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 "v8.h"
   6
   7 #include "compiler.h"
   8
   9 #include "bootstrapper.h"
  10 #include "codegen.h"
  11 #include "compilation-cache.h"
  12 #include "cpu-profiler.h"
  13 #include "debug.h"
  14 #include "deoptimizer.h"
  15 #include "full-codegen.h"
  16 #include "gdb-jit.h"
  17 #include "typing.h"
  18 #include "hydrogen.h"
  19 #include "isolate-inl.h"
  20 #include "lithium.h"
  21 #include "liveedit.h"
  22 #include "parser.h"
  23 #include "rewriter.h"
  24 #include "runtime-profiler.h"
  25 #include "scanner-character-streams.h"
  26 #include "scopeinfo.h"
  27 #include "scopes.h"
  28 #include "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) {
 114     MarkAsNative();
 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 // Determine whether to use the full compiler for all code. If the flag
 283 // --always-full-compiler is specified this is the case. For the virtual frame
 284 // based compiler the full compiler is also used if a debugger is connected, as
 285 // the code from the full compiler supports mode precise break points. For the
 286 // crankshaft adaptive compiler debugging the optimized code is not possible at
 287 // all. However crankshaft support recompilation of functions, so in this case
 288 // the full compiler need not be be used if a debugger is attached, but only if
 289 // break points has actually been set.
 290 static bool IsDebuggerActive(Isolate* isolate) {
 291   return isolate->use_crankshaft() ?
 292     isolate->debug()->has_break_points() :
 293     isolate->debugger()->IsDebuggerActive();
 294 }
 295
 296
 297 OptimizedCompileJob::Status OptimizedCompileJob::CreateGraph() {
 298   ASSERT(isolate()->use_crankshaft());
 299   ASSERT(info()->IsOptimizing());
 300   ASSERT(!info()->IsCompilingForDebugging());
 301
 302   // We should never arrive here if there is no code object on the
 303   // shared function object.
 304   ASSERT(info()->shared_info()->code()->kind() == Code::FUNCTION);
 305
 306   // We should never arrive here if optimization has been disabled on the
 307   // shared function info.
 308   ASSERT(!info()->shared_info()->optimization_disabled());
 309
 310   // Fall back to using the full code generator if it's not possible
 311   // to use the Hydrogen-based optimizing compiler. We already have
 312   // generated code for this from the shared function object.
 313   if (FLAG_always_full_compiler) return AbortOptimization();
 314   if (IsDebuggerActive(isolate())) return AbortOptimization(kDebuggerIsActive);
 315
 316   // Limit the number of times we re-compile a functions with
 317   // the optimizing compiler.
 318   const int kMaxOptCount =
 319       FLAG_deopt_every_n_times == 0 ? FLAG_max_opt_count : 1000;
 320   if (info()->opt_count() > kMaxOptCount) {
 321     return AbortAndDisableOptimization(kOptimizedTooManyTimes);
 322   }
 323
 324   // Due to an encoding limit on LUnallocated operands in the Lithium
 325   // language, we cannot optimize functions with too many formal parameters
 326   // or perform on-stack replacement for function with too many
 327   // stack-allocated local variables.
 328   //
 329   // The encoding is as a signed value, with parameters and receiver using
 330   // the negative indices and locals the non-negative ones.
 331   const int parameter_limit = -LUnallocated::kMinFixedSlotIndex;
 332   Scope* scope = info()->scope();
 333   if ((scope->num_parameters() + 1) > parameter_limit) {
 334     return AbortAndDisableOptimization(kTooManyParameters);
 335   }
 336
 337   const int locals_limit = LUnallocated::kMaxFixedSlotIndex;
 338   if (info()->is_osr() &&
 339       scope->num_parameters() + 1 + scope->num_stack_slots() > locals_limit) {
 340     return AbortAndDisableOptimization(kTooManyParametersLocals);
 341   }
 342
 343   if (scope->HasIllegalRedeclaration()) {
 344     return AbortAndDisableOptimization(kFunctionWithIllegalRedeclaration);
 345   }
 346
 347   // Take --hydrogen-filter into account.
 348   if (!info()->closure()->PassesFilter(FLAG_hydrogen_filter)) {
 349     return AbortOptimization(kHydrogenFilter);
 350   }
 351
 352   // Recompile the unoptimized version of the code if the current version
 353   // doesn't have deoptimization support. Alternatively, we may decide to
 354   // run the full code generator to get a baseline for the compile-time
 355   // performance of the hydrogen-based compiler.
 356   bool should_recompile = !info()->shared_info()->has_deoptimization_support();
 357   if (should_recompile || FLAG_hydrogen_stats) {
 358     ElapsedTimer timer;
 359     if (FLAG_hydrogen_stats) {
 360       timer.Start();
 361     }
 362     CompilationInfoWithZone unoptimized(info()->shared_info());
 363     // Note that we use the same AST that we will use for generating the
 364     // optimized code.
 365     unoptimized.SetFunction(info()->function());
 366     unoptimized.PrepareForCompilation(info()->scope());
 367     unoptimized.SetContext(info()->context());
 368     if (should_recompile) unoptimized.EnableDeoptimizationSupport();
 369     bool succeeded = FullCodeGenerator::MakeCode(&unoptimized);
 370     if (should_recompile) {
 371       if (!succeeded) return SetLastStatus(FAILED);
 372       Handle<SharedFunctionInfo> shared = info()->shared_info();
 373       shared->EnableDeoptimizationSupport(*unoptimized.code());
 374       // The existing unoptimized code was replaced with the new one.
 375       Compiler::RecordFunctionCompilation(
 376           Logger::LAZY_COMPILE_TAG, &unoptimized, shared);
 377     }
 378     if (FLAG_hydrogen_stats) {
 379       isolate()->GetHStatistics()->IncrementFullCodeGen(timer.Elapsed());
 380     }
 381   }
 382
 383   // Check that the unoptimized, shared code is ready for
 384   // optimizations.  When using the always_opt flag we disregard the
 385   // optimizable marker in the code object and optimize anyway. This
 386   // is safe as long as the unoptimized code has deoptimization
 387   // support.
 388   ASSERT(FLAG_always_opt || info()->shared_info()->code()->optimizable());
 389   ASSERT(info()->shared_info()->has_deoptimization_support());
 390
 391   if (FLAG_trace_hydrogen) {
 392     Handle<String> name = info()->function()->debug_name();
 393     PrintF("-----------------------------------------------------------\n");
 394     PrintF("Compiling method %s using hydrogen\n", name->ToCString().get());
 395     isolate()->GetHTracer()->TraceCompilation(info());
 396   }
 397
 398   // Type-check the function.
 399   AstTyper::Run(info());
 400
 401   graph_builder_ = FLAG_hydrogen_track_positions
 402       ? new(info()->zone()) HOptimizedGraphBuilderWithPositions(info())
 403       : new(info()->zone()) HOptimizedGraphBuilder(info());
 404
 405   Timer t(this, &time_taken_to_create_graph_);
 406   info()->set_this_has_uses(false);
 407   graph_ = graph_builder_->CreateGraph();
 408
 409   if (isolate()->has_pending_exception()) {
 410     return SetLastStatus(FAILED);
 411   }
 412
 413   // The function being compiled may have bailed out due to an inline
 414   // candidate bailing out.  In such a case, we don't disable
 415   // optimization on the shared_info.
 416   ASSERT(!graph_builder_->inline_bailout() || graph_ == NULL);
 417   if (graph_ == NULL) {
 418     if (graph_builder_->inline_bailout()) {
 419       return AbortOptimization();
 420     } else {
 421       return AbortAndDisableOptimization();
 422     }
 423   }
 424
 425   if (info()->HasAbortedDueToDependencyChange()) {
 426     return AbortOptimization(kBailedOutDueToDependencyChange);
 427   }
 428
 429   return SetLastStatus(SUCCEEDED);
 430 }
 431
 432
 433 OptimizedCompileJob::Status OptimizedCompileJob::OptimizeGraph() {
 434   DisallowHeapAllocation no_allocation;
 435   DisallowHandleAllocation no_handles;
 436   DisallowHandleDereference no_deref;
 437   DisallowCodeDependencyChange no_dependency_change;
 438
 439   ASSERT(last_status() == SUCCEEDED);
 440   Timer t(this, &time_taken_to_optimize_);
 441   ASSERT(graph_ != NULL);
 442   BailoutReason bailout_reason = kNoReason;
 443
 444   if (graph_->Optimize(&bailout_reason)) {
 445     chunk_ = LChunk::NewChunk(graph_);
 446     if (chunk_ != NULL) return SetLastStatus(SUCCEEDED);
 447   } else if (bailout_reason != kNoReason) {
 448     graph_builder_->Bailout(bailout_reason);
 449   }
 450
 451   return AbortOptimization();
 452 }
 453
 454
 455 OptimizedCompileJob::Status OptimizedCompileJob::GenerateCode() {
 456   ASSERT(last_status() == SUCCEEDED);
 457   ASSERT(!info()->HasAbortedDueToDependencyChange());
 458   DisallowCodeDependencyChange no_dependency_change;
 459   {  // Scope for timer.
 460     Timer timer(this, &time_taken_to_codegen_);
 461     ASSERT(chunk_ != NULL);
 462     ASSERT(graph_ != NULL);
 463     // Deferred handles reference objects that were accessible during
 464     // graph creation.  To make sure that we don't encounter inconsistencies
 465     // between graph creation and code generation, we disallow accessing
 466     // objects through deferred handles during the latter, with exceptions.
 467     DisallowDeferredHandleDereference no_deferred_handle_deref;
 468     Handle<Code> optimized_code = chunk_->Codegen();
 469     if (optimized_code.is_null()) {
 470       if (info()->bailout_reason() == kNoReason) {
 471         info_->set_bailout_reason(kCodeGenerationFailed);
 472       }
 473       return AbortAndDisableOptimization();
 474     }
 475     info()->SetCode(optimized_code);
 476   }
 477   RecordOptimizationStats();
 478   // Add to the weak list of optimized code objects.
 479   info()->context()->native_context()->AddOptimizedCode(*info()->code());
 480   return SetLastStatus(SUCCEEDED);
 481 }
 482
 483
 484 void OptimizedCompileJob::RecordOptimizationStats() {
 485   Handle<JSFunction> function = info()->closure();
 486   if (!function->IsOptimized()) {
 487     // Concurrent recompilation and OSR may race.  Increment only once.
 488     int opt_count = function->shared()->opt_count();
 489     function->shared()->set_opt_count(opt_count + 1);
 490   }
 491   double ms_creategraph = time_taken_to_create_graph_.InMillisecondsF();
 492   double ms_optimize = time_taken_to_optimize_.InMillisecondsF();
 493   double ms_codegen = time_taken_to_codegen_.InMillisecondsF();
 494   if (FLAG_trace_opt) {
 495     PrintF("[optimizing ");
 496     function->ShortPrint();
 497     PrintF(" - took %0.3f, %0.3f, %0.3f ms]\n", ms_creategraph, ms_optimize,
 498            ms_codegen);
 499   }
 500   if (FLAG_trace_opt_stats) {
 501     static double compilation_time = 0.0;
 502     static int compiled_functions = 0;
 503     static int code_size = 0;
 504
 505     compilation_time += (ms_creategraph + ms_optimize + ms_codegen);
 506     compiled_functions++;
 507     code_size += function->shared()->SourceSize();
 508     PrintF("Compiled: %d functions with %d byte source size in %fms.\n",
 509            compiled_functions,
 510            code_size,
 511            compilation_time);
 512   }
 513   if (FLAG_hydrogen_stats) {
 514     isolate()->GetHStatistics()->IncrementSubtotals(time_taken_to_create_graph_,
 515                                                     time_taken_to_optimize_,
 516                                                     time_taken_to_codegen_);
 517   }
 518 }
 519
 520
 521 // Sets the expected number of properties based on estimate from compiler.
 522 void SetExpectedNofPropertiesFromEstimate(Handle<SharedFunctionInfo> shared,
 523                                           int estimate) {
 524   // See the comment in SetExpectedNofProperties.
 525   if (shared->live_objects_may_exist()) return;
 526
 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 (Serializer::enabled(shared->GetIsolate())) {
 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   ASSERT(!isolate->has_pending_exception());
 715   Handle<Code> old_code(function->shared()->code());
 716   ASSERT(old_code->kind() == Code::FUNCTION);
 717   ASSERT(!old_code->has_debug_break_slots());
 718
 719   info.MarkCompilingForDebugging();
 720   if (old_code->is_compiled_optimizable()) {
 721     info.EnableDeoptimizationSupport();
 722   } else {
 723     info.MarkNonOptimizable();
 724   }
 725   MaybeHandle<Code> maybe_new_code = GetUnoptimizedCodeCommon(&info);
 726   Handle<Code> new_code;
 727   if (!maybe_new_code.ToHandle(&new_code)) {
 728     isolate->clear_pending_exception();
 729   } else {
 730     ASSERT_EQ(old_code->is_compiled_optimizable(),
 731               new_code->is_compiled_optimizable());
 732   }
 733   return maybe_new_code;
 734 }
 735
 736
 737 void Compiler::CompileForLiveEdit(Handle<Script> script) {
 738   // TODO(635): support extensions.
 739   CompilationInfoWithZone info(script);
 740   PostponeInterruptsScope postpone(info.isolate());
 741   VMState<COMPILER> state(info.isolate());
 742
 743   info.MarkAsGlobal();
 744   if (!Parser::Parse(&info)) return;
 745   info.SetStrictMode(info.function()->strict_mode());
 746
 747   LiveEditFunctionTracker tracker(info.isolate(), info.function());
 748   if (!CompileUnoptimizedCode(&info)) return;
 749   if (!info.shared_info().is_null()) {
 750     Handle<ScopeInfo> scope_info = ScopeInfo::Create(info.scope(),
 751                                                      info.zone());
 752     info.shared_info()->set_scope_info(*scope_info);
 753   }
 754   tracker.RecordRootFunctionInfo(info.code());
 755 }
 756
 757
 758 static bool DebuggerWantsEagerCompilation(CompilationInfo* info,
 759                                           bool allow_lazy_without_ctx = false) {
 760   return LiveEditFunctionTracker::IsActive(info->isolate()) ||
 761          (info->isolate()->DebuggerHasBreakPoints() && !allow_lazy_without_ctx);
 762 }
 763
 764
 765 static Handle<SharedFunctionInfo> CompileToplevel(CompilationInfo* info) {
 766   Isolate* isolate = info->isolate();
 767   PostponeInterruptsScope postpone(isolate);
 768   ASSERT(!isolate->native_context().is_null());
 769   Handle<Script> script = info->script();
 770
 771   // TODO(svenpanne) Obscure place for this, perhaps move to OnBeforeCompile?
 772   FixedArray* array = isolate->native_context()->embedder_data();
 773   script->set_context_data(array->get(0));
 774
 775   isolate->debugger()->OnBeforeCompile(script);
 776
 777   ASSERT(info->is_eval() || info->is_global());
 778
 779   bool parse_allow_lazy =
 780       (info->cached_data_mode() == CONSUME_CACHED_DATA ||
 781        String::cast(script->source())->length() > FLAG_min_preparse_length) &&
 782       !DebuggerWantsEagerCompilation(info);
 783
 784   if (!parse_allow_lazy && info->cached_data_mode() != NO_CACHED_DATA) {
 785     // We are going to parse eagerly, but we either 1) have cached data produced
 786     // by lazy parsing or 2) are asked to generate cached data. We cannot use
 787     // the existing data, since it won't contain all the symbols we need for
 788     // eager parsing. In addition, it doesn't make sense to produce the data
 789     // when parsing eagerly. That data would contain all symbols, but no
 790     // functions, so it cannot be used to aid lazy parsing later.
 791     info->SetCachedData(NULL, NO_CACHED_DATA);
 792   }
 793
 794   Handle<SharedFunctionInfo> result;
 795
 796   { VMState<COMPILER> state(info->isolate());
 797     if (!Parser::Parse(info, parse_allow_lazy)) {
 798       return Handle<SharedFunctionInfo>::null();
 799     }
 800
 801     FunctionLiteral* lit = info->function();
 802     LiveEditFunctionTracker live_edit_tracker(isolate, lit);
 803
 804     // Measure how long it takes to do the compilation; only take the
 805     // rest of the function into account to avoid overlap with the
 806     // parsing statistics.
 807     HistogramTimer* rate = info->is_eval()
 808           ? info->isolate()->counters()->compile_eval()
 809           : info->isolate()->counters()->compile();
 810     HistogramTimerScope timer(rate);
 811
 812     // Compile the code.
 813     if (!CompileUnoptimizedCode(info)) {
 814       return Handle<SharedFunctionInfo>::null();
 815     }
 816
 817     // Allocate function.
 818     ASSERT(!info->code().is_null());
 819     result = isolate->factory()->NewSharedFunctionInfo(
 820         lit->name(),
 821         lit->materialized_literal_count(),
 822         lit->is_generator(),
 823         info->code(),
 824         ScopeInfo::Create(info->scope(), info->zone()),
 825         info->feedback_vector());
 826
 827     ASSERT_EQ(RelocInfo::kNoPosition, lit->function_token_position());
 828     SetFunctionInfo(result, lit, true, script);
 829
 830     Handle<String> script_name = script->name()->IsString()
 831         ? Handle<String>(String::cast(script->name()))
 832         : isolate->factory()->empty_string();
 833     Logger::LogEventsAndTags log_tag = info->is_eval()
 834         ? Logger::EVAL_TAG
 835         : Logger::ToNativeByScript(Logger::SCRIPT_TAG, *script);
 836
 837     PROFILE(isolate, CodeCreateEvent(
 838                 log_tag, *info->code(), *result, info, *script_name));
 839     GDBJIT(AddCode(script_name, script, info->code(), info));
 840
 841     // Hint to the runtime system used when allocating space for initial
 842     // property space by setting the expected number of properties for
 843     // the instances of the function.
 844     SetExpectedNofPropertiesFromEstimate(result,
 845                                          lit->expected_property_count());
 846
 847     script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
 848
 849     live_edit_tracker.RecordFunctionInfo(result, lit, info->zone());
 850   }
 851
 852   isolate->debugger()->OnAfterCompile(script, Debugger::NO_AFTER_COMPILE_FLAGS);
 853
 854   return result;
 855 }
 856
 857
 858 MaybeHandle<JSFunction> Compiler::GetFunctionFromEval(
 859     Handle<String> source,
 860     Handle<Context> context,
 861     StrictMode strict_mode,
 862     ParseRestriction restriction,
 863     int scope_position) {
 864   Isolate* isolate = source->GetIsolate();
 865   int source_length = source->length();
 866   isolate->counters()->total_eval_size()->Increment(source_length);
 867   isolate->counters()->total_compile_size()->Increment(source_length);
 868
 869   CompilationCache* compilation_cache = isolate->compilation_cache();
 870   MaybeHandle<SharedFunctionInfo> maybe_shared_info =
 871       compilation_cache->LookupEval(source, context, strict_mode,
 872                                     scope_position);
 873   Handle<SharedFunctionInfo> shared_info;
 874
 875   if (!maybe_shared_info.ToHandle(&shared_info)) {
 876     Handle<Script> script = isolate->factory()->NewScript(source);
 877     CompilationInfoWithZone info(script);
 878     info.MarkAsEval();
 879     if (context->IsNativeContext()) info.MarkAsGlobal();
 880     info.SetStrictMode(strict_mode);
 881     info.SetParseRestriction(restriction);
 882     info.SetContext(context);
 883
 884     Debug::RecordEvalCaller(script);
 885
 886     shared_info = CompileToplevel(&info);
 887
 888     if (shared_info.is_null()) {
 889       return MaybeHandle<JSFunction>();
 890     } else {
 891       // Explicitly disable optimization for eval code. We're not yet prepared
 892       // to handle eval-code in the optimizing compiler.
 893       shared_info->DisableOptimization(kEval);
 894
 895       // If caller is strict mode, the result must be in strict mode as well.
 896       ASSERT(strict_mode == SLOPPY || shared_info->strict_mode() == STRICT);
 897       if (!shared_info->dont_cache()) {
 898         compilation_cache->PutEval(
 899             source, context, shared_info, scope_position);
 900       }
 901     }
 902   } else if (shared_info->ic_age() != isolate->heap()->global_ic_age()) {
 903     shared_info->ResetForNewContext(isolate->heap()->global_ic_age());
 904   }
 905
 906   return isolate->factory()->NewFunctionFromSharedFunctionInfo(
 907       shared_info, context, NOT_TENURED);
 908 }
 909
 910
 911 Handle<SharedFunctionInfo> Compiler::CompileScript(
 912     Handle<String> source,
 913     Handle<Object> script_name,
 914     int line_offset,
 915     int column_offset,
 916     bool is_shared_cross_origin,
 917     Handle<Context> context,
 918     v8::Extension* extension,
 919     ScriptData** cached_data,
 920     CachedDataMode cached_data_mode,
 921     NativesFlag natives) {
 922   if (cached_data_mode == NO_CACHED_DATA) {
 923     cached_data = NULL;
 924   } else if (cached_data_mode == PRODUCE_CACHED_DATA) {
 925     ASSERT(cached_data && !*cached_data);
 926   } else {
 927     ASSERT(cached_data_mode == CONSUME_CACHED_DATA);
 928     ASSERT(cached_data && *cached_data);
 929   }
 930   Isolate* isolate = source->GetIsolate();
 931   int source_length = source->length();
 932   isolate->counters()->total_load_size()->Increment(source_length);
 933   isolate->counters()->total_compile_size()->Increment(source_length);
 934
 935   CompilationCache* compilation_cache = isolate->compilation_cache();
 936
 937   // Do a lookup in the compilation cache but not for extensions.
 938   MaybeHandle<SharedFunctionInfo> maybe_result;
 939   Handle<SharedFunctionInfo> result;
 940   if (extension == NULL) {
 941     maybe_result = compilation_cache->LookupScript(
 942         source, script_name, line_offset, column_offset,
 943         is_shared_cross_origin, context);
 944   }
 945
 946   if (!maybe_result.ToHandle(&result)) {
 947     // No cache entry found. Compile the script.
 948
 949     // Create a script object describing the script to be compiled.
 950     Handle<Script> script = isolate->factory()->NewScript(source);
 951     if (natives == NATIVES_CODE) {
 952       script->set_type(Smi::FromInt(Script::TYPE_NATIVE));
 953     }
 954     if (!script_name.is_null()) {
 955       script->set_name(*script_name);
 956       script->set_line_offset(Smi::FromInt(line_offset));
 957       script->set_column_offset(Smi::FromInt(column_offset));
 958     }
 959     script->set_is_shared_cross_origin(is_shared_cross_origin);
 960
 961     // Compile the function and add it to the cache.
 962     CompilationInfoWithZone info(script);
 963     info.MarkAsGlobal();
 964     info.SetExtension(extension);
 965     info.SetCachedData(cached_data, cached_data_mode);
 966     info.SetContext(context);
 967     if (FLAG_use_strict) info.SetStrictMode(STRICT);
 968     result = CompileToplevel(&info);
 969     if (extension == NULL && !result.is_null() && !result->dont_cache()) {
 970       compilation_cache->PutScript(source, context, result);
 971     }
 972     if (result.is_null()) isolate->ReportPendingMessages();
 973   } else if (result->ic_age() != isolate->heap()->global_ic_age()) {
 974       result->ResetForNewContext(isolate->heap()->global_ic_age());
 975   }
 976   return result;
 977 }
 978
 979
 980 Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(FunctionLiteral* literal,
 981                                                        Handle<Script> script) {
 982   // Precondition: code has been parsed and scopes have been analyzed.
 983   CompilationInfoWithZone info(script);
 984   info.SetFunction(literal);
 985   info.PrepareForCompilation(literal->scope());
 986   info.SetStrictMode(literal->scope()->strict_mode());
 987
 988   Isolate* isolate = info.isolate();
 989   Factory* factory = isolate->factory();
 990   LiveEditFunctionTracker live_edit_tracker(isolate, literal);
 991   // Determine if the function can be lazily compiled. This is necessary to
 992   // allow some of our builtin JS files to be lazily compiled. These
 993   // builtins cannot be handled lazily by the parser, since we have to know
 994   // if a function uses the special natives syntax, which is something the
 995   // parser records.
 996   // If the debugger requests compilation for break points, we cannot be
 997   // aggressive about lazy compilation, because it might trigger compilation
 998   // of functions without an outer context when setting a breakpoint through
 999   // Debug::FindSharedFunctionInfoInScript.
1000   bool allow_lazy_without_ctx = literal->AllowsLazyCompilationWithoutContext();
1001   bool allow_lazy = literal->AllowsLazyCompilation() &&
1002       !DebuggerWantsEagerCompilation(&info, allow_lazy_without_ctx);
1003
1004   // Generate code
1005   Handle<ScopeInfo> scope_info;
1006   if (FLAG_lazy && allow_lazy && !literal->is_parenthesized()) {
1007     Handle<Code> code = isolate->builtins()->CompileUnoptimized();
1008     info.SetCode(code);
1009     scope_info = Handle<ScopeInfo>(ScopeInfo::Empty(isolate));
1010   } else if (FullCodeGenerator::MakeCode(&info)) {
1011     ASSERT(!info.code().is_null());
1012     scope_info = ScopeInfo::Create(info.scope(), info.zone());
1013   } else {
1014     return Handle<SharedFunctionInfo>::null();
1015   }
1016
1017   // Create a shared function info object.
1018   Handle<SharedFunctionInfo> result =
1019       factory->NewSharedFunctionInfo(literal->name(),
1020                                      literal->materialized_literal_count(),
1021                                      literal->is_generator(),
1022                                      info.code(),
1023                                      scope_info,
1024                                      info.feedback_vector());
1025   SetFunctionInfo(result, literal, false, script);
1026   RecordFunctionCompilation(Logger::FUNCTION_TAG, &info, result);
1027   result->set_allows_lazy_compilation(allow_lazy);
1028   result->set_allows_lazy_compilation_without_context(allow_lazy_without_ctx);
1029
1030   // Set the expected number of properties for instances and return
1031   // the resulting function.
1032   SetExpectedNofPropertiesFromEstimate(result,
1033                                        literal->expected_property_count());
1034   live_edit_tracker.RecordFunctionInfo(result, literal, info.zone());
1035   return result;
1036 }
1037
1038
1039 MUST_USE_RESULT static MaybeHandle<Code> GetCodeFromOptimizedCodeMap(
1040     Handle<JSFunction> function,
1041     BailoutId osr_ast_id) {
1042   if (FLAG_cache_optimized_code) {
1043     Handle<SharedFunctionInfo> shared(function->shared());
1044     DisallowHeapAllocation no_gc;
1045     int index = shared->SearchOptimizedCodeMap(
1046         function->context()->native_context(), osr_ast_id);
1047     if (index > 0) {
1048       if (FLAG_trace_opt) {
1049         PrintF("[found optimized code for ");
1050         function->ShortPrint();
1051         if (!osr_ast_id.IsNone()) {
1052           PrintF(" at OSR AST id %d", osr_ast_id.ToInt());
1053         }
1054         PrintF("]\n");
1055       }
1056       FixedArray* literals = shared->GetLiteralsFromOptimizedCodeMap(index);
1057       if (literals != NULL) function->set_literals(literals);
1058       return Handle<Code>(shared->GetCodeFromOptimizedCodeMap(index));
1059     }
1060   }
1061   return MaybeHandle<Code>();
1062 }
1063
1064
1065 static void InsertCodeIntoOptimizedCodeMap(CompilationInfo* info) {
1066   Handle<Code> code = info->code();
1067   if (code->kind() != Code::OPTIMIZED_FUNCTION) return;  // Nothing to do.
1068
1069   // Cache optimized code.
1070   if (FLAG_cache_optimized_code) {
1071     Handle<JSFunction> function = info->closure();
1072     Handle<SharedFunctionInfo> shared(function->shared());
1073     Handle<FixedArray> literals(function->literals());
1074     Handle<Context> native_context(function->context()->native_context());
1075     SharedFunctionInfo::AddToOptimizedCodeMap(
1076         shared, native_context, code, literals, info->osr_ast_id());
1077   }
1078 }
1079
1080
1081 static bool CompileOptimizedPrologue(CompilationInfo* info) {
1082   if (!Parser::Parse(info)) return false;
1083   info->SetStrictMode(info->function()->strict_mode());
1084
1085   if (!Rewriter::Rewrite(info)) return false;
1086   if (!Scope::Analyze(info)) return false;
1087   ASSERT(info->scope() != NULL);
1088   return true;
1089 }
1090
1091
1092 static bool GetOptimizedCodeNow(CompilationInfo* info) {
1093   if (!CompileOptimizedPrologue(info)) return false;
1094
1095   Logger::TimerEventScope timer(
1096       info->isolate(), Logger::TimerEventScope::v8_recompile_synchronous);
1097
1098   OptimizedCompileJob job(info);
1099   if (job.CreateGraph() != OptimizedCompileJob::SUCCEEDED) return false;
1100   if (job.OptimizeGraph() != OptimizedCompileJob::SUCCEEDED) return false;
1101   if (job.GenerateCode() != OptimizedCompileJob::SUCCEEDED) return false;
1102
1103   // Success!
1104   ASSERT(!info->isolate()->has_pending_exception());
1105   InsertCodeIntoOptimizedCodeMap(info);
1106   Compiler::RecordFunctionCompilation(
1107       Logger::LAZY_COMPILE_TAG, info, info->shared_info());
1108   return true;
1109 }
1110
1111
1112 static bool GetOptimizedCodeLater(CompilationInfo* info) {
1113   Isolate* isolate = info->isolate();
1114   if (!isolate->optimizing_compiler_thread()->IsQueueAvailable()) {
1115     if (FLAG_trace_concurrent_recompilation) {
1116       PrintF("  ** Compilation queue full, will retry optimizing ");
1117       info->closure()->PrintName();
1118       PrintF(" later.\n");
1119     }
1120     return false;
1121   }
1122
1123   CompilationHandleScope handle_scope(info);
1124   if (!CompileOptimizedPrologue(info)) return false;
1125   info->SaveHandles();  // Copy handles to the compilation handle scope.
1126
1127   Logger::TimerEventScope timer(
1128       isolate, Logger::TimerEventScope::v8_recompile_synchronous);
1129
1130   OptimizedCompileJob* job = new(info->zone()) OptimizedCompileJob(info);
1131   OptimizedCompileJob::Status status = job->CreateGraph();
1132   if (status != OptimizedCompileJob::SUCCEEDED) return false;
1133   isolate->optimizing_compiler_thread()->QueueForOptimization(job);
1134
1135   if (FLAG_trace_concurrent_recompilation) {
1136     PrintF("  ** Queued ");
1137      info->closure()->PrintName();
1138     if (info->is_osr()) {
1139       PrintF(" for concurrent OSR at %d.\n", info->osr_ast_id().ToInt());
1140     } else {
1141       PrintF(" for concurrent optimization.\n");
1142     }
1143   }
1144   return true;
1145 }
1146
1147
1148 MaybeHandle<Code> Compiler::GetOptimizedCode(Handle<JSFunction> function,
1149                                              Handle<Code> current_code,
1150                                              ConcurrencyMode mode,
1151                                              BailoutId osr_ast_id) {
1152   Handle<Code> cached_code;
1153   if (GetCodeFromOptimizedCodeMap(
1154           function, osr_ast_id).ToHandle(&cached_code)) {
1155     return cached_code;
1156   }
1157
1158   SmartPointer<CompilationInfo> info(new CompilationInfoWithZone(function));
1159   Isolate* isolate = info->isolate();
1160   VMState<COMPILER> state(isolate);
1161   ASSERT(!isolate->has_pending_exception());
1162   PostponeInterruptsScope postpone(isolate);
1163
1164   Handle<SharedFunctionInfo> shared = info->shared_info();
1165   ASSERT_NE(ScopeInfo::Empty(isolate), shared->scope_info());
1166   int compiled_size = shared->end_position() - shared->start_position();
1167   isolate->counters()->total_compile_size()->Increment(compiled_size);
1168   current_code->set_profiler_ticks(0);
1169
1170   info->SetOptimizing(osr_ast_id, current_code);
1171
1172   if (mode == CONCURRENT) {
1173     if (GetOptimizedCodeLater(info.get())) {
1174       info.Detach();  // The background recompile job owns this now.
1175       return isolate->builtins()->InOptimizationQueue();
1176     }
1177   } else {
1178     if (GetOptimizedCodeNow(info.get())) return info->code();
1179   }
1180
1181   // Failed.
1182   if (FLAG_trace_opt) {
1183     PrintF("[failed to optimize ");
1184     function->PrintName();
1185     PrintF(": %s]\n", GetBailoutReason(info->bailout_reason()));
1186   }
1187
1188   if (isolate->has_pending_exception()) isolate->clear_pending_exception();
1189   return MaybeHandle<Code>();
1190 }
1191
1192
1193 Handle<Code> Compiler::GetConcurrentlyOptimizedCode(OptimizedCompileJob* job) {
1194   // Take ownership of compilation info.  Deleting compilation info
1195   // also tears down the zone and the recompile job.
1196   SmartPointer<CompilationInfo> info(job->info());
1197   Isolate* isolate = info->isolate();
1198
1199   VMState<COMPILER> state(isolate);
1200   Logger::TimerEventScope timer(
1201       isolate, Logger::TimerEventScope::v8_recompile_synchronous);
1202
1203   Handle<SharedFunctionInfo> shared = info->shared_info();
1204   shared->code()->set_profiler_ticks(0);
1205
1206   // 1) Optimization may have failed.
1207   // 2) The function may have already been optimized by OSR.  Simply continue.
1208   //    Except when OSR already disabled optimization for some reason.
1209   // 3) The code may have already been invalidated due to dependency change.
1210   // 4) Debugger may have been activated.
1211
1212   if (job->last_status() != OptimizedCompileJob::SUCCEEDED ||
1213       shared->optimization_disabled() ||
1214       info->HasAbortedDueToDependencyChange() ||
1215       isolate->DebuggerHasBreakPoints()) {
1216     return Handle<Code>::null();
1217   }
1218
1219   if (job->GenerateCode() != OptimizedCompileJob::SUCCEEDED) {
1220     return Handle<Code>::null();
1221   }
1222
1223   Compiler::RecordFunctionCompilation(
1224       Logger::LAZY_COMPILE_TAG, info.get(), shared);
1225   if (info->shared_info()->SearchOptimizedCodeMap(
1226           info->context()->native_context(), info->osr_ast_id()) == -1) {
1227     InsertCodeIntoOptimizedCodeMap(info.get());
1228   }
1229
1230   if (FLAG_trace_concurrent_recompilation) {
1231     PrintF("  ** Optimized code for ");
1232     info->closure()->PrintName();
1233     PrintF(" generated.\n");
1234   }
1235
1236   return Handle<Code>(*info->code());
1237 }
1238
1239
1240 void Compiler::RecordFunctionCompilation(Logger::LogEventsAndTags tag,
1241                                          CompilationInfo* info,
1242                                          Handle<SharedFunctionInfo> shared) {
1243   // SharedFunctionInfo is passed separately, because if CompilationInfo
1244   // was created using Script object, it will not have it.
1245
1246   // Log the code generation. If source information is available include
1247   // script name and line number. Check explicitly whether logging is
1248   // enabled as finding the line number is not free.
1249   if (info->isolate()->logger()->is_logging_code_events() ||
1250       info->isolate()->cpu_profiler()->is_profiling()) {
1251     Handle<Script> script = info->script();
1252     Handle<Code> code = info->code();
1253     if (code.is_identical_to(
1254             info->isolate()->builtins()->CompileUnoptimized())) {
1255       return;
1256     }
1257     int line_num = Script::GetLineNumber(script, shared->start_position()) + 1;
1258     int column_num =
1259         Script::GetColumnNumber(script, shared->start_position()) + 1;
1260     String* script_name = script->name()->IsString()
1261         ? String::cast(script->name())
1262         : info->isolate()->heap()->empty_string();
1263     Logger::LogEventsAndTags log_tag = Logger::ToNativeByScript(tag, *script);
1264     PROFILE(info->isolate(), CodeCreateEvent(
1265         log_tag, *code, *shared, info, script_name, line_num, column_num));
1266   }
1267
1268   GDBJIT(AddCode(Handle<String>(shared->DebugName()),
1269                  Handle<Script>(info->script()),
1270                  Handle<Code>(info->code()),
1271                  info));
1272 }
1273
1274
1275 CompilationPhase::CompilationPhase(const char* name, CompilationInfo* info)
1276     : name_(name), info_(info), zone_(info->isolate()) {
1277   if (FLAG_hydrogen_stats) {
1278     info_zone_start_allocation_size_ = info->zone()->allocation_size();
1279     timer_.Start();
1280   }
1281 }
1282
1283
1284 CompilationPhase::~CompilationPhase() {
1285   if (FLAG_hydrogen_stats) {
1286     unsigned size = zone()->allocation_size();
1287     size += info_->zone()->allocation_size() - info_zone_start_allocation_size_;
1288     isolate()->GetHStatistics()->SaveTiming(name_, timer_.Elapsed(), size);
1289   }
1290 }
1291
1292
1293 bool CompilationPhase::ShouldProduceTraceOutput() const {
1294   // Trace if the appropriate trace flag is set and the phase name's first
1295   // character is in the FLAG_trace_phase command line parameter.
1296   AllowHandleDereference allow_deref;
1297   bool tracing_on = info()->IsStub()
1298       ? FLAG_trace_hydrogen_stubs
1299       : (FLAG_trace_hydrogen &&
1300          info()->closure()->PassesFilter(FLAG_trace_hydrogen_filter));
1301   return (tracing_on &&
1302       OS::StrChr(const_cast<char*>(FLAG_trace_phase), name_[0]) != NULL);
1303 }
1304
1305 } }  // namespace v8::internal