[turbofan] Turn Math.clz32 into an inlinable builtin.

test/unittests/compiler/js-intrinsic-lowering-unittest.cc

 // Copyright 2015 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/access-builder.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-intrinsic-lowering.h"
 #include "src/compiler/js-operator.h"
 #include "test/unittests/compiler/graph-unittest.h"
 #include "test/unittests/compiler/node-test-utils.h"
@@ skipping 206 matching lines @@
                                                 effect, CaptureEq(&if_false)),
                                     effect, _),
                         IsInt32Constant(JS_REGEXP_TYPE)),
           IsMerge(IsIfTrue(AllOf(CaptureEq(&branch),
                                  IsBranch(IsObjectIsSmi(input), control))),
                   AllOf(CaptureEq(&if_false), IsIfFalse(CaptureEq(&branch))))));
 }
 
 
 // -----------------------------------------------------------------------------
+// %_MathClz32
+
+
+TEST_F(JSIntrinsicLoweringTest, InlineMathClz32) {
+  Node* const input = Parameter(0);
+  Node* const context = Parameter(1);
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Reduction const r = Reduce(
+      graph()->NewNode(javascript()->CallRuntime(Runtime::kInlineMathClz32, 1),
+                       input, context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(), IsWord32Clz(input));
+}
+
+
+// -----------------------------------------------------------------------------
 // %_ValueOf
 
 
 TEST_F(JSIntrinsicLoweringTest, InlineValueOf) {
   Node* const input = Parameter(0);
   Node* const context = Parameter(1);
   Node* const effect = graph()->start();
   Node* const control = graph()->start();
   Reduction const r = Reduce(
       graph()->NewNode(javascript()->CallRuntime(Runtime::kInlineValueOf, 1),
@@ skipping 24 matching lines @@
                             CaptureEq(&if_false0)))))),
           IsMerge(
               IsIfTrue(AllOf(CaptureEq(&branch0),
                              IsBranch(IsObjectIsSmi(input), control))),
               AllOf(CaptureEq(&if_false0), IsIfFalse(CaptureEq(&branch0))))));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8