Fix unused-variable error on release builds.

src/arm/assembler-arm.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 3158 matching lines @@
   int immed8 = Instruction::Immed8Value(instr);
   return (immed8 >> rotate) | (immed8 << (32 - rotate));
 }
 
 
 Instr Assembler::PatchShiftImm(Instr instr, int immed) {
   uint32_t rotate_imm = 0;
   uint32_t immed_8 = 0;
   bool immed_fits = fits_shifter(immed, &rotate_imm, &immed_8, NULL);
   DCHECK(immed_fits);
+  USE(immed_fits);
   return (instr & ~kOff12Mask) | (rotate_imm << 8) | immed_8;
 }
 
 
 bool Assembler::IsNop(Instr instr, int type) {
   DCHECK(0 <= type && type <= 14);  // mov pc, pc isn't a nop.
   // Check for mov rx, rx where x = type.
   return instr == (al | 13*B21 | type*B12 | type);
 }
 
@@ skipping 644 matching lines @@
       assm->instr_at_put(
           rinfo.pc(), Assembler::SetLdrRegisterImmediateOffset(instr, offset));
     }
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM