Avoid flushing the icache unnecessarily when updating target addresses in code.

src/ic.h

 // 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.
 
 #ifndef V8_IC_H_
 #define V8_IC_H_
 
 #include "macro-assembler.h"
 
 namespace v8 {
@@ skipping 142 matching lines @@
   Isolate* isolate() const { return isolate_; }
 
   // Get the shared function info of the caller.
   SharedFunctionInfo* GetSharedFunctionInfo() const;
   // Get the code object of the caller.
   Code* GetCode() const;
   // Get the original (non-breakpointed) code object of the caller.
   Code* GetOriginalCode() const;
 
   // Set the call-site target.
-  void set_target(Code* code) {
+  void set_target(Code* code,
+                  ICacheFlushMode icache_flush_mode = FLUSH_ICACHE_IF_NEEDED) {
 #ifdef VERIFY_HEAP
     code->VerifyEmbeddedObjectsDependency();
 #endif
-    SetTargetAtAddress(address(), code, constant_pool());
+    SetTargetAtAddress(address(), code, constant_pool(), icache_flush_mode);
     target_set_ = true;
   }
 
   bool is_target_set() { return target_set_; }
 
 #ifdef DEBUG
   char TransitionMarkFromState(IC::State state);
 
   void TraceIC(const char* type, Handle<Object> name);
 #endif
 
   MaybeHandle<Object> TypeError(const char* type,
                                 Handle<Object> object,
                                 Handle<Object> key);
   MaybeHandle<Object> ReferenceError(const char* type, Handle<String> name);
 
   // Access the target code for the given IC address.
   static inline Code* GetTargetAtAddress(Address address,
                                          ConstantPoolArray* constant_pool);
   static inline void SetTargetAtAddress(Address address,
                                         Code* target,
-                                        ConstantPoolArray* constant_pool);
+                                        ConstantPoolArray* constant_pool,
+                                        ICacheFlushMode icache_flush_mode =
+                                            FLUSH_ICACHE_IF_NEEDED);
   static void PostPatching(Address address, Code* target, Code* old_target);
 
   // Compute the handler either by compiling or by retrieving a cached version.
   Handle<Code> ComputeHandler(LookupResult* lookup,
                               Handle<Object> object,
                               Handle<String> name,
                               Handle<Object> value = Handle<Code>::null());
   virtual Handle<Code> CompileHandler(LookupResult* lookup,
                                       Handle<Object> object,
                                       Handle<String> name,
@@ skipping 248 matching lines @@
 
   static Handle<Code> initialize_stub(Isolate* isolate,
                                       ExtraICState extra_state);
 
   MUST_USE_RESULT MaybeHandle<Object> Load(Handle<Object> object,
                                            Handle<String> name);
 
  protected:
   virtual Code::Kind kind() const { return Code::LOAD_IC; }
 
-  void set_target(Code* code) {
+  void set_target(Code* code,
+                  ICacheFlushMode icache_flush_mode = FLUSH_ICACHE_IF_NEEDED) {
     // The contextual mode must be preserved across IC patching.
     ASSERT(GetContextualMode(code->extra_ic_state()) ==
            GetContextualMode(target()->extra_ic_state()));
 
-    IC::set_target(code);
+    IC::set_target(code, icache_flush_mode);
   }
 
   virtual Handle<Code> slow_stub() const {
     return isolate()->builtins()->LoadIC_Slow();
   }
 
   virtual Handle<Code> megamorphic_stub();
 
   // Update the inline cache and the global stub cache based on the
   // lookup result.
@@ skipping 173 matching lines @@
                     Handle<JSObject> receiver,
                     Handle<String> name,
                     Handle<Object> value);
   virtual Handle<Code> CompileHandler(LookupResult* lookup,
                                       Handle<Object> object,
                                       Handle<String> name,
                                       Handle<Object> value,
                                       InlineCacheHolderFlag cache_holder);
 
  private:
-  void set_target(Code* code) {
+  void set_target(Code* code,
+                  ICacheFlushMode icache_flush_mode = FLUSH_ICACHE_IF_NEEDED) {
     // Strict mode must be preserved across IC patching.
     ASSERT(GetStrictMode(code->extra_ic_state()) ==
            GetStrictMode(target()->extra_ic_state()));
-    IC::set_target(code);
+    IC::set_target(code, icache_flush_mode);
   }
 
   static void Clear(Isolate* isolate,
                     Address address,
                     Code* target,
                     ConstantPoolArray* constant_pool);
 
   friend class IC;
 };
 
@@ skipping 358 matching lines @@
 DECLARE_RUNTIME_FUNCTION(ElementsTransitionAndStoreIC_Miss);
 DECLARE_RUNTIME_FUNCTION(BinaryOpIC_Miss);
 DECLARE_RUNTIME_FUNCTION(BinaryOpIC_MissWithAllocationSite);
 DECLARE_RUNTIME_FUNCTION(CompareNilIC_Miss);
 DECLARE_RUNTIME_FUNCTION(ToBooleanIC_Miss);
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_IC_H_