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9#include <stdio.h>
10#include <stdlib.h>
11#include <math.h>
12#include <float.h>
13#include <fenv.h>
14
15#include "float_helpers.h"
16
17#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
18
19typedef struct {
20 int flag;
21 char *desc;
22} float_mapping;
23
24float_mapping round_flags[] = {
25 { FE_TONEAREST, "to nearest" },
26#ifdef FE_UPWARD
27 { FE_UPWARD, "upwards" },
28#endif
29#ifdef FE_DOWNWARD
30 { FE_DOWNWARD, "downwards" },
31#endif
32 { FE_TOWARDZERO, "to zero" }
33};
34
35
36static void print_inputs(float a, float b, float c)
37{
38 char *a_fmt, *b_fmt, *c_fmt;
39
40 a_fmt = fmt_f32(a);
41 b_fmt = fmt_f32(b);
42 c_fmt = fmt_f32(c);
43
44 printf("op : %s * %s + %s\n", a_fmt, b_fmt, c_fmt);
45
46 free(a_fmt);
47 free(b_fmt);
48 free(c_fmt);
49}
50
51static void print_result(float r, int j, int k)
52{
53 char *r_fmt, *flag_fmt;
54
55 r_fmt = fmt_f32(r);
56 flag_fmt = fmt_flags();
57
58 printf("res: %s flags=%s (%d/%d)\n", r_fmt, flag_fmt, j, k);
59
60 free(r_fmt);
61 free(flag_fmt);
62}
63
64static void do_madds(float a, float b, float c, int j, int k)
65{
66 float r;
67
68 print_inputs(a, b, c);
69
70 feclearexcept(FE_ALL_EXCEPT);
71 r = __builtin_fmaf(a, b, c);
72
73 print_result(r, j, k);
74}
75
76int main(int argc, char *argv[argc])
77{
78 int i, j, k, nums = get_num_f32();
79 float a, b, c;
80
81 for (i = 0; i < ARRAY_SIZE(round_flags); ++i) {
82 if (fesetround(round_flags[i].flag) != 0) {
83 printf("### Rounding %s skipped\n", round_flags[i].desc);
84 continue;
85 }
86 printf("### Rounding %s\n", round_flags[i].desc);
87 for (j = 0; j < nums; j++) {
88 for (k = 0; k < 3; k++) {
89 a = get_f32(j + ((k)%3));
90 b = get_f32(j + ((k+1)%3));
91 c = get_f32(j + ((k+2)%3));
92 do_madds(a, b, c, j, k);
93 }
94 }
95
96
97 printf("# LP184149\n");
98 do_madds(0x1.ffffffffffffcp-1022, 0x1.0000000000001p-1, 0x0.0000000000001p-1022, j, 0);
99 do_madds(0x8p-152, 0x8p-152, 0x8p-152, j+1, 0);
100 }
101
102 return 0;
103}
104
