Implement Smi_bitLength intrinsic on mips, arm, and arm64.

runtime/vm/constants_arm64.h

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_CONSTANTS_ARM64_H_
 #define VM_CONSTANTS_ARM64_H_
 
 #include "platform/assert.h"
 
 namespace dart {
@@ skipping 420 matching lines @@
 
 // C3.5.6
 enum ConditionalSelectOp {
   ConditionalSelectMask = 0x1fe00000,
   ConditionalSelectFixed = DPRegisterFixed | B28 | B23,
   CSEL = ConditionalSelectFixed,
   CSINC = ConditionalSelectFixed | B10,
   CSINV = ConditionalSelectFixed | B30,
 };
 
+// C3.5.7
+enum MiscDP1SourceOp {
+  MiscDP1SourceMask = 0x5fe00000,
+  MiscDP1SourceFixed = DPRegisterFixed | B30 | B28 | B23 | B22,
+  CLZ = MiscDP1SourceFixed | B12,
+};
+
 // C3.5.8
 enum MiscDP2SourceOp {
   MiscDP2SourceMask = 0x5fe00000,
   MiscDP2SourceFixed = DPRegisterFixed | B28 | B23 | B22,
   UDIV = MiscDP2SourceFixed | B11,
   SDIV = MiscDP2SourceFixed | B11 | B10,
   LSLV = MiscDP2SourceFixed | B13,
   LSRV = MiscDP2SourceFixed | B13 | B10,
   ASRV = MiscDP2SourceFixed | B13 | B11,
 };
@@ skipping 151 matching lines @@
 _V(LoadStoreReg)                                                               \
 _V(LoadStoreRegPair)                                                           \
 _V(LoadRegLiteral)                                                             \
 _V(AddSubImm)                                                                  \
 _V(LogicalImm)                                                                 \
 _V(MoveWide)                                                                   \
 _V(PCRel)                                                                      \
 _V(AddSubShiftExt)                                                             \
 _V(AddSubWithCarry)                                                            \
 _V(ConditionalSelect)                                                          \
+_V(MiscDP1Source)                                                              \
 _V(MiscDP2Source)                                                              \
 _V(MiscDP3Source)                                                              \
 _V(LogicalShift)                                                               \
 _V(SIMDCopy)                                                                   \
 _V(SIMDThreeSame)                                                              \
 _V(SIMDTwoReg)                                                                 \
 _V(FPCompare)                                                                  \
 _V(FPOneSource)                                                                \
 _V(FPTwoSource)                                                                \
 _V(FPImm)                                                                      \
@@ skipping 437 matching lines @@
   static Instr* At(uword pc) { return reinterpret_cast<Instr*>(pc); }
 
  private:
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Instr);
 };
 
 }  // namespace dart
 
 #endif  // VM_CONSTANTS_ARM64_H_