sc_a0 27 arch/c6x/include/uapi/asm/sigcontext.h unsigned long sc_a0; sc_a0 10 arch/m68k/include/uapi/asm/sigcontext.h unsigned long sc_a0; sc_a0 712 arch/m68k/kernel/signal.c regs->a0 = context.sc_a0; sc_a0 839 arch/m68k/kernel/signal.c sc->sc_a0 = regs->a0;