tests/cris/check_lz.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <stdint.h>
   4 #include "sys.h"
   5
   6 static 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 }