[machine-operator-reducer] fix float truncation

test/unittests/compiler/machine-operator-reducer-unittest.cc

Index: test/unittests/compiler/machine-operator-reducer-unittest.cc
diff --git a/test/unittests/compiler/machine-operator-reducer-unittest.cc b/test/unittests/compiler/machine-operator-reducer-unittest.cc
index 6f7ed3aca48df98ad15a36510582cb44563a85b6..9e1ed6efdc0aee8e0eef8d3378d214cd424b3124 100644
--- a/test/unittests/compiler/machine-operator-reducer-unittest.cc
+++ b/test/unittests/compiler/machine-operator-reducer-unittest.cc
@@ -1649,13 +1649,34 @@ TEST_F(MachineOperatorReducerTest, StoreRepWord16WithWord32SarAndWord32Shl) {
 
 TEST_F(MachineOperatorReducerTest, RoundPlusTruncate) {
   Node* p0 = Parameter(0);
+
+  Type* p0_range = Type::Range(0x0, 0xFFFFFF8000001ULL, graph()->zone());
+  NodeProperties::SetType(
+      p0, Type::Intersect(p0_range, Type::Number(), graph()->zone()));
+
   Node* t0 = graph()->NewNode(machine()->RoundInt64ToFloat64(), p0);
   Node* t1 = graph()->NewNode(
       machine()->TruncateFloat64ToInt32(TruncationMode::kJavaScript), t0);
 
   Reduction r = Reduce(t1);
   ASSERT_TRUE(r.Changed());
-  EXPECT_THAT(r.replacement(), p0);
+  EXPECT_THAT(r.replacement(), IsTruncateInt64ToInt32(p0));
+}
+
+
+TEST_F(MachineOperatorReducerTest, OverflowingRoundPlusTruncate) {
+  Node* p0 = Parameter(0);
+
+  Type* p0_range = Type::Range(0x0, 0x10000000000000ULL, graph()->zone());
+  NodeProperties::SetType(
+      p0, Type::Intersect(p0_range, Type::Number(), graph()->zone()));
+
+  Node* t0 = graph()->NewNode(machine()->RoundInt64ToFloat64(), p0);
+  Node* t1 = graph()->NewNode(
+      machine()->TruncateFloat64ToInt32(TruncationMode::kJavaScript), t0);
+
+  Reduction r = Reduce(t1);
+  ASSERT_TRUE(!r.Changed());
 }
 
 }  // namespace compiler