Store transitioned JSArray maps in global context

src/ia32/macro-assembler-ia32.cc

Index: src/ia32/macro-assembler-ia32.cc
diff --git a/src/ia32/macro-assembler-ia32.cc b/src/ia32/macro-assembler-ia32.cc
index d0d9e19c9013344990304438a152577199e80995..505fac649dd60e32dc3245d903538ddff6e15ec9 100644
--- a/src/ia32/macro-assembler-ia32.cc
+++ b/src/ia32/macro-assembler-ia32.cc
@@ -2168,6 +2168,32 @@ void MacroAssembler::LoadContext(Register dst, int context_chain_length) {
 }
 
 
+void MacroAssembler::LoadGlobalInitialConstructedArrayMap(
+    Register function_in, Register scratch, Register map_out) {
+  ASSERT(!function_in.is(map_out));
+  Label done;
+  mov(map_out, FieldOperand(function_in,
+                            JSFunction::kPrototypeOrInitialMapOffset));
+  if (!FLAG_smi_only_arrays) {
+    // Load the global or builtins object from the current context.
+    mov(scratch, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
+    mov(scratch, FieldOperand(scratch, GlobalObject::kGlobalContextOffset));
+
+    // Check that the function's map is same as the cached map.
+    cmp(map_out,
+        Operand(scratch,
+                Context::SlotOffset(Context::SMI_JS_ARRAY_MAP_INDEX)));
+    j(not_equal, &done);
+
+    // Use the cached transitioned map.
+    mov(map_out,
+        Operand(scratch,
+                Context::SlotOffset(Context::OBJECT_JS_ARRAY_MAP_INDEX)));
+  }
+  bind(&done);
+}
+
+
 void MacroAssembler::LoadGlobalFunction(int index, Register function) {
   // Load the global or builtins object from the current context.
   mov(function, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));