[turbofan] Introduce dedicated NumberConvertHoleNaN simplified operator.

src/compiler/js-typed-lowering.cc

 // Copyright 2014 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.
 
 #include "src/code-factory.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-typed-lowering.h"
 #include "src/compiler/linkage.h"
@@ skipping 787 matching lines @@
         NodeProperties::SetType(input, input_type);
       }
     }
     ReplaceWithValue(node, input);
     return Replace(input);
   }
   return NoChange();
 }
 
 Reduction JSTypedLowering::ReduceJSToNumberInput(Node* input) {
-  // Check for ToNumber truncation of signaling NaN to undefined mapping.
-  if (input->opcode() == IrOpcode::kSelect) {
-    Node* check = NodeProperties::GetValueInput(input, 0);
-    Node* vtrue = NodeProperties::GetValueInput(input, 1);
-    Type* vtrue_type = NodeProperties::GetType(vtrue);
-    Node* vfalse = NodeProperties::GetValueInput(input, 2);
-    Type* vfalse_type = NodeProperties::GetType(vfalse);
-    if (vtrue_type->Is(Type::Undefined()) && vfalse_type->Is(Type::Number())) {
-      if (check->opcode() == IrOpcode::kNumberIsHoleNaN &&
-          check->InputAt(0) == vfalse) {
-        // JSToNumber(Select(NumberIsHoleNaN(x), y:undefined, x:number)) => x
-        return Replace(vfalse);
-      }
-    }
-  }
   // Try constant-folding of JSToNumber with constant inputs.
   Type* input_type = NodeProperties::GetType(input);
   if (input_type->IsConstant()) {
     Handle<Object> input_value = input_type->AsConstant()->Value();
     if (input_value->IsString()) {
       return Replace(jsgraph()->Constant(
           String::ToNumber(Handle<String>::cast(input_value))));
     } else if (input_value->IsOddball()) {
       return Replace(jsgraph()->Constant(
           Oddball::ToNumber(Handle<Oddball>::cast(input_value))));
@@ skipping 1129 matching lines @@
 }
 
 
 CompilationDependencies* JSTypedLowering::dependencies() const {
   return dependencies_;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8