[stubs] replaced ToString MacroAssembler Stub with CodeStubAssembler builtin

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 3754ea4a3d931024917baad6dc60554b9c91f928..3b497561c3cc298858b424dfdcd25862954346b9 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -2924,37 +2924,6 @@ void SubStringStub::Generate(MacroAssembler* masm) {
   generator.SkipSlow(masm, &runtime);
 }
 
-void ToStringStub::Generate(MacroAssembler* masm) {
-  // The ToString stub takes one argument in x0.
-  Label is_number;
-  __ JumpIfSmi(x0, &is_number);
-
-  Label not_string;
-  __ JumpIfObjectType(x0, x1, x1, FIRST_NONSTRING_TYPE, &not_string, hs);
-  // x0: receiver
-  // x1: receiver instance type
-  __ Ret();
-  __ Bind(&not_string);
-
-  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::kToString);
-}
-
 
 void StringHelper::GenerateFlatOneByteStringEquals(
     MacroAssembler* masm, Register left, Register right, Register scratch1,