[stubs] Migrate ToLengthStub to TurboFan.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index d4ccd91c872dfa39e871139f15b54473608bb827..1e12789ce602b6989a3f3354f4c21a0488a2d148 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -2599,25 +2599,6 @@ void StringToNumberStub::Generate(MacroAssembler* masm) {
   __ TailCallRuntime(Runtime::kStringToNumber);
 }
 
-void ToLengthStub::Generate(MacroAssembler* masm) {
-  // The ToLength stub takes on argument in rax.
-  Label not_smi, positive_smi;
-  __ JumpIfNotSmi(rax, &not_smi, Label::kNear);
-  STATIC_ASSERT(kSmiTag == 0);
-  __ testp(rax, rax);
-  __ j(greater_equal, &positive_smi, Label::kNear);
-  __ xorl(rax, rax);
-  __ bind(&positive_smi);
-  __ Ret();
-  __ bind(&not_smi);
-
-  __ PopReturnAddressTo(rcx);     // Pop return address.
-  __ Push(rax);                   // Push argument.
-  __ PushReturnAddressFrom(rcx);  // Push return address.
-  __ TailCallRuntime(Runtime::kToLength);
-}
-
-
 void ToStringStub::Generate(MacroAssembler* masm) {
   // The ToString stub takes one argument in rax.
   Label is_number;