// Copyright 2012 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. #ifndef V8_COMPILATION_CACHE_H_ #define V8_COMPILATION_CACHE_H_ namespace v8 { namespace internal { // The compilation cache consists of several generational sub-caches which uses // this class as a base class. A sub-cache contains a compilation cache tables // for each generation of the sub-cache. Since the same source code string has // different compiled code for scripts and evals, we use separate sub-caches // for different compilation modes, to avoid retrieving the wrong result. class CompilationSubCache { public: CompilationSubCache(Isolate* isolate, int generations) : isolate_(isolate), generations_(generations) { tables_ = NewArray<Object*>(generations); } ~CompilationSubCache() { DeleteArray(tables_); } // Index for the first generation in the cache. static const int kFirstGeneration = 0; // Get the compilation cache tables for a specific generation. Handle<CompilationCacheTable> GetTable(int generation); // Accessors for first generation. Handle<CompilationCacheTable> GetFirstTable() { return GetTable(kFirstGeneration); } void SetFirstTable(Handle<CompilationCacheTable> value) { ASSERT(kFirstGeneration < generations_); tables_[kFirstGeneration] = *value; } // Age the sub-cache by evicting the oldest generation and creating a new // young generation. void Age(); // GC support. void Iterate(ObjectVisitor* v); void IterateFunctions(ObjectVisitor* v); // Clear this sub-cache evicting all its content. void Clear(); // Remove given shared function info from sub-cache. void Remove(Handle<SharedFunctionInfo> function_info); // Number of generations in this sub-cache. inline int generations() { return generations_; } protected: Isolate* isolate() { return isolate_; } private: Isolate* isolate_; int generations_; // Number of generations. Object** tables_; // Compilation cache tables - one for each generation. DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationSubCache); }; // Sub-cache for scripts. class CompilationCacheScript : public CompilationSubCache { public: CompilationCacheScript(Isolate* isolate, int generations); Handle<SharedFunctionInfo> Lookup(Handle<String> source, Handle<Object> name, int line_offset, int column_offset); void Put(Handle<String> source, Handle<SharedFunctionInfo> function_info); private: MUST_USE_RESULT MaybeObject* TryTablePut( Handle<String> source, Handle<SharedFunctionInfo> function_info); // Note: Returns a new hash table if operation results in expansion. Handle<CompilationCacheTable> TablePut( Handle<String> source, Handle<SharedFunctionInfo> function_info); bool HasOrigin(Handle<SharedFunctionInfo> function_info, Handle<Object> name, int line_offset, int column_offset); void* script_histogram_; bool script_histogram_initialized_; DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheScript); }; // Sub-cache for eval scripts. Two caches for eval are used. One for eval calls // in global contexts and one for eval calls in other contexts. The cache // considers the following pieces of information when checking for matching // entries: // 1. The source string. // 2. The shared function info of the calling function. // 3. Whether the source should be compiled as strict code or as non-strict // code. // Note: Currently there are clients of CompileEval that always compile // non-strict code even if the calling function is a strict mode function. // More specifically these are the CompileString, DebugEvaluate and // DebugEvaluateGlobal runtime functions. // 4. The start position of the calling scope. class CompilationCacheEval: public CompilationSubCache { public: CompilationCacheEval(Isolate* isolate, int generations) : CompilationSubCache(isolate, generations) { } Handle<SharedFunctionInfo> Lookup(Handle<String> source, Handle<Context> context, LanguageMode language_mode, int scope_position); void Put(Handle<String> source, Handle<Context> context, Handle<SharedFunctionInfo> function_info, int scope_position); private: MUST_USE_RESULT MaybeObject* TryTablePut( Handle<String> source, Handle<Context> context, Handle<SharedFunctionInfo> function_info, int scope_position); // Note: Returns a new hash table if operation results in expansion. Handle<CompilationCacheTable> TablePut( Handle<String> source, Handle<Context> context, Handle<SharedFunctionInfo> function_info, int scope_position); DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheEval); }; // Sub-cache for regular expressions. class CompilationCacheRegExp: public CompilationSubCache { public: CompilationCacheRegExp(Isolate* isolate, int generations) : CompilationSubCache(isolate, generations) { } Handle<FixedArray> Lookup(Handle<String> source, JSRegExp::Flags flags); void Put(Handle<String> source, JSRegExp::Flags flags, Handle<FixedArray> data); private: MUST_USE_RESULT MaybeObject* TryTablePut(Handle<String> source, JSRegExp::Flags flags, Handle<FixedArray> data); // Note: Returns a new hash table if operation results in expansion. Handle<CompilationCacheTable> TablePut(Handle<String> source, JSRegExp::Flags flags, Handle<FixedArray> data); DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheRegExp); }; // The compilation cache keeps shared function infos for compiled // scripts and evals. The shared function infos are looked up using // the source string as the key. For regular expressions the // compilation data is cached. class CompilationCache { public: // Finds the script shared function info for a source // string. Returns an empty handle if the cache doesn't contain a // script for the given source string with the right origin. Handle<SharedFunctionInfo> LookupScript(Handle<String> source, Handle<Object> name, int line_offset, int column_offset); // Finds the shared function info for a source string for eval in a // given context. Returns an empty handle if the cache doesn't // contain a script for the given source string. Handle<SharedFunctionInfo> LookupEval(Handle<String> source, Handle<Context> context, bool is_global, LanguageMode language_mode, int scope_position); // Returns the regexp data associated with the given regexp if it // is in cache, otherwise an empty handle. Handle<FixedArray> LookupRegExp(Handle<String> source, JSRegExp::Flags flags); // Associate the (source, kind) pair to the shared function // info. This may overwrite an existing mapping. void PutScript(Handle<String> source, Handle<SharedFunctionInfo> function_info); // Associate the (source, context->closure()->shared(), kind) triple // with the shared function info. This may overwrite an existing mapping. void PutEval(Handle<String> source, Handle<Context> context, bool is_global, Handle<SharedFunctionInfo> function_info, int scope_position); // Associate the (source, flags) pair to the given regexp data. // This may overwrite an existing mapping. void PutRegExp(Handle<String> source, JSRegExp::Flags flags, Handle<FixedArray> data); // Clear the cache - also used to initialize the cache at startup. void Clear(); // Remove given shared function info from all caches. void Remove(Handle<SharedFunctionInfo> function_info); // GC support. void Iterate(ObjectVisitor* v); void IterateFunctions(ObjectVisitor* v); // Notify the cache that a mark-sweep garbage collection is about to // take place. This is used to retire entries from the cache to // avoid keeping them alive too long without using them. void MarkCompactPrologue(); // Enable/disable compilation cache. Used by debugger to disable compilation // cache during debugging to make sure new scripts are always compiled. void Enable(); void Disable(); private: explicit CompilationCache(Isolate* isolate); ~CompilationCache(); HashMap* EagerOptimizingSet(); // The number of sub caches covering the different types to cache. static const int kSubCacheCount = 4; bool IsEnabled() { return FLAG_compilation_cache && enabled_; } Isolate* isolate() { return isolate_; } Isolate* isolate_; CompilationCacheScript script_; CompilationCacheEval eval_global_; CompilationCacheEval eval_contextual_; CompilationCacheRegExp reg_exp_; CompilationSubCache* subcaches_[kSubCacheCount]; // Current enable state of the compilation cache. bool enabled_; friend class Isolate; DISALLOW_COPY_AND_ASSIGN(CompilationCache); }; } } // namespace v8::internal #endif // V8_COMPILATION_CACHE_H_