Use a dictionary-mode code cache on the map rather than a dual system.

src/ic/mips64/ic-mips64.cc

Index: src/ic/mips64/ic-mips64.cc
diff --git a/src/ic/mips64/ic-mips64.cc b/src/ic/mips64/ic-mips64.cc
index f46c9dcb26b9783adb66444cc29f70ea3e470368..03e9d090f8172de569e0be6c26fe36008ee5f410 100644
--- a/src/ic/mips64/ic-mips64.cc
+++ b/src/ic/mips64/ic-mips64.cc
@@ -418,8 +418,8 @@ void KeyedLoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   __ LoadRoot(vector, Heap::kDummyVectorRootIndex);
   __ li(slot, Operand(Smi::FromInt(slot_index)));
 
-  Code::Flags flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::LOAD_IC));
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::LOAD_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::LOAD_IC, flags,
                                                receiver, key, a4, a5, a6, t1);
   // Cache miss.
@@ -667,8 +667,8 @@ void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
   __ LoadRoot(vector, Heap::kDummyVectorRootIndex);
   __ li(slot, Operand(Smi::FromInt(slot_index)));
 
-  Code::Flags flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::STORE_IC));
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::STORE_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::STORE_IC, flags,
                                                receiver, key, a5, a6, a7, t0);
   // Cache miss.
@@ -741,8 +741,8 @@ void StoreIC::GenerateMegamorphic(MacroAssembler* masm) {
   DCHECK(StoreDescriptor::ValueRegister().is(a0));
 
   // Get the receiver from the stack and probe the stub cache.
-  Code::Flags flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::STORE_IC));
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::STORE_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::STORE_IC, flags,
                                                receiver, name, a3, a4, a5, a6);