[turbofan] Simplify lowering of number addition.

src/compiler/simplified-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/compiler/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 721 matching lines @@
           // => Float64Cmp
           VisitFloat64Cmp(node);
           if (lower()) NodeProperties::ChangeOp(node, Float64Op(node));
         }
         break;
       }
       case IrOpcode::kNumberAdd:
       case IrOpcode::kNumberSubtract: {
         // Add and subtract reduce to Int32Add/Sub if the inputs
         // are already integers and all uses are truncating.
-        if (CanLowerToInt32Binop(node, use)) {
+        if (CanLowerToWord32AdditiveBinop(node, use)) {
           // => signed Int32Add/Sub
           VisitInt32Binop(node);
           if (lower()) NodeProperties::ChangeOp(node, Int32Op(node));
-        } else if (CanLowerToUint32Binop(node, use)) {
-          // => unsigned Int32Add/Sub
-          VisitUint32Binop(node);
-          if (lower()) NodeProperties::ChangeOp(node, Uint32Op(node));
-        } else if (CanLowerToWord32AdditiveBinop(node, use)) {
-          // => signed Int32Add/Sub, truncating inputs
-          ProcessTruncateWord32Input(node, 0);
-          ProcessTruncateWord32Input(node, 1);
-          SetOutput(node, kMachInt32);
-          if (lower()) NodeProperties::ChangeOp(node, Int32Op(node));
         } else {
           // => Float64Add/Sub
           VisitFloat64Binop(node);
           if (lower()) NodeProperties::ChangeOp(node, Float64Op(node));
         }
         break;
       }
       case IrOpcode::kNumberMultiply: {
         NumberMatcher right(node->InputAt(1));
         if (right.IsInRange(-1048576, 1048576)) {  // must fit double mantissa.
@@ skipping 903 matching lines @@
   ReplaceEffectUses(node, comparison);
   node->ReplaceInput(0, comparison);
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, machine()->IntLessThanOrEqual());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8