ARM_ORIG_r0
#define MAX_REG_OFFSET (offsetof(struct pt_regs, ARM_ORIG_r0))
regs->ARM_ORIG_r0 = regs->ARM_r0;
regs->ARM_r0 = regs->ARM_ORIG_r0;
args[0] = regs->ARM_ORIG_r0;
DEFINE(S_OLD_R0, offsetof(struct pt_regs, ARM_ORIG_r0));
regs->ARM_r0 = regs->ARM_ORIG_r0;
regs->ARM_ORIG_r0 = ~0UL;