2.62 判断机器是否进行算数右移

Posted 2020-12-15 lonelytraveler

//csapp 2.62

#include <stdio.h>                                                                                                                                                                 
//算数右移返回1，否则返回0
int int_shifts_are_arithmetic() 
{
    //return !~(-1>>1);
    unsigned int w = sizeof(int)<<3;
    return !~(1<<(w-1)>>(w-1));
}

int main(void)
{
    printf("expect:1, result:%d
", int_shifts_are_arithmetic());
}