| // Copyright 2011 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #include "v8.h" |
| |
| #include "assembler.h" |
| #include "compilation-cache.h" |
| #include "serialize.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| |
| // The number of generations for each sub cache. |
| // The number of ScriptGenerations is carefully chosen based on histograms. |
| // See issue 458: http://code.google.com/p/v8/issues/detail?id=458 |
| static const int kScriptGenerations = 5; |
| static const int kEvalGlobalGenerations = 2; |
| static const int kEvalContextualGenerations = 2; |
| static const int kRegExpGenerations = 2; |
| |
| // Initial size of each compilation cache table allocated. |
| static const int kInitialCacheSize = 64; |
| |
| |
| CompilationCache::CompilationCache(Isolate* isolate) |
| : isolate_(isolate), |
| script_(isolate, kScriptGenerations), |
| eval_global_(isolate, kEvalGlobalGenerations), |
| eval_contextual_(isolate, kEvalContextualGenerations), |
| reg_exp_(isolate, kRegExpGenerations), |
| enabled_(true) { |
| CompilationSubCache* subcaches[kSubCacheCount] = |
| {&script_, &eval_global_, &eval_contextual_, ®_exp_}; |
| for (int i = 0; i < kSubCacheCount; ++i) { |
| subcaches_[i] = subcaches[i]; |
| } |
| } |
| |
| |
| CompilationCache::~CompilationCache() {} |
| |
| |
| static Handle<CompilationCacheTable> AllocateTable(Isolate* isolate, int size) { |
| CALL_HEAP_FUNCTION(isolate, |
| CompilationCacheTable::Allocate(isolate->heap(), size), |
| CompilationCacheTable); |
| } |
| |
| |
| Handle<CompilationCacheTable> CompilationSubCache::GetTable(int generation) { |
| ASSERT(generation < generations_); |
| Handle<CompilationCacheTable> result; |
| if (tables_[generation]->IsUndefined()) { |
| result = AllocateTable(isolate(), kInitialCacheSize); |
| tables_[generation] = *result; |
| } else { |
| CompilationCacheTable* table = |
| CompilationCacheTable::cast(tables_[generation]); |
| result = Handle<CompilationCacheTable>(table, isolate()); |
| } |
| return result; |
| } |
| |
| |
| void CompilationSubCache::Age() { |
| // Age the generations implicitly killing off the oldest. |
| for (int i = generations_ - 1; i > 0; i--) { |
| tables_[i] = tables_[i - 1]; |
| } |
| |
| // Set the first generation as unborn. |
| tables_[0] = isolate()->heap()->undefined_value(); |
| } |
| |
| |
| void CompilationSubCache::IterateFunctions(ObjectVisitor* v) { |
| Object* undefined = isolate()->heap()->undefined_value(); |
| for (int i = 0; i < generations_; i++) { |
| if (tables_[i] != undefined) { |
| reinterpret_cast<CompilationCacheTable*>(tables_[i])->IterateElements(v); |
| } |
| } |
| } |
| |
| |
| void CompilationSubCache::Iterate(ObjectVisitor* v) { |
| v->VisitPointers(&tables_[0], &tables_[generations_]); |
| } |
| |
| |
| void CompilationSubCache::Clear() { |
| MemsetPointer(tables_, isolate()->heap()->undefined_value(), generations_); |
| } |
| |
| |
| void CompilationSubCache::Remove(Handle<SharedFunctionInfo> function_info) { |
| // Probe the script generation tables. Make sure not to leak handles |
| // into the caller's handle scope. |
| { HandleScope scope(isolate()); |
| for (int generation = 0; generation < generations(); generation++) { |
| Handle<CompilationCacheTable> table = GetTable(generation); |
| table->Remove(*function_info); |
| } |
| } |
| } |
| |
| |
| CompilationCacheScript::CompilationCacheScript(Isolate* isolate, |
| int generations) |
| : CompilationSubCache(isolate, generations), |
| script_histogram_(NULL), |
| script_histogram_initialized_(false) { } |
| |
| |
| // We only re-use a cached function for some script source code if the |
| // script originates from the same place. This is to avoid issues |
| // when reporting errors, etc. |
| bool CompilationCacheScript::HasOrigin( |
| Handle<SharedFunctionInfo> function_info, |
| Handle<Object> name, |
| int line_offset, |
| int column_offset, |
| bool is_shared_cross_origin) { |
| Handle<Script> script = |
| Handle<Script>(Script::cast(function_info->script()), isolate()); |
| // If the script name isn't set, the boilerplate script should have |
| // an undefined name to have the same origin. |
| if (name.is_null()) { |
| return script->name()->IsUndefined(); |
| } |
| // Do the fast bailout checks first. |
| if (line_offset != script->line_offset()->value()) return false; |
| if (column_offset != script->column_offset()->value()) return false; |
| // Check that both names are strings. If not, no match. |
| if (!name->IsString() || !script->name()->IsString()) return false; |
| // Were both scripts tagged by the embedder as being shared cross-origin? |
| if (is_shared_cross_origin != script->is_shared_cross_origin()) return false; |
| // Compare the two name strings for equality. |
| return String::Equals(Handle<String>::cast(name), |
| Handle<String>(String::cast(script->name()))); |
| } |
| |
| |
| // TODO(245): Need to allow identical code from different contexts to |
| // be cached in the same script generation. Currently the first use |
| // will be cached, but subsequent code from different source / line |
| // won't. |
| Handle<SharedFunctionInfo> CompilationCacheScript::Lookup( |
| Handle<String> source, |
| Handle<Object> name, |
| int line_offset, |
| int column_offset, |
| bool is_shared_cross_origin, |
| Handle<Context> context) { |
| Object* result = NULL; |
| int generation; |
| |
| // Probe the script generation tables. Make sure not to leak handles |
| // into the caller's handle scope. |
| { HandleScope scope(isolate()); |
| for (generation = 0; generation < generations(); generation++) { |
| Handle<CompilationCacheTable> table = GetTable(generation); |
| Handle<Object> probe = table->Lookup(source, context); |
| if (probe->IsSharedFunctionInfo()) { |
| Handle<SharedFunctionInfo> function_info = |
| Handle<SharedFunctionInfo>::cast(probe); |
| // Break when we've found a suitable shared function info that |
| // matches the origin. |
| if (HasOrigin(function_info, |
| name, |
| line_offset, |
| column_offset, |
| is_shared_cross_origin)) { |
| result = *function_info; |
| break; |
| } |
| } |
| } |
| } |
| |
| if (!script_histogram_initialized_) { |
| script_histogram_ = isolate()->stats_table()->CreateHistogram( |
| "V8.ScriptCache", |
| 0, |
| kScriptGenerations, |
| kScriptGenerations + 1); |
| script_histogram_initialized_ = true; |
| } |
| |
| if (script_histogram_ != NULL) { |
| // The level NUMBER_OF_SCRIPT_GENERATIONS is equivalent to a cache miss. |
| isolate()->stats_table()->AddHistogramSample(script_histogram_, generation); |
| } |
| |
| // Once outside the manacles of the handle scope, we need to recheck |
| // to see if we actually found a cached script. If so, we return a |
| // handle created in the caller's handle scope. |
| if (result != NULL) { |
| Handle<SharedFunctionInfo> shared(SharedFunctionInfo::cast(result), |
| isolate()); |
| ASSERT(HasOrigin(shared, |
| name, |
| line_offset, |
| column_offset, |
| is_shared_cross_origin)); |
| // If the script was found in a later generation, we promote it to |
| // the first generation to let it survive longer in the cache. |
| if (generation != 0) Put(source, context, shared); |
| isolate()->counters()->compilation_cache_hits()->Increment(); |
| return shared; |
| } else { |
| isolate()->counters()->compilation_cache_misses()->Increment(); |
| return Handle<SharedFunctionInfo>::null(); |
| } |
| } |
| |
| |
| void CompilationCacheScript::Put(Handle<String> source, |
| Handle<Context> context, |
| Handle<SharedFunctionInfo> function_info) { |
| HandleScope scope(isolate()); |
| Handle<CompilationCacheTable> table = GetFirstTable(); |
| SetFirstTable( |
| CompilationCacheTable::Put(table, source, context, function_info)); |
| } |
| |
| |
| MaybeHandle<SharedFunctionInfo> CompilationCacheEval::Lookup( |
| Handle<String> source, |
| Handle<Context> context, |
| StrictMode strict_mode, |
| int scope_position) { |
| HandleScope scope(isolate()); |
| // Make sure not to leak the table into the surrounding handle |
| // scope. Otherwise, we risk keeping old tables around even after |
| // having cleared the cache. |
| Handle<Object> result = isolate()->factory()->undefined_value(); |
| int generation; |
| for (generation = 0; generation < generations(); generation++) { |
| Handle<CompilationCacheTable> table = GetTable(generation); |
| result = table->LookupEval(source, context, strict_mode, scope_position); |
| if (result->IsSharedFunctionInfo()) break; |
| } |
| if (result->IsSharedFunctionInfo()) { |
| Handle<SharedFunctionInfo> function_info = |
| Handle<SharedFunctionInfo>::cast(result); |
| if (generation != 0) { |
| Put(source, context, function_info, scope_position); |
| } |
| isolate()->counters()->compilation_cache_hits()->Increment(); |
| return scope.CloseAndEscape(function_info); |
| } else { |
| isolate()->counters()->compilation_cache_misses()->Increment(); |
| return MaybeHandle<SharedFunctionInfo>(); |
| } |
| } |
| |
| |
| void CompilationCacheEval::Put(Handle<String> source, |
| Handle<Context> context, |
| Handle<SharedFunctionInfo> function_info, |
| int scope_position) { |
| HandleScope scope(isolate()); |
| Handle<CompilationCacheTable> table = GetFirstTable(); |
| table = CompilationCacheTable::PutEval(table, source, context, |
| function_info, scope_position); |
| SetFirstTable(table); |
| } |
| |
| |
| MaybeHandle<FixedArray> CompilationCacheRegExp::Lookup( |
| Handle<String> source, |
| JSRegExp::Flags flags) { |
| HandleScope scope(isolate()); |
| // Make sure not to leak the table into the surrounding handle |
| // scope. Otherwise, we risk keeping old tables around even after |
| // having cleared the cache. |
| Handle<Object> result = isolate()->factory()->undefined_value(); |
| int generation; |
| for (generation = 0; generation < generations(); generation++) { |
| Handle<CompilationCacheTable> table = GetTable(generation); |
| result = table->LookupRegExp(source, flags); |
| if (result->IsFixedArray()) break; |
| } |
| if (result->IsFixedArray()) { |
| Handle<FixedArray> data = Handle<FixedArray>::cast(result); |
| if (generation != 0) { |
| Put(source, flags, data); |
| } |
| isolate()->counters()->compilation_cache_hits()->Increment(); |
| return scope.CloseAndEscape(data); |
| } else { |
| isolate()->counters()->compilation_cache_misses()->Increment(); |
| return MaybeHandle<FixedArray>(); |
| } |
| } |
| |
| |
| void CompilationCacheRegExp::Put(Handle<String> source, |
| JSRegExp::Flags flags, |
| Handle<FixedArray> data) { |
| HandleScope scope(isolate()); |
| Handle<CompilationCacheTable> table = GetFirstTable(); |
| SetFirstTable(CompilationCacheTable::PutRegExp(table, source, flags, data)); |
| } |
| |
| |
| void CompilationCache::Remove(Handle<SharedFunctionInfo> function_info) { |
| if (!IsEnabled()) return; |
| |
| eval_global_.Remove(function_info); |
| eval_contextual_.Remove(function_info); |
| script_.Remove(function_info); |
| } |
| |
| |
| MaybeHandle<SharedFunctionInfo> CompilationCache::LookupScript( |
| Handle<String> source, |
| Handle<Object> name, |
| int line_offset, |
| int column_offset, |
| bool is_shared_cross_origin, |
| Handle<Context> context) { |
| if (!IsEnabled()) return MaybeHandle<SharedFunctionInfo>(); |
| |
| return script_.Lookup(source, name, line_offset, column_offset, |
| is_shared_cross_origin, context); |
| } |
| |
| |
| MaybeHandle<SharedFunctionInfo> CompilationCache::LookupEval( |
| Handle<String> source, |
| Handle<Context> context, |
| StrictMode strict_mode, |
| int scope_position) { |
| if (!IsEnabled()) return MaybeHandle<SharedFunctionInfo>(); |
| |
| MaybeHandle<SharedFunctionInfo> result; |
| if (context->IsNativeContext()) { |
| result = eval_global_.Lookup( |
| source, context, strict_mode, scope_position); |
| } else { |
| ASSERT(scope_position != RelocInfo::kNoPosition); |
| result = eval_contextual_.Lookup( |
| source, context, strict_mode, scope_position); |
| } |
| return result; |
| } |
| |
| |
| MaybeHandle<FixedArray> CompilationCache::LookupRegExp(Handle<String> source, |
| JSRegExp::Flags flags) { |
| if (!IsEnabled()) return MaybeHandle<FixedArray>(); |
| |
| return reg_exp_.Lookup(source, flags); |
| } |
| |
| |
| void CompilationCache::PutScript(Handle<String> source, |
| Handle<Context> context, |
| Handle<SharedFunctionInfo> function_info) { |
| if (!IsEnabled()) return; |
| |
| script_.Put(source, context, function_info); |
| } |
| |
| |
| void CompilationCache::PutEval(Handle<String> source, |
| Handle<Context> context, |
| Handle<SharedFunctionInfo> function_info, |
| int scope_position) { |
| if (!IsEnabled()) return; |
| |
| HandleScope scope(isolate()); |
| if (context->IsNativeContext()) { |
| eval_global_.Put(source, context, function_info, scope_position); |
| } else { |
| ASSERT(scope_position != RelocInfo::kNoPosition); |
| eval_contextual_.Put(source, context, function_info, scope_position); |
| } |
| } |
| |
| |
| |
| void CompilationCache::PutRegExp(Handle<String> source, |
| JSRegExp::Flags flags, |
| Handle<FixedArray> data) { |
| if (!IsEnabled()) { |
| return; |
| } |
| |
| reg_exp_.Put(source, flags, data); |
| } |
| |
| |
| void CompilationCache::Clear() { |
| for (int i = 0; i < kSubCacheCount; i++) { |
| subcaches_[i]->Clear(); |
| } |
| } |
| |
| |
| void CompilationCache::Iterate(ObjectVisitor* v) { |
| for (int i = 0; i < kSubCacheCount; i++) { |
| subcaches_[i]->Iterate(v); |
| } |
| } |
| |
| |
| void CompilationCache::IterateFunctions(ObjectVisitor* v) { |
| for (int i = 0; i < kSubCacheCount; i++) { |
| subcaches_[i]->IterateFunctions(v); |
| } |
| } |
| |
| |
| void CompilationCache::MarkCompactPrologue() { |
| for (int i = 0; i < kSubCacheCount; i++) { |
| subcaches_[i]->Age(); |
| } |
| } |
| |
| |
| void CompilationCache::Enable() { |
| enabled_ = true; |
| } |
| |
| |
| void CompilationCache::Disable() { |
| enabled_ = false; |
| Clear(); |
| } |
| |
| |
| } } // namespace v8::internal |