[turbofan] Don't insert {Int32Constant}s in JSCallReducer

Bug: chromium:814336, v8:7250, v8:7340
Change-Id: I9345778cabf24f1278ca7364ef7e223038c5aeee
Reviewed-on: https://chromium-review.googlesource.com/929121
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51468}

src/compiler/js-call-reducer.cc

@@ -115,7 +115,7 @@ Reduction JSCallReducer::ReduceMathClz32(Node* node) {
     return NoChange();
   }
   if (node->op()->ValueInputCount() < 3) {
-    Node* value = jsgraph()->Int32Constant(32);
+    Node* value = jsgraph()->Constant(32);
     ReplaceWithValue(node, value);
     return Replace(value);
   }

test/unittests/compiler/js-call-reducer-unittest.cc

@@ -251,8 +251,24 @@ TEST_F(JSCallReducerTest, MathClz32WithUnsigned32) {
   Reduction r = Reduce(call);
 
   ASSERT_TRUE(r.Changed());
-  EXPECT_THAT(std::string(IrOpcode::Mnemonic(r.replacement()->opcode())),
-              op_name_for("clz32"));
+  EXPECT_THAT(r.replacement(),
+              IsNumberClz32(IsNumberToUint32(IsSpeculativeToNumber(p0))));
+}
+
+TEST_F(JSCallReducerTest, MathClz32WithUnsigned32NoArg) {
+  Node* jsfunction = MathFunction("clz32");
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+
+  Node* call =
+      graph()->NewNode(javascript()->Call(2), jsfunction, UndefinedConstant(),
+                       context, frame_state, effect, control);
+  Reduction r = Reduce(call);
+
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(), IsNumberConstant(32));
 }
 
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