[arm][arm64] Improve CountTrailingZero implementation.

src/compiler/arm64/instruction-scheduler-arm64.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 "src/compiler/instruction-scheduler.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
@@ skipping 57 matching lines @@
     case kArm64Ror32:
     case kArm64Mov32:
     case kArm64Sxtb32:
     case kArm64Sxth32:
     case kArm64Sxtw:
     case kArm64Sbfx32:
     case kArm64Ubfx:
     case kArm64Ubfx32:
     case kArm64Ubfiz32:
     case kArm64Bfi:
+    case kArm64Rbit:
+    case kArm64Rbit32:
     case kArm64Float32Cmp:
     case kArm64Float32Add:
     case kArm64Float32Sub:
     case kArm64Float32Mul:
     case kArm64Float32Div:
     case kArm64Float32Max:
     case kArm64Float32Min:
     case kArm64Float32Abs:
     case kArm64Float32Sqrt:
     case kArm64Float32RoundDown:
@@ skipping 133 matching lines @@
       return 5;
 
     default:
       return 1;
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8