[builtins] Migrate StringToNumber to TurboFan builtin.

src/builtins/mips/builtins-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 2810 matching lines @@
   // ----------- S t a t e -------------
   //  -- a0 : message_id as Smi
   //  -- ra : return address
   // -----------------------------------
   __ Push(a0);
   __ Move(cp, Smi::FromInt(0));
   __ TailCallRuntime(Runtime::kAbort);
 }
 
 // static
-void Builtins::Generate_StringToNumber(MacroAssembler* masm) {
-  // The StringToNumber stub takes on argument in a0.
-  __ AssertString(a0);
-
-  // Check if string has a cached array index.
-  Label runtime;
-  __ lw(a2, FieldMemOperand(a0, String::kHashFieldOffset));
-  __ And(at, a2, Operand(String::kContainsCachedArrayIndexMask));
-  __ Branch(&runtime, ne, at, Operand(zero_reg));
-  __ IndexFromHash(a2, v0);
-  __ Ret();
-
-  __ bind(&runtime);
-  {
-    FrameScope frame(masm, StackFrame::INTERNAL);
-    // Push argument.
-    __ Push(a0);
-    // 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 a0.
   Label not_smi;
   __ JumpIfNotSmi(a0, &not_smi);
   __ Ret(USE_DELAY_SLOT);
   __ mov(v0, a0);
   __ bind(&not_smi);
 
   Label not_heap_number;
   __ GetObjectType(a0, a1, a1);
@@ skipping 137 matching lines @@
     __ break_(0xCC);
   }
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS