Track elements_kind transitions in KeyedStoreICs.

src/ia32/stub-cache-ia32.cc

Index: src/ia32/stub-cache-ia32.cc
diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc
index 9b8f096621b5b2710f5c4f18c726e1ba0f139df4..277f97b0c8b8d74da30348325da635d8f208b3a1 100644
--- a/src/ia32/stub-cache-ia32.cc
+++ b/src/ia32/stub-cache-ia32.cc
@@ -2759,6 +2759,62 @@ MaybeObject* KeyedStoreStubCompiler::CompileStoreElement(Map* receiver_map) {
 }
 
 
+MaybeObject* KeyedStoreStubCompiler::CompileStoreElementWithTransition(
+    Map* transitioned_map,
+    Map* untransitioned_map_1,
+    Map* untransitioned_map_2) {
+  // ----------- S t a t e -------------
+  //  -- eax    : value
+  //  -- ecx    : key
+  //  -- edx    : receiver
+  //  -- esp[0] : return address
+  // -----------------------------------
+
+  // The order of map occurrences in the generated code below is important.
+  // Both IC code and Crankshaft rely on |transitioned_map| being the first
+  // map in the stub.
+
+  Code* notransition_stub;
+  ElementsKind elements_kind = transitioned_map->elements_kind();
+  bool is_jsarray = transitioned_map->instance_type() == JS_ARRAY_TYPE;
+  MaybeObject* maybe_stub =
+      KeyedStoreElementStub(is_jsarray, elements_kind).TryGetCode();
+  if (!maybe_stub->To(&notransition_stub)) return maybe_stub;
+
+  Label just_store, miss;
+  __ JumpIfSmi(edx, &miss, Label::kNear);
+  __ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
+  // ebx: receiver->map().
+  __ cmp(ebx, Handle<Map>(transitioned_map));
+  __ j(equal, &just_store);
+  ASSERT_NE(untransitioned_map_1, NULL);
+  __ cmp(ebx, Handle<Map>(untransitioned_map_1));
+  // TODO(jkummerow): When we have specialized code to do the transition,
+  // call that code here, then jump to just_store when the call returns.
+  // <temporary: just use the generic stub>
+  Code* generic_stub = (strict_mode_ == kStrictMode)
+      ? isolate()->builtins()->builtin(Builtins::kKeyedStoreIC_Generic_Strict)
+      : isolate()->builtins()->builtin(Builtins::kKeyedStoreIC_Generic);
+  __ j(equal, Handle<Code>(generic_stub));
+  // </temporary>
+  if (untransitioned_map_2 != NULL) {
+    __ cmp(ebx, Handle<Map>(untransitioned_map_2));
+    // <temporary: see above, same here>
+    __ j(equal, Handle<Code>(generic_stub));
+    // </temporary>
+  }
+  __ bind(&miss);
+  Handle<Code> ic = isolate()->builtins()->KeyedStoreIC_Miss();
+  __ jmp(ic, RelocInfo::CODE_TARGET);
+
+  __ bind(&just_store);
+  __ jmp(Handle<Code>(notransition_stub), RelocInfo::CODE_TARGET);
+
+  // Return the generated code.
+  return GetCode(NORMAL, NULL, MEGAMORPHIC);
+}
+
+
 MaybeObject* KeyedStoreStubCompiler::CompileStoreMegamorphic(
     MapList* receiver_maps,
     CodeList* handler_ics) {
@@ -3910,7 +3966,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastElement(
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
-  Label miss_force_generic;
+  Label miss_force_generic, transition_elements_kind;
 
   // This stub is meant to be tail-jumped to, the receiver must already
   // have been verified by the caller to not be a smi.
@@ -3935,7 +3991,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastElement(
   }
 
   if (elements_kind == FAST_SMI_ONLY_ELEMENTS) {
-    __ JumpIfNotSmi(eax, &miss_force_generic);
+    __ JumpIfNotSmi(eax, &transition_elements_kind);
     // ecx is a smi, use times_half_pointer_size instead of
     // times_pointer_size
     __ mov(FieldOperand(edi,
@@ -3965,6 +4021,11 @@ void KeyedStoreStubCompiler::GenerateStoreFastElement(
   Handle<Code> ic_force_generic =
       masm->isolate()->builtins()->KeyedStoreIC_MissForceGeneric();
   __ jmp(ic_force_generic, RelocInfo::CODE_TARGET);
+
+  // Handle transition to other elements kinds without using the generic stub.
+  __ bind(&transition_elements_kind);
+  Handle<Code> ic_miss = masm->isolate()->builtins()->KeyedStoreIC_Miss();
+  __ jmp(ic_miss, RelocInfo::CODE_TARGET);
 }
 
 
@@ -3977,7 +4038,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
-  Label miss_force_generic;
+  Label miss_force_generic, transition_elements_kind;
 
   // This stub is meant to be tail-jumped to, the receiver must already
   // have been verified by the caller to not be a smi.
@@ -4003,7 +4064,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(
                                  ecx,
                                  edx,
                                  xmm0,
-                                 &miss_force_generic,
+                                 &transition_elements_kind,
                                  true);
   __ ret(0);
 
@@ -4012,6 +4073,11 @@ void KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(
   Handle<Code> ic_force_generic =
       masm->isolate()->builtins()->KeyedStoreIC_MissForceGeneric();
   __ jmp(ic_force_generic, RelocInfo::CODE_TARGET);
+
+  // Handle transition to other elements kinds without using the generic stub.
+  __ bind(&transition_elements_kind);
+  Handle<Code> ic_miss = masm->isolate()->builtins()->KeyedStoreIC_Miss();
+  __ jmp(ic_miss, RelocInfo::CODE_TARGET);
 }