src/v8/src/compiler.cc

   1 // Copyright 2012 the V8 project authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "src/v8.h"
   6
   7 #include "src/compiler.h"
   8
   9 #include "src/bootstrapper.h"
  10 #include "src/codegen.h"
  11 #include "src/compilation-cache.h"
  12 #include "src/cpu-profiler.h"
  13 #include "src/debug.h"
  14 #include "src/deoptimizer.h"
  15 #include "src/full-codegen.h"
  16 #include "src/gdb-jit.h"
  17 #include "src/typing.h"
  18 #include "src/hydrogen.h"
  19 #include "src/isolate-inl.h"
  20 #include "src/lithium.h"
  21 #include "src/liveedit.h"
  22 #include "src/parser.h"
  23 #include "src/rewriter.h"
  24 #include "src/runtime-profiler.h"
  25 #include "src/scanner-character-streams.h"
  26 #include "src/scopeinfo.h"
  27 #include "src/scopes.h"
  28 #include "src/vm-state-inl.h"
  29
  30 namespace v8 {
  31 namespace internal {
  32
  33
  34 CompilationInfo::CompilationInfo(Handle<Script> script,
  35                                  Zone* zone)
  36     : flags_(StrictModeField::encode(SLOPPY)),
  37       script_(script),
  38       osr_ast_id_(BailoutId::None()),
  39       parameter_count_(0),
  40       this_has_uses_(true),
  41       optimization_id_(-1) {
  42   Initialize(script->GetIsolate(), BASE, zone);
  43 }
  44
  45
  46 CompilationInfo::CompilationInfo(Handle<SharedFunctionInfo> shared_info,
  47                                  Zone* zone)
  48     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
  49       shared_info_(shared_info),
  50       script_(Handle<Script>(Script::cast(shared_info->script()))),
  51       osr_ast_id_(BailoutId::None()),
  52       parameter_count_(0),
  53       this_has_uses_(true),
  54       optimization_id_(-1) {
  55   Initialize(script_->GetIsolate(), BASE, zone);
  56 }
  57
  58
  59 CompilationInfo::CompilationInfo(Handle<JSFunction> closure,
  60                                  Zone* zone)
  61     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
  62       closure_(closure),
  63       shared_info_(Handle<SharedFunctionInfo>(closure->shared())),
  64       script_(Handle<Script>(Script::cast(shared_info_->script()))),
  65       context_(closure->context()),
  66       osr_ast_id_(BailoutId::None()),
  67       parameter_count_(0),
  68       this_has_uses_(true),
  69       optimization_id_(-1) {
  70   Initialize(script_->GetIsolate(), BASE, zone);
  71 }
  72
  73
  74 CompilationInfo::CompilationInfo(HydrogenCodeStub* stub,
  75                                  Isolate* isolate,
  76                                  Zone* zone)
  77     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
  78       osr_ast_id_(BailoutId::None()),
  79       parameter_count_(0),
  80       this_has_uses_(true),
  81       optimization_id_(-1) {
  82   Initialize(isolate, STUB, zone);
  83   code_stub_ = stub;
  84 }
  85
  86
  87 void CompilationInfo::Initialize(Isolate* isolate,
  88                                  Mode mode,
  89                                  Zone* zone) {
  90   isolate_ = isolate;
  91   function_ = NULL;
  92   scope_ = NULL;
  93   global_scope_ = NULL;
  94   extension_ = NULL;
  95   cached_data_ = NULL;
  96   cached_data_mode_ = NO_CACHED_DATA;
  97   zone_ = zone;
  98   deferred_handles_ = NULL;
  99   code_stub_ = NULL;
 100   prologue_offset_ = Code::kPrologueOffsetNotSet;
 101   opt_count_ = shared_info().is_null() ? 0 : shared_info()->opt_count();
 102   no_frame_ranges_ = isolate->cpu_profiler()->is_profiling()
 103                    ? new List<OffsetRange>(2) : NULL;
 104   for (int i = 0; i < DependentCode::kGroupCount; i++) {
 105     dependencies_[i] = NULL;
 106   }
 107   if (mode == STUB) {
 108     mode_ = STUB;
 109     return;
 110   }
 111   mode_ = mode;
 112   abort_due_to_dependency_ = false;
 113   if (script_->type()->value() == Script::TYPE_NATIVE) MarkAsNative();
 114   if (isolate_->debug()->is_active()) MarkAsDebug();
 115
 116   if (!shared_info_.is_null()) {
 117     ASSERT(strict_mode() == SLOPPY);
 118     SetStrictMode(shared_info_->strict_mode());
 119   }
 120   set_bailout_reason(kUnknown);
 121
 122   if (!shared_info().is_null() && shared_info()->is_compiled()) {
 123     // We should initialize the CompilationInfo feedback vector from the
 124     // passed in shared info, rather than creating a new one.
 125     feedback_vector_ = Handle<FixedArray>(shared_info()->feedback_vector(),
 126                                           isolate);
 127   }
 128 }
 129
 130
 131 CompilationInfo::~CompilationInfo() {
 132   delete deferred_handles_;
 133   delete no_frame_ranges_;
 134 #ifdef DEBUG
 135   // Check that no dependent maps have been added or added dependent maps have
 136   // been rolled back or committed.
 137   for (int i = 0; i < DependentCode::kGroupCount; i++) {
 138     ASSERT_EQ(NULL, dependencies_[i]);
 139   }
 140 #endif  // DEBUG
 141 }
 142
 143
 144 void CompilationInfo::CommitDependencies(Handle<Code> code) {
 145   for (int i = 0; i < DependentCode::kGroupCount; i++) {
 146     ZoneList<Handle<HeapObject> >* group_objects = dependencies_[i];
 147     if (group_objects == NULL) continue;
 148     ASSERT(!object_wrapper_.is_null());
 149     for (int j = 0; j < group_objects->length(); j++) {
 150       DependentCode::DependencyGroup group =
 151           static_cast<DependentCode::DependencyGroup>(i);
 152       DependentCode* dependent_code =
 153           DependentCode::ForObject(group_objects->at(j), group);
 154       dependent_code->UpdateToFinishedCode(group, this, *code);
 155     }
 156     dependencies_[i] = NULL;  // Zone-allocated, no need to delete.
 157   }
 158 }
 159
 160
 161 void CompilationInfo::RollbackDependencies() {
 162   // Unregister from all dependent maps if not yet committed.
 163   for (int i = 0; i < DependentCode::kGroupCount; i++) {
 164     ZoneList<Handle<HeapObject> >* group_objects = dependencies_[i];
 165     if (group_objects == NULL) continue;
 166     for (int j = 0; j < group_objects->length(); j++) {
 167       DependentCode::DependencyGroup group =
 168           static_cast<DependentCode::DependencyGroup>(i);
 169       DependentCode* dependent_code =
 170           DependentCode::ForObject(group_objects->at(j), group);
 171       dependent_code->RemoveCompilationInfo(group, this);
 172     }
 173     dependencies_[i] = NULL;  // Zone-allocated, no need to delete.
 174   }
 175 }
 176
 177
 178 int CompilationInfo::num_parameters() const {
 179   if (IsStub()) {
 180     ASSERT(parameter_count_ > 0);
 181     return parameter_count_;
 182   } else {
 183     return scope()->num_parameters();
 184   }
 185 }
 186
 187
 188 int CompilationInfo::num_heap_slots() const {
 189   if (IsStub()) {
 190     return 0;
 191   } else {
 192     return scope()->num_heap_slots();
 193   }
 194 }
 195
 196
 197 Code::Flags CompilationInfo::flags() const {
 198   if (IsStub()) {
 199     return Code::ComputeFlags(code_stub()->GetCodeKind(),
 200                               code_stub()->GetICState(),
 201                               code_stub()->GetExtraICState(),
 202                               code_stub()->GetStubType());
 203   } else {
 204     return Code::ComputeFlags(Code::OPTIMIZED_FUNCTION);
 205   }
 206 }
 207
 208
 209 // Disable optimization for the rest of the compilation pipeline.
 210 void CompilationInfo::DisableOptimization() {
 211   bool is_optimizable_closure =
 212     FLAG_optimize_closures &&
 213     closure_.is_null() &&
 214     !scope_->HasTrivialOuterContext() &&
 215     !scope_->outer_scope_calls_sloppy_eval() &&
 216     !scope_->inside_with();
 217   SetMode(is_optimizable_closure ? BASE : NONOPT);
 218 }
 219
 220
 221 // Primitive functions are unlikely to be picked up by the stack-walking
 222 // profiler, so they trigger their own optimization when they're called
 223 // for the SharedFunctionInfo::kCallsUntilPrimitiveOptimization-th time.
 224 bool CompilationInfo::ShouldSelfOptimize() {
 225   return FLAG_crankshaft &&
 226       !function()->flags()->Contains(kDontSelfOptimize) &&
 227       !function()->dont_optimize() &&
 228       function()->scope()->AllowsLazyCompilation() &&
 229       (shared_info().is_null() || !shared_info()->optimization_disabled());
 230 }
 231
 232
 233 void CompilationInfo::PrepareForCompilation(Scope* scope) {
 234   ASSERT(scope_ == NULL);
 235   scope_ = scope;
 236
 237   int length = function()->slot_count();
 238   if (feedback_vector_.is_null()) {
 239     // Allocate the feedback vector too.
 240     feedback_vector_ = isolate()->factory()->NewTypeFeedbackVector(length);
 241   }
 242   ASSERT(feedback_vector_->length() == length);
 243 }
 244
 245
 246 class HOptimizedGraphBuilderWithPositions: public HOptimizedGraphBuilder {
 247  public:
 248   explicit HOptimizedGraphBuilderWithPositions(CompilationInfo* info)
 249       : HOptimizedGraphBuilder(info) {
 250   }
 251
 252 #define DEF_VISIT(type)                                 \
 253   virtual void Visit##type(type* node) V8_OVERRIDE {    \
 254     if (node->position() != RelocInfo::kNoPosition) {   \
 255       SetSourcePosition(node->position());              \
 256     }                                                   \
 257     HOptimizedGraphBuilder::Visit##type(node);          \
 258   }
 259   EXPRESSION_NODE_LIST(DEF_VISIT)
 260 #undef DEF_VISIT
 261
 262 #define DEF_VISIT(type)                                          \
 263   virtual void Visit##type(type* node) V8_OVERRIDE {             \
 264     if (node->position() != RelocInfo::kNoPosition) {            \
 265       SetSourcePosition(node->position());                       \
 266     }                                                            \
 267     HOptimizedGraphBuilder::Visit##type(node);                   \
 268   }
 269   STATEMENT_NODE_LIST(DEF_VISIT)
 270 #undef DEF_VISIT
 271
 272 #define DEF_VISIT(type)                                            \
 273   virtual void Visit##type(type* node) V8_OVERRIDE {               \
 274     HOptimizedGraphBuilder::Visit##type(node);                     \
 275   }
 276   MODULE_NODE_LIST(DEF_VISIT)
 277   DECLARATION_NODE_LIST(DEF_VISIT)
 278 #undef DEF_VISIT
 279 };
 280
 281
 282 OptimizedCompileJob::Status OptimizedCompileJob::CreateGraph() {
 283   ASSERT(isolate()->use_crankshaft());
 284   ASSERT(info()->IsOptimizing());
 285   ASSERT(!info()->IsCompilingForDebugging());
 286
 287   // We should never arrive here if there is no code object on the
 288   // shared function object.
 289   ASSERT(info()->shared_info()->code()->kind() == Code::FUNCTION);
 290
 291   // We should never arrive here if optimization has been disabled on the
 292   // shared function info.
 293   ASSERT(!info()->shared_info()->optimization_disabled());
 294
 295   // Fall back to using the full code generator if it's not possible
 296   // to use the Hydrogen-based optimizing compiler. We already have
 297   // generated code for this from the shared function object.
 298   if (FLAG_always_full_compiler) return AbortOptimization();
 299
 300   // Do not use crankshaft if we need to be able to set break points.
 301   if (isolate()->DebuggerHasBreakPoints()) {
 302     return AbortOptimization(kDebuggerHasBreakPoints);
 303   }
 304
 305   // Limit the number of times we re-compile a functions with
 306   // the optimizing compiler.
 307   const int kMaxOptCount =
 308       FLAG_deopt_every_n_times == 0 ? FLAG_max_opt_count : 1000;
 309   if (info()->opt_count() > kMaxOptCount) {
 310     return AbortAndDisableOptimization(kOptimizedTooManyTimes);
 311   }
 312
 313   // Due to an encoding limit on LUnallocated operands in the Lithium
 314   // language, we cannot optimize functions with too many formal parameters
 315   // or perform on-stack replacement for function with too many
 316   // stack-allocated local variables.
 317   //
 318   // The encoding is as a signed value, with parameters and receiver using
 319   // the negative indices and locals the non-negative ones.
 320   const int parameter_limit = -LUnallocated::kMinFixedSlotIndex;
 321   Scope* scope = info()->scope();
 322   if ((scope->num_parameters() + 1) > parameter_limit) {
 323     return AbortAndDisableOptimization(kTooManyParameters);
 324   }
 325
 326   const int locals_limit = LUnallocated::kMaxFixedSlotIndex;
 327   if (info()->is_osr() &&
 328       scope->num_parameters() + 1 + scope->num_stack_slots() > locals_limit) {
 329     return AbortAndDisableOptimization(kTooManyParametersLocals);
 330   }
 331
 332   if (scope->HasIllegalRedeclaration()) {
 333     return AbortAndDisableOptimization(kFunctionWithIllegalRedeclaration);
 334   }
 335
 336   // Take --hydrogen-filter into account.
 337   if (!info()->closure()->PassesFilter(FLAG_hydrogen_filter)) {
 338     return AbortOptimization(kHydrogenFilter);
 339   }
 340
 341   // Recompile the unoptimized version of the code if the current version
 342   // doesn't have deoptimization support. Alternatively, we may decide to
 343   // run the full code generator to get a baseline for the compile-time
 344   // performance of the hydrogen-based compiler.
 345   bool should_recompile = !info()->shared_info()->has_deoptimization_support();
 346   if (should_recompile || FLAG_hydrogen_stats) {
 347     ElapsedTimer timer;
 348     if (FLAG_hydrogen_stats) {
 349       timer.Start();
 350     }
 351     CompilationInfoWithZone unoptimized(info()->shared_info());
 352     // Note that we use the same AST that we will use for generating the
 353     // optimized code.
 354     unoptimized.SetFunction(info()->function());
 355     unoptimized.PrepareForCompilation(info()->scope());
 356     unoptimized.SetContext(info()->context());
 357     if (should_recompile) unoptimized.EnableDeoptimizationSupport();
 358     bool succeeded = FullCodeGenerator::MakeCode(&unoptimized);
 359     if (should_recompile) {
 360       if (!succeeded) return SetLastStatus(FAILED);
 361       Handle<SharedFunctionInfo> shared = info()->shared_info();
 362       shared->EnableDeoptimizationSupport(*unoptimized.code());
 363       // The existing unoptimized code was replaced with the new one.
 364       Compiler::RecordFunctionCompilation(
 365           Logger::LAZY_COMPILE_TAG, &unoptimized, shared);
 366     }
 367     if (FLAG_hydrogen_stats) {
 368       isolate()->GetHStatistics()->IncrementFullCodeGen(timer.Elapsed());
 369     }
 370   }
 371
 372   // Check that the unoptimized, shared code is ready for
 373   // optimizations.  When using the always_opt flag we disregard the
 374   // optimizable marker in the code object and optimize anyway. This
 375   // is safe as long as the unoptimized code has deoptimization
 376   // support.
 377   ASSERT(FLAG_always_opt || info()->shared_info()->code()->optimizable());
 378   ASSERT(info()->shared_info()->has_deoptimization_support());
 379
 380   if (FLAG_trace_hydrogen) {
 381     Handle<String> name = info()->function()->debug_name();
 382     PrintF("-----------------------------------------------------------\n");
 383     PrintF("Compiling method %s using hydrogen\n", name->ToCString().get());
 384     isolate()->GetHTracer()->TraceCompilation(info());
 385   }
 386
 387   // Type-check the function.
 388   AstTyper::Run(info());
 389
 390   graph_builder_ = FLAG_hydrogen_track_positions
 391       ? new(info()->zone()) HOptimizedGraphBuilderWithPositions(info())
 392       : new(info()->zone()) HOptimizedGraphBuilder(info());
 393
 394   Timer t(this, &time_taken_to_create_graph_);
 395   info()->set_this_has_uses(false);
 396   graph_ = graph_builder_->CreateGraph();
 397
 398   if (isolate()->has_pending_exception()) {
 399     return SetLastStatus(FAILED);
 400   }
 401
 402   // The function being compiled may have bailed out due to an inline
 403   // candidate bailing out.  In such a case, we don't disable
 404   // optimization on the shared_info.
 405   ASSERT(!graph_builder_->inline_bailout() || graph_ == NULL);
 406   if (graph_ == NULL) {
 407     if (graph_builder_->inline_bailout()) {
 408       return AbortOptimization();
 409     } else {
 410       return AbortAndDisableOptimization();
 411     }
 412   }
 413
 414   if (info()->HasAbortedDueToDependencyChange()) {
 415     return AbortOptimization(kBailedOutDueToDependencyChange);
 416   }
 417
 418   return SetLastStatus(SUCCEEDED);
 419 }
 420
 421
 422 OptimizedCompileJob::Status OptimizedCompileJob::OptimizeGraph() {
 423   DisallowHeapAllocation no_allocation;
 424   DisallowHandleAllocation no_handles;
 425   DisallowHandleDereference no_deref;
 426   DisallowCodeDependencyChange no_dependency_change;
 427
 428   ASSERT(last_status() == SUCCEEDED);
 429   Timer t(this, &time_taken_to_optimize_);
 430   ASSERT(graph_ != NULL);
 431   BailoutReason bailout_reason = kNoReason;
 432
 433   if (graph_->Optimize(&bailout_reason)) {
 434     chunk_ = LChunk::NewChunk(graph_);
 435     if (chunk_ != NULL) return SetLastStatus(SUCCEEDED);
 436   } else if (bailout_reason != kNoReason) {
 437     graph_builder_->Bailout(bailout_reason);
 438   }
 439
 440   return AbortOptimization();
 441 }
 442
 443
 444 OptimizedCompileJob::Status OptimizedCompileJob::GenerateCode() {
 445   ASSERT(last_status() == SUCCEEDED);
 446   ASSERT(!info()->HasAbortedDueToDependencyChange());
 447   DisallowCodeDependencyChange no_dependency_change;
 448   {  // Scope for timer.
 449     Timer timer(this, &time_taken_to_codegen_);
 450     ASSERT(chunk_ != NULL);
 451     ASSERT(graph_ != NULL);
 452     // Deferred handles reference objects that were accessible during
 453     // graph creation.  To make sure that we don't encounter inconsistencies
 454     // between graph creation and code generation, we disallow accessing
 455     // objects through deferred handles during the latter, with exceptions.
 456     DisallowDeferredHandleDereference no_deferred_handle_deref;
 457     Handle<Code> optimized_code = chunk_->Codegen();
 458     if (optimized_code.is_null()) {
 459       if (info()->bailout_reason() == kNoReason) {
 460         info_->set_bailout_reason(kCodeGenerationFailed);
 461       } else if (info()->bailout_reason() == kMapBecameDeprecated) {
 462         if (FLAG_trace_opt) {
 463           PrintF("[aborted optimizing ");
 464           info()->closure()->ShortPrint();
 465           PrintF(" because a map became deprecated]\n");
 466         }
 467         return AbortOptimization();
 468       } else if (info()->bailout_reason() == kMapBecameUnstable) {
 469         if (FLAG_trace_opt) {
 470           PrintF("[aborted optimizing ");
 471           info()->closure()->ShortPrint();
 472           PrintF(" because a map became unstable]\n");
 473         }
 474         return AbortOptimization();
 475       }
 476       return AbortAndDisableOptimization();
 477     }
 478     info()->SetCode(optimized_code);
 479   }
 480   RecordOptimizationStats();
 481   // Add to the weak list of optimized code objects.
 482   info()->context()->native_context()->AddOptimizedCode(*info()->code());
 483   return SetLastStatus(SUCCEEDED);
 484 }
 485
 486
 487 void OptimizedCompileJob::RecordOptimizationStats() {
 488   Handle<JSFunction> function = info()->closure();
 489   if (!function->IsOptimized()) {
 490     // Concurrent recompilation and OSR may race.  Increment only once.
 491     int opt_count = function->shared()->opt_count();
 492     function->shared()->set_opt_count(opt_count + 1);
 493   }
 494   double ms_creategraph = time_taken_to_create_graph_.InMillisecondsF();
 495   double ms_optimize = time_taken_to_optimize_.InMillisecondsF();
 496   double ms_codegen = time_taken_to_codegen_.InMillisecondsF();
 497   if (FLAG_trace_opt) {
 498     PrintF("[optimizing ");
 499     function->ShortPrint();
 500     PrintF(" - took %0.3f, %0.3f, %0.3f ms]\n", ms_creategraph, ms_optimize,
 501            ms_codegen);
 502   }
 503   if (FLAG_trace_opt_stats) {
 504     static double compilation_time = 0.0;
 505     static int compiled_functions = 0;
 506     static int code_size = 0;
 507
 508     compilation_time += (ms_creategraph + ms_optimize + ms_codegen);
 509     compiled_functions++;
 510     code_size += function->shared()->SourceSize();
 511     PrintF("Compiled: %d functions with %d byte source size in %fms.\n",
 512            compiled_functions,
 513            code_size,
 514            compilation_time);
 515   }
 516   if (FLAG_hydrogen_stats) {
 517     isolate()->GetHStatistics()->IncrementSubtotals(time_taken_to_create_graph_,
 518                                                     time_taken_to_optimize_,
 519                                                     time_taken_to_codegen_);
 520   }
 521 }
 522
 523
 524 // Sets the expected number of properties based on estimate from compiler.
 525 void SetExpectedNofPropertiesFromEstimate(Handle<SharedFunctionInfo> shared,
 526                                           int estimate) {
 527   // If no properties are added in the constructor, they are more likely
 528   // to be added later.
 529   if (estimate == 0) estimate = 2;
 530
 531   // TODO(yangguo): check whether those heuristics are still up-to-date.
 532   // We do not shrink objects that go into a snapshot (yet), so we adjust
 533   // the estimate conservatively.
 534   if (shared->GetIsolate()->serializer_enabled()) {
 535     estimate += 2;
 536   } else if (FLAG_clever_optimizations) {
 537     // Inobject slack tracking will reclaim redundant inobject space later,
 538     // so we can afford to adjust the estimate generously.
 539     estimate += 8;
 540   } else {
 541     estimate += 3;
 542   }
 543
 544   shared->set_expected_nof_properties(estimate);
 545 }
 546
 547
 548 static void UpdateSharedFunctionInfo(CompilationInfo* info) {
 549   // Update the shared function info with the compiled code and the
 550   // scope info.  Please note, that the order of the shared function
 551   // info initialization is important since set_scope_info might
 552   // trigger a GC, causing the ASSERT below to be invalid if the code
 553   // was flushed. By setting the code object last we avoid this.
 554   Handle<SharedFunctionInfo> shared = info->shared_info();
 555   Handle<ScopeInfo> scope_info =
 556       ScopeInfo::Create(info->scope(), info->zone());
 557   shared->set_scope_info(*scope_info);
 558
 559   Handle<Code> code = info->code();
 560   CHECK(code->kind() == Code::FUNCTION);
 561   shared->ReplaceCode(*code);
 562   if (shared->optimization_disabled()) code->set_optimizable(false);
 563
 564   shared->set_feedback_vector(*info->feedback_vector());
 565
 566   // Set the expected number of properties for instances.
 567   FunctionLiteral* lit = info->function();
 568   int expected = lit->expected_property_count();
 569   SetExpectedNofPropertiesFromEstimate(shared, expected);
 570
 571   // Check the function has compiled code.
 572   ASSERT(shared->is_compiled());
 573   shared->set_dont_optimize_reason(lit->dont_optimize_reason());
 574   shared->set_dont_inline(lit->flags()->Contains(kDontInline));
 575   shared->set_ast_node_count(lit->ast_node_count());
 576   shared->set_strict_mode(lit->strict_mode());
 577 }
 578
 579
 580 // Sets the function info on a function.
 581 // The start_position points to the first '(' character after the function name
 582 // in the full script source. When counting characters in the script source the
 583 // the first character is number 0 (not 1).
 584 static void SetFunctionInfo(Handle<SharedFunctionInfo> function_info,
 585                             FunctionLiteral* lit,
 586                             bool is_toplevel,
 587                             Handle<Script> script) {
 588   function_info->set_length(lit->parameter_count());
 589   function_info->set_formal_parameter_count(lit->parameter_count());
 590   function_info->set_script(*script);
 591   function_info->set_function_token_position(lit->function_token_position());
 592   function_info->set_start_position(lit->start_position());
 593   function_info->set_end_position(lit->end_position());
 594   function_info->set_is_expression(lit->is_expression());
 595   function_info->set_is_anonymous(lit->is_anonymous());
 596   function_info->set_is_toplevel(is_toplevel);
 597   function_info->set_inferred_name(*lit->inferred_name());
 598   function_info->set_allows_lazy_compilation(lit->AllowsLazyCompilation());
 599   function_info->set_allows_lazy_compilation_without_context(
 600       lit->AllowsLazyCompilationWithoutContext());
 601   function_info->set_strict_mode(lit->strict_mode());
 602   function_info->set_uses_arguments(lit->scope()->arguments() != NULL);
 603   function_info->set_has_duplicate_parameters(lit->has_duplicate_parameters());
 604   function_info->set_ast_node_count(lit->ast_node_count());
 605   function_info->set_is_function(lit->is_function());
 606   function_info->set_dont_optimize_reason(lit->dont_optimize_reason());
 607   function_info->set_dont_inline(lit->flags()->Contains(kDontInline));
 608   function_info->set_dont_cache(lit->flags()->Contains(kDontCache));
 609   function_info->set_is_generator(lit->is_generator());
 610 }
 611
 612
 613 static bool CompileUnoptimizedCode(CompilationInfo* info) {
 614   ASSERT(info->function() != NULL);
 615   if (!Rewriter::Rewrite(info)) return false;
 616   if (!Scope::Analyze(info)) return false;
 617   ASSERT(info->scope() != NULL);
 618
 619   if (!FullCodeGenerator::MakeCode(info)) {
 620     Isolate* isolate = info->isolate();
 621     if (!isolate->has_pending_exception()) isolate->StackOverflow();
 622     return false;
 623   }
 624   return true;
 625 }
 626
 627
 628 MUST_USE_RESULT static MaybeHandle<Code> GetUnoptimizedCodeCommon(
 629     CompilationInfo* info) {
 630   VMState<COMPILER> state(info->isolate());
 631   PostponeInterruptsScope postpone(info->isolate());
 632   if (!Parser::Parse(info)) return MaybeHandle<Code>();
 633   info->SetStrictMode(info->function()->strict_mode());
 634
 635   if (!CompileUnoptimizedCode(info)) return MaybeHandle<Code>();
 636   Compiler::RecordFunctionCompilation(
 637       Logger::LAZY_COMPILE_TAG, info, info->shared_info());
 638   UpdateSharedFunctionInfo(info);
 639   ASSERT_EQ(Code::FUNCTION, info->code()->kind());
 640   return info->code();
 641 }
 642
 643
 644 MaybeHandle<Code> Compiler::GetUnoptimizedCode(Handle<JSFunction> function) {
 645   ASSERT(!function->GetIsolate()->has_pending_exception());
 646   ASSERT(!function->is_compiled());
 647   if (function->shared()->is_compiled()) {
 648     return Handle<Code>(function->shared()->code());
 649   }
 650
 651   CompilationInfoWithZone info(function);
 652   Handle<Code> result;
 653   ASSIGN_RETURN_ON_EXCEPTION(info.isolate(), result,
 654                              GetUnoptimizedCodeCommon(&info),
 655                              Code);
 656
 657   if (FLAG_always_opt &&
 658       info.isolate()->use_crankshaft() &&
 659       !info.shared_info()->optimization_disabled() &&
 660       !info.isolate()->DebuggerHasBreakPoints()) {
 661     Handle<Code> opt_code;
 662     if (Compiler::GetOptimizedCode(
 663             function, result,
 664             Compiler::NOT_CONCURRENT).ToHandle(&opt_code)) {
 665       result = opt_code;
 666     }
 667   }
 668
 669   return result;
 670 }
 671
 672
 673 MaybeHandle<Code> Compiler::GetUnoptimizedCode(
 674     Handle<SharedFunctionInfo> shared) {
 675   ASSERT(!shared->GetIsolate()->has_pending_exception());
 676   ASSERT(!shared->is_compiled());
 677
 678   CompilationInfoWithZone info(shared);
 679   return GetUnoptimizedCodeCommon(&info);
 680 }
 681
 682
 683 bool Compiler::EnsureCompiled(Handle<JSFunction> function,
 684                               ClearExceptionFlag flag) {
 685   if (function->is_compiled()) return true;
 686   MaybeHandle<Code> maybe_code = Compiler::GetUnoptimizedCode(function);
 687   Handle<Code> code;
 688   if (!maybe_code.ToHandle(&code)) {
 689     if (flag == CLEAR_EXCEPTION) {
 690       function->GetIsolate()->clear_pending_exception();
 691     }
 692     return false;
 693   }
 694   function->ReplaceCode(*code);
 695   ASSERT(function->is_compiled());
 696   return true;
 697 }
 698
 699
 700 // Compile full code for debugging. This code will have debug break slots
 701 // and deoptimization information. Deoptimization information is required
 702 // in case that an optimized version of this function is still activated on
 703 // the stack. It will also make sure that the full code is compiled with
 704 // the same flags as the previous version, that is flags which can change
 705 // the code generated. The current method of mapping from already compiled
 706 // full code without debug break slots to full code with debug break slots
 707 // depends on the generated code is otherwise exactly the same.
 708 // If compilation fails, just keep the existing code.
 709 MaybeHandle<Code> Compiler::GetCodeForDebugging(Handle<JSFunction> function) {
 710   CompilationInfoWithZone info(function);
 711   Isolate* isolate = info.isolate();
 712   VMState<COMPILER> state(isolate);
 713
 714   info.MarkAsDebug();
 715
 716   ASSERT(!isolate->has_pending_exception());
 717   Handle<Code> old_code(function->shared()->code());
 718   ASSERT(old_code->kind() == Code::FUNCTION);
 719   ASSERT(!old_code->has_debug_break_slots());
 720
 721   info.MarkCompilingForDebugging();
 722   if (old_code->is_compiled_optimizable()) {
 723     info.EnableDeoptimizationSupport();
 724   } else {
 725     info.MarkNonOptimizable();
 726   }
 727   MaybeHandle<Code> maybe_new_code = GetUnoptimizedCodeCommon(&info);
 728   Handle<Code> new_code;
 729   if (!maybe_new_code.ToHandle(&new_code)) {
 730     isolate->clear_pending_exception();
 731   } else {
 732     ASSERT_EQ(old_code->is_compiled_optimizable(),
 733               new_code->is_compiled_optimizable());
 734   }
 735   return maybe_new_code;
 736 }
 737
 738
 739 void Compiler::CompileForLiveEdit(Handle<Script> script) {
 740   // TODO(635): support extensions.
 741   CompilationInfoWithZone info(script);
 742   PostponeInterruptsScope postpone(info.isolate());
 743   VMState<COMPILER> state(info.isolate());
 744
 745   info.MarkAsGlobal();
 746   if (!Parser::Parse(&info)) return;
 747   info.SetStrictMode(info.function()->strict_mode());
 748
 749   LiveEditFunctionTracker tracker(info.isolate(), info.function());
 750   if (!CompileUnoptimizedCode(&info)) return;
 751   if (!info.shared_info().is_null()) {
 752     Handle<ScopeInfo> scope_info = ScopeInfo::Create(info.scope(),
 753                                                      info.zone());
 754     info.shared_info()->set_scope_info(*scope_info);
 755   }
 756   tracker.RecordRootFunctionInfo(info.code());
 757 }
 758
 759
 760 static bool DebuggerWantsEagerCompilation(CompilationInfo* info,
 761                                           bool allow_lazy_without_ctx = false) {
 762   return LiveEditFunctionTracker::IsActive(info->isolate()) ||
 763          (info->isolate()->DebuggerHasBreakPoints() && !allow_lazy_without_ctx);
 764 }
 765
 766
 767 static Handle<SharedFunctionInfo> CompileToplevel(CompilationInfo* info) {
 768   Isolate* isolate = info->isolate();
 769   PostponeInterruptsScope postpone(isolate);
 770   ASSERT(!isolate->native_context().is_null());
 771   Handle<Script> script = info->script();
 772
 773   // TODO(svenpanne) Obscure place for this, perhaps move to OnBeforeCompile?
 774   FixedArray* array = isolate->native_context()->embedder_data();
 775   script->set_context_data(array->get(0));
 776
 777   isolate->debug()->OnBeforeCompile(script);
 778
 779   ASSERT(info->is_eval() || info->is_global());
 780
 781   bool parse_allow_lazy =
 782       (info->cached_data_mode() == CONSUME_CACHED_DATA ||
 783        String::cast(script->source())->length() > FLAG_min_preparse_length) &&
 784       !DebuggerWantsEagerCompilation(info);
 785
 786   if (!parse_allow_lazy && info->cached_data_mode() != NO_CACHED_DATA) {
 787     // We are going to parse eagerly, but we either 1) have cached data produced
 788     // by lazy parsing or 2) are asked to generate cached data. We cannot use
 789     // the existing data, since it won't contain all the symbols we need for
 790     // eager parsing. In addition, it doesn't make sense to produce the data
 791     // when parsing eagerly. That data would contain all symbols, but no
 792     // functions, so it cannot be used to aid lazy parsing later.
 793     info->SetCachedData(NULL, NO_CACHED_DATA);
 794   }
 795
 796   Handle<SharedFunctionInfo> result;
 797
 798   { VMState<COMPILER> state(info->isolate());
 799     if (!Parser::Parse(info, parse_allow_lazy)) {
 800       return Handle<SharedFunctionInfo>::null();
 801     }
 802
 803     FunctionLiteral* lit = info->function();
 804     LiveEditFunctionTracker live_edit_tracker(isolate, lit);
 805
 806     // Measure how long it takes to do the compilation; only take the
 807     // rest of the function into account to avoid overlap with the
 808     // parsing statistics.
 809     HistogramTimer* rate = info->is_eval()
 810           ? info->isolate()->counters()->compile_eval()
 811           : info->isolate()->counters()->compile();
 812     HistogramTimerScope timer(rate);
 813
 814     // Compile the code.
 815     if (!CompileUnoptimizedCode(info)) {
 816       return Handle<SharedFunctionInfo>::null();
 817     }
 818
 819     // Allocate function.
 820     ASSERT(!info->code().is_null());
 821     result = isolate->factory()->NewSharedFunctionInfo(
 822         lit->name(),
 823         lit->materialized_literal_count(),
 824         lit->is_generator(),
 825         info->code(),
 826         ScopeInfo::Create(info->scope(), info->zone()),
 827         info->feedback_vector());
 828
 829     ASSERT_EQ(RelocInfo::kNoPosition, lit->function_token_position());
 830     SetFunctionInfo(result, lit, true, script);
 831
 832     Handle<String> script_name = script->name()->IsString()
 833         ? Handle<String>(String::cast(script->name()))
 834         : isolate->factory()->empty_string();
 835     Logger::LogEventsAndTags log_tag = info->is_eval()
 836         ? Logger::EVAL_TAG
 837         : Logger::ToNativeByScript(Logger::SCRIPT_TAG, *script);
 838
 839     PROFILE(isolate, CodeCreateEvent(
 840                 log_tag, *info->code(), *result, info, *script_name));
 841     GDBJIT(AddCode(script_name, script, info->code(), info));
 842
 843     // Hint to the runtime system used when allocating space for initial
 844     // property space by setting the expected number of properties for
 845     // the instances of the function.
 846     SetExpectedNofPropertiesFromEstimate(result,
 847                                          lit->expected_property_count());
 848
 849     script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
 850
 851     live_edit_tracker.RecordFunctionInfo(result, lit, info->zone());
 852   }
 853
 854   isolate->debug()->OnAfterCompile(script, Debug::NO_AFTER_COMPILE_FLAGS);
 855
 856   return result;
 857 }
 858
 859
 860 MaybeHandle<JSFunction> Compiler::GetFunctionFromEval(
 861     Handle<String> source,
 862     Handle<Context> context,
 863     StrictMode strict_mode,
 864     ParseRestriction restriction,
 865     int scope_position) {
 866   Isolate* isolate = source->GetIsolate();
 867   int source_length = source->length();
 868   isolate->counters()->total_eval_size()->Increment(source_length);
 869   isolate->counters()->total_compile_size()->Increment(source_length);
 870
 871   CompilationCache* compilation_cache = isolate->compilation_cache();
 872   MaybeHandle<SharedFunctionInfo> maybe_shared_info =
 873       compilation_cache->LookupEval(source, context, strict_mode,
 874                                     scope_position);
 875   Handle<SharedFunctionInfo> shared_info;
 876
 877   if (!maybe_shared_info.ToHandle(&shared_info)) {
 878     Handle<Script> script = isolate->factory()->NewScript(source);
 879     CompilationInfoWithZone info(script);
 880     info.MarkAsEval();
 881     if (context->IsNativeContext()) info.MarkAsGlobal();
 882     info.SetStrictMode(strict_mode);
 883     info.SetParseRestriction(restriction);
 884     info.SetContext(context);
 885
 886     Debug::RecordEvalCaller(script);
 887
 888     shared_info = CompileToplevel(&info);
 889
 890     if (shared_info.is_null()) {
 891       return MaybeHandle<JSFunction>();
 892     } else {
 893       // Explicitly disable optimization for eval code. We're not yet prepared
 894       // to handle eval-code in the optimizing compiler.
 895       shared_info->DisableOptimization(kEval);
 896
 897       // If caller is strict mode, the result must be in strict mode as well.
 898       ASSERT(strict_mode == SLOPPY || shared_info->strict_mode() == STRICT);
 899       if (!shared_info->dont_cache()) {
 900         compilation_cache->PutEval(
 901             source, context, shared_info, scope_position);
 902       }
 903     }
 904   } else if (shared_info->ic_age() != isolate->heap()->global_ic_age()) {
 905     shared_info->ResetForNewContext(isolate->heap()->global_ic_age());
 906   }
 907
 908   return isolate->factory()->NewFunctionFromSharedFunctionInfo(
 909       shared_info, context, NOT_TENURED);
 910 }
 911
 912
 913 Handle<SharedFunctionInfo> Compiler::CompileScript(
 914     Handle<String> source,
 915     Handle<Object> script_name,
 916     int line_offset,
 917     int column_offset,
 918     bool is_shared_cross_origin,
 919     Handle<Context> context,
 920     v8::Extension* extension,
 921     ScriptData** cached_data,
 922     CachedDataMode cached_data_mode,
 923     NativesFlag natives) {
 924   if (cached_data_mode == NO_CACHED_DATA) {
 925     cached_data = NULL;
 926   } else if (cached_data_mode == PRODUCE_CACHED_DATA) {
 927     ASSERT(cached_data && !*cached_data);
 928   } else {
 929     ASSERT(cached_data_mode == CONSUME_CACHED_DATA);
 930     ASSERT(cached_data && *cached_data);
 931   }
 932   Isolate* isolate = source->GetIsolate();
 933   int source_length = source->length();
 934   isolate->counters()->total_load_size()->Increment(source_length);
 935   isolate->counters()->total_compile_size()->Increment(source_length);
 936
 937   CompilationCache* compilation_cache = isolate->compilation_cache();
 938
 939   // Do a lookup in the compilation cache but not for extensions.
 940   MaybeHandle<SharedFunctionInfo> maybe_result;
 941   Handle<SharedFunctionInfo> result;
 942   if (extension == NULL) {
 943     maybe_result = compilation_cache->LookupScript(
 944         source, script_name, line_offset, column_offset,
 945         is_shared_cross_origin, context);
 946   }
 947
 948   if (!maybe_result.ToHandle(&result)) {
 949     // No cache entry found. Compile the script.
 950
 951     // Create a script object describing the script to be compiled.
 952     Handle<Script> script = isolate->factory()->NewScript(source);
 953     if (natives == NATIVES_CODE) {
 954       script->set_type(Smi::FromInt(Script::TYPE_NATIVE));
 955     }
 956     if (!script_name.is_null()) {
 957       script->set_name(*script_name);
 958       script->set_line_offset(Smi::FromInt(line_offset));
 959       script->set_column_offset(Smi::FromInt(column_offset));
 960     }
 961     script->set_is_shared_cross_origin(is_shared_cross_origin);
 962
 963     // Compile the function and add it to the cache.
 964     CompilationInfoWithZone info(script);
 965     info.MarkAsGlobal();
 966     info.SetExtension(extension);
 967     info.SetCachedData(cached_data, cached_data_mode);
 968     info.SetContext(context);
 969     if (FLAG_use_strict) info.SetStrictMode(STRICT);
 970     result = CompileToplevel(&info);
 971     if (extension == NULL && !result.is_null() && !result->dont_cache()) {
 972       compilation_cache->PutScript(source, context, result);
 973     }
 974     if (result.is_null()) isolate->ReportPendingMessages();
 975   } else if (result->ic_age() != isolate->heap()->global_ic_age()) {
 976       result->ResetForNewContext(isolate->heap()->global_ic_age());
 977   }
 978   return result;
 979 }
 980
 981
 982 Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(FunctionLiteral* literal,
 983                                                        Handle<Script> script) {
 984   // Precondition: code has been parsed and scopes have been analyzed.
 985   CompilationInfoWithZone info(script);
 986   info.SetFunction(literal);
 987   info.PrepareForCompilation(literal->scope());
 988   info.SetStrictMode(literal->scope()->strict_mode());
 989
 990   Isolate* isolate = info.isolate();
 991   Factory* factory = isolate->factory();
 992   LiveEditFunctionTracker live_edit_tracker(isolate, literal);
 993   // Determine if the function can be lazily compiled. This is necessary to
 994   // allow some of our builtin JS files to be lazily compiled. These
 995   // builtins cannot be handled lazily by the parser, since we have to know
 996   // if a function uses the special natives syntax, which is something the
 997   // parser records.
 998   // If the debugger requests compilation for break points, we cannot be
 999   // aggressive about lazy compilation, because it might trigger compilation
1000   // of functions without an outer context when setting a breakpoint through
1001   // Debug::FindSharedFunctionInfoInScript.
1002   bool allow_lazy_without_ctx = literal->AllowsLazyCompilationWithoutContext();
1003   bool allow_lazy = literal->AllowsLazyCompilation() &&
1004       !DebuggerWantsEagerCompilation(&info, allow_lazy_without_ctx);
1005
1006   // Generate code
1007   Handle<ScopeInfo> scope_info;
1008   if (FLAG_lazy && allow_lazy && !literal->is_parenthesized()) {
1009     Handle<Code> code = isolate->builtins()->CompileUnoptimized();
1010     info.SetCode(code);
1011     scope_info = Handle<ScopeInfo>(ScopeInfo::Empty(isolate));
1012   } else if (FullCodeGenerator::MakeCode(&info)) {
1013     ASSERT(!info.code().is_null());
1014     scope_info = ScopeInfo::Create(info.scope(), info.zone());
1015   } else {
1016     return Handle<SharedFunctionInfo>::null();
1017   }
1018
1019   // Create a shared function info object.
1020   Handle<SharedFunctionInfo> result =
1021       factory->NewSharedFunctionInfo(literal->name(),
1022                                      literal->materialized_literal_count(),
1023                                      literal->is_generator(),
1024                                      info.code(),
1025                                      scope_info,
1026                                      info.feedback_vector());
1027   SetFunctionInfo(result, literal, false, script);
1028   RecordFunctionCompilation(Logger::FUNCTION_TAG, &info, result);
1029   result->set_allows_lazy_compilation(allow_lazy);
1030   result->set_allows_lazy_compilation_without_context(allow_lazy_without_ctx);
1031
1032   // Set the expected number of properties for instances and return
1033   // the resulting function.
1034   SetExpectedNofPropertiesFromEstimate(result,
1035                                        literal->expected_property_count());
1036   live_edit_tracker.RecordFunctionInfo(result, literal, info.zone());
1037   return result;
1038 }
1039
1040
1041 MUST_USE_RESULT static MaybeHandle<Code> GetCodeFromOptimizedCodeMap(
1042     Handle<JSFunction> function,
1043     BailoutId osr_ast_id) {
1044   if (FLAG_cache_optimized_code) {
1045     Handle<SharedFunctionInfo> shared(function->shared());
1046     DisallowHeapAllocation no_gc;
1047     int index = shared->SearchOptimizedCodeMap(
1048         function->context()->native_context(), osr_ast_id);
1049     if (index > 0) {
1050       if (FLAG_trace_opt) {
1051         PrintF("[found optimized code for ");
1052         function->ShortPrint();
1053         if (!osr_ast_id.IsNone()) {
1054           PrintF(" at OSR AST id %d", osr_ast_id.ToInt());
1055         }
1056         PrintF("]\n");
1057       }
1058       FixedArray* literals = shared->GetLiteralsFromOptimizedCodeMap(index);
1059       if (literals != NULL) function->set_literals(literals);
1060       return Handle<Code>(shared->GetCodeFromOptimizedCodeMap(index));
1061     }
1062   }
1063   return MaybeHandle<Code>();
1064 }
1065
1066
1067 static void InsertCodeIntoOptimizedCodeMap(CompilationInfo* info) {
1068   Handle<Code> code = info->code();
1069   if (code->kind() != Code::OPTIMIZED_FUNCTION) return;  // Nothing to do.
1070
1071   // Cache optimized code.
1072   if (FLAG_cache_optimized_code) {
1073     Handle<JSFunction> function = info->closure();
1074     Handle<SharedFunctionInfo> shared(function->shared());
1075     Handle<FixedArray> literals(function->literals());
1076     Handle<Context> native_context(function->context()->native_context());
1077     SharedFunctionInfo::AddToOptimizedCodeMap(
1078         shared, native_context, code, literals, info->osr_ast_id());
1079   }
1080 }
1081
1082
1083 static bool CompileOptimizedPrologue(CompilationInfo* info) {
1084   if (!Parser::Parse(info)) return false;
1085   info->SetStrictMode(info->function()->strict_mode());
1086
1087   if (!Rewriter::Rewrite(info)) return false;
1088   if (!Scope::Analyze(info)) return false;
1089   ASSERT(info->scope() != NULL);
1090   return true;
1091 }
1092
1093
1094 static bool GetOptimizedCodeNow(CompilationInfo* info) {
1095   if (!CompileOptimizedPrologue(info)) return false;
1096
1097   Logger::TimerEventScope timer(
1098       info->isolate(), Logger::TimerEventScope::v8_recompile_synchronous);
1099
1100   OptimizedCompileJob job(info);
1101   if (job.CreateGraph() != OptimizedCompileJob::SUCCEEDED) return false;
1102   if (job.OptimizeGraph() != OptimizedCompileJob::SUCCEEDED) return false;
1103   if (job.GenerateCode() != OptimizedCompileJob::SUCCEEDED) return false;
1104
1105   // Success!
1106   ASSERT(!info->isolate()->has_pending_exception());
1107   InsertCodeIntoOptimizedCodeMap(info);
1108   Compiler::RecordFunctionCompilation(
1109       Logger::LAZY_COMPILE_TAG, info, info->shared_info());
1110   return true;
1111 }
1112
1113
1114 static bool GetOptimizedCodeLater(CompilationInfo* info) {
1115   Isolate* isolate = info->isolate();
1116   if (!isolate->optimizing_compiler_thread()->IsQueueAvailable()) {
1117     if (FLAG_trace_concurrent_recompilation) {
1118       PrintF("  ** Compilation queue full, will retry optimizing ");
1119       info->closure()->PrintName();
1120       PrintF(" later.\n");
1121     }
1122     return false;
1123   }
1124
1125   CompilationHandleScope handle_scope(info);
1126   if (!CompileOptimizedPrologue(info)) return false;
1127   info->SaveHandles();  // Copy handles to the compilation handle scope.
1128
1129   Logger::TimerEventScope timer(
1130       isolate, Logger::TimerEventScope::v8_recompile_synchronous);
1131
1132   OptimizedCompileJob* job = new(info->zone()) OptimizedCompileJob(info);
1133   OptimizedCompileJob::Status status = job->CreateGraph();
1134   if (status != OptimizedCompileJob::SUCCEEDED) return false;
1135   isolate->optimizing_compiler_thread()->QueueForOptimization(job);
1136
1137   if (FLAG_trace_concurrent_recompilation) {
1138     PrintF("  ** Queued ");
1139      info->closure()->PrintName();
1140     if (info->is_osr()) {
1141       PrintF(" for concurrent OSR at %d.\n", info->osr_ast_id().ToInt());
1142     } else {
1143       PrintF(" for concurrent optimization.\n");
1144     }
1145   }
1146   return true;
1147 }
1148
1149
1150 MaybeHandle<Code> Compiler::GetOptimizedCode(Handle<JSFunction> function,
1151                                              Handle<Code> current_code,
1152                                              ConcurrencyMode mode,
1153                                              BailoutId osr_ast_id) {
1154   Handle<Code> cached_code;
1155   if (GetCodeFromOptimizedCodeMap(
1156           function, osr_ast_id).ToHandle(&cached_code)) {
1157     return cached_code;
1158   }
1159
1160   SmartPointer<CompilationInfo> info(new CompilationInfoWithZone(function));
1161   Isolate* isolate = info->isolate();
1162   VMState<COMPILER> state(isolate);
1163   ASSERT(!isolate->has_pending_exception());
1164   PostponeInterruptsScope postpone(isolate);
1165
1166   Handle<SharedFunctionInfo> shared = info->shared_info();
1167   ASSERT_NE(ScopeInfo::Empty(isolate), shared->scope_info());
1168   int compiled_size = shared->end_position() - shared->start_position();
1169   isolate->counters()->total_compile_size()->Increment(compiled_size);
1170   current_code->set_profiler_ticks(0);
1171
1172   info->SetOptimizing(osr_ast_id, current_code);
1173
1174   if (mode == CONCURRENT) {
1175     if (GetOptimizedCodeLater(info.get())) {
1176       info.Detach();  // The background recompile job owns this now.
1177       return isolate->builtins()->InOptimizationQueue();
1178     }
1179   } else {
1180     if (GetOptimizedCodeNow(info.get())) return info->code();
1181   }
1182
1183   // Failed.
1184   if (FLAG_trace_opt) {
1185     PrintF("[failed to optimize ");
1186     function->PrintName();
1187     PrintF(": %s]\n", GetBailoutReason(info->bailout_reason()));
1188   }
1189
1190   if (isolate->has_pending_exception()) isolate->clear_pending_exception();
1191   return MaybeHandle<Code>();
1192 }
1193
1194
1195 Handle<Code> Compiler::GetConcurrentlyOptimizedCode(OptimizedCompileJob* job) {
1196   // Take ownership of compilation info.  Deleting compilation info
1197   // also tears down the zone and the recompile job.
1198   SmartPointer<CompilationInfo> info(job->info());
1199   Isolate* isolate = info->isolate();
1200
1201   VMState<COMPILER> state(isolate);
1202   Logger::TimerEventScope timer(
1203       isolate, Logger::TimerEventScope::v8_recompile_synchronous);
1204
1205   Handle<SharedFunctionInfo> shared = info->shared_info();
1206   shared->code()->set_profiler_ticks(0);
1207
1208   // 1) Optimization may have failed.
1209   // 2) The function may have already been optimized by OSR.  Simply continue.
1210   //    Except when OSR already disabled optimization for some reason.
1211   // 3) The code may have already been invalidated due to dependency change.
1212   // 4) Debugger may have been activated.
1213
1214   if (job->last_status() != OptimizedCompileJob::SUCCEEDED ||
1215       shared->optimization_disabled() ||
1216       info->HasAbortedDueToDependencyChange() ||
1217       isolate->DebuggerHasBreakPoints()) {
1218     return Handle<Code>::null();
1219   }
1220
1221   if (job->GenerateCode() != OptimizedCompileJob::SUCCEEDED) {
1222     return Handle<Code>::null();
1223   }
1224
1225   Compiler::RecordFunctionCompilation(
1226       Logger::LAZY_COMPILE_TAG, info.get(), shared);
1227   if (info->shared_info()->SearchOptimizedCodeMap(
1228           info->context()->native_context(), info->osr_ast_id()) == -1) {
1229     InsertCodeIntoOptimizedCodeMap(info.get());
1230   }
1231
1232   if (FLAG_trace_concurrent_recompilation) {
1233     PrintF("  ** Optimized code for ");
1234     info->closure()->PrintName();
1235     PrintF(" generated.\n");
1236   }
1237
1238   return Handle<Code>(*info->code());
1239 }
1240
1241
1242 void Compiler::RecordFunctionCompilation(Logger::LogEventsAndTags tag,
1243                                          CompilationInfo* info,
1244                                          Handle<SharedFunctionInfo> shared) {
1245   // SharedFunctionInfo is passed separately, because if CompilationInfo
1246   // was created using Script object, it will not have it.
1247
1248   // Log the code generation. If source information is available include
1249   // script name and line number. Check explicitly whether logging is
1250   // enabled as finding the line number is not free.
1251   if (info->isolate()->logger()->is_logging_code_events() ||
1252       info->isolate()->cpu_profiler()->is_profiling()) {
1253     Handle<Script> script = info->script();
1254     Handle<Code> code = info->code();
1255     if (code.is_identical_to(
1256             info->isolate()->builtins()->CompileUnoptimized())) {
1257       return;
1258     }
1259     int line_num = Script::GetLineNumber(script, shared->start_position()) + 1;
1260     int column_num =
1261         Script::GetColumnNumber(script, shared->start_position()) + 1;
1262     String* script_name = script->name()->IsString()
1263         ? String::cast(script->name())
1264         : info->isolate()->heap()->empty_string();
1265     Logger::LogEventsAndTags log_tag = Logger::ToNativeByScript(tag, *script);
1266     PROFILE(info->isolate(), CodeCreateEvent(
1267         log_tag, *code, *shared, info, script_name, line_num, column_num));
1268   }
1269
1270   GDBJIT(AddCode(Handle<String>(shared->DebugName()),
1271                  Handle<Script>(info->script()),
1272                  Handle<Code>(info->code()),
1273                  info));
1274 }
1275
1276
1277 CompilationPhase::CompilationPhase(const char* name, CompilationInfo* info)
1278     : name_(name), info_(info), zone_(info->isolate()) {
1279   if (FLAG_hydrogen_stats) {
1280     info_zone_start_allocation_size_ = info->zone()->allocation_size();
1281     timer_.Start();
1282   }
1283 }
1284
1285
1286 CompilationPhase::~CompilationPhase() {
1287   if (FLAG_hydrogen_stats) {
1288     unsigned size = zone()->allocation_size();
1289     size += info_->zone()->allocation_size() - info_zone_start_allocation_size_;
1290     isolate()->GetHStatistics()->SaveTiming(name_, timer_.Elapsed(), size);
1291   }
1292 }
1293
1294
1295 bool CompilationPhase::ShouldProduceTraceOutput() const {
1296   // Trace if the appropriate trace flag is set and the phase name's first
1297   // character is in the FLAG_trace_phase command line parameter.
1298   AllowHandleDereference allow_deref;
1299   bool tracing_on = info()->IsStub()
1300       ? FLAG_trace_hydrogen_stubs
1301       : (FLAG_trace_hydrogen &&
1302          info()->closure()->PassesFilter(FLAG_trace_hydrogen_filter));
1303   return (tracing_on &&
1304       OS::StrChr(const_cast<char*>(FLAG_trace_phase), name_[0]) != NULL);
1305 }
1306
1307 } }  // namespace v8::internal