Track up to 5 stable maps as field type.

src/arm64/stub-cache-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 374 matching lines @@
   ASSERT(!representation.IsNone());
 
   if (details.type() == CONSTANT) {
     Handle<Object> constant(descriptors->GetValue(descriptor), masm->isolate());
     __ LoadObject(scratch1, constant);
     __ Cmp(value_reg, scratch1);
     __ B(ne, miss_label);
   } else if (representation.IsSmi()) {
     __ JumpIfNotSmi(value_reg, miss_label);
   } else if (representation.IsHeapObject()) {
+    __ JumpIfSmi(value_reg, miss_label);
     HeapType* field_type = descriptors->GetFieldType(descriptor);
-    if (field_type->IsClass()) {
-      __ CheckMap(value_reg, scratch1, field_type->AsClass()->Map(),
-                  miss_label, DO_SMI_CHECK);
-    } else {
-      ASSERT(HeapType::Any()->Is(field_type));
-      __ JumpIfSmi(value_reg, miss_label);
+    HeapType::Iterator<Map> it = field_type->Classes();
+    if (!it.Done()) {
+      __ Ldr(scratch1, FieldMemOperand(value_reg, HeapObject::kMapOffset));
+      Label do_store;
+      while (true) {
+        __ CompareMap(scratch1, it.Current());
+        it.Advance();
+        if (it.Done()) {
+          __ B(ne, miss_label);
+          break;
+        }
+        __ B(eq, &do_store);
+      }
+      __ Bind(&do_store);
     }
   } else if (representation.IsDouble()) {
     UseScratchRegisterScope temps(masm);
     DoubleRegister temp_double = temps.AcquireD();
     __ SmiUntagToDouble(temp_double, value_reg, kSpeculativeUntag);
 
     Label do_store;
     __ JumpIfSmi(value_reg, &do_store);
 
     __ CheckMap(value_reg, scratch1, Heap::kHeapNumberMapRootIndex,
@@ skipping 129 matching lines @@
   // Adjust for the number of properties stored in the object. Even in the
   // face of a transition we can use the old map here because the size of the
   // object and the number of in-object properties is not going to change.
   index -= object->map()->inobject_properties();
 
   Representation representation = lookup->representation();
   ASSERT(!representation.IsNone());
   if (representation.IsSmi()) {
     __ JumpIfNotSmi(value_reg, miss_label);
   } else if (representation.IsHeapObject()) {
+    __ JumpIfSmi(value_reg, miss_label);
     HeapType* field_type = lookup->GetFieldType();
-    if (field_type->IsClass()) {
-      __ CheckMap(value_reg, scratch1, field_type->AsClass()->Map(),
-                  miss_label, DO_SMI_CHECK);
-    } else {
-      ASSERT(HeapType::Any()->Is(field_type));
-      __ JumpIfSmi(value_reg, miss_label);
+    HeapType::Iterator<Map> it = field_type->Classes();
+    if (!it.Done()) {
+      __ Ldr(scratch1, FieldMemOperand(value_reg, HeapObject::kMapOffset));
+      Label do_store;
+      while (true) {
+        __ CompareMap(scratch1, it.Current());
+        it.Advance();
+        if (it.Done()) {
+          __ B(ne, miss_label);
+          break;
+        }
+        __ B(eq, &do_store);
+      }
+      __ Bind(&do_store);
     }
   } else if (representation.IsDouble()) {
     UseScratchRegisterScope temps(masm);
     DoubleRegister temp_double = temps.AcquireD();
 
     __ SmiUntagToDouble(temp_double, value_reg, kSpeculativeUntag);
 
     // Load the double storage.
     if (index < 0) {
       int offset = (index * kPointerSize) + object->map()->instance_size();
@@ skipping 931 matching lines @@
 
   // Miss case, call the runtime.
   __ Bind(&miss);
   TailCallBuiltin(masm, Builtins::kKeyedLoadIC_Miss);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64