c++ - 关于strcmp()的一种实现算法的疑问-Fragen und Antworten zum chinesischen PHP-Netzwerk

在《See MIPS Run》的Chapter 9 Reading MIPS Assembly Language中，提到到这样一段代码：

We’ll use the same example as in Chapter 8: an implementation of the C library function strcmp(). But this time we’ll include essential elements of assembly syntax and also show some hand-optimized and -scheduled code. The algorithm shown is somewhat cleverer than a naïve strcmp() function; we’ll start with this code—still in C—in a form that has all the operations separated out to make them easier to play with, as follows:
int strcmp (char *a0, char *a1) { char t0, t1; while (1) { t0 = a0[0]; a0 += 1; t1 = a1[0]; a1 += 1; if (t0 == 0) break; if (t0 != t1) break; } return (t0 - t1); }

图片版的原文在此：

不是很懂t0 = a0[0];t1 = a1[0];这个为什么放在while循环里。。。这样难道不是每次循环都从首字符开始了么。。。那么怎么完成字符串的比较呢？

还要一个疑问是。。。if (t0 == 0)难道不应该是if (t0 =='\0')么。。。

int myStrcmp(const char* dest, const char* src) { // 循环条件每个字符都相等 // 并且两个字符串都没有到结尾 // 一旦以上某个条件不满足则跳出while while (*dest == *src && *dest != '\0' && *src != '\0') { dest++; src++; } // 此时计算最后指向的两个字符的差值，返回对应值即可 return *dest > *src ? 1 : (*dest == *src ? 0 : -1); }