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/*
!!DESCRIPTION!! Implementation of Duff's device (loop unrolling).
!!ORIGIN!!
!!LICENCE!! GPL, read COPYING.GPL
*/
#include <stdio.h>
#include <limits.h>
#define ASIZE (100)
unsigned char success=0;
unsigned char failures=0;
unsigned char dummy=0;
#ifdef SUPPORT_BIT_TYPES
bit bit0 = 0;
#endif
void done()
{
dummy++;
}
int acmp(char* a, char* b, int count)
{
int i;
for(i = 0; i < count; i++) {
if(a[i] != b[i]) {
return 1;
}
}
return 0;
}
void duffit (char* to, char* from, int count)
{
int n = (count + 7) / 8;
switch(count % 8) {
case 0: do { *to++ = *from++;
case 7: *to++ = *from++;
case 6: *to++ = *from++;
case 5: *to++ = *from++;
case 4: *to++ = *from++;
case 3: *to++ = *from++;
case 2: *to++ = *from++;
case 1: *to++ = *from++;
} while(--n > 0);
}
}
int main(void)
{
char a[ASIZE] = {1};
char b[ASIZE] = {2};
/* a and b should be different */
if(!acmp(a, b, ASIZE)) {
failures++;
}
duffit(a, b, ASIZE);
/* a and b should be the same */
if(acmp(a, b, ASIZE)) {
failures++;
}
success=failures;
done();
printf("failures: %d\n",failures);
return failures;
}
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