xref: /qemu/tests/tcg/cris/libc/check_lz.c (revision 4477035e)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <stdint.h>
4 #include "sys.h"
5 
6 static always_inline int cris_lz(int x)
7 {
8 	int r;
9 	asm ("lz\t%1, %0\n" : "=r" (r) : "r" (x));
10 	return r;
11 }
12 
13 void check_lz(void)
14 {
15 	int i;
16 
17 	if (cris_lz(0) != 32)
18 		err();
19 	if (cris_lz(1) != 31)
20 		err();
21 	if (cris_lz(2) != 30)
22 		err();
23 	if (cris_lz(4) != 29)
24 		err();
25 	if (cris_lz(8) != 28)
26 		err();
27 
28 	/* try all positions with a single bit.  */
29 	for (i = 1; i < 32; i++) {
30 		if (cris_lz(1 << (i-1)) != (32 - i))
31 			err();
32 	}
33 
34 	/* try all positions with all bits.  */
35 	for (i = 1; i < 32; i++) {
36 		/* split up this computation to clarify it.  */
37 		uint32_t val;
38 		val = (unsigned int)-1 >> (32 - i);
39 		if (cris_lz(val) != (32 - i))
40 			err();
41 	}
42 }
43 
44 int main(void)
45 {
46 	check_lz();
47 	pass();
48 	exit(0);
49 }
50