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/* Duff's device is legal C; test to make sure the compiler
doesn't complain about it.
Jason Thorpe <thorpej@wasabisystems.com>
Derived from Tom Duff's original usenet message about the device. */
/* { dg-do run } */
/* { dg-options "-O2" } */
extern void abort (void);
extern void exit (int);
typedef __SIZE_TYPE__ size_t;
extern int memcmp (const void *, const void *, size_t);
void
duffcpy (char *dst, const char *src, unsigned long size)
{
unsigned long n = (size + 7) / 8;
switch (size % 8)
{
case 0: do { *dst++ = *src++;
case 7: *dst++ = *src++;
case 6: *dst++ = *src++;
case 5: *dst++ = *src++;
case 4: *dst++ = *src++;
case 3: *dst++ = *src++;
case 2: *dst++ = *src++;
case 1: *dst++ = *src++;
} while (--n > 0);
}
}
const char testpat[] = "The quick brown fox jumped over the lazy dog.";
int
main()
{
char buf[64];
duffcpy (buf, testpat, sizeof (testpat));
if (memcmp (buf, testpat, sizeof (testpat)) != 0)
abort ();
exit (0);
}
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