| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "src/runtime-profiler.h" |
| |
| #include "src/assembler.h" |
| #include "src/base/platform/platform.h" |
| #include "src/bootstrapper.h" |
| #include "src/code-stubs.h" |
| #include "src/compilation-cache.h" |
| #include "src/compiler.h" |
| #include "src/execution.h" |
| #include "src/frames-inl.h" |
| #include "src/full-codegen/full-codegen.h" |
| #include "src/global-handles.h" |
| #include "src/interpreter/interpreter.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| |
| // Number of times a function has to be seen on the stack before it is |
| // compiled for baseline. |
| static const int kProfilerTicksBeforeBaseline = 0; |
| // Number of times a function has to be seen on the stack before it is |
| // optimized. |
| static const int kProfilerTicksBeforeOptimization = 2; |
| // If the function optimization was disabled due to high deoptimization count, |
| // but the function is hot and has been seen on the stack this number of times, |
| // then we try to reenable optimization for this function. |
| static const int kProfilerTicksBeforeReenablingOptimization = 250; |
| // If a function does not have enough type info (according to |
| // FLAG_type_info_threshold), but has seen a huge number of ticks, |
| // optimize it as it is. |
| static const int kTicksWhenNotEnoughTypeInfo = 100; |
| // We only have one byte to store the number of ticks. |
| STATIC_ASSERT(kProfilerTicksBeforeOptimization < 256); |
| STATIC_ASSERT(kProfilerTicksBeforeReenablingOptimization < 256); |
| STATIC_ASSERT(kTicksWhenNotEnoughTypeInfo < 256); |
| |
| // Maximum size in bytes of generate code for a function to allow OSR. |
| static const int kOSRCodeSizeAllowanceBase = |
| 100 * FullCodeGenerator::kCodeSizeMultiplier; |
| static const int kOSRCodeSizeAllowanceBaseIgnition = |
| 10 * interpreter::Interpreter::kCodeSizeMultiplier; |
| |
| static const int kOSRCodeSizeAllowancePerTick = |
| 4 * FullCodeGenerator::kCodeSizeMultiplier; |
| static const int kOSRCodeSizeAllowancePerTickIgnition = |
| 2 * interpreter::Interpreter::kCodeSizeMultiplier; |
| |
| // Maximum size in bytes of generated code for a function to be optimized |
| // the very first time it is seen on the stack. |
| static const int kMaxSizeEarlyOpt = |
| 5 * FullCodeGenerator::kCodeSizeMultiplier; |
| static const int kMaxSizeEarlyOptIgnition = |
| 5 * interpreter::Interpreter::kCodeSizeMultiplier; |
| |
| // Certain functions are simply too big to be worth optimizing. |
| // We aren't using the code size multiplier here because there is no |
| // "kMaxSizeOpt" with which we would need to normalize. This constant is |
| // only for optimization decisions coming into TurboFan from Ignition. |
| static const int kMaxSizeOptIgnition = 250 * 1024; |
| |
| #define OPTIMIZATION_REASON_LIST(V) \ |
| V(DoNotOptimize, "do not optimize") \ |
| V(HotAndStable, "hot and stable") \ |
| V(HotEnoughForBaseline, "hot enough for baseline") \ |
| V(HotWithoutMuchTypeInfo, "not much type info but very hot") \ |
| V(SmallFunction, "small function") |
| |
| enum class OptimizationReason : uint8_t { |
| #define OPTIMIZATION_REASON_CONSTANTS(Constant, message) k##Constant, |
| OPTIMIZATION_REASON_LIST(OPTIMIZATION_REASON_CONSTANTS) |
| #undef OPTIMIZATION_REASON_CONSTANTS |
| }; |
| |
| char const* OptimizationReasonToString(OptimizationReason reason) { |
| static char const* reasons[] = { |
| #define OPTIMIZATION_REASON_TEXTS(Constant, message) message, |
| OPTIMIZATION_REASON_LIST(OPTIMIZATION_REASON_TEXTS) |
| #undef OPTIMIZATION_REASON_TEXTS |
| }; |
| size_t const index = static_cast<size_t>(reason); |
| DCHECK_LT(index, arraysize(reasons)); |
| return reasons[index]; |
| } |
| |
| std::ostream& operator<<(std::ostream& os, OptimizationReason reason) { |
| return os << OptimizationReasonToString(reason); |
| } |
| |
| RuntimeProfiler::RuntimeProfiler(Isolate* isolate) |
| : isolate_(isolate), |
| any_ic_changed_(false) { |
| } |
| |
| static void GetICCounts(JSFunction* function, int* ic_with_type_info_count, |
| int* ic_generic_count, int* ic_total_count, |
| int* type_info_percentage, int* generic_percentage) { |
| *ic_total_count = 0; |
| *ic_generic_count = 0; |
| *ic_with_type_info_count = 0; |
| if (function->code()->kind() == Code::FUNCTION) { |
| Code* shared_code = function->shared()->code(); |
| Object* raw_info = shared_code->type_feedback_info(); |
| if (raw_info->IsTypeFeedbackInfo()) { |
| TypeFeedbackInfo* info = TypeFeedbackInfo::cast(raw_info); |
| *ic_with_type_info_count = info->ic_with_type_info_count(); |
| *ic_generic_count = info->ic_generic_count(); |
| *ic_total_count = info->ic_total_count(); |
| } |
| } |
| |
| // Harvest vector-ics as well |
| FeedbackVector* vector = function->feedback_vector(); |
| int with = 0, gen = 0, type_vector_ic_count = 0; |
| const bool is_interpreted = function->shared()->IsInterpreted(); |
| |
| vector->ComputeCounts(&with, &gen, &type_vector_ic_count, is_interpreted); |
| *ic_total_count += type_vector_ic_count; |
| *ic_with_type_info_count += with; |
| *ic_generic_count += gen; |
| |
| if (*ic_total_count > 0) { |
| *type_info_percentage = 100 * *ic_with_type_info_count / *ic_total_count; |
| *generic_percentage = 100 * *ic_generic_count / *ic_total_count; |
| } else { |
| *type_info_percentage = 100; // Compared against lower bound. |
| *generic_percentage = 0; // Compared against upper bound. |
| } |
| } |
| |
| static void TraceRecompile(JSFunction* function, const char* reason, |
| const char* type) { |
| if (FLAG_trace_opt && |
| function->shared()->PassesFilter(FLAG_hydrogen_filter)) { |
| PrintF("[marking "); |
| function->ShortPrint(); |
| PrintF(" for %s recompilation, reason: %s", type, reason); |
| if (FLAG_type_info_threshold > 0) { |
| int typeinfo, generic, total, type_percentage, generic_percentage; |
| GetICCounts(function, &typeinfo, &generic, &total, &type_percentage, |
| &generic_percentage); |
| PrintF(", ICs with typeinfo: %d/%d (%d%%)", typeinfo, total, |
| type_percentage); |
| PrintF(", generic ICs: %d/%d (%d%%)", generic, total, generic_percentage); |
| } |
| PrintF("]\n"); |
| } |
| } |
| |
| void RuntimeProfiler::Optimize(JSFunction* function, |
| OptimizationReason reason) { |
| DCHECK_NE(reason, OptimizationReason::kDoNotOptimize); |
| TraceRecompile(function, OptimizationReasonToString(reason), "optimized"); |
| function->AttemptConcurrentOptimization(); |
| } |
| |
| void RuntimeProfiler::Baseline(JSFunction* function, |
| OptimizationReason reason) { |
| DCHECK_NE(reason, OptimizationReason::kDoNotOptimize); |
| TraceRecompile(function, OptimizationReasonToString(reason), "baseline"); |
| DCHECK(function->shared()->IsInterpreted()); |
| function->MarkForBaseline(); |
| } |
| |
| void RuntimeProfiler::AttemptOnStackReplacement(JavaScriptFrame* frame, |
| int loop_nesting_levels) { |
| JSFunction* function = frame->function(); |
| SharedFunctionInfo* shared = function->shared(); |
| if (!FLAG_use_osr || !function->shared()->IsUserJavaScript()) { |
| return; |
| } |
| |
| // If the code is not optimizable, don't try OSR. |
| if (shared->optimization_disabled()) return; |
| |
| // We are not prepared to do OSR for a function that already has an |
| // allocated arguments object. The optimized code would bypass it for |
| // arguments accesses, which is unsound. Don't try OSR. |
| if (shared->uses_arguments()) return; |
| |
| // We're using on-stack replacement: modify unoptimized code so that |
| // certain back edges in any unoptimized frame will trigger on-stack |
| // replacement for that frame. |
| // - Ignition: Store new loop nesting level in BytecodeArray header. |
| // - FullCodegen: Patch back edges up to new level using BackEdgeTable. |
| if (FLAG_trace_osr) { |
| PrintF("[OSR - arming back edges in "); |
| function->PrintName(); |
| PrintF("]\n"); |
| } |
| |
| if (frame->type() == StackFrame::JAVA_SCRIPT) { |
| DCHECK(shared->HasBaselineCode()); |
| DCHECK(BackEdgeTable::Verify(shared->GetIsolate(), shared->code())); |
| for (int i = 0; i < loop_nesting_levels; i++) { |
| BackEdgeTable::Patch(isolate_, shared->code()); |
| } |
| } else if (frame->type() == StackFrame::INTERPRETED) { |
| DCHECK(shared->HasBytecodeArray()); |
| if (!FLAG_ignition_osr) return; // Only use this when enabled. |
| int level = shared->bytecode_array()->osr_loop_nesting_level(); |
| shared->bytecode_array()->set_osr_loop_nesting_level( |
| Min(level + loop_nesting_levels, AbstractCode::kMaxLoopNestingMarker)); |
| } else { |
| UNREACHABLE(); |
| } |
| } |
| |
| void RuntimeProfiler::MaybeOptimizeFullCodegen(JSFunction* function, |
| JavaScriptFrame* frame, |
| int frame_count) { |
| SharedFunctionInfo* shared = function->shared(); |
| Code* shared_code = shared->code(); |
| if (shared_code->kind() != Code::FUNCTION) return; |
| if (function->IsInOptimizationQueue()) return; |
| |
| if (FLAG_always_osr) { |
| AttemptOnStackReplacement(frame, AbstractCode::kMaxLoopNestingMarker); |
| // Fall through and do a normal optimized compile as well. |
| } else if (!frame->is_optimized() && |
| (function->IsMarkedForOptimization() || |
| function->IsMarkedForConcurrentOptimization() || |
| function->IsOptimized())) { |
| // Attempt OSR if we are still running unoptimized code even though the |
| // the function has long been marked or even already been optimized. |
| int ticks = shared_code->profiler_ticks(); |
| int64_t allowance = |
| kOSRCodeSizeAllowanceBase + |
| static_cast<int64_t>(ticks) * kOSRCodeSizeAllowancePerTick; |
| if (shared_code->CodeSize() > allowance && |
| ticks < Code::ProfilerTicksField::kMax) { |
| shared_code->set_profiler_ticks(ticks + 1); |
| } else { |
| AttemptOnStackReplacement(frame); |
| } |
| return; |
| } |
| |
| // Only record top-level code on top of the execution stack and |
| // avoid optimizing excessively large scripts since top-level code |
| // will be executed only once. |
| const int kMaxToplevelSourceSize = 10 * 1024; |
| if (shared->is_toplevel() && |
| (frame_count > 1 || shared->SourceSize() > kMaxToplevelSourceSize)) { |
| return; |
| } |
| |
| // Do not record non-optimizable functions. |
| if (shared->optimization_disabled()) { |
| if (shared->deopt_count() >= FLAG_max_opt_count) { |
| // If optimization was disabled due to many deoptimizations, |
| // then check if the function is hot and try to reenable optimization. |
| int ticks = shared_code->profiler_ticks(); |
| if (ticks >= kProfilerTicksBeforeReenablingOptimization) { |
| shared_code->set_profiler_ticks(0); |
| shared->TryReenableOptimization(); |
| } else { |
| shared_code->set_profiler_ticks(ticks + 1); |
| } |
| } |
| return; |
| } |
| if (frame->is_optimized()) return; |
| |
| int ticks = shared_code->profiler_ticks(); |
| |
| if (ticks >= kProfilerTicksBeforeOptimization) { |
| int typeinfo, generic, total, type_percentage, generic_percentage; |
| GetICCounts(function, &typeinfo, &generic, &total, &type_percentage, |
| &generic_percentage); |
| if (type_percentage >= FLAG_type_info_threshold && |
| generic_percentage <= FLAG_generic_ic_threshold) { |
| // If this particular function hasn't had any ICs patched for enough |
| // ticks, optimize it now. |
| Optimize(function, OptimizationReason::kHotAndStable); |
| } else if (ticks >= kTicksWhenNotEnoughTypeInfo) { |
| Optimize(function, OptimizationReason::kHotWithoutMuchTypeInfo); |
| } else { |
| shared_code->set_profiler_ticks(ticks + 1); |
| if (FLAG_trace_opt_verbose) { |
| PrintF("[not yet optimizing "); |
| function->PrintName(); |
| PrintF(", not enough type info: %d/%d (%d%%)]\n", typeinfo, total, |
| type_percentage); |
| } |
| } |
| } else if (!any_ic_changed_ && |
| shared_code->instruction_size() < kMaxSizeEarlyOpt) { |
| // If no IC was patched since the last tick and this function is very |
| // small, optimistically optimize it now. |
| int typeinfo, generic, total, type_percentage, generic_percentage; |
| GetICCounts(function, &typeinfo, &generic, &total, &type_percentage, |
| &generic_percentage); |
| if (type_percentage >= FLAG_type_info_threshold && |
| generic_percentage <= FLAG_generic_ic_threshold) { |
| Optimize(function, OptimizationReason::kSmallFunction); |
| } else { |
| shared_code->set_profiler_ticks(ticks + 1); |
| } |
| } else { |
| shared_code->set_profiler_ticks(ticks + 1); |
| } |
| } |
| |
| void RuntimeProfiler::MaybeBaselineIgnition(JSFunction* function, |
| JavaScriptFrame* frame) { |
| if (function->IsInOptimizationQueue()) return; |
| |
| if (FLAG_always_osr) { |
| AttemptOnStackReplacement(frame, AbstractCode::kMaxLoopNestingMarker); |
| // Fall through and do a normal baseline compile as well. |
| } else if (MaybeOSRIgnition(function, frame)) { |
| return; |
| } |
| |
| SharedFunctionInfo* shared = function->shared(); |
| int ticks = shared->profiler_ticks(); |
| |
| if (shared->optimization_disabled() && |
| shared->disable_optimization_reason() == kOptimizationDisabledForTest) { |
| // Don't baseline functions which have been marked by NeverOptimizeFunction |
| // in a test. |
| return; |
| } |
| |
| if (ticks >= kProfilerTicksBeforeBaseline) { |
| Baseline(function, OptimizationReason::kHotEnoughForBaseline); |
| } |
| } |
| |
| void RuntimeProfiler::MaybeOptimizeIgnition(JSFunction* function, |
| JavaScriptFrame* frame) { |
| if (function->IsInOptimizationQueue()) return; |
| |
| if (FLAG_always_osr) { |
| AttemptOnStackReplacement(frame, AbstractCode::kMaxLoopNestingMarker); |
| // Fall through and do a normal optimized compile as well. |
| } else if (MaybeOSRIgnition(function, frame)) { |
| return; |
| } |
| |
| SharedFunctionInfo* shared = function->shared(); |
| int ticks = shared->profiler_ticks(); |
| |
| if (shared->optimization_disabled()) { |
| if (shared->deopt_count() >= FLAG_max_opt_count) { |
| // If optimization was disabled due to many deoptimizations, |
| // then check if the function is hot and try to reenable optimization. |
| if (ticks >= kProfilerTicksBeforeReenablingOptimization) { |
| shared->set_profiler_ticks(0); |
| shared->TryReenableOptimization(); |
| } |
| } |
| return; |
| } |
| |
| if (frame->is_optimized()) return; |
| |
| OptimizationReason reason = ShouldOptimizeIgnition(function, frame); |
| |
| if (reason != OptimizationReason::kDoNotOptimize) { |
| Optimize(function, reason); |
| } |
| } |
| |
| bool RuntimeProfiler::MaybeOSRIgnition(JSFunction* function, |
| JavaScriptFrame* frame) { |
| SharedFunctionInfo* shared = function->shared(); |
| int ticks = shared->profiler_ticks(); |
| |
| // TODO(rmcilroy): Also ensure we only OSR top-level code if it is smaller |
| // than kMaxToplevelSourceSize. |
| |
| bool osr_before_baselined = function->IsMarkedForBaseline() && |
| ShouldOptimizeIgnition(function, frame) != |
| OptimizationReason::kDoNotOptimize; |
| if (!frame->is_optimized() && |
| (osr_before_baselined || function->IsMarkedForOptimization() || |
| function->IsMarkedForConcurrentOptimization() || |
| function->IsOptimized())) { |
| // Attempt OSR if we are still running interpreted code even though the |
| // the function has long been marked or even already been optimized. |
| int64_t allowance = |
| kOSRCodeSizeAllowanceBaseIgnition + |
| static_cast<int64_t>(ticks) * kOSRCodeSizeAllowancePerTickIgnition; |
| if (shared->bytecode_array()->Size() <= allowance) { |
| AttemptOnStackReplacement(frame); |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| OptimizationReason RuntimeProfiler::ShouldOptimizeIgnition( |
| JSFunction* function, JavaScriptFrame* frame) { |
| SharedFunctionInfo* shared = function->shared(); |
| int ticks = shared->profiler_ticks(); |
| |
| if (shared->bytecode_array()->Size() > kMaxSizeOptIgnition) { |
| return OptimizationReason::kDoNotOptimize; |
| } |
| |
| if (ticks >= kProfilerTicksBeforeOptimization) { |
| int typeinfo, generic, total, type_percentage, generic_percentage; |
| GetICCounts(function, &typeinfo, &generic, &total, &type_percentage, |
| &generic_percentage); |
| if (type_percentage >= FLAG_type_info_threshold) { |
| // If this particular function hasn't had any ICs patched for enough |
| // ticks, optimize it now. |
| return OptimizationReason::kHotAndStable; |
| } else if (ticks >= kTicksWhenNotEnoughTypeInfo) { |
| return OptimizationReason::kHotWithoutMuchTypeInfo; |
| } else { |
| if (FLAG_trace_opt_verbose) { |
| PrintF("[not yet optimizing "); |
| function->PrintName(); |
| PrintF(", not enough type info: %d/%d (%d%%)]\n", typeinfo, total, |
| type_percentage); |
| } |
| return OptimizationReason::kDoNotOptimize; |
| } |
| } else if (!any_ic_changed_ && |
| shared->bytecode_array()->Size() < kMaxSizeEarlyOptIgnition) { |
| // If no IC was patched since the last tick and this function is very |
| // small, optimistically optimize it now. |
| int typeinfo, generic, total, type_percentage, generic_percentage; |
| GetICCounts(function, &typeinfo, &generic, &total, &type_percentage, |
| &generic_percentage); |
| if (type_percentage >= FLAG_type_info_threshold) { |
| return OptimizationReason::kSmallFunction; |
| } |
| } |
| return OptimizationReason::kDoNotOptimize; |
| } |
| |
| void RuntimeProfiler::MarkCandidatesForOptimization() { |
| HandleScope scope(isolate_); |
| |
| if (!isolate_->use_crankshaft()) return; |
| |
| DisallowHeapAllocation no_gc; |
| |
| // Run through the JavaScript frames and collect them. If we already |
| // have a sample of the function, we mark it for optimizations |
| // (eagerly or lazily). |
| int frame_count = 0; |
| int frame_count_limit = FLAG_frame_count; |
| for (JavaScriptFrameIterator it(isolate_); |
| frame_count++ < frame_count_limit && !it.done(); |
| it.Advance()) { |
| JavaScriptFrame* frame = it.frame(); |
| JSFunction* function = frame->function(); |
| |
| Compiler::CompilationTier next_tier = |
| Compiler::NextCompilationTier(function); |
| if (function->shared()->IsInterpreted()) { |
| if (next_tier == Compiler::BASELINE) { |
| MaybeBaselineIgnition(function, frame); |
| } else { |
| DCHECK_EQ(next_tier, Compiler::OPTIMIZED); |
| MaybeOptimizeIgnition(function, frame); |
| } |
| } else { |
| DCHECK_EQ(next_tier, Compiler::OPTIMIZED); |
| MaybeOptimizeFullCodegen(function, frame, frame_count); |
| } |
| |
| // Update shared function info ticks after checking for whether functions |
| // should be optimized to keep FCG (which updates ticks on code) and |
| // Ignition (which updates ticks on shared function info) in sync. |
| List<SharedFunctionInfo*> functions(4); |
| frame->GetFunctions(&functions); |
| for (int i = functions.length(); --i >= 0;) { |
| SharedFunctionInfo* shared_function_info = functions[i]; |
| int ticks = shared_function_info->profiler_ticks(); |
| if (ticks < Smi::kMaxValue) { |
| shared_function_info->set_profiler_ticks(ticks + 1); |
| } |
| } |
| } |
| any_ic_changed_ = false; |
| } |
| |
| } // namespace internal |
| } // namespace v8 |