Revert change 4401.

Review URL: http://codereview.chromium.org/1589035

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4416 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index 62b0373..bbffef2 100644 (file)
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -1389,36 +1389,6 @@ Object* StoreStubCompiler::CompileStoreGlobal(GlobalObject* object,
 }
 
 
-Object* LoadStubCompiler::CompileLoadNonexistent(JSObject* object) {
-  // ----------- S t a t e -------------
-  //  -- r2    : name
-  //  -- lr    : return address
-  //  -- [sp]  : receiver
-  // -----------------------------------
-  Label miss;
-
-  // Load receiver.
-  __ ldr(r0, MemOperand(sp, 0));
-
-  // Check the maps of the full prototype chain.
-  JSObject* last = object;
-  while (last->GetPrototype() != Heap::null_value()) {
-    last = JSObject::cast(last->GetPrototype());
-  }
-  CheckPrototypes(object, r0, last, r3, r1, Heap::empty_string(), &miss);
-
-  // Return undefined if maps of the full prototype chain is still the same.
-  __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-  __ Ret();
-
-  __ bind(&miss);
-  GenerateLoadMiss(masm(), Code::LOAD_IC);
-
-  // Return the generated code.
-  return GetCode(NONEXISTENT, Heap::empty_string());
-}
-
-
 Object* LoadStubCompiler::CompileLoadField(JSObject* object,
                                            JSObject* holder,
                                            int index,

diff --git a/src/globals.h b/src/globals.h
index 410cb3f..3d48e2d 100644 (file)
--- a/src/globals.h
+++ b/src/globals.h
@@ -428,11 +428,7 @@ enum PropertyType {
   CONSTANT_TRANSITION = 6,  // only in fast mode
   NULL_DESCRIPTOR     = 7,  // only in fast mode
   // All properties before MAP_TRANSITION are real.
-  FIRST_PHANTOM_PROPERTY_TYPE = MAP_TRANSITION,
-  // There are no IC stubs for NULL_DESCRIPTORS. Therefore,
-  // NULL_DESCRIPTOR can be used as the type flag for IC stubs for
-  // nonexistent properties.
-  NONEXISTENT = NULL_DESCRIPTOR
+  FIRST_PHANTOM_PROPERTY_TYPE = MAP_TRANSITION
 };
 
 

diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc
index 396a5a3..315600b 100644 (file)
--- a/src/ia32/stub-cache-ia32.cc
+++ b/src/ia32/stub-cache-ia32.cc
@@ -1948,32 +1948,6 @@ Object* KeyedStoreStubCompiler::CompileStoreField(JSObject* object,
 }
 
 
-Object* LoadStubCompiler::CompileLoadNonexistent(JSObject* object) {
-  // ----------- S t a t e -------------
-  //  -- eax    : receiver
-  //  -- ecx    : name
-  //  -- esp[0] : return address
-  // -----------------------------------
-  Label miss;
-
-  // Check the maps of the full prototype chain.
-  JSObject* last = object;
-  while (last->GetPrototype() != Heap::null_value()) {
-    last = JSObject::cast(last->GetPrototype());
-  }
-  CheckPrototypes(object, eax, last, ebx, edx, Heap::empty_string(), &miss);
-
-  // Return undefined if maps of the full prototype chain is still the same.
-  __ mov(eax, Factory::undefined_value());
-  __ ret(0);
-
-  __ bind(&miss);
-  GenerateLoadMiss(masm(), Code::LOAD_IC);
-
-  // Return the generated code.
-  return GetCode(NONEXISTENT, Heap::empty_string());
-}
-
 
 Object* LoadStubCompiler::CompileLoadField(JSObject* object,
                                            JSObject* holder,

diff --git a/src/ic.cc b/src/ic.cc
index 410699c..b9ca00f 100644 (file)
--- a/src/ic.cc
+++ b/src/ic.cc
@@ -694,8 +694,8 @@ void LoadIC::UpdateCaches(LookupResult* lookup,
                           State state,
                           Handle<Object> object,
                           Handle<String> name) {
-  // Bail out if the result is not cachable.
-  if (!lookup->IsCacheable()) return;
+  // Bail out if we didn't find a result.
+  if (!lookup->IsProperty() || !lookup->IsCacheable()) return;
 
   // Loading properties from values is not common, so don't try to
   // deal with non-JS objects here.
@@ -709,9 +709,6 @@ void LoadIC::UpdateCaches(LookupResult* lookup,
     // Set the target to the pre monomorphic stub to delay
     // setting the monomorphic state.
     code = pre_monomorphic_stub();
-  } else if (!lookup->IsProperty()) {
-    // Nonexistent property. The result is undefined.
-    code = StubCache::ComputeLoadNonexistent(*name, *receiver);
   } else {
     // Compute monomorphic stub.
     switch (lookup->type()) {

diff --git a/src/stub-cache.cc b/src/stub-cache.cc
index d77dc25..95877fb 100644 (file)
--- a/src/stub-cache.cc
+++ b/src/stub-cache.cc
@@ -93,28 +93,6 @@ Code* StubCache::Set(String* name, Map* map, Code* code) {
 }
 
 
-Object* StubCache::ComputeLoadNonexistent(String* name, JSObject* receiver) {
-  // The code stub for loading nonexistent properties can be reused
-  // for all names, so we use the empty_string as the name in the map
-  // code cache.
-  Code::Flags flags =
-      Code::ComputeMonomorphicFlags(Code::LOAD_IC, NONEXISTENT);
-  Object* code = receiver->map()->FindInCodeCache(Heap::empty_string(), flags);
-  if (code->IsUndefined()) {
-    LoadStubCompiler compiler;
-    code = compiler.CompileLoadNonexistent(receiver);
-    if (code->IsFailure()) return code;
-    PROFILE(CodeCreateEvent(Logger::LOAD_IC_TAG,
-                            Code::cast(code),
-                            Heap::empty_string()));
-    Object* result = receiver->map()->UpdateCodeCache(Heap::empty_string(),
-                                                      Code::cast(code));
-    if (result->IsFailure()) return result;
-  }
-  return Set(name, receiver->map(), Code::cast(code));
-}
-
-
 Object* StubCache::ComputeLoadField(String* name,
                                     JSObject* receiver,
                                     JSObject* holder,

diff --git a/src/stub-cache.h b/src/stub-cache.h
index 8a68977..0ca37e7 100644 (file)
--- a/src/stub-cache.h
+++ b/src/stub-cache.h
@@ -56,8 +56,6 @@ class StubCache : public AllStatic {
 
   // Computes the right stub matching. Inserts the result in the
   // cache before returning.  This might compile a stub if needed.
-  static Object* ComputeLoadNonexistent(String* name, JSObject* receiver);
-
   static Object* ComputeLoadField(String* name,
                                   JSObject* receiver,
                                   JSObject* holder,
@@ -463,23 +461,18 @@ class StubCompiler BASE_EMBEDDED {
 
 class LoadStubCompiler: public StubCompiler {
  public:
-  Object* CompileLoadNonexistent(JSObject* object);
-
   Object* CompileLoadField(JSObject* object,
                            JSObject* holder,
                            int index,
                            String* name);
-
   Object* CompileLoadCallback(String* name,
                               JSObject* object,
                               JSObject* holder,
                               AccessorInfo* callback);
-
   Object* CompileLoadConstant(JSObject* object,
                               JSObject* holder,
                               Object* value,
                               String* name);
-
   Object* CompileLoadInterceptor(JSObject* object,
                                  JSObject* holder,
                                  String* name);
@@ -501,21 +494,17 @@ class KeyedLoadStubCompiler: public StubCompiler {
                            JSObject* object,
                            JSObject* holder,
                            int index);
-
   Object* CompileLoadCallback(String* name,
                               JSObject* object,
                               JSObject* holder,
                               AccessorInfo* callback);
-
   Object* CompileLoadConstant(String* name,
                               JSObject* object,
                               JSObject* holder,
                               Object* value);
-
   Object* CompileLoadInterceptor(JSObject* object,
                                  JSObject* holder,
                                  String* name);
-
   Object* CompileLoadArrayLength(String* name);
   Object* CompileLoadStringLength(String* name);
   Object* CompileLoadFunctionPrototype(String* name);

diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index cd9a86d..03b21a5 100644 (file)
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -1144,36 +1144,6 @@ Object* LoadStubCompiler::CompileLoadConstant(JSObject* object,
 }
 
 
-Object* LoadStubCompiler::CompileLoadNonexistent(JSObject* object) {
-  // ----------- S t a t e -------------
-  //  -- rcx    : name
-  //  -- rsp[0] : return address
-  //  -- rsp[8] : receiver
-  // -----------------------------------
-  Label miss;
-
-  // Load receiver.
-  __ movq(rax, Operand(rsp, kPointerSize));
-
-  // Check the maps of the full prototype chain.
-  JSObject* last = object;
-  while (last->GetPrototype() != Heap::null_value()) {
-    last = JSObject::cast(last->GetPrototype());
-  }
-  CheckPrototypes(object, rax, last, rbx, rdx, Heap::empty_string(), &miss);
-
-  // Return undefined if maps of the full prototype chain is still the same.
-  __ LoadRoot(rax, Heap::kUndefinedValueRootIndex);
-  __ ret(0);
-
-  __ bind(&miss);
-  GenerateLoadMiss(masm(), Code::LOAD_IC);
-
-  // Return the generated code.
-  return GetCode(NONEXISTENT, Heap::empty_string());
-}
-
-
 Object* LoadStubCompiler::CompileLoadField(JSObject* object,
                                            JSObject* holder,
                                            int index,