// 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/compiler.h"
#include <algorithm>
#include <memory>
#include "src/asmjs/asm-js.h"
#include "src/asmjs/asm-typer.h"
#include "src/ast/ast-numbering.h"
#include "src/ast/prettyprinter.h"
#include "src/ast/scopes.h"
#include "src/bootstrapper.h"
#include "src/codegen.h"
#include "src/compilation-cache.h"
#include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
#include "src/compiler/pipeline.h"
#include "src/crankshaft/hydrogen.h"
#include "src/debug/debug.h"
#include "src/debug/liveedit.h"
#include "src/deoptimizer.h"
#include "src/frames-inl.h"
#include "src/full-codegen/full-codegen.h"
#include "src/globals.h"
#include "src/heap/heap.h"
#include "src/interpreter/interpreter.h"
#include "src/isolate-inl.h"
#include "src/log-inl.h"
#include "src/messages.h"
#include "src/parsing/parser.h"
#include "src/parsing/rewriter.h"
#include "src/parsing/scanner-character-streams.h"
#include "src/runtime-profiler.h"
#include "src/snapshot/code-serializer.h"
#include "src/vm-state-inl.h"
namespace v8 {
namespace internal {
// A wrapper around a CompilationInfo that detaches the Handles from
// the underlying DeferredHandleScope and stores them in info_ on
// destruction.
class CompilationHandleScope final {
public:
explicit CompilationHandleScope(CompilationInfo* info)
: deferred_(info->isolate()), info_(info) {}
~CompilationHandleScope() { info_->set_deferred_handles(deferred_.Detach()); }
private:
DeferredHandleScope deferred_;
CompilationInfo* info_;
};
// Helper that times a scoped region and records the elapsed time.
struct ScopedTimer {
explicit ScopedTimer(base::TimeDelta* location) : location_(location) {
DCHECK(location_ != NULL);
timer_.Start();
}
~ScopedTimer() { *location_ += timer_.Elapsed(); }
base::ElapsedTimer timer_;
base::TimeDelta* location_;
};
// ----------------------------------------------------------------------------
// Implementation of CompilationJob
CompilationJob::Status CompilationJob::PrepareJob() {
DCHECK(ThreadId::Current().Equals(info()->isolate()->thread_id()));
DisallowJavascriptExecution no_js(isolate());
if (FLAG_trace_opt && info()->IsOptimizing()) {
OFStream os(stdout);
os << "[compiling method " << Brief(*info()->closure()) << " using "
<< compiler_name_;
if (info()->is_osr()) os << " OSR";
os << "]" << std::endl;
}
// Delegate to the underlying implementation.
DCHECK(state() == State::kReadyToPrepare);
ScopedTimer t(&time_taken_to_prepare_);
return UpdateState(PrepareJobImpl(), State::kReadyToExecute);
}
CompilationJob::Status CompilationJob::ExecuteJob() {
std::unique_ptr<DisallowHeapAllocation> no_allocation;
std::unique_ptr<DisallowHandleAllocation> no_handles;
std::unique_ptr<DisallowHandleDereference> no_deref;
std::unique_ptr<DisallowCodeDependencyChange> no_dependency_change;
if (can_execute_on_background_thread()) {
no_allocation.reset(new DisallowHeapAllocation());
no_handles.reset(new DisallowHandleAllocation());
no_deref.reset(new DisallowHandleDereference());
no_dependency_change.reset(new DisallowCodeDependencyChange());
} else {
DCHECK(ThreadId::Current().Equals(info()->isolate()->thread_id()));
}
// Delegate to the underlying implementation.
DCHECK(state() == State::kReadyToExecute);
ScopedTimer t(&time_taken_to_execute_);
return UpdateState(ExecuteJobImpl(), State::kReadyToFinalize);
}
CompilationJob::Status CompilationJob::FinalizeJob() {
DCHECK(ThreadId::Current().Equals(info()->isolate()->thread_id()));
DisallowCodeDependencyChange no_dependency_change;
DisallowJavascriptExecution no_js(isolate());
DCHECK(!info()->dependencies()->HasAborted());
// Delegate to the underlying implementation.
DCHECK(state() == State::kReadyToFinalize);
ScopedTimer t(&time_taken_to_finalize_);
return UpdateState(FinalizeJobImpl(), State::kSucceeded);
}
CompilationJob::Status CompilationJob::RetryOptimization(BailoutReason reason) {
DCHECK(info_->IsOptimizing());
info_->RetryOptimization(reason);
state_ = State::kFailed;
return FAILED;
}
CompilationJob::Status CompilationJob::AbortOptimization(BailoutReason reason) {
DCHECK(info_->IsOptimizing());
info_->AbortOptimization(reason);
state_ = State::kFailed;
return FAILED;
}
void CompilationJob::RecordUnoptimizedCompilationStats() const {
int code_size;
if (info()->has_bytecode_array()) {
code_size = info()->bytecode_array()->SizeIncludingMetadata();
} else {
code_size = info()->code()->SizeIncludingMetadata();
}
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.
}
void CompilationJob::RecordOptimizedCompilationStats() const {
DCHECK(info()->IsOptimizing());
Handle<JSFunction> function = info()->closure();
if (!function->IsOptimized()) {
// Concurrent recompilation and OSR may race. Increment only once.
int opt_count = function->shared()->opt_count();
function->shared()->set_opt_count(opt_count + 1);
}
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) {
PrintF("[optimizing ");
function->ShortPrint();
PrintF(" - 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);
}
if (FLAG_hydrogen_stats) {
isolate()->GetHStatistics()->IncrementSubtotals(time_taken_to_prepare_,
time_taken_to_execute_,
time_taken_to_finalize_);
}
}
Isolate* CompilationJob::isolate() const { return info()->isolate(); }
namespace {
void AddWeakObjectToCodeDependency(Isolate* isolate, Handle<HeapObject> object,
Handle<Code> code) {
Handle<WeakCell> cell = Code::WeakCellFor(code);
Heap* heap = isolate->heap();
if (heap->InNewSpace(*object)) {
heap->AddWeakNewSpaceObjectToCodeDependency(object, cell);
} else {
Handle<DependentCode> dep(heap->LookupWeakObjectToCodeDependency(object));
dep =
DependentCode::InsertWeakCode(dep, DependentCode::kWeakCodeGroup, cell);
heap->AddWeakObjectToCodeDependency(object, dep);
}
}
} // namespace
void CompilationJob::RegisterWeakObjectsInOptimizedCode(Handle<Code> code) {
// TODO(turbofan): Move this to pipeline.cc once Crankshaft dies.
Isolate* const isolate = code->GetIsolate();
DCHECK(code->is_optimized_code());
std::vector<Handle<Map>> maps;
std::vector<Handle<HeapObject>> objects;
{
DisallowHeapAllocation no_gc;
int const mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::CELL);
for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
RelocInfo::Mode mode = it.rinfo()->rmode();
if (mode == RelocInfo::CELL &&
code->IsWeakObjectInOptimizedCode(it.rinfo()->target_cell())) {
objects.push_back(handle(it.rinfo()->target_cell(), isolate));
} else if (mode == RelocInfo::EMBEDDED_OBJECT &&
code->IsWeakObjectInOptimizedCode(
it.rinfo()->target_object())) {
Handle<HeapObject> object(HeapObject::cast(it.rinfo()->target_object()),
isolate);
if (object->IsMap()) {
maps.push_back(Handle<Map>::cast(object));
} else {
objects.push_back(object);
}
}
}
}
for (Handle<Map> map : maps) {
if (map->dependent_code()->IsEmpty(DependentCode::kWeakCodeGroup)) {
isolate->heap()->AddRetainedMap(map);
}
Map::AddDependentCode(map, DependentCode::kWeakCodeGroup, code);
}
for (Handle<HeapObject> object : objects) {
AddWeakObjectToCodeDependency(isolate, object, code);
}
code->set_can_have_weak_objects(true);
}
// ----------------------------------------------------------------------------
// Local helper methods that make up the compilation pipeline.
namespace {
bool IsEvalToplevel(Handle<SharedFunctionInfo> shared) {
return shared->is_toplevel() && shared->script()->IsScript() &&
Script::cast(shared->script())->compilation_type() ==
Script::COMPILATION_TYPE_EVAL;
}
bool Parse(ParseInfo* info) {
// Create a canonical handle scope if compiling ignition bytecode. This is
// required by the constant array builder to de-duplicate objects without
// dereferencing handles.
std::unique_ptr<CanonicalHandleScope> canonical;
if (FLAG_ignition) canonical.reset(new CanonicalHandleScope(info->isolate()));
return Parser::ParseStatic(info);
}
void RecordFunctionCompilation(CodeEventListener::LogEventsAndTags tag,
CompilationInfo* info) {
// 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 (info->isolate()->logger()->is_logging_code_events() ||
info->isolate()->is_profiling()) {
Handle<SharedFunctionInfo> shared = info->shared_info();
Handle<Script> script = info->parse_info()->script();
Handle<AbstractCode> abstract_code =
info->has_bytecode_array()
? Handle<AbstractCode>::cast(info->bytecode_array())
: Handle<AbstractCode>::cast(info->code());
if (abstract_code.is_identical_to(
info->isolate()->builtins()->CompileLazy())) {
return;
}
int line_num = Script::GetLineNumber(script, shared->start_position()) + 1;
int column_num =
Script::GetColumnNumber(script, shared->start_position()) + 1;
String* script_name = script->name()->IsString()
? String::cast(script->name())
: info->isolate()->heap()->empty_string();
CodeEventListener::LogEventsAndTags log_tag =
Logger::ToNativeByScript(tag, *script);
PROFILE(info->isolate(),
CodeCreateEvent(log_tag, *abstract_code, *shared, script_name,
line_num, column_num));
}
}
void EnsureFeedbackMetadata(CompilationInfo* info) {
DCHECK(info->has_shared_info());
// If no type feedback metadata exists, we create it now. At this point the
// AstNumbering pass has already run. Note the snapshot can contain outdated
// vectors for a different configuration, hence we also recreate a new vector
// when the function is not compiled (i.e. no code was serialized).
// TODO(mvstanton): reintroduce is_empty() predicate to feedback_metadata().
if (info->shared_info()->feedback_metadata()->length() == 0 ||
!info->shared_info()->is_compiled()) {
Handle<TypeFeedbackMetadata> feedback_metadata = TypeFeedbackMetadata::New(
info->isolate(), info->literal()->feedback_vector_spec());
info->shared_info()->set_feedback_metadata(*feedback_metadata);
}
// It's very important that recompiles do not alter the structure of the type
// feedback vector. Verify that the structure fits the function literal.
CHECK(!info->shared_info()->feedback_metadata()->SpecDiffersFrom(
info->literal()->feedback_vector_spec()));
}
bool ShouldUseIgnition(CompilationInfo* info) {
if (!FLAG_ignition) return false;
DCHECK(info->has_shared_info());
// When requesting debug code as a replacement for existing code, we provide
// the same kind as the existing code (to prevent implicit tier-change).
if (info->is_debug() && info->shared_info()->is_compiled()) {
return !info->shared_info()->HasBaselineCode();
}
// Since we can't OSR from Ignition, skip Ignition for asm.js functions.
if (info->shared_info()->asm_function()) {
return false;
}
// Checks whether top level functions should be passed by the filter.
if (info->shared_info()->is_toplevel()) {
Vector<const char> filter = CStrVector(FLAG_ignition_filter);
return (filter.length() == 0) || (filter.length() == 1 && filter[0] == '*');
}
// Finally respect the filter.
return info->shared_info()->PassesFilter(FLAG_ignition_filter);
}
CompilationJob* GetUnoptimizedCompilationJob(CompilationInfo* info) {
// Function should have been parsed and analyzed before creating a compilation
// job.
DCHECK_NOT_NULL(info->literal());
DCHECK_NOT_NULL(info->scope());
EnsureFeedbackMetadata(info);
if (ShouldUseIgnition(info)) {
return interpreter::Interpreter::NewCompilationJob(info);
} else {
return FullCodeGenerator::NewCompilationJob(info);
}
}
void InstallSharedScopeInfo(CompilationInfo* info,
Handle<SharedFunctionInfo> shared) {
Handle<ScopeInfo> scope_info = info->scope()->scope_info();
shared->set_scope_info(*scope_info);
Scope* outer_scope = info->scope()->GetOuterScopeWithContext();
if (outer_scope) {
shared->set_outer_scope_info(*outer_scope->scope_info());
}
}
void InstallSharedCompilationResult(CompilationInfo* info,
Handle<SharedFunctionInfo> shared) {
// TODO(mstarzinger): Compiling for debug code might be used to reveal inner
// functions via {FindSharedFunctionInfoInScript}, in which case we end up
// regenerating existing bytecode. Fix this!
if (info->is_debug() && info->has_bytecode_array()) {
shared->ClearBytecodeArray();
}
DCHECK(!info->code().is_null());
shared->ReplaceCode(*info->code());
if (info->has_bytecode_array()) {
DCHECK(!shared->HasBytecodeArray()); // Only compiled once.
shared->set_bytecode_array(*info->bytecode_array());
}
}
void InstallUnoptimizedCode(CompilationInfo* info) {
Handle<SharedFunctionInfo> shared = info->shared_info();
// Update the shared function info with the scope info.
InstallSharedScopeInfo(info, shared);
// Install compilation result on the shared function info
InstallSharedCompilationResult(info, shared);
}
CompilationJob::Status FinalizeUnoptimizedCompilationJob(CompilationJob* job) {
CompilationJob::Status status = job->FinalizeJob();
if (status == CompilationJob::SUCCEEDED) {
InstallUnoptimizedCode(job->info());
job->RecordUnoptimizedCompilationStats();
}
return status;
}
bool GenerateUnoptimizedCode(CompilationInfo* info) {
if (FLAG_validate_asm && info->scope()->asm_module() &&
!info->shared_info()->is_asm_wasm_broken()) {
EnsureFeedbackMetadata(info);
MaybeHandle<FixedArray> wasm_data;
wasm_data = AsmJs::ConvertAsmToWasm(info->parse_info());
if (!wasm_data.is_null()) {
info->shared_info()->set_asm_wasm_data(*wasm_data.ToHandleChecked());
info->SetCode(info->isolate()->builtins()->InstantiateAsmJs());
InstallUnoptimizedCode(info);
return true;
}
}
std::unique_ptr<CompilationJob> job(GetUnoptimizedCompilationJob(info));
if (job->PrepareJob() != CompilationJob::SUCCEEDED) return false;
if (job->ExecuteJob() != CompilationJob::SUCCEEDED) return false;
if (FinalizeUnoptimizedCompilationJob(job.get()) !=
CompilationJob::SUCCEEDED) {
return false;
}
return true;
}
bool CompileUnoptimizedCode(CompilationInfo* info) {
DCHECK(AllowCompilation::IsAllowed(info->isolate()));
if (!Compiler::Analyze(info->parse_info()) ||
!GenerateUnoptimizedCode(info)) {
Isolate* isolate = info->isolate();
if (!isolate->has_pending_exception()) isolate->StackOverflow();
return false;
}
return true;
}
MUST_USE_RESULT MaybeHandle<Code> GetUnoptimizedCode(CompilationInfo* info) {
VMState<COMPILER> state(info->isolate());
PostponeInterruptsScope postpone(info->isolate());
// Parse and update CompilationInfo with the results.
if (!Parse(info->parse_info())) return MaybeHandle<Code>();
DCHECK_EQ(info->shared_info()->language_mode(),
info->literal()->language_mode());
// Compile either unoptimized code or bytecode for the interpreter.
if (!CompileUnoptimizedCode(info)) return MaybeHandle<Code>();
// Record the function compilation event.
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG, info);
return info->code();
}
MUST_USE_RESULT MaybeHandle<Code> GetCodeFromOptimizedCodeMap(
Handle<JSFunction> function, BailoutId osr_ast_id) {
Handle<SharedFunctionInfo> shared(function->shared());
DisallowHeapAllocation no_gc;
CodeAndLiterals cached = shared->SearchOptimizedCodeMap(
function->context()->native_context(), osr_ast_id);
if (cached.code != nullptr) {
// Caching of optimized code enabled and optimized code found.
if (cached.literals != nullptr) function->set_literals(cached.literals);
DCHECK(!cached.code->marked_for_deoptimization());
DCHECK(function->shared()->is_compiled());
return Handle<Code>(cached.code);
}
return MaybeHandle<Code>();
}
void InsertCodeIntoOptimizedCodeMap(CompilationInfo* info) {
Handle<Code> code = 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 (info->is_function_context_specializing()) return;
// Frame specialization implies function context specialization.
DCHECK(!info->is_frame_specializing());
// TODO(4764): When compiling for OSR from bytecode, BailoutId might derive
// from bytecode offset and overlap with actual BailoutId. No caching!
if (info->is_osr() && info->is_optimizing_from_bytecode()) return;
// Cache optimized context-specific code.
Handle<JSFunction> function = info->closure();
Handle<SharedFunctionInfo> shared(function->shared());
Handle<LiteralsArray> literals(function->literals());
Handle<Context> native_context(function->context()->native_context());
SharedFunctionInfo::AddToOptimizedCodeMap(shared, native_context, code,
literals, info->osr_ast_id());
}
bool Renumber(ParseInfo* parse_info) {
// Create a canonical handle scope if compiling ignition bytecode. This is
// required by the constant array builder to de-duplicate objects without
// dereferencing handles.
std::unique_ptr<CanonicalHandleScope> canonical;
if (FLAG_ignition) {
canonical.reset(new CanonicalHandleScope(parse_info->isolate()));
}
if (!AstNumbering::Renumber(parse_info->isolate(), parse_info->zone(),
parse_info->literal())) {
return false;
}
Handle<SharedFunctionInfo> shared_info = parse_info->shared_info();
if (!shared_info.is_null()) {
FunctionLiteral* lit = parse_info->literal();
shared_info->set_ast_node_count(lit->ast_node_count());
if (lit->dont_optimize_reason() != kNoReason) {
shared_info->DisableOptimization(lit->dont_optimize_reason());
}
if (lit->flags() & AstProperties::kDontCrankshaft) {
shared_info->set_dont_crankshaft(true);
}
}
return true;
}
bool UseTurboFan(Handle<SharedFunctionInfo> shared) {
bool optimization_disabled = shared->optimization_disabled();
bool dont_crankshaft = shared->dont_crankshaft();
// Check the enabling conditions for Turbofan.
// 1. "use asm" code.
bool is_turbofanable_asm =
FLAG_turbo_asm && shared->asm_function() && !optimization_disabled;
// 2. Fallback for features unsupported by Crankshaft.
bool is_unsupported_by_crankshaft_but_turbofanable =
dont_crankshaft && strcmp(FLAG_turbo_filter, "~~") == 0 &&
!optimization_disabled;
// 3. Explicitly enabled by the command-line filter.
bool passes_turbo_filter = shared->PassesFilter(FLAG_turbo_filter);
return is_turbofanable_asm || is_unsupported_by_crankshaft_but_turbofanable ||
passes_turbo_filter;
}
bool GetOptimizedCodeNow(CompilationJob* job) {
CompilationInfo* info = job->info();
Isolate* isolate = info->isolate();
// Parsing is not required when optimizing from existing bytecode.
if (!info->is_optimizing_from_bytecode()) {
if (!Compiler::ParseAndAnalyze(info->parse_info())) return false;
EnsureFeedbackMetadata(info);
}
JSFunction::EnsureLiterals(info->closure());
TimerEventScope<TimerEventRecompileSynchronous> timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate,
&RuntimeCallStats::RecompileSynchronous);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.RecompileSynchronous");
if (job->PrepareJob() != CompilationJob::SUCCEEDED ||
job->ExecuteJob() != CompilationJob::SUCCEEDED ||
job->FinalizeJob() != CompilationJob::SUCCEEDED) {
if (FLAG_trace_opt) {
PrintF("[aborted optimizing ");
info->closure()->ShortPrint();
PrintF(" because: %s]\n", GetBailoutReason(info->bailout_reason()));
}
return false;
}
// Success!
job->RecordOptimizedCompilationStats();
DCHECK(!isolate->has_pending_exception());
InsertCodeIntoOptimizedCodeMap(info);
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG, info);
return true;
}
bool GetOptimizedCodeLater(CompilationJob* job) {
CompilationInfo* info = job->info();
Isolate* isolate = info->isolate();
if (!isolate->optimizing_compile_dispatcher()->IsQueueAvailable()) {
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Compilation queue full, will retry optimizing ");
info->closure()->ShortPrint();
PrintF(" later.\n");
}
return false;
}
if (isolate->heap()->HighMemoryPressure()) {
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** High memory pressure, will retry optimizing ");
info->closure()->ShortPrint();
PrintF(" later.\n");
}
return false;
}
// Parsing is not required when optimizing from existing bytecode.
if (!info->is_optimizing_from_bytecode()) {
if (!Compiler::ParseAndAnalyze(info->parse_info())) return false;
EnsureFeedbackMetadata(info);
}
JSFunction::EnsureLiterals(info->closure());
TimerEventScope<TimerEventRecompileSynchronous> timer(info->isolate());
RuntimeCallTimerScope runtimeTimer(info->isolate(),
&RuntimeCallStats::RecompileSynchronous);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.RecompileSynchronous");
if (job->PrepareJob() != CompilationJob::SUCCEEDED) return false;
isolate->optimizing_compile_dispatcher()->QueueForOptimization(job);
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Queued ");
info->closure()->ShortPrint();
PrintF(" for concurrent optimization.\n");
}
return true;
}
MaybeHandle<Code> GetOptimizedCode(Handle<JSFunction> function,
Compiler::ConcurrencyMode mode,
BailoutId osr_ast_id = BailoutId::None(),
JavaScriptFrame* osr_frame = nullptr) {
Isolate* isolate = function->GetIsolate();
Handle<SharedFunctionInfo> shared(function->shared(), isolate);
bool ignition_osr = osr_frame && osr_frame->is_interpreted();
DCHECK_IMPLIES(ignition_osr, !osr_ast_id.IsNone());
DCHECK_IMPLIES(ignition_osr, FLAG_ignition_osr);
// Flag combination --ignition-osr --no-turbo-from-bytecode is unsupported.
if (ignition_osr && !FLAG_turbo_from_bytecode) return MaybeHandle<Code>();
Handle<Code> cached_code;
// TODO(4764): When compiling for OSR from bytecode, BailoutId might derive
// from bytecode offset and overlap with actual BailoutId. No lookup!
if (!ignition_osr &&
GetCodeFromOptimizedCodeMap(function, osr_ast_id)
.ToHandle(&cached_code)) {
if (FLAG_trace_opt) {
PrintF("[found optimized code for ");
function->ShortPrint();
if (!osr_ast_id.IsNone()) {
PrintF(" at OSR AST id %d", osr_ast_id.ToInt());
}
PrintF("]\n");
}
return cached_code;
}
// Reset profiler ticks, function is no longer considered hot.
if (shared->is_compiled()) {
shared->code()->set_profiler_ticks(0);
}
VMState<COMPILER> state(isolate);
DCHECK(!isolate->has_pending_exception());
PostponeInterruptsScope postpone(isolate);
bool use_turbofan = UseTurboFan(shared) || ignition_osr;
std::unique_ptr<CompilationJob> job(
use_turbofan ? compiler::Pipeline::NewCompilationJob(function)
: new HCompilationJob(function));
CompilationInfo* info = job->info();
ParseInfo* parse_info = info->parse_info();
info->SetOptimizingForOsr(osr_ast_id, osr_frame);
// Do not use Crankshaft/TurboFan if we need to be able to set break points.
if (info->shared_info()->HasDebugInfo()) {
info->AbortOptimization(kFunctionBeingDebugged);
return MaybeHandle<Code>();
}
// Limit the number of times we try to optimize functions.
const int kMaxOptCount =
FLAG_deopt_every_n_times == 0 ? FLAG_max_opt_count : 1000;
if (info->shared_info()->opt_count() > kMaxOptCount) {
info->AbortOptimization(kOptimizedTooManyTimes);
return MaybeHandle<Code>();
}
TimerEventScope<TimerEventOptimizeCode> optimize_code_timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate, &RuntimeCallStats::OptimizeCode);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.OptimizeCode");
// TurboFan can optimize directly from existing bytecode.
if (FLAG_turbo_from_bytecode && use_turbofan && ShouldUseIgnition(info)) {
if (info->is_osr() && !ignition_osr) return MaybeHandle<Code>();
if (!Compiler::EnsureBytecode(info)) {
if (isolate->has_pending_exception()) isolate->clear_pending_exception();
return MaybeHandle<Code>();
}
info->MarkAsOptimizeFromBytecode();
}
if (IsEvalToplevel(shared)) {
parse_info->set_eval();
parse_info->set_toplevel();
parse_info->set_allow_lazy_parsing(false);
}
// Verify that OSR compilations are delegated to the correct graph builder.
// Depending on the underlying frame the semantics of the {BailoutId} differ
// and the various graph builders hard-code a certain semantic:
// - Interpreter : The BailoutId represents a bytecode offset.
// - FullCodegen : The BailoutId represents the id of an AST node.
DCHECK_IMPLIES(info->is_osr() && ignition_osr,
info->is_optimizing_from_bytecode());
DCHECK_IMPLIES(info->is_osr() && !ignition_osr,
!info->is_optimizing_from_bytecode());
// 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.
std::unique_ptr<CompilationHandleScope> compilation;
if (mode == Compiler::CONCURRENT) {
compilation.reset(new CompilationHandleScope(info));
}
// In case of TurboFan, all handles below will be canonicalized.
std::unique_ptr<CanonicalHandleScope> canonical;
if (use_turbofan) canonical.reset(new CanonicalHandleScope(info->isolate()));
// Reopen handles in the new CompilationHandleScope.
info->ReopenHandlesInNewHandleScope();
parse_info->ReopenHandlesInNewHandleScope();
if (mode == Compiler::CONCURRENT) {
if (GetOptimizedCodeLater(job.get())) {
job.release(); // The background recompile job owns this now.
return isolate->builtins()->InOptimizationQueue();
}
} else {
if (GetOptimizedCodeNow(job.get())) return info->code();
}
if (isolate->has_pending_exception()) isolate->clear_pending_exception();
return MaybeHandle<Code>();
}
CompilationJob::Status FinalizeOptimizedCompilationJob(CompilationJob* job) {
CompilationInfo* info = job->info();
Isolate* isolate = info->isolate();
TimerEventScope<TimerEventRecompileSynchronous> timer(info->isolate());
RuntimeCallTimerScope runtimeTimer(isolate,
&RuntimeCallStats::RecompileSynchronous);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.RecompileSynchronous");
Handle<SharedFunctionInfo> shared = info->shared_info();
shared->code()->set_profiler_ticks(0);
DCHECK(!shared->HasDebugInfo());
// 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(kOptimizationDisabled);
} else if (info->dependencies()->HasAborted()) {
job->RetryOptimization(kBailedOutDueToDependencyChange);
} else if (job->FinalizeJob() == CompilationJob::SUCCEEDED) {
job->RecordOptimizedCompilationStats();
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG, info);
if (shared
->SearchOptimizedCodeMap(info->context()->native_context(),
info->osr_ast_id())
.code == nullptr) {
InsertCodeIntoOptimizedCodeMap(info);
}
if (FLAG_trace_opt) {
PrintF("[completed optimizing ");
info->closure()->ShortPrint();
PrintF("]\n");
}
info->closure()->ReplaceCode(*info->code());
return CompilationJob::SUCCEEDED;
}
}
DCHECK(job->state() == CompilationJob::State::kFailed);
if (FLAG_trace_opt) {
PrintF("[aborted optimizing ");
info->closure()->ShortPrint();
PrintF(" because: %s]\n", GetBailoutReason(info->bailout_reason()));
}
info->closure()->ReplaceCode(shared->code());
return CompilationJob::FAILED;
}
class InterpreterActivationsFinder : public ThreadVisitor,
public OptimizedFunctionVisitor {
public:
explicit InterpreterActivationsFinder(SharedFunctionInfo* shared)
: shared_(shared), has_activations_(false) {}
void VisitThread(Isolate* isolate, ThreadLocalTop* top) {
Address* activation_pc_address = nullptr;
JavaScriptFrameIterator it(isolate, top);
for (; !it.done(); it.Advance()) {
JavaScriptFrame* frame = it.frame();
if (FLAG_turbo_from_bytecode && FLAG_ignition_osr &&
frame->is_optimized() && frame->function()->shared() == shared_) {
// If we are able to optimize functions directly from bytecode, then
// there might be optimized OSR code active on the stack that is not
// reachable through a function. We count this as an activation.
has_activations_ = true;
}
if (frame->is_interpreted() && frame->function()->shared() == shared_) {
has_activations_ = true;
activation_pc_address = frame->pc_address();
}
}
if (activation_pc_address) {
activation_pc_addresses_.push_back(activation_pc_address);
}
}
void VisitFunction(JSFunction* function) {
if (function->Inlines(shared_)) has_activations_ = true;
}
void EnterContext(Context* context) {}
void LeaveContext(Context* context) {}
bool MarkActivationsForBaselineOnReturn(Isolate* isolate) {
if (activation_pc_addresses_.empty()) return false;
for (Address* activation_pc_address : activation_pc_addresses_) {
DCHECK(isolate->inner_pointer_to_code_cache()
->GetCacheEntry(*activation_pc_address)
->code->is_interpreter_trampoline_builtin());
*activation_pc_address =
isolate->builtins()->InterpreterMarkBaselineOnReturn()->entry();
}
return true;
}
bool has_activations() { return has_activations_; }
private:
SharedFunctionInfo* shared_;
bool has_activations_;
std::vector<Address*> activation_pc_addresses_;
};
bool HasInterpreterActivations(
Isolate* isolate, InterpreterActivationsFinder* activations_finder) {
activations_finder->VisitThread(isolate, isolate->thread_local_top());
isolate->thread_manager()->IterateArchivedThreads(activations_finder);
if (FLAG_turbo_from_bytecode) {
// If we are able to optimize functions directly from bytecode, then there
// might be optimized functions that rely on bytecode being around. We need
// to prevent switching the given function to baseline code in those cases.
Deoptimizer::VisitAllOptimizedFunctions(isolate, activations_finder);
}
return activations_finder->has_activations();
}
MaybeHandle<Code> GetBaselineCode(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
VMState<COMPILER> state(isolate);
PostponeInterruptsScope postpone(isolate);
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, function);
CompilationInfo info(&parse_info, function);
// Reset profiler ticks, function is no longer considered hot.
if (function->shared()->HasBytecodeArray()) {
function->shared()->set_profiler_ticks(0);
}
// Nothing left to do if the function already has baseline code.
if (function->shared()->code()->kind() == Code::FUNCTION) {
return Handle<Code>(function->shared()->code());
}
// We do not switch to baseline code when the debugger might have created a
// copy of the bytecode with break slots to be able to set break points.
if (function->shared()->HasDebugInfo()) {
return MaybeHandle<Code>();
}
// TODO(4280): For now we do not switch generators or async functions to
// baseline code because there might be suspended activations stored in
// generator objects on the heap. We could eventually go directly to
// TurboFan in this case.
if (IsResumableFunction(function->shared()->kind())) {
return MaybeHandle<Code>();
}
// TODO(4280): For now we disable switching to baseline code in the presence
// of interpreter activations of the given function. The reasons is that the
// underlying bytecode is cleared below. Note that this only applies in case
// the --ignition-preserve-bytecode flag is not passed.
if (!FLAG_ignition_preserve_bytecode) {
InterpreterActivationsFinder activations_finder(function->shared());
if (HasInterpreterActivations(isolate, &activations_finder)) {
if (FLAG_trace_opt) {
OFStream os(stdout);
os << "[unable to switch " << Brief(*function) << " due to activations]"
<< std::endl;
}
if (activations_finder.MarkActivationsForBaselineOnReturn(isolate)) {
if (FLAG_trace_opt) {
OFStream os(stdout);
os << "[marking " << Brief(function->shared())
<< " for baseline recompilation on return]" << std::endl;
}
}
return MaybeHandle<Code>();
}
}
if (FLAG_trace_opt) {
OFStream os(stdout);
os << "[switching method " << Brief(*function) << " to baseline code]"
<< std::endl;
}
// Parse and update CompilationInfo with the results.
if (!Parse(info.parse_info())) return MaybeHandle<Code>();
Handle<SharedFunctionInfo> shared = info.shared_info();
DCHECK_EQ(shared->language_mode(), info.literal()->language_mode());
// Compile baseline code using the full code generator.
if (!Compiler::Analyze(info.parse_info()) ||
!FullCodeGenerator::MakeCode(&info)) {
if (!isolate->has_pending_exception()) isolate->StackOverflow();
return MaybeHandle<Code>();
}
// TODO(4280): For now we play it safe and remove the bytecode array when we
// switch to baseline code. We might consider keeping around the bytecode so
// that it can be used as the "source of truth" eventually. Note that this
// only applies in case the --ignition-preserve-bytecode flag is not passed.
if (!FLAG_ignition_preserve_bytecode) shared->ClearBytecodeArray();
// Update the shared function info with the scope info.
InstallSharedScopeInfo(&info, shared);
// Install compilation result on the shared function info
InstallSharedCompilationResult(&info, shared);
// Record the function compilation event.
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG, &info);
return info.code();
}
MaybeHandle<Code> GetLazyCode(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
DCHECK(!isolate->has_pending_exception());
DCHECK(!function->is_compiled());
TimerEventScope<TimerEventCompileCode> compile_timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate,
&RuntimeCallStats::CompileCodeLazy);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileCode");
AggregatedHistogramTimerScope timer(isolate->counters()->compile_lazy());
Handle<Code> cached_code;
if (GetCodeFromOptimizedCodeMap(function, BailoutId::None())
.ToHandle(&cached_code)) {
if (FLAG_trace_opt) {
PrintF("[found optimized code for ");
function->ShortPrint();
PrintF(" during unoptimized compile]\n");
}
DCHECK(function->shared()->is_compiled());
return cached_code;
}
if (function->shared()->is_compiled()) {
return Handle<Code>(function->shared()->code());
}
if (function->shared()->HasBytecodeArray()) {
Handle<Code> entry = isolate->builtins()->InterpreterEntryTrampoline();
function->shared()->ReplaceCode(*entry);
return entry;
}
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, function);
CompilationInfo info(&parse_info, function);
Handle<Code> result;
ASSIGN_RETURN_ON_EXCEPTION(isolate, result, GetUnoptimizedCode(&info), Code);
if (FLAG_always_opt) {
Handle<Code> opt_code;
if (GetOptimizedCode(function, Compiler::NOT_CONCURRENT)
.ToHandle(&opt_code)) {
result = opt_code;
}
}
return result;
}
Handle<SharedFunctionInfo> NewSharedFunctionInfoForLiteral(
Isolate* isolate, FunctionLiteral* literal, Handle<Script> script) {
Handle<Code> code = isolate->builtins()->CompileLazy();
Handle<ScopeInfo> scope_info = handle(ScopeInfo::Empty(isolate));
Handle<SharedFunctionInfo> result = isolate->factory()->NewSharedFunctionInfo(
literal->name(), literal->materialized_literal_count(), literal->kind(),
code, scope_info);
SharedFunctionInfo::InitFromFunctionLiteral(result, literal);
SharedFunctionInfo::SetScript(result, script);
return result;
}
Handle<SharedFunctionInfo> CompileToplevel(CompilationInfo* info) {
Isolate* isolate = info->isolate();
TimerEventScope<TimerEventCompileCode> timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate, &RuntimeCallStats::CompileCode);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileCode");
PostponeInterruptsScope postpone(isolate);
DCHECK(!isolate->native_context().is_null());
ParseInfo* parse_info = info->parse_info();
Handle<Script> script = parse_info->script();
// TODO(svenpanne) Obscure place for this, perhaps move to OnBeforeCompile?
FixedArray* array = isolate->native_context()->embedder_data();
script->set_context_data(array->get(v8::Context::kDebugIdIndex));
isolate->debug()->OnBeforeCompile(script);
parse_info->set_toplevel();
Handle<SharedFunctionInfo> result;
{ VMState<COMPILER> state(info->isolate());
if (parse_info->literal() == NULL) {
// Parse the script if needed (if it's already parsed, literal() is
// non-NULL). If compiling for debugging, we may eagerly compile inner
// functions, so do not parse lazily in that case.
ScriptCompiler::CompileOptions options = parse_info->compile_options();
bool parse_allow_lazy =
options == ScriptCompiler::kConsumeParserCache ||
String::cast(script->source())->length() > FLAG_min_preparse_length;
parse_info->set_allow_lazy_parsing(parse_allow_lazy);
if (!parse_allow_lazy &&
(options == ScriptCompiler::kProduceParserCache ||
options == ScriptCompiler::kConsumeParserCache)) {
// We are going to parse eagerly, but we either 1) have cached data
// produced by lazy parsing or 2) are asked to generate cached data.
// Eager parsing cannot benefit from cached data, and producing cached
// data while parsing eagerly is not implemented.
parse_info->set_cached_data(nullptr);
parse_info->set_compile_options(ScriptCompiler::kNoCompileOptions);
}
if (!Parse(parse_info)) {
return Handle<SharedFunctionInfo>::null();
}
}
FunctionLiteral* lit = parse_info->literal();
// 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.
RuntimeCallTimerScope runtimeTimer(
isolate, parse_info->is_eval() ? &RuntimeCallStats::CompileEval
: &RuntimeCallStats::Compile);
HistogramTimer* rate = parse_info->is_eval()
? info->isolate()->counters()->compile_eval()
: info->isolate()->counters()->compile();
HistogramTimerScope timer(rate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
parse_info->is_eval() ? "V8.CompileEval" : "V8.Compile");
// Allocate a shared function info object.
DCHECK_EQ(kNoSourcePosition, lit->function_token_position());
result = NewSharedFunctionInfoForLiteral(isolate, lit, script);
result->set_is_toplevel(true);
parse_info->set_shared_info(result);
// Compile the code.
if (!CompileUnoptimizedCode(info)) {
return Handle<SharedFunctionInfo>::null();
}
Handle<String> script_name =
script->name()->IsString()
? Handle<String>(String::cast(script->name()))
: isolate->factory()->empty_string();
CodeEventListener::LogEventsAndTags log_tag =
parse_info->is_eval()
? CodeEventListener::EVAL_TAG
: Logger::ToNativeByScript(CodeEventListener::SCRIPT_TAG, *script);
PROFILE(isolate, CodeCreateEvent(log_tag, result->abstract_code(), *result,
*script_name));
if (!script.is_null())
script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
}
return result;
}
} // namespace
// ----------------------------------------------------------------------------
// Implementation of Compiler
bool Compiler::Analyze(ParseInfo* info) {
DCHECK_NOT_NULL(info->literal());
if (!Rewriter::Rewrite(info)) return false;
DeclarationScope::Analyze(info, AnalyzeMode::kRegular);
if (!Renumber(info)) return false;
DCHECK_NOT_NULL(info->scope());
return true;
}
bool Compiler::ParseAndAnalyze(ParseInfo* info) {
if (!Parse(info)) return false;
if (!Compiler::Analyze(info)) return false;
DCHECK_NOT_NULL(info->literal());
DCHECK_NOT_NULL(info->scope());
return true;
}
bool Compiler::Compile(Handle<JSFunction> function, ClearExceptionFlag flag) {
if (function->is_compiled()) return true;
Isolate* isolate = function->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// Start a compilation.
Handle<Code> code;
if (!GetLazyCode(function).ToHandle(&code)) {
if (flag == CLEAR_EXCEPTION) {
isolate->clear_pending_exception();
}
return false;
}
// Install code on closure.
function->ReplaceCode(*code);
JSFunction::EnsureLiterals(function);
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared()->is_compiled());
DCHECK(function->is_compiled());
return true;
}
bool Compiler::CompileBaseline(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// Start a compilation.
Handle<Code> code;
if (!GetBaselineCode(function).ToHandle(&code)) {
// Baseline generation failed, get unoptimized code.
DCHECK(function->shared()->is_compiled());
code = handle(function->shared()->code());
isolate->clear_pending_exception();
}
// Install code on closure.
function->ReplaceCode(*code);
JSFunction::EnsureLiterals(function);
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared()->is_compiled());
DCHECK(function->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.
DCHECK(!isolate->has_pending_exception());
if (function->shared()->is_compiled()) {
code = handle(function->shared()->code(), isolate);
} else if (function->shared()->HasBytecodeArray()) {
code = isolate->builtins()->InterpreterEntryTrampoline();
function->shared()->ReplaceCode(*code);
} else {
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, function);
CompilationInfo info(&parse_info, function);
if (!GetUnoptimizedCode(&info).ToHandle(&code)) {
return false;
}
}
}
// Install code on closure.
function->ReplaceCode(*code);
JSFunction::EnsureLiterals(function);
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared()->is_compiled());
DCHECK(function->is_compiled());
return true;
}
bool Compiler::CompileDebugCode(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// Start a compilation.
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, function);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
if (IsEvalToplevel(handle(function->shared()))) {
parse_info.set_eval();
parse_info.set_toplevel();
parse_info.set_allow_lazy_parsing(false);
}
info.MarkAsDebug();
if (GetUnoptimizedCode(&info).is_null()) {
isolate->clear_pending_exception();
return false;
}
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(function->shared()->is_compiled());
DCHECK(function->shared()->HasDebugCode());
return true;
}
bool Compiler::CompileDebugCode(Handle<SharedFunctionInfo> shared) {
Isolate* isolate = shared->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// Start a compilation.
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, shared);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
if (IsEvalToplevel(shared)) {
parse_info.set_eval();
parse_info.set_toplevel();
parse_info.set_allow_lazy_parsing(false);
}
info.MarkAsDebug();
if (GetUnoptimizedCode(&info).is_null()) {
isolate->clear_pending_exception();
return false;
}
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
DCHECK(shared->is_compiled());
DCHECK(shared->HasDebugCode());
return true;
}
MaybeHandle<JSArray> Compiler::CompileForLiveEdit(Handle<Script> script) {
Isolate* isolate = script->GetIsolate();
DCHECK(AllowCompilation::IsAllowed(isolate));
// In order to ensure that live edit function info collection finds the newly
// generated shared function infos, clear the script's list temporarily
// and restore it at the end of this method.
Handle<Object> old_function_infos(script->shared_function_infos(), isolate);
script->set_shared_function_infos(Smi::kZero);
// Start a compilation.
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, script);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
info.MarkAsDebug();
// TODO(635): support extensions.
const bool compilation_succeeded = !CompileToplevel(&info).is_null();
Handle<JSArray> infos;
if (compilation_succeeded) {
// Check postconditions on success.
DCHECK(!isolate->has_pending_exception());
infos = LiveEditFunctionTracker::Collect(parse_info.literal(), script,
&zone, isolate);
}
// Restore the original function info list in order to remain side-effect
// free as much as possible, since some code expects the old shared function
// infos to stick around.
script->set_shared_function_infos(*old_function_infos);
return infos;
}
bool Compiler::EnsureBytecode(CompilationInfo* info) {
if (!ShouldUseIgnition(info)) return false;
if (!info->shared_info()->HasBytecodeArray()) {
Handle<Code> original_code(info->shared_info()->code());
if (GetUnoptimizedCode(info).is_null()) return false;
if (info->shared_info()->HasAsmWasmData()) return false;
DCHECK(info->shared_info()->is_compiled());
if (original_code->kind() == Code::FUNCTION) {
// Generating bytecode will install the {InterpreterEntryTrampoline} as
// shared code on the function. To avoid an implicit tier down we restore
// original baseline code in case it existed beforehand.
info->shared_info()->ReplaceCode(*original_code);
}
}
DCHECK(info->shared_info()->HasBytecodeArray());
return true;
}
// TODO(turbofan): In the future, unoptimized code with deopt support could
// be generated lazily once deopt is triggered.
bool Compiler::EnsureDeoptimizationSupport(CompilationInfo* info) {
DCHECK_NOT_NULL(info->literal());
DCHECK_NOT_NULL(info->scope());
Handle<SharedFunctionInfo> shared = info->shared_info();
if (!shared->has_deoptimization_support()) {
Zone zone(info->isolate()->allocator());
CompilationInfo unoptimized(info->parse_info(), info->closure());
unoptimized.EnableDeoptimizationSupport();
// TODO(4280): For now we do not switch generators or async functions to
// baseline code because there might be suspended activations stored in
// generator objects on the heap. We could eventually go directly to
// TurboFan in this case.
if (IsResumableFunction(shared->kind())) return false;
// TODO(4280): For now we disable switching to baseline code in the presence
// of interpreter activations of the given function. The reasons is that the
// underlying bytecode is cleared below. The expensive check for activations
// only needs to be done when the given function has bytecode, otherwise we
// can be sure there are no activations. Note that this only applies in case
// the --ignition-preserve-bytecode flag is not passed.
if (!FLAG_ignition_preserve_bytecode && shared->HasBytecodeArray()) {
InterpreterActivationsFinder activations_finder(*shared);
if (HasInterpreterActivations(info->isolate(), &activations_finder)) {
return false;
}
}
// When we call PrepareForSerializing below, we will change the shared
// ParseInfo. Make sure to reset it.
bool old_will_serialize_value = info->parse_info()->will_serialize();
// If the current code has reloc info for serialization, also include
// reloc info for serialization for the new code, so that deopt support
// can be added without losing IC state.
if (shared->code()->kind() == Code::FUNCTION &&
shared->code()->has_reloc_info_for_serialization()) {
unoptimized.PrepareForSerializing();
}
EnsureFeedbackMetadata(&unoptimized);
if (!FullCodeGenerator::MakeCode(&unoptimized)) return false;
info->parse_info()->set_will_serialize(old_will_serialize_value);
// TODO(4280): For now we play it safe and remove the bytecode array when we
// switch to baseline code. We might consider keeping around the bytecode so
// that it can be used as the "source of truth" eventually. Note that this
// only applies in case the --ignition-preserve-bytecode flag is not passed.
if (!FLAG_ignition_preserve_bytecode && shared->HasBytecodeArray()) {
shared->ClearBytecodeArray();
}
// The scope info might not have been set if a lazily compiled
// function is inlined before being called for the first time.
if (shared->scope_info() == ScopeInfo::Empty(info->isolate())) {
InstallSharedScopeInfo(info, shared);
}
// Install compilation result on the shared function info
shared->EnableDeoptimizationSupport(*unoptimized.code());
// The existing unoptimized code was replaced with the new one.
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG,
&unoptimized);
}
return true;
}
// static
Compiler::CompilationTier Compiler::NextCompilationTier(JSFunction* function) {
Handle<SharedFunctionInfo> shared(function->shared(), function->GetIsolate());
if (shared->code()->is_interpreter_trampoline_builtin()) {
if (FLAG_turbo_from_bytecode && UseTurboFan(shared)) {
return OPTIMIZED;
} else {
return BASELINE;
}
} else {
return OPTIMIZED;
}
}
MaybeHandle<JSFunction> Compiler::GetFunctionFromEval(
Handle<String> source, Handle<SharedFunctionInfo> outer_info,
Handle<Context> context, LanguageMode language_mode,
ParseRestriction restriction, int eval_scope_position, int eval_position,
int line_offset, int column_offset, Handle<Object> script_name,
ScriptOriginOptions options) {
Isolate* isolate = source->GetIsolate();
int source_length = source->length();
isolate->counters()->total_eval_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
CompilationCache* compilation_cache = isolate->compilation_cache();
MaybeHandle<SharedFunctionInfo> maybe_shared_info =
compilation_cache->LookupEval(source, outer_info, context, language_mode,
eval_scope_position);
Handle<SharedFunctionInfo> shared_info;
Handle<Script> script;
if (!maybe_shared_info.ToHandle(&shared_info)) {
script = isolate->factory()->NewScript(source);
if (!script_name.is_null()) {
script->set_name(*script_name);
script->set_line_offset(line_offset);
script->set_column_offset(column_offset);
}
script->set_origin_options(options);
script->set_compilation_type(Script::COMPILATION_TYPE_EVAL);
Script::SetEvalOrigin(script, outer_info, eval_position);
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, script);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
parse_info.set_eval();
parse_info.set_language_mode(language_mode);
parse_info.set_parse_restriction(restriction);
if (!context->IsNativeContext()) {
parse_info.set_outer_scope_info(handle(context->scope_info()));
}
shared_info = CompileToplevel(&info);
if (shared_info.is_null()) {
return MaybeHandle<JSFunction>();
} else {
// 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()));
compilation_cache->PutEval(source, outer_info, context, shared_info,
eval_scope_position);
}
}
Handle<JSFunction> result =
isolate->factory()->NewFunctionFromSharedFunctionInfo(
shared_info, context, NOT_TENURED);
// OnAfterCompile has to be called after we create the JSFunction, which we
// may require to recompile the eval for debugging, if we find a function
// that contains break points in the eval script.
isolate->debug()->OnAfterCompile(script);
return result;
}
namespace {
bool CodeGenerationFromStringsAllowed(Isolate* isolate,
Handle<Context> context) {
DCHECK(context->allow_code_gen_from_strings()->IsFalse(isolate));
// Check with callback if set.
AllowCodeGenerationFromStringsCallback callback =
isolate->allow_code_gen_callback();
if (callback == NULL) {
// No callback set and code generation disallowed.
return false;
} else {
// Callback set. Let it decide if code generation is allowed.
VMState<EXTERNAL> state(isolate);
return callback(v8::Utils::ToLocal(context));
}
}
} // namespace
MaybeHandle<JSFunction> Compiler::GetFunctionFromString(
Handle<Context> context, Handle<String> source,
ParseRestriction restriction) {
Isolate* const isolate = context->GetIsolate();
Handle<Context> native_context(context->native_context(), isolate);
// Check if native context allows code generation from
// strings. Throw an exception if it doesn't.
if (native_context->allow_code_gen_from_strings()->IsFalse(isolate) &&
!CodeGenerationFromStringsAllowed(isolate, native_context)) {
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->closure()->shared());
return Compiler::GetFunctionFromEval(source, outer_info, native_context,
SLOPPY, restriction, eval_scope_position,
eval_position);
}
Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
Handle<String> source, Handle<Object> script_name, int line_offset,
int column_offset, ScriptOriginOptions resource_options,
Handle<Object> source_map_url, Handle<Context> context,
v8::Extension* extension, ScriptData** cached_data,
ScriptCompiler::CompileOptions compile_options, NativesFlag natives,
bool is_module) {
Isolate* isolate = source->GetIsolate();
if (compile_options == ScriptCompiler::kNoCompileOptions) {
cached_data = NULL;
} else if (compile_options == ScriptCompiler::kProduceParserCache ||
compile_options == ScriptCompiler::kProduceCodeCache) {
DCHECK(cached_data && !*cached_data);
DCHECK(extension == NULL);
DCHECK(!isolate->debug()->is_loaded());
} else {
DCHECK(compile_options == ScriptCompiler::kConsumeParserCache ||
compile_options == ScriptCompiler::kConsumeCodeCache);
DCHECK(cached_data && *cached_data);
DCHECK(extension == NULL);
}
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;
Handle<SharedFunctionInfo> result;
if (extension == NULL) {
// First check per-isolate compilation cache.
maybe_result = compilation_cache->LookupScript(
source, script_name, line_offset, column_offset, resource_options,
context, language_mode);
if (maybe_result.is_null() && FLAG_serialize_toplevel &&
compile_options == ScriptCompiler::kConsumeCodeCache &&
!isolate->debug()->is_loaded()) {
// Then check cached code provided by embedder.
HistogramTimerScope timer(isolate->counters()->compile_deserialize());
RuntimeCallTimerScope runtimeTimer(isolate,
&RuntimeCallStats::CompileDeserialize);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CompileDeserialize");
Handle<SharedFunctionInfo> result;
if (CodeSerializer::Deserialize(isolate, *cached_data, source)
.ToHandle(&result)) {
// Promote to per-isolate compilation cache.
compilation_cache->PutScript(source, context, language_mode, result);
return result;
}
// Deserializer failed. Fall through to compile.
}
}
base::ElapsedTimer timer;
if (FLAG_profile_deserialization && FLAG_serialize_toplevel &&
compile_options == ScriptCompiler::kProduceCodeCache) {
timer.Start();
}
if (!maybe_result.ToHandle(&result) ||
(FLAG_serialize_toplevel &&
compile_options == ScriptCompiler::kProduceCodeCache)) {
// No cache entry found, or embedder wants a code cache. Compile the script.
// Create a script object describing the script to be compiled.
Handle<Script> script = isolate->factory()->NewScript(source);
if (natives == NATIVES_CODE) {
script->set_type(Script::TYPE_NATIVE);
script->set_hide_source(true);
} else if (natives == EXTENSION_CODE) {
script->set_type(Script::TYPE_EXTENSION);
script->set_hide_source(true);
}
if (!script_name.is_null()) {
script->set_name(*script_name);
script->set_line_offset(line_offset);
script->set_column_offset(column_offset);
}
script->set_origin_options(resource_options);
if (!source_map_url.is_null()) {
script->set_source_mapping_url(*source_map_url);
}
// Compile the function and add it to the cache.
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, script);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
if (is_module) parse_info.set_module();
if (compile_options != ScriptCompiler::kNoCompileOptions) {
parse_info.set_cached_data(cached_data);
}
parse_info.set_compile_options(compile_options);
parse_info.set_extension(extension);
if (!context->IsNativeContext()) {
parse_info.set_outer_scope_info(handle(context->scope_info()));
}
if (FLAG_serialize_toplevel &&
compile_options == ScriptCompiler::kProduceCodeCache) {
info.PrepareForSerializing();
}
parse_info.set_language_mode(
static_cast<LanguageMode>(parse_info.language_mode() | language_mode));
result = CompileToplevel(&info);
if (extension == NULL && !result.is_null()) {
compilation_cache->PutScript(source, context, language_mode, result);
if (FLAG_serialize_toplevel &&
compile_options == ScriptCompiler::kProduceCodeCache) {
HistogramTimerScope histogram_timer(
isolate->counters()->compile_serialize());
RuntimeCallTimerScope runtimeTimer(isolate,
&RuntimeCallStats::CompileSerialize);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
"V8.CompileSerialize");
*cached_data = CodeSerializer::Serialize(isolate, result, source);
if (FLAG_profile_deserialization) {
PrintF("[Compiling and serializing took %0.3f ms]\n",
timer.Elapsed().InMillisecondsF());
}
}
}
if (result.is_null()) {
isolate->ReportPendingMessages();
} else {
isolate->debug()->OnAfterCompile(script);
}
} else if (result->ic_age() != isolate->heap()->global_ic_age()) {
result->ResetForNewContext(isolate->heap()->global_ic_age());
}
return result;
}
Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForStreamedScript(
Handle<Script> script, ParseInfo* parse_info, int source_length) {
Isolate* isolate = script->GetIsolate();
// TODO(titzer): increment the counters in caller.
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);
parse_info->set_language_mode(
static_cast<LanguageMode>(parse_info->language_mode() | language_mode));
CompilationInfo compile_info(parse_info, Handle<JSFunction>::null());
// The source was parsed lazily, so compiling for debugging is not possible.
DCHECK(!compile_info.is_debug());
Handle<SharedFunctionInfo> result = CompileToplevel(&compile_info);
if (!result.is_null()) isolate->debug()->OnAfterCompile(script);
return result;
}
Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
FunctionLiteral* literal, Handle<Script> script,
CompilationInfo* outer_info) {
// Precondition: code has been parsed and scopes have been analyzed.
Isolate* isolate = outer_info->isolate();
MaybeHandle<SharedFunctionInfo> maybe_existing;
// Find any previously allocated shared function info for the given literal.
if (outer_info->shared_info()->never_compiled()) {
// On the first compile, there are no existing shared function info for
// inner functions yet, so do not try to find them. All bets are off for
// live edit though.
SLOW_DCHECK(script->FindSharedFunctionInfo(literal).is_null() ||
isolate->debug()->live_edit_enabled());
} else {
maybe_existing = script->FindSharedFunctionInfo(literal);
}
// We found an existing shared function info. If it has any sort of code
// attached, don't worry about compiling and simply return it. Otherwise,
// continue to decide whether to eagerly compile.
// Note that we also carry on if we are compiling eager to obtain code for
// debugging, unless we already have code with debug break slots.
Handle<SharedFunctionInfo> existing;
if (maybe_existing.ToHandle(&existing)) {
DCHECK(!existing->is_toplevel());
if (existing->HasBaselineCode() || existing->HasBytecodeArray()) {
if (!outer_info->is_debug() || existing->HasDebugCode()) {
return existing;
}
}
}
// Allocate a shared function info object.
Handle<SharedFunctionInfo> result;
if (!maybe_existing.ToHandle(&result)) {
result = NewSharedFunctionInfoForLiteral(isolate, literal, script);
result->set_is_toplevel(false);
// If the outer function has been compiled before, we cannot be sure that
// shared function info for this function literal has been created for the
// first time. It may have already been compiled previously.
result->set_never_compiled(outer_info->shared_info()->never_compiled());
}
Zone zone(isolate->allocator());
ParseInfo parse_info(&zone, script);
CompilationInfo info(&parse_info, Handle<JSFunction>::null());
parse_info.set_literal(literal);
parse_info.set_shared_info(result);
parse_info.set_language_mode(literal->scope()->language_mode());
if (outer_info->will_serialize()) info.PrepareForSerializing();
if (outer_info->is_debug()) info.MarkAsDebug();
// Generate code
TimerEventScope<TimerEventCompileCode> timer(isolate);
RuntimeCallTimerScope runtimeTimer(isolate, &RuntimeCallStats::CompileCode);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileCode");
if (!literal->ShouldEagerCompile()) {
info.SetCode(isolate->builtins()->CompileLazy());
Scope* outer_scope = literal->scope()->GetOuterScopeWithContext();
if (outer_scope) {
result->set_outer_scope_info(*outer_scope->scope_info());
}
} else if (Renumber(info.parse_info()) && GenerateUnoptimizedCode(&info)) {
// Code generation will ensure that the feedback vector is present and
// appropriately sized.
DCHECK(!info.code().is_null());
if (literal->should_be_used_once_hint()) {
info.code()->MarkToBeExecutedOnce(isolate);
}
} else {
return Handle<SharedFunctionInfo>::null();
}
if (maybe_existing.is_null()) {
RecordFunctionCompilation(CodeEventListener::FUNCTION_TAG, &info);
}
return result;
}
Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForNative(
v8::Extension* extension, Handle<String> name) {
Isolate* isolate = name->GetIsolate();
v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate);
// Compute the function template for the native function.
v8::Local<v8::FunctionTemplate> fun_template =
extension->GetNativeFunctionTemplate(v8_isolate,
v8::Utils::ToLocal(name));
DCHECK(!fun_template.IsEmpty());
// Instantiate the function and create a shared function info from it.
Handle<JSFunction> fun = Handle<JSFunction>::cast(Utils::OpenHandle(
*fun_template->GetFunction(v8_isolate->GetCurrentContext())
.ToLocalChecked()));
Handle<Code> code = Handle<Code>(fun->shared()->code());
Handle<Code> construct_stub = Handle<Code>(fun->shared()->construct_stub());
Handle<SharedFunctionInfo> shared = isolate->factory()->NewSharedFunctionInfo(
name, fun->shared()->num_literals(), FunctionKind::kNormalFunction, code,
Handle<ScopeInfo>(fun->shared()->scope_info()));
shared->set_outer_scope_info(fun->shared()->outer_scope_info());
shared->SetConstructStub(*construct_stub);
shared->set_feedback_metadata(fun->shared()->feedback_metadata());
// Copy the function data to the shared function info.
shared->set_function_data(fun->shared()->function_data());
int parameters = fun->shared()->internal_formal_parameter_count();
shared->set_internal_formal_parameter_count(parameters);
return shared;
}
MaybeHandle<Code> Compiler::GetOptimizedCodeForOSR(Handle<JSFunction> function,
BailoutId osr_ast_id,
JavaScriptFrame* osr_frame) {
DCHECK(!osr_ast_id.IsNone());
DCHECK_NOT_NULL(osr_frame);
return GetOptimizedCode(function, NOT_CONCURRENT, osr_ast_id, osr_frame);
}
CompilationJob* Compiler::PrepareUnoptimizedCompilationJob(
CompilationInfo* info) {
VMState<COMPILER> state(info->isolate());
std::unique_ptr<CompilationJob> job(GetUnoptimizedCompilationJob(info));
if (job->PrepareJob() != CompilationJob::SUCCEEDED) {
return nullptr;
}
return job.release();
}
bool Compiler::FinalizeCompilationJob(CompilationJob* raw_job) {
// Take ownership of compilation job. Deleting job also tears down the zone.
std::unique_ptr<CompilationJob> job(raw_job);
VMState<COMPILER> state(job->info()->isolate());
if (job->info()->IsOptimizing()) {
return FinalizeOptimizedCompilationJob(job.get()) ==
CompilationJob::SUCCEEDED;
} else {
if (FinalizeUnoptimizedCompilationJob(job.get()) ==
CompilationJob::SUCCEEDED) {
RecordFunctionCompilation(CodeEventListener::LAZY_COMPILE_TAG,
job->info());
return true;
}
return false;
}
}
void Compiler::PostInstantiation(Handle<JSFunction> function,
PretenureFlag pretenure) {
Handle<SharedFunctionInfo> shared(function->shared());
if (FLAG_always_opt && shared->allows_lazy_compilation()) {
function->MarkForOptimization();
}
CodeAndLiterals cached = shared->SearchOptimizedCodeMap(
function->context()->native_context(), BailoutId::None());
if (cached.code != nullptr) {
// Caching of optimized code enabled and optimized code found.
DCHECK(!cached.code->marked_for_deoptimization());
DCHECK(function->shared()->is_compiled());
function->ReplaceCode(cached.code);
}
if (cached.literals != nullptr) {
DCHECK(shared->is_compiled());
function->set_literals(cached.literals);
} else if (shared->is_compiled()) {
// TODO(mvstanton): pass pretenure flag to EnsureLiterals.
JSFunction::EnsureLiterals(function);
}
}
} // namespace internal
} // namespace v8