[turbofan] Take type into account when determining Word32 phi representation.

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 306 matching lines @@
       // only tagged uses.
       return kRepTagged;
     } else if (upper->Is(Type::Integral32())) {
       // Integer within [-2^31, 2^32[ range.
       if ((use & kRepMask) == kRepFloat64) {
         // only float64 uses.
         return kRepFloat64;
       } else if (upper->Is(Type::Signed32()) || upper->Is(Type::Unsigned32())) {
         // multiple uses, but we are within 32 bits range => pick kRepWord32.
         return kRepWord32;
-      } else if ((use & kRepMask) == kRepWord32 ||
+      } else if (((use & kRepMask) == kRepWord32 &&
+                  !CanObserveNonWord32(use)) ||
                  (use & kTypeMask) == kTypeInt32 ||
                  (use & kTypeMask) == kTypeUint32) {
         // We only use 32 bits or we use the result consistently.
         return kRepWord32;
       } else {
         return kRepFloat64;
       }
     } else if (upper->Is(Type::Boolean())) {
       // multiple uses => pick kRepBit.
       return kRepBit;
@@ skipping 106 matching lines @@
   bool CanLowerToUint32Binop(Node* node, MachineTypeUnion use) {
     return BothInputsAre(node, Type::Unsigned32()) && !CanObserveNonUint32(use);
   }
 
   bool CanLowerToUint32AdditiveBinop(Node* node, MachineTypeUnion use) {
     return IsSafeIntAdditiveOperand(node->InputAt(0)) &&
            IsSafeIntAdditiveOperand(node->InputAt(1)) &&
            !CanObserveNonUint32(use);
   }
 
+  bool CanObserveNonWord32(MachineTypeUnion use) {
+    return (use & ~(kTypeUint32 | kTypeInt32)) != 0;
+  }
+
   bool CanObserveNonInt32(MachineTypeUnion use) {
     return (use & (kTypeUint32 | kTypeNumber | kTypeAny)) != 0;
   }
 
   bool CanObserveMinusZero(MachineTypeUnion use) {
     // TODO(turbofan): technically Uint32 cannot observe minus zero either.
     return (use & (kTypeUint32 | kTypeNumber | kTypeAny)) != 0;
   }
 
   bool CanObserveNaN(MachineTypeUnion use) {
@@ skipping 1109 matching lines @@
 
 void SimplifiedLowering::DoStringLessThanOrEqual(Node* node) {
   node->set_op(machine()->IntLessThanOrEqual());
   node->ReplaceInput(0, StringComparison(node, true));
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8