Better support for 'polymorphic' JS and external arrays

src/arm/ic-arm.cc

Index: src/arm/ic-arm.cc
diff --git a/src/arm/ic-arm.cc b/src/arm/ic-arm.cc
index 731c4719e79146ec3a99c3c1e9472f16bba98eb8..8749eea5b247ccc1f1a80562f302112f5653cc2a 100644
--- a/src/arm/ic-arm.cc
+++ b/src/arm/ic-arm.cc
@@ -868,10 +868,7 @@ void LoadIC::GenerateMiss(MacroAssembler* masm) {
 }
 
 
-Object* KeyedLoadIC_Miss(Arguments args);
-
-
-void KeyedLoadIC::GenerateMiss(MacroAssembler* masm) {
+void KeyedLoadIC::GenerateMiss(MacroAssembler* masm, bool force_generic) {
   // ---------- S t a t e --------------
   //  -- lr     : return address
   //  -- r0     : key
@@ -883,8 +880,11 @@ void KeyedLoadIC::GenerateMiss(MacroAssembler* masm) {
 
   __ Push(r1, r0);
 
-  ExternalReference ref =
-      ExternalReference(IC_Utility(kKeyedLoadIC_Miss), isolate);
+  // Perform tail call to the entry.
+  ExternalReference ref = force_generic
+      ? ExternalReference(IC_Utility(kKeyedLoadIC_MissForceGeneric), isolate)
+      : ExternalReference(IC_Utility(kKeyedLoadIC_Miss), isolate);
+
   __ TailCallExternalReference(ref, 2, 1);
 }
 
@@ -1075,7 +1075,7 @@ void KeyedLoadIC::GenerateString(MacroAssembler* masm) {
   char_at_generator.GenerateSlow(masm, call_helper);
 
   __ bind(&miss);
-  GenerateMiss(masm);
+  GenerateMiss(masm, false);
 }
 
 
@@ -1115,11 +1115,30 @@ void KeyedLoadIC::GenerateIndexedInterceptor(MacroAssembler* masm) {
       1);
 
   __ bind(&slow);
-  GenerateMiss(masm);
+  GenerateMiss(masm, false);
+}
+
+
+void KeyedStoreIC::GenerateMiss(MacroAssembler* masm, bool force_generic) {
+  // ---------- S t a t e --------------
+  //  -- r0     : value
+  //  -- r1     : key
+  //  -- r2     : receiver
+  //  -- lr     : return address
+  // -----------------------------------
+
+  // Push receiver, key and value for runtime call.
+  __ Push(r2, r1, r0);
+
+  ExternalReference ref = force_generic
+      ? ExternalReference(IC_Utility(kKeyedStoreIC_MissForceGeneric),
+                          masm->isolate())
+      : ExternalReference(IC_Utility(kKeyedStoreIC_Miss), masm->isolate());
+  __ TailCallExternalReference(ref, 3, 1);
 }
 
 
-void KeyedStoreIC::GenerateMiss(MacroAssembler* masm) {
+void KeyedStoreIC::GenerateSlow(MacroAssembler* masm) {
   // ---------- S t a t e --------------
   //  -- r0     : value
   //  -- r1     : key
@@ -1130,8 +1149,10 @@ void KeyedStoreIC::GenerateMiss(MacroAssembler* masm) {
   // Push receiver, key and value for runtime call.
   __ Push(r2, r1, r0);
 
+  // The slow case calls into the runtime to complete the store without causing
+  // an IC miss that would otherwise cause a transition to the generic stub.
   ExternalReference ref =
-      ExternalReference(IC_Utility(kKeyedStoreIC_Miss), masm->isolate());
+      ExternalReference(IC_Utility(kKeyedStoreIC_Slow), masm->isolate());
   __ TailCallExternalReference(ref, 3, 1);
 }