[turbofan] Propagate minus-zero truncation in representation inference.

test/cctest/compiler/test-representation-change.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 <limits>
 
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/representation-change.h"
 #include "src/objects-inl.h"
 #include "test/cctest/cctest.h"
@@ skipping 427 matching lines @@
   CheckTwoChanges(IrOpcode::kChangeFloat32ToFloat64,
                   IrOpcode::kTruncateFloat64ToWord32,
                   MachineRepresentation::kFloat32, Type::Number(),
                   MachineRepresentation::kWord32);
 }
 
 static void TestMinusZeroCheck(IrOpcode::Value expected, Type* from_type) {
   RepresentationChangerTester r;
 
   CheckChange(expected, MachineRepresentation::kFloat64, from_type,
-              UseInfo::CheckedSignedSmallAsWord32(
-                  CheckForMinusZeroMode::kCheckForMinusZero));
+              UseInfo::CheckedSignedSmallAsWord32(kDistinguishZeros));
 
   CheckChange(expected, MachineRepresentation::kFloat64, from_type,
-              UseInfo::CheckedSignedSmallAsWord32(
-                  CheckForMinusZeroMode::kDontCheckForMinusZero));
+              UseInfo::CheckedSignedSmallAsWord32(kIdentifyZeros));
 
   CheckChange(expected, MachineRepresentation::kFloat64, from_type,
-              UseInfo::CheckedSigned32AsWord32(
-                  CheckForMinusZeroMode::kCheckForMinusZero));
+              UseInfo::CheckedSigned32AsWord32(kDistinguishZeros));
 
   CheckChange(expected, MachineRepresentation::kFloat64, from_type,
-              UseInfo::CheckedSigned32AsWord32(
-                  CheckForMinusZeroMode::kDontCheckForMinusZero));
+              UseInfo::CheckedSigned32AsWord32(kDistinguishZeros));
 }
 
 TEST(MinusZeroCheck) {
   TestMinusZeroCheck(IrOpcode::kCheckedFloat64ToInt32, Type::NumberOrOddball());
   // PlainNumber cannot be minus zero so the minus zero check should be
   // eliminated.
   TestMinusZeroCheck(IrOpcode::kCheckedFloat64ToInt32, Type::PlainNumber());
 }
 
 TEST(Nops) {
@@ skipping 59 matching lines @@
                    MachineRepresentation::kWord64);
   r.CheckTypeError(MachineRepresentation::kWord32, Type::Signed32(),
                    MachineRepresentation::kWord64);
   r.CheckTypeError(MachineRepresentation::kWord32, Type::Unsigned32(),
                    MachineRepresentation::kWord64);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8