[builtins] Migrate StringToNumber to TurboFan builtin.

src/builtins/ppc/builtins-ppc.cc

Index: src/builtins/ppc/builtins-ppc.cc
diff --git a/src/builtins/ppc/builtins-ppc.cc b/src/builtins/ppc/builtins-ppc.cc
index cd0a4d96edb92b3b7ffb4a85bad3a9dfeb21e8ce..688247283dceb415935a008f8403429d3d998d54 100644
--- a/src/builtins/ppc/builtins-ppc.cc
+++ b/src/builtins/ppc/builtins-ppc.cc
@@ -2834,31 +2834,6 @@ void Builtins::Generate_Abort(MacroAssembler* masm) {
 }
 
 // static
-void Builtins::Generate_StringToNumber(MacroAssembler* masm) {
-  // The StringToNumber stub takes one argument in r3.
-  __ AssertString(r3);
-
-  // Check if string has a cached array index.
-  Label runtime;
-  __ lwz(r5, FieldMemOperand(r3, String::kHashFieldOffset));
-  __ And(r0, r5, Operand(String::kContainsCachedArrayIndexMask), SetRC);
-  __ bne(&runtime, cr0);
-  __ IndexFromHash(r5, r3);
-  __ blr();
-
-  __ bind(&runtime);
-  {
-    FrameScope frame(masm, StackFrame::INTERNAL);
-    // Push argument.
-    __ push(r3);
-    // We cannot use a tail call here because this builtin can also be called
-    // from wasm.
-    __ CallRuntime(Runtime::kStringToNumber);
-  }
-  __ Ret();
-}
-
-// static
 void Builtins::Generate_ToNumber(MacroAssembler* masm) {
   // The ToNumber stub takes one argument in r3.
   STATIC_ASSERT(kSmiTag == 0);