[ic] Split megamorphic stub cache in two caches (for loads and for stores).

src/arm64/code-stubs-arm64.cc

Index: src/arm64/code-stubs-arm64.cc
diff --git a/src/arm64/code-stubs-arm64.cc b/src/arm64/code-stubs-arm64.cc
index 7f334f4e17f6c30545abd11130d3f96875551f44..e128a29a901ba62083ce25139909a052baad83c7 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -3464,11 +3464,8 @@ void LoadICStub::GenerateImpl(MacroAssembler* masm, bool in_frame) {
 
   __ Bind(&not_array);
   __ JumpIfNotRoot(feedback, Heap::kmegamorphic_symbolRootIndex, &miss);
-  Code::Flags code_flags =
-      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::LOAD_IC));
-  masm->isolate()->stub_cache()->GenerateProbe(masm, Code::LOAD_IC, code_flags,
-                                               receiver, name, feedback,
-                                               receiver_map, scratch1, x7);
+  masm->isolate()->load_stub_cache()->GenerateProbe(
+      masm, receiver, name, feedback, receiver_map, scratch1, x7);
 
   __ Bind(&miss);
   LoadIC::GenerateMiss(masm);
@@ -3600,11 +3597,8 @@ void VectorStoreICStub::GenerateImpl(MacroAssembler* masm, bool in_frame) {
 
   __ Bind(&not_array);
   __ JumpIfNotRoot(feedback, Heap::kmegamorphic_symbolRootIndex, &miss);
-  Code::Flags code_flags =
-      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::STORE_IC));
-  masm->isolate()->stub_cache()->GenerateProbe(masm, Code::STORE_IC, code_flags,
-                                               receiver, key, feedback,
-                                               receiver_map, scratch1, x8);
+  masm->isolate()->store_stub_cache()->GenerateProbe(
+      masm, receiver, key, feedback, receiver_map, scratch1, x8);
 
   __ Bind(&miss);
   StoreIC::GenerateMiss(masm);