr* arg3) const { |
| ZoneGrowableArray<PushArgumentInstr*>* arguments = |
| new(Z) ZoneGrowableArray<PushArgumentInstr*>(3); |
| arguments->Add(arg1); |
| arguments->Add(arg2); |
| arguments->Add(arg3); |
| |
| return InstanceCall(desc, arguments); |
| } |
| |
| |
| InstanceCallInstr* IRRegExpMacroAssembler::InstanceCall( |
| const InstanceCallDescriptor& desc, |
| ZoneGrowableArray<PushArgumentInstr*> *arguments) const { |
| return |
| new(Z) InstanceCallInstr(kNoSourcePos, |
| desc.name, |
| desc.token_kind, |
| arguments, |
| Object::null_array(), |
| desc.checked_argument_count, |
| ic_data_array_); |
| } |
| |
| |
| LoadLocalInstr* IRRegExpMacroAssembler::LoadLocal(LocalVariable* local) const { |
| return new(Z) LoadLocalInstr(*local); |
| } |
| |
| |
| void IRRegExpMacroAssembler::StoreLocal(LocalVariable* local, |
| Value* value) { |
| Do(new(Z) StoreLocalInstr(*local, value)); |
| } |
| |
| |
| void IRRegExpMacroAssembler::set_current_instruction(Instruction* instruction) { |
| current_instruction_ = instruction; |
| } |
| |
| |
| Value* IRRegExpMacroAssembler::Bind(Definition* definition) { |
| AppendInstruction(definition); |
| definition->set_temp_index(temp_id_.Alloc()); |
| |
| return new(Z) Value(definition); |
| } |
| |
| |
| void IRRegExpMacroAssembler::Do(Definition* definition) { |
| AppendInstruction(definition); |
| } |
| |
| |
| Value* IRRegExpMacroAssembler::BindLoadLocal(const LocalVariable& local) { |
| if (local.IsConst()) { |
| return Bind(new(Z) ConstantInstr(*local.ConstValue())); |
| } |
| ASSERT(!local.is_captured()); |
| return Bind(new(Z) LoadLocalInstr(local)); |
| } |
| |
| |
| // In some cases, the V8 irregexp engine generates unreachable code by emitting |
| // a jmp not followed by a bind. We cannot do the same, since it is impossible |
| // to append to a block following a jmp. In such cases, assume that we are doing |
| // the correct thing, but output a warning when tracing. |
| #define HANDLE_DEAD_CODE_EMISSION() \ |
| if (current_instruction_ == NULL) { \ |
| if (FLAG_trace_irregexp) { \ |
| OS::Print("WARNING: Attempting to append to a closed assembler. " \ |
| "This could be either a bug or generation of dead code " \ |
| "inherited from V8.\n"); \ |
| } \ |
| BlockLabel dummy; \ |
| BindBlock(&dummy); \ |
| } |
| |
| void IRRegExpMacroAssembler::AppendInstruction(Instruction* instruction) { |
| HANDLE_DEAD_CODE_EMISSION(); |
| |
| ASSERT(current_instruction_ != NULL); |
| ASSERT(current_instruction_->next() == NULL); |
| |
| temp_id_.Dealloc(instruction->InputCount()); |
| arg_id_.Dealloc(instruction->ArgumentCount()); |
| |
| current_instruction_->LinkTo(instruction); |
| set_current_instruction(instruction); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CloseBlockWith(Instruction* instruction) { |
| HANDLE_DEAD_CODE_EMISSION(); |
| |
| ASSERT(current_instruction_ != NULL); |
| ASSERT(current_instruction_->next() == NULL); |
| |
| temp_id_.Dealloc(instruction->InputCount()); |
| arg_id_.Dealloc(instruction->ArgumentCount()); |
| |
| current_instruction_->LinkTo(instruction); |
| set_current_instruction(NULL); |
| } |
| |
| |
| void IRRegExpMacroAssembler::GoTo(BlockLabel* to) { |
| if (to == NULL) { |
| Backtrack(); |
| } else { |
| to->SetLinked(); |
| GoTo(to->block()); |
| } |
| } |
| |
| |
| // Closes the current block with a goto, and unsets current_instruction_. |
| // BindBlock() must be called before emission can continue. |
| void IRRegExpMacroAssembler::GoTo(JoinEntryInstr* to) { |
| HANDLE_DEAD_CODE_EMISSION(); |
| |
| ASSERT(current_instruction_ != NULL); |
| ASSERT(current_instruction_->next() == NULL); |
| current_instruction_->Goto(to); |
| set_current_instruction(NULL); |
| } |
| |
| |
| PushArgumentInstr* IRRegExpMacroAssembler::PushArgument(Value* value) { |
| arg_id_.Alloc(); |
| PushArgumentInstr* push = new(Z) PushArgumentInstr(value); |
| // Do *not* use Do() for push argument instructions. |
| AppendInstruction(push); |
| return push; |
| } |
| |
| |
| PushArgumentInstr* IRRegExpMacroAssembler::PushLocal(LocalVariable* local) { |
| return PushArgument(Bind(LoadLocal(local))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::Print(const char* str) { |
| Print(PushArgument( |
| Bind(new(Z) ConstantInstr( |
| String::ZoneHandle(Z, String::New(str, Heap::kOld)))))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::Print(PushArgumentInstr* argument) { |
| const Library& lib = Library::Handle(Library::CoreLibrary()); |
| const Function& print_fn = Function::ZoneHandle( |
| Z, lib.LookupFunctionAllowPrivate(Symbols::print())); |
| Do(StaticCall(print_fn, argument)); |
| } |
| |
| |
| void IRRegExpMacroAssembler::PrintBlocks() { |
| for (intptr_t i = 0; i < blocks_.length(); i++) { |
| FlowGraphPrinter::PrintBlock(blocks_[i], false); |
| } |
| } |
| |
| |
| intptr_t IRRegExpMacroAssembler::stack_limit_slack() { |
| return 32; |
| } |
| |
| |
| void IRRegExpMacroAssembler::AdvanceCurrentPosition(intptr_t by) { |
| TAG(); |
| if (by != 0) { |
| PushArgumentInstr* cur_pos_push = PushLocal(current_position_); |
| PushArgumentInstr* by_push = PushArgument(Bind(Int64Constant(by))); |
| |
| Value* new_pos_value = Bind(Add(cur_pos_push, by_push)); |
| StoreLocal(current_position_, new_pos_value); |
| } |
| } |
| |
| |
| void IRRegExpMacroAssembler::AdvanceRegister(intptr_t reg, intptr_t by) { |
| TAG(); |
| ASSERT(reg >= 0); |
| ASSERT(reg < registers_count_); |
| |
| if (by != 0) { |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(reg); |
| PushArgumentInstr* reg_push = PushArgument(LoadRegister(reg)); |
| PushArgumentInstr* by_push = PushArgument(Bind(Int64Constant(by))); |
| PushArgumentInstr* value_push = PushArgument(Bind(Add(reg_push, by_push))); |
| StoreRegister(registers_push, index_push, value_push); |
| } |
| } |
| |
| |
| void IRRegExpMacroAssembler::Backtrack() { |
| TAG(); |
| GoTo(backtrack_block_); |
| } |
| |
| |
| // A BindBlock is analogous to assigning a label to a basic block. |
| // If the BlockLabel does not yet contain a block, it is created. |
| // If there is a current instruction, append a goto to the bound block. |
| void IRRegExpMacroAssembler::BindBlock(BlockLabel* label) { |
| ASSERT(!label->IsBound()); |
| ASSERT(label->block()->next() == NULL); |
| |
| label->SetBound(block_id_.Alloc()); |
| blocks_.Add(label->block()); |
| |
| if (current_instruction_ != NULL) { |
| GoTo(label); |
| } |
| set_current_instruction(label->block()); |
| |
| // Print the id of the current block if tracing. |
| PRINT(PushArgument(Bind(Uint64Constant(label->block()->block_id())))); |
| } |
| |
| |
| intptr_t IRRegExpMacroAssembler::GetNextLocalIndex() { |
| intptr_t id = local_id_.Alloc(); |
| return kFirstLocalSlotFromFp - id; |
| } |
| |
| |
| Value* IRRegExpMacroAssembler::LoadRegister(intptr_t index) { |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(index); |
| return Bind(InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| registers_push, |
| index_push)); |
| } |
| |
| void IRRegExpMacroAssembler::StoreRegister(intptr_t index, intptr_t value) { |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(index); |
| PushArgumentInstr* value_push = PushArgument(Bind(Uint64Constant(value))); |
| StoreRegister(registers_push, index_push, value_push); |
| } |
| |
| |
| void IRRegExpMacroAssembler::StoreRegister(PushArgumentInstr* registers, |
| PushArgumentInstr* index, |
| PushArgumentInstr* value) { |
| TAG(); |
| Do(InstanceCall(InstanceCallDescriptor::FromToken(Token::kASSIGN_INDEX), |
| registers, |
| index, |
| value)); |
| } |
| |
| PushArgumentInstr* IRRegExpMacroAssembler::PushRegisterIndex(intptr_t index) { |
| if (registers_count_ <= index) { |
| registers_count_ = index + 1; |
| } |
| return PushArgument(Bind(Uint64Constant(index))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacter(uint32_t c, BlockLabel* on_equal) { |
| TAG(); |
| Definition* cur_char_def = LoadLocal(current_character_); |
| Definition* char_def = Uint64Constant(c); |
| |
| BranchOrBacktrack(Comparison(kEQ, cur_char_def, char_def), on_equal); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacterGT(uint16_t limit, |
| BlockLabel* on_greater) { |
| TAG(); |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(current_character_), |
| Uint64Constant(limit)), |
| on_greater); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckAtStart(BlockLabel* on_at_start) { |
| TAG(); |
| |
| BlockLabel not_at_start; |
| |
| // Did we start the match at the start of the string at all? |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(start_index_param_), |
| Uint64Constant(0)), |
| ¬_at_start); |
| |
| // If we did, are we still at the start of the input, i.e. is |
| // (offset == string_length * -1)? |
| Definition* neg_len_def = |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kNEGATE), |
| PushLocal(string_param_length_)); |
| Definition* offset_def = LoadLocal(current_position_); |
| BranchOrBacktrack(Comparison(kEQ, neg_len_def, offset_def), |
| on_at_start); |
| |
| BindBlock(¬_at_start); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotAtStart(BlockLabel* on_not_at_start) { |
| TAG(); |
| |
| // Did we start the match at the start of the string at all? |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(start_index_param_), |
| Uint64Constant(0)), |
| on_not_at_start); |
| |
| // If we did, are we still at the start of the input, i.e. is |
| // (offset == string_length * -1)? |
| Definition* neg_len_def = |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kNEGATE), |
| PushLocal(string_param_length_)); |
| Definition* offset_def = LoadLocal(current_position_); |
| BranchOrBacktrack(Comparison(kNE, neg_len_def, offset_def), |
| on_not_at_start); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacterLT(uint16_t limit, |
| BlockLabel* on_less) { |
| TAG(); |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(current_character_), |
| Uint64Constant(limit)), |
| on_less); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckGreedyLoop(BlockLabel* on_equal) { |
| TAG(); |
| |
| BlockLabel fallthrough; |
| |
| Definition* head = PeekStack(); |
| Definition* cur_pos_def = LoadLocal(current_position_); |
| BranchOrBacktrack(Comparison(kNE, head, cur_pos_def), |
| &fallthrough); |
| |
| // Pop, throwing away the value. |
| Do(PopStack()); |
| |
| BranchOrBacktrack(NULL, on_equal); |
| |
| BindBlock(&fallthrough); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotBackReferenceIgnoreCase( |
| intptr_t start_reg, |
| BlockLabel* on_no_match) { |
| TAG(); |
| ASSERT(start_reg + 1 <= registers_count_); |
| |
| BlockLabel fallthrough; |
| |
| PushArgumentInstr* end_push = PushArgument(LoadRegister(start_reg + 1)); |
| PushArgumentInstr* start_push = PushArgument(LoadRegister(start_reg)); |
| StoreLocal(capture_length_, Bind(Sub(end_push, start_push))); |
| |
| // The length of a capture should not be negative. This can only happen |
| // if the end of the capture is unrecorded, or at a point earlier than |
| // the start of the capture. |
| // BranchOrBacktrack(less, on_no_match); |
| |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(capture_length_), |
| Uint64Constant(0)), |
| on_no_match); |
| |
| // If length is zero, either the capture is empty or it is completely |
| // uncaptured. In either case succeed immediately. |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(capture_length_), |
| Uint64Constant(0)), |
| &fallthrough); |
| |
| |
| // Check that there are sufficient characters left in the input. |
| PushArgumentInstr* pos_push = PushLocal(current_position_); |
| PushArgumentInstr* len_push = PushLocal(capture_length_); |
| BranchOrBacktrack( |
| Comparison(kGT, |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kADD), |
| pos_push, |
| len_push), |
| Uint64Constant(0)), |
| on_no_match); |
| |
| pos_push = PushLocal(current_position_); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(match_start_index_, Bind(Add(pos_push, len_push))); |
| |
| pos_push = PushArgument(LoadRegister(start_reg)); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(capture_start_index_, Bind(Add(pos_push, len_push))); |
| |
| pos_push = PushLocal(match_start_index_); |
| len_push = PushLocal(capture_length_); |
| StoreLocal(match_end_index_, Bind(Add(pos_push, len_push))); |
| |
| BlockLabel success; |
| if (mode_ == ASCII) { |
| BlockLabel loop_increment; |
| BlockLabel loop; |
| BindBlock(&loop); |
| |
| StoreLocal(char_in_capture_, CharacterAt(capture_start_index_)); |
| StoreLocal(char_in_match_, CharacterAt(match_start_index_)); |
| |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(char_in_capture_), |
| LoadLocal(char_in_match_)), |
| &loop_increment); |
| |
| // Mismatch, try case-insensitive match (converting letters to lower-case). |
| PushArgumentInstr* match_char_push = PushLocal(char_in_match_); |
| PushArgumentInstr* mask_push = PushArgument(Bind(Uint64Constant(0x20))); |
| StoreLocal(char_in_match_, |
| Bind(InstanceCall( |
| InstanceCallDescriptor::FromToken(Token::kBIT_OR), |
| match_char_push, |
| mask_push))); |
| |
| BlockLabel convert_capture; |
| BlockLabel on_not_in_range; |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(char_in_match_), |
| Uint64Constant('a')), |
| &on_not_in_range); |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(char_in_match_), |
| Uint64Constant('z')), |
| &on_not_in_range); |
| GoTo(&convert_capture); |
| BindBlock(&on_not_in_range); |
| |
| // Latin-1: Check for values in range [224,254] but not 247. |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(char_in_match_), |
| Uint64Constant(224)), |
| on_no_match); |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(char_in_match_), |
| Uint64Constant(254)), |
| on_no_match); |
| |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(char_in_match_), |
| Uint64Constant(247)), |
| on_no_match); |
| |
| // Also convert capture character. |
| BindBlock(&convert_capture); |
| |
| PushArgumentInstr* capture_char_push = PushLocal(char_in_capture_); |
| mask_push = PushArgument(Bind(Uint64Constant(0x20))); |
| StoreLocal(char_in_capture_, |
| Bind(InstanceCall( |
| InstanceCallDescriptor::FromToken(Token::kBIT_OR), |
| capture_char_push, |
| mask_push))); |
| |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(char_in_match_), |
| LoadLocal(char_in_capture_)), |
| on_no_match); |
| |
| BindBlock(&loop_increment); |
| |
| // Increment indexes into capture and match strings. |
| PushArgumentInstr* index_push = PushLocal(capture_start_index_); |
| PushArgumentInstr* inc_push = PushArgument(Bind(Uint64Constant(1))); |
| StoreLocal(capture_start_index_, Bind(Add(index_push, inc_push))); |
| |
| index_push = PushLocal(match_start_index_); |
| inc_push = PushArgument(Bind(Uint64Constant(1))); |
| StoreLocal(match_start_index_, Bind(Add(index_push, inc_push))); |
| |
| // Compare to end of match, and loop if not done. |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(match_start_index_), |
| LoadLocal(match_end_index_)), |
| &loop); |
| } else { |
| ASSERT(mode_ == UC16); |
| |
| Value* string_value = Bind(LoadLocal(string_param_)); |
| Value* lhs_index_value = Bind(LoadLocal(match_start_index_)); |
| Value* rhs_index_value = Bind(LoadLocal(capture_start_index_)); |
| Value* length_value = Bind(LoadLocal(capture_length_)); |
| |
| Definition* is_match_def = |
| new(Z) CaseInsensitiveCompareUC16Instr( |
| string_value, |
| lhs_index_value, |
| rhs_index_value, |
| length_value, |
| specialization_cid_); |
| |
| BranchOrBacktrack(Comparison(kNE, is_match_def, BoolConstant(true)), |
| on_no_match); |
| } |
| |
| BindBlock(&success); |
| |
| // Move current character position to position after match. |
| PushArgumentInstr* match_end_push = PushLocal(match_end_index_); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(current_position_, Bind(Sub(match_end_push, len_push))); |
| |
| BindBlock(&fallthrough); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotBackReference( |
| intptr_t start_reg, |
| BlockLabel* on_no_match) { |
| TAG(); |
| ASSERT(start_reg + 1 <= registers_count_); |
| |
| BlockLabel fallthrough; |
| BlockLabel success; |
| |
| // Find length of back-referenced capture. |
| PushArgumentInstr* end_push = PushArgument(LoadRegister(start_reg + 1)); |
| PushArgumentInstr* start_push = PushArgument(LoadRegister(start_reg)); |
| StoreLocal(capture_length_, Bind(Sub(end_push, start_push))); |
| |
| // Fail on partial or illegal capture (start of capture after end of capture). |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(capture_length_), |
| Uint64Constant(0)), |
| on_no_match); |
| |
| // Succeed on empty capture (including no capture) |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(capture_length_), |
| Uint64Constant(0)), |
| &fallthrough); |
| |
| // Check that there are sufficient characters left in the input. |
| PushArgumentInstr* pos_push = PushLocal(current_position_); |
| PushArgumentInstr* len_push = PushLocal(capture_length_); |
| BranchOrBacktrack( |
| Comparison(kGT, |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kADD), |
| pos_push, |
| len_push), |
| Uint64Constant(0)), |
| on_no_match); |
| |
| // Compute pointers to match string and capture string. |
| pos_push = PushLocal(current_position_); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(match_start_index_, Bind(Add(pos_push, len_push))); |
| |
| pos_push = PushArgument(LoadRegister(start_reg)); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(capture_start_index_, Bind(Add(pos_push, len_push))); |
| |
| pos_push = PushLocal(match_start_index_); |
| len_push = PushLocal(capture_length_); |
| StoreLocal(match_end_index_, Bind(Add(pos_push, len_push))); |
| |
| BlockLabel loop; |
| BindBlock(&loop); |
| |
| StoreLocal(char_in_capture_, CharacterAt(capture_start_index_)); |
| StoreLocal(char_in_match_, CharacterAt(match_start_index_)); |
| |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(char_in_capture_), |
| LoadLocal(char_in_match_)), |
| on_no_match); |
| |
| // Increment indexes into capture and match strings. |
| PushArgumentInstr* index_push = PushLocal(capture_start_index_); |
| PushArgumentInstr* inc_push = PushArgument(Bind(Uint64Constant(1))); |
| StoreLocal(capture_start_index_, Bind(Add(index_push, inc_push))); |
| |
| index_push = PushLocal(match_start_index_); |
| inc_push = PushArgument(Bind(Uint64Constant(1))); |
| StoreLocal(match_start_index_, Bind(Add(index_push, inc_push))); |
| |
| // Check if we have reached end of match area. |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(match_start_index_), |
| LoadLocal(match_end_index_)), |
| &loop); |
| |
| BindBlock(&success); |
| |
| // Move current character position to position after match. |
| PushArgumentInstr* match_end_push = PushLocal(match_end_index_); |
| len_push = PushLocal(string_param_length_); |
| StoreLocal(current_position_, Bind(Sub(match_end_push, len_push))); |
| |
| BindBlock(&fallthrough); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotCharacter(uint32_t c, |
| BlockLabel* on_not_equal) { |
| TAG(); |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(current_character_), |
| Uint64Constant(c)), |
| on_not_equal); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacterAfterAnd(uint32_t c, |
| uint32_t mask, |
| BlockLabel* on_equal) { |
| TAG(); |
| |
| Definition* actual_def = LoadLocal(current_character_); |
| Definition* expected_def = Uint64Constant(c); |
| |
| PushArgumentInstr* actual_push = PushArgument(Bind(actual_def)); |
| PushArgumentInstr* mask_push = PushArgument(Bind(Uint64Constant(mask))); |
| actual_def = InstanceCall(InstanceCallDescriptor::FromToken(Token::kBIT_AND), |
| actual_push, |
| mask_push); |
| |
| BranchOrBacktrack(Comparison(kEQ, actual_def, expected_def), on_equal); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotCharacterAfterAnd( |
| uint32_t c, |
| uint32_t mask, |
| BlockLabel* on_not_equal) { |
| TAG(); |
| |
| Definition* actual_def = LoadLocal(current_character_); |
| Definition* expected_def = Uint64Constant(c); |
| |
| PushArgumentInstr* actual_push = PushArgument(Bind(actual_def)); |
| PushArgumentInstr* mask_push = PushArgument(Bind(Uint64Constant(mask))); |
| actual_def = InstanceCall(InstanceCallDescriptor::FromToken(Token::kBIT_AND), |
| actual_push, |
| mask_push); |
| |
| BranchOrBacktrack(Comparison(kNE, actual_def, expected_def), on_not_equal); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckNotCharacterAfterMinusAnd( |
| uint16_t c, |
| uint16_t minus, |
| uint16_t mask, |
| BlockLabel* on_not_equal) { |
| TAG(); |
| ASSERT(minus < Utf16::kMaxCodeUnit); // NOLINT |
| |
| Definition* actual_def = LoadLocal(current_character_); |
| Definition* expected_def = Uint64Constant(c); |
| |
| PushArgumentInstr* actual_push = PushArgument(Bind(actual_def)); |
| PushArgumentInstr* minus_push = PushArgument(Bind(Uint64Constant(minus))); |
| |
| actual_push = PushArgument(Bind(Sub(actual_push, minus_push))); |
| PushArgumentInstr* mask_push = PushArgument(Bind(Uint64Constant(mask))); |
| actual_def = InstanceCall(InstanceCallDescriptor::FromToken(Token::kBIT_AND), |
| actual_push, |
| mask_push); |
| |
| BranchOrBacktrack(Comparison(kNE, actual_def, expected_def), on_not_equal); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacterInRange( |
| uint16_t from, |
| uint16_t to, |
| BlockLabel* on_in_range) { |
| TAG(); |
| ASSERT(from <= to); |
| |
| // TODO(zerny): All range comparisons could be done cheaper with unsigned |
| // compares. This pattern repeats in various places. |
| |
| BlockLabel on_not_in_range; |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(current_character_), |
| Uint64Constant(from)), |
| &on_not_in_range); |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(current_character_), |
| Uint64Constant(to)), |
| &on_not_in_range); |
| BranchOrBacktrack(NULL, on_in_range); |
| |
| BindBlock(&on_not_in_range); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckCharacterNotInRange( |
| uint16_t from, |
| uint16_t to, |
| BlockLabel* on_not_in_range) { |
| TAG(); |
| ASSERT(from <= to); |
| |
| BranchOrBacktrack(Comparison(kLT, |
| LoadLocal(current_character_), |
| Uint64Constant(from)), |
| on_not_in_range); |
| |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(current_character_), |
| Uint64Constant(to)), |
| on_not_in_range); |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckBitInTable( |
| const TypedData& table, |
| BlockLabel* on_bit_set) { |
| TAG(); |
| |
| PushArgumentInstr* table_push = |
| PushArgument(Bind(new(Z) ConstantInstr(table))); |
| PushArgumentInstr* index_push = PushLocal(current_character_); |
| |
| if (mode_ != ASCII || kTableMask != Symbols::kMaxOneCharCodeSymbol) { |
| PushArgumentInstr* mask_push = |
| PushArgument(Bind(Uint64Constant(kTableSize - 1))); |
| index_push = PushArgument( |
| Bind(InstanceCall(InstanceCallDescriptor::FromToken(Token::kBIT_AND), |
| index_push, |
| mask_push))); |
| } |
| |
| Definition* byte_def = |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| table_push, |
| index_push); |
| Definition* zero_def = Int64Constant(0); |
| |
| BranchOrBacktrack(Comparison(kNE, byte_def, zero_def), on_bit_set); |
| } |
| |
| |
| bool IRRegExpMacroAssembler::CheckSpecialCharacterClass( |
| uint16_t type, |
| BlockLabel* on_no_match) { |
| TAG(); |
| |
| // 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. |
| BlockLabel success; |
| // Space (' '). |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant(' ')), |
| &success); |
| // Check range 0x09..0x0d. |
| CheckCharacterInRange('\t', '\r', &success); |
| // \u00a0 (NBSP). |
| BranchOrBacktrack(Comparison(kNE, |
| LoadLocal(current_character_), |
| Uint64Constant(0x00a0)), |
| on_no_match); |
| BindBlock(&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') |
| CheckCharacterNotInRange('0', '9', on_no_match); |
| return true; |
| case 'D': |
| // Match non ASCII-digits |
| CheckCharacterInRange('0', '9', on_no_match); |
| return true; |
| case '.': { |
| // Match non-newlines (not 0x0a('\n'), 0x0d('\r'), 0x2028 and 0x2029) |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant('\n')), |
| on_no_match); |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant('\r')), |
| on_no_match); |
| if (mode_ == UC16) { |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant(0x2028)), |
| on_no_match); |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant(0x2029)), |
| on_no_match); |
| } |
| return true; |
| } |
| case 'w': { |
| if (mode_ != ASCII) { |
| // Table is 128 entries, so all ASCII characters can be tested. |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(current_character_), |
| Uint64Constant('z')), |
| on_no_match); |
| } |
| |
| PushArgumentInstr* table_push = |
| PushArgument(Bind(WordCharacterMapConstant())); |
| PushArgumentInstr* index_push = PushLocal(current_character_); |
| |
| Definition* byte_def = |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| table_push, |
| index_push); |
| Definition* zero_def = Int64Constant(0); |
| |
| BranchOrBacktrack(Comparison(kEQ, byte_def, zero_def), on_no_match); |
| |
| return true; |
| } |
| case 'W': { |
| BlockLabel done; |
| if (mode_ != ASCII) { |
| // Table is 128 entries, so all ASCII characters can be tested. |
| BranchOrBacktrack(Comparison(kGT, |
| LoadLocal(current_character_), |
| Uint64Constant('z')), |
| &done); |
| } |
| |
| // TODO(zerny): Refactor to use CheckBitInTable if possible. |
| |
| PushArgumentInstr* table_push = |
| PushArgument(Bind(WordCharacterMapConstant())); |
| PushArgumentInstr* index_push = PushLocal(current_character_); |
| |
| Definition* byte_def = |
| InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| table_push, |
| index_push); |
| Definition* zero_def = Int64Constant(0); |
| |
| BranchOrBacktrack(Comparison(kNE, byte_def, zero_def), on_no_match); |
| |
| if (mode_ != ASCII) { |
| BindBlock(&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 '.'. |
| BlockLabel success; |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant('\n')), |
| &success); |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant('\r')), |
| &success); |
| if (mode_ == UC16) { |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant(0x2028)), |
| &success); |
| BranchOrBacktrack(Comparison(kEQ, |
| LoadLocal(current_character_), |
| Uint64Constant(0x2029)), |
| &success); |
| } |
| BranchOrBacktrack(NULL, on_no_match); |
| BindBlock(&success); |
| return true; |
| } |
| // No custom implementation (yet): s(uint16_t), S(uint16_t). |
| default: |
| return false; |
| } |
| } |
| |
| |
| void IRRegExpMacroAssembler::Fail() { |
| TAG(); |
| ASSERT(FAILURE == 0); // Return value for failure is zero. |
| if (!global()) { |
| UNREACHABLE(); // Dart regexps are always global. |
| } |
| GoTo(exit_block_); |
| } |
| |
| |
| void IRRegExpMacroAssembler::IfRegisterGE(intptr_t reg, |
| intptr_t comparand, |
| BlockLabel* if_ge) { |
| TAG(); |
| PushArgumentInstr* reg_push = PushArgument(LoadRegister(reg)); |
| PushArgumentInstr* pos = PushArgument(Bind(Int64Constant(comparand))); |
| BranchOrBacktrack(Comparison(kGTE, reg_push, pos), if_ge); |
| } |
| |
| |
| void IRRegExpMacroAssembler::IfRegisterLT(intptr_t reg, |
| intptr_t comparand, |
| BlockLabel* if_lt) { |
| TAG(); |
| PushArgumentInstr* reg_push = PushArgument(LoadRegister(reg)); |
| PushArgumentInstr* pos = PushArgument(Bind(Int64Constant(comparand))); |
| BranchOrBacktrack(Comparison(kLT, reg_push, pos), if_lt); |
| } |
| |
| |
| void IRRegExpMacroAssembler::IfRegisterEqPos(intptr_t reg, |
| BlockLabel* if_eq) { |
| TAG(); |
| PushArgumentInstr* reg_push = PushArgument(LoadRegister(reg)); |
| PushArgumentInstr* pos = PushArgument(Bind(LoadLocal(current_position_))); |
| BranchOrBacktrack(Comparison(kEQ, reg_push, pos), if_eq); |
| } |
| |
| |
| RegExpMacroAssembler::IrregexpImplementation |
| IRRegExpMacroAssembler::Implementation() { |
| return kIRImplementation; |
| } |
| |
| |
| void IRRegExpMacroAssembler::LoadCurrentCharacter(intptr_t cp_offset, |
| BlockLabel* on_end_of_input, |
| bool check_bounds, |
| intptr_t characters) { |
| TAG(); |
| 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 IRRegExpMacroAssembler::PopCurrentPosition() { |
| TAG(); |
| StoreLocal(current_position_, Bind(PopStack())); |
| } |
| |
| |
| void IRRegExpMacroAssembler::PopRegister(intptr_t reg) { |
| TAG(); |
| ASSERT(reg < registers_count_); |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(reg); |
| PushArgumentInstr* pop_push = PushArgument(Bind(PopStack())); |
| StoreRegister(registers_push, index_push, pop_push); |
| } |
| |
| |
| void IRRegExpMacroAssembler::PushStack(Definition *definition) { |
| PushArgumentInstr* stack_push = PushLocal(stack_); |
| PushArgumentInstr* stack_pointer_push = PushLocal(stack_pointer_); |
| StoreLocal(stack_pointer_, |
| Bind(Add(stack_pointer_push, |
| PushArgument(Bind(Uint64Constant(1)))))); |
| stack_pointer_push = PushLocal(stack_pointer_); |
| // TODO(zerny): bind value and push could break stack discipline. |
| PushArgumentInstr* value_push = PushArgument(Bind(definition)); |
| Do(InstanceCall(InstanceCallDescriptor::FromToken(Token::kASSIGN_INDEX), |
| stack_push, |
| stack_pointer_push, |
| value_push)); |
| } |
| |
| |
| Definition* IRRegExpMacroAssembler::PopStack() { |
| PushArgumentInstr* stack_push = PushLocal(stack_); |
| PushArgumentInstr* stack_pointer_push1 = PushLocal(stack_pointer_); |
| PushArgumentInstr* stack_pointer_push2 = PushLocal(stack_pointer_); |
| StoreLocal(stack_pointer_, |
| Bind(Sub(stack_pointer_push2, |
| PushArgument(Bind(Uint64Constant(1)))))); |
| return InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| stack_push, |
| stack_pointer_push1); |
| } |
| |
| |
| Definition* IRRegExpMacroAssembler::PeekStack() { |
| PushArgumentInstr* stack_push = PushLocal(stack_); |
| PushArgumentInstr* stack_pointer_push = PushLocal(stack_pointer_); |
| return InstanceCall(InstanceCallDescriptor::FromToken(Token::kINDEX), |
| stack_push, |
| stack_pointer_push); |
| } |
| |
| |
| // Pushes the location corresponding to label to the backtracking stack. |
| void IRRegExpMacroAssembler::PushBacktrack(BlockLabel* label) { |
| TAG(); |
| |
| // Ensure that targets of indirect jumps are never accessed through a |
| // normal control flow instructions by creating a new block for each backtrack |
| // target. |
| IndirectEntryInstr* indirect_target = IndirectWithJoinGoto(label->block()); |
| |
| // Add a fake edge from the graph entry for data flow analysis. |
| entry_block_->AddIndirectEntry(indirect_target); |
| |
| ConstantInstr* offset = Uint64Constant(indirect_target->indirect_id()); |
| PushStack(offset); |
| CheckStackLimit(); |
| } |
| |
| |
| void IRRegExpMacroAssembler::PushCurrentPosition() { |
| TAG(); |
| PushStack(LoadLocal(current_position_)); |
| } |
| |
| |
| void IRRegExpMacroAssembler::PushRegister(intptr_t reg) { |
| TAG(); |
| // TODO(zerny): Refactor PushStack so it can be reused here. |
| PushArgumentInstr* stack_push = PushLocal(stack_); |
| PushArgumentInstr* stack_pointer_push = PushLocal(stack_pointer_); |
| StoreLocal(stack_pointer_, |
| Bind(Add(stack_pointer_push, |
| PushArgument(Bind(Uint64Constant(1)))))); |
| stack_pointer_push = PushLocal(stack_pointer_); |
| // TODO(zerny): bind value and push could break stack discipline. |
| PushArgumentInstr* value_push = PushArgument(LoadRegister(reg)); |
| Do(InstanceCall(InstanceCallDescriptor::FromToken(Token::kASSIGN_INDEX), |
| stack_push, |
| stack_pointer_push, |
| value_push)); |
| CheckStackLimit(); |
| } |
| |
| |
| // Checks that (stack.capacity - stack_limit_slack) > stack_pointer. |
| // This ensures that up to stack_limit_slack stack pushes can be |
| // done without exhausting the stack space. If the check fails the |
| // stack will be grown. |
| void IRRegExpMacroAssembler::CheckStackLimit() { |
| TAG(); |
| PushArgumentInstr* stack_push = PushLocal(stack_); |
| PushArgumentInstr* length_push = PushArgument(Bind(InstanceCall( |
| InstanceCallDescriptor( |
| String::ZoneHandle(Field::GetterSymbol(Symbols::Length()))), |
| stack_push))); |
| PushArgumentInstr* capacity_push = PushArgument(Bind(Sub( |
| length_push, |
| PushArgument(Bind(Uint64Constant(stack_limit_slack())))))); |
| PushArgumentInstr* stack_pointer_push = PushLocal(stack_pointer_); |
| BranchInstr* branch = new(Z) BranchInstr( |
| Comparison(kGT, capacity_push, stack_pointer_push)); |
| CloseBlockWith(branch); |
| |
| BlockLabel grow_stack; |
| BlockLabel fallthrough; |
| *branch->true_successor_address() = |
| TargetWithJoinGoto(fallthrough.block()); |
| *branch->false_successor_address() = |
| TargetWithJoinGoto(grow_stack.block()); |
| |
| BindBlock(&grow_stack); |
| GrowStack(); |
| |
| BindBlock(&fallthrough); |
| } |
| |
| |
| void IRRegExpMacroAssembler::GrowStack() { |
| TAG(); |
| Value* cell = Bind(new(Z) ConstantInstr(stack_array_cell_)); |
| StoreLocal(stack_, Bind(new(Z) GrowRegExpStackInstr(cell))); |
| } |
| |
| |
| void IRRegExpMacroAssembler::ReadCurrentPositionFromRegister(intptr_t reg) { |
| TAG(); |
| StoreLocal(current_position_, LoadRegister(reg)); |
| } |
| |
| // Resets the tip of the stack to the value stored in reg. |
| void IRRegExpMacroAssembler::ReadStackPointerFromRegister(intptr_t reg) { |
| TAG(); |
| ASSERT(reg < registers_count_); |
| StoreLocal(stack_pointer_, LoadRegister(reg)); |
| } |
| |
| void IRRegExpMacroAssembler::SetCurrentPositionFromEnd(intptr_t by) { |
| TAG(); |
| |
| BlockLabel after_position; |
| |
| Definition* cur_pos_def = LoadLocal(current_position_); |
| Definition* by_value_def = Int64Constant(-by); |
| |
| BranchOrBacktrack(Comparison(kGTE, cur_pos_def, by_value_def), |
| &after_position); |
| |
| StoreLocal(current_position_, Bind(Int64Constant(-by))); |
| |
| // 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); |
| |
| BindBlock(&after_position); |
| } |
| |
| |
| void IRRegExpMacroAssembler::SetRegister(intptr_t reg, intptr_t to) { |
| TAG(); |
| // Reserved for positions! |
| ASSERT(reg >= saved_registers_count_); |
| StoreRegister(reg, to); |
| } |
| |
| |
| bool IRRegExpMacroAssembler::Succeed() { |
| TAG(); |
| GoTo(success_block_); |
| return global(); |
| } |
| |
| |
| void IRRegExpMacroAssembler::WriteCurrentPositionToRegister( |
| intptr_t reg, intptr_t cp_offset) { |
| TAG(); |
| |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(reg); |
| PushArgumentInstr* pos_push = PushLocal(current_position_); |
| PushArgumentInstr* off_push = PushArgument(Bind(Int64Constant(cp_offset))); |
| PushArgumentInstr* neg_off_push = PushArgument(Bind(Add(pos_push, off_push))); |
| // Push the negative offset; these are converted to positive string positions |
| // within the success block. |
| StoreRegister(registers_push, index_push, neg_off_push); |
| } |
| |
| |
| void IRRegExpMacroAssembler::ClearRegisters( |
| intptr_t reg_from, intptr_t reg_to) { |
| TAG(); |
| |
| ASSERT(reg_from <= reg_to); |
| |
| // In order to clear registers to a final result value of -1, set them to |
| // (-1 - string length), the offset of -1 from the end of the string. |
| |
| for (intptr_t reg = reg_from; reg <= reg_to; reg++) { |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(reg); |
| PushArgumentInstr* minus_one_push = |
| PushArgument(Bind(Int64Constant(-1))); |
| PushArgumentInstr* length_push = PushLocal(string_param_length_); |
| PushArgumentInstr* value_push = |
| PushArgument(Bind(Sub(minus_one_push, length_push))); |
| StoreRegister(registers_push, index_push, value_push); |
| } |
| } |
| |
| |
| void IRRegExpMacroAssembler::WriteStackPointerToRegister(intptr_t reg) { |
| TAG(); |
| |
| PushArgumentInstr* registers_push = PushLocal(registers_); |
| PushArgumentInstr* index_push = PushRegisterIndex(reg); |
| PushArgumentInstr* tip_push = PushLocal(stack_pointer_); |
| StoreRegister(registers_push, index_push, tip_push); |
| } |
| |
| |
| // Private methods: |
| |
| |
| void IRRegExpMacroAssembler::CheckPosition(intptr_t cp_offset, |
| BlockLabel* on_outside_input) { |
| TAG(); |
| Definition* curpos_def = LoadLocal(current_position_); |
| Definition* cp_off_def = Int64Constant(-cp_offset); |
| |
| // If (current_position_ < -cp_offset), we are in bounds. |
| // Remember, current_position_ is a negative offset from the string end. |
| |
| BranchOrBacktrack(Comparison(kGTE, curpos_def, cp_off_def), |
| on_outside_input); |
| } |
| |
| |
| void IRRegExpMacroAssembler::BranchOrBacktrack( |
| ComparisonInstr* comparison, |
| BlockLabel* true_successor) { |
| if (comparison == NULL) { // No condition |
| if (true_successor == NULL) { |
| Backtrack(); |
| return; |
| } |
| GoTo(true_successor); |
| return; |
| } |
| |
| // If no successor block has been passed in, backtrack. |
| JoinEntryInstr* true_successor_block = backtrack_block_; |
| if (true_successor != NULL) { |
| true_successor->SetLinked(); |
| true_successor_block = true_successor->block(); |
| } |
| ASSERT(true_successor_block != NULL); |
| |
| // If the condition is not true, fall through to a new block. |
| BlockLabel fallthrough; |
| |
| BranchInstr* branch = new(Z) BranchInstr(comparison); |
| *branch->true_successor_address() = |
| TargetWithJoinGoto(true_successor_block); |
| *branch->false_successor_address() = |
| TargetWithJoinGoto(fallthrough.block()); |
| |
| CloseBlockWith(branch); |
| BindBlock(&fallthrough); |
| } |
| |
| |
| TargetEntryInstr* IRRegExpMacroAssembler::TargetWithJoinGoto( |
| JoinEntryInstr* dst) { |
| TargetEntryInstr* target = new(Z) TargetEntryInstr( |
| block_id_.Alloc(), kInvalidTryIndex); |
| blocks_.Add(target); |
| |
| target->AppendInstruction(new(Z) GotoInstr(dst)); |
| |
| return target; |
| } |
| |
| |
| IndirectEntryInstr* IRRegExpMacroAssembler::IndirectWithJoinGoto( |
| JoinEntryInstr* dst) { |
| IndirectEntryInstr* target = new(Z) IndirectEntryInstr( |
| block_id_.Alloc(), indirect_id_.Alloc(), kInvalidTryIndex); |
| blocks_.Add(target); |
| |
| target->AppendInstruction(new(Z) GotoInstr(dst)); |
| |
| return target; |
| } |
| |
| |
| void IRRegExpMacroAssembler::CheckPreemption() { |
| TAG(); |
| AppendInstruction(new(Z) CheckStackOverflowInstr(kNoSourcePos, 0)); |
| } |
| |
| |
| Definition* IRRegExpMacroAssembler::Add( |
| PushArgumentInstr* lhs, |
| PushArgumentInstr* rhs) { |
| return InstanceCall(InstanceCallDescriptor::FromToken(Token::kADD), lhs, rhs); |
| } |
| |
| |
| Definition* IRRegExpMacroAssembler::Sub( |
| PushArgumentInstr* lhs, |
| PushArgumentInstr* rhs) { |
| return InstanceCall(InstanceCallDescriptor::FromToken(Token::kSUB), lhs, rhs); |
| } |
| |
| |
| void IRRegExpMacroAssembler::LoadCurrentCharacterUnchecked( |
| intptr_t cp_offset, intptr_t characters) { |
| TAG(); |
| |
| ASSERT(characters == 1 || CanReadUnaligned()); |
| if (mode_ == ASCII) { |
| ASSERT(characters == 1 || characters == 2 || characters == 4); |
| } else { |
| ASSERT(mode_ == UC16); |
| ASSERT(characters == 1 || characters == 2); |
| } |
| |
| // Calculate the addressed string index as: |
| // cp_offset + current_position_ + string_param_length_ |
| // TODO(zerny): Avoid generating 'add' instance-calls here. |
| PushArgumentInstr* off_arg = |
| PushArgument(Bind(Int64Constant(cp_offset))); |
| PushArgumentInstr* pos_arg = |
| PushArgument(BindLoadLocal(*current_position_)); |
| PushArgumentInstr* off_pos_arg = |
| PushArgument(Bind(Add(off_arg, pos_arg))); |
| PushArgumentInstr* len_arg = |
| PushArgument(BindLoadLocal(*string_param_length_)); |
| // Index is stored in a temporary local so that we can later load it safely. |
| StoreLocal(index_temp_, Bind(Add(off_pos_arg, len_arg))); |
| |
| // Load and store the code units. |
| Value* code_unit_value = LoadCodeUnitsAt(index_temp_, characters); |
| StoreLocal(current_character_, code_unit_value); |
| PRINT(PushLocal(current_character_)); |
| } |
| |
| |
| Value* IRRegExpMacroAssembler::CharacterAt(LocalVariable* index) { |
| return LoadCodeUnitsAt(index, 1); |
| } |
| |
| |
| Value* IRRegExpMacroAssembler::LoadCodeUnitsAt(LocalVariable* index, |
| intptr_t characters) { |
| // Bind the pattern as the load receiver. |
| Value* pattern_val = BindLoadLocal(*string_param_); |
| if (RawObject::IsExternalStringClassId(specialization_cid_)) { |
| // The data of an external string is stored through two indirections. |
| intptr_t external_offset = 0; |
| intptr_t data_offset = 0; |
| if (specialization_cid_ == kExternalOneByteStringCid) { |
| external_offset = ExternalOneByteString::external_data_offset(); |
| data_offset = RawExternalOneByteString::ExternalData::data_offset(); |
| } else if (specialization_cid_ == kExternalTwoByteStringCid) { |
| external_offset = ExternalTwoByteString::external_data_offset(); |
| data_offset = RawExternalTwoByteString::ExternalData::data_offset(); |
| } else { |
| UNREACHABLE(); |
| } |
| // This pushes untagged values on the stack which are immediately consumed: |
| // the first value is consumed to obtain the second value which is consumed |
| // by LoadCodeUnitsAtInstr below. |
| Value* external_val = |
| Bind(new(Z) LoadUntaggedInstr(pattern_val, external_offset)); |
| pattern_val = |
| Bind(new(Z) LoadUntaggedInstr(external_val, data_offset)); |
| } |
| |
| // Here pattern_val might be untagged so this must not trigger a GC. |
| Value* index_val = BindLoadLocal(*index); |
| |
| return Bind(new(Z) LoadCodeUnitsInstr( |
| pattern_val, |
| index_val, |
| characters, |
| specialization_cid_, |
| Scanner::kNoSourcePos)); |
| } |
| |
| |
| #undef __ |
| |
| } // namespace dart |