qemu/tests/cris/check_lz.c

50 lines
768 B
C

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include "sys.h"
static inline int cris_lz(int x)
{
int r;
asm ("lz\t%1, %0\n" : "=r" (r) : "r" (x));
return r;
}
void check_lz(void)
{
int i;
if (cris_lz(0) != 32)
err();
if (cris_lz(1) != 31)
err();
if (cris_lz(2) != 30)
err();
if (cris_lz(4) != 29)
err();
if (cris_lz(8) != 28)
err();
/* try all positions with a single bit. */
for (i = 1; i < 32; i++) {
if (cris_lz(1 << (i-1)) != (32 - i))
err();
}
/* try all positions with all bits. */
for (i = 1; i < 32; i++) {
/* split up this computation to clarify it. */
uint32_t val;
val = (unsigned int)-1 >> (32 - i);
if (cris_lz(val) != (32 - i))
err();
}
}
int main(void)
{
check_lz();
pass();
exit(0);
}