[stubs] Introduce ToNameStub to implement %_ToName.

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 a9b647ca80095acce040ac6a3823dc16dae6ea48..d34a0504357cc79daeb185a2fb9fccd458faa372 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -3878,6 +3878,39 @@ void ToStringStub::Generate(MacroAssembler* masm) {
 }
 
 
+void ToNameStub::Generate(MacroAssembler* masm) {
+  // The ToName stub takes one argument in x0.
+  Label is_number;
+  __ JumpIfSmi(x0, &is_number);
+
+  Label not_name;
+  STATIC_ASSERT(FIRST_NAME_TYPE == FIRST_TYPE);
+  __ JumpIfObjectType(x0, x1, x1, LAST_NAME_TYPE, &not_name, hi);
+  // x0: receiver
+  // x1: receiver instance type
+  __ Ret();
+  __ Bind(&not_name);
+
+  Label not_heap_number;
+  __ Cmp(x1, HEAP_NUMBER_TYPE);
+  __ B(ne, &not_heap_number);
+  __ Bind(&is_number);
+  NumberToStringStub stub(isolate());
+  __ TailCallStub(&stub);
+  __ Bind(&not_heap_number);
+
+  Label not_oddball;
+  __ Cmp(x1, ODDBALL_TYPE);
+  __ B(ne, &not_oddball);
+  __ Ldr(x0, FieldMemOperand(x0, Oddball::kToStringOffset));
+  __ Ret();
+  __ Bind(&not_oddball);
+
+  __ Push(x0);  // Push argument.
+  __ TailCallRuntime(Runtime::kToName);
+}
+
+
 void StringHelper::GenerateFlatOneByteStringEquals(
     MacroAssembler* masm, Register left, Register right, Register scratch1,
     Register scratch2, Register scratch3) {