c use Makefile test
created a Makefile: build: register_test.c gcc -c register_test.c link: register_test.o gcc -o register_test register_test.o run: register_test ./register_test clean: rm -f *.o *.exe *.executable ou: cd output/ make -C Makefile create a .c file: regitster_test.c (測試用register 有沒有比較省時 #include <stdio.h> #include <sys/time.h> int main( int argc, char* argv[]) { struct timeval start, end; gettimeofday( &start, NULL); double timeuse; register double sum; register int j,k; for(j=0;j<1000000000;j++) for(k=0;k<10;k++) sum=sum+1.0; gettimeofday( &end, NULL); timeuse = 1000000*(end.tv_sec - start.tv_sec)+ end.tv_sec-start.tv_usec; timeuse /= 1000000; printf(" implement time : %f \n", timeuse); return 0; }