__set_cpsr_c
static __inline uint32_t __set_cpsr_c(uint32_t bic, uint32_t eor) __attribute__((__unused__));
(__set_cpsr_c((I32_bit | F32_bit), (old_cpsr) & (I32_bit | F32_bit)))
#define IRQdisable __set_cpsr_c(I32_bit, I32_bit);
#define IRQenable __set_cpsr_c(I32_bit, 0);
#define MCOUNT_ENTER s = __set_cpsr_c(0x0080, 0x0080); /* kill IRQ */
#define MCOUNT_EXIT __set_cpsr_c(0xffffffff, s); /* restore old value */