ARM: Make use of d16-d31 when available.

src/flag-definitions.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 285 matching lines @@
             "enable use of VFP2 instructions if available")
 DEFINE_bool(enable_armv7, true,
             "enable use of ARMv7 instructions if available (ARM only)")
 DEFINE_bool(enable_sudiv, true,
             "enable use of SDIV and UDIV instructions if available (ARM only)")
 DEFINE_bool(enable_movw_movt, false,
             "enable loading 32-bit constant by means of movw/movt "
             "instruction pairs (ARM only)")
 DEFINE_bool(enable_unaligned_accesses, true,
             "enable unaligned accesses for ARMv7 (ARM only)")
+DEFINE_bool(enable_32dregs, true,
+            "enable use of d16-d31 registers on ARM - this requires VFP3")
 DEFINE_bool(enable_fpu, true,
             "enable use of MIPS FPU instructions if available (MIPS only)")
 DEFINE_bool(enable_vldr_imm, false,
             "enable use of constant pools for double immediate (ARM only)")
 
 // bootstrapper.cc
 DEFINE_string(expose_natives_as, NULL, "expose natives in global object")
 DEFINE_string(expose_debug_as, NULL, "expose debug in global object")
 DEFINE_bool(expose_gc, false, "expose gc extension")
 DEFINE_bool(expose_externalize_string, false,
@@ skipping 402 matching lines @@
 #undef DEFINE_bool
 #undef DEFINE_int
 #undef DEFINE_string
 #undef DEFINE_implication
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META
 #undef FLAG_MODE_DEFINE_IMPLICATIONS