// 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/codegen/compiler.h"
#include <algorithm>
#include <memory>
#include "src/api/api-inl.h"
#include "src/asmjs/asm-js.h"
#include "src/ast/prettyprinter.h"
#include "src/ast/scopes.h"
#include "src/base/logging.h"
#include "src/base/optional.h"
#include "src/codegen/assembler-inl.h"
#include "src/codegen/compilation-cache.h"
#include "src/codegen/optimized-compilation-info.h"
#include "src/codegen/pending-optimization-table.h"
#include "src/codegen/unoptimized-compilation-info.h"
#include "src/common/assert-scope.h"
#include "src/common/globals.h"
#include "src/common/message-template.h"
#include "src/compiler-dispatcher/compiler-dispatcher.h"
#include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
#include "src/compiler/pipeline.h"
#include "src/debug/debug.h"
#include "src/debug/liveedit.h"
#include "src/diagnostics/code-tracer.h"
#include "src/execution/frames-inl.h"
#include "src/execution/isolate-inl.h"
#include "src/execution/isolate.h"
#include "src/execution/off-thread-isolate.h"
#include "src/execution/runtime-profiler.h"
#include "src/execution/vm-state-inl.h"
#include "src/handles/maybe-handles.h"
#include "src/heap/heap-inl.h"
#include "src/heap/off-thread-factory-inl.h"
#include "src/init/bootstrapper.h"
#include "src/interpreter/interpreter.h"
#include "src/logging/log-inl.h"
#include "src/objects/feedback-cell-inl.h"
#include "src/objects/map.h"
#include "src/objects/object-list-macros.h"
#include "src/objects/shared-function-info.h"
#include "src/objects/string.h"
#include "src/parsing/parse-info.h"
#include "src/parsing/parser.h"
#include "src/parsing/parsing.h"
#include "src/parsing/pending-compilation-error-handler.h"
#include "src/parsing/scanner-character-streams.h"
#include "src/snapshot/code-serializer.h"
#include "src/utils/ostreams.h"
#include "src/zone/zone-list-inl.h" // crbug.com/v8/8816
namespace v8 {
namespace internal {
// A wrapper around a OptimizedCompilationInfo that detaches the Handles from
// the underlying DeferredHandleScope and stores them in info_ on
// destruction.
class CompilationHandleScope final {
public:
explicit CompilationHandleScope(Isolate* isolate,
OptimizedCompilationInfo* info)
: deferred_(isolate), info_(info) {}
~CompilationHandleScope() { info_->set_deferred_handles(deferred_.Detach()); }
private:
DeferredHandleScope deferred_;
OptimizedCompilationInfo* info_;
};
// Helper that times a scoped region and records the elapsed time.
struct ScopedTimer {
explicit ScopedTimer(base::TimeDelta* location) : location_(location) {
DCHECK_NOT_NULL(location_);
timer_.Start();
}
~ScopedTimer() { *location_ += timer_.Elapsed(); }
base::ElapsedTimer timer_;
base::TimeDelta* location_;
};
namespace {
void LogFunctionCompilation(CodeEventListener::LogEventsAndTags tag,
Handle<SharedFunctionInfo> shared,
Handle<Script> script,
Handle<AbstractCode> abstract_code, bool optimizing,
double time_taken_ms, Isolate* isolate) {
DCHECK(!abstract_code.is_null());
DCHECK(!abstract_code.is_identical_to(BUILTIN_CODE(isolate, CompileLazy)));
// Log the code generation. If source information is available include
// script name and line number. Check explicitly whether logging is
// enabled as finding the line number is not free.
if (!isolate->logger()->is_listening_to_code_events() &&
!isolate->is_profiling() && !FLAG_log_function_events &&
!isolate->code_event_dispatcher()->IsListeningToCodeEvents()) {
return;
}
int line_num = Script::GetLineNumber(script, shared->StartPosition()) + 1;
int column_num = Script::GetColumnNumber(script, shared->StartPosition()) + 1;
Handle<String> script_name(script->name().IsString()
? String::cast(script->name())
: ReadOnlyRoots(isolate).empty_string(),
isolate);
CodeEventListener::LogEventsAndTags log_tag =
Logger::ToNativeByScript(tag, *script);
PROFILE(isolate, CodeCreateEvent(log_tag, abstract_code, shared, script_name,
line_num, column_num));
if (!FLAG_log_function_events) return;
DisallowHeapAllocation no_gc;
std::string name = optimizing ? "optimize" : "compile";
switch (tag) {
case CodeEventListener::EVAL_TAG:
name += "-eval";
break;
case CodeEventListener::SCRIPT_TAG:
break;
case CodeEventListener::LAZY_COMPILE_TAG:
name += "-lazy";
break;
case CodeEventListener::FUNCTION_TAG:
break;
default:
UNREACHABLE();
}
LOG(isolate, FunctionEvent(name.c_str(), script->id(), time_taken_ms,
shared->StartPosition(), shared->EndPosition(),
shared->DebugName()));
}
ScriptOriginOptions OriginOptionsForEval(Object script) {
if (!script.IsScript()) return ScriptOriginOptions();
const auto outer_origin_options = Script::cast(script).origin_options();
return ScriptOriginOptions(outer_origin_options.IsSharedCrossOrigin(),
outer_origin_options.IsOpaque());
}
} // namespace
// ----------------------------------------------------------------------------
// Implementation of UnoptimizedCompilationJob
CompilationJob::Status UnoptimizedCompilationJob::ExecuteJob() {
DisallowHeapAccess no_heap_access;
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToExecute);
ScopedTimer t(&time_taken_to_execute_);
return UpdateState(ExecuteJobImpl(), State::kReadyToFinalize);
}
CompilationJob::Status UnoptimizedCompilationJob::FinalizeJob(
Handle<SharedFunctionInfo> shared_info, Isolate* isolate) {
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
DisallowCodeDependencyChange no_dependency_change;
DisallowJavascriptExecution no_js(isolate);
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToFinalize);
ScopedTimer t(&time_taken_to_finalize_);
return UpdateState(FinalizeJobImpl(shared_info, isolate), State::kSucceeded);
}
CompilationJob::Status UnoptimizedCompilationJob::FinalizeJob(
Handle<SharedFunctionInfo> shared_info, OffThreadIsolate* isolate) {
DisallowHeapAccess no_heap_access;
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToFinalize);
ScopedTimer t(&time_taken_to_finalize_);
return UpdateState(FinalizeJobImpl(shared_info, isolate), State::kSucceeded);
}
namespace {
void RecordUnoptimizedCompilationStats(Isolate* isolate,
Handle<SharedFunctionInfo> shared_info) {
int code_size;
if (shared_info->HasBytecodeArray()) {
code_size = shared_info->GetBytecodeArray().SizeIncludingMetadata();
} else {
code_size = shared_info->asm_wasm_data().Size();
}
Counters* counters = isolate->counters();
// TODO(4280): Rename counters from "baseline" to "unoptimized" eventually.
counters->total_baseline_code_size()->Increment(code_size);
counters->total_baseline_compile_count()->Increment(1);
// TODO(5203): Add timers for each phase of compilation.
// Also add total time (there's now already timer_ on the base class).
}
void RecordUnoptimizedFunctionCompilation(
Isolate* isolate, CodeEventListener::LogEventsAndTags tag,
Handle<SharedFunctionInfo> shared, base::TimeDelta time_taken_to_execute,
base::TimeDelta time_taken_to_finalize) {
Handle<AbstractCode> abstract_code;
if (shared->HasBytecodeArray()) {
abstract_code =
handle(AbstractCode::cast(shared->GetBytecodeArray()), isolate);
} else {
DCHECK(shared->HasAsmWasmData());
abstract_code =
Handle<AbstractCode>::cast(BUILTIN_CODE(isolate, InstantiateAsmJs));
}
double time_taken_ms = time_taken_to_execute.InMillisecondsF() +
time_taken_to_finalize.InMillisecondsF();
Handle<Script> script(Script::cast(shared->script()), isolate);
LogFunctionCompilation(tag, shared, script, abstract_code, false,
time_taken_ms, isolate);
}
} // namespace
// ----------------------------------------------------------------------------
// Implementation of OptimizedCompilationJob
CompilationJob::Status OptimizedCompilationJob::PrepareJob(Isolate* isolate) {
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
DisallowJavascriptExecution no_js(isolate);
if (FLAG_trace_opt && compilation_info()->IsOptimizing()) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
OFStream os(scope.file());
os << "[compiling method " << Brief(*compilation_info()->closure())
<< " using " << compiler_name_;
if (compilation_info()->is_osr()) os << " OSR";
os << "]" << std::endl;
}
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToPrepare);
ScopedTimer t(&time_taken_to_prepare_);
return UpdateState(PrepareJobImpl(isolate), State::kReadyToExecute);
}
CompilationJob::Status OptimizedCompilationJob::ExecuteJob(
RuntimeCallStats* stats) {
DisallowHeapAccess no_heap_access;
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToExecute);
ScopedTimer t(&time_taken_to_execute_);
return UpdateState(ExecuteJobImpl(stats), State::kReadyToFinalize);
}
CompilationJob::Status OptimizedCompilationJob::FinalizeJob(Isolate* isolate) {
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
DisallowJavascriptExecution no_js(isolate);
// Delegate to the underlying implementation.
DCHECK_EQ(state(), State::kReadyToFinalize);
ScopedTimer t(&time_taken_to_finalize_);
return UpdateState(FinalizeJobImpl(isolate), State::kSucceeded);
}
CompilationJob::Status OptimizedCompilationJob::RetryOptimization(
BailoutReason reason) {
DCHECK(compilation_info_->IsOptimizing());
compilation_info_->RetryOptimization(reason);
return UpdateState(FAILED, State::kFailed);
}
CompilationJob::Status OptimizedCompilationJob::AbortOptimization(
BailoutReason reason) {
DCHECK(compilation_info_->IsOptimizing());
compilation_info_->AbortOptimization(reason);
return UpdateState(FAILED, State::kFailed);
}
void OptimizedCompilationJob::RecordCompilationStats(CompilationMode mode,
Isolate* isolate) const {
DCHECK(compilation_info()->IsOptimizing());
Handle<JSFunction> function = compilation_info()->closure();
double ms_creategraph = time_taken_to_prepare_.InMillisecondsF();
double ms_optimize = time_taken_to_execute_.InMillisecondsF();
double ms_codegen = time_taken_to_finalize_.InMillisecondsF();
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[optimizing ");
function->ShortPrint(scope.file());
PrintF(scope.file(), " - took %0.3f, %0.3f, %0.3f ms]\n", ms_creategraph,
ms_optimize, ms_codegen);
}
if (FLAG_trace_opt_stats) {
static double compilation_time = 0.0;
static int compiled_functions = 0;
static int code_size = 0;
compilation_time += (ms_creategraph + ms_optimize + ms_codegen);
compiled_functions++;
code_size += function->shared().SourceSize();
PrintF("Compiled: %d functions with %d byte source size in %fms.\n",
compiled_functions, code_size, compilation_time);
}
// Don't record samples from machines without high-resolution timers,
// as that can cause serious reporting issues. See the thread at
// http://g/chrome-metrics-team/NwwJEyL8odU/discussion for more details.
if (base::TimeTicks::IsHighResolution()) {
Counters* const counters = isolate->counters();
if (compilation_info()->is_osr()) {
counters->turbofan_osr_prepare()->AddSample(
static_cast<int>(time_taken_to_prepare_.InMicroseconds()));
counters->turbofan_osr_execute()->AddSample(
static_cast<int>(time_taken_to_execute_.InMicroseconds()));
counters->turbofan_osr_finalize()->AddSample(
static_cast<int>(time_taken_to_finalize_.InMicroseconds()));
counters->turbofan_osr_total_time()->AddSample(
static_cast<int>(ElapsedTime().InMicroseconds()));
} else {
counters->turbofan_optimize_prepare()->AddSample(
static_cast<int>(time_taken_to_prepare_.InMicroseconds()));
counters->turbofan_optimize_execute()->AddSample(
static_cast<int>(time_taken_to_execute_.InMicroseconds()));
counters->turbofan_optimize_finalize()->AddSample(
static_cast<int>(time_taken_to_finalize_.InMicroseconds()));
counters->turbofan_optimize_total_time()->AddSample(
static_cast<int>(ElapsedTime().InMicroseconds()));
// Compute foreground / background time.
base::TimeDelta time_background;
base::TimeDelta time_foreground =
time_taken_to_prepare_ + time_taken_to_finalize_;
switch (mode) {
case OptimizedCompilationJob::kConcurrent:
time_background += time_taken_to_execute_;
counters->turbofan_optimize_concurrent_total_time()->AddSample(
static_cast<int>(ElapsedTime().InMicroseconds()));
break;
case OptimizedCompilationJob::kSynchronous:
counters->turbofan_optimize_non_concurrent_total_time()->AddSample(
static_cast<int>(ElapsedTime().InMicroseconds()));
time_foreground += time_taken_to_execute_;
break;
}
counters->turbofan_optimize_total_background()->AddSample(
static_cast<int>(time_background.InMicroseconds()));
counters->turbofan_optimize_total_foreground()->AddSample(
static_cast<int>(time_foreground.InMicroseconds()));
}
counters->turbofan_ticks()->AddSample(static_cast<int>(
compilation_info()->tick_counter().CurrentTicks() / 1000));
}
}
void OptimizedCompilationJob::RecordFunctionCompilation(
CodeEventListener::LogEventsAndTags tag, Isolate* isolate) const {
Handle<AbstractCode> abstract_code =
Handle<AbstractCode>::cast(compilation_info()->code());
double time_taken_ms = time_taken_to_prepare_.InMillisecondsF() +
time_taken_to_execute_.InMillisecondsF() +
time_taken_to_finalize_.InMillisecondsF();
Handle<Script> script(
Script::cast(compilation_info()->shared_info()->script()), isolate);
LogFunctionCompilation(tag, compilation_info()->shared_info(), script,
abstract_code, true, time_taken_ms, isolate);
}
// ----------------------------------------------------------------------------
// Local helper methods that make up the compilation pipeline.
namespace {
bool UseAsmWasm(FunctionLiteral* literal, bool asm_wasm_broken) {
// Check whether asm.js validation is enabled.
if (!FLAG_validate_asm) return false;
// Modules that have validated successfully, but were subsequently broken by
// invalid module instantiation attempts are off limit forever.
if (asm_wasm_broken) return false;
// In stress mode we want to run the validator on everything.
if (FLAG_stress_validate_asm) return true;
// In general, we respect the "use asm" directive.
return literal->scope()->IsAsmModule();
}
void InstallInterpreterTrampolineCopy(Isolate* isolate,
Handle<SharedFunctionInfo> shared_info) {
DCHECK(FLAG_interpreted_frames_native_stack);
if (!shared_info->function_data().IsBytecodeArray()) {
DCHECK(!shared_info->HasBytecodeArray());
return;
}
Handle<BytecodeArray> bytecode_array(shared_info->GetBytecodeArray(),
isolate);
Handle<Code> code = isolate->factory()->CopyCode(Handle<Code>::cast(
isolate->factory()->interpreter_entry_trampoline_for_profiling()));
Handle<InterpreterData> interpreter_data =
Handle<InterpreterData>::cast(isolate->factory()->NewStruct(
INTERPRETER_DATA_TYPE, AllocationType::kOld));
interpreter_data->set_bytecode_array(*bytecode_array);
interpreter_data->set_interpreter_trampoline(*code);
shared_info->set_interpreter_data(*interpreter_data);
Handle<Script> script(Script::cast(shared_info->script()), isolate);
Handle<AbstractCode> abstract_code = Handle<AbstractCode>::cast(code);
int line_num =
Script::GetLineNumber(script, shared_info->StartPosition()) + 1;
int column_num =
Script::GetColumnNumber(script, shared_info->StartPosition()) + 1;
Handle<String> script_name =
handle(script->name().IsString() ? String::cast(script->name())
: ReadOnlyRoots(isolate).empty_string(),
isolate);
CodeEventListener::LogEventsAndTags log_tag = Logger::ToNativeByScript(
CodeEventListener::INTERPRETED_FUNCTION_TAG, *script);
PROFILE(isolate, CodeCreateEvent(log_tag, abstract_code, shared_info,
script_name, line_num, column_num));
}
void InstallCoverageInfo(Isolate* isolate, Handle<SharedFunctionInfo> shared,
Handle<CoverageInfo> coverage_info) {
DCHECK(isolate->is_block_code_coverage());
isolate->debug()->InstallCoverageInfo(shared, coverage_info);
}
void InstallCoverageInfo(OffThreadIsolate* isolate,
Handle<SharedFunctionInfo> shared,
Handle<CoverageInfo> coverage_info) {
// We should only have coverage info when finalizing on the main thread.
UNREACHABLE();
}
template <typename LocalIsolate>
void InstallUnoptimizedCode(UnoptimizedCompilationInfo* compilation_info,
Handle<SharedFunctionInfo> shared_info,
LocalIsolate* isolate) {
DCHECK_EQ(shared_info->language_mode(),
compilation_info->literal()->language_mode());
// Update the shared function info with the scope info.
Handle<ScopeInfo> scope_info = compilation_info->scope()->scope_info();
shared_info->set_scope_info(*scope_info);
if (compilation_info->has_bytecode_array()) {
DCHECK(!shared_info->HasBytecodeArray()); // Only compiled once.
DCHECK(!compilation_info->has_asm_wasm_data());
DCHECK(!shared_info->HasFeedbackMetadata());
// If the function failed asm-wasm compilation, mark asm_wasm as broken
// to ensure we don't try to compile as asm-wasm.
if (compilation_info->literal()->scope()->IsAsmModule()) {
shared_info->set_is_asm_wasm_broken(true);
}
shared_info->set_bytecode_array(*compilation_info->bytecode_array());
Handle<FeedbackMetadata> feedback_metadata = FeedbackMetadata::New(
isolate, compilation_info->feedback_vector_spec());
shared_info->set_feedback_metadata(*feedback_metadata);
} else {
DCHECK(compilation_info->has_asm_wasm_data());
// We should only have asm/wasm data when finalizing on the main thread.
DCHECK((std::is_same<LocalIsolate, Isolate>::value));
shared_info->set_asm_wasm_data(*compilation_info->asm_wasm_data());
shared_info->set_feedback_metadata(
ReadOnlyRoots(isolate).empty_feedback_metadata());
}
if (compilation_info->has_coverage_info() &&
!shared_info->HasCoverageInfo()) {
InstallCoverageInfo(isolate, shared_info,
compilation_info->coverage_info());
}
}
void LogUnoptimizedCompilation(Isolate* isolate,
Handle<SharedFunctionInfo> shared_info,
UnoptimizedCompileFlags flags,
base::TimeDelta time_taken_to_execute,
base::TimeDelta time_taken_to_finalize) {
CodeEventListener::LogEventsAndTags log_tag;
if (flags.is_toplevel()) {
log_tag = flags.is_eval() ? CodeEventListener::EVAL_TAG
: CodeEventListener::SCRIPT_TAG;
} else {
log_tag = flags.is_lazy_compile() ? CodeEventListener::LAZY_COMPILE_TAG
: CodeEventListener::FUNCTION_TAG;
}
RecordUnoptimizedFunctionCompilation(isolate, log_tag, shared_info,
time_taken_to_execute,
time_taken_to_finalize);
RecordUnoptimizedCompilationStats(isolate, shared_info);
}
template <typename LocalIsolate>
void EnsureSharedFunctionInfosArrayOnScript(Handle<Script> script,
ParseInfo* parse_info,
LocalIsolate* isolate) {
DCHECK(parse_info->flags().is_toplevel());
if (script->shared_function_infos().length() > 0) {
DCHECK_EQ(script->shared_function_infos().length(),
parse_info->max_function_literal_id() + 1);
return;
}
Handle<WeakFixedArray> infos(isolate->factory()->NewWeakFixedArray(
parse_info->max_function_literal_id() + 1, AllocationType::kOld));
script->set_shared_function_infos(*infos);
}
void SetSharedFunctionFlagsFromLiteral(FunctionLiteral* literal,
SharedFunctionInfo shared_info) {
shared_info.set_has_duplicate_parameters(literal->has_duplicate_parameters());
shared_info.set_is_oneshot_iife(literal->is_oneshot_iife());
shared_info.UpdateAndFinalizeExpectedNofPropertiesFromEstimate(literal);
if (literal->dont_optimize_reason() != BailoutReason::kNoReason) {
shared_info.DisableOptimization(literal->dont_optimize_reason());
}
shared_info.set_class_scope_has_private_brand(
literal->class_scope_has_private_brand());
shared_info.set_is_safe_to_skip_arguments_adaptor(
literal->SafeToSkipArgumentsAdaptor());
shared_info.set_has_static_private_methods_or_accessors(
literal->has_static_private_methods_or_accessors());
}
template <typename LocalIsolate>
CompilationJob::Status FinalizeSingleUnoptimizedCompilationJob(
UnoptimizedCompilationJob* job, Handle<SharedFunctionInfo> shared_info,
LocalIsolate* isolate,
FinalizeUnoptimizedCompilationDataList*
finalize_unoptimized_compilation_data_list) {
UnoptimizedCompilationInfo* compilation_info = job->compilation_info();
SetSharedFunctionFlagsFromLiteral(compilation_info->literal(), *shared_info);
CompilationJob::Status status = job->FinalizeJob(shared_info, isolate);
if (status == CompilationJob::SUCCEEDED) {
InstallUnoptimizedCode(compilation_info, shared_info, isolate);
finalize_unoptimized_compilation_data_list->emplace_back(
isolate, shared_info, job->time_taken_to_execute(),
job->time_taken_to_finalize());
}
return status;
}
std::unique_ptr<UnoptimizedCompilationJob>
ExecuteSingleUnoptimizedCompilationJob(
ParseInfo* parse_info, FunctionLiteral* literal,
AccountingAllocator* allocator,
std::vector<FunctionLiteral*>* eager_inner_literals) {
if (UseAsmWasm(literal, parse_info->flags().is_asm_wasm_broken())) {
std::unique_ptr<UnoptimizedCompilationJob> asm_job(
AsmJs::NewCompilationJob(parse_info, literal, allocator));
if (asm_job->ExecuteJob() == CompilationJob::SUCCEEDED) {
return asm_job;
}
// asm.js validation failed, fall through to standard unoptimized compile.
// Note: we rely on the fact that AsmJs jobs have done all validation in the
// PrepareJob and ExecuteJob phases and can't fail in FinalizeJob with
// with a validation error or another error that could be solve by falling
// through to standard unoptimized compile.
}
std::unique_ptr<UnoptimizedCompilationJob> job(
interpreter::Interpreter::NewCompilationJob(
parse_info, literal, allocator, eager_inner_literals));
if (job->ExecuteJob() != CompilationJob::SUCCEEDED) {
// Compilation failed, return null.
return std::unique_ptr<UnoptimizedCompilationJob>();
}
return job;
}
std::unique_ptr<UnoptimizedCompilationJob>
RecursivelyExecuteUnoptimizedCompilationJobs(
ParseInfo* parse_info, FunctionLiteral* literal,
AccountingAllocator* allocator,
UnoptimizedCompilationJobList* inner_function_jobs) {
std::vector<FunctionLiteral*> eager_inner_literals;
std::unique_ptr<UnoptimizedCompilationJob> job =
ExecuteSingleUnoptimizedCompilationJob(parse_info, literal, allocator,
&eager_inner_literals);
if (!job) return std::unique_ptr<UnoptimizedCompilationJob>();
// Recursively compile eager inner literals.
for (FunctionLiteral* inner_literal : eager_inner_literals) {
std::unique_ptr<UnoptimizedCompilationJob> inner_job(
RecursivelyExecuteUnoptimizedCompilationJobs(
parse_info, inner_literal, allocator, inner_function_jobs));
// Compilation failed, return null.
if (!inner_job) return std::unique_ptr<UnoptimizedCompilationJob>();
inner_function_jobs->emplace_front(std::move(inner_job));
}
return job;
}
bool IterativelyExecuteAndFinalizeUnoptimizedCompilationJobs(
Isolate* isolate, Handle<SharedFunctionInfo> outer_shared_info,
Handle<Script> script, ParseInfo* parse_info,
AccountingAllocator* allocator, IsCompiledScope* is_compiled_scope,
FinalizeUnoptimizedCompilationDataList*
finalize_unoptimized_compilation_data_list) {
DeclarationScope::AllocateScopeInfos(parse_info, isolate);
std::vector<FunctionLiteral*> functions_to_compile;
functions_to_compile.push_back(parse_info->literal());
while (!functions_to_compile.empty()) {
FunctionLiteral* literal = functions_to_compile.back();
functions_to_compile.pop_back();
Handle<SharedFunctionInfo> shared_info =
Compiler::GetSharedFunctionInfo(literal, script, isolate);
if (shared_info->is_compiled()) continue;
std::unique_ptr<UnoptimizedCompilationJob> job =
ExecuteSingleUnoptimizedCompilationJob(parse_info, literal, allocator,
&functions_to_compile);
if (!job) return false;
if (FinalizeSingleUnoptimizedCompilationJob(
job.get(), shared_info, isolate,
finalize_unoptimized_compilation_data_list) !=
CompilationJob::SUCCEEDED) {
return false;
}
if (shared_info.is_identical_to(outer_shared_info)) {
// Ensure that the top level function is retained.
*is_compiled_scope = shared_info->is_compiled_scope();
DCHECK(is_compiled_scope->is_compiled());
}
}
// Report any warnings generated during compilation.
if (parse_info->pending_error_handler()->has_pending_warnings()) {
parse_info->pending_error_handler()->PrepareWarnings(isolate);
}
return true;
}
template <typename LocalIsolate>
bool FinalizeAllUnoptimizedCompilationJobs(
ParseInfo* parse_info, LocalIsolate* isolate,
Handle<SharedFunctionInfo> shared_info,
UnoptimizedCompilationJob* outer_function_job,
UnoptimizedCompilationJobList* inner_function_jobs,
FinalizeUnoptimizedCompilationDataList*
finalize_unoptimized_compilation_data_list) {
// TODO(leszeks): Re-enable.
// DCHECK(AllowCompilation::IsAllowed(isolate));
// TODO(rmcilroy): Clear native context in debug once AsmJS generates doesn't
// rely on accessing native context during finalization.
// Allocate scope infos for the literal.
DeclarationScope::AllocateScopeInfos(parse_info, isolate);
// Finalize the outer-most function's compilation job.
if (FinalizeSingleUnoptimizedCompilationJob(
outer_function_job, shared_info, isolate,
finalize_unoptimized_compilation_data_list) !=
CompilationJob::SUCCEEDED) {
return false;
}
Handle<Script> script(Script::cast(shared_info->script()), isolate);
parse_info->CheckFlagsForFunctionFromScript(*script);
// Finalize the inner functions' compilation jobs.
for (auto&& inner_job : *inner_function_jobs) {
Handle<SharedFunctionInfo> inner_shared_info =
Compiler::GetSharedFunctionInfo(
inner_job->compilation_info()->literal(), script, isolate);
// The inner function might be compiled already if compiling for debug.
if (inner_shared_info->is_compiled()) continue;
if (FinalizeSingleUnoptimizedCompilationJob(
inner_job.get(), inner_shared_info, isolate,
finalize_unoptimized_compilation_data_list) !=
CompilationJob::SUCCEEDED) {
return false;
}
}
// Report any warnings generated during compilation.
if (parse_info->pending_error_handler()->has_pending_warnings()) {
parse_info->pending_error_handler()->PrepareWarnings(isolate);
}
return true;
}
V8_WARN_UNUSED_RESULT MaybeHandle<Code> GetCodeFromOptimizedCodeCache(
Handle<JSFunction> function, BailoutId osr_offset) {
RuntimeCallTimerScope runtimeTimer(
function->GetIsolate(),
RuntimeCallCounterId::kCompileGetFromOptimizedCodeMap);
Handle<SharedFunctionInfo> shared(function->shared(), function->GetIsolate());
Isolate* isolate = function->GetIsolate();
DisallowHeapAllocation no_gc;
Code code;
if (osr_offset.IsNone() && function->has_feedback_vector()) {
FeedbackVector feedback_vector = function->feedback_vector();
feedback_vector.EvictOptimizedCodeMarkedForDeoptimization(
function->shared(), "GetCodeFromOptimizedCodeCache");
code = feedback_vector.optimized_code();
} else if (!osr_offset.IsNone()) {
code = function->context()
.native_context()
.GetOSROptimizedCodeCache()
.GetOptimizedCode(shared, osr_offset, isolate);
}
if (!code.is_null()) {
// Caching of optimized code enabled and optimized code found.
DCHECK(!code.marked_for_deoptimization());
DCHECK(function->shared().is_compiled());
return Handle<Code>(code, isolate);
}
return MaybeHandle<Code>();
}
void ClearOptimizedCodeCache(OptimizedCompilationInfo* compilation_info) {
Handle<JSFunction> function = compilation_info->closure();
if (compilation_info->osr_offset().IsNone()) {
Handle<FeedbackVector> vector =
handle(function->feedback_vector(), function->GetIsolate());
vector->ClearOptimizationMarker();
}
}
void InsertCodeIntoOptimizedCodeCache(
OptimizedCompilationInfo* compilation_info) {
Handle<Code> code = compilation_info->code();
if (code->kind() != Code::OPTIMIZED_FUNCTION) return; // Nothing to do.
// Function context specialization folds-in the function context,
// so no sharing can occur.
if (compilation_info->is_function_context_specializing()) {
// Native context specialized code is not shared, so make sure the optimized
// code cache is clear.
ClearOptimizedCodeCache(compilation_info);
return;
}
// Cache optimized context-specific code.
Handle<JSFunction> function = compilation_info->closure();
Handle<SharedFunctionInfo> shared(function->shared(), function->GetIsolate());
Handle<NativeContext> native_context(function->context().native_context(),
function->GetIsolate());
if (compilation_info->osr_offset().IsNone()) {
Handle<FeedbackVector> vector =
handle(function->feedback_vector(), function->GetIsolate());
FeedbackVector::SetOptimizedCode(vector, code);
} else {
OSROptimizedCodeCache::AddOptimizedCode(native_context, shared, code,
compilation_info->osr_offset());
}
}
bool GetOptimizedCodeNow(OptimizedCompilationJob* job, Isolate* isolate) {
TimerEventScope<TimerEventRecompileSynchronous> timer(isolate);
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kOptimizeNonConcurrent);
OptimizedCompilationInfo* compilation_info = job->compilation_info();
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.OptimizeNonConcurrent");
if (job->PrepareJob(isolate) != CompilationJob::SUCCEEDED ||
job->ExecuteJob(isolate->counters()->runtime_call_stats()) !=
CompilationJob::SUCCEEDED ||
job->FinalizeJob(isolate) != CompilationJob::SUCCEEDED) {
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[aborted optimizing ");
compilation_info->closure()->ShortPrint(scope.file());
PrintF(scope.file(), " because: %s]\n",
GetBailoutReason(compilation_info->bailout_reason()));
}
return false;
}
// Success!
job->RecordCompilationStats(OptimizedCompilationJob::kSynchronous, isolate);
DCHECK(!isolate->has_pending_exception());
InsertCodeIntoOptimizedCodeCache(compilation_info);
job->RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG, isolate);
return true;
}
bool GetOptimizedCodeLater(OptimizedCompilationJob* job, Isolate* isolate) {
OptimizedCompilationInfo* compilation_info = job->compilation_info();
if (!isolate->optimizing_compile_dispatcher()->IsQueueAvailable()) {
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Compilation queue full, will retry optimizing ");
compilation_info->closure()->ShortPrint();
PrintF(" later.\n");
}
return false;
}
if (isolate->heap()->HighMemoryPressure()) {
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** High memory pressure, will retry optimizing ");
compilation_info->closure()->ShortPrint();
PrintF(" later.\n");
}
return false;
}
TimerEventScope<TimerEventRecompileSynchronous> timer(isolate);
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kOptimizeConcurrentPrepare);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.OptimizeConcurrentPrepare");
if (job->PrepareJob(isolate) != CompilationJob::SUCCEEDED) return false;
isolate->optimizing_compile_dispatcher()->QueueForOptimization(job);
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Queued ");
compilation_info->closure()->ShortPrint();
PrintF(" for concurrent optimization.\n");
}
return true;
}
MaybeHandle<Code> GetOptimizedCode(Handle<JSFunction> function,
ConcurrencyMode mode,
BailoutId osr_offset = BailoutId::None(),
JavaScriptFrame* osr_frame = nullptr) {
Isolate* isolate = function->GetIsolate();
Handle<SharedFunctionInfo> shared(function->shared(), isolate);
// Make sure we clear the optimization marker on the function so that we
// don't try to re-optimize.
if (function->HasOptimizationMarker()) {
function->ClearOptimizationMarker();
}
if (shared->optimization_disabled() &&
shared->disable_optimization_reason() == BailoutReason::kNeverOptimize) {
return MaybeHandle<Code>();
}
if (isolate->debug()->needs_check_on_function_call()) {
// Do not optimize when debugger needs to hook into every call.
return MaybeHandle<Code>();
}
// If code was pending optimization for testing, delete remove the entry
// from the table that was preventing the bytecode from being flushed
if (V8_UNLIKELY(FLAG_testing_d8_test_runner)) {
PendingOptimizationTable::FunctionWasOptimized(isolate, function);
}
Handle<Code> cached_code;
if (GetCodeFromOptimizedCodeCache(function, osr_offset)
.ToHandle(&cached_code)) {
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[found optimized code for ");
function->ShortPrint(scope.file());
if (!osr_offset.IsNone()) {
PrintF(scope.file(), " at OSR AST id %d", osr_offset.ToInt());
}
PrintF(scope.file(), "]\n");
}
return cached_code;
}
// Reset profiler ticks, function is no longer considered hot.
DCHECK(shared->is_compiled());
function->feedback_vector().set_profiler_ticks(0);
VMState<COMPILER> state(isolate);
TimerEventScope<TimerEventOptimizeCode> optimize_code_timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate,
RuntimeCallCounterId::kOptimizeCode);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.OptimizeCode");
DCHECK(!isolate->has_pending_exception());
PostponeInterruptsScope postpone(isolate);
bool has_script = shared->script().IsScript();
// BUG(5946): This DCHECK is necessary to make certain that we won't
// tolerate the lack of a script without bytecode.
DCHECK_IMPLIES(!has_script, shared->HasBytecodeArray());
std::unique_ptr<OptimizedCompilationJob> job(
compiler::Pipeline::NewCompilationJob(isolate, function, has_script,
osr_offset, osr_frame));
OptimizedCompilationInfo* compilation_info = job->compilation_info();
// Do not use TurboFan if we need to be able to set break points.
if (compilation_info->shared_info()->HasBreakInfo()) {
compilation_info->AbortOptimization(BailoutReason::kFunctionBeingDebugged);
return MaybeHandle<Code>();
}
// Do not use TurboFan if optimization is disabled or function doesn't pass
// turbo_filter.
if (!FLAG_opt || !shared->PassesFilter(FLAG_turbo_filter)) {
compilation_info->AbortOptimization(BailoutReason::kOptimizationDisabled);
return MaybeHandle<Code>();
}
// In case of concurrent recompilation, all handles below this point will be
// allocated in a deferred handle scope that is detached and handed off to
// the background thread when we return.
base::Optional<CompilationHandleScope> compilation;
if (mode == ConcurrencyMode::kConcurrent) {
compilation.emplace(isolate, compilation_info);
}
// All handles below will be canonicalized.
CanonicalHandleScope canonical(isolate);
// Reopen handles in the new CompilationHandleScope.
compilation_info->ReopenHandlesInNewHandleScope(isolate);
if (mode == ConcurrencyMode::kConcurrent) {
if (GetOptimizedCodeLater(job.get(), isolate)) {
job.release(); // The background recompile job owns this now.
// Set the optimization marker and return a code object which checks it.
function->SetOptimizationMarker(OptimizationMarker::kInOptimizationQueue);
DCHECK(function->IsInterpreted() ||
(!function->is_compiled() && function->shared().IsInterpreted()));
DCHECK(function->shared().HasBytecodeArray());
return BUILTIN_CODE(isolate, InterpreterEntryTrampoline);
}
} else {
if (GetOptimizedCodeNow(job.get(), isolate))
return compilation_info->code();
}
if (isolate->has_pending_exception()) isolate->clear_pending_exception();
return MaybeHandle<Code>();
}
bool FailAndClearPendingException(Isolate* isolate) {
isolate->clear_pending_exception();
return false;
}
template <typename LocalIsolate>
bool PreparePendingException(LocalIsolate* isolate, ParseInfo* parse_info) {
if (parse_info->pending_error_handler()->has_pending_error()) {
parse_info->pending_error_handler()->PrepareErrors(
isolate, parse_info->ast_value_factory());
}
return false;
}
bool FailWithPreparedPendingException(
Isolate* isolate, Handle<Script> script,
const PendingCompilationErrorHandler* pending_error_handler) {
if (!isolate->has_pending_exception()) {
if (pending_error_handler->has_pending_error()) {
pending_error_handler->ReportErrors(isolate, script);
} else {
isolate->StackOverflow();
}
}
return false;
}
bool FailWithPendingException(Isolate* isolate, Handle<Script> script,
ParseInfo* parse_info,
Compiler::ClearExceptionFlag flag) {
if (flag == Compiler::CLEAR_EXCEPTION) {
return FailAndClearPendingException(isolate);
}
PreparePendingException(isolate, parse_info);
return FailWithPreparedPendingException(isolate, script,
parse_info->pending_error_handler());
}
void FinalizeUnoptimizedCompilation(
Isolate* isolate, Handle<Script> script,
const UnoptimizedCompileFlags& flags,
const UnoptimizedCompileState* compile_state,
const FinalizeUnoptimizedCompilationDataList&
finalize_unoptimized_compilation_data_list) {
if (compile_state->pending_error_handler()->has_pending_warnings()) {
compile_state->pending_error_handler()->ReportWarnings(isolate, script);
}
bool need_source_positions = FLAG_stress_lazy_source_positions ||
(!flags.collect_source_positions() &&
isolate->NeedsSourcePositionsForProfiling());
for (const auto& finalize_data : finalize_unoptimized_compilation_data_list) {
Handle<SharedFunctionInfo> shared_info = finalize_data.function_handle();
// It's unlikely, but possible, that the bytecode was flushed between being
// allocated and now, so guard against that case, and against it being
// flushed in the middle of this loop.
IsCompiledScope is_compiled_scope(*shared_info, isolate);
if (!is_compiled_scope.is_compiled()) continue;
if (need_source_positions) {
SharedFunctionInfo::EnsureSourcePositionsAvailable(isolate, shared_info);
}
if (FLAG_interpreted_frames_native_stack) {
InstallInterpreterTrampolineCopy(isolate, shared_info);
}
LogUnoptimizedCompilation(isolate, shared_info, flags,
finalize_data.time_taken_to_execute(),
finalize_data.time_taken_to_finalize());
}
}
void FinalizeUnoptimizedScriptCompilation(
Isolate* isolate, Handle<Script> script,
const UnoptimizedCompileFlags& flags,
const UnoptimizedCompileState* compile_state,
const FinalizeUnoptimizedCompilationDataList&
finalize_unoptimized_compilation_data_list) {
FinalizeUnoptimizedCompilation(isolate, script, flags, compile_state,
finalize_unoptimized_compilation_data_list);
script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
UnoptimizedCompileState::ParallelTasks* parallel_tasks =
compile_state->parallel_tasks();
if (parallel_tasks) {
CompilerDispatcher* dispatcher = parallel_tasks->dispatcher();
for (auto& it : *parallel_tasks) {
FunctionLiteral* literal = it.first;
CompilerDispatcher::JobId job_id = it.second;
MaybeHandle<SharedFunctionInfo> maybe_shared_for_task =
script->FindSharedFunctionInfo(isolate,
literal->function_literal_id());
Handle<SharedFunctionInfo> shared_for_task;
if (maybe_shared_for_task.ToHandle(&shared_for_task)) {
dispatcher->RegisterSharedFunctionInfo(job_id, *shared_for_task);
} else {
dispatcher->AbortJob(job_id);
}
}
}
if (isolate->NeedsSourcePositionsForProfiling()) {
Script::InitLineEnds(isolate, script);
}
}
// Create shared function info for top level and shared function infos array for
// inner functions.
template <typename LocalIsolate>
Handle<SharedFunctionInfo> CreateTopLevelSharedFunctionInfo(
ParseInfo* parse_info, Handle<Script> script, LocalIsolate* isolate) {
EnsureSharedFunctionInfosArrayOnScript(script, parse_info, isolate);
DCHECK_EQ(kNoSourcePosition,
parse_info->literal()->function_token_position());
return isolate->factory()->NewSharedFunctionInfoForLiteral(
parse_info->literal(), script, true);
}
MaybeHandle<SharedFunctionInfo> CompileToplevel(
ParseInfo* parse_info, Handle<Script> script,
MaybeHandle<ScopeInfo> maybe_outer_scope_info, Isolate* isolate,
IsCompiledScope* is_compiled_scope) {
TimerEventScope<TimerEventCompileCode> top_level_timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileCode");
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
PostponeInterruptsScope postpone(isolate);
DCHECK(!isolate->native_context().is_null());
RuntimeCallTimerScope runtimeTimer(
isolate, parse_info->flags().is_eval()
? RuntimeCallCounterId::kCompileEval
: RuntimeCallCounterId::kCompileScript);
VMState<BYTECODE_COMPILER> state(isolate);
if (parse_info->literal() == nullptr &&
!parsing::ParseProgram(parse_info, script, maybe_outer_scope_info,
isolate)) {
return MaybeHandle<SharedFunctionInfo>();
}
// Measure how long it takes to do the compilation; only take the
// rest of the function into account to avoid overlap with the
// parsing statistics.
HistogramTimer* rate = parse_info->flags().is_eval()
? isolate->counters()->compile_eval()
: isolate->counters()->compile();
HistogramTimerScope timer(rate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
parse_info->flags().is_eval() ? "V8.CompileEval" : "V8.Compile");
// Prepare and execute compilation of the outer-most function.
// Create the SharedFunctionInfo and add it to the script's list.
Handle<SharedFunctionInfo> shared_info =
CreateTopLevelSharedFunctionInfo(parse_info, script, isolate);
FinalizeUnoptimizedCompilationDataList
finalize_unoptimized_compilation_data_list;
if (!IterativelyExecuteAndFinalizeUnoptimizedCompilationJobs(
isolate, shared_info, script, parse_info, isolate->allocator(),
is_compiled_scope, &finalize_unoptimized_compilation_data_list)) {
FailWithPendingException(isolate, script, parse_info,
Compiler::ClearExceptionFlag::KEEP_EXCEPTION);
return MaybeHandle<SharedFunctionInfo>();
}
// Character stream shouldn't be used again.
parse_info->ResetCharacterStream();
FinalizeUnoptimizedScriptCompilation(
isolate, script, parse_info->flags(), parse_info->state(),
finalize_unoptimized_compilation_data_list);
return shared_info;
}
std::unique_ptr<UnoptimizedCompilationJob> CompileOnBackgroundThread(
ParseInfo* parse_info, AccountingAllocator* allocator,
UnoptimizedCompilationJobList* inner_function_jobs) {
DisallowHeapAccess no_heap_access;
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CompileCodeBackground");
RuntimeCallTimerScope runtimeTimer(
parse_info->runtime_call_stats(),
parse_info->flags().is_toplevel()
? parse_info->flags().is_eval()
? RuntimeCallCounterId::kCompileBackgroundEval
: RuntimeCallCounterId::kCompileBackgroundScript
: RuntimeCallCounterId::kCompileBackgroundFunction);
// Generate the unoptimized bytecode or asm-js data.
DCHECK(inner_function_jobs->empty());
// TODO(leszeks): Once we can handle asm-js without bailing out of
// off-thread finalization entirely, and the finalization is off-thread by
// default, this can be changed to the iterative version.
std::unique_ptr<UnoptimizedCompilationJob> outer_function_job =
RecursivelyExecuteUnoptimizedCompilationJobs(
parse_info, parse_info->literal(), allocator, inner_function_jobs);
// Character stream shouldn't be used again.
parse_info->ResetCharacterStream();
return outer_function_job;
}
MaybeHandle<SharedFunctionInfo> CompileToplevel(
ParseInfo* parse_info, Handle<Script> script, Isolate* isolate,
IsCompiledScope* is_compiled_scope) {
return CompileToplevel(parse_info, script, kNullMaybeHandle, isolate,
is_compiled_scope);
}
} // namespace
BackgroundCompileTask::BackgroundCompileTask(ScriptStreamingData* streamed_data,
Isolate* isolate)
: flags_(UnoptimizedCompileFlags::ForToplevelCompile(
isolate, true, construct_language_mode(FLAG_use_strict),
REPLMode::kNo)),
compile_state_(isolate),
info_(std::make_unique<ParseInfo>(isolate, flags_, &compile_state_)),
start_position_(0),
end_position_(0),
function_literal_id_(kFunctionLiteralIdTopLevel),
stack_size_(i::FLAG_stack_size),
worker_thread_runtime_call_stats_(
isolate->counters()->worker_thread_runtime_call_stats()),
timer_(isolate->counters()->compile_script_on_background()),
language_mode_(info_->language_mode()) {
VMState<PARSER> state(isolate);
// Prepare the data for the internalization phase and compilation phase, which
// will happen in the main thread after parsing.
LOG(isolate, ScriptEvent(Logger::ScriptEventType::kStreamingCompile,
info_->flags().script_id()));
std::unique_ptr<Utf16CharacterStream> stream(ScannerStream::For(
streamed_data->source_stream.get(), streamed_data->encoding));
info_->set_character_stream(std::move(stream));
// TODO(leszeks): Add block coverage support to off-thread finalization.
finalize_on_background_thread_ =
FLAG_finalize_streaming_on_background && !flags_.block_coverage_enabled();
if (finalize_on_background_thread()) {
off_thread_isolate_ =
std::make_unique<OffThreadIsolate>(isolate, info_->zone());
}
}
BackgroundCompileTask::BackgroundCompileTask(
const ParseInfo* outer_parse_info, const AstRawString* function_name,
const FunctionLiteral* function_literal,
WorkerThreadRuntimeCallStats* worker_thread_runtime_stats,
TimedHistogram* timer, int max_stack_size)
: flags_(UnoptimizedCompileFlags::ForToplevelFunction(
outer_parse_info->flags(), function_literal)),
compile_state_(*outer_parse_info->state()),
info_(ParseInfo::ForToplevelFunction(flags_, &compile_state_,
function_literal, function_name)),
start_position_(function_literal->start_position()),
end_position_(function_literal->end_position()),
function_literal_id_(function_literal->function_literal_id()),
stack_size_(max_stack_size),
worker_thread_runtime_call_stats_(worker_thread_runtime_stats),
timer_(timer),
language_mode_(info_->language_mode()),
finalize_on_background_thread_(false) {
DCHECK_EQ(outer_parse_info->parameters_end_pos(), kNoSourcePosition);
DCHECK_NULL(outer_parse_info->extension());
DCHECK(!function_literal->is_toplevel());
// Clone the character stream so both can be accessed independently.
std::unique_ptr<Utf16CharacterStream> character_stream =
outer_parse_info->character_stream()->Clone();
character_stream->Seek(start_position_);
info_->set_character_stream(std::move(character_stream));
// Get preparsed scope data from the function literal.
if (function_literal->produced_preparse_data()) {
ZonePreparseData* serialized_data =
function_literal->produced_preparse_data()->Serialize(info_->zone());
info_->set_consumed_preparse_data(
ConsumedPreparseData::For(info_->zone(), serialized_data));
}
}
BackgroundCompileTask::~BackgroundCompileTask() = default;
namespace {
// A scope object that ensures a parse info's runtime call stats and stack limit
// are set correctly during worker-thread compile, and restores it after going
// out of scope.
class OffThreadParseInfoScope {
public:
OffThreadParseInfoScope(
ParseInfo* parse_info,
WorkerThreadRuntimeCallStats* worker_thread_runtime_stats, int stack_size)
: parse_info_(parse_info),
original_runtime_call_stats_(parse_info_->runtime_call_stats()),
original_stack_limit_(parse_info_->stack_limit()),
worker_thread_scope_(worker_thread_runtime_stats) {
parse_info_->SetPerThreadState(GetCurrentStackPosition() - stack_size * KB,
worker_thread_scope_.Get());
}
~OffThreadParseInfoScope() {
DCHECK_NOT_NULL(parse_info_);
parse_info_->SetPerThreadState(original_stack_limit_,
original_runtime_call_stats_);
}
private:
ParseInfo* parse_info_;
RuntimeCallStats* original_runtime_call_stats_;
uintptr_t original_stack_limit_;
WorkerThreadRuntimeCallStatsScope worker_thread_scope_;
DISALLOW_COPY_AND_ASSIGN(OffThreadParseInfoScope);
};
bool CanOffThreadFinalizeAllJobs(
UnoptimizedCompilationJob* outer_job,
const UnoptimizedCompilationJobList& inner_function_jobs) {
if (!outer_job->can_off_thread_finalize()) return false;
for (auto& job : inner_function_jobs) {
if (!job->can_off_thread_finalize()) {
return false;
}
}
return true;
}
} // namespace
void BackgroundCompileTask::Run() {
DisallowHeapAllocation no_allocation;
DisallowHandleAllocation no_handles;
DisallowHeapAccess no_heap_access;
TimedHistogramScope timer(timer_);
base::Optional<OffThreadParseInfoScope> off_thread_scope(
base::in_place, info_.get(), worker_thread_runtime_call_stats_,
stack_size_);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"BackgroundCompileTask::Run");
RuntimeCallTimerScope runtimeTimer(
info_->runtime_call_stats(),
RuntimeCallCounterId::kCompileBackgroundCompileTask);
// Update the character stream's runtime call stats.
info_->character_stream()->set_runtime_call_stats(
info_->runtime_call_stats());
// Parser needs to stay alive for finalizing the parsing on the main
// thread.
parser_.reset(new Parser(info_.get()));
parser_->InitializeEmptyScopeChain(info_.get());
parser_->ParseOnBackground(info_.get(), start_position_, end_position_,
function_literal_id_);
if (info_->literal() != nullptr) {
// Parsing has succeeded, compile.
outer_function_job_ = CompileOnBackgroundThread(
info_.get(), compile_state_.allocator(), &inner_function_jobs_);
}
// Save the language mode and record whether we collected source positions.
language_mode_ = info_->language_mode();
// We don't currently support off-thread finalization for some jobs (namely,
// asm.js), so release the off-thread isolate and fall back to main-thread
// finalization.
// TODO(leszeks): Still finalize Ignition tasks on the background thread,
// and fallback to main-thread finalization for asm.js jobs only.
finalize_on_background_thread_ =
finalize_on_background_thread_ && outer_function_job_ &&
CanOffThreadFinalizeAllJobs(outer_function_job(), *inner_function_jobs());
if (!finalize_on_background_thread_) {
off_thread_isolate_.reset();
return;
}
// ---
// At this point, off-thread compilation has completed and we are off-thread
// finalizing.
// ---
DCHECK(info_->flags().is_toplevel());
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.FinalizeCodeBackground");
OffThreadIsolate* isolate = off_thread_isolate();
isolate->PinToCurrentThread();
OffThreadHandleScope handle_scope(isolate);
// We don't have the script source, origin, or details yet, so use default
// values for them. These will be fixed up during the main-thread merge.
Handle<Script> script =
info_->CreateScript(isolate, isolate->factory()->empty_string(),
kNullMaybeHandle, ScriptOriginOptions());
MaybeHandle<SharedFunctionInfo> maybe_result;
if (info_->literal() != nullptr) {
info_->ast_value_factory()->Internalize(isolate);
Handle<SharedFunctionInfo> shared_info =
CreateTopLevelSharedFunctionInfo(info_.get(), script, isolate);
if (FinalizeAllUnoptimizedCompilationJobs(
info_.get(), isolate, shared_info, outer_function_job_.get(),
&inner_function_jobs_, &finalize_unoptimized_compilation_data_)) {
maybe_result = shared_info;
}
parser_->HandleSourceURLComments(isolate, script);
} else {
DCHECK(!outer_function_job_);
}
Handle<SharedFunctionInfo> result;
if (!maybe_result.ToHandle(&result)) {
DCHECK(compile_state_.pending_error_handler()->has_pending_error());
PreparePendingException(isolate, info_.get());
}
outer_function_sfi_ = isolate->TransferHandle(maybe_result);
script_ = isolate->TransferHandle(script);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.FinalizeCodeBackground.Finish");
isolate->FinishOffThread();
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.FinalizeCodeBackground.ReleaseParser");
DCHECK_EQ(language_mode_, info_->language_mode());
off_thread_scope.reset();
parser_.reset();
info_.reset();
outer_function_job_.reset();
inner_function_jobs_.clear();
}
// ----------------------------------------------------------------------------
// Implementation of Compiler
// static
bool Compiler::CollectSourcePositions(Isolate* isolate,
Handle<SharedFunctionInfo> shared_info) {
DCHECK(shared_info->is_compiled());
DCHECK(shared_info->HasBytecodeArray());
DCHECK(!shared_info->GetBytecodeArray().HasSourcePositionTable());
// Source position collection should be context independent.
NullContextScope null_context_scope(isolate);
// Collecting source positions requires allocating a new source position
// table.
DCHECK(AllowHeapAllocation::IsAllowed());
Handle<BytecodeArray> bytecode =
handle(shared_info->GetBytecodeArray(), isolate);
// TODO(v8:8510): Push the CLEAR_EXCEPTION flag or something like it down into
// the parser so it aborts without setting a pending exception, which then
// gets thrown. This would avoid the situation where potentially we'd reparse
// several times (running out of stack each time) before hitting this limit.
if (GetCurrentStackPosition() < isolate->stack_guard()->real_climit()) {
// Stack is already exhausted.
bytecode->SetSourcePositionsFailedToCollect();
return false;
}
DCHECK(AllowCompilation::IsAllowed(isolate));
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
DCHECK(!isolate->has_pending_exception());
VMState<BYTECODE_COMPILER> state(isolate);
PostponeInterruptsScope postpone(isolate);
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kCompileCollectSourcePositions);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CollectSourcePositions");
HistogramTimerScope timer(isolate->counters()->collect_source_positions());
// Set up parse info.
UnoptimizedCompileFlags flags =
UnoptimizedCompileFlags::ForFunctionCompile(isolate, *shared_info);
flags.set_is_lazy_compile(true);
flags.set_collect_source_positions(true);
flags.set_allow_natives_syntax(FLAG_allow_natives_syntax);
UnoptimizedCompileState compile_state(isolate);
ParseInfo parse_info(isolate, flags, &compile_state);
// Parse and update ParseInfo with the results. Don't update parsing
// statistics since we've already parsed the code before.
if (!parsing::ParseAny(&parse_info, shared_info, isolate,
parsing::ReportErrorsAndStatisticsMode::kNo)) {
// Parsing failed probably as a result of stack exhaustion.
bytecode->SetSourcePositionsFailedToCollect();
return FailAndClearPendingException(isolate);
}
// Character stream shouldn't be used again.
parse_info.ResetCharacterStream();
// Generate the unoptimized bytecode.
// TODO(v8:8510): Consider forcing preparsing of inner functions to avoid
// wasting time fully parsing them when they won't ever be used.
std::unique_ptr<UnoptimizedCompilationJob> job;
{
job = interpreter::Interpreter::NewSourcePositionCollectionJob(
&parse_info, parse_info.literal(), bytecode, isolate->allocator());
if (!job || job->ExecuteJob() != CompilationJob::SUCCEEDED ||
job->FinalizeJob(shared_info, isolate) != CompilationJob::SUCCEEDED) {
// Recompiling failed probably as a result of stack exhaustion.
bytecode->SetSourcePositionsFailedToCollect();
return FailAndClearPendingException(isolate);
}
}
DCHECK(job->compilation_info()->flags().collect_source_positions());
// If debugging, make sure that instrumented bytecode has the source position
// table set on it as well.
if (shared_info->HasDebugInfo() &&
shared_info->GetDebugInfo().HasInstrumentedBytecodeArray()) {
ByteArray source_position_table =
job->compilation_info()->bytecode_array()->SourcePositionTable();
shared_info->GetDebugBytecodeArray().set_source_position_table(
source_position_table);
}
DCHECK(!isolate->has_pending_exception());
DCHECK(shared_info->is_compiled_scope().is_compiled());
return true;
}
bool Compiler::Compile(Handle<SharedFunctionInfo> shared_info,
ClearExceptionFlag flag,
IsCompiledScope* is_compiled_scope) {
// We should never reach here if the function is already compiled.
DCHECK(!shared_info->is_compiled());
DCHECK(!is_compiled_scope->is_compiled());
Isolate* isolate = shared_info->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
DCHECK(!isolate->has_pending_exception());
DCHECK(!shared_info->HasBytecodeArray());
VMState<BYTECODE_COMPILER> state(isolate);
PostponeInterruptsScope postpone(isolate);
TimerEventScope<TimerEventCompileCode> compile_timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate,
RuntimeCallCounterId::kCompileFunction);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileCode");
AggregatedHistogramTimerScope timer(isolate->counters()->compile_lazy());
Handle<Script> script(Script::cast(shared_info->script()), isolate);
// Set up parse info.
UnoptimizedCompileFlags flags =
UnoptimizedCompileFlags::ForFunctionCompile(isolate, *shared_info);
flags.set_is_lazy_compile(true);
UnoptimizedCompileState compile_state(isolate);
ParseInfo parse_info(isolate, flags, &compile_state);
// Check if the compiler dispatcher has shared_info enqueued for compile.
CompilerDispatcher* dispatcher = isolate->compiler_dispatcher();
if (dispatcher->IsEnqueued(shared_info)) {
if (!dispatcher->FinishNow(shared_info)) {
return FailWithPendingException(isolate, script, &parse_info, flag);
}
*is_compiled_scope = shared_info->is_compiled_scope();
DCHECK(is_compiled_scope->is_compiled());
return true;
}
if (shared_info->HasUncompiledDataWithPreparseData()) {
parse_info.set_consumed_preparse_data(ConsumedPreparseData::For(
isolate,
handle(
shared_info->uncompiled_data_with_preparse_data().preparse_data(),
isolate)));
}
// Parse and update ParseInfo with the results.
if (!parsing::ParseAny(&parse_info, shared_info, isolate)) {
return FailWithPendingException(isolate, script, &parse_info, flag);
}
// Generate the unoptimized bytecode or asm-js data.
FinalizeUnoptimizedCompilationDataList
finalize_unoptimized_compilation_data_list;
if (!IterativelyExecuteAndFinalizeUnoptimizedCompilationJobs(
isolate, shared_info, script, &parse_info, isolate->allocator(),
is_compiled_scope, &finalize_unoptimized_compilation_data_list)) {
return FailWithPendingException(isolate, script, &parse_info, flag);
}
FinalizeUnoptimizedCompilation(isolate, script, flags, &compile_state,
finalize_unoptimized_compilation_data_list);
DCHECK(!isolate->has_pending_exception());
DCHECK(is_compiled_scope->is_compiled());
return true;
}
bool Compiler::Compile(Handle<JSFunction> function, ClearExceptionFlag flag,
IsCompiledScope* is_compiled_scope) {
// We should never reach here if the function is already compiled or optimized
DCHECK(!function->is_compiled());
DCHECK(!function->IsOptimized());
DCHECK(!function->HasOptimizationMarker());
DCHECK(!function->HasOptimizedCode());
// Reset the JSFunction if we are recompiling due to the bytecode having been
// flushed.
function->ResetIfBytecodeFlushed();
Isolate* isolate = function->GetIsolate();
Handle<SharedFunctionInfo> shared_info = handle(function->shared(), isolate);
// Ensure shared function info is compiled.
*is_compiled_scope = shared_info->is_compiled_scope();
if (!is_compiled_scope->is_compiled() &&
!Compile(shared_info, flag, is_compiled_scope)) {
return false;
}
DCHECK(is_compiled_scope->is_compiled());
Handle<Code> code = handle(shared_info->GetCode(), isolate);
// Initialize the feedback cell for this JSFunction.
JSFunction::InitializeFeedbackCell(function, is_compiled_scope);
// Optimize now if --always-opt is enabled.
if (FLAG_always_opt && !function->shared().HasAsmWasmData()) {
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[optimizing ");
function->ShortPrint(scope.file());
PrintF(scope.file(), " because --always-opt]\n");
}
Handle<Code> opt_code;
if (GetOptimizedCode(function, ConcurrencyMode::kNotConcurrent)
.ToHandle(&opt_code)) {
code = opt_code;
}
}
// Install code on closure.
function->set_code(*code);
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared().is_compiled());
DCHECK(function->is_compiled());
return true;
}
bool Compiler::FinalizeBackgroundCompileTask(
BackgroundCompileTask* task, Handle<SharedFunctionInfo> shared_info,
Isolate* isolate, ClearExceptionFlag flag) {
DCHECK(!task->finalize_on_background_thread());
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.FinalizeBackgroundCompileTask");
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kCompileFinalizeBackgroundCompileTask);
HandleScope scope(isolate);
ParseInfo* parse_info = task->info();
DCHECK(!parse_info->flags().is_toplevel());
DCHECK(!shared_info->is_compiled());
Handle<Script> script(Script::cast(shared_info->script()), isolate);
parse_info->CheckFlagsForFunctionFromScript(*script);
task->parser()->UpdateStatistics(isolate, script);
task->parser()->HandleSourceURLComments(isolate, script);
if (parse_info->literal() == nullptr || !task->outer_function_job()) {
// Parsing or compile failed on background thread - report error messages.
return FailWithPendingException(isolate, script, parse_info, flag);
}
// Parsing has succeeded - finalize compilation.
parse_info->ast_value_factory()->Internalize(isolate);
if (!FinalizeAllUnoptimizedCompilationJobs(
parse_info, isolate, shared_info, task->outer_function_job(),
task->inner_function_jobs(),
task->finalize_unoptimized_compilation_data())) {
// Finalization failed - throw an exception.
return FailWithPendingException(isolate, script, parse_info, flag);
}
FinalizeUnoptimizedCompilation(
isolate, script, parse_info->flags(), parse_info->state(),
*task->finalize_unoptimized_compilation_data());
DCHECK(!isolate->has_pending_exception());
DCHECK(shared_info->is_compiled());
return true;
}
bool Compiler::CompileOptimized(Handle<JSFunction> function,
ConcurrencyMode mode) {
if (function->IsOptimized()) return true;
Isolate* isolate = function->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// Start a compilation.
Handle<Code> code;
if (!GetOptimizedCode(function, mode).ToHandle(&code)) {
// Optimization failed, get unoptimized code. Unoptimized code must exist
// already if we are optimizing.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared().is_compiled());
DCHECK(function->shared().IsInterpreted());
code = BUILTIN_CODE(isolate, InterpreterEntryTrampoline);
}
// Install code on closure.
function->set_code(*code);
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared().is_compiled());
DCHECK(function->is_compiled());
DCHECK_IMPLIES(function->HasOptimizationMarker(),
function->IsInOptimizationQueue());
DCHECK_IMPLIES(function->HasOptimizationMarker(),
function->ChecksOptimizationMarker());
DCHECK_IMPLIES(function->IsInOptimizationQueue(),
mode == ConcurrencyMode::kConcurrent);
return true;
}
MaybeHandle<SharedFunctionInfo> Compiler::CompileForLiveEdit(
ParseInfo* parse_info, Handle<Script> script, Isolate* isolate) {
IsCompiledScope is_compiled_scope;
return CompileToplevel(parse_info, script, isolate, &is_compiled_scope);
}
MaybeHandle<JSFunction> Compiler::GetFunctionFromEval(
Handle<String> source, Handle<SharedFunctionInfo> outer_info,
Handle<Context> context, LanguageMode language_mode,
ParseRestriction restriction, int parameters_end_pos,
int eval_scope_position, int eval_position) {
Isolate* isolate = context->GetIsolate();
int source_length = source->length();
isolate->counters()->total_eval_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
// The cache lookup key needs to be aware of the separation between the
// parameters and the body to prevent this valid invocation:
// Function("", "function anonymous(\n/**/) {\n}");
// from adding an entry that falsely approves this invalid invocation:
// Function("\n/**/) {\nfunction anonymous(", "}");
// The actual eval_scope_position for indirect eval and CreateDynamicFunction
// is unused (just 0), which means it's an available field to use to indicate
// this separation. But to make sure we're not causing other false hits, we
// negate the scope position.
if (restriction == ONLY_SINGLE_FUNCTION_LITERAL &&
parameters_end_pos != kNoSourcePosition) {
// use the parameters_end_pos as the eval_scope_position in the eval cache.
DCHECK_EQ(eval_scope_position, 0);
eval_scope_position = -parameters_end_pos;
}
CompilationCache* compilation_cache = isolate->compilation_cache();
InfoCellPair eval_result = compilation_cache->LookupEval(
source, outer_info, context, language_mode, eval_scope_position);
Handle<FeedbackCell> feedback_cell;
if (eval_result.has_feedback_cell()) {
feedback_cell = handle(eval_result.feedback_cell(), isolate);
}
Handle<SharedFunctionInfo> shared_info;
Handle<Script> script;
IsCompiledScope is_compiled_scope;
bool allow_eval_cache;
if (eval_result.has_shared()) {
shared_info = Handle<SharedFunctionInfo>(eval_result.shared(), isolate);
script = Handle<Script>(Script::cast(shared_info->script()), isolate);
is_compiled_scope = shared_info->is_compiled_scope();
allow_eval_cache = true;
} else {
UnoptimizedCompileFlags flags = UnoptimizedCompileFlags::ForToplevelCompile(
isolate, true, language_mode, REPLMode::kNo);
flags.set_is_eval(true);
flags.set_parse_restriction(restriction);
UnoptimizedCompileState compile_state(isolate);
ParseInfo parse_info(isolate, flags, &compile_state);
parse_info.set_parameters_end_pos(parameters_end_pos);
DCHECK(!parse_info.flags().is_module());
MaybeHandle<ScopeInfo> maybe_outer_scope_info;
if (!context->IsNativeContext()) {
maybe_outer_scope_info = handle(context->scope_info(), isolate);
}
script =
parse_info.CreateScript(isolate, source, kNullMaybeHandle,
OriginOptionsForEval(outer_info->script()));
script->set_eval_from_shared(*outer_info);
if (eval_position == kNoSourcePosition) {
// If the position is missing, attempt to get the code offset by
// walking the stack. Do not translate the code offset into source
// position, but store it as negative value for lazy translation.
StackTraceFrameIterator it(isolate);
if (!it.done() && it.is_javascript()) {
FrameSummary summary = FrameSummary::GetTop(it.javascript_frame());
script->set_eval_from_shared(
summary.AsJavaScript().function()->shared());
script->set_origin_options(OriginOptionsForEval(*summary.script()));
eval_position = -summary.code_offset();
} else {
eval_position = 0;
}
}
script->set_eval_from_position(eval_position);
if (!CompileToplevel(&parse_info, script, maybe_outer_scope_info, isolate,
&is_compiled_scope)
.ToHandle(&shared_info)) {
return MaybeHandle<JSFunction>();
}
allow_eval_cache = parse_info.allow_eval_cache();
}
// If caller is strict mode, the result must be in strict mode as well.
DCHECK(is_sloppy(language_mode) || is_strict(shared_info->language_mode()));
Handle<JSFunction> result;
if (eval_result.has_shared()) {
if (eval_result.has_feedback_cell()) {
result = isolate->factory()->NewFunctionFromSharedFunctionInfo(
shared_info, context, feedback_cell, AllocationType::kYoung);
} else {
result = isolate->factory()->NewFunctionFromSharedFunctionInfo(
shared_info, context, AllocationType::kYoung);
JSFunction::InitializeFeedbackCell(result, &is_compiled_scope);
if (allow_eval_cache) {
// Make sure to cache this result.
Handle<FeedbackCell> new_feedback_cell(result->raw_feedback_cell(),
isolate);
compilation_cache->PutEval(source, outer_info, context, shared_info,
new_feedback_cell, eval_scope_position);
}
}
} else {
result = isolate->factory()->NewFunctionFromSharedFunctionInfo(
shared_info, context, AllocationType::kYoung);
JSFunction::InitializeFeedbackCell(result, &is_compiled_scope);
if (allow_eval_cache) {
// Add the SharedFunctionInfo and the LiteralsArray to the eval cache if
// we didn't retrieve from there.
Handle<FeedbackCell> new_feedback_cell(result->raw_feedback_cell(),
isolate);
compilation_cache->PutEval(source, outer_info, context, shared_info,
new_feedback_cell, eval_scope_position);
}
}
DCHECK(is_compiled_scope.is_compiled());
return result;
}
// Check whether embedder allows code generation in this context.
// (via v8::Isolate::SetAllowCodeGenerationFromStringsCallback)
bool CodeGenerationFromStringsAllowed(Isolate* isolate, Handle<Context> context,
Handle<String> source) {
DCHECK(context->allow_code_gen_from_strings().IsFalse(isolate));
DCHECK(isolate->allow_code_gen_callback());
// Callback set. Let it decide if code generation is allowed.
VMState<EXTERNAL> state(isolate);
RuntimeCallTimerScope timer(
isolate, RuntimeCallCounterId::kCodeGenerationFromStringsCallbacks);
AllowCodeGenerationFromStringsCallback callback =
isolate->allow_code_gen_callback();
return callback(v8::Utils::ToLocal(context), v8::Utils::ToLocal(source));
}
// Check whether embedder allows code generation in this context.
// (via v8::Isolate::SetModifyCodeGenerationFromStringsCallback)
bool ModifyCodeGenerationFromStrings(Isolate* isolate, Handle<Context> context,
Handle<i::Object>* source) {
DCHECK(isolate->modify_code_gen_callback());
DCHECK(source);
// Callback set. Run it, and use the return value as source, or block
// execution if it's not set.
VMState<EXTERNAL> state(isolate);
ModifyCodeGenerationFromStringsCallback modify_callback =
isolate->modify_code_gen_callback();
RuntimeCallTimerScope timer(
isolate, RuntimeCallCounterId::kCodeGenerationFromStringsCallbacks);
ModifyCodeGenerationFromStringsResult result =
modify_callback(v8::Utils::ToLocal(context), v8::Utils::ToLocal(*source));
if (result.codegen_allowed && !result.modified_source.IsEmpty()) {
// Use the new source (which might be the same as the old source).
*source =
Utils::OpenHandle(*result.modified_source.ToLocalChecked(), false);
}
return result.codegen_allowed;
}
// Run Embedder-mandated checks before generating code from a string.
//
// Returns a string to be used for compilation, or a flag that an object type
// was encountered that is neither a string, nor something the embedder knows
// how to handle.
//
// Returns: (assuming: std::tie(source, unknown_object))
// - !source.is_null(): compilation allowed, source contains the source string.
// - unknown_object is true: compilation allowed, but we don't know how to
// deal with source_object.
// - source.is_null() && !unknown_object: compilation should be blocked.
//
// - !source_is_null() and unknown_object can't be true at the same time.
std::pair<MaybeHandle<String>, bool> Compiler::ValidateDynamicCompilationSource(
Isolate* isolate, Handle<Context> context,
Handle<i::Object> original_source) {
// Check if the context unconditionally allows code gen from strings.
// allow_code_gen_from_strings can be many things, so we'll always check
// against the 'false' literal, so that e.g. undefined and 'true' are treated
// the same.
if (!context->allow_code_gen_from_strings().IsFalse(isolate) &&
original_source->IsString()) {
return {Handle<String>::cast(original_source), false};
}
// Check if the context allows code generation for this string.
// allow_code_gen_callback only allows proper strings.
// (I.e., let allow_code_gen_callback decide, if it has been set.)
if (isolate->allow_code_gen_callback()) {
if (!original_source->IsString()) {
return {MaybeHandle<String>(), true};
}
Handle<String> string_source = Handle<String>::cast(original_source);
if (!CodeGenerationFromStringsAllowed(isolate, context, string_source)) {
return {MaybeHandle<String>(), false};
}
return {string_source, false};
}
// Check if the context wants to block or modify this source object.
// Double-check that we really have a string now.
// (Let modify_code_gen_callback decide, if it's been set.)
if (isolate->modify_code_gen_callback()) {
Handle<i::Object> modified_source = original_source;
if (!ModifyCodeGenerationFromStrings(isolate, context, &modified_source)) {
return {MaybeHandle<String>(), false};
}
if (!modified_source->IsString()) {
return {MaybeHandle<String>(), true};
}
return {Handle<String>::cast(modified_source), false};
}
// If unconditional codegen was disabled, and no callback defined, we block
// strings and allow all other objects.
return {MaybeHandle<String>(), !original_source->IsString()};
}
MaybeHandle<JSFunction> Compiler::GetFunctionFromValidatedString(
Handle<Context> context, MaybeHandle<String> source,
ParseRestriction restriction, int parameters_end_pos) {
Isolate* const isolate = context->GetIsolate();
Handle<Context> native_context(context->native_context(), isolate);
// Raise an EvalError if we did not receive a string.
if (source.is_null()) {
Handle<Object> error_message =
native_context->ErrorMessageForCodeGenerationFromStrings();
THROW_NEW_ERROR(
isolate,
NewEvalError(MessageTemplate::kCodeGenFromStrings, error_message),
JSFunction);
}
// Compile source string in the native context.
int eval_scope_position = 0;
int eval_position = kNoSourcePosition;
Handle<SharedFunctionInfo> outer_info(
native_context->empty_function().shared(), isolate);
return Compiler::GetFunctionFromEval(source.ToHandleChecked(), outer_info,
native_context, LanguageMode::kSloppy,
restriction, parameters_end_pos,
eval_scope_position, eval_position);
}
MaybeHandle<JSFunction> Compiler::GetFunctionFromString(
Handle<Context> context, Handle<Object> source,
ParseRestriction restriction, int parameters_end_pos) {
Isolate* const isolate = context->GetIsolate();
Handle<Context> native_context(context->native_context(), isolate);
return GetFunctionFromValidatedString(
context, ValidateDynamicCompilationSource(isolate, context, source).first,
restriction, parameters_end_pos);
}
namespace {
struct ScriptCompileTimerScope {
public:
// TODO(leszeks): There are too many blink-specific entries in this enum,
// figure out a way to push produce/hit-isolate-cache/consume/consume-failed
// back up the API and log them in blink instead.
enum class CacheBehaviour {
kProduceCodeCache,
kHitIsolateCacheWhenNoCache,
kConsumeCodeCache,
kConsumeCodeCacheFailed,
kNoCacheBecauseInlineScript,
kNoCacheBecauseScriptTooSmall,
kNoCacheBecauseCacheTooCold,
kNoCacheNoReason,
kNoCacheBecauseNoResource,
kNoCacheBecauseInspector,
kNoCacheBecauseCachingDisabled,
kNoCacheBecauseModule,
kNoCacheBecauseStreamingSource,
kNoCacheBecauseV8Extension,
kHitIsolateCacheWhenProduceCodeCache,
kHitIsolateCacheWhenConsumeCodeCache,
kNoCacheBecauseExtensionModule,
kNoCacheBecausePacScript,
kNoCacheBecauseInDocumentWrite,
kNoCacheBecauseResourceWithNoCacheHandler,
kHitIsolateCacheWhenStreamingSource,
kCount
};
explicit ScriptCompileTimerScope(
Isolate* isolate, ScriptCompiler::NoCacheReason no_cache_reason)
: isolate_(isolate),
all_scripts_histogram_scope_(isolate->counters()->compile_script(),
true),
no_cache_reason_(no_cache_reason),
hit_isolate_cache_(false),
producing_code_cache_(false),
consuming_code_cache_(false),
consuming_code_cache_failed_(false) {}
~ScriptCompileTimerScope() {
CacheBehaviour cache_behaviour = GetCacheBehaviour();
Histogram* cache_behaviour_histogram =
isolate_->counters()->compile_script_cache_behaviour();
// Sanity check that the histogram has exactly one bin per enum entry.
DCHECK_EQ(0, cache_behaviour_histogram->min());
DCHECK_EQ(static_cast<int>(CacheBehaviour::kCount),
cache_behaviour_histogram->max() + 1);
DCHECK_EQ(static_cast<int>(CacheBehaviour::kCount),
cache_behaviour_histogram->num_buckets());
cache_behaviour_histogram->AddSample(static_cast<int>(cache_behaviour));
histogram_scope_.set_histogram(
GetCacheBehaviourTimedHistogram(cache_behaviour));
}
void set_hit_isolate_cache() { hit_isolate_cache_ = true; }
void set_producing_code_cache() { producing_code_cache_ = true; }
void set_consuming_code_cache() { consuming_code_cache_ = true; }
void set_consuming_code_cache_failed() {
consuming_code_cache_failed_ = true;
}
private:
Isolate* isolate_;
LazyTimedHistogramScope histogram_scope_;
// TODO(leszeks): This timer is the sum of the other times, consider removing
// it to save space.
HistogramTimerScope all_scripts_histogram_scope_;
ScriptCompiler::NoCacheReason no_cache_reason_;
bool hit_isolate_cache_;
bool producing_code_cache_;
bool consuming_code_cache_;
bool consuming_code_cache_failed_;
CacheBehaviour GetCacheBehaviour() {
if (producing_code_cache_) {
if (hit_isolate_cache_) {
return CacheBehaviour::kHitIsolateCacheWhenProduceCodeCache;
} else {
return CacheBehaviour::kProduceCodeCache;
}
}
if (consuming_code_cache_) {
if (hit_isolate_cache_) {
return CacheBehaviour::kHitIsolateCacheWhenConsumeCodeCache;
} else if (consuming_code_cache_failed_) {
return CacheBehaviour::kConsumeCodeCacheFailed;
}
return CacheBehaviour::kConsumeCodeCache;
}
if (hit_isolate_cache_) {
if (no_cache_reason_ == ScriptCompiler::kNoCacheBecauseStreamingSource) {
return CacheBehaviour::kHitIsolateCacheWhenStreamingSource;
}
return CacheBehaviour::kHitIsolateCacheWhenNoCache;
}
switch (no_cache_reason_) {
case ScriptCompiler::kNoCacheBecauseInlineScript:
return CacheBehaviour::kNoCacheBecauseInlineScript;
case ScriptCompiler::kNoCacheBecauseScriptTooSmall:
return CacheBehaviour::kNoCacheBecauseScriptTooSmall;
case ScriptCompiler::kNoCacheBecauseCacheTooCold:
return CacheBehaviour::kNoCacheBecauseCacheTooCold;
case ScriptCompiler::kNoCacheNoReason:
return CacheBehaviour::kNoCacheNoReason;
case ScriptCompiler::kNoCacheBecauseNoResource:
return CacheBehaviour::kNoCacheBecauseNoResource;
case ScriptCompiler::kNoCacheBecauseInspector:
return CacheBehaviour::kNoCacheBecauseInspector;
case ScriptCompiler::kNoCacheBecauseCachingDisabled:
return CacheBehaviour::kNoCacheBecauseCachingDisabled;
case ScriptCompiler::kNoCacheBecauseModule:
return CacheBehaviour::kNoCacheBecauseModule;
case ScriptCompiler::kNoCacheBecauseStreamingSource:
return CacheBehaviour::kNoCacheBecauseStreamingSource;
case ScriptCompiler::kNoCacheBecauseV8Extension:
return CacheBehaviour::kNoCacheBecauseV8Extension;
case ScriptCompiler::kNoCacheBecauseExtensionModule:
return CacheBehaviour::kNoCacheBecauseExtensionModule;
case ScriptCompiler::kNoCacheBecausePacScript:
return CacheBehaviour::kNoCacheBecausePacScript;
case ScriptCompiler::kNoCacheBecauseInDocumentWrite:
return CacheBehaviour::kNoCacheBecauseInDocumentWrite;
case ScriptCompiler::kNoCacheBecauseResourceWithNoCacheHandler:
return CacheBehaviour::kNoCacheBecauseResourceWithNoCacheHandler;
case ScriptCompiler::kNoCacheBecauseDeferredProduceCodeCache: {
if (hit_isolate_cache_) {
return CacheBehaviour::kHitIsolateCacheWhenProduceCodeCache;
} else {
return CacheBehaviour::kProduceCodeCache;
}
}
}
UNREACHABLE();
}
TimedHistogram* GetCacheBehaviourTimedHistogram(
CacheBehaviour cache_behaviour) {
switch (cache_behaviour) {
case CacheBehaviour::kProduceCodeCache:
// Even if we hit the isolate's compilation cache, we currently recompile
// when we want to produce the code cache.
case CacheBehaviour::kHitIsolateCacheWhenProduceCodeCache:
return isolate_->counters()->compile_script_with_produce_cache();
case CacheBehaviour::kHitIsolateCacheWhenNoCache:
case CacheBehaviour::kHitIsolateCacheWhenConsumeCodeCache:
case CacheBehaviour::kHitIsolateCacheWhenStreamingSource:
return isolate_->counters()->compile_script_with_isolate_cache_hit();
case CacheBehaviour::kConsumeCodeCacheFailed:
return isolate_->counters()->compile_script_consume_failed();
case CacheBehaviour::kConsumeCodeCache:
return isolate_->counters()->compile_script_with_consume_cache();
// Note that this only counts the finalization part of streaming, the
// actual streaming compile is counted by BackgroundCompileTask into
// "compile_script_on_background".
case CacheBehaviour::kNoCacheBecauseStreamingSource:
return isolate_->counters()->compile_script_streaming_finalization();
case CacheBehaviour::kNoCacheBecauseInlineScript:
return isolate_->counters()
->compile_script_no_cache_because_inline_script();
case CacheBehaviour::kNoCacheBecauseScriptTooSmall:
return isolate_->counters()
->compile_script_no_cache_because_script_too_small();
case CacheBehaviour::kNoCacheBecauseCacheTooCold:
return isolate_->counters()
->compile_script_no_cache_because_cache_too_cold();
// Aggregate all the other "no cache" counters into a single histogram, to
// save space.
case CacheBehaviour::kNoCacheNoReason:
case CacheBehaviour::kNoCacheBecauseNoResource:
case CacheBehaviour::kNoCacheBecauseInspector:
case CacheBehaviour::kNoCacheBecauseCachingDisabled:
// TODO(leszeks): Consider counting separately once modules are more
// common.
case CacheBehaviour::kNoCacheBecauseModule:
case CacheBehaviour::kNoCacheBecauseV8Extension:
case CacheBehaviour::kNoCacheBecauseExtensionModule:
case CacheBehaviour::kNoCacheBecausePacScript:
case CacheBehaviour::kNoCacheBecauseInDocumentWrite:
case CacheBehaviour::kNoCacheBecauseResourceWithNoCacheHandler:
return isolate_->counters()->compile_script_no_cache_other();
case CacheBehaviour::kCount:
UNREACHABLE();
}
UNREACHABLE();
}
};
void SetScriptFieldsFromDetails(Isolate* isolate, Script script,
Compiler::ScriptDetails script_details,
DisallowHeapAllocation* no_gc) {
Handle<Object> script_name;
if (script_details.name_obj.ToHandle(&script_name)) {
script.set_name(*script_name);
script.set_line_offset(script_details.line_offset);
script.set_column_offset(script_details.column_offset);
}
// The API can provide a source map URL, but a source map URL could also have
// been inferred by the parser from a magic comment. The latter takes
// preference over the former, so we don't want to override the source mapping
// URL if it already exists.
Handle<Object> source_map_url;
if (script_details.source_map_url.ToHandle(&source_map_url) &&
script.source_mapping_url(isolate).IsUndefined(isolate)) {
script.set_source_mapping_url(*source_map_url);
}
Handle<FixedArray> host_defined_options;
if (script_details.host_defined_options.ToHandle(&host_defined_options)) {
script.set_host_defined_options(*host_defined_options);
}
}
Handle<Script> NewScript(
Isolate* isolate, ParseInfo* parse_info, Handle<String> source,
Compiler::ScriptDetails script_details, ScriptOriginOptions origin_options,
NativesFlag natives,
MaybeHandle<FixedArray> maybe_wrapped_arguments = kNullMaybeHandle) {
// Create a script object describing the script to be compiled.
Handle<Script> script = parse_info->CreateScript(
isolate, source, maybe_wrapped_arguments, origin_options, natives);
DisallowHeapAllocation no_gc;
SetScriptFieldsFromDetails(isolate, *script, script_details, &no_gc);
LOG(isolate, ScriptDetails(*script));
return script;
}
MaybeHandle<SharedFunctionInfo> CompileScriptOnMainThread(
const UnoptimizedCompileFlags flags, Handle<String> source,
const Compiler::ScriptDetails& script_details,
ScriptOriginOptions origin_options, NativesFlag natives,
v8::Extension* extension, Isolate* isolate,
IsCompiledScope* is_compiled_scope) {
UnoptimizedCompileState compile_state(isolate);
ParseInfo parse_info(isolate, flags, &compile_state);
parse_info.set_extension(extension);
Handle<Script> script = NewScript(isolate, &parse_info, source,
script_details, origin_options, natives);
DCHECK_IMPLIES(parse_info.flags().collect_type_profile(),
script->IsUserJavaScript());
DCHECK_EQ(parse_info.flags().is_repl_mode(), script->is_repl_mode());
return CompileToplevel(&parse_info, script, isolate, is_compiled_scope);
}
class StressBackgroundCompileThread : public base::Thread {
public:
StressBackgroundCompileThread(Isolate* isolate, Handle<String> source)
: base::Thread(
base::Thread::Options("StressBackgroundCompileThread", 2 * i::MB)),
source_(source),
streamed_source_(std::make_unique<SourceStream>(source, isolate),
v8::ScriptCompiler::StreamedSource::UTF8) {
data()->task = std::make_unique<i::BackgroundCompileTask>(data(), isolate);
}
void Run() override { data()->task->Run(); }
ScriptStreamingData* data() { return streamed_source_.impl(); }
private:
// Dummy external source stream which returns the whole source in one go.
// TODO(leszeks): Also test chunking the data.
class SourceStream : public v8::ScriptCompiler::ExternalSourceStream {
public:
SourceStream(Handle<String> source, Isolate* isolate) : done_(false) {
source_buffer_ = source->ToCString(ALLOW_NULLS, FAST_STRING_TRAVERSAL,
&source_length_);
}
size_t GetMoreData(const uint8_t** src) override {
if (done_) {
return 0;
}
*src = reinterpret_cast<uint8_t*>(source_buffer_.release());
done_ = true;
return source_length_;
}
private:
int source_length_;
std::unique_ptr<char[]> source_buffer_;
bool done_;
};
Handle<String> source_;
v8::ScriptCompiler::StreamedSource streamed_source_;
};
bool CanBackgroundCompile(const Compiler::ScriptDetails& script_details,
ScriptOriginOptions origin_options,
v8::Extension* extension,
ScriptCompiler::CompileOptions compile_options,
NativesFlag natives) {
// TODO(leszeks): Remove the module check once background compilation of
// modules is supported.
return !origin_options.IsModule() && !extension &&
script_details.repl_mode == REPLMode::kNo &&
compile_options == ScriptCompiler::kNoCompileOptions &&
natives == NOT_NATIVES_CODE;
}
MaybeHandle<SharedFunctionInfo> CompileScriptOnBothBackgroundAndMainThread(
Handle<String> source, const Compiler::ScriptDetails& script_details,
ScriptOriginOptions origin_options, Isolate* isolate,
IsCompiledScope* is_compiled_scope) {
// Start a background thread compiling the script.
StressBackgroundCompileThread background_compile_thread(isolate, source);
UnoptimizedCompileFlags flags_copy =
background_compile_thread.data()->task->flags();
CHECK(background_compile_thread.Start());
MaybeHandle<SharedFunctionInfo> main_thread_maybe_result;
// In parallel, compile on the main thread to flush out any data races.
{
IsCompiledScope inner_is_compiled_scope;
// The background thread should also create any relevant exceptions, so we
// can ignore the main-thread created ones.
// TODO(leszeks): Maybe verify that any thrown (or unthrown) exceptions are
// equivalent.
TryCatch ignore_try_catch(reinterpret_cast<v8::Isolate*>(isolate));
flags_copy.set_script_id(Script::kTemporaryScriptId);
main_thread_maybe_result = CompileScriptOnMainThread(
flags_copy, source, script_details, origin_options, NOT_NATIVES_CODE,
nullptr, isolate, &inner_is_compiled_scope);
}
// Join with background thread and finalize compilation.
background_compile_thread.Join();
MaybeHandle<SharedFunctionInfo> maybe_result =
Compiler::GetSharedFunctionInfoForStreamedScript(
isolate, source, script_details, origin_options,
background_compile_thread.data());
// Either both compiles should succeed, or both should fail.
// TODO(leszeks): Compare the contents of the results of the two compiles.
CHECK_EQ(maybe_result.is_null(), main_thread_maybe_result.is_null());
Handle<SharedFunctionInfo> result;
if (maybe_result.ToHandle(&result)) {
*is_compiled_scope = result->is_compiled_scope();
}
return maybe_result;
}
} // namespace
MaybeHandle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
Isolate* isolate, Handle<String> source,
const Compiler::ScriptDetails& script_details,
ScriptOriginOptions origin_options, v8::Extension* extension,
ScriptData* cached_data, ScriptCompiler::CompileOptions compile_options,
ScriptCompiler::NoCacheReason no_cache_reason, NativesFlag natives) {
ScriptCompileTimerScope compile_timer(isolate, no_cache_reason);
if (compile_options == ScriptCompiler::kNoCompileOptions ||
compile_options == ScriptCompiler::kEagerCompile) {
DCHECK_NULL(cached_data);
} else {
DCHECK(compile_options == ScriptCompiler::kConsumeCodeCache);
DCHECK(cached_data);
DCHECK_NULL(extension);
}
int source_length = source->length();
isolate->counters()->total_load_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
LanguageMode language_mode = construct_language_mode(FLAG_use_strict);
CompilationCache* compilation_cache = isolate->compilation_cache();
// Do a lookup in the compilation cache but not for extensions.
MaybeHandle<SharedFunctionInfo> maybe_result;
IsCompiledScope is_compiled_scope;
if (extension == nullptr) {
bool can_consume_code_cache =
compile_options == ScriptCompiler::kConsumeCodeCache;
if (can_consume_code_cache) {
compile_timer.set_consuming_code_cache();
}
// First check per-isolate compilation cache.
maybe_result = compilation_cache->LookupScript(
source, script_details.name_obj, script_details.line_offset,
script_details.column_offset, origin_options, isolate->native_context(),
language_mode);
if (!maybe_result.is_null()) {
compile_timer.set_hit_isolate_cache();
} else if (can_consume_code_cache) {
compile_timer.set_consuming_code_cache();
// Then check cached code provided by embedder.
HistogramTimerScope timer(isolate->counters()->compile_deserialize());
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kCompileDeserialize);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CompileDeserialize");
Handle<SharedFunctionInfo> inner_result;
if (CodeSerializer::Deserialize(isolate, cached_data, source,
origin_options)
.ToHandle(&inner_result) &&
inner_result->is_compiled()) {
// Promote to per-isolate compilation cache.
is_compiled_scope = inner_result->is_compiled_scope();
DCHECK(is_compiled_scope.is_compiled());
compilation_cache->PutScript(source, isolate->native_context(),
language_mode, inner_result);
Handle<Script> script(Script::cast(inner_result->script()), isolate);
maybe_result = inner_result;
} else {
// Deserializer failed. Fall through to compile.
compile_timer.set_consuming_code_cache_failed();
}
}
}
if (maybe_result.is_null()) {
// No cache entry found compile the script.
if (FLAG_stress_background_compile &&
CanBackgroundCompile(script_details, origin_options, extension,
compile_options, natives)) {
// If the --stress-background-compile flag is set, do the actual
// compilation on a background thread, and wait for its result.
maybe_result = CompileScriptOnBothBackgroundAndMainThread(
source, script_details, origin_options, isolate, &is_compiled_scope);
} else {
UnoptimizedCompileFlags flags =
UnoptimizedCompileFlags::ForToplevelCompile(
isolate, natives == NOT_NATIVES_CODE, language_mode,
script_details.repl_mode);
flags.set_is_eager(compile_options == ScriptCompiler::kEagerCompile);
flags.set_is_module(origin_options.IsModule());
maybe_result = CompileScriptOnMainThread(
flags, source, script_details, origin_options, natives, extension,
isolate, &is_compiled_scope);
}
// Add the result to the isolate cache.
Handle<SharedFunctionInfo> result;
if (extension == nullptr && maybe_result.ToHandle(&result)) {
DCHECK(is_compiled_scope.is_compiled());
compilation_cache->PutScript(source, isolate->native_context(),
language_mode, result);
} else if (maybe_result.is_null() && natives != EXTENSION_CODE) {
isolate->ReportPendingMessages();
}
}
return maybe_result;
}
MaybeHandle<JSFunction> Compiler::GetWrappedFunction(
Handle<String> source, Handle<FixedArray> arguments,
Handle<Context> context, const Compiler::ScriptDetails& script_details,
ScriptOriginOptions origin_options, ScriptData* cached_data,
v8::ScriptCompiler::CompileOptions compile_options,
v8::ScriptCompiler::NoCacheReason no_cache_reason) {
Isolate* isolate = context->GetIsolate();
ScriptCompileTimerScope compile_timer(isolate, no_cache_reason);
if (compile_options == ScriptCompiler::kNoCompileOptions ||
compile_options == ScriptCompiler::kEagerCompile) {
DCHECK_NULL(cached_data);
} else {
DCHECK(compile_options == ScriptCompiler::kConsumeCodeCache);
DCHECK(cached_data);
}
int source_length = source->length();
isolate->counters()->total_compile_size()->Increment(source_length);
LanguageMode language_mode = construct_language_mode(FLAG_use_strict);
MaybeHandle<SharedFunctionInfo> maybe_result;
bool can_consume_code_cache =
compile_options == ScriptCompiler::kConsumeCodeCache;
if (can_consume_code_cache) {
compile_timer.set_consuming_code_cache();
// Then check cached code provided by embedder.
HistogramTimerScope timer(isolate->counters()->compile_deserialize());
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kCompileDeserialize);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CompileDeserialize");
maybe_result = CodeSerializer::Deserialize(isolate, cached_data, source,
origin_options);
if (maybe_result.is_null()) {
// Deserializer failed. Fall through to compile.
compile_timer.set_consuming_code_cache_failed();
}
}
Handle<SharedFunctionInfo> wrapped;
Handle<Script> script;
IsCompiledScope is_compiled_scope;
if (!maybe_result.ToHandle(&wrapped)) {
UnoptimizedCompileFlags flags = UnoptimizedCompileFlags::ForToplevelCompile(
isolate, true, language_mode, script_details.repl_mode);
flags.set_is_eval(true); // Use an eval scope as declaration scope.
flags.set_function_syntax_kind(FunctionSyntaxKind::kWrapped);
// TODO(delphick): Remove this and instead make the wrapped and wrapper
// functions fully non-lazy instead thus preventing source positions from
// being omitted.
flags.set_collect_source_positions(true);
// flags.set_eager(compile_options == ScriptCompiler::kEagerCompile);
UnoptimizedCompileState compile_state(isolate);
ParseInfo parse_info(isolate, flags, &compile_state);
MaybeHandle<ScopeInfo> maybe_outer_scope_info;
if (!context->IsNativeContext()) {
maybe_outer_scope_info = handle(context->scope_info(), isolate);
}
script = NewScript(isolate, &parse_info, source, script_details,
origin_options, NOT_NATIVES_CODE, arguments);
Handle<SharedFunctionInfo> top_level;
maybe_result = CompileToplevel(&parse_info, script, maybe_outer_scope_info,
isolate, &is_compiled_scope);
if (maybe_result.is_null()) isolate->ReportPendingMessages();
ASSIGN_RETURN_ON_EXCEPTION(isolate, top_level, maybe_result, JSFunction);
SharedFunctionInfo::ScriptIterator infos(isolate, *script);
for (SharedFunctionInfo info = infos.Next(); !info.is_null();
info = infos.Next()) {
if (info.is_wrapped()) {
wrapped = Handle<SharedFunctionInfo>(info, isolate);
break;
}
}
DCHECK(!wrapped.is_null());
} else {
is_compiled_scope = wrapped->is_compiled_scope();
script = Handle<Script>(Script::cast(wrapped->script()), isolate);
}
DCHECK(is_compiled_scope.is_compiled());
return isolate->factory()->NewFunctionFromSharedFunctionInfo(
wrapped, context, AllocationType::kYoung);
}
MaybeHandle<SharedFunctionInfo>
Compiler::GetSharedFunctionInfoForStreamedScript(
Isolate* isolate, Handle<String> source,
const ScriptDetails& script_details, ScriptOriginOptions origin_options,
ScriptStreamingData* streaming_data) {
DCHECK(!origin_options.IsModule());
DCHECK(!origin_options.IsWasm());
ScriptCompileTimerScope compile_timer(
isolate, ScriptCompiler::kNoCacheBecauseStreamingSource);
PostponeInterruptsScope postpone(isolate);
int source_length = source->length();
isolate->counters()->total_load_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
BackgroundCompileTask* task = streaming_data->task.get();
MaybeHandle<SharedFunctionInfo> maybe_result;
// Check if compile cache already holds the SFI, if so no need to finalize
// the code compiled on the background thread.
CompilationCache* compilation_cache = isolate->compilation_cache();
{
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.StreamingFinalization.CheckCache");
maybe_result = compilation_cache->LookupScript(
source, script_details.name_obj, script_details.line_offset,
script_details.column_offset, origin_options, isolate->native_context(),
task->language_mode());
if (!maybe_result.is_null()) {
compile_timer.set_hit_isolate_cache();
}
}
if (maybe_result.is_null()) {
// No cache entry found, finalize compilation of the script and add it to
// the isolate cache.
Handle<Script> script;
if (task->finalize_on_background_thread()) {
RuntimeCallTimerScope runtimeTimerScope(
isolate, RuntimeCallCounterId::kCompilePublishBackgroundFinalization);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.OffThreadFinalization.Publish");
task->off_thread_isolate()->Publish(isolate);
maybe_result = task->outer_function_sfi();
script = task->script();
script->set_source(*source);
script->set_origin_options(origin_options);
} else {
ParseInfo* parse_info = task->info();
DCHECK(parse_info->flags().is_toplevel());
script = parse_info->CreateScript(isolate, source, kNullMaybeHandle,
origin_options);
task->parser()->UpdateStatistics(isolate, script);
task->parser()->HandleSourceURLComments(isolate, script);
if (parse_info->literal() != nullptr && task->outer_function_job()) {
// Off-thread parse & compile has succeeded - finalize compilation.
parse_info->ast_value_factory()->Internalize(isolate);
Handle<SharedFunctionInfo> shared_info =
CreateTopLevelSharedFunctionInfo(parse_info, script, isolate);
if (FinalizeAllUnoptimizedCompilationJobs(
parse_info, isolate, shared_info, task->outer_function_job(),
task->inner_function_jobs(),
task->finalize_unoptimized_compilation_data())) {
maybe_result = shared_info;
}
}
if (maybe_result.is_null()) {
// Compilation failed - prepare to throw an exception after script
// fields have been set.
PreparePendingException(isolate, parse_info);
}
}
// Set the script fields after finalization, to keep this path the same
// between main-thread and off-thread finalization.
{
DisallowHeapAllocation no_gc;
SetScriptFieldsFromDetails(isolate, *script, script_details, &no_gc);
LOG(isolate, ScriptDetails(*script));
}
Handle<SharedFunctionInfo> result;
if (!maybe_result.ToHandle(&result)) {
FailWithPreparedPendingException(
isolate, script, task->compile_state()->pending_error_handler());
} else {
FinalizeUnoptimizedScriptCompilation(
isolate, script, task->flags(), task->compile_state(),
*task->finalize_unoptimized_compilation_data());
// Add compiled code to the isolate cache.
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.StreamingFinalization.AddToCache");
compilation_cache->PutScript(source, isolate->native_context(),
task->language_mode(), result);
}
}
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.StreamingFinalization.Release");
streaming_data->Release();
return maybe_result;
}
template <typename LocalIsolate>
Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
FunctionLiteral* literal, Handle<Script> script, LocalIsolate* isolate) {
// Precondition: code has been parsed and scopes have been analyzed.
MaybeHandle<SharedFunctionInfo> maybe_existing;
// Find any previously allocated shared function info for the given literal.
maybe_existing =
script->FindSharedFunctionInfo(isolate, literal->function_literal_id());
// If we found an existing shared function info, return it.
Handle<SharedFunctionInfo> existing;
if (maybe_existing.ToHandle(&existing)) {
// If the function has been uncompiled (bytecode flushed) it will have lost
// any preparsed data. If we produced preparsed data during this compile for
// this function, replace the uncompiled data with one that includes it.
if (literal->produced_preparse_data() != nullptr &&
existing->HasUncompiledDataWithoutPreparseData()) {
Handle<UncompiledData> existing_uncompiled_data =
handle(existing->uncompiled_data(), isolate);
DCHECK_EQ(literal->start_position(),
existing_uncompiled_data->start_position());
DCHECK_EQ(literal->end_position(),
existing_uncompiled_data->end_position());
// Use existing uncompiled data's inferred name as it may be more
// accurate than the literal we preparsed.
Handle<String> inferred_name =
handle(existing_uncompiled_data->inferred_name(), isolate);
Handle<PreparseData> preparse_data =
literal->produced_preparse_data()->Serialize(isolate);
Handle<UncompiledData> new_uncompiled_data =
isolate->factory()->NewUncompiledDataWithPreparseData(
inferred_name, existing_uncompiled_data->start_position(),
existing_uncompiled_data->end_position(), preparse_data);
existing->set_uncompiled_data(*new_uncompiled_data);
}
return existing;
}
// Allocate a shared function info object which will be compiled lazily.
Handle<SharedFunctionInfo> result =
isolate->factory()->NewSharedFunctionInfoForLiteral(literal, script,
false);
return result;
}
template Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
FunctionLiteral* literal, Handle<Script> script, Isolate* isolate);
template Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
FunctionLiteral* literal, Handle<Script> script, OffThreadIsolate* isolate);
MaybeHandle<Code> Compiler::GetOptimizedCodeForOSR(Handle<JSFunction> function,
BailoutId osr_offset,
JavaScriptFrame* osr_frame) {
DCHECK(!osr_offset.IsNone());
DCHECK_NOT_NULL(osr_frame);
return GetOptimizedCode(function, ConcurrencyMode::kNotConcurrent, osr_offset,
osr_frame);
}
bool Compiler::FinalizeOptimizedCompilationJob(OptimizedCompilationJob* job,
Isolate* isolate) {
VMState<COMPILER> state(isolate);
// Take ownership of compilation job. Deleting job also tears down the zone.
std::unique_ptr<OptimizedCompilationJob> job_scope(job);
OptimizedCompilationInfo* compilation_info = job->compilation_info();
TimerEventScope<TimerEventRecompileSynchronous> timer(isolate);
RuntimeCallTimerScope runtimeTimer(
isolate, RuntimeCallCounterId::kOptimizeConcurrentFinalize);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.OptimizeConcurrentFinalize");
Handle<SharedFunctionInfo> shared = compilation_info->shared_info();
// Reset profiler ticks, function is no longer considered hot.
compilation_info->closure()->feedback_vector().set_profiler_ticks(0);
DCHECK(!shared->HasBreakInfo());
// 1) Optimization on the concurrent thread may have failed.
// 2) The function may have already been optimized by OSR. Simply continue.
// Except when OSR already disabled optimization for some reason.
// 3) The code may have already been invalidated due to dependency change.
// 4) Code generation may have failed.
if (job->state() == CompilationJob::State::kReadyToFinalize) {
if (shared->optimization_disabled()) {
job->RetryOptimization(BailoutReason::kOptimizationDisabled);
} else if (job->FinalizeJob(isolate) == CompilationJob::SUCCEEDED) {
job->RecordCompilationStats(OptimizedCompilationJob::kConcurrent,
isolate);
job->RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG,
isolate);
InsertCodeIntoOptimizedCodeCache(compilation_info);
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[completed optimizing ");
compilation_info->closure()->ShortPrint(scope.file());
PrintF(scope.file(), "]\n");
}
compilation_info->closure()->set_code(*compilation_info->code());
return CompilationJob::SUCCEEDED;
}
}
DCHECK_EQ(job->state(), CompilationJob::State::kFailed);
if (FLAG_trace_opt) {
CodeTracer::Scope scope(isolate->GetCodeTracer());
PrintF(scope.file(), "[aborted optimizing ");
compilation_info->closure()->ShortPrint(scope.file());
PrintF(scope.file(), " because: %s]\n",
GetBailoutReason(compilation_info->bailout_reason()));
}
compilation_info->closure()->set_code(shared->GetCode());
// Clear the InOptimizationQueue marker, if it exists.
if (compilation_info->closure()->IsInOptimizationQueue()) {
compilation_info->closure()->ClearOptimizationMarker();
}
return CompilationJob::FAILED;
}
void Compiler::PostInstantiation(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
Handle<SharedFunctionInfo> shared(function->shared(), isolate);
IsCompiledScope is_compiled_scope(shared->is_compiled_scope());
// If code is compiled to bytecode (i.e., isn't asm.js), then allocate a
// feedback and check for optimized code.
if (is_compiled_scope.is_compiled() && shared->HasBytecodeArray()) {
JSFunction::InitializeFeedbackCell(function, &is_compiled_scope);
Code code = function->has_feedback_vector()
? function->feedback_vector().optimized_code()
: Code();
if (!code.is_null()) {
// Caching of optimized code enabled and optimized code found.
DCHECK(!code.marked_for_deoptimization());
DCHECK(function->shared().is_compiled());
function->set_code(code);
}
if (FLAG_always_opt && shared->allows_lazy_compilation() &&
!shared->optimization_disabled() && !function->IsOptimized() &&
!function->HasOptimizedCode()) {
JSFunction::EnsureFeedbackVector(function, &is_compiled_scope);
function->MarkForOptimization(ConcurrencyMode::kNotConcurrent);
}
}
if (shared->is_toplevel() || shared->is_wrapped()) {
// If it's a top-level script, report compilation to the debugger.
Handle<Script> script(Script::cast(shared->script()), isolate);
isolate->debug()->OnAfterCompile(script);
}
}
// ----------------------------------------------------------------------------
// Implementation of ScriptStreamingData
ScriptStreamingData::ScriptStreamingData(
std::unique_ptr<ScriptCompiler::ExternalSourceStream> source_stream,
ScriptCompiler::StreamedSource::Encoding encoding)
: source_stream(std::move(source_stream)), encoding(encoding) {}
ScriptStreamingData::~ScriptStreamingData() = default;
void ScriptStreamingData::Release() { task.reset(); }
} // namespace internal
} // namespace v8