binary-operator-reducer: reduce mul+div(shift)

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 7ffdfe5bf08a0e9806b74b014ffb0ded2c62f72e..6f7ed3aca48df98ad15a36510582cb44563a85b6 100644
--- a/test/unittests/compiler/machine-operator-reducer-unittest.cc
+++ b/test/unittests/compiler/machine-operator-reducer-unittest.cc
@@ -1646,6 +1646,18 @@ TEST_F(MachineOperatorReducerTest, StoreRepWord16WithWord32SarAndWord32Shl) {
   }
 }
 
+
+TEST_F(MachineOperatorReducerTest, RoundPlusTruncate) {
+  Node* p0 = Parameter(0);
+  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);
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8