ARM: Make use of d16-d31 when available.

src/mips/assembler-mips.h

Index: src/mips/assembler-mips.h
diff --git a/src/mips/assembler-mips.h b/src/mips/assembler-mips.h
index 75d110a36cb2f3530e937fc90102a3dc4ca1dcfd..605746f585b396c28f521ed4a6bef4a19d31e2cb 100644
--- a/src/mips/assembler-mips.h
+++ b/src/mips/assembler-mips.h
@@ -200,6 +200,8 @@ struct FPURegister {
   static const int kNumAllocatableRegisters = kNumRegisters / 2 -
       kNumReservedRegisters;
 
+  static int NumAllocatableRegisters() { return kNumAllocatableRegisters; }
+
 
   inline static int ToAllocationIndex(FPURegister reg);