为什么较大的比较会变成1行汇编代码? [英] Why did a large comparison become 1 line of assembler code?

问题描述

在在此处评论中的建议之后，我试图了解

Following a suggestion in a comment here, I'm trying to understand how does Compiler Explorer work. My input is the following piece of code:

int main() {
    double x,y,x0,y0,x1,y1;
    x = 10;
    y = 10;
    x0 = 5;
    y0 = 5;
    x1 = 15;
    y1 = 15;
    if (x > x0 && x < x1 && y > y0 && y < y1)
        return 1;
    return 0;
}

结果是:

    mov     eax, 1
    ret

很多年前，我已经学习了汇编程序的基础知识，但是我不知道这是否有意义.可以? (我试图找到的是，如果在两次收益之间添加"else"会不会对性能产生任何影响.根据此网站，这没有.但是我说对了吗?)

I have learned the basics of assembler many years ago, but I don't know if, or how, this makes any sense. Does it? (What I was trying to find is if adding an "else" between the two returns would have any difference in performance. According to this site, it doesn't. But am I getting it right?)

推荐答案

条件为true.编译器对其进行了优化.它会为return 1;生成代码.

The condition is true. The compiler optimizes it out; it generates code for return 1;.

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