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1 #include <assert.h>
2 #include <stdlib.h>
3 #include <stdio.h>
4 #include "opcodes.h"
5 
6 #define srnm(b,d) \
7    ({ \
8       __asm__ volatile ( "lghi 8," #b "\n\t" \
9                          "srnm " #d "(8)\n\t" ::: "8"); \
10    })
11 
12 unsigned
get_rounding_mode(void)13 get_rounding_mode(void)
14 {
15    unsigned fpc;
16 
17    __asm__ volatile ("stfpc  %0\n\t" : "=m"(fpc));
18 
19    return fpc & 0x7;
20 }
21 
main(void)22 int main(void)
23 {
24    printf("initial rounding mode = %u\n", get_rounding_mode());
25 
26    /* Set basic rounding modes in various ways */
27    srnm(1,2);  // 1 + 2 = 3
28    printf("rounding mode = %u\n", get_rounding_mode());
29 
30    srnm(2,0);
31    printf("rounding mode = %u\n", get_rounding_mode());
32 
33    srnm(0,1);
34    printf("rounding mode = %u\n", get_rounding_mode());
35 
36    srnm(0,0);
37    printf("rounding mode = %u\n", get_rounding_mode());
38 
39    /* Some rounding modes with bits to be ignored */
40    srnm(0xff,0);  // -> 3
41    printf("rounding mode = %u\n", get_rounding_mode());
42 
43    srnm(0,0xfe);  // -> 2
44    printf("rounding mode = %u\n", get_rounding_mode());
45 
46    srnm(0xf0,0x0f);  // -> 3
47    printf("rounding mode = %u\n", get_rounding_mode());
48 
49    return 0;
50 }
51