#include <stdio.h> #include<time.h> #include<math.h> #include <unistd.h> clock_t start,stop; //clock_t是clock()函數(shù)返回的變量類型 double duration; //記錄被測試函數(shù)運(yùn)行時(shí)間，以秒為單位#define MAXK 1e7/*被測函數(shù)最大重復(fù)調(diào)用次數(shù)*/void computationtime(double start,double stop,int i) {duration = ((double)(stop-start))/CLOCK_TAI/MAXK;/*計(jì)算函數(shù)單次運(yùn)行的時(shí)間*///計(jì)算運(yùn)行時(shí)間//其它不在測試范圍的處理寫在后面，例如輸出duration的值printf("ticks%d = %f\n",i,(double)(stop - start));printf("duration%d = %6.2e\n",i,duration); }void *fq_memcpy(void *__dest, __const void *__src, size_t __n) {int i = 0;unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;for (i = __n >> 3; i > 0; i--) {*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;}if (__n & 1 << 2) {*d++ = *s++;*d++ = *s++;*d++ = *s++;*d++ = *s++;}if (__n & 1 << 1) {*d++ = *s++;*d++ = *s++;}if (__n & 1)*d++ = *s++;return __dest; }void *fq2_memcpy(void *dest, const void *src, size_t n) {int i;const char *s = src;char *d = dest;for (i = 0; i < n; i++)d[i] = s[i];return dest; }int main(void) {char * a = "0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ,0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ";char b[1024];char c[1024];unsigned int i = 0;start = clock();//開始計(jì)時(shí)for(i=0;i<10*1024;i++)fq_memcpy(c,a,1024);stop = clock();//停止計(jì)時(shí)computationtime(start,stop,1);start = clock();//開始計(jì)時(shí)for(i=0;i<10*1024;i++)fq2_memcpy(b,a,1024);stop = clock();//停止計(jì)時(shí)computationtime(start,stop,1);return 0; }

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