xref: /openbmc/qemu/tests/tcg/s390x/float.h (revision 6e7c96ae)
1 /*
2  * Helpers for floating-point tests.
3  *
4  * SPDX-License-Identifier: GPL-2.0-or-later
5  */
6 #ifndef FLOAT_H
7 #define FLOAT_H
8 
9 /*
10  * Floating-point value classes.
11  */
12 #define N_FORMATS 3
13 #define CLASS_MINUS_INF 0
14 #define CLASS_MINUS_FN 1
15 #define CLASS_MINUS_ZERO 2
16 #define CLASS_PLUS_ZERO 3
17 #define CLASS_PLUS_FN 4
18 #define CLASS_PLUS_INF 5
19 #define CLASS_QNAN 6
20 #define CLASS_SNAN 7
21 #define N_SIGNED_CLASSES 8
22 static const size_t float_sizes[N_FORMATS] = {
23     /* M4 == 2: short    */ 4,
24     /* M4 == 3: long     */ 8,
25     /* M4 == 4: extended */ 16,
26 };
27 static const size_t e_bits[N_FORMATS] = {
28     /* M4 == 2: short    */ 8,
29     /* M4 == 3: long     */ 11,
30     /* M4 == 4: extended */ 15,
31 };
32 struct float_class {
33     size_t n;
34     unsigned char v[2][16];
35 };
36 static const struct float_class signed_floats[N_FORMATS][N_SIGNED_CLASSES] = {
37     /* M4 == 2: short */
38     {
39         /* -inf */ {1, {{0xff, 0x80, 0x00, 0x00}}},
40         /* -Fn */  {2, {{0xc2, 0x28, 0x00, 0x00},
41                         {0xc2, 0x29, 0x00, 0x00}}},
42         /* -0 */   {1, {{0x80, 0x00, 0x00, 0x00}}},
43         /* +0 */   {1, {{0x00, 0x00, 0x00, 0x00}}},
44         /* +Fn */  {2, {{0x42, 0x28, 0x00, 0x00},
45                         {0x42, 0x2a, 0x00, 0x00}}},
46         /* +inf */ {1, {{0x7f, 0x80, 0x00, 0x00}}},
47         /* QNaN */ {2, {{0x7f, 0xff, 0xff, 0xff},
48                         {0x7f, 0xff, 0xff, 0xfe}}},
49         /* SNaN */ {2, {{0x7f, 0xbf, 0xff, 0xff},
50                         {0x7f, 0xbf, 0xff, 0xfd}}},
51     },
52 
53     /* M4 == 3: long */
54     {
55         /* -inf */ {1, {{0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
56         /* -Fn */  {2, {{0xc0, 0x45, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
57                         {0xc0, 0x46, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
58         /* -0 */   {1, {{0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
59         /* +0 */   {1, {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
60         /* +Fn */  {2, {{0x40, 0x45, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
61                         {0x40, 0x47, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
62         /* +inf */ {1, {{0x7f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
63         /* QNaN */ {2, {{0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
64                         {0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe}}},
65         /* SNaN */ {2, {{0x7f, 0xf7, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
66                         {0x7f, 0xf7, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd}}},
67     },
68 
69     /* M4 == 4: extended */
70     {
71         /* -inf */ {1, {{0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
72         /* -Fn */  {2, {{0xc0, 0x04, 0x50, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
73                         {0xc0, 0x04, 0x51, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
74         /* -0 */   {1, {{0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
75         /* +0 */   {1, {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
76         /* +Fn */  {2, {{0x40, 0x04, 0x50, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
77                         {0x40, 0x04, 0x52, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
78         /* +inf */ {1, {{0x7f, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}},
79         /* QNaN */ {2, {{0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
80                         {0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe}}},
81         /* SNaN */ {2, {{0x7f, 0xff, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
82                         {0x7f, 0xff, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd}}},
83     },
84 };
85 static const unsigned char default_nans[N_FORMATS][16] = {
86     /* M4 == 2: short    */ {0x7f, 0xc0, 0x00, 0x00},
87     /* M4 == 3: long     */ {0x7f, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
88     /* M4 == 4: extended */ {0x7f, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
89 };
90 
91 static void dump_v(FILE *f, const void *v, size_t n)
92 {
93     for (int i = 0; i < n; i++) {
94         fprintf(f, "%02x", ((const unsigned char *)v)[i]);
95     }
96 }
97 
98 static void snan_to_qnan(char *v, int fmt)
99 {
100     size_t bit = 1 + e_bits[fmt];
101     v[bit / 8] |= 1 << (7 - (bit % 8));
102 }
103 
104 #endif
105