Land bug 996883. r=mjrosenb

js/src/jit/arm/MacroAssembler-arm.cpp

@@ -365,7 +365,7 @@ MacroAssemblerARM::ma_alu(Register src1, Imm32 imm, Register dest,
 
     // And try with its negative.
     if (negOp != op_invalid &&
-        alu_dbl(src1, negImm, dest, negOp, sc, c))
+        alu_dbl(src1, negImm, negDest, negOp, sc, c))
         return;
 
     // Well, damn. We can use two 16 bit mov's, then do the op