ARM: Make use of d16-d31 when available.

src/arm/macro-assembler-arm.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 979 matching lines @@
 
   // Count leading zeros in a 32 bit word.  On ARM5 and later it uses the clz
   // instruction.  On pre-ARM5 hardware this routine gives the wrong answer
   // for 0 (31 instead of 32).  Source and scratch can be the same in which case
   // the source is clobbered.  Source and zeros can also be the same in which
   // case scratch should be a different register.
   void CountLeadingZeros(Register zeros,
                          Register source,
                          Register scratch);
 
+  // Check whether d16-d31 are available on the CPU. The result is given by the
+  // Z condition flag: Z==0 if d16-d31 available, Z==1 otherwise.
+  void CheckFor32DRegs(Register scratch);
+
+
   // ---------------------------------------------------------------------------
   // Runtime calls
 
   // Call a code stub.
   void CallStub(CodeStub* stub,
                 TypeFeedbackId ast_id = TypeFeedbackId::None(),
                 Condition cond = al);
 
   // Call a code stub.
   void TailCallStub(CodeStub* stub, Condition cond = al);
@@ skipping 417 matching lines @@
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_MACRO_ASSEMBLER_ARM_H_