[turbofan] Add Int32AddWithOverflow machine operator.

src/compiler/instruction-selector-impl.h

 // 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.
 
 #ifndef V8_COMPILER_INSTRUCTION_SELECTOR_IMPL_H_
 #define V8_COMPILER_INSTRUCTION_SELECTOR_IMPL_H_
 
 #include "src/compiler/instruction.h"
 #include "src/compiler/instruction-selector.h"
 #include "src/compiler/linkage.h"
@@ skipping 238 matching lines @@
     ASSERT(IsBranch());
     return false_block_;
   }
 
   void Negate() { condition_ = static_cast<FlagsCondition>(condition_ ^ 1); }
 
   void Commute() {
     switch (condition_) {
       case kEqual:
       case kNotEqual:
+      case kOverflow:
+      case kNotOverflow:
         return;
       case kSignedLessThan:
         condition_ = kSignedGreaterThan;
         return;
       case kSignedGreaterThanOrEqual:
         condition_ = kSignedLessThanOrEqual;
         return;
       case kSignedLessThanOrEqual:
         condition_ = kSignedGreaterThanOrEqual;
         return;
@@ skipping 74 matching lines @@
   int control_count() { return descriptor->CanLazilyDeoptimize() ? 2 : 0; }
 
   int fixed_and_control_count() { return fixed_count + control_count(); }
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_SELECTOR_IMPL_H_