Index: src/jsregexp.cc |
diff --git a/src/jsregexp.cc b/src/jsregexp.cc |
deleted file mode 100644 |
index fc95c5e0b80f8de83f5f1805ce50cb42de0dd19b..0000000000000000000000000000000000000000 |
--- a/src/jsregexp.cc |
+++ /dev/null |
@@ -1,6412 +0,0 @@ |
-// Copyright 2012 the V8 project authors. All rights reserved. |
-// Use of this source code is governed by a BSD-style license that can be |
-// found in the LICENSE file. |
- |
-#include "src/v8.h" |
- |
-#include "src/ast.h" |
-#include "src/base/platform/platform.h" |
-#include "src/compilation-cache.h" |
-#include "src/compiler.h" |
-#include "src/execution.h" |
-#include "src/factory.h" |
-#include "src/jsregexp-inl.h" |
-#include "src/jsregexp.h" |
-#include "src/messages.h" |
-#include "src/ostreams.h" |
-#include "src/parser.h" |
-#include "src/regexp-macro-assembler.h" |
-#include "src/regexp-macro-assembler-irregexp.h" |
-#include "src/regexp-macro-assembler-tracer.h" |
-#include "src/regexp-stack.h" |
-#include "src/runtime/runtime.h" |
-#include "src/splay-tree-inl.h" |
-#include "src/string-search.h" |
-#include "src/unicode-decoder.h" |
- |
-#ifndef V8_INTERPRETED_REGEXP |
-#if V8_TARGET_ARCH_IA32 |
-#include "src/ia32/regexp-macro-assembler-ia32.h" // NOLINT |
-#elif V8_TARGET_ARCH_X64 |
-#include "src/x64/regexp-macro-assembler-x64.h" // NOLINT |
-#elif V8_TARGET_ARCH_ARM64 |
-#include "src/arm64/regexp-macro-assembler-arm64.h" // NOLINT |
-#elif V8_TARGET_ARCH_ARM |
-#include "src/arm/regexp-macro-assembler-arm.h" // NOLINT |
-#elif V8_TARGET_ARCH_PPC |
-#include "src/ppc/regexp-macro-assembler-ppc.h" // NOLINT |
-#elif V8_TARGET_ARCH_MIPS |
-#include "src/mips/regexp-macro-assembler-mips.h" // NOLINT |
-#elif V8_TARGET_ARCH_MIPS64 |
-#include "src/mips64/regexp-macro-assembler-mips64.h" // NOLINT |
-#elif V8_TARGET_ARCH_X87 |
-#include "src/x87/regexp-macro-assembler-x87.h" // NOLINT |
-#else |
-#error Unsupported target architecture. |
-#endif |
-#endif |
- |
-#include "src/interpreter-irregexp.h" |
- |
- |
-namespace v8 { |
-namespace internal { |
- |
-MaybeHandle<Object> RegExpImpl::CreateRegExpLiteral( |
- Handle<JSFunction> constructor, |
- Handle<String> pattern, |
- Handle<String> flags) { |
- // Call the construct code with 2 arguments. |
- Handle<Object> argv[] = { pattern, flags }; |
- return Execution::New(constructor, arraysize(argv), argv); |
-} |
- |
- |
-MUST_USE_RESULT |
-static inline MaybeHandle<Object> ThrowRegExpException( |
- Handle<JSRegExp> re, Handle<String> pattern, Handle<String> error_text) { |
- Isolate* isolate = re->GetIsolate(); |
- THROW_NEW_ERROR(isolate, NewSyntaxError(MessageTemplate::kMalformedRegExp, |
- pattern, error_text), |
- Object); |
-} |
- |
- |
-inline void ThrowRegExpException(Handle<JSRegExp> re, |
- Handle<String> error_text) { |
- USE(ThrowRegExpException(re, Handle<String>(re->Pattern()), error_text)); |
-} |
- |
- |
-ContainedInLattice AddRange(ContainedInLattice containment, |
- const int* ranges, |
- int ranges_length, |
- Interval new_range) { |
- DCHECK((ranges_length & 1) == 1); |
- DCHECK(ranges[ranges_length - 1] == String::kMaxUtf16CodeUnit + 1); |
- if (containment == kLatticeUnknown) return containment; |
- bool inside = false; |
- int last = 0; |
- for (int i = 0; i < ranges_length; inside = !inside, last = ranges[i], i++) { |
- // Consider the range from last to ranges[i]. |
- // We haven't got to the new range yet. |
- if (ranges[i] <= new_range.from()) continue; |
- // New range is wholly inside last-ranges[i]. Note that new_range.to() is |
- // inclusive, but the values in ranges are not. |
- if (last <= new_range.from() && new_range.to() < ranges[i]) { |
- return Combine(containment, inside ? kLatticeIn : kLatticeOut); |
- } |
- return kLatticeUnknown; |
- } |
- return containment; |
-} |
- |
- |
-// More makes code generation slower, less makes V8 benchmark score lower. |
-const int kMaxLookaheadForBoyerMoore = 8; |
-// In a 3-character pattern you can maximally step forwards 3 characters |
-// at a time, which is not always enough to pay for the extra logic. |
-const int kPatternTooShortForBoyerMoore = 2; |
- |
- |
-// Identifies the sort of regexps where the regexp engine is faster |
-// than the code used for atom matches. |
-static bool HasFewDifferentCharacters(Handle<String> pattern) { |
- int length = Min(kMaxLookaheadForBoyerMoore, pattern->length()); |
- if (length <= kPatternTooShortForBoyerMoore) return false; |
- const int kMod = 128; |
- bool character_found[kMod]; |
- int different = 0; |
- memset(&character_found[0], 0, sizeof(character_found)); |
- for (int i = 0; i < length; i++) { |
- int ch = (pattern->Get(i) & (kMod - 1)); |
- if (!character_found[ch]) { |
- character_found[ch] = true; |
- different++; |
- // We declare a regexp low-alphabet if it has at least 3 times as many |
- // characters as it has different characters. |
- if (different * 3 > length) return false; |
- } |
- } |
- return true; |
-} |
- |
- |
-// Generic RegExp methods. Dispatches to implementation specific methods. |
- |
- |
-MaybeHandle<Object> RegExpImpl::Compile(Handle<JSRegExp> re, |
- Handle<String> pattern, |
- JSRegExp::Flags flags) { |
- Isolate* isolate = re->GetIsolate(); |
- Zone zone; |
- CompilationCache* compilation_cache = isolate->compilation_cache(); |
- MaybeHandle<FixedArray> maybe_cached = |
- compilation_cache->LookupRegExp(pattern, flags); |
- Handle<FixedArray> cached; |
- bool in_cache = maybe_cached.ToHandle(&cached); |
- LOG(isolate, RegExpCompileEvent(re, in_cache)); |
- |
- Handle<Object> result; |
- if (in_cache) { |
- re->set_data(*cached); |
- return re; |
- } |
- pattern = String::Flatten(pattern); |
- PostponeInterruptsScope postpone(isolate); |
- RegExpCompileData parse_result; |
- FlatStringReader reader(isolate, pattern); |
- if (!RegExpParser::ParseRegExp(re->GetIsolate(), &zone, &reader, |
- flags.is_multiline(), flags.is_unicode(), |
- &parse_result)) { |
- // Throw an exception if we fail to parse the pattern. |
- return ThrowRegExpException(re, pattern, parse_result.error); |
- } |
- |
- bool has_been_compiled = false; |
- |
- if (parse_result.simple && |
- !flags.is_ignore_case() && |
- !flags.is_sticky() && |
- !HasFewDifferentCharacters(pattern)) { |
- // Parse-tree is a single atom that is equal to the pattern. |
- AtomCompile(re, pattern, flags, pattern); |
- has_been_compiled = true; |
- } else if (parse_result.tree->IsAtom() && |
- !flags.is_ignore_case() && |
- !flags.is_sticky() && |
- parse_result.capture_count == 0) { |
- RegExpAtom* atom = parse_result.tree->AsAtom(); |
- Vector<const uc16> atom_pattern = atom->data(); |
- Handle<String> atom_string; |
- ASSIGN_RETURN_ON_EXCEPTION( |
- isolate, atom_string, |
- isolate->factory()->NewStringFromTwoByte(atom_pattern), |
- Object); |
- if (!HasFewDifferentCharacters(atom_string)) { |
- AtomCompile(re, pattern, flags, atom_string); |
- has_been_compiled = true; |
- } |
- } |
- if (!has_been_compiled) { |
- IrregexpInitialize(re, pattern, flags, parse_result.capture_count); |
- } |
- DCHECK(re->data()->IsFixedArray()); |
- // Compilation succeeded so the data is set on the regexp |
- // and we can store it in the cache. |
- Handle<FixedArray> data(FixedArray::cast(re->data())); |
- compilation_cache->PutRegExp(pattern, flags, data); |
- |
- return re; |
-} |
- |
- |
-MaybeHandle<Object> RegExpImpl::Exec(Handle<JSRegExp> regexp, |
- Handle<String> subject, |
- int index, |
- Handle<JSArray> last_match_info) { |
- switch (regexp->TypeTag()) { |
- case JSRegExp::ATOM: |
- return AtomExec(regexp, subject, index, last_match_info); |
- case JSRegExp::IRREGEXP: { |
- return IrregexpExec(regexp, subject, index, last_match_info); |
- } |
- default: |
- UNREACHABLE(); |
- return MaybeHandle<Object>(); |
- } |
-} |
- |
- |
-// RegExp Atom implementation: Simple string search using indexOf. |
- |
- |
-void RegExpImpl::AtomCompile(Handle<JSRegExp> re, |
- Handle<String> pattern, |
- JSRegExp::Flags flags, |
- Handle<String> match_pattern) { |
- re->GetIsolate()->factory()->SetRegExpAtomData(re, |
- JSRegExp::ATOM, |
- pattern, |
- flags, |
- match_pattern); |
-} |
- |
- |
-static void SetAtomLastCapture(FixedArray* array, |
- String* subject, |
- int from, |
- int to) { |
- SealHandleScope shs(array->GetIsolate()); |
- RegExpImpl::SetLastCaptureCount(array, 2); |
- RegExpImpl::SetLastSubject(array, subject); |
- RegExpImpl::SetLastInput(array, subject); |
- RegExpImpl::SetCapture(array, 0, from); |
- RegExpImpl::SetCapture(array, 1, to); |
-} |
- |
- |
-int RegExpImpl::AtomExecRaw(Handle<JSRegExp> regexp, |
- Handle<String> subject, |
- int index, |
- int32_t* output, |
- int output_size) { |
- Isolate* isolate = regexp->GetIsolate(); |
- |
- DCHECK(0 <= index); |
- DCHECK(index <= subject->length()); |
- |
- subject = String::Flatten(subject); |
- DisallowHeapAllocation no_gc; // ensure vectors stay valid |
- |
- String* needle = String::cast(regexp->DataAt(JSRegExp::kAtomPatternIndex)); |
- int needle_len = needle->length(); |
- DCHECK(needle->IsFlat()); |
- DCHECK_LT(0, needle_len); |
- |
- if (index + needle_len > subject->length()) { |
- return RegExpImpl::RE_FAILURE; |
- } |
- |
- for (int i = 0; i < output_size; i += 2) { |
- String::FlatContent needle_content = needle->GetFlatContent(); |
- String::FlatContent subject_content = subject->GetFlatContent(); |
- DCHECK(needle_content.IsFlat()); |
- DCHECK(subject_content.IsFlat()); |
- // dispatch on type of strings |
- index = |
- (needle_content.IsOneByte() |
- ? (subject_content.IsOneByte() |
- ? SearchString(isolate, subject_content.ToOneByteVector(), |
- needle_content.ToOneByteVector(), index) |
- : SearchString(isolate, subject_content.ToUC16Vector(), |
- needle_content.ToOneByteVector(), index)) |
- : (subject_content.IsOneByte() |
- ? SearchString(isolate, subject_content.ToOneByteVector(), |
- needle_content.ToUC16Vector(), index) |
- : SearchString(isolate, subject_content.ToUC16Vector(), |
- needle_content.ToUC16Vector(), index))); |
- if (index == -1) { |
- return i / 2; // Return number of matches. |
- } else { |
- output[i] = index; |
- output[i+1] = index + needle_len; |
- index += needle_len; |
- } |
- } |
- return output_size / 2; |
-} |
- |
- |
-Handle<Object> RegExpImpl::AtomExec(Handle<JSRegExp> re, |
- Handle<String> subject, |
- int index, |
- Handle<JSArray> last_match_info) { |
- Isolate* isolate = re->GetIsolate(); |
- |
- static const int kNumRegisters = 2; |
- STATIC_ASSERT(kNumRegisters <= Isolate::kJSRegexpStaticOffsetsVectorSize); |
- int32_t* output_registers = isolate->jsregexp_static_offsets_vector(); |
- |
- int res = AtomExecRaw(re, subject, index, output_registers, kNumRegisters); |
- |
- if (res == RegExpImpl::RE_FAILURE) return isolate->factory()->null_value(); |
- |
- DCHECK_EQ(res, RegExpImpl::RE_SUCCESS); |
- SealHandleScope shs(isolate); |
- FixedArray* array = FixedArray::cast(last_match_info->elements()); |
- SetAtomLastCapture(array, *subject, output_registers[0], output_registers[1]); |
- return last_match_info; |
-} |
- |
- |
-// Irregexp implementation. |
- |
-// Ensures that the regexp object contains a compiled version of the |
-// source for either one-byte or two-byte subject strings. |
-// If the compiled version doesn't already exist, it is compiled |
-// from the source pattern. |
-// If compilation fails, an exception is thrown and this function |
-// returns false. |
-bool RegExpImpl::EnsureCompiledIrregexp(Handle<JSRegExp> re, |
- Handle<String> sample_subject, |
- bool is_one_byte) { |
- Object* compiled_code = re->DataAt(JSRegExp::code_index(is_one_byte)); |
-#ifdef V8_INTERPRETED_REGEXP |
- if (compiled_code->IsByteArray()) return true; |
-#else // V8_INTERPRETED_REGEXP (RegExp native code) |
- if (compiled_code->IsCode()) return true; |
-#endif |
- // We could potentially have marked this as flushable, but have kept |
- // a saved version if we did not flush it yet. |
- Object* saved_code = re->DataAt(JSRegExp::saved_code_index(is_one_byte)); |
- if (saved_code->IsCode()) { |
- // Reinstate the code in the original place. |
- re->SetDataAt(JSRegExp::code_index(is_one_byte), saved_code); |
- DCHECK(compiled_code->IsSmi()); |
- return true; |
- } |
- return CompileIrregexp(re, sample_subject, is_one_byte); |
-} |
- |
- |
-bool RegExpImpl::CompileIrregexp(Handle<JSRegExp> re, |
- Handle<String> sample_subject, |
- bool is_one_byte) { |
- // Compile the RegExp. |
- Isolate* isolate = re->GetIsolate(); |
- Zone zone; |
- PostponeInterruptsScope postpone(isolate); |
- // If we had a compilation error the last time this is saved at the |
- // saved code index. |
- Object* entry = re->DataAt(JSRegExp::code_index(is_one_byte)); |
- // When arriving here entry can only be a smi, either representing an |
- // uncompiled regexp, a previous compilation error, or code that has |
- // been flushed. |
- DCHECK(entry->IsSmi()); |
- int entry_value = Smi::cast(entry)->value(); |
- DCHECK(entry_value == JSRegExp::kUninitializedValue || |
- entry_value == JSRegExp::kCompilationErrorValue || |
- (entry_value < JSRegExp::kCodeAgeMask && entry_value >= 0)); |
- |
- if (entry_value == JSRegExp::kCompilationErrorValue) { |
- // A previous compilation failed and threw an error which we store in |
- // the saved code index (we store the error message, not the actual |
- // error). Recreate the error object and throw it. |
- Object* error_string = re->DataAt(JSRegExp::saved_code_index(is_one_byte)); |
- DCHECK(error_string->IsString()); |
- Handle<String> error_message(String::cast(error_string)); |
- ThrowRegExpException(re, error_message); |
- return false; |
- } |
- |
- JSRegExp::Flags flags = re->GetFlags(); |
- |
- Handle<String> pattern(re->Pattern()); |
- pattern = String::Flatten(pattern); |
- RegExpCompileData compile_data; |
- FlatStringReader reader(isolate, pattern); |
- if (!RegExpParser::ParseRegExp(isolate, &zone, &reader, flags.is_multiline(), |
- flags.is_unicode(), &compile_data)) { |
- // Throw an exception if we fail to parse the pattern. |
- // THIS SHOULD NOT HAPPEN. We already pre-parsed it successfully once. |
- USE(ThrowRegExpException(re, pattern, compile_data.error)); |
- return false; |
- } |
- RegExpEngine::CompilationResult result = RegExpEngine::Compile( |
- isolate, &zone, &compile_data, flags.is_ignore_case(), flags.is_global(), |
- flags.is_multiline(), flags.is_sticky(), pattern, sample_subject, |
- is_one_byte); |
- if (result.error_message != NULL) { |
- // Unable to compile regexp. |
- Handle<String> error_message = isolate->factory()->NewStringFromUtf8( |
- CStrVector(result.error_message)).ToHandleChecked(); |
- ThrowRegExpException(re, error_message); |
- return false; |
- } |
- |
- Handle<FixedArray> data = Handle<FixedArray>(FixedArray::cast(re->data())); |
- data->set(JSRegExp::code_index(is_one_byte), result.code); |
- int register_max = IrregexpMaxRegisterCount(*data); |
- if (result.num_registers > register_max) { |
- SetIrregexpMaxRegisterCount(*data, result.num_registers); |
- } |
- |
- return true; |
-} |
- |
- |
-int RegExpImpl::IrregexpMaxRegisterCount(FixedArray* re) { |
- return Smi::cast( |
- re->get(JSRegExp::kIrregexpMaxRegisterCountIndex))->value(); |
-} |
- |
- |
-void RegExpImpl::SetIrregexpMaxRegisterCount(FixedArray* re, int value) { |
- re->set(JSRegExp::kIrregexpMaxRegisterCountIndex, Smi::FromInt(value)); |
-} |
- |
- |
-int RegExpImpl::IrregexpNumberOfCaptures(FixedArray* re) { |
- return Smi::cast(re->get(JSRegExp::kIrregexpCaptureCountIndex))->value(); |
-} |
- |
- |
-int RegExpImpl::IrregexpNumberOfRegisters(FixedArray* re) { |
- return Smi::cast(re->get(JSRegExp::kIrregexpMaxRegisterCountIndex))->value(); |
-} |
- |
- |
-ByteArray* RegExpImpl::IrregexpByteCode(FixedArray* re, bool is_one_byte) { |
- return ByteArray::cast(re->get(JSRegExp::code_index(is_one_byte))); |
-} |
- |
- |
-Code* RegExpImpl::IrregexpNativeCode(FixedArray* re, bool is_one_byte) { |
- return Code::cast(re->get(JSRegExp::code_index(is_one_byte))); |
-} |
- |
- |
-void RegExpImpl::IrregexpInitialize(Handle<JSRegExp> re, |
- Handle<String> pattern, |
- JSRegExp::Flags flags, |
- int capture_count) { |
- // Initialize compiled code entries to null. |
- re->GetIsolate()->factory()->SetRegExpIrregexpData(re, |
- JSRegExp::IRREGEXP, |
- pattern, |
- flags, |
- capture_count); |
-} |
- |
- |
-int RegExpImpl::IrregexpPrepare(Handle<JSRegExp> regexp, |
- Handle<String> subject) { |
- subject = String::Flatten(subject); |
- |
- // Check representation of the underlying storage. |
- bool is_one_byte = subject->IsOneByteRepresentationUnderneath(); |
- if (!EnsureCompiledIrregexp(regexp, subject, is_one_byte)) return -1; |
- |
-#ifdef V8_INTERPRETED_REGEXP |
- // Byte-code regexp needs space allocated for all its registers. |
- // The result captures are copied to the start of the registers array |
- // if the match succeeds. This way those registers are not clobbered |
- // when we set the last match info from last successful match. |
- return IrregexpNumberOfRegisters(FixedArray::cast(regexp->data())) + |
- (IrregexpNumberOfCaptures(FixedArray::cast(regexp->data())) + 1) * 2; |
-#else // V8_INTERPRETED_REGEXP |
- // Native regexp only needs room to output captures. Registers are handled |
- // internally. |
- return (IrregexpNumberOfCaptures(FixedArray::cast(regexp->data())) + 1) * 2; |
-#endif // V8_INTERPRETED_REGEXP |
-} |
- |
- |
-int RegExpImpl::IrregexpExecRaw(Handle<JSRegExp> regexp, |
- Handle<String> subject, |
- int index, |
- int32_t* output, |
- int output_size) { |
- Isolate* isolate = regexp->GetIsolate(); |
- |
- Handle<FixedArray> irregexp(FixedArray::cast(regexp->data()), isolate); |
- |
- DCHECK(index >= 0); |
- DCHECK(index <= subject->length()); |
- DCHECK(subject->IsFlat()); |
- |
- bool is_one_byte = subject->IsOneByteRepresentationUnderneath(); |
- |
-#ifndef V8_INTERPRETED_REGEXP |
- DCHECK(output_size >= (IrregexpNumberOfCaptures(*irregexp) + 1) * 2); |
- do { |
- EnsureCompiledIrregexp(regexp, subject, is_one_byte); |
- Handle<Code> code(IrregexpNativeCode(*irregexp, is_one_byte), isolate); |
- // The stack is used to allocate registers for the compiled regexp code. |
- // This means that in case of failure, the output registers array is left |
- // untouched and contains the capture results from the previous successful |
- // match. We can use that to set the last match info lazily. |
- NativeRegExpMacroAssembler::Result res = |
- NativeRegExpMacroAssembler::Match(code, |
- subject, |
- output, |
- output_size, |
- index, |
- isolate); |
- if (res != NativeRegExpMacroAssembler::RETRY) { |
- DCHECK(res != NativeRegExpMacroAssembler::EXCEPTION || |
- isolate->has_pending_exception()); |
- STATIC_ASSERT( |
- static_cast<int>(NativeRegExpMacroAssembler::SUCCESS) == RE_SUCCESS); |
- STATIC_ASSERT( |
- static_cast<int>(NativeRegExpMacroAssembler::FAILURE) == RE_FAILURE); |
- STATIC_ASSERT(static_cast<int>(NativeRegExpMacroAssembler::EXCEPTION) |
- == RE_EXCEPTION); |
- return static_cast<IrregexpResult>(res); |
- } |
- // If result is RETRY, the string has changed representation, and we |
- // must restart from scratch. |
- // In this case, it means we must make sure we are prepared to handle |
- // the, potentially, different subject (the string can switch between |
- // being internal and external, and even between being Latin1 and UC16, |
- // but the characters are always the same). |
- IrregexpPrepare(regexp, subject); |
- is_one_byte = subject->IsOneByteRepresentationUnderneath(); |
- } while (true); |
- UNREACHABLE(); |
- return RE_EXCEPTION; |
-#else // V8_INTERPRETED_REGEXP |
- |
- DCHECK(output_size >= IrregexpNumberOfRegisters(*irregexp)); |
- // We must have done EnsureCompiledIrregexp, so we can get the number of |
- // registers. |
- int number_of_capture_registers = |
- (IrregexpNumberOfCaptures(*irregexp) + 1) * 2; |
- int32_t* raw_output = &output[number_of_capture_registers]; |
- // We do not touch the actual capture result registers until we know there |
- // has been a match so that we can use those capture results to set the |
- // last match info. |
- for (int i = number_of_capture_registers - 1; i >= 0; i--) { |
- raw_output[i] = -1; |
- } |
- Handle<ByteArray> byte_codes(IrregexpByteCode(*irregexp, is_one_byte), |
- isolate); |
- |
- IrregexpResult result = IrregexpInterpreter::Match(isolate, |
- byte_codes, |
- subject, |
- raw_output, |
- index); |
- if (result == RE_SUCCESS) { |
- // Copy capture results to the start of the registers array. |
- MemCopy(output, raw_output, number_of_capture_registers * sizeof(int32_t)); |
- } |
- if (result == RE_EXCEPTION) { |
- DCHECK(!isolate->has_pending_exception()); |
- isolate->StackOverflow(); |
- } |
- return result; |
-#endif // V8_INTERPRETED_REGEXP |
-} |
- |
- |
-MaybeHandle<Object> RegExpImpl::IrregexpExec(Handle<JSRegExp> regexp, |
- Handle<String> subject, |
- int previous_index, |
- Handle<JSArray> last_match_info) { |
- Isolate* isolate = regexp->GetIsolate(); |
- DCHECK_EQ(regexp->TypeTag(), JSRegExp::IRREGEXP); |
- |
- // Prepare space for the return values. |
-#if defined(V8_INTERPRETED_REGEXP) && defined(DEBUG) |
- if (FLAG_trace_regexp_bytecodes) { |
- String* pattern = regexp->Pattern(); |
- PrintF("\n\nRegexp match: /%s/\n\n", pattern->ToCString().get()); |
- PrintF("\n\nSubject string: '%s'\n\n", subject->ToCString().get()); |
- } |
-#endif |
- int required_registers = RegExpImpl::IrregexpPrepare(regexp, subject); |
- if (required_registers < 0) { |
- // Compiling failed with an exception. |
- DCHECK(isolate->has_pending_exception()); |
- return MaybeHandle<Object>(); |
- } |
- |
- int32_t* output_registers = NULL; |
- if (required_registers > Isolate::kJSRegexpStaticOffsetsVectorSize) { |
- output_registers = NewArray<int32_t>(required_registers); |
- } |
- base::SmartArrayPointer<int32_t> auto_release(output_registers); |
- if (output_registers == NULL) { |
- output_registers = isolate->jsregexp_static_offsets_vector(); |
- } |
- |
- int res = RegExpImpl::IrregexpExecRaw( |
- regexp, subject, previous_index, output_registers, required_registers); |
- if (res == RE_SUCCESS) { |
- int capture_count = |
- IrregexpNumberOfCaptures(FixedArray::cast(regexp->data())); |
- return SetLastMatchInfo( |
- last_match_info, subject, capture_count, output_registers); |
- } |
- if (res == RE_EXCEPTION) { |
- DCHECK(isolate->has_pending_exception()); |
- return MaybeHandle<Object>(); |
- } |
- DCHECK(res == RE_FAILURE); |
- return isolate->factory()->null_value(); |
-} |
- |
- |
-static void EnsureSize(Handle<JSArray> array, uint32_t minimum_size) { |
- if (static_cast<uint32_t>(array->elements()->length()) < minimum_size) { |
- JSArray::SetLength(array, minimum_size); |
- } |
-} |
- |
- |
-Handle<JSArray> RegExpImpl::SetLastMatchInfo(Handle<JSArray> last_match_info, |
- Handle<String> subject, |
- int capture_count, |
- int32_t* match) { |
- DCHECK(last_match_info->HasFastObjectElements()); |
- int capture_register_count = (capture_count + 1) * 2; |
- EnsureSize(last_match_info, capture_register_count + kLastMatchOverhead); |
- DisallowHeapAllocation no_allocation; |
- FixedArray* array = FixedArray::cast(last_match_info->elements()); |
- if (match != NULL) { |
- for (int i = 0; i < capture_register_count; i += 2) { |
- SetCapture(array, i, match[i]); |
- SetCapture(array, i + 1, match[i + 1]); |
- } |
- } |
- SetLastCaptureCount(array, capture_register_count); |
- SetLastSubject(array, *subject); |
- SetLastInput(array, *subject); |
- return last_match_info; |
-} |
- |
- |
-RegExpImpl::GlobalCache::GlobalCache(Handle<JSRegExp> regexp, |
- Handle<String> subject, |
- bool is_global, |
- Isolate* isolate) |
- : register_array_(NULL), |
- register_array_size_(0), |
- regexp_(regexp), |
- subject_(subject) { |
-#ifdef V8_INTERPRETED_REGEXP |
- bool interpreted = true; |
-#else |
- bool interpreted = false; |
-#endif // V8_INTERPRETED_REGEXP |
- |
- if (regexp_->TypeTag() == JSRegExp::ATOM) { |
- static const int kAtomRegistersPerMatch = 2; |
- registers_per_match_ = kAtomRegistersPerMatch; |
- // There is no distinction between interpreted and native for atom regexps. |
- interpreted = false; |
- } else { |
- registers_per_match_ = RegExpImpl::IrregexpPrepare(regexp_, subject_); |
- if (registers_per_match_ < 0) { |
- num_matches_ = -1; // Signal exception. |
- return; |
- } |
- } |
- |
- if (is_global && !interpreted) { |
- register_array_size_ = |
- Max(registers_per_match_, Isolate::kJSRegexpStaticOffsetsVectorSize); |
- max_matches_ = register_array_size_ / registers_per_match_; |
- } else { |
- // Global loop in interpreted regexp is not implemented. We choose |
- // the size of the offsets vector so that it can only store one match. |
- register_array_size_ = registers_per_match_; |
- max_matches_ = 1; |
- } |
- |
- if (register_array_size_ > Isolate::kJSRegexpStaticOffsetsVectorSize) { |
- register_array_ = NewArray<int32_t>(register_array_size_); |
- } else { |
- register_array_ = isolate->jsregexp_static_offsets_vector(); |
- } |
- |
- // Set state so that fetching the results the first time triggers a call |
- // to the compiled regexp. |
- current_match_index_ = max_matches_ - 1; |
- num_matches_ = max_matches_; |
- DCHECK(registers_per_match_ >= 2); // Each match has at least one capture. |
- DCHECK_GE(register_array_size_, registers_per_match_); |
- int32_t* last_match = |
- ®ister_array_[current_match_index_ * registers_per_match_]; |
- last_match[0] = -1; |
- last_match[1] = 0; |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Implementation of the Irregexp regular expression engine. |
-// |
-// The Irregexp regular expression engine is intended to be a complete |
-// implementation of ECMAScript regular expressions. It generates either |
-// bytecodes or native code. |
- |
-// The Irregexp regexp engine is structured in three steps. |
-// 1) The parser generates an abstract syntax tree. See ast.cc. |
-// 2) From the AST a node network is created. The nodes are all |
-// subclasses of RegExpNode. The nodes represent states when |
-// executing a regular expression. Several optimizations are |
-// performed on the node network. |
-// 3) From the nodes we generate either byte codes or native code |
-// that can actually execute the regular expression (perform |
-// the search). The code generation step is described in more |
-// detail below. |
- |
-// Code generation. |
-// |
-// The nodes are divided into four main categories. |
-// * Choice nodes |
-// These represent places where the regular expression can |
-// match in more than one way. For example on entry to an |
-// alternation (foo|bar) or a repetition (*, +, ? or {}). |
-// * Action nodes |
-// These represent places where some action should be |
-// performed. Examples include recording the current position |
-// in the input string to a register (in order to implement |
-// captures) or other actions on register for example in order |
-// to implement the counters needed for {} repetitions. |
-// * Matching nodes |
-// These attempt to match some element part of the input string. |
-// Examples of elements include character classes, plain strings |
-// or back references. |
-// * End nodes |
-// These are used to implement the actions required on finding |
-// a successful match or failing to find a match. |
-// |
-// The code generated (whether as byte codes or native code) maintains |
-// some state as it runs. This consists of the following elements: |
-// |
-// * The capture registers. Used for string captures. |
-// * Other registers. Used for counters etc. |
-// * The current position. |
-// * The stack of backtracking information. Used when a matching node |
-// fails to find a match and needs to try an alternative. |
-// |
-// Conceptual regular expression execution model: |
-// |
-// There is a simple conceptual model of regular expression execution |
-// which will be presented first. The actual code generated is a more |
-// efficient simulation of the simple conceptual model: |
-// |
-// * Choice nodes are implemented as follows: |
-// For each choice except the last { |
-// push current position |
-// push backtrack code location |
-// <generate code to test for choice> |
-// backtrack code location: |
-// pop current position |
-// } |
-// <generate code to test for last choice> |
-// |
-// * Actions nodes are generated as follows |
-// <push affected registers on backtrack stack> |
-// <generate code to perform action> |
-// push backtrack code location |
-// <generate code to test for following nodes> |
-// backtrack code location: |
-// <pop affected registers to restore their state> |
-// <pop backtrack location from stack and go to it> |
-// |
-// * Matching nodes are generated as follows: |
-// if input string matches at current position |
-// update current position |
-// <generate code to test for following nodes> |
-// else |
-// <pop backtrack location from stack and go to it> |
-// |
-// Thus it can be seen that the current position is saved and restored |
-// by the choice nodes, whereas the registers are saved and restored by |
-// by the action nodes that manipulate them. |
-// |
-// The other interesting aspect of this model is that nodes are generated |
-// at the point where they are needed by a recursive call to Emit(). If |
-// the node has already been code generated then the Emit() call will |
-// generate a jump to the previously generated code instead. In order to |
-// limit recursion it is possible for the Emit() function to put the node |
-// on a work list for later generation and instead generate a jump. The |
-// destination of the jump is resolved later when the code is generated. |
-// |
-// Actual regular expression code generation. |
-// |
-// Code generation is actually more complicated than the above. In order |
-// to improve the efficiency of the generated code some optimizations are |
-// performed |
-// |
-// * Choice nodes have 1-character lookahead. |
-// A choice node looks at the following character and eliminates some of |
-// the choices immediately based on that character. This is not yet |
-// implemented. |
-// * Simple greedy loops store reduced backtracking information. |
-// A quantifier like /.*foo/m will greedily match the whole input. It will |
-// then need to backtrack to a point where it can match "foo". The naive |
-// implementation of this would push each character position onto the |
-// backtracking stack, then pop them off one by one. This would use space |
-// proportional to the length of the input string. However since the "." |
-// can only match in one way and always has a constant length (in this case |
-// of 1) it suffices to store the current position on the top of the stack |
-// once. Matching now becomes merely incrementing the current position and |
-// backtracking becomes decrementing the current position and checking the |
-// result against the stored current position. This is faster and saves |
-// space. |
-// * The current state is virtualized. |
-// This is used to defer expensive operations until it is clear that they |
-// are needed and to generate code for a node more than once, allowing |
-// specialized an efficient versions of the code to be created. This is |
-// explained in the section below. |
-// |
-// Execution state virtualization. |
-// |
-// Instead of emitting code, nodes that manipulate the state can record their |
-// manipulation in an object called the Trace. The Trace object can record a |
-// current position offset, an optional backtrack code location on the top of |
-// the virtualized backtrack stack and some register changes. When a node is |
-// to be emitted it can flush the Trace or update it. Flushing the Trace |
-// will emit code to bring the actual state into line with the virtual state. |
-// Avoiding flushing the state can postpone some work (e.g. updates of capture |
-// registers). Postponing work can save time when executing the regular |
-// expression since it may be found that the work never has to be done as a |
-// failure to match can occur. In addition it is much faster to jump to a |
-// known backtrack code location than it is to pop an unknown backtrack |
-// location from the stack and jump there. |
-// |
-// The virtual state found in the Trace affects code generation. For example |
-// the virtual state contains the difference between the actual current |
-// position and the virtual current position, and matching code needs to use |
-// this offset to attempt a match in the correct location of the input |
-// string. Therefore code generated for a non-trivial trace is specialized |
-// to that trace. The code generator therefore has the ability to generate |
-// code for each node several times. In order to limit the size of the |
-// generated code there is an arbitrary limit on how many specialized sets of |
-// code may be generated for a given node. If the limit is reached, the |
-// trace is flushed and a generic version of the code for a node is emitted. |
-// This is subsequently used for that node. The code emitted for non-generic |
-// trace is not recorded in the node and so it cannot currently be reused in |
-// the event that code generation is requested for an identical trace. |
- |
- |
-void RegExpTree::AppendToText(RegExpText* text, Zone* zone) { |
- UNREACHABLE(); |
-} |
- |
- |
-void RegExpAtom::AppendToText(RegExpText* text, Zone* zone) { |
- text->AddElement(TextElement::Atom(this), zone); |
-} |
- |
- |
-void RegExpCharacterClass::AppendToText(RegExpText* text, Zone* zone) { |
- text->AddElement(TextElement::CharClass(this), zone); |
-} |
- |
- |
-void RegExpText::AppendToText(RegExpText* text, Zone* zone) { |
- for (int i = 0; i < elements()->length(); i++) |
- text->AddElement(elements()->at(i), zone); |
-} |
- |
- |
-TextElement TextElement::Atom(RegExpAtom* atom) { |
- return TextElement(ATOM, atom); |
-} |
- |
- |
-TextElement TextElement::CharClass(RegExpCharacterClass* char_class) { |
- return TextElement(CHAR_CLASS, char_class); |
-} |
- |
- |
-int TextElement::length() const { |
- switch (text_type()) { |
- case ATOM: |
- return atom()->length(); |
- |
- case CHAR_CLASS: |
- return 1; |
- } |
- UNREACHABLE(); |
- return 0; |
-} |
- |
- |
-DispatchTable* ChoiceNode::GetTable(bool ignore_case) { |
- if (table_ == NULL) { |
- table_ = new(zone()) DispatchTable(zone()); |
- DispatchTableConstructor cons(table_, ignore_case, zone()); |
- cons.BuildTable(this); |
- } |
- return table_; |
-} |
- |
- |
-class FrequencyCollator { |
- public: |
- FrequencyCollator() : total_samples_(0) { |
- for (int i = 0; i < RegExpMacroAssembler::kTableSize; i++) { |
- frequencies_[i] = CharacterFrequency(i); |
- } |
- } |
- |
- void CountCharacter(int character) { |
- int index = (character & RegExpMacroAssembler::kTableMask); |
- frequencies_[index].Increment(); |
- total_samples_++; |
- } |
- |
- // Does not measure in percent, but rather per-128 (the table size from the |
- // regexp macro assembler). |
- int Frequency(int in_character) { |
- DCHECK((in_character & RegExpMacroAssembler::kTableMask) == in_character); |
- if (total_samples_ < 1) return 1; // Division by zero. |
- int freq_in_per128 = |
- (frequencies_[in_character].counter() * 128) / total_samples_; |
- return freq_in_per128; |
- } |
- |
- private: |
- class CharacterFrequency { |
- public: |
- CharacterFrequency() : counter_(0), character_(-1) { } |
- explicit CharacterFrequency(int character) |
- : counter_(0), character_(character) { } |
- |
- void Increment() { counter_++; } |
- int counter() { return counter_; } |
- int character() { return character_; } |
- |
- private: |
- int counter_; |
- int character_; |
- }; |
- |
- |
- private: |
- CharacterFrequency frequencies_[RegExpMacroAssembler::kTableSize]; |
- int total_samples_; |
-}; |
- |
- |
-class RegExpCompiler { |
- public: |
- RegExpCompiler(Isolate* isolate, Zone* zone, int capture_count, |
- bool ignore_case, bool is_one_byte); |
- |
- int AllocateRegister() { |
- if (next_register_ >= RegExpMacroAssembler::kMaxRegister) { |
- reg_exp_too_big_ = true; |
- return next_register_; |
- } |
- return next_register_++; |
- } |
- |
- RegExpEngine::CompilationResult Assemble(RegExpMacroAssembler* assembler, |
- RegExpNode* start, |
- int capture_count, |
- Handle<String> pattern); |
- |
- inline void AddWork(RegExpNode* node) { |
- if (!node->on_work_list() && !node->label()->is_bound()) { |
- node->set_on_work_list(true); |
- work_list_->Add(node); |
- } |
- } |
- |
- static const int kImplementationOffset = 0; |
- static const int kNumberOfRegistersOffset = 0; |
- static const int kCodeOffset = 1; |
- |
- RegExpMacroAssembler* macro_assembler() { return macro_assembler_; } |
- EndNode* accept() { return accept_; } |
- |
- static const int kMaxRecursion = 100; |
- inline int recursion_depth() { return recursion_depth_; } |
- inline void IncrementRecursionDepth() { recursion_depth_++; } |
- inline void DecrementRecursionDepth() { recursion_depth_--; } |
- |
- void SetRegExpTooBig() { reg_exp_too_big_ = true; } |
- |
- inline bool ignore_case() { return ignore_case_; } |
- inline bool one_byte() { return one_byte_; } |
- inline bool optimize() { return optimize_; } |
- inline void set_optimize(bool value) { optimize_ = value; } |
- inline bool limiting_recursion() { return limiting_recursion_; } |
- inline void set_limiting_recursion(bool value) { |
- limiting_recursion_ = value; |
- } |
- FrequencyCollator* frequency_collator() { return &frequency_collator_; } |
- |
- int current_expansion_factor() { return current_expansion_factor_; } |
- void set_current_expansion_factor(int value) { |
- current_expansion_factor_ = value; |
- } |
- |
- Isolate* isolate() const { return isolate_; } |
- Zone* zone() const { return zone_; } |
- |
- static const int kNoRegister = -1; |
- |
- private: |
- EndNode* accept_; |
- int next_register_; |
- List<RegExpNode*>* work_list_; |
- int recursion_depth_; |
- RegExpMacroAssembler* macro_assembler_; |
- bool ignore_case_; |
- bool one_byte_; |
- bool reg_exp_too_big_; |
- bool limiting_recursion_; |
- bool optimize_; |
- int current_expansion_factor_; |
- FrequencyCollator frequency_collator_; |
- Isolate* isolate_; |
- Zone* zone_; |
-}; |
- |
- |
-class RecursionCheck { |
- public: |
- explicit RecursionCheck(RegExpCompiler* compiler) : compiler_(compiler) { |
- compiler->IncrementRecursionDepth(); |
- } |
- ~RecursionCheck() { compiler_->DecrementRecursionDepth(); } |
- private: |
- RegExpCompiler* compiler_; |
-}; |
- |
- |
-static RegExpEngine::CompilationResult IrregexpRegExpTooBig(Isolate* isolate) { |
- return RegExpEngine::CompilationResult(isolate, "RegExp too big"); |
-} |
- |
- |
-// Attempts to compile the regexp using an Irregexp code generator. Returns |
-// a fixed array or a null handle depending on whether it succeeded. |
-RegExpCompiler::RegExpCompiler(Isolate* isolate, Zone* zone, int capture_count, |
- bool ignore_case, bool one_byte) |
- : next_register_(2 * (capture_count + 1)), |
- work_list_(NULL), |
- recursion_depth_(0), |
- ignore_case_(ignore_case), |
- one_byte_(one_byte), |
- reg_exp_too_big_(false), |
- limiting_recursion_(false), |
- optimize_(FLAG_regexp_optimization), |
- current_expansion_factor_(1), |
- frequency_collator_(), |
- isolate_(isolate), |
- zone_(zone) { |
- accept_ = new(zone) EndNode(EndNode::ACCEPT, zone); |
- DCHECK(next_register_ - 1 <= RegExpMacroAssembler::kMaxRegister); |
-} |
- |
- |
-RegExpEngine::CompilationResult RegExpCompiler::Assemble( |
- RegExpMacroAssembler* macro_assembler, |
- RegExpNode* start, |
- int capture_count, |
- Handle<String> pattern) { |
- Heap* heap = pattern->GetHeap(); |
- |
-#ifdef DEBUG |
- if (FLAG_trace_regexp_assembler) |
- macro_assembler_ = |
- new RegExpMacroAssemblerTracer(isolate(), macro_assembler); |
- else |
-#endif |
- macro_assembler_ = macro_assembler; |
- |
- List <RegExpNode*> work_list(0); |
- work_list_ = &work_list; |
- Label fail; |
- macro_assembler_->PushBacktrack(&fail); |
- Trace new_trace; |
- start->Emit(this, &new_trace); |
- macro_assembler_->Bind(&fail); |
- macro_assembler_->Fail(); |
- while (!work_list.is_empty()) { |
- RegExpNode* node = work_list.RemoveLast(); |
- node->set_on_work_list(false); |
- if (!node->label()->is_bound()) node->Emit(this, &new_trace); |
- } |
- if (reg_exp_too_big_) { |
- macro_assembler_->AbortedCodeGeneration(); |
- return IrregexpRegExpTooBig(isolate_); |
- } |
- |
- Handle<HeapObject> code = macro_assembler_->GetCode(pattern); |
- heap->IncreaseTotalRegexpCodeGenerated(code->Size()); |
- work_list_ = NULL; |
-#ifdef ENABLE_DISASSEMBLER |
- if (FLAG_print_code) { |
- CodeTracer::Scope trace_scope(heap->isolate()->GetCodeTracer()); |
- OFStream os(trace_scope.file()); |
- Handle<Code>::cast(code)->Disassemble(pattern->ToCString().get(), os); |
- } |
-#endif |
-#ifdef DEBUG |
- if (FLAG_trace_regexp_assembler) { |
- delete macro_assembler_; |
- } |
-#endif |
- return RegExpEngine::CompilationResult(*code, next_register_); |
-} |
- |
- |
-bool Trace::DeferredAction::Mentions(int that) { |
- if (action_type() == ActionNode::CLEAR_CAPTURES) { |
- Interval range = static_cast<DeferredClearCaptures*>(this)->range(); |
- return range.Contains(that); |
- } else { |
- return reg() == that; |
- } |
-} |
- |
- |
-bool Trace::mentions_reg(int reg) { |
- for (DeferredAction* action = actions_; |
- action != NULL; |
- action = action->next()) { |
- if (action->Mentions(reg)) |
- return true; |
- } |
- return false; |
-} |
- |
- |
-bool Trace::GetStoredPosition(int reg, int* cp_offset) { |
- DCHECK_EQ(0, *cp_offset); |
- for (DeferredAction* action = actions_; |
- action != NULL; |
- action = action->next()) { |
- if (action->Mentions(reg)) { |
- if (action->action_type() == ActionNode::STORE_POSITION) { |
- *cp_offset = static_cast<DeferredCapture*>(action)->cp_offset(); |
- return true; |
- } else { |
- return false; |
- } |
- } |
- } |
- return false; |
-} |
- |
- |
-int Trace::FindAffectedRegisters(OutSet* affected_registers, |
- Zone* zone) { |
- int max_register = RegExpCompiler::kNoRegister; |
- for (DeferredAction* action = actions_; |
- action != NULL; |
- action = action->next()) { |
- if (action->action_type() == ActionNode::CLEAR_CAPTURES) { |
- Interval range = static_cast<DeferredClearCaptures*>(action)->range(); |
- for (int i = range.from(); i <= range.to(); i++) |
- affected_registers->Set(i, zone); |
- if (range.to() > max_register) max_register = range.to(); |
- } else { |
- affected_registers->Set(action->reg(), zone); |
- if (action->reg() > max_register) max_register = action->reg(); |
- } |
- } |
- return max_register; |
-} |
- |
- |
-void Trace::RestoreAffectedRegisters(RegExpMacroAssembler* assembler, |
- int max_register, |
- const OutSet& registers_to_pop, |
- const OutSet& registers_to_clear) { |
- for (int reg = max_register; reg >= 0; reg--) { |
- if (registers_to_pop.Get(reg)) { |
- assembler->PopRegister(reg); |
- } else if (registers_to_clear.Get(reg)) { |
- int clear_to = reg; |
- while (reg > 0 && registers_to_clear.Get(reg - 1)) { |
- reg--; |
- } |
- assembler->ClearRegisters(reg, clear_to); |
- } |
- } |
-} |
- |
- |
-void Trace::PerformDeferredActions(RegExpMacroAssembler* assembler, |
- int max_register, |
- const OutSet& affected_registers, |
- OutSet* registers_to_pop, |
- OutSet* registers_to_clear, |
- Zone* zone) { |
- // The "+1" is to avoid a push_limit of zero if stack_limit_slack() is 1. |
- const int push_limit = (assembler->stack_limit_slack() + 1) / 2; |
- |
- // Count pushes performed to force a stack limit check occasionally. |
- int pushes = 0; |
- |
- for (int reg = 0; reg <= max_register; reg++) { |
- if (!affected_registers.Get(reg)) { |
- continue; |
- } |
- |
- // The chronologically first deferred action in the trace |
- // is used to infer the action needed to restore a register |
- // to its previous state (or not, if it's safe to ignore it). |
- enum DeferredActionUndoType { IGNORE, RESTORE, CLEAR }; |
- DeferredActionUndoType undo_action = IGNORE; |
- |
- int value = 0; |
- bool absolute = false; |
- bool clear = false; |
- int store_position = -1; |
- // This is a little tricky because we are scanning the actions in reverse |
- // historical order (newest first). |
- for (DeferredAction* action = actions_; |
- action != NULL; |
- action = action->next()) { |
- if (action->Mentions(reg)) { |
- switch (action->action_type()) { |
- case ActionNode::SET_REGISTER: { |
- Trace::DeferredSetRegister* psr = |
- static_cast<Trace::DeferredSetRegister*>(action); |
- if (!absolute) { |
- value += psr->value(); |
- absolute = true; |
- } |
- // SET_REGISTER is currently only used for newly introduced loop |
- // counters. They can have a significant previous value if they |
- // occour in a loop. TODO(lrn): Propagate this information, so |
- // we can set undo_action to IGNORE if we know there is no value to |
- // restore. |
- undo_action = RESTORE; |
- DCHECK_EQ(store_position, -1); |
- DCHECK(!clear); |
- break; |
- } |
- case ActionNode::INCREMENT_REGISTER: |
- if (!absolute) { |
- value++; |
- } |
- DCHECK_EQ(store_position, -1); |
- DCHECK(!clear); |
- undo_action = RESTORE; |
- break; |
- case ActionNode::STORE_POSITION: { |
- Trace::DeferredCapture* pc = |
- static_cast<Trace::DeferredCapture*>(action); |
- if (!clear && store_position == -1) { |
- store_position = pc->cp_offset(); |
- } |
- |
- // For captures we know that stores and clears alternate. |
- // Other register, are never cleared, and if the occur |
- // inside a loop, they might be assigned more than once. |
- if (reg <= 1) { |
- // Registers zero and one, aka "capture zero", is |
- // always set correctly if we succeed. There is no |
- // need to undo a setting on backtrack, because we |
- // will set it again or fail. |
- undo_action = IGNORE; |
- } else { |
- undo_action = pc->is_capture() ? CLEAR : RESTORE; |
- } |
- DCHECK(!absolute); |
- DCHECK_EQ(value, 0); |
- break; |
- } |
- case ActionNode::CLEAR_CAPTURES: { |
- // Since we're scanning in reverse order, if we've already |
- // set the position we have to ignore historically earlier |
- // clearing operations. |
- if (store_position == -1) { |
- clear = true; |
- } |
- undo_action = RESTORE; |
- DCHECK(!absolute); |
- DCHECK_EQ(value, 0); |
- break; |
- } |
- default: |
- UNREACHABLE(); |
- break; |
- } |
- } |
- } |
- // Prepare for the undo-action (e.g., push if it's going to be popped). |
- if (undo_action == RESTORE) { |
- pushes++; |
- RegExpMacroAssembler::StackCheckFlag stack_check = |
- RegExpMacroAssembler::kNoStackLimitCheck; |
- if (pushes == push_limit) { |
- stack_check = RegExpMacroAssembler::kCheckStackLimit; |
- pushes = 0; |
- } |
- |
- assembler->PushRegister(reg, stack_check); |
- registers_to_pop->Set(reg, zone); |
- } else if (undo_action == CLEAR) { |
- registers_to_clear->Set(reg, zone); |
- } |
- // Perform the chronologically last action (or accumulated increment) |
- // for the register. |
- if (store_position != -1) { |
- assembler->WriteCurrentPositionToRegister(reg, store_position); |
- } else if (clear) { |
- assembler->ClearRegisters(reg, reg); |
- } else if (absolute) { |
- assembler->SetRegister(reg, value); |
- } else if (value != 0) { |
- assembler->AdvanceRegister(reg, value); |
- } |
- } |
-} |
- |
- |
-// This is called as we come into a loop choice node and some other tricky |
-// nodes. It normalizes the state of the code generator to ensure we can |
-// generate generic code. |
-void Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- |
- DCHECK(!is_trivial()); |
- |
- if (actions_ == NULL && backtrack() == NULL) { |
- // Here we just have some deferred cp advances to fix and we are back to |
- // a normal situation. We may also have to forget some information gained |
- // through a quick check that was already performed. |
- if (cp_offset_ != 0) assembler->AdvanceCurrentPosition(cp_offset_); |
- // Create a new trivial state and generate the node with that. |
- Trace new_state; |
- successor->Emit(compiler, &new_state); |
- return; |
- } |
- |
- // Generate deferred actions here along with code to undo them again. |
- OutSet affected_registers; |
- |
- if (backtrack() != NULL) { |
- // Here we have a concrete backtrack location. These are set up by choice |
- // nodes and so they indicate that we have a deferred save of the current |
- // position which we may need to emit here. |
- assembler->PushCurrentPosition(); |
- } |
- |
- int max_register = FindAffectedRegisters(&affected_registers, |
- compiler->zone()); |
- OutSet registers_to_pop; |
- OutSet registers_to_clear; |
- PerformDeferredActions(assembler, |
- max_register, |
- affected_registers, |
- ®isters_to_pop, |
- ®isters_to_clear, |
- compiler->zone()); |
- if (cp_offset_ != 0) { |
- assembler->AdvanceCurrentPosition(cp_offset_); |
- } |
- |
- // Create a new trivial state and generate the node with that. |
- Label undo; |
- assembler->PushBacktrack(&undo); |
- if (successor->KeepRecursing(compiler)) { |
- Trace new_state; |
- successor->Emit(compiler, &new_state); |
- } else { |
- compiler->AddWork(successor); |
- assembler->GoTo(successor->label()); |
- } |
- |
- // On backtrack we need to restore state. |
- assembler->Bind(&undo); |
- RestoreAffectedRegisters(assembler, |
- max_register, |
- registers_to_pop, |
- registers_to_clear); |
- if (backtrack() == NULL) { |
- assembler->Backtrack(); |
- } else { |
- assembler->PopCurrentPosition(); |
- assembler->GoTo(backtrack()); |
- } |
-} |
- |
- |
-void NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- |
- // Omit flushing the trace. We discard the entire stack frame anyway. |
- |
- if (!label()->is_bound()) { |
- // We are completely independent of the trace, since we ignore it, |
- // so this code can be used as the generic version. |
- assembler->Bind(label()); |
- } |
- |
- // Throw away everything on the backtrack stack since the start |
- // of the negative submatch and restore the character position. |
- assembler->ReadCurrentPositionFromRegister(current_position_register_); |
- assembler->ReadStackPointerFromRegister(stack_pointer_register_); |
- if (clear_capture_count_ > 0) { |
- // Clear any captures that might have been performed during the success |
- // of the body of the negative look-ahead. |
- int clear_capture_end = clear_capture_start_ + clear_capture_count_ - 1; |
- assembler->ClearRegisters(clear_capture_start_, clear_capture_end); |
- } |
- // Now that we have unwound the stack we find at the top of the stack the |
- // backtrack that the BeginSubmatch node got. |
- assembler->Backtrack(); |
-} |
- |
- |
-void EndNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- return; |
- } |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- if (!label()->is_bound()) { |
- assembler->Bind(label()); |
- } |
- switch (action_) { |
- case ACCEPT: |
- assembler->Succeed(); |
- return; |
- case BACKTRACK: |
- assembler->GoTo(trace->backtrack()); |
- return; |
- case NEGATIVE_SUBMATCH_SUCCESS: |
- // This case is handled in a different virtual method. |
- UNREACHABLE(); |
- } |
- UNIMPLEMENTED(); |
-} |
- |
- |
-void GuardedAlternative::AddGuard(Guard* guard, Zone* zone) { |
- if (guards_ == NULL) |
- guards_ = new(zone) ZoneList<Guard*>(1, zone); |
- guards_->Add(guard, zone); |
-} |
- |
- |
-ActionNode* ActionNode::SetRegister(int reg, |
- int val, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(SET_REGISTER, on_success); |
- result->data_.u_store_register.reg = reg; |
- result->data_.u_store_register.value = val; |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::IncrementRegister(int reg, RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(INCREMENT_REGISTER, on_success); |
- result->data_.u_increment_register.reg = reg; |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::StorePosition(int reg, |
- bool is_capture, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(STORE_POSITION, on_success); |
- result->data_.u_position_register.reg = reg; |
- result->data_.u_position_register.is_capture = is_capture; |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::ClearCaptures(Interval range, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(CLEAR_CAPTURES, on_success); |
- result->data_.u_clear_captures.range_from = range.from(); |
- result->data_.u_clear_captures.range_to = range.to(); |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::BeginSubmatch(int stack_reg, |
- int position_reg, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(BEGIN_SUBMATCH, on_success); |
- result->data_.u_submatch.stack_pointer_register = stack_reg; |
- result->data_.u_submatch.current_position_register = position_reg; |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::PositiveSubmatchSuccess(int stack_reg, |
- int position_reg, |
- int clear_register_count, |
- int clear_register_from, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(POSITIVE_SUBMATCH_SUCCESS, on_success); |
- result->data_.u_submatch.stack_pointer_register = stack_reg; |
- result->data_.u_submatch.current_position_register = position_reg; |
- result->data_.u_submatch.clear_register_count = clear_register_count; |
- result->data_.u_submatch.clear_register_from = clear_register_from; |
- return result; |
-} |
- |
- |
-ActionNode* ActionNode::EmptyMatchCheck(int start_register, |
- int repetition_register, |
- int repetition_limit, |
- RegExpNode* on_success) { |
- ActionNode* result = |
- new(on_success->zone()) ActionNode(EMPTY_MATCH_CHECK, on_success); |
- result->data_.u_empty_match_check.start_register = start_register; |
- result->data_.u_empty_match_check.repetition_register = repetition_register; |
- result->data_.u_empty_match_check.repetition_limit = repetition_limit; |
- return result; |
-} |
- |
- |
-#define DEFINE_ACCEPT(Type) \ |
- void Type##Node::Accept(NodeVisitor* visitor) { \ |
- visitor->Visit##Type(this); \ |
- } |
-FOR_EACH_NODE_TYPE(DEFINE_ACCEPT) |
-#undef DEFINE_ACCEPT |
- |
- |
-void LoopChoiceNode::Accept(NodeVisitor* visitor) { |
- visitor->VisitLoopChoice(this); |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Emit code. |
- |
- |
-void ChoiceNode::GenerateGuard(RegExpMacroAssembler* macro_assembler, |
- Guard* guard, |
- Trace* trace) { |
- switch (guard->op()) { |
- case Guard::LT: |
- DCHECK(!trace->mentions_reg(guard->reg())); |
- macro_assembler->IfRegisterGE(guard->reg(), |
- guard->value(), |
- trace->backtrack()); |
- break; |
- case Guard::GEQ: |
- DCHECK(!trace->mentions_reg(guard->reg())); |
- macro_assembler->IfRegisterLT(guard->reg(), |
- guard->value(), |
- trace->backtrack()); |
- break; |
- } |
-} |
- |
- |
-// Returns the number of characters in the equivalence class, omitting those |
-// that cannot occur in the source string because it is Latin1. |
-static int GetCaseIndependentLetters(Isolate* isolate, uc16 character, |
- bool one_byte_subject, |
- unibrow::uchar* letters) { |
- int length = |
- isolate->jsregexp_uncanonicalize()->get(character, '\0', letters); |
- // Unibrow returns 0 or 1 for characters where case independence is |
- // trivial. |
- if (length == 0) { |
- letters[0] = character; |
- length = 1; |
- } |
- |
- if (one_byte_subject) { |
- int new_length = 0; |
- for (int i = 0; i < length; i++) { |
- if (letters[i] <= String::kMaxOneByteCharCode) { |
- letters[new_length++] = letters[i]; |
- } |
- } |
- length = new_length; |
- } |
- |
- return length; |
-} |
- |
- |
-static inline bool EmitSimpleCharacter(Isolate* isolate, |
- RegExpCompiler* compiler, |
- uc16 c, |
- Label* on_failure, |
- int cp_offset, |
- bool check, |
- bool preloaded) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- bool bound_checked = false; |
- if (!preloaded) { |
- assembler->LoadCurrentCharacter( |
- cp_offset, |
- on_failure, |
- check); |
- bound_checked = true; |
- } |
- assembler->CheckNotCharacter(c, on_failure); |
- return bound_checked; |
-} |
- |
- |
-// Only emits non-letters (things that don't have case). Only used for case |
-// independent matches. |
-static inline bool EmitAtomNonLetter(Isolate* isolate, |
- RegExpCompiler* compiler, |
- uc16 c, |
- Label* on_failure, |
- int cp_offset, |
- bool check, |
- bool preloaded) { |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- bool one_byte = compiler->one_byte(); |
- unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- int length = GetCaseIndependentLetters(isolate, c, one_byte, chars); |
- if (length < 1) { |
- // This can't match. Must be an one-byte subject and a non-one-byte |
- // character. We do not need to do anything since the one-byte pass |
- // already handled this. |
- return false; // Bounds not checked. |
- } |
- bool checked = false; |
- // We handle the length > 1 case in a later pass. |
- if (length == 1) { |
- if (one_byte && c > String::kMaxOneByteCharCodeU) { |
- // Can't match - see above. |
- return false; // Bounds not checked. |
- } |
- if (!preloaded) { |
- macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check); |
- checked = check; |
- } |
- macro_assembler->CheckNotCharacter(c, on_failure); |
- } |
- return checked; |
-} |
- |
- |
-static bool ShortCutEmitCharacterPair(RegExpMacroAssembler* macro_assembler, |
- bool one_byte, uc16 c1, uc16 c2, |
- Label* on_failure) { |
- uc16 char_mask; |
- if (one_byte) { |
- char_mask = String::kMaxOneByteCharCode; |
- } else { |
- char_mask = String::kMaxUtf16CodeUnit; |
- } |
- uc16 exor = c1 ^ c2; |
- // Check whether exor has only one bit set. |
- if (((exor - 1) & exor) == 0) { |
- // If c1 and c2 differ only by one bit. |
- // Ecma262UnCanonicalize always gives the highest number last. |
- DCHECK(c2 > c1); |
- uc16 mask = char_mask ^ exor; |
- macro_assembler->CheckNotCharacterAfterAnd(c1, mask, on_failure); |
- return true; |
- } |
- DCHECK(c2 > c1); |
- uc16 diff = c2 - c1; |
- if (((diff - 1) & diff) == 0 && c1 >= diff) { |
- // If the characters differ by 2^n but don't differ by one bit then |
- // subtract the difference from the found character, then do the or |
- // trick. We avoid the theoretical case where negative numbers are |
- // involved in order to simplify code generation. |
- uc16 mask = char_mask ^ diff; |
- macro_assembler->CheckNotCharacterAfterMinusAnd(c1 - diff, |
- diff, |
- mask, |
- on_failure); |
- return true; |
- } |
- return false; |
-} |
- |
- |
-typedef bool EmitCharacterFunction(Isolate* isolate, |
- RegExpCompiler* compiler, |
- uc16 c, |
- Label* on_failure, |
- int cp_offset, |
- bool check, |
- bool preloaded); |
- |
-// Only emits letters (things that have case). Only used for case independent |
-// matches. |
-static inline bool EmitAtomLetter(Isolate* isolate, |
- RegExpCompiler* compiler, |
- uc16 c, |
- Label* on_failure, |
- int cp_offset, |
- bool check, |
- bool preloaded) { |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- bool one_byte = compiler->one_byte(); |
- unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- int length = GetCaseIndependentLetters(isolate, c, one_byte, chars); |
- if (length <= 1) return false; |
- // We may not need to check against the end of the input string |
- // if this character lies before a character that matched. |
- if (!preloaded) { |
- macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check); |
- } |
- Label ok; |
- DCHECK(unibrow::Ecma262UnCanonicalize::kMaxWidth == 4); |
- switch (length) { |
- case 2: { |
- if (ShortCutEmitCharacterPair(macro_assembler, one_byte, chars[0], |
- chars[1], on_failure)) { |
- } else { |
- macro_assembler->CheckCharacter(chars[0], &ok); |
- macro_assembler->CheckNotCharacter(chars[1], on_failure); |
- macro_assembler->Bind(&ok); |
- } |
- break; |
- } |
- case 4: |
- macro_assembler->CheckCharacter(chars[3], &ok); |
- // Fall through! |
- case 3: |
- macro_assembler->CheckCharacter(chars[0], &ok); |
- macro_assembler->CheckCharacter(chars[1], &ok); |
- macro_assembler->CheckNotCharacter(chars[2], on_failure); |
- macro_assembler->Bind(&ok); |
- break; |
- default: |
- UNREACHABLE(); |
- break; |
- } |
- return true; |
-} |
- |
- |
-static void EmitBoundaryTest(RegExpMacroAssembler* masm, |
- int border, |
- Label* fall_through, |
- Label* above_or_equal, |
- Label* below) { |
- if (below != fall_through) { |
- masm->CheckCharacterLT(border, below); |
- if (above_or_equal != fall_through) masm->GoTo(above_or_equal); |
- } else { |
- masm->CheckCharacterGT(border - 1, above_or_equal); |
- } |
-} |
- |
- |
-static void EmitDoubleBoundaryTest(RegExpMacroAssembler* masm, |
- int first, |
- int last, |
- Label* fall_through, |
- Label* in_range, |
- Label* out_of_range) { |
- if (in_range == fall_through) { |
- if (first == last) { |
- masm->CheckNotCharacter(first, out_of_range); |
- } else { |
- masm->CheckCharacterNotInRange(first, last, out_of_range); |
- } |
- } else { |
- if (first == last) { |
- masm->CheckCharacter(first, in_range); |
- } else { |
- masm->CheckCharacterInRange(first, last, in_range); |
- } |
- if (out_of_range != fall_through) masm->GoTo(out_of_range); |
- } |
-} |
- |
- |
-// even_label is for ranges[i] to ranges[i + 1] where i - start_index is even. |
-// odd_label is for ranges[i] to ranges[i + 1] where i - start_index is odd. |
-static void EmitUseLookupTable( |
- RegExpMacroAssembler* masm, |
- ZoneList<int>* ranges, |
- int start_index, |
- int end_index, |
- int min_char, |
- Label* fall_through, |
- Label* even_label, |
- Label* odd_label) { |
- static const int kSize = RegExpMacroAssembler::kTableSize; |
- static const int kMask = RegExpMacroAssembler::kTableMask; |
- |
- int base = (min_char & ~kMask); |
- USE(base); |
- |
- // Assert that everything is on one kTableSize page. |
- for (int i = start_index; i <= end_index; i++) { |
- DCHECK_EQ(ranges->at(i) & ~kMask, base); |
- } |
- DCHECK(start_index == 0 || (ranges->at(start_index - 1) & ~kMask) <= base); |
- |
- char templ[kSize]; |
- Label* on_bit_set; |
- Label* on_bit_clear; |
- int bit; |
- if (even_label == fall_through) { |
- on_bit_set = odd_label; |
- on_bit_clear = even_label; |
- bit = 1; |
- } else { |
- on_bit_set = even_label; |
- on_bit_clear = odd_label; |
- bit = 0; |
- } |
- for (int i = 0; i < (ranges->at(start_index) & kMask) && i < kSize; i++) { |
- templ[i] = bit; |
- } |
- int j = 0; |
- bit ^= 1; |
- for (int i = start_index; i < end_index; i++) { |
- for (j = (ranges->at(i) & kMask); j < (ranges->at(i + 1) & kMask); j++) { |
- templ[j] = bit; |
- } |
- bit ^= 1; |
- } |
- for (int i = j; i < kSize; i++) { |
- templ[i] = bit; |
- } |
- Factory* factory = masm->isolate()->factory(); |
- // TODO(erikcorry): Cache these. |
- Handle<ByteArray> ba = factory->NewByteArray(kSize, TENURED); |
- for (int i = 0; i < kSize; i++) { |
- ba->set(i, templ[i]); |
- } |
- masm->CheckBitInTable(ba, on_bit_set); |
- if (on_bit_clear != fall_through) masm->GoTo(on_bit_clear); |
-} |
- |
- |
-static void CutOutRange(RegExpMacroAssembler* masm, |
- ZoneList<int>* ranges, |
- int start_index, |
- int end_index, |
- int cut_index, |
- Label* even_label, |
- Label* odd_label) { |
- bool odd = (((cut_index - start_index) & 1) == 1); |
- Label* in_range_label = odd ? odd_label : even_label; |
- Label dummy; |
- EmitDoubleBoundaryTest(masm, |
- ranges->at(cut_index), |
- ranges->at(cut_index + 1) - 1, |
- &dummy, |
- in_range_label, |
- &dummy); |
- DCHECK(!dummy.is_linked()); |
- // Cut out the single range by rewriting the array. This creates a new |
- // range that is a merger of the two ranges on either side of the one we |
- // are cutting out. The oddity of the labels is preserved. |
- for (int j = cut_index; j > start_index; j--) { |
- ranges->at(j) = ranges->at(j - 1); |
- } |
- for (int j = cut_index + 1; j < end_index; j++) { |
- ranges->at(j) = ranges->at(j + 1); |
- } |
-} |
- |
- |
-// Unicode case. Split the search space into kSize spaces that are handled |
-// with recursion. |
-static void SplitSearchSpace(ZoneList<int>* ranges, |
- int start_index, |
- int end_index, |
- int* new_start_index, |
- int* new_end_index, |
- int* border) { |
- static const int kSize = RegExpMacroAssembler::kTableSize; |
- static const int kMask = RegExpMacroAssembler::kTableMask; |
- |
- int first = ranges->at(start_index); |
- int last = ranges->at(end_index) - 1; |
- |
- *new_start_index = start_index; |
- *border = (ranges->at(start_index) & ~kMask) + kSize; |
- while (*new_start_index < end_index) { |
- if (ranges->at(*new_start_index) > *border) break; |
- (*new_start_index)++; |
- } |
- // new_start_index is the index of the first edge that is beyond the |
- // current kSize space. |
- |
- // For very large search spaces we do a binary chop search of the non-Latin1 |
- // space instead of just going to the end of the current kSize space. The |
- // heuristics are complicated a little by the fact that any 128-character |
- // encoding space can be quickly tested with a table lookup, so we don't |
- // wish to do binary chop search at a smaller granularity than that. A |
- // 128-character space can take up a lot of space in the ranges array if, |
- // for example, we only want to match every second character (eg. the lower |
- // case characters on some Unicode pages). |
- int binary_chop_index = (end_index + start_index) / 2; |
- // The first test ensures that we get to the code that handles the Latin1 |
- // range with a single not-taken branch, speeding up this important |
- // character range (even non-Latin1 charset-based text has spaces and |
- // punctuation). |
- if (*border - 1 > String::kMaxOneByteCharCode && // Latin1 case. |
- end_index - start_index > (*new_start_index - start_index) * 2 && |
- last - first > kSize * 2 && binary_chop_index > *new_start_index && |
- ranges->at(binary_chop_index) >= first + 2 * kSize) { |
- int scan_forward_for_section_border = binary_chop_index;; |
- int new_border = (ranges->at(binary_chop_index) | kMask) + 1; |
- |
- while (scan_forward_for_section_border < end_index) { |
- if (ranges->at(scan_forward_for_section_border) > new_border) { |
- *new_start_index = scan_forward_for_section_border; |
- *border = new_border; |
- break; |
- } |
- scan_forward_for_section_border++; |
- } |
- } |
- |
- DCHECK(*new_start_index > start_index); |
- *new_end_index = *new_start_index - 1; |
- if (ranges->at(*new_end_index) == *border) { |
- (*new_end_index)--; |
- } |
- if (*border >= ranges->at(end_index)) { |
- *border = ranges->at(end_index); |
- *new_start_index = end_index; // Won't be used. |
- *new_end_index = end_index - 1; |
- } |
-} |
- |
- |
-// Gets a series of segment boundaries representing a character class. If the |
-// character is in the range between an even and an odd boundary (counting from |
-// start_index) then go to even_label, otherwise go to odd_label. We already |
-// know that the character is in the range of min_char to max_char inclusive. |
-// Either label can be NULL indicating backtracking. Either label can also be |
-// equal to the fall_through label. |
-static void GenerateBranches(RegExpMacroAssembler* masm, |
- ZoneList<int>* ranges, |
- int start_index, |
- int end_index, |
- uc16 min_char, |
- uc16 max_char, |
- Label* fall_through, |
- Label* even_label, |
- Label* odd_label) { |
- int first = ranges->at(start_index); |
- int last = ranges->at(end_index) - 1; |
- |
- DCHECK_LT(min_char, first); |
- |
- // Just need to test if the character is before or on-or-after |
- // a particular character. |
- if (start_index == end_index) { |
- EmitBoundaryTest(masm, first, fall_through, even_label, odd_label); |
- return; |
- } |
- |
- // Another almost trivial case: There is one interval in the middle that is |
- // different from the end intervals. |
- if (start_index + 1 == end_index) { |
- EmitDoubleBoundaryTest( |
- masm, first, last, fall_through, even_label, odd_label); |
- return; |
- } |
- |
- // It's not worth using table lookup if there are very few intervals in the |
- // character class. |
- if (end_index - start_index <= 6) { |
- // It is faster to test for individual characters, so we look for those |
- // first, then try arbitrary ranges in the second round. |
- static int kNoCutIndex = -1; |
- int cut = kNoCutIndex; |
- for (int i = start_index; i < end_index; i++) { |
- if (ranges->at(i) == ranges->at(i + 1) - 1) { |
- cut = i; |
- break; |
- } |
- } |
- if (cut == kNoCutIndex) cut = start_index; |
- CutOutRange( |
- masm, ranges, start_index, end_index, cut, even_label, odd_label); |
- DCHECK_GE(end_index - start_index, 2); |
- GenerateBranches(masm, |
- ranges, |
- start_index + 1, |
- end_index - 1, |
- min_char, |
- max_char, |
- fall_through, |
- even_label, |
- odd_label); |
- return; |
- } |
- |
- // If there are a lot of intervals in the regexp, then we will use tables to |
- // determine whether the character is inside or outside the character class. |
- static const int kBits = RegExpMacroAssembler::kTableSizeBits; |
- |
- if ((max_char >> kBits) == (min_char >> kBits)) { |
- EmitUseLookupTable(masm, |
- ranges, |
- start_index, |
- end_index, |
- min_char, |
- fall_through, |
- even_label, |
- odd_label); |
- return; |
- } |
- |
- if ((min_char >> kBits) != (first >> kBits)) { |
- masm->CheckCharacterLT(first, odd_label); |
- GenerateBranches(masm, |
- ranges, |
- start_index + 1, |
- end_index, |
- first, |
- max_char, |
- fall_through, |
- odd_label, |
- even_label); |
- return; |
- } |
- |
- int new_start_index = 0; |
- int new_end_index = 0; |
- int border = 0; |
- |
- SplitSearchSpace(ranges, |
- start_index, |
- end_index, |
- &new_start_index, |
- &new_end_index, |
- &border); |
- |
- Label handle_rest; |
- Label* above = &handle_rest; |
- if (border == last + 1) { |
- // We didn't find any section that started after the limit, so everything |
- // above the border is one of the terminal labels. |
- above = (end_index & 1) != (start_index & 1) ? odd_label : even_label; |
- DCHECK(new_end_index == end_index - 1); |
- } |
- |
- DCHECK_LE(start_index, new_end_index); |
- DCHECK_LE(new_start_index, end_index); |
- DCHECK_LT(start_index, new_start_index); |
- DCHECK_LT(new_end_index, end_index); |
- DCHECK(new_end_index + 1 == new_start_index || |
- (new_end_index + 2 == new_start_index && |
- border == ranges->at(new_end_index + 1))); |
- DCHECK_LT(min_char, border - 1); |
- DCHECK_LT(border, max_char); |
- DCHECK_LT(ranges->at(new_end_index), border); |
- DCHECK(border < ranges->at(new_start_index) || |
- (border == ranges->at(new_start_index) && |
- new_start_index == end_index && |
- new_end_index == end_index - 1 && |
- border == last + 1)); |
- DCHECK(new_start_index == 0 || border >= ranges->at(new_start_index - 1)); |
- |
- masm->CheckCharacterGT(border - 1, above); |
- Label dummy; |
- GenerateBranches(masm, |
- ranges, |
- start_index, |
- new_end_index, |
- min_char, |
- border - 1, |
- &dummy, |
- even_label, |
- odd_label); |
- if (handle_rest.is_linked()) { |
- masm->Bind(&handle_rest); |
- bool flip = (new_start_index & 1) != (start_index & 1); |
- GenerateBranches(masm, |
- ranges, |
- new_start_index, |
- end_index, |
- border, |
- max_char, |
- &dummy, |
- flip ? odd_label : even_label, |
- flip ? even_label : odd_label); |
- } |
-} |
- |
- |
-static void EmitCharClass(RegExpMacroAssembler* macro_assembler, |
- RegExpCharacterClass* cc, bool one_byte, |
- Label* on_failure, int cp_offset, bool check_offset, |
- bool preloaded, Zone* zone) { |
- ZoneList<CharacterRange>* ranges = cc->ranges(zone); |
- if (!CharacterRange::IsCanonical(ranges)) { |
- CharacterRange::Canonicalize(ranges); |
- } |
- |
- int max_char; |
- if (one_byte) { |
- max_char = String::kMaxOneByteCharCode; |
- } else { |
- max_char = String::kMaxUtf16CodeUnit; |
- } |
- |
- int range_count = ranges->length(); |
- |
- int last_valid_range = range_count - 1; |
- while (last_valid_range >= 0) { |
- CharacterRange& range = ranges->at(last_valid_range); |
- if (range.from() <= max_char) { |
- break; |
- } |
- last_valid_range--; |
- } |
- |
- if (last_valid_range < 0) { |
- if (!cc->is_negated()) { |
- macro_assembler->GoTo(on_failure); |
- } |
- if (check_offset) { |
- macro_assembler->CheckPosition(cp_offset, on_failure); |
- } |
- return; |
- } |
- |
- if (last_valid_range == 0 && |
- ranges->at(0).IsEverything(max_char)) { |
- if (cc->is_negated()) { |
- macro_assembler->GoTo(on_failure); |
- } else { |
- // This is a common case hit by non-anchored expressions. |
- if (check_offset) { |
- macro_assembler->CheckPosition(cp_offset, on_failure); |
- } |
- } |
- return; |
- } |
- if (last_valid_range == 0 && |
- !cc->is_negated() && |
- ranges->at(0).IsEverything(max_char)) { |
- // This is a common case hit by non-anchored expressions. |
- if (check_offset) { |
- macro_assembler->CheckPosition(cp_offset, on_failure); |
- } |
- return; |
- } |
- |
- if (!preloaded) { |
- macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check_offset); |
- } |
- |
- if (cc->is_standard(zone) && |
- macro_assembler->CheckSpecialCharacterClass(cc->standard_type(), |
- on_failure)) { |
- return; |
- } |
- |
- |
- // A new list with ascending entries. Each entry is a code unit |
- // where there is a boundary between code units that are part of |
- // the class and code units that are not. Normally we insert an |
- // entry at zero which goes to the failure label, but if there |
- // was already one there we fall through for success on that entry. |
- // Subsequent entries have alternating meaning (success/failure). |
- ZoneList<int>* range_boundaries = |
- new(zone) ZoneList<int>(last_valid_range, zone); |
- |
- bool zeroth_entry_is_failure = !cc->is_negated(); |
- |
- for (int i = 0; i <= last_valid_range; i++) { |
- CharacterRange& range = ranges->at(i); |
- if (range.from() == 0) { |
- DCHECK_EQ(i, 0); |
- zeroth_entry_is_failure = !zeroth_entry_is_failure; |
- } else { |
- range_boundaries->Add(range.from(), zone); |
- } |
- range_boundaries->Add(range.to() + 1, zone); |
- } |
- int end_index = range_boundaries->length() - 1; |
- if (range_boundaries->at(end_index) > max_char) { |
- end_index--; |
- } |
- |
- Label fall_through; |
- GenerateBranches(macro_assembler, |
- range_boundaries, |
- 0, // start_index. |
- end_index, |
- 0, // min_char. |
- max_char, |
- &fall_through, |
- zeroth_entry_is_failure ? &fall_through : on_failure, |
- zeroth_entry_is_failure ? on_failure : &fall_through); |
- macro_assembler->Bind(&fall_through); |
-} |
- |
- |
-RegExpNode::~RegExpNode() { |
-} |
- |
- |
-RegExpNode::LimitResult RegExpNode::LimitVersions(RegExpCompiler* compiler, |
- Trace* trace) { |
- // If we are generating a greedy loop then don't stop and don't reuse code. |
- if (trace->stop_node() != NULL) { |
- return CONTINUE; |
- } |
- |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- if (trace->is_trivial()) { |
- if (label_.is_bound() || on_work_list() || !KeepRecursing(compiler)) { |
- // If a generic version is already scheduled to be generated or we have |
- // recursed too deeply then just generate a jump to that code. |
- macro_assembler->GoTo(&label_); |
- // This will queue it up for generation of a generic version if it hasn't |
- // already been queued. |
- compiler->AddWork(this); |
- return DONE; |
- } |
- // Generate generic version of the node and bind the label for later use. |
- macro_assembler->Bind(&label_); |
- return CONTINUE; |
- } |
- |
- // We are being asked to make a non-generic version. Keep track of how many |
- // non-generic versions we generate so as not to overdo it. |
- trace_count_++; |
- if (KeepRecursing(compiler) && compiler->optimize() && |
- trace_count_ < kMaxCopiesCodeGenerated) { |
- return CONTINUE; |
- } |
- |
- // If we get here code has been generated for this node too many times or |
- // recursion is too deep. Time to switch to a generic version. The code for |
- // generic versions above can handle deep recursion properly. |
- bool was_limiting = compiler->limiting_recursion(); |
- compiler->set_limiting_recursion(true); |
- trace->Flush(compiler, this); |
- compiler->set_limiting_recursion(was_limiting); |
- return DONE; |
-} |
- |
- |
-bool RegExpNode::KeepRecursing(RegExpCompiler* compiler) { |
- return !compiler->limiting_recursion() && |
- compiler->recursion_depth() <= RegExpCompiler::kMaxRecursion; |
-} |
- |
- |
-int ActionNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- if (budget <= 0) return 0; |
- if (action_type_ == POSITIVE_SUBMATCH_SUCCESS) return 0; // Rewinds input! |
- return on_success()->EatsAtLeast(still_to_find, |
- budget - 1, |
- not_at_start); |
-} |
- |
- |
-void ActionNode::FillInBMInfo(Isolate* isolate, int offset, int budget, |
- BoyerMooreLookahead* bm, bool not_at_start) { |
- if (action_type_ == BEGIN_SUBMATCH) { |
- bm->SetRest(offset); |
- } else if (action_type_ != POSITIVE_SUBMATCH_SUCCESS) { |
- on_success()->FillInBMInfo(isolate, offset, budget - 1, bm, not_at_start); |
- } |
- SaveBMInfo(bm, not_at_start, offset); |
-} |
- |
- |
-int AssertionNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- if (budget <= 0) return 0; |
- // If we know we are not at the start and we are asked "how many characters |
- // will you match if you succeed?" then we can answer anything since false |
- // implies false. So lets just return the max answer (still_to_find) since |
- // that won't prevent us from preloading a lot of characters for the other |
- // branches in the node graph. |
- if (assertion_type() == AT_START && not_at_start) return still_to_find; |
- return on_success()->EatsAtLeast(still_to_find, |
- budget - 1, |
- not_at_start); |
-} |
- |
- |
-void AssertionNode::FillInBMInfo(Isolate* isolate, int offset, int budget, |
- BoyerMooreLookahead* bm, bool not_at_start) { |
- // Match the behaviour of EatsAtLeast on this node. |
- if (assertion_type() == AT_START && not_at_start) return; |
- on_success()->FillInBMInfo(isolate, offset, budget - 1, bm, not_at_start); |
- SaveBMInfo(bm, not_at_start, offset); |
-} |
- |
- |
-int BackReferenceNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- if (budget <= 0) return 0; |
- return on_success()->EatsAtLeast(still_to_find, |
- budget - 1, |
- not_at_start); |
-} |
- |
- |
-int TextNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- int answer = Length(); |
- if (answer >= still_to_find) return answer; |
- if (budget <= 0) return answer; |
- // We are not at start after this node so we set the last argument to 'true'. |
- return answer + on_success()->EatsAtLeast(still_to_find - answer, |
- budget - 1, |
- true); |
-} |
- |
- |
-int NegativeLookaheadChoiceNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- if (budget <= 0) return 0; |
- // Alternative 0 is the negative lookahead, alternative 1 is what comes |
- // afterwards. |
- RegExpNode* node = alternatives_->at(1).node(); |
- return node->EatsAtLeast(still_to_find, budget - 1, not_at_start); |
-} |
- |
- |
-void NegativeLookaheadChoiceNode::GetQuickCheckDetails( |
- QuickCheckDetails* details, |
- RegExpCompiler* compiler, |
- int filled_in, |
- bool not_at_start) { |
- // Alternative 0 is the negative lookahead, alternative 1 is what comes |
- // afterwards. |
- RegExpNode* node = alternatives_->at(1).node(); |
- return node->GetQuickCheckDetails(details, compiler, filled_in, not_at_start); |
-} |
- |
- |
-int ChoiceNode::EatsAtLeastHelper(int still_to_find, |
- int budget, |
- RegExpNode* ignore_this_node, |
- bool not_at_start) { |
- if (budget <= 0) return 0; |
- int min = 100; |
- int choice_count = alternatives_->length(); |
- budget = (budget - 1) / choice_count; |
- for (int i = 0; i < choice_count; i++) { |
- RegExpNode* node = alternatives_->at(i).node(); |
- if (node == ignore_this_node) continue; |
- int node_eats_at_least = |
- node->EatsAtLeast(still_to_find, budget, not_at_start); |
- if (node_eats_at_least < min) min = node_eats_at_least; |
- if (min == 0) return 0; |
- } |
- return min; |
-} |
- |
- |
-int LoopChoiceNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- return EatsAtLeastHelper(still_to_find, |
- budget - 1, |
- loop_node_, |
- not_at_start); |
-} |
- |
- |
-int ChoiceNode::EatsAtLeast(int still_to_find, |
- int budget, |
- bool not_at_start) { |
- return EatsAtLeastHelper(still_to_find, |
- budget, |
- NULL, |
- not_at_start); |
-} |
- |
- |
-// Takes the left-most 1-bit and smears it out, setting all bits to its right. |
-static inline uint32_t SmearBitsRight(uint32_t v) { |
- v |= v >> 1; |
- v |= v >> 2; |
- v |= v >> 4; |
- v |= v >> 8; |
- v |= v >> 16; |
- return v; |
-} |
- |
- |
-bool QuickCheckDetails::Rationalize(bool asc) { |
- bool found_useful_op = false; |
- uint32_t char_mask; |
- if (asc) { |
- char_mask = String::kMaxOneByteCharCode; |
- } else { |
- char_mask = String::kMaxUtf16CodeUnit; |
- } |
- mask_ = 0; |
- value_ = 0; |
- int char_shift = 0; |
- for (int i = 0; i < characters_; i++) { |
- Position* pos = &positions_[i]; |
- if ((pos->mask & String::kMaxOneByteCharCode) != 0) { |
- found_useful_op = true; |
- } |
- mask_ |= (pos->mask & char_mask) << char_shift; |
- value_ |= (pos->value & char_mask) << char_shift; |
- char_shift += asc ? 8 : 16; |
- } |
- return found_useful_op; |
-} |
- |
- |
-bool RegExpNode::EmitQuickCheck(RegExpCompiler* compiler, |
- Trace* bounds_check_trace, |
- Trace* trace, |
- bool preload_has_checked_bounds, |
- Label* on_possible_success, |
- QuickCheckDetails* details, |
- bool fall_through_on_failure) { |
- if (details->characters() == 0) return false; |
- GetQuickCheckDetails( |
- details, compiler, 0, trace->at_start() == Trace::FALSE_VALUE); |
- if (details->cannot_match()) return false; |
- if (!details->Rationalize(compiler->one_byte())) return false; |
- DCHECK(details->characters() == 1 || |
- compiler->macro_assembler()->CanReadUnaligned()); |
- uint32_t mask = details->mask(); |
- uint32_t value = details->value(); |
- |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- |
- if (trace->characters_preloaded() != details->characters()) { |
- DCHECK(trace->cp_offset() == bounds_check_trace->cp_offset()); |
- // We are attempting to preload the minimum number of characters |
- // any choice would eat, so if the bounds check fails, then none of the |
- // choices can succeed, so we can just immediately backtrack, rather |
- // than go to the next choice. |
- assembler->LoadCurrentCharacter(trace->cp_offset(), |
- bounds_check_trace->backtrack(), |
- !preload_has_checked_bounds, |
- details->characters()); |
- } |
- |
- |
- bool need_mask = true; |
- |
- if (details->characters() == 1) { |
- // If number of characters preloaded is 1 then we used a byte or 16 bit |
- // load so the value is already masked down. |
- uint32_t char_mask; |
- if (compiler->one_byte()) { |
- char_mask = String::kMaxOneByteCharCode; |
- } else { |
- char_mask = String::kMaxUtf16CodeUnit; |
- } |
- if ((mask & char_mask) == char_mask) need_mask = false; |
- mask &= char_mask; |
- } else { |
- // For 2-character preloads in one-byte mode or 1-character preloads in |
- // two-byte mode we also use a 16 bit load with zero extend. |
- if (details->characters() == 2 && compiler->one_byte()) { |
- if ((mask & 0xffff) == 0xffff) need_mask = false; |
- } else if (details->characters() == 1 && !compiler->one_byte()) { |
- if ((mask & 0xffff) == 0xffff) need_mask = false; |
- } else { |
- if (mask == 0xffffffff) need_mask = false; |
- } |
- } |
- |
- if (fall_through_on_failure) { |
- if (need_mask) { |
- assembler->CheckCharacterAfterAnd(value, mask, on_possible_success); |
- } else { |
- assembler->CheckCharacter(value, on_possible_success); |
- } |
- } else { |
- if (need_mask) { |
- assembler->CheckNotCharacterAfterAnd(value, mask, trace->backtrack()); |
- } else { |
- assembler->CheckNotCharacter(value, trace->backtrack()); |
- } |
- } |
- return true; |
-} |
- |
- |
-// Here is the meat of GetQuickCheckDetails (see also the comment on the |
-// super-class in the .h file). |
-// |
-// We iterate along the text object, building up for each character a |
-// mask and value that can be used to test for a quick failure to match. |
-// The masks and values for the positions will be combined into a single |
-// machine word for the current character width in order to be used in |
-// generating a quick check. |
-void TextNode::GetQuickCheckDetails(QuickCheckDetails* details, |
- RegExpCompiler* compiler, |
- int characters_filled_in, |
- bool not_at_start) { |
- Isolate* isolate = compiler->macro_assembler()->isolate(); |
- DCHECK(characters_filled_in < details->characters()); |
- int characters = details->characters(); |
- int char_mask; |
- if (compiler->one_byte()) { |
- char_mask = String::kMaxOneByteCharCode; |
- } else { |
- char_mask = String::kMaxUtf16CodeUnit; |
- } |
- for (int k = 0; k < elms_->length(); k++) { |
- TextElement elm = elms_->at(k); |
- if (elm.text_type() == TextElement::ATOM) { |
- Vector<const uc16> quarks = elm.atom()->data(); |
- for (int i = 0; i < characters && i < quarks.length(); i++) { |
- QuickCheckDetails::Position* pos = |
- details->positions(characters_filled_in); |
- uc16 c = quarks[i]; |
- if (compiler->ignore_case()) { |
- unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- int length = GetCaseIndependentLetters(isolate, c, |
- compiler->one_byte(), chars); |
- if (length == 0) { |
- // This can happen because all case variants are non-Latin1, but we |
- // know the input is Latin1. |
- details->set_cannot_match(); |
- pos->determines_perfectly = false; |
- return; |
- } |
- if (length == 1) { |
- // This letter has no case equivalents, so it's nice and simple |
- // and the mask-compare will determine definitely whether we have |
- // a match at this character position. |
- pos->mask = char_mask; |
- pos->value = c; |
- pos->determines_perfectly = true; |
- } else { |
- uint32_t common_bits = char_mask; |
- uint32_t bits = chars[0]; |
- for (int j = 1; j < length; j++) { |
- uint32_t differing_bits = ((chars[j] & common_bits) ^ bits); |
- common_bits ^= differing_bits; |
- bits &= common_bits; |
- } |
- // If length is 2 and common bits has only one zero in it then |
- // our mask and compare instruction will determine definitely |
- // whether we have a match at this character position. Otherwise |
- // it can only be an approximate check. |
- uint32_t one_zero = (common_bits | ~char_mask); |
- if (length == 2 && ((~one_zero) & ((~one_zero) - 1)) == 0) { |
- pos->determines_perfectly = true; |
- } |
- pos->mask = common_bits; |
- pos->value = bits; |
- } |
- } else { |
- // Don't ignore case. Nice simple case where the mask-compare will |
- // determine definitely whether we have a match at this character |
- // position. |
- if (c > char_mask) { |
- details->set_cannot_match(); |
- pos->determines_perfectly = false; |
- return; |
- } |
- pos->mask = char_mask; |
- pos->value = c; |
- pos->determines_perfectly = true; |
- } |
- characters_filled_in++; |
- DCHECK(characters_filled_in <= details->characters()); |
- if (characters_filled_in == details->characters()) { |
- return; |
- } |
- } |
- } else { |
- QuickCheckDetails::Position* pos = |
- details->positions(characters_filled_in); |
- RegExpCharacterClass* tree = elm.char_class(); |
- ZoneList<CharacterRange>* ranges = tree->ranges(zone()); |
- if (tree->is_negated()) { |
- // A quick check uses multi-character mask and compare. There is no |
- // useful way to incorporate a negative char class into this scheme |
- // so we just conservatively create a mask and value that will always |
- // succeed. |
- pos->mask = 0; |
- pos->value = 0; |
- } else { |
- int first_range = 0; |
- while (ranges->at(first_range).from() > char_mask) { |
- first_range++; |
- if (first_range == ranges->length()) { |
- details->set_cannot_match(); |
- pos->determines_perfectly = false; |
- return; |
- } |
- } |
- CharacterRange range = ranges->at(first_range); |
- uc16 from = range.from(); |
- uc16 to = range.to(); |
- if (to > char_mask) { |
- to = char_mask; |
- } |
- uint32_t differing_bits = (from ^ to); |
- // A mask and compare is only perfect if the differing bits form a |
- // number like 00011111 with one single block of trailing 1s. |
- if ((differing_bits & (differing_bits + 1)) == 0 && |
- from + differing_bits == to) { |
- pos->determines_perfectly = true; |
- } |
- uint32_t common_bits = ~SmearBitsRight(differing_bits); |
- uint32_t bits = (from & common_bits); |
- for (int i = first_range + 1; i < ranges->length(); i++) { |
- CharacterRange range = ranges->at(i); |
- uc16 from = range.from(); |
- uc16 to = range.to(); |
- if (from > char_mask) continue; |
- if (to > char_mask) to = char_mask; |
- // Here we are combining more ranges into the mask and compare |
- // value. With each new range the mask becomes more sparse and |
- // so the chances of a false positive rise. A character class |
- // with multiple ranges is assumed never to be equivalent to a |
- // mask and compare operation. |
- pos->determines_perfectly = false; |
- uint32_t new_common_bits = (from ^ to); |
- new_common_bits = ~SmearBitsRight(new_common_bits); |
- common_bits &= new_common_bits; |
- bits &= new_common_bits; |
- uint32_t differing_bits = (from & common_bits) ^ bits; |
- common_bits ^= differing_bits; |
- bits &= common_bits; |
- } |
- pos->mask = common_bits; |
- pos->value = bits; |
- } |
- characters_filled_in++; |
- DCHECK(characters_filled_in <= details->characters()); |
- if (characters_filled_in == details->characters()) { |
- return; |
- } |
- } |
- } |
- DCHECK(characters_filled_in != details->characters()); |
- if (!details->cannot_match()) { |
- on_success()-> GetQuickCheckDetails(details, |
- compiler, |
- characters_filled_in, |
- true); |
- } |
-} |
- |
- |
-void QuickCheckDetails::Clear() { |
- for (int i = 0; i < characters_; i++) { |
- positions_[i].mask = 0; |
- positions_[i].value = 0; |
- positions_[i].determines_perfectly = false; |
- } |
- characters_ = 0; |
-} |
- |
- |
-void QuickCheckDetails::Advance(int by, bool one_byte) { |
- DCHECK(by >= 0); |
- if (by >= characters_) { |
- Clear(); |
- return; |
- } |
- for (int i = 0; i < characters_ - by; i++) { |
- positions_[i] = positions_[by + i]; |
- } |
- for (int i = characters_ - by; i < characters_; i++) { |
- positions_[i].mask = 0; |
- positions_[i].value = 0; |
- positions_[i].determines_perfectly = false; |
- } |
- characters_ -= by; |
- // We could change mask_ and value_ here but we would never advance unless |
- // they had already been used in a check and they won't be used again because |
- // it would gain us nothing. So there's no point. |
-} |
- |
- |
-void QuickCheckDetails::Merge(QuickCheckDetails* other, int from_index) { |
- DCHECK(characters_ == other->characters_); |
- if (other->cannot_match_) { |
- return; |
- } |
- if (cannot_match_) { |
- *this = *other; |
- return; |
- } |
- for (int i = from_index; i < characters_; i++) { |
- QuickCheckDetails::Position* pos = positions(i); |
- QuickCheckDetails::Position* other_pos = other->positions(i); |
- if (pos->mask != other_pos->mask || |
- pos->value != other_pos->value || |
- !other_pos->determines_perfectly) { |
- // Our mask-compare operation will be approximate unless we have the |
- // exact same operation on both sides of the alternation. |
- pos->determines_perfectly = false; |
- } |
- pos->mask &= other_pos->mask; |
- pos->value &= pos->mask; |
- other_pos->value &= pos->mask; |
- uc16 differing_bits = (pos->value ^ other_pos->value); |
- pos->mask &= ~differing_bits; |
- pos->value &= pos->mask; |
- } |
-} |
- |
- |
-class VisitMarker { |
- public: |
- explicit VisitMarker(NodeInfo* info) : info_(info) { |
- DCHECK(!info->visited); |
- info->visited = true; |
- } |
- ~VisitMarker() { |
- info_->visited = false; |
- } |
- private: |
- NodeInfo* info_; |
-}; |
- |
- |
-RegExpNode* SeqRegExpNode::FilterOneByte(int depth, bool ignore_case) { |
- if (info()->replacement_calculated) return replacement(); |
- if (depth < 0) return this; |
- DCHECK(!info()->visited); |
- VisitMarker marker(info()); |
- return FilterSuccessor(depth - 1, ignore_case); |
-} |
- |
- |
-RegExpNode* SeqRegExpNode::FilterSuccessor(int depth, bool ignore_case) { |
- RegExpNode* next = on_success_->FilterOneByte(depth - 1, ignore_case); |
- if (next == NULL) return set_replacement(NULL); |
- on_success_ = next; |
- return set_replacement(this); |
-} |
- |
- |
-// We need to check for the following characters: 0x39c 0x3bc 0x178. |
-static inline bool RangeContainsLatin1Equivalents(CharacterRange range) { |
- // TODO(dcarney): this could be a lot more efficient. |
- return range.Contains(0x39c) || |
- range.Contains(0x3bc) || range.Contains(0x178); |
-} |
- |
- |
-static bool RangesContainLatin1Equivalents(ZoneList<CharacterRange>* ranges) { |
- for (int i = 0; i < ranges->length(); i++) { |
- // TODO(dcarney): this could be a lot more efficient. |
- if (RangeContainsLatin1Equivalents(ranges->at(i))) return true; |
- } |
- return false; |
-} |
- |
- |
-RegExpNode* TextNode::FilterOneByte(int depth, bool ignore_case) { |
- if (info()->replacement_calculated) return replacement(); |
- if (depth < 0) return this; |
- DCHECK(!info()->visited); |
- VisitMarker marker(info()); |
- int element_count = elms_->length(); |
- for (int i = 0; i < element_count; i++) { |
- TextElement elm = elms_->at(i); |
- if (elm.text_type() == TextElement::ATOM) { |
- Vector<const uc16> quarks = elm.atom()->data(); |
- for (int j = 0; j < quarks.length(); j++) { |
- uint16_t c = quarks[j]; |
- if (c <= String::kMaxOneByteCharCode) continue; |
- if (!ignore_case) return set_replacement(NULL); |
- // Here, we need to check for characters whose upper and lower cases |
- // are outside the Latin-1 range. |
- uint16_t converted = unibrow::Latin1::ConvertNonLatin1ToLatin1(c); |
- // Character is outside Latin-1 completely |
- if (converted == 0) return set_replacement(NULL); |
- // Convert quark to Latin-1 in place. |
- uint16_t* copy = const_cast<uint16_t*>(quarks.start()); |
- copy[j] = converted; |
- } |
- } else { |
- DCHECK(elm.text_type() == TextElement::CHAR_CLASS); |
- RegExpCharacterClass* cc = elm.char_class(); |
- ZoneList<CharacterRange>* ranges = cc->ranges(zone()); |
- if (!CharacterRange::IsCanonical(ranges)) { |
- CharacterRange::Canonicalize(ranges); |
- } |
- // Now they are in order so we only need to look at the first. |
- int range_count = ranges->length(); |
- if (cc->is_negated()) { |
- if (range_count != 0 && |
- ranges->at(0).from() == 0 && |
- ranges->at(0).to() >= String::kMaxOneByteCharCode) { |
- // This will be handled in a later filter. |
- if (ignore_case && RangesContainLatin1Equivalents(ranges)) continue; |
- return set_replacement(NULL); |
- } |
- } else { |
- if (range_count == 0 || |
- ranges->at(0).from() > String::kMaxOneByteCharCode) { |
- // This will be handled in a later filter. |
- if (ignore_case && RangesContainLatin1Equivalents(ranges)) continue; |
- return set_replacement(NULL); |
- } |
- } |
- } |
- } |
- return FilterSuccessor(depth - 1, ignore_case); |
-} |
- |
- |
-RegExpNode* LoopChoiceNode::FilterOneByte(int depth, bool ignore_case) { |
- if (info()->replacement_calculated) return replacement(); |
- if (depth < 0) return this; |
- if (info()->visited) return this; |
- { |
- VisitMarker marker(info()); |
- |
- RegExpNode* continue_replacement = |
- continue_node_->FilterOneByte(depth - 1, ignore_case); |
- // If we can't continue after the loop then there is no sense in doing the |
- // loop. |
- if (continue_replacement == NULL) return set_replacement(NULL); |
- } |
- |
- return ChoiceNode::FilterOneByte(depth - 1, ignore_case); |
-} |
- |
- |
-RegExpNode* ChoiceNode::FilterOneByte(int depth, bool ignore_case) { |
- if (info()->replacement_calculated) return replacement(); |
- if (depth < 0) return this; |
- if (info()->visited) return this; |
- VisitMarker marker(info()); |
- int choice_count = alternatives_->length(); |
- |
- for (int i = 0; i < choice_count; i++) { |
- GuardedAlternative alternative = alternatives_->at(i); |
- if (alternative.guards() != NULL && alternative.guards()->length() != 0) { |
- set_replacement(this); |
- return this; |
- } |
- } |
- |
- int surviving = 0; |
- RegExpNode* survivor = NULL; |
- for (int i = 0; i < choice_count; i++) { |
- GuardedAlternative alternative = alternatives_->at(i); |
- RegExpNode* replacement = |
- alternative.node()->FilterOneByte(depth - 1, ignore_case); |
- DCHECK(replacement != this); // No missing EMPTY_MATCH_CHECK. |
- if (replacement != NULL) { |
- alternatives_->at(i).set_node(replacement); |
- surviving++; |
- survivor = replacement; |
- } |
- } |
- if (surviving < 2) return set_replacement(survivor); |
- |
- set_replacement(this); |
- if (surviving == choice_count) { |
- return this; |
- } |
- // Only some of the nodes survived the filtering. We need to rebuild the |
- // alternatives list. |
- ZoneList<GuardedAlternative>* new_alternatives = |
- new(zone()) ZoneList<GuardedAlternative>(surviving, zone()); |
- for (int i = 0; i < choice_count; i++) { |
- RegExpNode* replacement = |
- alternatives_->at(i).node()->FilterOneByte(depth - 1, ignore_case); |
- if (replacement != NULL) { |
- alternatives_->at(i).set_node(replacement); |
- new_alternatives->Add(alternatives_->at(i), zone()); |
- } |
- } |
- alternatives_ = new_alternatives; |
- return this; |
-} |
- |
- |
-RegExpNode* NegativeLookaheadChoiceNode::FilterOneByte(int depth, |
- bool ignore_case) { |
- if (info()->replacement_calculated) return replacement(); |
- if (depth < 0) return this; |
- if (info()->visited) return this; |
- VisitMarker marker(info()); |
- // Alternative 0 is the negative lookahead, alternative 1 is what comes |
- // afterwards. |
- RegExpNode* node = alternatives_->at(1).node(); |
- RegExpNode* replacement = node->FilterOneByte(depth - 1, ignore_case); |
- if (replacement == NULL) return set_replacement(NULL); |
- alternatives_->at(1).set_node(replacement); |
- |
- RegExpNode* neg_node = alternatives_->at(0).node(); |
- RegExpNode* neg_replacement = neg_node->FilterOneByte(depth - 1, ignore_case); |
- // If the negative lookahead is always going to fail then |
- // we don't need to check it. |
- if (neg_replacement == NULL) return set_replacement(replacement); |
- alternatives_->at(0).set_node(neg_replacement); |
- return set_replacement(this); |
-} |
- |
- |
-void LoopChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details, |
- RegExpCompiler* compiler, |
- int characters_filled_in, |
- bool not_at_start) { |
- if (body_can_be_zero_length_ || info()->visited) return; |
- VisitMarker marker(info()); |
- return ChoiceNode::GetQuickCheckDetails(details, |
- compiler, |
- characters_filled_in, |
- not_at_start); |
-} |
- |
- |
-void LoopChoiceNode::FillInBMInfo(Isolate* isolate, int offset, int budget, |
- BoyerMooreLookahead* bm, bool not_at_start) { |
- if (body_can_be_zero_length_ || budget <= 0) { |
- bm->SetRest(offset); |
- SaveBMInfo(bm, not_at_start, offset); |
- return; |
- } |
- ChoiceNode::FillInBMInfo(isolate, offset, budget - 1, bm, not_at_start); |
- SaveBMInfo(bm, not_at_start, offset); |
-} |
- |
- |
-void ChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details, |
- RegExpCompiler* compiler, |
- int characters_filled_in, |
- bool not_at_start) { |
- not_at_start = (not_at_start || not_at_start_); |
- int choice_count = alternatives_->length(); |
- DCHECK(choice_count > 0); |
- alternatives_->at(0).node()->GetQuickCheckDetails(details, |
- compiler, |
- characters_filled_in, |
- not_at_start); |
- for (int i = 1; i < choice_count; i++) { |
- QuickCheckDetails new_details(details->characters()); |
- RegExpNode* node = alternatives_->at(i).node(); |
- node->GetQuickCheckDetails(&new_details, compiler, |
- characters_filled_in, |
- not_at_start); |
- // Here we merge the quick match details of the two branches. |
- details->Merge(&new_details, characters_filled_in); |
- } |
-} |
- |
- |
-// Check for [0-9A-Z_a-z]. |
-static void EmitWordCheck(RegExpMacroAssembler* assembler, |
- Label* word, |
- Label* non_word, |
- bool fall_through_on_word) { |
- if (assembler->CheckSpecialCharacterClass( |
- fall_through_on_word ? 'w' : 'W', |
- fall_through_on_word ? non_word : word)) { |
- // Optimized implementation available. |
- return; |
- } |
- assembler->CheckCharacterGT('z', non_word); |
- assembler->CheckCharacterLT('0', non_word); |
- assembler->CheckCharacterGT('a' - 1, word); |
- assembler->CheckCharacterLT('9' + 1, word); |
- assembler->CheckCharacterLT('A', non_word); |
- assembler->CheckCharacterLT('Z' + 1, word); |
- if (fall_through_on_word) { |
- assembler->CheckNotCharacter('_', non_word); |
- } else { |
- assembler->CheckCharacter('_', word); |
- } |
-} |
- |
- |
-// Emit the code to check for a ^ in multiline mode (1-character lookbehind |
-// that matches newline or the start of input). |
-static void EmitHat(RegExpCompiler* compiler, |
- RegExpNode* on_success, |
- Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- // We will be loading the previous character into the current character |
- // register. |
- Trace new_trace(*trace); |
- new_trace.InvalidateCurrentCharacter(); |
- |
- Label ok; |
- if (new_trace.cp_offset() == 0) { |
- // The start of input counts as a newline in this context, so skip to |
- // ok if we are at the start. |
- assembler->CheckAtStart(&ok); |
- } |
- // We already checked that we are not at the start of input so it must be |
- // OK to load the previous character. |
- assembler->LoadCurrentCharacter(new_trace.cp_offset() -1, |
- new_trace.backtrack(), |
- false); |
- if (!assembler->CheckSpecialCharacterClass('n', |
- new_trace.backtrack())) { |
- // Newline means \n, \r, 0x2028 or 0x2029. |
- if (!compiler->one_byte()) { |
- assembler->CheckCharacterAfterAnd(0x2028, 0xfffe, &ok); |
- } |
- assembler->CheckCharacter('\n', &ok); |
- assembler->CheckNotCharacter('\r', new_trace.backtrack()); |
- } |
- assembler->Bind(&ok); |
- on_success->Emit(compiler, &new_trace); |
-} |
- |
- |
-// Emit the code to handle \b and \B (word-boundary or non-word-boundary). |
-void AssertionNode::EmitBoundaryCheck(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- Isolate* isolate = assembler->isolate(); |
- Trace::TriBool next_is_word_character = Trace::UNKNOWN; |
- bool not_at_start = (trace->at_start() == Trace::FALSE_VALUE); |
- BoyerMooreLookahead* lookahead = bm_info(not_at_start); |
- if (lookahead == NULL) { |
- int eats_at_least = |
- Min(kMaxLookaheadForBoyerMoore, EatsAtLeast(kMaxLookaheadForBoyerMoore, |
- kRecursionBudget, |
- not_at_start)); |
- if (eats_at_least >= 1) { |
- BoyerMooreLookahead* bm = |
- new(zone()) BoyerMooreLookahead(eats_at_least, compiler, zone()); |
- FillInBMInfo(isolate, 0, kRecursionBudget, bm, not_at_start); |
- if (bm->at(0)->is_non_word()) |
- next_is_word_character = Trace::FALSE_VALUE; |
- if (bm->at(0)->is_word()) next_is_word_character = Trace::TRUE_VALUE; |
- } |
- } else { |
- if (lookahead->at(0)->is_non_word()) |
- next_is_word_character = Trace::FALSE_VALUE; |
- if (lookahead->at(0)->is_word()) |
- next_is_word_character = Trace::TRUE_VALUE; |
- } |
- bool at_boundary = (assertion_type_ == AssertionNode::AT_BOUNDARY); |
- if (next_is_word_character == Trace::UNKNOWN) { |
- Label before_non_word; |
- Label before_word; |
- if (trace->characters_preloaded() != 1) { |
- assembler->LoadCurrentCharacter(trace->cp_offset(), &before_non_word); |
- } |
- // Fall through on non-word. |
- EmitWordCheck(assembler, &before_word, &before_non_word, false); |
- // Next character is not a word character. |
- assembler->Bind(&before_non_word); |
- Label ok; |
- BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord); |
- assembler->GoTo(&ok); |
- |
- assembler->Bind(&before_word); |
- BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord); |
- assembler->Bind(&ok); |
- } else if (next_is_word_character == Trace::TRUE_VALUE) { |
- BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord); |
- } else { |
- DCHECK(next_is_word_character == Trace::FALSE_VALUE); |
- BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord); |
- } |
-} |
- |
- |
-void AssertionNode::BacktrackIfPrevious( |
- RegExpCompiler* compiler, |
- Trace* trace, |
- AssertionNode::IfPrevious backtrack_if_previous) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- Trace new_trace(*trace); |
- new_trace.InvalidateCurrentCharacter(); |
- |
- Label fall_through, dummy; |
- |
- Label* non_word = backtrack_if_previous == kIsNonWord ? |
- new_trace.backtrack() : |
- &fall_through; |
- Label* word = backtrack_if_previous == kIsNonWord ? |
- &fall_through : |
- new_trace.backtrack(); |
- |
- if (new_trace.cp_offset() == 0) { |
- // The start of input counts as a non-word character, so the question is |
- // decided if we are at the start. |
- assembler->CheckAtStart(non_word); |
- } |
- // We already checked that we are not at the start of input so it must be |
- // OK to load the previous character. |
- assembler->LoadCurrentCharacter(new_trace.cp_offset() - 1, &dummy, false); |
- EmitWordCheck(assembler, word, non_word, backtrack_if_previous == kIsNonWord); |
- |
- assembler->Bind(&fall_through); |
- on_success()->Emit(compiler, &new_trace); |
-} |
- |
- |
-void AssertionNode::GetQuickCheckDetails(QuickCheckDetails* details, |
- RegExpCompiler* compiler, |
- int filled_in, |
- bool not_at_start) { |
- if (assertion_type_ == AT_START && not_at_start) { |
- details->set_cannot_match(); |
- return; |
- } |
- return on_success()->GetQuickCheckDetails(details, |
- compiler, |
- filled_in, |
- not_at_start); |
-} |
- |
- |
-void AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- switch (assertion_type_) { |
- case AT_END: { |
- Label ok; |
- assembler->CheckPosition(trace->cp_offset(), &ok); |
- assembler->GoTo(trace->backtrack()); |
- assembler->Bind(&ok); |
- break; |
- } |
- case AT_START: { |
- if (trace->at_start() == Trace::FALSE_VALUE) { |
- assembler->GoTo(trace->backtrack()); |
- return; |
- } |
- if (trace->at_start() == Trace::UNKNOWN) { |
- assembler->CheckNotAtStart(trace->backtrack()); |
- Trace at_start_trace = *trace; |
- at_start_trace.set_at_start(true); |
- on_success()->Emit(compiler, &at_start_trace); |
- return; |
- } |
- } |
- break; |
- case AFTER_NEWLINE: |
- EmitHat(compiler, on_success(), trace); |
- return; |
- case AT_BOUNDARY: |
- case AT_NON_BOUNDARY: { |
- EmitBoundaryCheck(compiler, trace); |
- return; |
- } |
- } |
- on_success()->Emit(compiler, trace); |
-} |
- |
- |
-static bool DeterminedAlready(QuickCheckDetails* quick_check, int offset) { |
- if (quick_check == NULL) return false; |
- if (offset >= quick_check->characters()) return false; |
- return quick_check->positions(offset)->determines_perfectly; |
-} |
- |
- |
-static void UpdateBoundsCheck(int index, int* checked_up_to) { |
- if (index > *checked_up_to) { |
- *checked_up_to = index; |
- } |
-} |
- |
- |
-// We call this repeatedly to generate code for each pass over the text node. |
-// The passes are in increasing order of difficulty because we hope one |
-// of the first passes will fail in which case we are saved the work of the |
-// later passes. for example for the case independent regexp /%[asdfghjkl]a/ |
-// we will check the '%' in the first pass, the case independent 'a' in the |
-// second pass and the character class in the last pass. |
-// |
-// The passes are done from right to left, so for example to test for /bar/ |
-// we will first test for an 'r' with offset 2, then an 'a' with offset 1 |
-// and then a 'b' with offset 0. This means we can avoid the end-of-input |
-// bounds check most of the time. In the example we only need to check for |
-// end-of-input when loading the putative 'r'. |
-// |
-// A slight complication involves the fact that the first character may already |
-// be fetched into a register by the previous node. In this case we want to |
-// do the test for that character first. We do this in separate passes. The |
-// 'preloaded' argument indicates that we are doing such a 'pass'. If such a |
-// pass has been performed then subsequent passes will have true in |
-// first_element_checked to indicate that that character does not need to be |
-// checked again. |
-// |
-// In addition to all this we are passed a Trace, which can |
-// contain an AlternativeGeneration object. In this AlternativeGeneration |
-// object we can see details of any quick check that was already passed in |
-// order to get to the code we are now generating. The quick check can involve |
-// loading characters, which means we do not need to recheck the bounds |
-// up to the limit the quick check already checked. In addition the quick |
-// check can have involved a mask and compare operation which may simplify |
-// or obviate the need for further checks at some character positions. |
-void TextNode::TextEmitPass(RegExpCompiler* compiler, |
- TextEmitPassType pass, |
- bool preloaded, |
- Trace* trace, |
- bool first_element_checked, |
- int* checked_up_to) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- Isolate* isolate = assembler->isolate(); |
- bool one_byte = compiler->one_byte(); |
- Label* backtrack = trace->backtrack(); |
- QuickCheckDetails* quick_check = trace->quick_check_performed(); |
- int element_count = elms_->length(); |
- for (int i = preloaded ? 0 : element_count - 1; i >= 0; i--) { |
- TextElement elm = elms_->at(i); |
- int cp_offset = trace->cp_offset() + elm.cp_offset(); |
- if (elm.text_type() == TextElement::ATOM) { |
- Vector<const uc16> quarks = elm.atom()->data(); |
- for (int j = preloaded ? 0 : quarks.length() - 1; j >= 0; j--) { |
- if (first_element_checked && i == 0 && j == 0) continue; |
- if (DeterminedAlready(quick_check, elm.cp_offset() + j)) continue; |
- EmitCharacterFunction* emit_function = NULL; |
- switch (pass) { |
- case NON_LATIN1_MATCH: |
- DCHECK(one_byte); |
- if (quarks[j] > String::kMaxOneByteCharCode) { |
- assembler->GoTo(backtrack); |
- return; |
- } |
- break; |
- case NON_LETTER_CHARACTER_MATCH: |
- emit_function = &EmitAtomNonLetter; |
- break; |
- case SIMPLE_CHARACTER_MATCH: |
- emit_function = &EmitSimpleCharacter; |
- break; |
- case CASE_CHARACTER_MATCH: |
- emit_function = &EmitAtomLetter; |
- break; |
- default: |
- break; |
- } |
- if (emit_function != NULL) { |
- bool bound_checked = emit_function(isolate, |
- compiler, |
- quarks[j], |
- backtrack, |
- cp_offset + j, |
- *checked_up_to < cp_offset + j, |
- preloaded); |
- if (bound_checked) UpdateBoundsCheck(cp_offset + j, checked_up_to); |
- } |
- } |
- } else { |
- DCHECK_EQ(TextElement::CHAR_CLASS, elm.text_type()); |
- if (pass == CHARACTER_CLASS_MATCH) { |
- if (first_element_checked && i == 0) continue; |
- if (DeterminedAlready(quick_check, elm.cp_offset())) continue; |
- RegExpCharacterClass* cc = elm.char_class(); |
- EmitCharClass(assembler, cc, one_byte, backtrack, cp_offset, |
- *checked_up_to < cp_offset, preloaded, zone()); |
- UpdateBoundsCheck(cp_offset, checked_up_to); |
- } |
- } |
- } |
-} |
- |
- |
-int TextNode::Length() { |
- TextElement elm = elms_->last(); |
- DCHECK(elm.cp_offset() >= 0); |
- return elm.cp_offset() + elm.length(); |
-} |
- |
- |
-bool TextNode::SkipPass(int int_pass, bool ignore_case) { |
- TextEmitPassType pass = static_cast<TextEmitPassType>(int_pass); |
- if (ignore_case) { |
- return pass == SIMPLE_CHARACTER_MATCH; |
- } else { |
- return pass == NON_LETTER_CHARACTER_MATCH || pass == CASE_CHARACTER_MATCH; |
- } |
-} |
- |
- |
-// This generates the code to match a text node. A text node can contain |
-// straight character sequences (possibly to be matched in a case-independent |
-// way) and character classes. For efficiency we do not do this in a single |
-// pass from left to right. Instead we pass over the text node several times, |
-// emitting code for some character positions every time. See the comment on |
-// TextEmitPass for details. |
-void TextNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- LimitResult limit_result = LimitVersions(compiler, trace); |
- if (limit_result == DONE) return; |
- DCHECK(limit_result == CONTINUE); |
- |
- if (trace->cp_offset() + Length() > RegExpMacroAssembler::kMaxCPOffset) { |
- compiler->SetRegExpTooBig(); |
- return; |
- } |
- |
- if (compiler->one_byte()) { |
- int dummy = 0; |
- TextEmitPass(compiler, NON_LATIN1_MATCH, false, trace, false, &dummy); |
- } |
- |
- bool first_elt_done = false; |
- int bound_checked_to = trace->cp_offset() - 1; |
- bound_checked_to += trace->bound_checked_up_to(); |
- |
- // If a character is preloaded into the current character register then |
- // check that now. |
- if (trace->characters_preloaded() == 1) { |
- for (int pass = kFirstRealPass; pass <= kLastPass; pass++) { |
- if (!SkipPass(pass, compiler->ignore_case())) { |
- TextEmitPass(compiler, |
- static_cast<TextEmitPassType>(pass), |
- true, |
- trace, |
- false, |
- &bound_checked_to); |
- } |
- } |
- first_elt_done = true; |
- } |
- |
- for (int pass = kFirstRealPass; pass <= kLastPass; pass++) { |
- if (!SkipPass(pass, compiler->ignore_case())) { |
- TextEmitPass(compiler, |
- static_cast<TextEmitPassType>(pass), |
- false, |
- trace, |
- first_elt_done, |
- &bound_checked_to); |
- } |
- } |
- |
- Trace successor_trace(*trace); |
- successor_trace.set_at_start(false); |
- successor_trace.AdvanceCurrentPositionInTrace(Length(), compiler); |
- RecursionCheck rc(compiler); |
- on_success()->Emit(compiler, &successor_trace); |
-} |
- |
- |
-void Trace::InvalidateCurrentCharacter() { |
- characters_preloaded_ = 0; |
-} |
- |
- |
-void Trace::AdvanceCurrentPositionInTrace(int by, RegExpCompiler* compiler) { |
- DCHECK(by > 0); |
- // We don't have an instruction for shifting the current character register |
- // down or for using a shifted value for anything so lets just forget that |
- // we preloaded any characters into it. |
- characters_preloaded_ = 0; |
- // Adjust the offsets of the quick check performed information. This |
- // information is used to find out what we already determined about the |
- // characters by means of mask and compare. |
- quick_check_performed_.Advance(by, compiler->one_byte()); |
- cp_offset_ += by; |
- if (cp_offset_ > RegExpMacroAssembler::kMaxCPOffset) { |
- compiler->SetRegExpTooBig(); |
- cp_offset_ = 0; |
- } |
- bound_checked_up_to_ = Max(0, bound_checked_up_to_ - by); |
-} |
- |
- |
-void TextNode::MakeCaseIndependent(Isolate* isolate, bool is_one_byte) { |
- int element_count = elms_->length(); |
- for (int i = 0; i < element_count; i++) { |
- TextElement elm = elms_->at(i); |
- if (elm.text_type() == TextElement::CHAR_CLASS) { |
- RegExpCharacterClass* cc = elm.char_class(); |
- // None of the standard character classes is different in the case |
- // independent case and it slows us down if we don't know that. |
- if (cc->is_standard(zone())) continue; |
- ZoneList<CharacterRange>* ranges = cc->ranges(zone()); |
- int range_count = ranges->length(); |
- for (int j = 0; j < range_count; j++) { |
- ranges->at(j).AddCaseEquivalents(isolate, zone(), ranges, is_one_byte); |
- } |
- } |
- } |
-} |
- |
- |
-int TextNode::GreedyLoopTextLength() { |
- TextElement elm = elms_->at(elms_->length() - 1); |
- return elm.cp_offset() + elm.length(); |
-} |
- |
- |
-RegExpNode* TextNode::GetSuccessorOfOmnivorousTextNode( |
- RegExpCompiler* compiler) { |
- if (elms_->length() != 1) return NULL; |
- TextElement elm = elms_->at(0); |
- if (elm.text_type() != TextElement::CHAR_CLASS) return NULL; |
- RegExpCharacterClass* node = elm.char_class(); |
- ZoneList<CharacterRange>* ranges = node->ranges(zone()); |
- if (!CharacterRange::IsCanonical(ranges)) { |
- CharacterRange::Canonicalize(ranges); |
- } |
- if (node->is_negated()) { |
- return ranges->length() == 0 ? on_success() : NULL; |
- } |
- if (ranges->length() != 1) return NULL; |
- uint32_t max_char; |
- if (compiler->one_byte()) { |
- max_char = String::kMaxOneByteCharCode; |
- } else { |
- max_char = String::kMaxUtf16CodeUnit; |
- } |
- return ranges->at(0).IsEverything(max_char) ? on_success() : NULL; |
-} |
- |
- |
-// Finds the fixed match length of a sequence of nodes that goes from |
-// this alternative and back to this choice node. If there are variable |
-// length nodes or other complications in the way then return a sentinel |
-// value indicating that a greedy loop cannot be constructed. |
-int ChoiceNode::GreedyLoopTextLengthForAlternative( |
- GuardedAlternative* alternative) { |
- int length = 0; |
- RegExpNode* node = alternative->node(); |
- // Later we will generate code for all these text nodes using recursion |
- // so we have to limit the max number. |
- int recursion_depth = 0; |
- while (node != this) { |
- if (recursion_depth++ > RegExpCompiler::kMaxRecursion) { |
- return kNodeIsTooComplexForGreedyLoops; |
- } |
- int node_length = node->GreedyLoopTextLength(); |
- if (node_length == kNodeIsTooComplexForGreedyLoops) { |
- return kNodeIsTooComplexForGreedyLoops; |
- } |
- length += node_length; |
- SeqRegExpNode* seq_node = static_cast<SeqRegExpNode*>(node); |
- node = seq_node->on_success(); |
- } |
- return length; |
-} |
- |
- |
-void LoopChoiceNode::AddLoopAlternative(GuardedAlternative alt) { |
- DCHECK_NULL(loop_node_); |
- AddAlternative(alt); |
- loop_node_ = alt.node(); |
-} |
- |
- |
-void LoopChoiceNode::AddContinueAlternative(GuardedAlternative alt) { |
- DCHECK_NULL(continue_node_); |
- AddAlternative(alt); |
- continue_node_ = alt.node(); |
-} |
- |
- |
-void LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- if (trace->stop_node() == this) { |
- // Back edge of greedy optimized loop node graph. |
- int text_length = |
- GreedyLoopTextLengthForAlternative(&(alternatives_->at(0))); |
- DCHECK(text_length != kNodeIsTooComplexForGreedyLoops); |
- // Update the counter-based backtracking info on the stack. This is an |
- // optimization for greedy loops (see below). |
- DCHECK(trace->cp_offset() == text_length); |
- macro_assembler->AdvanceCurrentPosition(text_length); |
- macro_assembler->GoTo(trace->loop_label()); |
- return; |
- } |
- DCHECK_NULL(trace->stop_node()); |
- if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- return; |
- } |
- ChoiceNode::Emit(compiler, trace); |
-} |
- |
- |
-int ChoiceNode::CalculatePreloadCharacters(RegExpCompiler* compiler, |
- int eats_at_least) { |
- int preload_characters = Min(4, eats_at_least); |
- if (compiler->macro_assembler()->CanReadUnaligned()) { |
- bool one_byte = compiler->one_byte(); |
- if (one_byte) { |
- if (preload_characters > 4) preload_characters = 4; |
- // We can't preload 3 characters because there is no machine instruction |
- // to do that. We can't just load 4 because we could be reading |
- // beyond the end of the string, which could cause a memory fault. |
- if (preload_characters == 3) preload_characters = 2; |
- } else { |
- if (preload_characters > 2) preload_characters = 2; |
- } |
- } else { |
- if (preload_characters > 1) preload_characters = 1; |
- } |
- return preload_characters; |
-} |
- |
- |
-// This class is used when generating the alternatives in a choice node. It |
-// records the way the alternative is being code generated. |
-class AlternativeGeneration: public Malloced { |
- public: |
- AlternativeGeneration() |
- : possible_success(), |
- expects_preload(false), |
- after(), |
- quick_check_details() { } |
- Label possible_success; |
- bool expects_preload; |
- Label after; |
- QuickCheckDetails quick_check_details; |
-}; |
- |
- |
-// Creates a list of AlternativeGenerations. If the list has a reasonable |
-// size then it is on the stack, otherwise the excess is on the heap. |
-class AlternativeGenerationList { |
- public: |
- AlternativeGenerationList(int count, Zone* zone) |
- : alt_gens_(count, zone) { |
- for (int i = 0; i < count && i < kAFew; i++) { |
- alt_gens_.Add(a_few_alt_gens_ + i, zone); |
- } |
- for (int i = kAFew; i < count; i++) { |
- alt_gens_.Add(new AlternativeGeneration(), zone); |
- } |
- } |
- ~AlternativeGenerationList() { |
- for (int i = kAFew; i < alt_gens_.length(); i++) { |
- delete alt_gens_[i]; |
- alt_gens_[i] = NULL; |
- } |
- } |
- |
- AlternativeGeneration* at(int i) { |
- return alt_gens_[i]; |
- } |
- |
- private: |
- static const int kAFew = 10; |
- ZoneList<AlternativeGeneration*> alt_gens_; |
- AlternativeGeneration a_few_alt_gens_[kAFew]; |
-}; |
- |
- |
-// The '2' variant is has inclusive from and exclusive to. |
-// This covers \s as defined in ECMA-262 5.1, 15.10.2.12, |
-// which include WhiteSpace (7.2) or LineTerminator (7.3) values. |
-static const int kSpaceRanges[] = { '\t', '\r' + 1, ' ', ' ' + 1, |
- 0x00A0, 0x00A1, 0x1680, 0x1681, 0x180E, 0x180F, 0x2000, 0x200B, |
- 0x2028, 0x202A, 0x202F, 0x2030, 0x205F, 0x2060, 0x3000, 0x3001, |
- 0xFEFF, 0xFF00, 0x10000 }; |
-static const int kSpaceRangeCount = arraysize(kSpaceRanges); |
- |
-static const int kWordRanges[] = { |
- '0', '9' + 1, 'A', 'Z' + 1, '_', '_' + 1, 'a', 'z' + 1, 0x10000 }; |
-static const int kWordRangeCount = arraysize(kWordRanges); |
-static const int kDigitRanges[] = { '0', '9' + 1, 0x10000 }; |
-static const int kDigitRangeCount = arraysize(kDigitRanges); |
-static const int kSurrogateRanges[] = { 0xd800, 0xe000, 0x10000 }; |
-static const int kSurrogateRangeCount = arraysize(kSurrogateRanges); |
-static const int kLineTerminatorRanges[] = { 0x000A, 0x000B, 0x000D, 0x000E, |
- 0x2028, 0x202A, 0x10000 }; |
-static const int kLineTerminatorRangeCount = arraysize(kLineTerminatorRanges); |
- |
- |
-void BoyerMoorePositionInfo::Set(int character) { |
- SetInterval(Interval(character, character)); |
-} |
- |
- |
-void BoyerMoorePositionInfo::SetInterval(const Interval& interval) { |
- s_ = AddRange(s_, kSpaceRanges, kSpaceRangeCount, interval); |
- w_ = AddRange(w_, kWordRanges, kWordRangeCount, interval); |
- d_ = AddRange(d_, kDigitRanges, kDigitRangeCount, interval); |
- surrogate_ = |
- AddRange(surrogate_, kSurrogateRanges, kSurrogateRangeCount, interval); |
- if (interval.to() - interval.from() >= kMapSize - 1) { |
- if (map_count_ != kMapSize) { |
- map_count_ = kMapSize; |
- for (int i = 0; i < kMapSize; i++) map_->at(i) = true; |
- } |
- return; |
- } |
- for (int i = interval.from(); i <= interval.to(); i++) { |
- int mod_character = (i & kMask); |
- if (!map_->at(mod_character)) { |
- map_count_++; |
- map_->at(mod_character) = true; |
- } |
- if (map_count_ == kMapSize) return; |
- } |
-} |
- |
- |
-void BoyerMoorePositionInfo::SetAll() { |
- s_ = w_ = d_ = kLatticeUnknown; |
- if (map_count_ != kMapSize) { |
- map_count_ = kMapSize; |
- for (int i = 0; i < kMapSize; i++) map_->at(i) = true; |
- } |
-} |
- |
- |
-BoyerMooreLookahead::BoyerMooreLookahead( |
- int length, RegExpCompiler* compiler, Zone* zone) |
- : length_(length), |
- compiler_(compiler) { |
- if (compiler->one_byte()) { |
- max_char_ = String::kMaxOneByteCharCode; |
- } else { |
- max_char_ = String::kMaxUtf16CodeUnit; |
- } |
- bitmaps_ = new(zone) ZoneList<BoyerMoorePositionInfo*>(length, zone); |
- for (int i = 0; i < length; i++) { |
- bitmaps_->Add(new(zone) BoyerMoorePositionInfo(zone), zone); |
- } |
-} |
- |
- |
-// Find the longest range of lookahead that has the fewest number of different |
-// characters that can occur at a given position. Since we are optimizing two |
-// different parameters at once this is a tradeoff. |
-bool BoyerMooreLookahead::FindWorthwhileInterval(int* from, int* to) { |
- int biggest_points = 0; |
- // If more than 32 characters out of 128 can occur it is unlikely that we can |
- // be lucky enough to step forwards much of the time. |
- const int kMaxMax = 32; |
- for (int max_number_of_chars = 4; |
- max_number_of_chars < kMaxMax; |
- max_number_of_chars *= 2) { |
- biggest_points = |
- FindBestInterval(max_number_of_chars, biggest_points, from, to); |
- } |
- if (biggest_points == 0) return false; |
- return true; |
-} |
- |
- |
-// Find the highest-points range between 0 and length_ where the character |
-// information is not too vague. 'Too vague' means that there are more than |
-// max_number_of_chars that can occur at this position. Calculates the number |
-// of points as the product of width-of-the-range and |
-// probability-of-finding-one-of-the-characters, where the probability is |
-// calculated using the frequency distribution of the sample subject string. |
-int BoyerMooreLookahead::FindBestInterval( |
- int max_number_of_chars, int old_biggest_points, int* from, int* to) { |
- int biggest_points = old_biggest_points; |
- static const int kSize = RegExpMacroAssembler::kTableSize; |
- for (int i = 0; i < length_; ) { |
- while (i < length_ && Count(i) > max_number_of_chars) i++; |
- if (i == length_) break; |
- int remembered_from = i; |
- bool union_map[kSize]; |
- for (int j = 0; j < kSize; j++) union_map[j] = false; |
- while (i < length_ && Count(i) <= max_number_of_chars) { |
- BoyerMoorePositionInfo* map = bitmaps_->at(i); |
- for (int j = 0; j < kSize; j++) union_map[j] |= map->at(j); |
- i++; |
- } |
- int frequency = 0; |
- for (int j = 0; j < kSize; j++) { |
- if (union_map[j]) { |
- // Add 1 to the frequency to give a small per-character boost for |
- // the cases where our sampling is not good enough and many |
- // characters have a frequency of zero. This means the frequency |
- // can theoretically be up to 2*kSize though we treat it mostly as |
- // a fraction of kSize. |
- frequency += compiler_->frequency_collator()->Frequency(j) + 1; |
- } |
- } |
- // We use the probability of skipping times the distance we are skipping to |
- // judge the effectiveness of this. Actually we have a cut-off: By |
- // dividing by 2 we switch off the skipping if the probability of skipping |
- // is less than 50%. This is because the multibyte mask-and-compare |
- // skipping in quickcheck is more likely to do well on this case. |
- bool in_quickcheck_range = |
- ((i - remembered_from < 4) || |
- (compiler_->one_byte() ? remembered_from <= 4 : remembered_from <= 2)); |
- // Called 'probability' but it is only a rough estimate and can actually |
- // be outside the 0-kSize range. |
- int probability = (in_quickcheck_range ? kSize / 2 : kSize) - frequency; |
- int points = (i - remembered_from) * probability; |
- if (points > biggest_points) { |
- *from = remembered_from; |
- *to = i - 1; |
- biggest_points = points; |
- } |
- } |
- return biggest_points; |
-} |
- |
- |
-// Take all the characters that will not prevent a successful match if they |
-// occur in the subject string in the range between min_lookahead and |
-// max_lookahead (inclusive) measured from the current position. If the |
-// character at max_lookahead offset is not one of these characters, then we |
-// can safely skip forwards by the number of characters in the range. |
-int BoyerMooreLookahead::GetSkipTable(int min_lookahead, |
- int max_lookahead, |
- Handle<ByteArray> boolean_skip_table) { |
- const int kSize = RegExpMacroAssembler::kTableSize; |
- |
- const int kSkipArrayEntry = 0; |
- const int kDontSkipArrayEntry = 1; |
- |
- for (int i = 0; i < kSize; i++) { |
- boolean_skip_table->set(i, kSkipArrayEntry); |
- } |
- int skip = max_lookahead + 1 - min_lookahead; |
- |
- for (int i = max_lookahead; i >= min_lookahead; i--) { |
- BoyerMoorePositionInfo* map = bitmaps_->at(i); |
- for (int j = 0; j < kSize; j++) { |
- if (map->at(j)) { |
- boolean_skip_table->set(j, kDontSkipArrayEntry); |
- } |
- } |
- } |
- |
- return skip; |
-} |
- |
- |
-// See comment above on the implementation of GetSkipTable. |
-void BoyerMooreLookahead::EmitSkipInstructions(RegExpMacroAssembler* masm) { |
- const int kSize = RegExpMacroAssembler::kTableSize; |
- |
- int min_lookahead = 0; |
- int max_lookahead = 0; |
- |
- if (!FindWorthwhileInterval(&min_lookahead, &max_lookahead)) return; |
- |
- bool found_single_character = false; |
- int single_character = 0; |
- for (int i = max_lookahead; i >= min_lookahead; i--) { |
- BoyerMoorePositionInfo* map = bitmaps_->at(i); |
- if (map->map_count() > 1 || |
- (found_single_character && map->map_count() != 0)) { |
- found_single_character = false; |
- break; |
- } |
- for (int j = 0; j < kSize; j++) { |
- if (map->at(j)) { |
- found_single_character = true; |
- single_character = j; |
- break; |
- } |
- } |
- } |
- |
- int lookahead_width = max_lookahead + 1 - min_lookahead; |
- |
- if (found_single_character && lookahead_width == 1 && max_lookahead < 3) { |
- // The mask-compare can probably handle this better. |
- return; |
- } |
- |
- if (found_single_character) { |
- Label cont, again; |
- masm->Bind(&again); |
- masm->LoadCurrentCharacter(max_lookahead, &cont, true); |
- if (max_char_ > kSize) { |
- masm->CheckCharacterAfterAnd(single_character, |
- RegExpMacroAssembler::kTableMask, |
- &cont); |
- } else { |
- masm->CheckCharacter(single_character, &cont); |
- } |
- masm->AdvanceCurrentPosition(lookahead_width); |
- masm->GoTo(&again); |
- masm->Bind(&cont); |
- return; |
- } |
- |
- Factory* factory = masm->isolate()->factory(); |
- Handle<ByteArray> boolean_skip_table = factory->NewByteArray(kSize, TENURED); |
- int skip_distance = GetSkipTable( |
- min_lookahead, max_lookahead, boolean_skip_table); |
- DCHECK(skip_distance != 0); |
- |
- Label cont, again; |
- masm->Bind(&again); |
- masm->LoadCurrentCharacter(max_lookahead, &cont, true); |
- masm->CheckBitInTable(boolean_skip_table, &cont); |
- masm->AdvanceCurrentPosition(skip_distance); |
- masm->GoTo(&again); |
- masm->Bind(&cont); |
-} |
- |
- |
-/* Code generation for choice nodes. |
- * |
- * We generate quick checks that do a mask and compare to eliminate a |
- * choice. If the quick check succeeds then it jumps to the continuation to |
- * do slow checks and check subsequent nodes. If it fails (the common case) |
- * it falls through to the next choice. |
- * |
- * Here is the desired flow graph. Nodes directly below each other imply |
- * fallthrough. Alternatives 1 and 2 have quick checks. Alternative |
- * 3 doesn't have a quick check so we have to call the slow check. |
- * Nodes are marked Qn for quick checks and Sn for slow checks. The entire |
- * regexp continuation is generated directly after the Sn node, up to the |
- * next GoTo if we decide to reuse some already generated code. Some |
- * nodes expect preload_characters to be preloaded into the current |
- * character register. R nodes do this preloading. Vertices are marked |
- * F for failures and S for success (possible success in the case of quick |
- * nodes). L, V, < and > are used as arrow heads. |
- * |
- * ----------> R |
- * | |
- * V |
- * Q1 -----> S1 |
- * | S / |
- * F| / |
- * | F/ |
- * | / |
- * | R |
- * | / |
- * V L |
- * Q2 -----> S2 |
- * | S / |
- * F| / |
- * | F/ |
- * | / |
- * | R |
- * | / |
- * V L |
- * S3 |
- * | |
- * F| |
- * | |
- * R |
- * | |
- * backtrack V |
- * <----------Q4 |
- * \ F | |
- * \ |S |
- * \ F V |
- * \-----S4 |
- * |
- * For greedy loops we push the current position, then generate the code that |
- * eats the input specially in EmitGreedyLoop. The other choice (the |
- * continuation) is generated by the normal code in EmitChoices, and steps back |
- * in the input to the starting position when it fails to match. The loop code |
- * looks like this (U is the unwind code that steps back in the greedy loop). |
- * |
- * _____ |
- * / \ |
- * V | |
- * ----------> S1 | |
- * /| | |
- * / |S | |
- * F/ \_____/ |
- * / |
- * |<----- |
- * | \ |
- * V |S |
- * Q2 ---> U----->backtrack |
- * | F / |
- * S| / |
- * V F / |
- * S2--/ |
- */ |
- |
-GreedyLoopState::GreedyLoopState(bool not_at_start) { |
- counter_backtrack_trace_.set_backtrack(&label_); |
- if (not_at_start) counter_backtrack_trace_.set_at_start(false); |
-} |
- |
- |
-void ChoiceNode::AssertGuardsMentionRegisters(Trace* trace) { |
-#ifdef DEBUG |
- int choice_count = alternatives_->length(); |
- for (int i = 0; i < choice_count - 1; i++) { |
- GuardedAlternative alternative = alternatives_->at(i); |
- ZoneList<Guard*>* guards = alternative.guards(); |
- int guard_count = (guards == NULL) ? 0 : guards->length(); |
- for (int j = 0; j < guard_count; j++) { |
- DCHECK(!trace->mentions_reg(guards->at(j)->reg())); |
- } |
- } |
-#endif |
-} |
- |
- |
-void ChoiceNode::SetUpPreLoad(RegExpCompiler* compiler, |
- Trace* current_trace, |
- PreloadState* state) { |
- if (state->eats_at_least_ == PreloadState::kEatsAtLeastNotYetInitialized) { |
- // Save some time by looking at most one machine word ahead. |
- state->eats_at_least_ = |
- EatsAtLeast(compiler->one_byte() ? 4 : 2, kRecursionBudget, |
- current_trace->at_start() == Trace::FALSE_VALUE); |
- } |
- state->preload_characters_ = |
- CalculatePreloadCharacters(compiler, state->eats_at_least_); |
- |
- state->preload_is_current_ = |
- (current_trace->characters_preloaded() == state->preload_characters_); |
- state->preload_has_checked_bounds_ = state->preload_is_current_; |
-} |
- |
- |
-void ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- int choice_count = alternatives_->length(); |
- |
- AssertGuardsMentionRegisters(trace); |
- |
- LimitResult limit_result = LimitVersions(compiler, trace); |
- if (limit_result == DONE) return; |
- DCHECK(limit_result == CONTINUE); |
- |
- // For loop nodes we already flushed (see LoopChoiceNode::Emit), but for |
- // other choice nodes we only flush if we are out of code size budget. |
- if (trace->flush_budget() == 0 && trace->actions() != NULL) { |
- trace->Flush(compiler, this); |
- return; |
- } |
- |
- RecursionCheck rc(compiler); |
- |
- PreloadState preload; |
- preload.init(); |
- GreedyLoopState greedy_loop_state(not_at_start()); |
- |
- int text_length = GreedyLoopTextLengthForAlternative(&alternatives_->at(0)); |
- AlternativeGenerationList alt_gens(choice_count, zone()); |
- |
- if (choice_count > 1 && text_length != kNodeIsTooComplexForGreedyLoops) { |
- trace = EmitGreedyLoop(compiler, |
- trace, |
- &alt_gens, |
- &preload, |
- &greedy_loop_state, |
- text_length); |
- } else { |
- // TODO(erikcorry): Delete this. We don't need this label, but it makes us |
- // match the traces produced pre-cleanup. |
- Label second_choice; |
- compiler->macro_assembler()->Bind(&second_choice); |
- |
- preload.eats_at_least_ = EmitOptimizedUnanchoredSearch(compiler, trace); |
- |
- EmitChoices(compiler, |
- &alt_gens, |
- 0, |
- trace, |
- &preload); |
- } |
- |
- // At this point we need to generate slow checks for the alternatives where |
- // the quick check was inlined. We can recognize these because the associated |
- // label was bound. |
- int new_flush_budget = trace->flush_budget() / choice_count; |
- for (int i = 0; i < choice_count; i++) { |
- AlternativeGeneration* alt_gen = alt_gens.at(i); |
- Trace new_trace(*trace); |
- // If there are actions to be flushed we have to limit how many times |
- // they are flushed. Take the budget of the parent trace and distribute |
- // it fairly amongst the children. |
- if (new_trace.actions() != NULL) { |
- new_trace.set_flush_budget(new_flush_budget); |
- } |
- bool next_expects_preload = |
- i == choice_count - 1 ? false : alt_gens.at(i + 1)->expects_preload; |
- EmitOutOfLineContinuation(compiler, |
- &new_trace, |
- alternatives_->at(i), |
- alt_gen, |
- preload.preload_characters_, |
- next_expects_preload); |
- } |
-} |
- |
- |
-Trace* ChoiceNode::EmitGreedyLoop(RegExpCompiler* compiler, |
- Trace* trace, |
- AlternativeGenerationList* alt_gens, |
- PreloadState* preload, |
- GreedyLoopState* greedy_loop_state, |
- int text_length) { |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- // Here we have special handling for greedy loops containing only text nodes |
- // and other simple nodes. These are handled by pushing the current |
- // position on the stack and then incrementing the current position each |
- // time around the switch. On backtrack we decrement the current position |
- // and check it against the pushed value. This avoids pushing backtrack |
- // information for each iteration of the loop, which could take up a lot of |
- // space. |
- DCHECK(trace->stop_node() == NULL); |
- macro_assembler->PushCurrentPosition(); |
- Label greedy_match_failed; |
- Trace greedy_match_trace; |
- if (not_at_start()) greedy_match_trace.set_at_start(false); |
- greedy_match_trace.set_backtrack(&greedy_match_failed); |
- Label loop_label; |
- macro_assembler->Bind(&loop_label); |
- greedy_match_trace.set_stop_node(this); |
- greedy_match_trace.set_loop_label(&loop_label); |
- alternatives_->at(0).node()->Emit(compiler, &greedy_match_trace); |
- macro_assembler->Bind(&greedy_match_failed); |
- |
- Label second_choice; // For use in greedy matches. |
- macro_assembler->Bind(&second_choice); |
- |
- Trace* new_trace = greedy_loop_state->counter_backtrack_trace(); |
- |
- EmitChoices(compiler, |
- alt_gens, |
- 1, |
- new_trace, |
- preload); |
- |
- macro_assembler->Bind(greedy_loop_state->label()); |
- // If we have unwound to the bottom then backtrack. |
- macro_assembler->CheckGreedyLoop(trace->backtrack()); |
- // Otherwise try the second priority at an earlier position. |
- macro_assembler->AdvanceCurrentPosition(-text_length); |
- macro_assembler->GoTo(&second_choice); |
- return new_trace; |
-} |
- |
-int ChoiceNode::EmitOptimizedUnanchoredSearch(RegExpCompiler* compiler, |
- Trace* trace) { |
- int eats_at_least = PreloadState::kEatsAtLeastNotYetInitialized; |
- if (alternatives_->length() != 2) return eats_at_least; |
- |
- GuardedAlternative alt1 = alternatives_->at(1); |
- if (alt1.guards() != NULL && alt1.guards()->length() != 0) { |
- return eats_at_least; |
- } |
- RegExpNode* eats_anything_node = alt1.node(); |
- if (eats_anything_node->GetSuccessorOfOmnivorousTextNode(compiler) != this) { |
- return eats_at_least; |
- } |
- |
- // Really we should be creating a new trace when we execute this function, |
- // but there is no need, because the code it generates cannot backtrack, and |
- // we always arrive here with a trivial trace (since it's the entry to a |
- // loop. That also implies that there are no preloaded characters, which is |
- // good, because it means we won't be violating any assumptions by |
- // overwriting those characters with new load instructions. |
- DCHECK(trace->is_trivial()); |
- |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- Isolate* isolate = macro_assembler->isolate(); |
- // At this point we know that we are at a non-greedy loop that will eat |
- // any character one at a time. Any non-anchored regexp has such a |
- // loop prepended to it in order to find where it starts. We look for |
- // a pattern of the form ...abc... where we can look 6 characters ahead |
- // and step forwards 3 if the character is not one of abc. Abc need |
- // not be atoms, they can be any reasonably limited character class or |
- // small alternation. |
- BoyerMooreLookahead* bm = bm_info(false); |
- if (bm == NULL) { |
- eats_at_least = Min(kMaxLookaheadForBoyerMoore, |
- EatsAtLeast(kMaxLookaheadForBoyerMoore, |
- kRecursionBudget, |
- false)); |
- if (eats_at_least >= 1) { |
- bm = new(zone()) BoyerMooreLookahead(eats_at_least, |
- compiler, |
- zone()); |
- GuardedAlternative alt0 = alternatives_->at(0); |
- alt0.node()->FillInBMInfo(isolate, 0, kRecursionBudget, bm, false); |
- } |
- } |
- if (bm != NULL) { |
- bm->EmitSkipInstructions(macro_assembler); |
- } |
- return eats_at_least; |
-} |
- |
- |
-void ChoiceNode::EmitChoices(RegExpCompiler* compiler, |
- AlternativeGenerationList* alt_gens, |
- int first_choice, |
- Trace* trace, |
- PreloadState* preload) { |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- SetUpPreLoad(compiler, trace, preload); |
- |
- // For now we just call all choices one after the other. The idea ultimately |
- // is to use the Dispatch table to try only the relevant ones. |
- int choice_count = alternatives_->length(); |
- |
- int new_flush_budget = trace->flush_budget() / choice_count; |
- |
- for (int i = first_choice; i < choice_count; i++) { |
- bool is_last = i == choice_count - 1; |
- bool fall_through_on_failure = !is_last; |
- GuardedAlternative alternative = alternatives_->at(i); |
- AlternativeGeneration* alt_gen = alt_gens->at(i); |
- alt_gen->quick_check_details.set_characters(preload->preload_characters_); |
- ZoneList<Guard*>* guards = alternative.guards(); |
- int guard_count = (guards == NULL) ? 0 : guards->length(); |
- Trace new_trace(*trace); |
- new_trace.set_characters_preloaded(preload->preload_is_current_ ? |
- preload->preload_characters_ : |
- 0); |
- if (preload->preload_has_checked_bounds_) { |
- new_trace.set_bound_checked_up_to(preload->preload_characters_); |
- } |
- new_trace.quick_check_performed()->Clear(); |
- if (not_at_start_) new_trace.set_at_start(Trace::FALSE_VALUE); |
- if (!is_last) { |
- new_trace.set_backtrack(&alt_gen->after); |
- } |
- alt_gen->expects_preload = preload->preload_is_current_; |
- bool generate_full_check_inline = false; |
- if (compiler->optimize() && |
- try_to_emit_quick_check_for_alternative(i == 0) && |
- alternative.node()->EmitQuickCheck( |
- compiler, trace, &new_trace, preload->preload_has_checked_bounds_, |
- &alt_gen->possible_success, &alt_gen->quick_check_details, |
- fall_through_on_failure)) { |
- // Quick check was generated for this choice. |
- preload->preload_is_current_ = true; |
- preload->preload_has_checked_bounds_ = true; |
- // If we generated the quick check to fall through on possible success, |
- // we now need to generate the full check inline. |
- if (!fall_through_on_failure) { |
- macro_assembler->Bind(&alt_gen->possible_success); |
- new_trace.set_quick_check_performed(&alt_gen->quick_check_details); |
- new_trace.set_characters_preloaded(preload->preload_characters_); |
- new_trace.set_bound_checked_up_to(preload->preload_characters_); |
- generate_full_check_inline = true; |
- } |
- } else if (alt_gen->quick_check_details.cannot_match()) { |
- if (!fall_through_on_failure) { |
- macro_assembler->GoTo(trace->backtrack()); |
- } |
- continue; |
- } else { |
- // No quick check was generated. Put the full code here. |
- // If this is not the first choice then there could be slow checks from |
- // previous cases that go here when they fail. There's no reason to |
- // insist that they preload characters since the slow check we are about |
- // to generate probably can't use it. |
- if (i != first_choice) { |
- alt_gen->expects_preload = false; |
- new_trace.InvalidateCurrentCharacter(); |
- } |
- generate_full_check_inline = true; |
- } |
- if (generate_full_check_inline) { |
- if (new_trace.actions() != NULL) { |
- new_trace.set_flush_budget(new_flush_budget); |
- } |
- for (int j = 0; j < guard_count; j++) { |
- GenerateGuard(macro_assembler, guards->at(j), &new_trace); |
- } |
- alternative.node()->Emit(compiler, &new_trace); |
- preload->preload_is_current_ = false; |
- } |
- macro_assembler->Bind(&alt_gen->after); |
- } |
-} |
- |
- |
-void ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler, |
- Trace* trace, |
- GuardedAlternative alternative, |
- AlternativeGeneration* alt_gen, |
- int preload_characters, |
- bool next_expects_preload) { |
- if (!alt_gen->possible_success.is_linked()) return; |
- |
- RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
- macro_assembler->Bind(&alt_gen->possible_success); |
- Trace out_of_line_trace(*trace); |
- out_of_line_trace.set_characters_preloaded(preload_characters); |
- out_of_line_trace.set_quick_check_performed(&alt_gen->quick_check_details); |
- if (not_at_start_) out_of_line_trace.set_at_start(Trace::FALSE_VALUE); |
- ZoneList<Guard*>* guards = alternative.guards(); |
- int guard_count = (guards == NULL) ? 0 : guards->length(); |
- if (next_expects_preload) { |
- Label reload_current_char; |
- out_of_line_trace.set_backtrack(&reload_current_char); |
- for (int j = 0; j < guard_count; j++) { |
- GenerateGuard(macro_assembler, guards->at(j), &out_of_line_trace); |
- } |
- alternative.node()->Emit(compiler, &out_of_line_trace); |
- macro_assembler->Bind(&reload_current_char); |
- // Reload the current character, since the next quick check expects that. |
- // We don't need to check bounds here because we only get into this |
- // code through a quick check which already did the checked load. |
- macro_assembler->LoadCurrentCharacter(trace->cp_offset(), |
- NULL, |
- false, |
- preload_characters); |
- macro_assembler->GoTo(&(alt_gen->after)); |
- } else { |
- out_of_line_trace.set_backtrack(&(alt_gen->after)); |
- for (int j = 0; j < guard_count; j++) { |
- GenerateGuard(macro_assembler, guards->at(j), &out_of_line_trace); |
- } |
- alternative.node()->Emit(compiler, &out_of_line_trace); |
- } |
-} |
- |
- |
-void ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- LimitResult limit_result = LimitVersions(compiler, trace); |
- if (limit_result == DONE) return; |
- DCHECK(limit_result == CONTINUE); |
- |
- RecursionCheck rc(compiler); |
- |
- switch (action_type_) { |
- case STORE_POSITION: { |
- Trace::DeferredCapture |
- new_capture(data_.u_position_register.reg, |
- data_.u_position_register.is_capture, |
- trace); |
- Trace new_trace = *trace; |
- new_trace.add_action(&new_capture); |
- on_success()->Emit(compiler, &new_trace); |
- break; |
- } |
- case INCREMENT_REGISTER: { |
- Trace::DeferredIncrementRegister |
- new_increment(data_.u_increment_register.reg); |
- Trace new_trace = *trace; |
- new_trace.add_action(&new_increment); |
- on_success()->Emit(compiler, &new_trace); |
- break; |
- } |
- case SET_REGISTER: { |
- Trace::DeferredSetRegister |
- new_set(data_.u_store_register.reg, data_.u_store_register.value); |
- Trace new_trace = *trace; |
- new_trace.add_action(&new_set); |
- on_success()->Emit(compiler, &new_trace); |
- break; |
- } |
- case CLEAR_CAPTURES: { |
- Trace::DeferredClearCaptures |
- new_capture(Interval(data_.u_clear_captures.range_from, |
- data_.u_clear_captures.range_to)); |
- Trace new_trace = *trace; |
- new_trace.add_action(&new_capture); |
- on_success()->Emit(compiler, &new_trace); |
- break; |
- } |
- case BEGIN_SUBMATCH: |
- if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- } else { |
- assembler->WriteCurrentPositionToRegister( |
- data_.u_submatch.current_position_register, 0); |
- assembler->WriteStackPointerToRegister( |
- data_.u_submatch.stack_pointer_register); |
- on_success()->Emit(compiler, trace); |
- } |
- break; |
- case EMPTY_MATCH_CHECK: { |
- int start_pos_reg = data_.u_empty_match_check.start_register; |
- int stored_pos = 0; |
- int rep_reg = data_.u_empty_match_check.repetition_register; |
- bool has_minimum = (rep_reg != RegExpCompiler::kNoRegister); |
- bool know_dist = trace->GetStoredPosition(start_pos_reg, &stored_pos); |
- if (know_dist && !has_minimum && stored_pos == trace->cp_offset()) { |
- // If we know we haven't advanced and there is no minimum we |
- // can just backtrack immediately. |
- assembler->GoTo(trace->backtrack()); |
- } else if (know_dist && stored_pos < trace->cp_offset()) { |
- // If we know we've advanced we can generate the continuation |
- // immediately. |
- on_success()->Emit(compiler, trace); |
- } else if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- } else { |
- Label skip_empty_check; |
- // If we have a minimum number of repetitions we check the current |
- // number first and skip the empty check if it's not enough. |
- if (has_minimum) { |
- int limit = data_.u_empty_match_check.repetition_limit; |
- assembler->IfRegisterLT(rep_reg, limit, &skip_empty_check); |
- } |
- // If the match is empty we bail out, otherwise we fall through |
- // to the on-success continuation. |
- assembler->IfRegisterEqPos(data_.u_empty_match_check.start_register, |
- trace->backtrack()); |
- assembler->Bind(&skip_empty_check); |
- on_success()->Emit(compiler, trace); |
- } |
- break; |
- } |
- case POSITIVE_SUBMATCH_SUCCESS: { |
- if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- return; |
- } |
- assembler->ReadCurrentPositionFromRegister( |
- data_.u_submatch.current_position_register); |
- assembler->ReadStackPointerFromRegister( |
- data_.u_submatch.stack_pointer_register); |
- int clear_register_count = data_.u_submatch.clear_register_count; |
- if (clear_register_count == 0) { |
- on_success()->Emit(compiler, trace); |
- return; |
- } |
- int clear_registers_from = data_.u_submatch.clear_register_from; |
- Label clear_registers_backtrack; |
- Trace new_trace = *trace; |
- new_trace.set_backtrack(&clear_registers_backtrack); |
- on_success()->Emit(compiler, &new_trace); |
- |
- assembler->Bind(&clear_registers_backtrack); |
- int clear_registers_to = clear_registers_from + clear_register_count - 1; |
- assembler->ClearRegisters(clear_registers_from, clear_registers_to); |
- |
- DCHECK(trace->backtrack() == NULL); |
- assembler->Backtrack(); |
- return; |
- } |
- default: |
- UNREACHABLE(); |
- } |
-} |
- |
- |
-void BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
- RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
- if (!trace->is_trivial()) { |
- trace->Flush(compiler, this); |
- return; |
- } |
- |
- LimitResult limit_result = LimitVersions(compiler, trace); |
- if (limit_result == DONE) return; |
- DCHECK(limit_result == CONTINUE); |
- |
- RecursionCheck rc(compiler); |
- |
- DCHECK_EQ(start_reg_ + 1, end_reg_); |
- if (compiler->ignore_case()) { |
- assembler->CheckNotBackReferenceIgnoreCase(start_reg_, |
- trace->backtrack()); |
- } else { |
- assembler->CheckNotBackReference(start_reg_, trace->backtrack()); |
- } |
- on_success()->Emit(compiler, trace); |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Dot/dotty output |
- |
- |
-#ifdef DEBUG |
- |
- |
-class DotPrinter: public NodeVisitor { |
- public: |
- DotPrinter(std::ostream& os, bool ignore_case) // NOLINT |
- : os_(os), |
- ignore_case_(ignore_case) {} |
- void PrintNode(const char* label, RegExpNode* node); |
- void Visit(RegExpNode* node); |
- void PrintAttributes(RegExpNode* from); |
- void PrintOnFailure(RegExpNode* from, RegExpNode* to); |
-#define DECLARE_VISIT(Type) \ |
- virtual void Visit##Type(Type##Node* that); |
-FOR_EACH_NODE_TYPE(DECLARE_VISIT) |
-#undef DECLARE_VISIT |
- private: |
- std::ostream& os_; |
- bool ignore_case_; |
-}; |
- |
- |
-void DotPrinter::PrintNode(const char* label, RegExpNode* node) { |
- os_ << "digraph G {\n graph [label=\""; |
- for (int i = 0; label[i]; i++) { |
- switch (label[i]) { |
- case '\\': |
- os_ << "\\\\"; |
- break; |
- case '"': |
- os_ << "\""; |
- break; |
- default: |
- os_ << label[i]; |
- break; |
- } |
- } |
- os_ << "\"];\n"; |
- Visit(node); |
- os_ << "}" << std::endl; |
-} |
- |
- |
-void DotPrinter::Visit(RegExpNode* node) { |
- if (node->info()->visited) return; |
- node->info()->visited = true; |
- node->Accept(this); |
-} |
- |
- |
-void DotPrinter::PrintOnFailure(RegExpNode* from, RegExpNode* on_failure) { |
- os_ << " n" << from << " -> n" << on_failure << " [style=dotted];\n"; |
- Visit(on_failure); |
-} |
- |
- |
-class TableEntryBodyPrinter { |
- public: |
- TableEntryBodyPrinter(std::ostream& os, ChoiceNode* choice) // NOLINT |
- : os_(os), |
- choice_(choice) {} |
- void Call(uc16 from, DispatchTable::Entry entry) { |
- OutSet* out_set = entry.out_set(); |
- for (unsigned i = 0; i < OutSet::kFirstLimit; i++) { |
- if (out_set->Get(i)) { |
- os_ << " n" << choice() << ":s" << from << "o" << i << " -> n" |
- << choice()->alternatives()->at(i).node() << ";\n"; |
- } |
- } |
- } |
- private: |
- ChoiceNode* choice() { return choice_; } |
- std::ostream& os_; |
- ChoiceNode* choice_; |
-}; |
- |
- |
-class TableEntryHeaderPrinter { |
- public: |
- explicit TableEntryHeaderPrinter(std::ostream& os) // NOLINT |
- : first_(true), |
- os_(os) {} |
- void Call(uc16 from, DispatchTable::Entry entry) { |
- if (first_) { |
- first_ = false; |
- } else { |
- os_ << "|"; |
- } |
- os_ << "{\\" << AsUC16(from) << "-\\" << AsUC16(entry.to()) << "|{"; |
- OutSet* out_set = entry.out_set(); |
- int priority = 0; |
- for (unsigned i = 0; i < OutSet::kFirstLimit; i++) { |
- if (out_set->Get(i)) { |
- if (priority > 0) os_ << "|"; |
- os_ << "<s" << from << "o" << i << "> " << priority; |
- priority++; |
- } |
- } |
- os_ << "}}"; |
- } |
- |
- private: |
- bool first_; |
- std::ostream& os_; |
-}; |
- |
- |
-class AttributePrinter { |
- public: |
- explicit AttributePrinter(std::ostream& os) // NOLINT |
- : os_(os), |
- first_(true) {} |
- void PrintSeparator() { |
- if (first_) { |
- first_ = false; |
- } else { |
- os_ << "|"; |
- } |
- } |
- void PrintBit(const char* name, bool value) { |
- if (!value) return; |
- PrintSeparator(); |
- os_ << "{" << name << "}"; |
- } |
- void PrintPositive(const char* name, int value) { |
- if (value < 0) return; |
- PrintSeparator(); |
- os_ << "{" << name << "|" << value << "}"; |
- } |
- |
- private: |
- std::ostream& os_; |
- bool first_; |
-}; |
- |
- |
-void DotPrinter::PrintAttributes(RegExpNode* that) { |
- os_ << " a" << that << " [shape=Mrecord, color=grey, fontcolor=grey, " |
- << "margin=0.1, fontsize=10, label=\"{"; |
- AttributePrinter printer(os_); |
- NodeInfo* info = that->info(); |
- printer.PrintBit("NI", info->follows_newline_interest); |
- printer.PrintBit("WI", info->follows_word_interest); |
- printer.PrintBit("SI", info->follows_start_interest); |
- Label* label = that->label(); |
- if (label->is_bound()) |
- printer.PrintPositive("@", label->pos()); |
- os_ << "}\"];\n" |
- << " a" << that << " -> n" << that |
- << " [style=dashed, color=grey, arrowhead=none];\n"; |
-} |
- |
- |
-static const bool kPrintDispatchTable = false; |
-void DotPrinter::VisitChoice(ChoiceNode* that) { |
- if (kPrintDispatchTable) { |
- os_ << " n" << that << " [shape=Mrecord, label=\""; |
- TableEntryHeaderPrinter header_printer(os_); |
- that->GetTable(ignore_case_)->ForEach(&header_printer); |
- os_ << "\"]\n"; |
- PrintAttributes(that); |
- TableEntryBodyPrinter body_printer(os_, that); |
- that->GetTable(ignore_case_)->ForEach(&body_printer); |
- } else { |
- os_ << " n" << that << " [shape=Mrecord, label=\"?\"];\n"; |
- for (int i = 0; i < that->alternatives()->length(); i++) { |
- GuardedAlternative alt = that->alternatives()->at(i); |
- os_ << " n" << that << " -> n" << alt.node(); |
- } |
- } |
- for (int i = 0; i < that->alternatives()->length(); i++) { |
- GuardedAlternative alt = that->alternatives()->at(i); |
- alt.node()->Accept(this); |
- } |
-} |
- |
- |
-void DotPrinter::VisitText(TextNode* that) { |
- Zone* zone = that->zone(); |
- os_ << " n" << that << " [label=\""; |
- for (int i = 0; i < that->elements()->length(); i++) { |
- if (i > 0) os_ << " "; |
- TextElement elm = that->elements()->at(i); |
- switch (elm.text_type()) { |
- case TextElement::ATOM: { |
- Vector<const uc16> data = elm.atom()->data(); |
- for (int i = 0; i < data.length(); i++) { |
- os_ << static_cast<char>(data[i]); |
- } |
- break; |
- } |
- case TextElement::CHAR_CLASS: { |
- RegExpCharacterClass* node = elm.char_class(); |
- os_ << "["; |
- if (node->is_negated()) os_ << "^"; |
- for (int j = 0; j < node->ranges(zone)->length(); j++) { |
- CharacterRange range = node->ranges(zone)->at(j); |
- os_ << AsUC16(range.from()) << "-" << AsUC16(range.to()); |
- } |
- os_ << "]"; |
- break; |
- } |
- default: |
- UNREACHABLE(); |
- } |
- } |
- os_ << "\", shape=box, peripheries=2];\n"; |
- PrintAttributes(that); |
- os_ << " n" << that << " -> n" << that->on_success() << ";\n"; |
- Visit(that->on_success()); |
-} |
- |
- |
-void DotPrinter::VisitBackReference(BackReferenceNode* that) { |
- os_ << " n" << that << " [label=\"$" << that->start_register() << "..$" |
- << that->end_register() << "\", shape=doubleoctagon];\n"; |
- PrintAttributes(that); |
- os_ << " n" << that << " -> n" << that->on_success() << ";\n"; |
- Visit(that->on_success()); |
-} |
- |
- |
-void DotPrinter::VisitEnd(EndNode* that) { |
- os_ << " n" << that << " [style=bold, shape=point];\n"; |
- PrintAttributes(that); |
-} |
- |
- |
-void DotPrinter::VisitAssertion(AssertionNode* that) { |
- os_ << " n" << that << " ["; |
- switch (that->assertion_type()) { |
- case AssertionNode::AT_END: |
- os_ << "label=\"$\", shape=septagon"; |
- break; |
- case AssertionNode::AT_START: |
- os_ << "label=\"^\", shape=septagon"; |
- break; |
- case AssertionNode::AT_BOUNDARY: |
- os_ << "label=\"\\b\", shape=septagon"; |
- break; |
- case AssertionNode::AT_NON_BOUNDARY: |
- os_ << "label=\"\\B\", shape=septagon"; |
- break; |
- case AssertionNode::AFTER_NEWLINE: |
- os_ << "label=\"(?<=\\n)\", shape=septagon"; |
- break; |
- } |
- os_ << "];\n"; |
- PrintAttributes(that); |
- RegExpNode* successor = that->on_success(); |
- os_ << " n" << that << " -> n" << successor << ";\n"; |
- Visit(successor); |
-} |
- |
- |
-void DotPrinter::VisitAction(ActionNode* that) { |
- os_ << " n" << that << " ["; |
- switch (that->action_type_) { |
- case ActionNode::SET_REGISTER: |
- os_ << "label=\"$" << that->data_.u_store_register.reg |
- << ":=" << that->data_.u_store_register.value << "\", shape=octagon"; |
- break; |
- case ActionNode::INCREMENT_REGISTER: |
- os_ << "label=\"$" << that->data_.u_increment_register.reg |
- << "++\", shape=octagon"; |
- break; |
- case ActionNode::STORE_POSITION: |
- os_ << "label=\"$" << that->data_.u_position_register.reg |
- << ":=$pos\", shape=octagon"; |
- break; |
- case ActionNode::BEGIN_SUBMATCH: |
- os_ << "label=\"$" << that->data_.u_submatch.current_position_register |
- << ":=$pos,begin\", shape=septagon"; |
- break; |
- case ActionNode::POSITIVE_SUBMATCH_SUCCESS: |
- os_ << "label=\"escape\", shape=septagon"; |
- break; |
- case ActionNode::EMPTY_MATCH_CHECK: |
- os_ << "label=\"$" << that->data_.u_empty_match_check.start_register |
- << "=$pos?,$" << that->data_.u_empty_match_check.repetition_register |
- << "<" << that->data_.u_empty_match_check.repetition_limit |
- << "?\", shape=septagon"; |
- break; |
- case ActionNode::CLEAR_CAPTURES: { |
- os_ << "label=\"clear $" << that->data_.u_clear_captures.range_from |
- << " to $" << that->data_.u_clear_captures.range_to |
- << "\", shape=septagon"; |
- break; |
- } |
- } |
- os_ << "];\n"; |
- PrintAttributes(that); |
- RegExpNode* successor = that->on_success(); |
- os_ << " n" << that << " -> n" << successor << ";\n"; |
- Visit(successor); |
-} |
- |
- |
-class DispatchTableDumper { |
- public: |
- explicit DispatchTableDumper(std::ostream& os) : os_(os) {} |
- void Call(uc16 key, DispatchTable::Entry entry); |
- private: |
- std::ostream& os_; |
-}; |
- |
- |
-void DispatchTableDumper::Call(uc16 key, DispatchTable::Entry entry) { |
- os_ << "[" << AsUC16(key) << "-" << AsUC16(entry.to()) << "]: {"; |
- OutSet* set = entry.out_set(); |
- bool first = true; |
- for (unsigned i = 0; i < OutSet::kFirstLimit; i++) { |
- if (set->Get(i)) { |
- if (first) { |
- first = false; |
- } else { |
- os_ << ", "; |
- } |
- os_ << i; |
- } |
- } |
- os_ << "}\n"; |
-} |
- |
- |
-void DispatchTable::Dump() { |
- OFStream os(stderr); |
- DispatchTableDumper dumper(os); |
- tree()->ForEach(&dumper); |
-} |
- |
- |
-void RegExpEngine::DotPrint(const char* label, |
- RegExpNode* node, |
- bool ignore_case) { |
- OFStream os(stdout); |
- DotPrinter printer(os, ignore_case); |
- printer.PrintNode(label, node); |
-} |
- |
- |
-#endif // DEBUG |
- |
- |
-// ------------------------------------------------------------------- |
-// Tree to graph conversion |
- |
-RegExpNode* RegExpAtom::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- ZoneList<TextElement>* elms = |
- new(compiler->zone()) ZoneList<TextElement>(1, compiler->zone()); |
- elms->Add(TextElement::Atom(this), compiler->zone()); |
- return new(compiler->zone()) TextNode(elms, on_success); |
-} |
- |
- |
-RegExpNode* RegExpText::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return new(compiler->zone()) TextNode(elements(), on_success); |
-} |
- |
- |
-static bool CompareInverseRanges(ZoneList<CharacterRange>* ranges, |
- const int* special_class, |
- int length) { |
- length--; // Remove final 0x10000. |
- DCHECK(special_class[length] == 0x10000); |
- DCHECK(ranges->length() != 0); |
- DCHECK(length != 0); |
- DCHECK(special_class[0] != 0); |
- if (ranges->length() != (length >> 1) + 1) { |
- return false; |
- } |
- CharacterRange range = ranges->at(0); |
- if (range.from() != 0) { |
- return false; |
- } |
- for (int i = 0; i < length; i += 2) { |
- if (special_class[i] != (range.to() + 1)) { |
- return false; |
- } |
- range = ranges->at((i >> 1) + 1); |
- if (special_class[i+1] != range.from()) { |
- return false; |
- } |
- } |
- if (range.to() != 0xffff) { |
- return false; |
- } |
- return true; |
-} |
- |
- |
-static bool CompareRanges(ZoneList<CharacterRange>* ranges, |
- const int* special_class, |
- int length) { |
- length--; // Remove final 0x10000. |
- DCHECK(special_class[length] == 0x10000); |
- if (ranges->length() * 2 != length) { |
- return false; |
- } |
- for (int i = 0; i < length; i += 2) { |
- CharacterRange range = ranges->at(i >> 1); |
- if (range.from() != special_class[i] || |
- range.to() != special_class[i + 1] - 1) { |
- return false; |
- } |
- } |
- return true; |
-} |
- |
- |
-bool RegExpCharacterClass::is_standard(Zone* zone) { |
- // TODO(lrn): Remove need for this function, by not throwing away information |
- // along the way. |
- if (is_negated_) { |
- return false; |
- } |
- if (set_.is_standard()) { |
- return true; |
- } |
- if (CompareRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) { |
- set_.set_standard_set_type('s'); |
- return true; |
- } |
- if (CompareInverseRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) { |
- set_.set_standard_set_type('S'); |
- return true; |
- } |
- if (CompareInverseRanges(set_.ranges(zone), |
- kLineTerminatorRanges, |
- kLineTerminatorRangeCount)) { |
- set_.set_standard_set_type('.'); |
- return true; |
- } |
- if (CompareRanges(set_.ranges(zone), |
- kLineTerminatorRanges, |
- kLineTerminatorRangeCount)) { |
- set_.set_standard_set_type('n'); |
- return true; |
- } |
- if (CompareRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) { |
- set_.set_standard_set_type('w'); |
- return true; |
- } |
- if (CompareInverseRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) { |
- set_.set_standard_set_type('W'); |
- return true; |
- } |
- return false; |
-} |
- |
- |
-RegExpNode* RegExpCharacterClass::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return new(compiler->zone()) TextNode(this, on_success); |
-} |
- |
- |
-int CompareFirstChar(RegExpTree* const* a, RegExpTree* const* b) { |
- RegExpAtom* atom1 = (*a)->AsAtom(); |
- RegExpAtom* atom2 = (*b)->AsAtom(); |
- uc16 character1 = atom1->data().at(0); |
- uc16 character2 = atom2->data().at(0); |
- if (character1 < character2) return -1; |
- if (character1 > character2) return 1; |
- return 0; |
-} |
- |
- |
-static unibrow::uchar Canonical( |
- unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize, |
- unibrow::uchar c) { |
- unibrow::uchar chars[unibrow::Ecma262Canonicalize::kMaxWidth]; |
- int length = canonicalize->get(c, '\0', chars); |
- DCHECK_LE(length, 1); |
- unibrow::uchar canonical = c; |
- if (length == 1) canonical = chars[0]; |
- return canonical; |
-} |
- |
- |
-int CompareFirstCharCaseIndependent( |
- unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize, |
- RegExpTree* const* a, RegExpTree* const* b) { |
- RegExpAtom* atom1 = (*a)->AsAtom(); |
- RegExpAtom* atom2 = (*b)->AsAtom(); |
- unibrow::uchar character1 = atom1->data().at(0); |
- unibrow::uchar character2 = atom2->data().at(0); |
- if (character1 == character2) return 0; |
- if (character1 >= 'a' || character2 >= 'a') { |
- character1 = Canonical(canonicalize, character1); |
- character2 = Canonical(canonicalize, character2); |
- } |
- return static_cast<int>(character1) - static_cast<int>(character2); |
-} |
- |
- |
-// We can stable sort runs of atoms, since the order does not matter if they |
-// start with different characters. |
-// Returns true if any consecutive atoms were found. |
-bool RegExpDisjunction::SortConsecutiveAtoms(RegExpCompiler* compiler) { |
- ZoneList<RegExpTree*>* alternatives = this->alternatives(); |
- int length = alternatives->length(); |
- bool found_consecutive_atoms = false; |
- for (int i = 0; i < length; i++) { |
- while (i < length) { |
- RegExpTree* alternative = alternatives->at(i); |
- if (alternative->IsAtom()) break; |
- i++; |
- } |
- // i is length or it is the index of an atom. |
- if (i == length) break; |
- int first_atom = i; |
- i++; |
- while (i < length) { |
- RegExpTree* alternative = alternatives->at(i); |
- if (!alternative->IsAtom()) break; |
- i++; |
- } |
- // Sort atoms to get ones with common prefixes together. |
- // This step is more tricky if we are in a case-independent regexp, |
- // because it would change /is|I/ to /I|is/, and order matters when |
- // the regexp parts don't match only disjoint starting points. To fix |
- // this we have a version of CompareFirstChar that uses case- |
- // independent character classes for comparison. |
- DCHECK_LT(first_atom, alternatives->length()); |
- DCHECK_LE(i, alternatives->length()); |
- DCHECK_LE(first_atom, i); |
- if (compiler->ignore_case()) { |
- unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize = |
- compiler->isolate()->regexp_macro_assembler_canonicalize(); |
- auto compare_closure = |
- [canonicalize](RegExpTree* const* a, RegExpTree* const* b) { |
- return CompareFirstCharCaseIndependent(canonicalize, a, b); |
- }; |
- alternatives->StableSort(compare_closure, first_atom, i - first_atom); |
- } else { |
- alternatives->StableSort(CompareFirstChar, first_atom, i - first_atom); |
- } |
- if (i - first_atom > 1) found_consecutive_atoms = true; |
- } |
- return found_consecutive_atoms; |
-} |
- |
- |
-// Optimizes ab|ac|az to a(?:b|c|d). |
-void RegExpDisjunction::RationalizeConsecutiveAtoms(RegExpCompiler* compiler) { |
- Zone* zone = compiler->zone(); |
- ZoneList<RegExpTree*>* alternatives = this->alternatives(); |
- int length = alternatives->length(); |
- |
- int write_posn = 0; |
- int i = 0; |
- while (i < length) { |
- RegExpTree* alternative = alternatives->at(i); |
- if (!alternative->IsAtom()) { |
- alternatives->at(write_posn++) = alternatives->at(i); |
- i++; |
- continue; |
- } |
- RegExpAtom* atom = alternative->AsAtom(); |
- unibrow::uchar common_prefix = atom->data().at(0); |
- int first_with_prefix = i; |
- int prefix_length = atom->length(); |
- i++; |
- while (i < length) { |
- alternative = alternatives->at(i); |
- if (!alternative->IsAtom()) break; |
- atom = alternative->AsAtom(); |
- unibrow::uchar new_prefix = atom->data().at(0); |
- if (new_prefix != common_prefix) { |
- if (!compiler->ignore_case()) break; |
- unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize = |
- compiler->isolate()->regexp_macro_assembler_canonicalize(); |
- new_prefix = Canonical(canonicalize, new_prefix); |
- common_prefix = Canonical(canonicalize, common_prefix); |
- if (new_prefix != common_prefix) break; |
- } |
- prefix_length = Min(prefix_length, atom->length()); |
- i++; |
- } |
- if (i > first_with_prefix + 2) { |
- // Found worthwhile run of alternatives with common prefix of at least one |
- // character. The sorting function above did not sort on more than one |
- // character for reasons of correctness, but there may still be a longer |
- // common prefix if the terms were similar or presorted in the input. |
- // Find out how long the common prefix is. |
- int run_length = i - first_with_prefix; |
- atom = alternatives->at(first_with_prefix)->AsAtom(); |
- for (int j = 1; j < run_length && prefix_length > 1; j++) { |
- RegExpAtom* old_atom = |
- alternatives->at(j + first_with_prefix)->AsAtom(); |
- for (int k = 1; k < prefix_length; k++) { |
- if (atom->data().at(k) != old_atom->data().at(k)) { |
- prefix_length = k; |
- break; |
- } |
- } |
- } |
- RegExpAtom* prefix = |
- new (zone) RegExpAtom(atom->data().SubVector(0, prefix_length)); |
- ZoneList<RegExpTree*>* pair = new (zone) ZoneList<RegExpTree*>(2, zone); |
- pair->Add(prefix, zone); |
- ZoneList<RegExpTree*>* suffixes = |
- new (zone) ZoneList<RegExpTree*>(run_length, zone); |
- for (int j = 0; j < run_length; j++) { |
- RegExpAtom* old_atom = |
- alternatives->at(j + first_with_prefix)->AsAtom(); |
- int len = old_atom->length(); |
- if (len == prefix_length) { |
- suffixes->Add(new (zone) RegExpEmpty(), zone); |
- } else { |
- RegExpTree* suffix = new (zone) RegExpAtom( |
- old_atom->data().SubVector(prefix_length, old_atom->length())); |
- suffixes->Add(suffix, zone); |
- } |
- } |
- pair->Add(new (zone) RegExpDisjunction(suffixes), zone); |
- alternatives->at(write_posn++) = new (zone) RegExpAlternative(pair); |
- } else { |
- // Just copy any non-worthwhile alternatives. |
- for (int j = first_with_prefix; j < i; j++) { |
- alternatives->at(write_posn++) = alternatives->at(j); |
- } |
- } |
- } |
- alternatives->Rewind(write_posn); // Trim end of array. |
-} |
- |
- |
-// Optimizes b|c|z to [bcz]. |
-void RegExpDisjunction::FixSingleCharacterDisjunctions( |
- RegExpCompiler* compiler) { |
- Zone* zone = compiler->zone(); |
- ZoneList<RegExpTree*>* alternatives = this->alternatives(); |
- int length = alternatives->length(); |
- |
- int write_posn = 0; |
- int i = 0; |
- while (i < length) { |
- RegExpTree* alternative = alternatives->at(i); |
- if (!alternative->IsAtom()) { |
- alternatives->at(write_posn++) = alternatives->at(i); |
- i++; |
- continue; |
- } |
- RegExpAtom* atom = alternative->AsAtom(); |
- if (atom->length() != 1) { |
- alternatives->at(write_posn++) = alternatives->at(i); |
- i++; |
- continue; |
- } |
- int first_in_run = i; |
- i++; |
- while (i < length) { |
- alternative = alternatives->at(i); |
- if (!alternative->IsAtom()) break; |
- atom = alternative->AsAtom(); |
- if (atom->length() != 1) break; |
- i++; |
- } |
- if (i > first_in_run + 1) { |
- // Found non-trivial run of single-character alternatives. |
- int run_length = i - first_in_run; |
- ZoneList<CharacterRange>* ranges = |
- new (zone) ZoneList<CharacterRange>(2, zone); |
- for (int j = 0; j < run_length; j++) { |
- RegExpAtom* old_atom = alternatives->at(j + first_in_run)->AsAtom(); |
- DCHECK_EQ(old_atom->length(), 1); |
- ranges->Add(CharacterRange::Singleton(old_atom->data().at(0)), zone); |
- } |
- alternatives->at(write_posn++) = |
- new (zone) RegExpCharacterClass(ranges, false); |
- } else { |
- // Just copy any trivial alternatives. |
- for (int j = first_in_run; j < i; j++) { |
- alternatives->at(write_posn++) = alternatives->at(j); |
- } |
- } |
- } |
- alternatives->Rewind(write_posn); // Trim end of array. |
-} |
- |
- |
-RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- ZoneList<RegExpTree*>* alternatives = this->alternatives(); |
- |
- if (alternatives->length() > 2) { |
- bool found_consecutive_atoms = SortConsecutiveAtoms(compiler); |
- if (found_consecutive_atoms) RationalizeConsecutiveAtoms(compiler); |
- FixSingleCharacterDisjunctions(compiler); |
- if (alternatives->length() == 1) { |
- return alternatives->at(0)->ToNode(compiler, on_success); |
- } |
- } |
- |
- int length = alternatives->length(); |
- |
- ChoiceNode* result = |
- new(compiler->zone()) ChoiceNode(length, compiler->zone()); |
- for (int i = 0; i < length; i++) { |
- GuardedAlternative alternative(alternatives->at(i)->ToNode(compiler, |
- on_success)); |
- result->AddAlternative(alternative); |
- } |
- return result; |
-} |
- |
- |
-RegExpNode* RegExpQuantifier::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return ToNode(min(), |
- max(), |
- is_greedy(), |
- body(), |
- compiler, |
- on_success); |
-} |
- |
- |
-// Scoped object to keep track of how much we unroll quantifier loops in the |
-// regexp graph generator. |
-class RegExpExpansionLimiter { |
- public: |
- static const int kMaxExpansionFactor = 6; |
- RegExpExpansionLimiter(RegExpCompiler* compiler, int factor) |
- : compiler_(compiler), |
- saved_expansion_factor_(compiler->current_expansion_factor()), |
- ok_to_expand_(saved_expansion_factor_ <= kMaxExpansionFactor) { |
- DCHECK(factor > 0); |
- if (ok_to_expand_) { |
- if (factor > kMaxExpansionFactor) { |
- // Avoid integer overflow of the current expansion factor. |
- ok_to_expand_ = false; |
- compiler->set_current_expansion_factor(kMaxExpansionFactor + 1); |
- } else { |
- int new_factor = saved_expansion_factor_ * factor; |
- ok_to_expand_ = (new_factor <= kMaxExpansionFactor); |
- compiler->set_current_expansion_factor(new_factor); |
- } |
- } |
- } |
- |
- ~RegExpExpansionLimiter() { |
- compiler_->set_current_expansion_factor(saved_expansion_factor_); |
- } |
- |
- bool ok_to_expand() { return ok_to_expand_; } |
- |
- private: |
- RegExpCompiler* compiler_; |
- int saved_expansion_factor_; |
- bool ok_to_expand_; |
- |
- DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpExpansionLimiter); |
-}; |
- |
- |
-RegExpNode* RegExpQuantifier::ToNode(int min, |
- int max, |
- bool is_greedy, |
- RegExpTree* body, |
- RegExpCompiler* compiler, |
- RegExpNode* on_success, |
- bool not_at_start) { |
- // x{f, t} becomes this: |
- // |
- // (r++)<-. |
- // | ` |
- // | (x) |
- // v ^ |
- // (r=0)-->(?)---/ [if r < t] |
- // | |
- // [if r >= f] \----> ... |
- // |
- |
- // 15.10.2.5 RepeatMatcher algorithm. |
- // The parser has already eliminated the case where max is 0. In the case |
- // where max_match is zero the parser has removed the quantifier if min was |
- // > 0 and removed the atom if min was 0. See AddQuantifierToAtom. |
- |
- // If we know that we cannot match zero length then things are a little |
- // simpler since we don't need to make the special zero length match check |
- // from step 2.1. If the min and max are small we can unroll a little in |
- // this case. |
- static const int kMaxUnrolledMinMatches = 3; // Unroll (foo)+ and (foo){3,} |
- static const int kMaxUnrolledMaxMatches = 3; // Unroll (foo)? and (foo){x,3} |
- if (max == 0) return on_success; // This can happen due to recursion. |
- bool body_can_be_empty = (body->min_match() == 0); |
- int body_start_reg = RegExpCompiler::kNoRegister; |
- Interval capture_registers = body->CaptureRegisters(); |
- bool needs_capture_clearing = !capture_registers.is_empty(); |
- Zone* zone = compiler->zone(); |
- |
- if (body_can_be_empty) { |
- body_start_reg = compiler->AllocateRegister(); |
- } else if (compiler->optimize() && !needs_capture_clearing) { |
- // Only unroll if there are no captures and the body can't be |
- // empty. |
- { |
- RegExpExpansionLimiter limiter( |
- compiler, min + ((max != min) ? 1 : 0)); |
- if (min > 0 && min <= kMaxUnrolledMinMatches && limiter.ok_to_expand()) { |
- int new_max = (max == kInfinity) ? max : max - min; |
- // Recurse once to get the loop or optional matches after the fixed |
- // ones. |
- RegExpNode* answer = ToNode( |
- 0, new_max, is_greedy, body, compiler, on_success, true); |
- // Unroll the forced matches from 0 to min. This can cause chains of |
- // TextNodes (which the parser does not generate). These should be |
- // combined if it turns out they hinder good code generation. |
- for (int i = 0; i < min; i++) { |
- answer = body->ToNode(compiler, answer); |
- } |
- return answer; |
- } |
- } |
- if (max <= kMaxUnrolledMaxMatches && min == 0) { |
- DCHECK(max > 0); // Due to the 'if' above. |
- RegExpExpansionLimiter limiter(compiler, max); |
- if (limiter.ok_to_expand()) { |
- // Unroll the optional matches up to max. |
- RegExpNode* answer = on_success; |
- for (int i = 0; i < max; i++) { |
- ChoiceNode* alternation = new(zone) ChoiceNode(2, zone); |
- if (is_greedy) { |
- alternation->AddAlternative( |
- GuardedAlternative(body->ToNode(compiler, answer))); |
- alternation->AddAlternative(GuardedAlternative(on_success)); |
- } else { |
- alternation->AddAlternative(GuardedAlternative(on_success)); |
- alternation->AddAlternative( |
- GuardedAlternative(body->ToNode(compiler, answer))); |
- } |
- answer = alternation; |
- if (not_at_start) alternation->set_not_at_start(); |
- } |
- return answer; |
- } |
- } |
- } |
- bool has_min = min > 0; |
- bool has_max = max < RegExpTree::kInfinity; |
- bool needs_counter = has_min || has_max; |
- int reg_ctr = needs_counter |
- ? compiler->AllocateRegister() |
- : RegExpCompiler::kNoRegister; |
- LoopChoiceNode* center = new(zone) LoopChoiceNode(body->min_match() == 0, |
- zone); |
- if (not_at_start) center->set_not_at_start(); |
- RegExpNode* loop_return = needs_counter |
- ? static_cast<RegExpNode*>(ActionNode::IncrementRegister(reg_ctr, center)) |
- : static_cast<RegExpNode*>(center); |
- if (body_can_be_empty) { |
- // If the body can be empty we need to check if it was and then |
- // backtrack. |
- loop_return = ActionNode::EmptyMatchCheck(body_start_reg, |
- reg_ctr, |
- min, |
- loop_return); |
- } |
- RegExpNode* body_node = body->ToNode(compiler, loop_return); |
- if (body_can_be_empty) { |
- // If the body can be empty we need to store the start position |
- // so we can bail out if it was empty. |
- body_node = ActionNode::StorePosition(body_start_reg, false, body_node); |
- } |
- if (needs_capture_clearing) { |
- // Before entering the body of this loop we need to clear captures. |
- body_node = ActionNode::ClearCaptures(capture_registers, body_node); |
- } |
- GuardedAlternative body_alt(body_node); |
- if (has_max) { |
- Guard* body_guard = |
- new(zone) Guard(reg_ctr, Guard::LT, max); |
- body_alt.AddGuard(body_guard, zone); |
- } |
- GuardedAlternative rest_alt(on_success); |
- if (has_min) { |
- Guard* rest_guard = new(compiler->zone()) Guard(reg_ctr, Guard::GEQ, min); |
- rest_alt.AddGuard(rest_guard, zone); |
- } |
- if (is_greedy) { |
- center->AddLoopAlternative(body_alt); |
- center->AddContinueAlternative(rest_alt); |
- } else { |
- center->AddContinueAlternative(rest_alt); |
- center->AddLoopAlternative(body_alt); |
- } |
- if (needs_counter) { |
- return ActionNode::SetRegister(reg_ctr, 0, center); |
- } else { |
- return center; |
- } |
-} |
- |
- |
-RegExpNode* RegExpAssertion::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- NodeInfo info; |
- Zone* zone = compiler->zone(); |
- |
- switch (assertion_type()) { |
- case START_OF_LINE: |
- return AssertionNode::AfterNewline(on_success); |
- case START_OF_INPUT: |
- return AssertionNode::AtStart(on_success); |
- case BOUNDARY: |
- return AssertionNode::AtBoundary(on_success); |
- case NON_BOUNDARY: |
- return AssertionNode::AtNonBoundary(on_success); |
- case END_OF_INPUT: |
- return AssertionNode::AtEnd(on_success); |
- case END_OF_LINE: { |
- // Compile $ in multiline regexps as an alternation with a positive |
- // lookahead in one side and an end-of-input on the other side. |
- // We need two registers for the lookahead. |
- int stack_pointer_register = compiler->AllocateRegister(); |
- int position_register = compiler->AllocateRegister(); |
- // The ChoiceNode to distinguish between a newline and end-of-input. |
- ChoiceNode* result = new(zone) ChoiceNode(2, zone); |
- // Create a newline atom. |
- ZoneList<CharacterRange>* newline_ranges = |
- new(zone) ZoneList<CharacterRange>(3, zone); |
- CharacterRange::AddClassEscape('n', newline_ranges, zone); |
- RegExpCharacterClass* newline_atom = new(zone) RegExpCharacterClass('n'); |
- TextNode* newline_matcher = new(zone) TextNode( |
- newline_atom, |
- ActionNode::PositiveSubmatchSuccess(stack_pointer_register, |
- position_register, |
- 0, // No captures inside. |
- -1, // Ignored if no captures. |
- on_success)); |
- // Create an end-of-input matcher. |
- RegExpNode* end_of_line = ActionNode::BeginSubmatch( |
- stack_pointer_register, |
- position_register, |
- newline_matcher); |
- // Add the two alternatives to the ChoiceNode. |
- GuardedAlternative eol_alternative(end_of_line); |
- result->AddAlternative(eol_alternative); |
- GuardedAlternative end_alternative(AssertionNode::AtEnd(on_success)); |
- result->AddAlternative(end_alternative); |
- return result; |
- } |
- default: |
- UNREACHABLE(); |
- } |
- return on_success; |
-} |
- |
- |
-RegExpNode* RegExpBackReference::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return new(compiler->zone()) |
- BackReferenceNode(RegExpCapture::StartRegister(index()), |
- RegExpCapture::EndRegister(index()), |
- on_success); |
-} |
- |
- |
-RegExpNode* RegExpEmpty::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return on_success; |
-} |
- |
- |
-RegExpNode* RegExpLookahead::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- int stack_pointer_register = compiler->AllocateRegister(); |
- int position_register = compiler->AllocateRegister(); |
- |
- const int registers_per_capture = 2; |
- const int register_of_first_capture = 2; |
- int register_count = capture_count_ * registers_per_capture; |
- int register_start = |
- register_of_first_capture + capture_from_ * registers_per_capture; |
- |
- RegExpNode* success; |
- if (is_positive()) { |
- RegExpNode* node = ActionNode::BeginSubmatch( |
- stack_pointer_register, |
- position_register, |
- body()->ToNode( |
- compiler, |
- ActionNode::PositiveSubmatchSuccess(stack_pointer_register, |
- position_register, |
- register_count, |
- register_start, |
- on_success))); |
- return node; |
- } else { |
- // We use a ChoiceNode for a negative lookahead because it has most of |
- // the characteristics we need. It has the body of the lookahead as its |
- // first alternative and the expression after the lookahead of the second |
- // alternative. If the first alternative succeeds then the |
- // NegativeSubmatchSuccess will unwind the stack including everything the |
- // choice node set up and backtrack. If the first alternative fails then |
- // the second alternative is tried, which is exactly the desired result |
- // for a negative lookahead. The NegativeLookaheadChoiceNode is a special |
- // ChoiceNode that knows to ignore the first exit when calculating quick |
- // checks. |
- Zone* zone = compiler->zone(); |
- |
- GuardedAlternative body_alt( |
- body()->ToNode( |
- compiler, |
- success = new(zone) NegativeSubmatchSuccess(stack_pointer_register, |
- position_register, |
- register_count, |
- register_start, |
- zone))); |
- ChoiceNode* choice_node = |
- new(zone) NegativeLookaheadChoiceNode(body_alt, |
- GuardedAlternative(on_success), |
- zone); |
- return ActionNode::BeginSubmatch(stack_pointer_register, |
- position_register, |
- choice_node); |
- } |
-} |
- |
- |
-RegExpNode* RegExpCapture::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- return ToNode(body(), index(), compiler, on_success); |
-} |
- |
- |
-RegExpNode* RegExpCapture::ToNode(RegExpTree* body, |
- int index, |
- RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- int start_reg = RegExpCapture::StartRegister(index); |
- int end_reg = RegExpCapture::EndRegister(index); |
- RegExpNode* store_end = ActionNode::StorePosition(end_reg, true, on_success); |
- RegExpNode* body_node = body->ToNode(compiler, store_end); |
- return ActionNode::StorePosition(start_reg, true, body_node); |
-} |
- |
- |
-RegExpNode* RegExpAlternative::ToNode(RegExpCompiler* compiler, |
- RegExpNode* on_success) { |
- ZoneList<RegExpTree*>* children = nodes(); |
- RegExpNode* current = on_success; |
- for (int i = children->length() - 1; i >= 0; i--) { |
- current = children->at(i)->ToNode(compiler, current); |
- } |
- return current; |
-} |
- |
- |
-static void AddClass(const int* elmv, |
- int elmc, |
- ZoneList<CharacterRange>* ranges, |
- Zone* zone) { |
- elmc--; |
- DCHECK(elmv[elmc] == 0x10000); |
- for (int i = 0; i < elmc; i += 2) { |
- DCHECK(elmv[i] < elmv[i + 1]); |
- ranges->Add(CharacterRange(elmv[i], elmv[i + 1] - 1), zone); |
- } |
-} |
- |
- |
-static void AddClassNegated(const int *elmv, |
- int elmc, |
- ZoneList<CharacterRange>* ranges, |
- Zone* zone) { |
- elmc--; |
- DCHECK(elmv[elmc] == 0x10000); |
- DCHECK(elmv[0] != 0x0000); |
- DCHECK(elmv[elmc-1] != String::kMaxUtf16CodeUnit); |
- uc16 last = 0x0000; |
- for (int i = 0; i < elmc; i += 2) { |
- DCHECK(last <= elmv[i] - 1); |
- DCHECK(elmv[i] < elmv[i + 1]); |
- ranges->Add(CharacterRange(last, elmv[i] - 1), zone); |
- last = elmv[i + 1]; |
- } |
- ranges->Add(CharacterRange(last, String::kMaxUtf16CodeUnit), zone); |
-} |
- |
- |
-void CharacterRange::AddClassEscape(uc16 type, |
- ZoneList<CharacterRange>* ranges, |
- Zone* zone) { |
- switch (type) { |
- case 's': |
- AddClass(kSpaceRanges, kSpaceRangeCount, ranges, zone); |
- break; |
- case 'S': |
- AddClassNegated(kSpaceRanges, kSpaceRangeCount, ranges, zone); |
- break; |
- case 'w': |
- AddClass(kWordRanges, kWordRangeCount, ranges, zone); |
- break; |
- case 'W': |
- AddClassNegated(kWordRanges, kWordRangeCount, ranges, zone); |
- break; |
- case 'd': |
- AddClass(kDigitRanges, kDigitRangeCount, ranges, zone); |
- break; |
- case 'D': |
- AddClassNegated(kDigitRanges, kDigitRangeCount, ranges, zone); |
- break; |
- case '.': |
- AddClassNegated(kLineTerminatorRanges, |
- kLineTerminatorRangeCount, |
- ranges, |
- zone); |
- break; |
- // This is not a character range as defined by the spec but a |
- // convenient shorthand for a character class that matches any |
- // character. |
- case '*': |
- ranges->Add(CharacterRange::Everything(), zone); |
- break; |
- // This is the set of characters matched by the $ and ^ symbols |
- // in multiline mode. |
- case 'n': |
- AddClass(kLineTerminatorRanges, |
- kLineTerminatorRangeCount, |
- ranges, |
- zone); |
- break; |
- default: |
- UNREACHABLE(); |
- } |
-} |
- |
- |
-Vector<const int> CharacterRange::GetWordBounds() { |
- return Vector<const int>(kWordRanges, kWordRangeCount - 1); |
-} |
- |
- |
-class CharacterRangeSplitter { |
- public: |
- CharacterRangeSplitter(ZoneList<CharacterRange>** included, |
- ZoneList<CharacterRange>** excluded, |
- Zone* zone) |
- : included_(included), |
- excluded_(excluded), |
- zone_(zone) { } |
- void Call(uc16 from, DispatchTable::Entry entry); |
- |
- static const int kInBase = 0; |
- static const int kInOverlay = 1; |
- |
- private: |
- ZoneList<CharacterRange>** included_; |
- ZoneList<CharacterRange>** excluded_; |
- Zone* zone_; |
-}; |
- |
- |
-void CharacterRangeSplitter::Call(uc16 from, DispatchTable::Entry entry) { |
- if (!entry.out_set()->Get(kInBase)) return; |
- ZoneList<CharacterRange>** target = entry.out_set()->Get(kInOverlay) |
- ? included_ |
- : excluded_; |
- if (*target == NULL) *target = new(zone_) ZoneList<CharacterRange>(2, zone_); |
- (*target)->Add(CharacterRange(entry.from(), entry.to()), zone_); |
-} |
- |
- |
-void CharacterRange::Split(ZoneList<CharacterRange>* base, |
- Vector<const int> overlay, |
- ZoneList<CharacterRange>** included, |
- ZoneList<CharacterRange>** excluded, |
- Zone* zone) { |
- DCHECK_NULL(*included); |
- DCHECK_NULL(*excluded); |
- DispatchTable table(zone); |
- for (int i = 0; i < base->length(); i++) |
- table.AddRange(base->at(i), CharacterRangeSplitter::kInBase, zone); |
- for (int i = 0; i < overlay.length(); i += 2) { |
- table.AddRange(CharacterRange(overlay[i], overlay[i + 1] - 1), |
- CharacterRangeSplitter::kInOverlay, zone); |
- } |
- CharacterRangeSplitter callback(included, excluded, zone); |
- table.ForEach(&callback); |
-} |
- |
- |
-void CharacterRange::AddCaseEquivalents(Isolate* isolate, Zone* zone, |
- ZoneList<CharacterRange>* ranges, |
- bool is_one_byte) { |
- uc16 bottom = from(); |
- uc16 top = to(); |
- if (is_one_byte && !RangeContainsLatin1Equivalents(*this)) { |
- if (bottom > String::kMaxOneByteCharCode) return; |
- if (top > String::kMaxOneByteCharCode) top = String::kMaxOneByteCharCode; |
- } |
- unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- if (top == bottom) { |
- // If this is a singleton we just expand the one character. |
- int length = isolate->jsregexp_uncanonicalize()->get(bottom, '\0', chars); |
- for (int i = 0; i < length; i++) { |
- uc32 chr = chars[i]; |
- if (chr != bottom) { |
- ranges->Add(CharacterRange::Singleton(chars[i]), zone); |
- } |
- } |
- } else { |
- // If this is a range we expand the characters block by block, |
- // expanding contiguous subranges (blocks) one at a time. |
- // The approach is as follows. For a given start character we |
- // look up the remainder of the block that contains it (represented |
- // by the end point), for instance we find 'z' if the character |
- // is 'c'. A block is characterized by the property |
- // that all characters uncanonicalize in the same way, except that |
- // each entry in the result is incremented by the distance from the first |
- // element. So a-z is a block because 'a' uncanonicalizes to ['a', 'A'] and |
- // the k'th letter uncanonicalizes to ['a' + k, 'A' + k]. |
- // Once we've found the end point we look up its uncanonicalization |
- // and produce a range for each element. For instance for [c-f] |
- // we look up ['z', 'Z'] and produce [c-f] and [C-F]. We then only |
- // add a range if it is not already contained in the input, so [c-f] |
- // will be skipped but [C-F] will be added. If this range is not |
- // completely contained in a block we do this for all the blocks |
- // covered by the range (handling characters that is not in a block |
- // as a "singleton block"). |
- unibrow::uchar range[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- int pos = bottom; |
- while (pos <= top) { |
- int length = isolate->jsregexp_canonrange()->get(pos, '\0', range); |
- uc16 block_end; |
- if (length == 0) { |
- block_end = pos; |
- } else { |
- DCHECK_EQ(1, length); |
- block_end = range[0]; |
- } |
- int end = (block_end > top) ? top : block_end; |
- length = isolate->jsregexp_uncanonicalize()->get(block_end, '\0', range); |
- for (int i = 0; i < length; i++) { |
- uc32 c = range[i]; |
- uc16 range_from = c - (block_end - pos); |
- uc16 range_to = c - (block_end - end); |
- if (!(bottom <= range_from && range_to <= top)) { |
- ranges->Add(CharacterRange(range_from, range_to), zone); |
- } |
- } |
- pos = end + 1; |
- } |
- } |
-} |
- |
- |
-bool CharacterRange::IsCanonical(ZoneList<CharacterRange>* ranges) { |
- DCHECK_NOT_NULL(ranges); |
- int n = ranges->length(); |
- if (n <= 1) return true; |
- int max = ranges->at(0).to(); |
- for (int i = 1; i < n; i++) { |
- CharacterRange next_range = ranges->at(i); |
- if (next_range.from() <= max + 1) return false; |
- max = next_range.to(); |
- } |
- return true; |
-} |
- |
- |
-ZoneList<CharacterRange>* CharacterSet::ranges(Zone* zone) { |
- if (ranges_ == NULL) { |
- ranges_ = new(zone) ZoneList<CharacterRange>(2, zone); |
- CharacterRange::AddClassEscape(standard_set_type_, ranges_, zone); |
- } |
- return ranges_; |
-} |
- |
- |
-// Move a number of elements in a zonelist to another position |
-// in the same list. Handles overlapping source and target areas. |
-static void MoveRanges(ZoneList<CharacterRange>* list, |
- int from, |
- int to, |
- int count) { |
- // Ranges are potentially overlapping. |
- if (from < to) { |
- for (int i = count - 1; i >= 0; i--) { |
- list->at(to + i) = list->at(from + i); |
- } |
- } else { |
- for (int i = 0; i < count; i++) { |
- list->at(to + i) = list->at(from + i); |
- } |
- } |
-} |
- |
- |
-static int InsertRangeInCanonicalList(ZoneList<CharacterRange>* list, |
- int count, |
- CharacterRange insert) { |
- // Inserts a range into list[0..count[, which must be sorted |
- // by from value and non-overlapping and non-adjacent, using at most |
- // list[0..count] for the result. Returns the number of resulting |
- // canonicalized ranges. Inserting a range may collapse existing ranges into |
- // fewer ranges, so the return value can be anything in the range 1..count+1. |
- uc16 from = insert.from(); |
- uc16 to = insert.to(); |
- int start_pos = 0; |
- int end_pos = count; |
- for (int i = count - 1; i >= 0; i--) { |
- CharacterRange current = list->at(i); |
- if (current.from() > to + 1) { |
- end_pos = i; |
- } else if (current.to() + 1 < from) { |
- start_pos = i + 1; |
- break; |
- } |
- } |
- |
- // Inserted range overlaps, or is adjacent to, ranges at positions |
- // [start_pos..end_pos[. Ranges before start_pos or at or after end_pos are |
- // not affected by the insertion. |
- // If start_pos == end_pos, the range must be inserted before start_pos. |
- // if start_pos < end_pos, the entire range from start_pos to end_pos |
- // must be merged with the insert range. |
- |
- if (start_pos == end_pos) { |
- // Insert between existing ranges at position start_pos. |
- if (start_pos < count) { |
- MoveRanges(list, start_pos, start_pos + 1, count - start_pos); |
- } |
- list->at(start_pos) = insert; |
- return count + 1; |
- } |
- if (start_pos + 1 == end_pos) { |
- // Replace single existing range at position start_pos. |
- CharacterRange to_replace = list->at(start_pos); |
- int new_from = Min(to_replace.from(), from); |
- int new_to = Max(to_replace.to(), to); |
- list->at(start_pos) = CharacterRange(new_from, new_to); |
- return count; |
- } |
- // Replace a number of existing ranges from start_pos to end_pos - 1. |
- // Move the remaining ranges down. |
- |
- int new_from = Min(list->at(start_pos).from(), from); |
- int new_to = Max(list->at(end_pos - 1).to(), to); |
- if (end_pos < count) { |
- MoveRanges(list, end_pos, start_pos + 1, count - end_pos); |
- } |
- list->at(start_pos) = CharacterRange(new_from, new_to); |
- return count - (end_pos - start_pos) + 1; |
-} |
- |
- |
-void CharacterSet::Canonicalize() { |
- // Special/default classes are always considered canonical. The result |
- // of calling ranges() will be sorted. |
- if (ranges_ == NULL) return; |
- CharacterRange::Canonicalize(ranges_); |
-} |
- |
- |
-void CharacterRange::Canonicalize(ZoneList<CharacterRange>* character_ranges) { |
- if (character_ranges->length() <= 1) return; |
- // Check whether ranges are already canonical (increasing, non-overlapping, |
- // non-adjacent). |
- int n = character_ranges->length(); |
- int max = character_ranges->at(0).to(); |
- int i = 1; |
- while (i < n) { |
- CharacterRange current = character_ranges->at(i); |
- if (current.from() <= max + 1) { |
- break; |
- } |
- max = current.to(); |
- i++; |
- } |
- // Canonical until the i'th range. If that's all of them, we are done. |
- if (i == n) return; |
- |
- // The ranges at index i and forward are not canonicalized. Make them so by |
- // doing the equivalent of insertion sort (inserting each into the previous |
- // list, in order). |
- // Notice that inserting a range can reduce the number of ranges in the |
- // result due to combining of adjacent and overlapping ranges. |
- int read = i; // Range to insert. |
- int num_canonical = i; // Length of canonicalized part of list. |
- do { |
- num_canonical = InsertRangeInCanonicalList(character_ranges, |
- num_canonical, |
- character_ranges->at(read)); |
- read++; |
- } while (read < n); |
- character_ranges->Rewind(num_canonical); |
- |
- DCHECK(CharacterRange::IsCanonical(character_ranges)); |
-} |
- |
- |
-void CharacterRange::Negate(ZoneList<CharacterRange>* ranges, |
- ZoneList<CharacterRange>* negated_ranges, |
- Zone* zone) { |
- DCHECK(CharacterRange::IsCanonical(ranges)); |
- DCHECK_EQ(0, negated_ranges->length()); |
- int range_count = ranges->length(); |
- uc16 from = 0; |
- int i = 0; |
- if (range_count > 0 && ranges->at(0).from() == 0) { |
- from = ranges->at(0).to(); |
- i = 1; |
- } |
- while (i < range_count) { |
- CharacterRange range = ranges->at(i); |
- negated_ranges->Add(CharacterRange(from + 1, range.from() - 1), zone); |
- from = range.to(); |
- i++; |
- } |
- if (from < String::kMaxUtf16CodeUnit) { |
- negated_ranges->Add(CharacterRange(from + 1, String::kMaxUtf16CodeUnit), |
- zone); |
- } |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Splay tree |
- |
- |
-OutSet* OutSet::Extend(unsigned value, Zone* zone) { |
- if (Get(value)) |
- return this; |
- if (successors(zone) != NULL) { |
- for (int i = 0; i < successors(zone)->length(); i++) { |
- OutSet* successor = successors(zone)->at(i); |
- if (successor->Get(value)) |
- return successor; |
- } |
- } else { |
- successors_ = new(zone) ZoneList<OutSet*>(2, zone); |
- } |
- OutSet* result = new(zone) OutSet(first_, remaining_); |
- result->Set(value, zone); |
- successors(zone)->Add(result, zone); |
- return result; |
-} |
- |
- |
-void OutSet::Set(unsigned value, Zone *zone) { |
- if (value < kFirstLimit) { |
- first_ |= (1 << value); |
- } else { |
- if (remaining_ == NULL) |
- remaining_ = new(zone) ZoneList<unsigned>(1, zone); |
- if (remaining_->is_empty() || !remaining_->Contains(value)) |
- remaining_->Add(value, zone); |
- } |
-} |
- |
- |
-bool OutSet::Get(unsigned value) const { |
- if (value < kFirstLimit) { |
- return (first_ & (1 << value)) != 0; |
- } else if (remaining_ == NULL) { |
- return false; |
- } else { |
- return remaining_->Contains(value); |
- } |
-} |
- |
- |
-const uc16 DispatchTable::Config::kNoKey = unibrow::Utf8::kBadChar; |
- |
- |
-void DispatchTable::AddRange(CharacterRange full_range, int value, |
- Zone* zone) { |
- CharacterRange current = full_range; |
- if (tree()->is_empty()) { |
- // If this is the first range we just insert into the table. |
- ZoneSplayTree<Config>::Locator loc; |
- bool inserted = tree()->Insert(current.from(), &loc); |
- DCHECK(inserted); |
- USE(inserted); |
- loc.set_value(Entry(current.from(), current.to(), |
- empty()->Extend(value, zone))); |
- return; |
- } |
- // First see if there is a range to the left of this one that |
- // overlaps. |
- ZoneSplayTree<Config>::Locator loc; |
- if (tree()->FindGreatestLessThan(current.from(), &loc)) { |
- Entry* entry = &loc.value(); |
- // If we've found a range that overlaps with this one, and it |
- // starts strictly to the left of this one, we have to fix it |
- // because the following code only handles ranges that start on |
- // or after the start point of the range we're adding. |
- if (entry->from() < current.from() && entry->to() >= current.from()) { |
- // Snap the overlapping range in half around the start point of |
- // the range we're adding. |
- CharacterRange left(entry->from(), current.from() - 1); |
- CharacterRange right(current.from(), entry->to()); |
- // The left part of the overlapping range doesn't overlap. |
- // Truncate the whole entry to be just the left part. |
- entry->set_to(left.to()); |
- // The right part is the one that overlaps. We add this part |
- // to the map and let the next step deal with merging it with |
- // the range we're adding. |
- ZoneSplayTree<Config>::Locator loc; |
- bool inserted = tree()->Insert(right.from(), &loc); |
- DCHECK(inserted); |
- USE(inserted); |
- loc.set_value(Entry(right.from(), |
- right.to(), |
- entry->out_set())); |
- } |
- } |
- while (current.is_valid()) { |
- if (tree()->FindLeastGreaterThan(current.from(), &loc) && |
- (loc.value().from() <= current.to()) && |
- (loc.value().to() >= current.from())) { |
- Entry* entry = &loc.value(); |
- // We have overlap. If there is space between the start point of |
- // the range we're adding and where the overlapping range starts |
- // then we have to add a range covering just that space. |
- if (current.from() < entry->from()) { |
- ZoneSplayTree<Config>::Locator ins; |
- bool inserted = tree()->Insert(current.from(), &ins); |
- DCHECK(inserted); |
- USE(inserted); |
- ins.set_value(Entry(current.from(), |
- entry->from() - 1, |
- empty()->Extend(value, zone))); |
- current.set_from(entry->from()); |
- } |
- DCHECK_EQ(current.from(), entry->from()); |
- // If the overlapping range extends beyond the one we want to add |
- // we have to snap the right part off and add it separately. |
- if (entry->to() > current.to()) { |
- ZoneSplayTree<Config>::Locator ins; |
- bool inserted = tree()->Insert(current.to() + 1, &ins); |
- DCHECK(inserted); |
- USE(inserted); |
- ins.set_value(Entry(current.to() + 1, |
- entry->to(), |
- entry->out_set())); |
- entry->set_to(current.to()); |
- } |
- DCHECK(entry->to() <= current.to()); |
- // The overlapping range is now completely contained by the range |
- // we're adding so we can just update it and move the start point |
- // of the range we're adding just past it. |
- entry->AddValue(value, zone); |
- // Bail out if the last interval ended at 0xFFFF since otherwise |
- // adding 1 will wrap around to 0. |
- if (entry->to() == String::kMaxUtf16CodeUnit) |
- break; |
- DCHECK(entry->to() + 1 > current.from()); |
- current.set_from(entry->to() + 1); |
- } else { |
- // There is no overlap so we can just add the range |
- ZoneSplayTree<Config>::Locator ins; |
- bool inserted = tree()->Insert(current.from(), &ins); |
- DCHECK(inserted); |
- USE(inserted); |
- ins.set_value(Entry(current.from(), |
- current.to(), |
- empty()->Extend(value, zone))); |
- break; |
- } |
- } |
-} |
- |
- |
-OutSet* DispatchTable::Get(uc16 value) { |
- ZoneSplayTree<Config>::Locator loc; |
- if (!tree()->FindGreatestLessThan(value, &loc)) |
- return empty(); |
- Entry* entry = &loc.value(); |
- if (value <= entry->to()) |
- return entry->out_set(); |
- else |
- return empty(); |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Analysis |
- |
- |
-void Analysis::EnsureAnalyzed(RegExpNode* that) { |
- StackLimitCheck check(isolate()); |
- if (check.HasOverflowed()) { |
- fail("Stack overflow"); |
- return; |
- } |
- if (that->info()->been_analyzed || that->info()->being_analyzed) |
- return; |
- that->info()->being_analyzed = true; |
- that->Accept(this); |
- that->info()->being_analyzed = false; |
- that->info()->been_analyzed = true; |
-} |
- |
- |
-void Analysis::VisitEnd(EndNode* that) { |
- // nothing to do |
-} |
- |
- |
-void TextNode::CalculateOffsets() { |
- int element_count = elements()->length(); |
- // Set up the offsets of the elements relative to the start. This is a fixed |
- // quantity since a TextNode can only contain fixed-width things. |
- int cp_offset = 0; |
- for (int i = 0; i < element_count; i++) { |
- TextElement& elm = elements()->at(i); |
- elm.set_cp_offset(cp_offset); |
- cp_offset += elm.length(); |
- } |
-} |
- |
- |
-void Analysis::VisitText(TextNode* that) { |
- if (ignore_case_) { |
- that->MakeCaseIndependent(isolate(), is_one_byte_); |
- } |
- EnsureAnalyzed(that->on_success()); |
- if (!has_failed()) { |
- that->CalculateOffsets(); |
- } |
-} |
- |
- |
-void Analysis::VisitAction(ActionNode* that) { |
- RegExpNode* target = that->on_success(); |
- EnsureAnalyzed(target); |
- if (!has_failed()) { |
- // If the next node is interested in what it follows then this node |
- // has to be interested too so it can pass the information on. |
- that->info()->AddFromFollowing(target->info()); |
- } |
-} |
- |
- |
-void Analysis::VisitChoice(ChoiceNode* that) { |
- NodeInfo* info = that->info(); |
- for (int i = 0; i < that->alternatives()->length(); i++) { |
- RegExpNode* node = that->alternatives()->at(i).node(); |
- EnsureAnalyzed(node); |
- if (has_failed()) return; |
- // Anything the following nodes need to know has to be known by |
- // this node also, so it can pass it on. |
- info->AddFromFollowing(node->info()); |
- } |
-} |
- |
- |
-void Analysis::VisitLoopChoice(LoopChoiceNode* that) { |
- NodeInfo* info = that->info(); |
- for (int i = 0; i < that->alternatives()->length(); i++) { |
- RegExpNode* node = that->alternatives()->at(i).node(); |
- if (node != that->loop_node()) { |
- EnsureAnalyzed(node); |
- if (has_failed()) return; |
- info->AddFromFollowing(node->info()); |
- } |
- } |
- // Check the loop last since it may need the value of this node |
- // to get a correct result. |
- EnsureAnalyzed(that->loop_node()); |
- if (!has_failed()) { |
- info->AddFromFollowing(that->loop_node()->info()); |
- } |
-} |
- |
- |
-void Analysis::VisitBackReference(BackReferenceNode* that) { |
- EnsureAnalyzed(that->on_success()); |
-} |
- |
- |
-void Analysis::VisitAssertion(AssertionNode* that) { |
- EnsureAnalyzed(that->on_success()); |
-} |
- |
- |
-void BackReferenceNode::FillInBMInfo(Isolate* isolate, int offset, int budget, |
- BoyerMooreLookahead* bm, |
- bool not_at_start) { |
- // Working out the set of characters that a backreference can match is too |
- // hard, so we just say that any character can match. |
- bm->SetRest(offset); |
- SaveBMInfo(bm, not_at_start, offset); |
-} |
- |
- |
-STATIC_ASSERT(BoyerMoorePositionInfo::kMapSize == |
- RegExpMacroAssembler::kTableSize); |
- |
- |
-void ChoiceNode::FillInBMInfo(Isolate* isolate, int offset, int budget, |
- BoyerMooreLookahead* bm, bool not_at_start) { |
- ZoneList<GuardedAlternative>* alts = alternatives(); |
- budget = (budget - 1) / alts->length(); |
- for (int i = 0; i < alts->length(); i++) { |
- GuardedAlternative& alt = alts->at(i); |
- if (alt.guards() != NULL && alt.guards()->length() != 0) { |
- bm->SetRest(offset); // Give up trying to fill in info. |
- SaveBMInfo(bm, not_at_start, offset); |
- return; |
- } |
- alt.node()->FillInBMInfo(isolate, offset, budget, bm, not_at_start); |
- } |
- SaveBMInfo(bm, not_at_start, offset); |
-} |
- |
- |
-void TextNode::FillInBMInfo(Isolate* isolate, int initial_offset, int budget, |
- BoyerMooreLookahead* bm, bool not_at_start) { |
- if (initial_offset >= bm->length()) return; |
- int offset = initial_offset; |
- int max_char = bm->max_char(); |
- for (int i = 0; i < elements()->length(); i++) { |
- if (offset >= bm->length()) { |
- if (initial_offset == 0) set_bm_info(not_at_start, bm); |
- return; |
- } |
- TextElement text = elements()->at(i); |
- if (text.text_type() == TextElement::ATOM) { |
- RegExpAtom* atom = text.atom(); |
- for (int j = 0; j < atom->length(); j++, offset++) { |
- if (offset >= bm->length()) { |
- if (initial_offset == 0) set_bm_info(not_at_start, bm); |
- return; |
- } |
- uc16 character = atom->data()[j]; |
- if (bm->compiler()->ignore_case()) { |
- unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
- int length = GetCaseIndependentLetters( |
- isolate, character, bm->max_char() == String::kMaxOneByteCharCode, |
- chars); |
- for (int j = 0; j < length; j++) { |
- bm->Set(offset, chars[j]); |
- } |
- } else { |
- if (character <= max_char) bm->Set(offset, character); |
- } |
- } |
- } else { |
- DCHECK_EQ(TextElement::CHAR_CLASS, text.text_type()); |
- RegExpCharacterClass* char_class = text.char_class(); |
- ZoneList<CharacterRange>* ranges = char_class->ranges(zone()); |
- if (char_class->is_negated()) { |
- bm->SetAll(offset); |
- } else { |
- for (int k = 0; k < ranges->length(); k++) { |
- CharacterRange& range = ranges->at(k); |
- if (range.from() > max_char) continue; |
- int to = Min(max_char, static_cast<int>(range.to())); |
- bm->SetInterval(offset, Interval(range.from(), to)); |
- } |
- } |
- offset++; |
- } |
- } |
- if (offset >= bm->length()) { |
- if (initial_offset == 0) set_bm_info(not_at_start, bm); |
- return; |
- } |
- on_success()->FillInBMInfo(isolate, offset, budget - 1, bm, |
- true); // Not at start after a text node. |
- if (initial_offset == 0) set_bm_info(not_at_start, bm); |
-} |
- |
- |
-// ------------------------------------------------------------------- |
-// Dispatch table construction |
- |
- |
-void DispatchTableConstructor::VisitEnd(EndNode* that) { |
- AddRange(CharacterRange::Everything()); |
-} |
- |
- |
-void DispatchTableConstructor::BuildTable(ChoiceNode* node) { |
- node->set_being_calculated(true); |
- ZoneList<GuardedAlternative>* alternatives = node->alternatives(); |
- for (int i = 0; i < alternatives->length(); i++) { |
- set_choice_index(i); |
- alternatives->at(i).node()->Accept(this); |
- } |
- node->set_being_calculated(false); |
-} |
- |
- |
-class AddDispatchRange { |
- public: |
- explicit AddDispatchRange(DispatchTableConstructor* constructor) |
- : constructor_(constructor) { } |
- void Call(uc32 from, DispatchTable::Entry entry); |
- private: |
- DispatchTableConstructor* constructor_; |
-}; |
- |
- |
-void AddDispatchRange::Call(uc32 from, DispatchTable::Entry entry) { |
- CharacterRange range(from, entry.to()); |
- constructor_->AddRange(range); |
-} |
- |
- |
-void DispatchTableConstructor::VisitChoice(ChoiceNode* node) { |
- if (node->being_calculated()) |
- return; |
- DispatchTable* table = node->GetTable(ignore_case_); |
- AddDispatchRange adder(this); |
- table->ForEach(&adder); |
-} |
- |
- |
-void DispatchTableConstructor::VisitBackReference(BackReferenceNode* that) { |
- // TODO(160): Find the node that we refer back to and propagate its start |
- // set back to here. For now we just accept anything. |
- AddRange(CharacterRange::Everything()); |
-} |
- |
- |
-void DispatchTableConstructor::VisitAssertion(AssertionNode* that) { |
- RegExpNode* target = that->on_success(); |
- target->Accept(this); |
-} |
- |
- |
-static int CompareRangeByFrom(const CharacterRange* a, |
- const CharacterRange* b) { |
- return Compare<uc16>(a->from(), b->from()); |
-} |
- |
- |
-void DispatchTableConstructor::AddInverse(ZoneList<CharacterRange>* ranges) { |
- ranges->Sort(CompareRangeByFrom); |
- uc16 last = 0; |
- for (int i = 0; i < ranges->length(); i++) { |
- CharacterRange range = ranges->at(i); |
- if (last < range.from()) |
- AddRange(CharacterRange(last, range.from() - 1)); |
- if (range.to() >= last) { |
- if (range.to() == String::kMaxUtf16CodeUnit) { |
- return; |
- } else { |
- last = range.to() + 1; |
- } |
- } |
- } |
- AddRange(CharacterRange(last, String::kMaxUtf16CodeUnit)); |
-} |
- |
- |
-void DispatchTableConstructor::VisitText(TextNode* that) { |
- TextElement elm = that->elements()->at(0); |
- switch (elm.text_type()) { |
- case TextElement::ATOM: { |
- uc16 c = elm.atom()->data()[0]; |
- AddRange(CharacterRange(c, c)); |
- break; |
- } |
- case TextElement::CHAR_CLASS: { |
- RegExpCharacterClass* tree = elm.char_class(); |
- ZoneList<CharacterRange>* ranges = tree->ranges(that->zone()); |
- if (tree->is_negated()) { |
- AddInverse(ranges); |
- } else { |
- for (int i = 0; i < ranges->length(); i++) |
- AddRange(ranges->at(i)); |
- } |
- break; |
- } |
- default: { |
- UNIMPLEMENTED(); |
- } |
- } |
-} |
- |
- |
-void DispatchTableConstructor::VisitAction(ActionNode* that) { |
- RegExpNode* target = that->on_success(); |
- target->Accept(this); |
-} |
- |
- |
-RegExpEngine::CompilationResult RegExpEngine::Compile( |
- Isolate* isolate, Zone* zone, RegExpCompileData* data, bool ignore_case, |
- bool is_global, bool is_multiline, bool is_sticky, Handle<String> pattern, |
- Handle<String> sample_subject, bool is_one_byte) { |
- if ((data->capture_count + 1) * 2 - 1 > RegExpMacroAssembler::kMaxRegister) { |
- return IrregexpRegExpTooBig(isolate); |
- } |
- RegExpCompiler compiler(isolate, zone, data->capture_count, ignore_case, |
- is_one_byte); |
- |
- if (compiler.optimize()) compiler.set_optimize(!TooMuchRegExpCode(pattern)); |
- |
- // Sample some characters from the middle of the string. |
- static const int kSampleSize = 128; |
- |
- sample_subject = String::Flatten(sample_subject); |
- int chars_sampled = 0; |
- int half_way = (sample_subject->length() - kSampleSize) / 2; |
- for (int i = Max(0, half_way); |
- i < sample_subject->length() && chars_sampled < kSampleSize; |
- i++, chars_sampled++) { |
- compiler.frequency_collator()->CountCharacter(sample_subject->Get(i)); |
- } |
- |
- // Wrap the body of the regexp in capture #0. |
- RegExpNode* captured_body = RegExpCapture::ToNode(data->tree, |
- 0, |
- &compiler, |
- compiler.accept()); |
- RegExpNode* node = captured_body; |
- bool is_end_anchored = data->tree->IsAnchoredAtEnd(); |
- bool is_start_anchored = data->tree->IsAnchoredAtStart(); |
- int max_length = data->tree->max_match(); |
- if (!is_start_anchored && !is_sticky) { |
- // Add a .*? at the beginning, outside the body capture, unless |
- // this expression is anchored at the beginning or sticky. |
- RegExpNode* loop_node = |
- RegExpQuantifier::ToNode(0, |
- RegExpTree::kInfinity, |
- false, |
- new(zone) RegExpCharacterClass('*'), |
- &compiler, |
- captured_body, |
- data->contains_anchor); |
- |
- if (data->contains_anchor) { |
- // Unroll loop once, to take care of the case that might start |
- // at the start of input. |
- ChoiceNode* first_step_node = new(zone) ChoiceNode(2, zone); |
- first_step_node->AddAlternative(GuardedAlternative(captured_body)); |
- first_step_node->AddAlternative(GuardedAlternative( |
- new(zone) TextNode(new(zone) RegExpCharacterClass('*'), loop_node))); |
- node = first_step_node; |
- } else { |
- node = loop_node; |
- } |
- } |
- if (is_one_byte) { |
- node = node->FilterOneByte(RegExpCompiler::kMaxRecursion, ignore_case); |
- // Do it again to propagate the new nodes to places where they were not |
- // put because they had not been calculated yet. |
- if (node != NULL) { |
- node = node->FilterOneByte(RegExpCompiler::kMaxRecursion, ignore_case); |
- } |
- } |
- |
- if (node == NULL) node = new(zone) EndNode(EndNode::BACKTRACK, zone); |
- data->node = node; |
- Analysis analysis(isolate, ignore_case, is_one_byte); |
- analysis.EnsureAnalyzed(node); |
- if (analysis.has_failed()) { |
- const char* error_message = analysis.error_message(); |
- return CompilationResult(isolate, error_message); |
- } |
- |
- // Create the correct assembler for the architecture. |
-#ifndef V8_INTERPRETED_REGEXP |
- // Native regexp implementation. |
- |
- NativeRegExpMacroAssembler::Mode mode = |
- is_one_byte ? NativeRegExpMacroAssembler::LATIN1 |
- : NativeRegExpMacroAssembler::UC16; |
- |
-#if V8_TARGET_ARCH_IA32 |
- RegExpMacroAssemblerIA32 macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_X64 |
- RegExpMacroAssemblerX64 macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_ARM |
- RegExpMacroAssemblerARM macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_ARM64 |
- RegExpMacroAssemblerARM64 macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_PPC |
- RegExpMacroAssemblerPPC macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_MIPS |
- RegExpMacroAssemblerMIPS macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_MIPS64 |
- RegExpMacroAssemblerMIPS macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#elif V8_TARGET_ARCH_X87 |
- RegExpMacroAssemblerX87 macro_assembler(isolate, zone, mode, |
- (data->capture_count + 1) * 2); |
-#else |
-#error "Unsupported architecture" |
-#endif |
- |
-#else // V8_INTERPRETED_REGEXP |
- // Interpreted regexp implementation. |
- EmbeddedVector<byte, 1024> codes; |
- RegExpMacroAssemblerIrregexp macro_assembler(isolate, codes, zone); |
-#endif // V8_INTERPRETED_REGEXP |
- |
- macro_assembler.set_slow_safe(TooMuchRegExpCode(pattern)); |
- |
- // Inserted here, instead of in Assembler, because it depends on information |
- // in the AST that isn't replicated in the Node structure. |
- static const int kMaxBacksearchLimit = 1024; |
- if (is_end_anchored && |
- !is_start_anchored && |
- max_length < kMaxBacksearchLimit) { |
- macro_assembler.SetCurrentPositionFromEnd(max_length); |
- } |
- |
- if (is_global) { |
- macro_assembler.set_global_mode( |
- (data->tree->min_match() > 0) |
- ? RegExpMacroAssembler::GLOBAL_NO_ZERO_LENGTH_CHECK |
- : RegExpMacroAssembler::GLOBAL); |
- } |
- |
- return compiler.Assemble(¯o_assembler, |
- node, |
- data->capture_count, |
- pattern); |
-} |
- |
- |
-bool RegExpEngine::TooMuchRegExpCode(Handle<String> pattern) { |
- Heap* heap = pattern->GetHeap(); |
- bool too_much = pattern->length() > RegExpImpl::kRegExpTooLargeToOptimize; |
- if (heap->total_regexp_code_generated() > RegExpImpl::kRegExpCompiledLimit && |
- heap->isolate()->memory_allocator()->SizeExecutable() > |
- RegExpImpl::kRegExpExecutableMemoryLimit) { |
- too_much = true; |
- } |
- return too_much; |
-} |
-} // namespace internal |
-} // namespace v8 |