xref: /minix/lib/libc/arch/aarch64/softfloat/qp.c (revision 0a6a1f1d)
1 /* $NetBSD: qp.c,v 1.1 2014/08/10 05:47:37 matt Exp $ */
2 
3 /*-
4  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Matt Thomas of 3am Software Foundry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 
33 #include "milieu.h"
34 #include "softfloat.h"
35 
36 /*
37  * This file provides wrappers for the softfloat functions.  We can't use
38  * invoke them directly since long double arguments are passed in FP/SIMD
39  * as well as being returned in them while float128 arguments are passed
40  * in normal registers.
41  */
42 
43 long double __addtf3(long double, long double);
44 long double __divtf3(long double, long double);
45 long double __modtf3(long double, long double);
46 long double __multf3(long double, long double);
47 long double __negtf2(long double);
48 long double __subtf3(long double, long double);
49 
50 int __getf2(long double, long double);
51 int __lttf2(long double, long double);
52 int __gttf2(long double, long double);
53 int __letf2(long double, long double);
54 int __eqtf2(long double, long double);
55 int __netf2(long double, long double);
56 int __unordtf2(long double, long double);
57 
58 double __trunctfdf2(long double);
59 float __trunctfsf2(long double);
60 
61 long double __extendsftf2(float);
62 long double __extenddftf2(double);
63 
64 long double __floatsitf(int32_t);
65 long double __floatditf(int64_t);
66 
67 long double __floatunsitf(uint32_t);
68 long double __floatunditf(uint64_t);
69 
70 int32_t __fixtfsi(long double);
71 int64_t __fixtfdi(long double);
72 
73 uint32_t __fixuntfsi(long double);
74 uint64_t __fixuntfdi(long double);
75 
76 #if 0
77 long double __floattitf(int128_t);
78 long double __floatuntitf(uint128_t);
79 int128_t __fixtfti(long double);
80 uint128_t __fixuntfti(long double);
81 #endif
82 
83 union sf_ieee_flt_u {
84 	float fltu_f;
85 	float32 fltu_f32;
86 };
87 
88 union sf_ieee_dbl_u {
89 	double dblu_d;
90 	float64 dblu_f64;
91 };
92 
93 union sf_ieee_ldbl_u {
94 	long double ldblu_ld;
95 	float128 ldblu_f128;
96 };
97 
98 long double
__addtf3(long double ld_a,long double ld_b)99 __addtf3(long double ld_a, long double ld_b)
100 {
101 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
102 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
103 	const union sf_ieee_ldbl_u c = {
104 	    .ldblu_f128 = float128_add(a.ldblu_f128, b.ldblu_f128)
105 	};
106 
107 	return c.ldblu_ld;
108 }
109 
110 long double
__divtf3(long double ld_a,long double ld_b)111 __divtf3(long double ld_a, long double ld_b)
112 {
113 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
114 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
115 	const union sf_ieee_ldbl_u c = {
116 	    .ldblu_f128 = float128_div(a.ldblu_f128, b.ldblu_f128)
117 	};
118 
119 	return c.ldblu_ld;
120 }
121 
122 long double
__multf3(long double ld_a,long double ld_b)123 __multf3(long double ld_a, long double ld_b)
124 {
125 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
126 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
127 	const union sf_ieee_ldbl_u c = {
128 	    .ldblu_f128 = float128_mul(a.ldblu_f128, b.ldblu_f128)
129 	};
130 
131 	return c.ldblu_ld;
132 }
133 
134 long double
__negtf2(long double ld_a)135 __negtf2(long double ld_a)
136 {
137 	const union sf_ieee_ldbl_u zero = { .ldblu_ld = 0.0 };
138 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
139 	const union sf_ieee_ldbl_u b = {
140 	    .ldblu_f128 = float128_div(zero.ldblu_f128, a.ldblu_f128)
141 	};
142 
143 	return b.ldblu_ld;
144 }
145 
146 long double
__subtf3(long double ld_a,long double ld_b)147 __subtf3(long double ld_a, long double ld_b)
148 {
149 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
150 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
151 	const union sf_ieee_ldbl_u c = {
152 	    .ldblu_f128 = float128_sub(a.ldblu_f128, b.ldblu_f128)
153 	};
154 
155 	return c.ldblu_ld;
156 }
157 
158 #if 0
159 int
160 __cmptf3(float128 *a, float128 *b)
161 {
162 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
163 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
164 
165 	if (float128_eq(*a, *b))
166 		return 0;
167 
168 	if (float128_le(*a, *b))
169 		return 1;
170 
171 	return 2;
172 }
173 
174 
175 /*
176  * XXX
177  */
178 int
179 _Qp_cmpe(float128 *a, float128 *b)
180 {
181 	return _Qp_cmp(a, b);
182 }
183 #endif
184 
185 int
__eqtf2(long double ld_a,long double ld_b)186 __eqtf2(long double ld_a, long double ld_b)
187 {
188 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
189 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
190 
191 	return float128_eq(a.ldblu_f128, b.ldblu_f128);
192 }
193 
194 int
__getf2(long double ld_a,long double ld_b)195 __getf2(long double ld_a, long double ld_b)
196 {
197 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
198 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
199 
200 	return float128_le(b.ldblu_f128, a.ldblu_f128);
201 }
202 
203 int
__gttf2(long double ld_a,long double ld_b)204 __gttf2(long double ld_a, long double ld_b)
205 {
206 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
207 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
208 
209 	return float128_lt(b.ldblu_f128, a.ldblu_f128);
210 }
211 
212 int
__letf2(long double ld_a,long double ld_b)213 __letf2(long double ld_a, long double ld_b)
214 {
215 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
216 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
217 
218 	return float128_le(a.ldblu_f128, b.ldblu_f128);
219 }
220 
221 int
__lttf2(long double ld_a,long double ld_b)222 __lttf2(long double ld_a, long double ld_b)
223 {
224 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
225 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
226 
227 	return float128_lt(a.ldblu_f128, b.ldblu_f128);
228 }
229 
230 int
__netf2(long double ld_a,long double ld_b)231 __netf2(long double ld_a, long double ld_b)
232 {
233 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
234 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
235 
236 	return !float128_eq(a.ldblu_f128, b.ldblu_f128);
237 }
238 
239 float
__trunctfsf2(long double ld_a)240 __trunctfsf2(long double ld_a)
241 {
242 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
243 	const union sf_ieee_flt_u c = {
244 		.fltu_f32 = float128_to_float32(a.ldblu_f128),
245 	};
246 
247 	return c.fltu_f;
248 }
249 
250 double
__trunctfdf2(long double ld_a)251 __trunctfdf2(long double ld_a)
252 {
253 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
254 	const union sf_ieee_dbl_u c = {
255 		.dblu_f64 = float128_to_float64(a.ldblu_f128),
256 	};
257 
258 	return c.dblu_d;
259 }
260 
261 int32_t
__fixtfsi(long double ld_a)262 __fixtfsi(long double ld_a)
263 {
264 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
265 	return float128_to_int32_round_to_zero(a.ldblu_f128);
266 }
267 
268 int64_t
__fixtfdi(long double ld_a)269 __fixtfdi(long double ld_a)
270 {
271 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
272 
273 	return float128_to_int64_round_to_zero(a.ldblu_f128);
274 }
275 
276 #if 0
277 uint32_t
278 __fixuntfsi(long double ld_a)
279 {
280 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
281 
282 	return float128_to_uint32_round_to_zero(a.ldblu_f128);
283 }
284 
285 uint64_t
286 __fixuntfdi(long double ld_a)
287 {
288 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
289 
290 	return float128_to_uint64_round_to_zero(a.ldblu_f128);
291 }
292 #endif
293 
294 long double
__extendsftf2(float f_a)295 __extendsftf2(float f_a)
296 {
297 	const union sf_ieee_flt_u a = { .fltu_f = f_a };
298 	const union sf_ieee_ldbl_u c = {
299 		.ldblu_f128 = float32_to_float128(a.fltu_f32)
300 	};
301 
302 	return c.ldblu_ld;
303 }
304 
305 long double
__extenddftf2(double d_a)306 __extenddftf2(double d_a)
307 {
308 	const union sf_ieee_dbl_u a = { .dblu_d = d_a };
309 	const union sf_ieee_ldbl_u c = {
310 		.ldblu_f128 = float64_to_float128(a.dblu_f64)
311 	};
312 
313 	return c.ldblu_ld;
314 }
315 
316 long double
__floatunsitf(uint32_t a)317 __floatunsitf(uint32_t a)
318 {
319 	const union sf_ieee_ldbl_u c = {
320 		.ldblu_f128 = int64_to_float128(a)
321 	};
322 
323 	return c.ldblu_ld;
324 }
325 
326 long double
__floatunditf(uint64_t a)327 __floatunditf(uint64_t a)
328 {
329 	union sf_ieee_ldbl_u c;
330 	const uint64_t msb64 = 1LL << 63;
331 
332 	if (a & msb64) {
333 		static const union sf_ieee_ldbl_u two63 = {
334 			.ldblu_ld = 0x1.0p63
335 		};
336 
337 		c.ldblu_f128 = int64_to_float128(a ^ msb64);
338 		c.ldblu_f128 = float128_add(c.ldblu_f128, two63.ldblu_f128);
339 	} else {
340 		c.ldblu_f128 = int64_to_float128(a);
341 	}
342 	return c.ldblu_ld;
343 }
344 
345 long double
__floatsitf(int32_t a)346 __floatsitf(int32_t a)
347 {
348 	const union sf_ieee_ldbl_u c = {
349 		.ldblu_f128 = int64_to_float128(a)
350 	};
351 
352 	return c.ldblu_ld;
353 }
354 
355 long double
__floatditf(int64_t a)356 __floatditf(int64_t a)
357 {
358 	const union sf_ieee_ldbl_u c = {
359 		.ldblu_f128 = int64_to_float128(a)
360 	};
361 
362 	return c.ldblu_ld;
363 }
364 
365 int
__unordtf2(long double ld_a,long double ld_b)366 __unordtf2(long double ld_a, long double ld_b)
367 {
368 	const union sf_ieee_ldbl_u a = { .ldblu_ld = ld_a };
369 	const union sf_ieee_ldbl_u b = { .ldblu_ld = ld_b };
370 
371 	/*
372 	 * The comparison is unordered if either input is a NaN.
373 	 * Test for this by comparing each operand with itself.
374 	 * We must perform both comparisons to correctly check for
375 	 * signalling NaNs.
376 	 */
377 	return 1 ^ (float128_eq(a.ldblu_f128, a.ldblu_f128) & float128_eq(b.ldblu_f128, b.ldblu_f128));
378 }
379