Add generations to the compilation cache for eval and regexp

src/compilation-cache.h

 // Copyright 2008 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
@@ skipping 16 matching lines @@
 
 #ifndef V8_COMPILATION_CACHE_H_
 #define V8_COMPILATION_CACHE_H_
 
 namespace v8 {
 namespace internal {
 
 
 // The compilation cache keeps function boilerplates for compiled
 // scripts and evals. The boilerplates are looked up using the source
-// string as the key.
+// string as the key. For regular expressions the compilation data is cached.
 class CompilationCache {
  public:
-  // The same source code string has different compiled code for
-  // scripts and evals. Internally, we use separate caches to avoid
-  // getting the wrong kind of entry when looking up.
-  enum Entry {
-    EVAL_GLOBAL,
-    EVAL_CONTEXTUAL,
-    REGEXP,
-    SCRIPT,
-    LAST_ENTRY = SCRIPT
-  };
-
   // Finds the script function boilerplate 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.
   static Handle<JSFunction> LookupScript(Handle<String> source,
                                          Handle<Object> name,
                                          int line_offset,
                                          int column_offset);
 
   // Finds the function boilerplate 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.
   static Handle<JSFunction> LookupEval(Handle<String> source,
                                        Handle<Context> context,
-                                       Entry entry);
+                                       bool is_global);
 
   // Returns the regexp data associated with the given regexp if it
   // is in cache, otherwise an empty handle.
   static Handle<FixedArray> LookupRegExp(Handle<String> source,
                                          JSRegExp::Flags flags);
 
   // Associate the (source, kind) pair to the boilerplate. This may
   // overwrite an existing mapping.
   static void PutScript(Handle<String> source,
                         Handle<JSFunction> boilerplate);
 
   // Associate the (source, context->closure()->shared(), kind) triple
   // with the boilerplate. This may overwrite an existing mapping.
   static void PutEval(Handle<String> source,
                       Handle<Context> context,
-                      Entry entry,
+                      bool is_global,
                       Handle<JSFunction> boilerplate);
 
   // Associate the (source, flags) pair to the given regexp data.
   // This may overwrite an existing mapping.
   static void PutRegExp(Handle<String> source,
                         JSRegExp::Flags flags,
                         Handle<FixedArray> data);
 
   // Clear the cache - also used to initialize the cache at startup.
   static void Clear();
 
   // GC support.
   static void Iterate(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.
   static void MarkCompactPrologue();
 
   // Enable/disable compilation cache. Used by debugger to disable compilation
   // cache during debugging to make sure new scripts are always compiled.
   static void Enable();
   static void Disable();
 };
 
 
+// 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. As the same source code string has
+// different compiled code for scripts and evals. Internally, we use separate
+// sub-caches to avoid getting the wrong kind of entry when looking up.
+class CompilationSubCache {
+ public:
+  explicit CompilationSubCache(int generations): generations_(generations) {
+    // tables_ = new Object*[generations];
+    tables_ = NewArray<Object*>(generations);
+  }
+  virtual ~CompilationSubCache() {
+    DeleteArray(tables_);
+  }
+
+  // Get the compilation cache tables for a specific generation.
+  Handle<CompilationCacheTable> GetTable(int generation);
+
+  // Age the sub-cache by evicting the oldest generation and creating a new
+  // young generation.
+  void Age();
+
+  // GC support.
+  void Iterate(ObjectVisitor* v);
+
+  // Clear this sub-cache evicting all its content.
+  void Clear();
+
+  // Number of generations in this sub-cache.
+  inline int generations() { return generations_; }
+
+ private:
+  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:
+  explicit CompilationCacheScript(int generations)
+      : CompilationSubCache(generations) { }
+
+  Handle<JSFunction> Lookup(Handle<String> source,
+                            Handle<Object> name,
+                            int line_offset,
+                            int column_offset);
+  void Put(Handle<String> source, Handle<JSFunction> boilerplate);
+
+ private:
+  bool HasOrigin(Handle<JSFunction> boilerplate,
+                 Handle<Object> name,
+                 int line_offset,
+                 int column_offset);
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheScript);
+};
+
+
+// Sub-cache for eval scripts.
+class CompilationCacheEval: public CompilationSubCache {
+ public:
+  explicit CompilationCacheEval(int generations)
+      : CompilationSubCache(generations) { }
+
+  Handle<JSFunction> Lookup(Handle<String> source, Handle<Context> context);
+
+  void Put(Handle<String> source,
+           Handle<Context> context,
+           Handle<JSFunction> boilerplate);
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheEval);
+};
+
+
+// Sub-cache for regular expressions.
+class CompilationCacheRegExp: public CompilationSubCache {
+ public:
+  explicit CompilationCacheRegExp(int generations)
+      : CompilationSubCache(generations) { }
+
+  Handle<FixedArray> Lookup(Handle<String> source, JSRegExp::Flags flags);
+
+  void Put(Handle<String> source,
+           JSRegExp::Flags flags,
+           Handle<FixedArray> data);
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheRegExp);
+};
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_COMPILATION_CACHE_H_