ReactOS 0.4.16-dev-91-g764881a
floatconv.c
Go to the documentation of this file.
1/*
2 * PROJECT: ReactOS API tests
3 * LICENSE: MIT (https://spdx.org/licenses/MIT)
4 * PURPOSE: Test for floating point conversion
5 * COPYRIGHT: Copyright 2024 Timo Kreuzer <timo.kreuzer@reactos.org>
6 */
7
8#include <apitest.h>
9
10/* Note: There are 2 behaviors for float to unsigned integer conversion:
11 * 1. The old behavior, which exists only on x86 and CL versions up to somewhere
12 * between 19.40.33811 and 19.41.33923:
13 * - If a negative float is cast to an unsigned integer, the result is ULONG_MAX
14 * for uint32 and ULLONG_MAX for uint64.
15 * - If a float is cast to an unsigned long and the value is larger than ULONG_MAX,
16 * the result is ULONG_MAX.
17 * 2. The new behavior (all x64 and x86 versions after the ones mentioned above):
18 * - If a negative float is cast to an unsigned integer, the result is the same as
19 first casting to the signed type, then casting to the unsigned type.
20 * - If a float is cast to an unsigned integer and the value is too large for the type,
21 * the result is 0 for uint32 and 0x8000000000000000 for uint64.
22 * In the old version, the float to unsigned conversion was inlined and used _ftoul2 and
23 * a comparison against 0x43e0000000000000 (9223372036854775808.0) to check for overflow.
24 * In the new version, the float to unsigned conversion is done by a call to _ftoul2_legacy,
25 * which checks for overflow by comparing against 0x5f800000 (18446744073709551616.0) and
26 * then forwards the call to either _ftol2 or _ftoul2.
27 */
28
29#if defined(_M_IX86) && defined(__VS_PROJECT__) && (_MSC_FULL_VER < 194133923)
30#define OLD_BEHAVIOR
31#endif
32
33#ifdef OLD_BEHAVIOR
34#define ULONG_OVERFLOW ULONG_MAX
35#define ULONGLONG_OVERFLOW ULLONG_MAX
36#else
37#define ULONG_OVERFLOW 0ul
38#define ULONGLONG_OVERFLOW 0x8000000000000000ull
39#endif
40
41#ifdef __GNUC__
42#define todo_gcc todo_ros
43#else
44#define todo_gcc
45#endif
46
48long cast_float_to_long(float f)
49{
50 return (long)f;
51}
52
54unsigned long cast_float_to_ulong(float f)
55{
56 return (unsigned long)f;
57}
58
60long cast_double_to_long(double d)
61{
62 return (long)d;
63}
64
66unsigned long cast_double_to_ulong(double d)
67{
68 return (unsigned long)d;
69}
70
72long long cast_float_to_longlong(float f)
73{
74 return (long long)f;
75}
76
78unsigned long long cast_float_to_ulonglong(float f)
79{
80 return (unsigned long long)f;
81}
82
84long long cast_double_to_longlong(double d)
85{
86 return (long long)d;
87}
88
90unsigned long long cast_double_to_ulonglong(double d)
91{
92 return (unsigned long long)d;
93}
94
95void Test_float(void)
96{
97 // float to long cast
98 ok_eq_long(cast_float_to_long(0.0f), 0l);
99 ok_eq_long(cast_float_to_long(1.0f), 1l);
100 ok_eq_long(cast_float_to_long(-1.0f), -1l);
101 ok_eq_long(cast_float_to_long(0.5f), 0l);
102 ok_eq_long(cast_float_to_long(-0.5f), 0l);
103 ok_eq_long(cast_float_to_long(0.999999f), 0l);
104 ok_eq_long(cast_float_to_long(-0.999999f), 0l);
105 ok_eq_long(cast_float_to_long(2147483500.0f), 2147483520l);
106 ok_eq_long(cast_float_to_long(2147483583.999f), 2147483520l);
107 ok_eq_long(cast_float_to_long(-2147483583.999f), -2147483520l);
108 ok_eq_long(cast_float_to_long(2147483584.0f), LONG_MIN); // -2147483648
109 ok_eq_long(cast_float_to_long(2147483648.0f), LONG_MIN); // -2147483648
110 ok_eq_long(cast_float_to_long(-2147483648.0f), LONG_MIN); // -2147483648
111 ok_eq_long(cast_float_to_long(10000000000.0f), LONG_MIN);
112 ok_eq_long(cast_float_to_long(-10000000000.0f), LONG_MIN);
113
114 // float to unsigned long cast (positive values)
115 ok_eq_ulong(cast_float_to_ulong(0.0f), 0ul);
116 ok_eq_ulong(cast_float_to_ulong(1.0f), 1ul);
117 ok_eq_ulong(cast_float_to_ulong(0.5f), 0ul);
118 ok_eq_ulong(cast_float_to_ulong(0.999999f), 0ul);
119 ok_eq_ulong(cast_float_to_ulong(2147483648.0f), 2147483648ul); // 0x80000000
120 ok_eq_ulong(cast_float_to_ulong(4294967150.0f), 4294967040ul); // 0xFFFFFF00
121 ok_eq_ulong(cast_float_to_ulong(4294967294.0f), ULONG_OVERFLOW);
122
123 // float to unsigned long cast (negative values)
124 ok_eq_ulong(cast_float_to_ulong(-0.0f), 0ul);
125 ok_eq_ulong(cast_float_to_ulong(-0.5f), 0ul);
126 ok_eq_ulong(cast_float_to_ulong(-1.0f), ULONG_MAX);
127#ifdef OLD_BEHAVIOR
128 ok_eq_ulong(cast_float_to_ulong(-10.0f), ULONG_MAX);
129 ok_eq_ulong(cast_float_to_ulong(-1147483648.0f), ULONG_MAX);
130 ok_eq_ulong(cast_float_to_ulong(-2147483648.0f), ULONG_MAX);
131#else
132 ok_eq_ulong(cast_float_to_ulong(-10.0f), (unsigned long)-10);
133 ok_eq_ulong(cast_float_to_ulong(-1147483648.0f), (unsigned long)-1147483648ll);
134 ok_eq_ulong(cast_float_to_ulong(-2147483648.0f), (unsigned long)-2147483648ll);
135#endif
136
137 // float to long long cast
138 ok_eq_longlong(cast_float_to_longlong(0.0f), 0ll);
139 ok_eq_longlong(cast_float_to_longlong(1.0f), 1ll);
140 ok_eq_longlong(cast_float_to_longlong(-1.0f), -1ll);
141 ok_eq_longlong(cast_float_to_longlong(0.5f), 0ll);
142 ok_eq_longlong(cast_float_to_longlong(-0.5f), 0ll);
143 ok_eq_longlong(cast_float_to_longlong(0.999999f), 0ll);
144 ok_eq_longlong(cast_float_to_longlong(-0.999999f), 0ll);
145 ok_eq_longlong(cast_float_to_longlong(9223371761976868863.9999f), 9223371487098961920ll);
146 ok_eq_longlong(cast_float_to_longlong(9223371761976868864.0f), LLONG_MIN);
147 ok_eq_longlong(cast_float_to_longlong(-9223371761976868863.9999f), -9223371487098961920ll);
148 ok_eq_longlong(cast_float_to_longlong(-9223371761976868864.0f), LLONG_MIN);
149 ok_eq_longlong(cast_float_to_longlong(100000000000000000000.0f), LLONG_MIN);
150 ok_eq_longlong(cast_float_to_longlong(-100000000000000000000.0f), LLONG_MIN);
151
152 // float to unsigned long long cast (positive values)
153 ok_eq_ulonglong(cast_float_to_ulonglong(0.0f), 0ull);
154 ok_eq_ulonglong(cast_float_to_ulonglong(1.0f), 1ull);
155 ok_eq_ulonglong(cast_float_to_ulonglong(0.5f), 0ull);
156 ok_eq_ulonglong(cast_float_to_ulonglong(0.999999f), 0ull);
157 ok_eq_ulonglong(cast_float_to_ulonglong(9223371487098961920.0f), 9223371487098961920ull); // 0x7FFFFF8000000000
158 ok_eq_ulonglong(cast_float_to_ulonglong(9223372036854775808.0f), 9223372036854775808ull); // 0x8000000000000000
159 ok_eq_ulonglong(cast_float_to_ulonglong(18446743523953737727.9f), 18446742974197923840ull); // 0xFFFFFF0000000000
160 todo_gcc ok_eq_ulonglong(cast_float_to_ulonglong(18446743523953737728.0f), ULONGLONG_OVERFLOW); // 0x8000000000000000 / 0xFFFFFFFFFFFFFFFF
161 todo_gcc ok_eq_ulonglong(cast_float_to_ulonglong(20000000000000000000.0f), ULONGLONG_OVERFLOW); // 0x8000000000000000 / 0xFFFFFFFFFFFFFFFF
162
163 // float to unsigned long long cast (negative values)
164 ok_eq_ulonglong(cast_float_to_ulonglong(-0.0f), 0ull);
165 ok_eq_ulonglong(cast_float_to_ulonglong(-0.5f), 0ull);
166 ok_eq_ulonglong(cast_float_to_ulonglong(-1.0f), 18446744073709551615ull);
167#ifdef OLD_BEHAVIOR
168 ok_eq_ulonglong(cast_float_to_ulonglong(-10.0f), ULLONG_MAX);
169 ok_eq_ulonglong(cast_float_to_ulonglong(-1147483648.0f), ULLONG_MAX);
170 ok_eq_ulonglong(cast_float_to_ulonglong(-2147483648.0f), ULLONG_MAX);
171 ok_eq_ulonglong(cast_float_to_ulonglong(-9223371761976868863.9f), ULLONG_MAX);
172 ok_eq_ulonglong(cast_float_to_ulonglong(-9223371761976868864.0f), ULLONG_MAX);
173 ok_eq_ulonglong(cast_float_to_ulonglong(-9223372036854775808.0f), ULLONG_MAX);
174#else
175 ok_eq_ulonglong(cast_float_to_ulonglong(-10.0f), (unsigned long long)-10);
176 ok_eq_ulonglong(cast_float_to_ulonglong(-1147483648.0f), (unsigned long long)-1147483648ll);
177 ok_eq_ulonglong(cast_float_to_ulonglong(-2147483648.0f), (unsigned long long)-2147483648ll);
178 ok_eq_ulonglong(cast_float_to_ulonglong(-9223371761976868863.9f), (unsigned long long)-9223371487098961920);
179 ok_eq_ulonglong(cast_float_to_ulonglong(-9223371761976868864.0f), (unsigned long long)(-9223372036854775807ll - 1)); // 0x8000000000000000 / ULONGLONG_OVERFLOW
180 ok_eq_ulonglong(cast_float_to_ulonglong(-9223372036854775808.0f), (unsigned long long)(-9223372036854775807ll - 1)); // 0x8000000000000000 / ULONGLONG_OVERFLOW
181#endif
182 ok_eq_ulonglong(cast_float_to_ulonglong(-100000000000000000000.0f), ULONGLONG_OVERFLOW);
183}
184
185void Test_double(void)
186{
187 // double to long cast
188 ok_eq_long(cast_double_to_long(0.0), 0l);
189 ok_eq_long(cast_double_to_long(1.0), 1l);
190 ok_eq_long(cast_double_to_long(-1.0), -1l);
191 ok_eq_long(cast_double_to_long(0.5), 0l);
192 ok_eq_long(cast_double_to_long(-0.5), 0l);
193 ok_eq_long(cast_double_to_long(0.999999999), 0l);
194 ok_eq_long(cast_double_to_long(-0.999999999), 0l);
195 ok_eq_long(cast_double_to_long(2147483647.99999), 2147483647l);
196 ok_eq_long(cast_double_to_long(-2147483647.99999), -2147483647l);
197 ok_eq_long(cast_double_to_long(2147483648.0), LONG_MIN); // -2147483648
198 ok_eq_long(cast_double_to_long(-2147483648.0), LONG_MIN); // -2147483648
199 ok_eq_long(cast_double_to_long(10000000000.0), LONG_MIN);
200 ok_eq_long(cast_double_to_long(-10000000000.0), LONG_MIN);
201
202 // double to unsigned long cast (positive values)
203 ok_eq_ulong(cast_double_to_ulong(0.0), 0ul);
204 ok_eq_ulong(cast_double_to_ulong(1.0), 1ul);
205 ok_eq_ulong(cast_double_to_ulong(0.5), 0ul);
206 ok_eq_ulong(cast_double_to_ulong(0.999999999), 0ul);
207 ok_eq_ulong(cast_double_to_ulong(2147483648.0), 2147483648ul); // 0x80000000
208 ok_eq_ulong(cast_double_to_ulong(4294967295.0), 4294967295ul); // 0xFFFFFFFF
209 ok_eq_ulong(cast_double_to_ulong(4294967296.0), ULONG_OVERFLOW);
210
211 // double to unsigned long cast (negative values)
212 ok_eq_ulong(cast_double_to_ulong(-0.0), 0ul);
213 ok_eq_ulong(cast_double_to_ulong(-0.5), 0ul);
214 ok_eq_ulong(cast_double_to_ulong(-1.0), ULONG_MAX);
215#ifdef OLD_BEHAVIOR
216 ok_eq_ulong(cast_double_to_ulong(-10.0), ULONG_MAX);
217 ok_eq_ulong(cast_double_to_ulong(-1147483648.0), ULONG_MAX);
218 ok_eq_ulong(cast_double_to_ulong(-2147483648.0), ULONG_MAX);
219#else
220 ok_eq_ulong(cast_double_to_ulong(-10.0), (unsigned long)-10);
221 ok_eq_ulong(cast_double_to_ulong(-1147483648.0), (unsigned long)-1147483648ll);
222 ok_eq_ulong(cast_double_to_ulong(-2147483648.0), (unsigned long)-2147483648ll);
223#endif
224
225 // double to long long cast
226 ok_eq_longlong(cast_double_to_longlong(0.0), 0ll);
227 ok_eq_longlong(cast_double_to_longlong(1.0), 1ll);
228 ok_eq_longlong(cast_double_to_longlong(-1.0), -1ll);
229 ok_eq_longlong(cast_double_to_longlong(0.5), 0ll);
230 ok_eq_longlong(cast_double_to_longlong(-0.5), 0ll);
231 ok_eq_longlong(cast_double_to_longlong(0.999999), 0ll);
232 ok_eq_longlong(cast_double_to_longlong(-0.999999), 0ll);
233 ok_eq_longlong(cast_double_to_longlong(9223372036854775295.9), 9223372036854774784ll);
234 ok_eq_longlong(cast_double_to_longlong(9223372036854775296.0), LLONG_MIN);
235 ok_eq_longlong(cast_double_to_longlong(-9223372036854775295.9), -9223372036854774784ll);
236 ok_eq_longlong(cast_double_to_longlong(-9223372036854775296.0), LLONG_MIN);
237 ok_eq_longlong(cast_double_to_longlong(100000000000000000000.0), LLONG_MIN);
238 ok_eq_longlong(cast_double_to_longlong(-100000000000000000000.0), LLONG_MIN);
239
240 // double to unsigned long long cast (positive values)
241 ok_eq_ulonglong(cast_double_to_ulonglong(0.0), 0ull);
242 ok_eq_ulonglong(cast_double_to_ulonglong(1.0), 1ull);
243 ok_eq_ulonglong(cast_double_to_ulonglong(0.5), 0ull);
244 ok_eq_ulonglong(cast_double_to_ulonglong(0.999999), 0ull);
245 ok_eq_ulonglong(cast_double_to_ulonglong(9223372036854774784.0), 9223372036854774784ull); // 0x7FFFFFFFFFFFFC00
246 ok_eq_ulonglong(cast_double_to_ulonglong(9223372036854775808.0), 9223372036854775808ull); // 0x8000000000000000
247 ok_eq_ulonglong(cast_double_to_ulonglong(18446744073709550591.9), 18446744073709549568ull); // 0xFFFFFFFFFFFFF800
248 todo_gcc ok_eq_ulonglong(cast_double_to_ulonglong(18446744073709550592.0), ULONGLONG_OVERFLOW); // 0x8000000000000000 / 0xFFFFFFFFFFFFFFFF
249 todo_gcc ok_eq_ulonglong(cast_double_to_ulonglong(18446744073709551616.0), ULONGLONG_OVERFLOW); // 0x8000000000000000 / 0xFFFFFFFFFFFFFFFF
250 todo_gcc ok_eq_ulonglong(cast_double_to_ulonglong(20000000000000000000.0), ULONGLONG_OVERFLOW); // 0x8000000000000000 / 0xFFFFFFFFFFFFFFFF
251
252 // float to unsigned long long cast (negative values)
253 ok_eq_ulonglong(cast_double_to_ulonglong(-0.0), 0ull);
254 ok_eq_ulonglong(cast_double_to_ulonglong(-0.5), 0ull);
255 ok_eq_ulonglong(cast_double_to_ulonglong(-1.0), 18446744073709551615ull);
256#ifdef OLD_BEHAVIOR
257 ok_eq_ulonglong(cast_double_to_ulonglong(-10.0), ULLONG_MAX);
258 ok_eq_ulonglong(cast_double_to_ulonglong(-1147483648.0), ULLONG_MAX);
259 ok_eq_ulonglong(cast_double_to_ulonglong(-2147483648.0), ULLONG_MAX);
260 ok_eq_ulonglong(cast_double_to_ulonglong(-9223371761976868863.9), ULLONG_MAX);
261 ok_eq_ulonglong(cast_double_to_ulonglong(-9223371761976868864.0), ULLONG_MAX);
262 ok_eq_ulonglong(cast_double_to_ulonglong(-9223372036854775808.0), ULLONG_MAX);
263#else
264 ok_eq_ulonglong(cast_double_to_ulonglong(-10.0), (unsigned long long)-10);
265 ok_eq_ulonglong(cast_double_to_ulonglong(-1147483648.0), (unsigned long long)-1147483648ll);
266 ok_eq_ulonglong(cast_double_to_ulonglong(-2147483648.0), (unsigned long long)-2147483648ll);
267 ok_eq_ulonglong(cast_double_to_ulonglong(-9223372036854775000.0), (unsigned long long)-9223372036854774784ll);
268 ok_eq_ulonglong(cast_double_to_ulonglong(-9223372036854775808.0), (unsigned long long)(-9223372036854775807ll - 1));
269#endif
270 ok_eq_ulonglong(cast_double_to_ulonglong(-100000000000000000000.0), ULONGLONG_OVERFLOW);
271}
272
273START_TEST(floatconv)
274{
275 Test_float();
276 Test_double();
277}
#define ok_eq_ulong(value, expected)
Definition: apitest.h:63
#define ok_eq_longlong(value, expected)
Definition: apitest.h:64
#define ok_eq_long(value, expected)
Definition: apitest.h:62
#define ok_eq_ulonglong(value, expected)
Definition: apitest.h:65
#define START_TEST(x)
Definition: atltest.h:75
w ll
Definition: byte_order.h:167
r l[0]
Definition: byte_order.h:168
#define noinline
Definition: types.h:64
#define ULONG_OVERFLOW
Definition: floatconv.c:37
#define todo_gcc
Definition: floatconv.c:44
void Test_float(void)
Definition: floatconv.c:95
__declspec(noinline)
Definition: floatconv.c:47
#define ULONGLONG_OVERFLOW
Definition: floatconv.c:38
void Test_double(void)
Definition: floatconv.c:185
GLfloat f
Definition: glext.h:7540
#define ULONG_MAX
Definition: limits.h:44
#define ULLONG_MAX
Definition: limits.h:47
#define LONG_MIN
Definition: limits.h:42
#define LLONG_MIN
Definition: limits.h:46
#define d
Definition: ke_i.h:81
#define f
Definition: ke_i.h:83