1 /*
2 * Copyright © 2021 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 #include <math.h>
25 #include <gtest/gtest.h>
26
27 #include "util/half_float.h"
28 #include "util/u_math.h"
29
30 /* math.h has some defines for these, but they have some compiler dependencies
31 * and can potentially raise exceptions.
32 */
33 #define TEST_POS_INF (uif(0x7f800000))
34 #define TEST_NEG_INF (uif(0xff800000))
35 #define TEST_NAN (uif(0x7fc00000))
36
37 #define HALF_POS_INF 0x7c00
38 #define HALF_NEG_INF 0xfc00
39 #define HALF_NAN 0x7e00
40
41 #ifndef HAVE_ISSIGNALING
issignaling(float x)42 static bool issignaling(float x)
43 {
44 uint32_t ui = fui(x);
45 return (((ui >> 23) & 0xff) == 0xff) && !(ui & (1 << 22));
46 }
47 #endif
48
49 /* Sanity test our test values */
TEST(half_to_float_test,nan_test)50 TEST(half_to_float_test, nan_test)
51 {
52 EXPECT_TRUE(isinf(TEST_POS_INF));
53 EXPECT_TRUE(isinf(TEST_NEG_INF));
54
55 EXPECT_TRUE(isnan(TEST_NAN));
56 /* Make sure that our 32-bit float nan test value we're using is a
57 * non-signaling NaN. The sign of the bit for signaling was apparently
58 * different on some old processors (PA-RISC, MIPS?). This test value should
59 * cover Intel, ARM, and PPC, for sure.
60 */
61 EXPECT_FALSE(issignaling(TEST_NAN));
62 }
63
64 static void
test_half_to_float_limits(float (* func)(uint16_t))65 test_half_to_float_limits(float (*func)(uint16_t))
66 {
67 /* Positive and negative 0. */
68 EXPECT_EQ(func(0), 0.0f);
69 EXPECT_EQ(fui(func(0x8000)), fui(-0.0f));
70
71 /* Max normal number */
72 EXPECT_EQ(func(0x7bff), 65504.0f);
73
74 float nan = func(HALF_NAN);
75 EXPECT_TRUE(isnan(nan));
76 EXPECT_FALSE(issignaling(nan));
77
78 /* inf */
79 EXPECT_EQ(func(HALF_POS_INF), TEST_POS_INF);
80 /* -inf */
81 EXPECT_EQ(func(HALF_NEG_INF), TEST_NEG_INF);
82 }
83
84 /* Test the optionally HW instruction-using path. */
TEST(half_to_float_test,half_to_float_test)85 TEST(half_to_float_test, half_to_float_test)
86 {
87 test_half_to_float_limits(_mesa_half_to_float);
88 }
89
TEST(half_to_float_test,half_to_float_slow_test)90 TEST(half_to_float_test, half_to_float_slow_test)
91 {
92 test_half_to_float_limits(_mesa_half_to_float_slow);
93 }
94
95 static void
test_float_to_half_limits(uint16_t (* func)(float))96 test_float_to_half_limits(uint16_t (*func)(float))
97 {
98 /* Positive and negative 0. */
99 EXPECT_EQ(func(0.0f), 0);
100 EXPECT_EQ(func(-0.0f), 0x8000);
101
102 /* Max normal number */
103 EXPECT_EQ(func(65504.0f), 0x7bff);
104
105 uint16_t nan = func(TEST_NAN);
106 EXPECT_EQ((nan & 0xfc00), 0x7c00); /* exponent is all 1s */
107 EXPECT_TRUE(nan & (1 << 9)); /* mantissa is quiet nan */
108
109 EXPECT_EQ(func(TEST_POS_INF), HALF_POS_INF);
110 EXPECT_EQ(func(TEST_NEG_INF), HALF_NEG_INF);
111 }
112
TEST(float_to_half_test,float_to_half_test)113 TEST(float_to_half_test, float_to_half_test)
114 {
115 test_float_to_half_limits(_mesa_float_to_half);
116 }
117
TEST(float_to_float16_rtne_test,float_to_float16_rtne_test)118 TEST(float_to_float16_rtne_test, float_to_float16_rtne_test)
119 {
120 test_float_to_half_limits(_mesa_float_to_float16_rtne);
121 }
122
123 /* no rtne_slow variant -- rtne is just _mesa_float_to_half(). */
124
TEST(float_to_float16_rtz_test,float_to_float16_rtz_test)125 TEST(float_to_float16_rtz_test, float_to_float16_rtz_test)
126 {
127 test_float_to_half_limits(_mesa_float_to_float16_rtz);
128 }
129
TEST(float_to_float16_rtz_slow_test,float_to_float16_rtz_test)130 TEST(float_to_float16_rtz_slow_test, float_to_float16_rtz_test)
131 {
132 test_float_to_half_limits(_mesa_float_to_float16_rtz_slow);
133 }
134