xref: /openbsd-src/regress/lib/libm/msun/fenv_test.c (revision 4e1ee0786f11cc571bd0be17d38e46f635c719fc)
1 /*	$OpenBSD: fenv_test.c,v 1.6 2021/10/22 18:00:22 mbuhl Exp $	*/
2 /*-
3  * Copyright (c) 2004 David Schultz <das@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include "macros.h"
29 
30 /*
31  * Test the correctness and C99-compliance of various fenv.h features.
32  */
33 
34 #include <sys/cdefs.h>
35 /* $FreeBSD: head/lib/msun/tests/fenv_test.c 314650 2017-03-04 10:07:46Z ngie $ */
36 
37 #include <sys/types.h>
38 #include <sys/wait.h>
39 #include <assert.h>
40 #include <err.h>
41 #include <fenv.h>
42 #include <float.h>
43 #ifndef __OpenBSD__
44 #include <libutil.h>
45 #endif
46 #include <math.h>
47 #include <signal.h>
48 #include <stdio.h>
49 #include <string.h>
50 #include <unistd.h>
51 
52 #include "test-utils.h"
53 
54 #define	NEXCEPTS	(sizeof(std_excepts) / sizeof(std_excepts[0]))
55 
56 static const int std_excepts[] = {
57 	FE_INVALID,
58 	FE_DIVBYZERO,
59 	FE_OVERFLOW,
60 	FE_UNDERFLOW,
61 	FE_INEXACT,
62 };
63 
64 /* init_exceptsets() initializes this to the power set of std_excepts[] */
65 static int std_except_sets[1 << NEXCEPTS];
66 
67 #pragma STDC FENV_ACCESS ON
68 
69 /*
70  * Initialize std_except_sets[] to the power set of std_excepts[]
71  */
72 static __attribute__((constructor)) void
73 do_setup(void)
74 {
75 	unsigned i, j, sr;
76 
77 	/* Avoid double output after fork() */
78 	setvbuf(stdout, NULL, _IONBF, 0);
79 
80 	for (i = 0; i < 1 << NEXCEPTS; i++) {
81 		for (sr = i, j = 0; sr != 0; sr >>= 1, j++)
82 			std_except_sets[i] |= std_excepts[j] & ((~sr & 1) - 1);
83 	}
84 }
85 
86 /*
87  * Raise a floating-point exception without relying on the standard
88  * library routines, which we are trying to test.
89  *
90  * XXX We can't raise an {over,under}flow without also raising an
91  * inexact exception.
92  */
93 static void
94 raiseexcept(int excepts)
95 {
96 	volatile double d;
97 
98 	/*
99 	 * With a compiler that supports the FENV_ACCESS pragma
100 	 * properly, simple expressions like '0.0 / 0.0' should
101 	 * be sufficient to generate traps.  Unfortunately, we
102 	 * need to bring a volatile variable into the equation
103 	 * to prevent incorrect optimizations.
104 	 */
105 	if (excepts & FE_INVALID) {
106 		d = 0.0;
107 		d = 0.0 / d;
108 	}
109 	if (excepts & FE_DIVBYZERO) {
110 		d = 0.0;
111 		d = 1.0 / d;
112 	}
113 	if (excepts & FE_OVERFLOW) {
114 		d = DBL_MAX;
115 		d *= 2.0;
116 	}
117 	if (excepts & FE_UNDERFLOW) {
118 		d = DBL_MIN;
119 		d /= DBL_MAX;
120 	}
121 	if (excepts & FE_INEXACT) {
122 		d = DBL_MIN;
123 		d += 1.0;
124 	}
125 
126 	/*
127 	 * On the x86 (and some other architectures?) the FPU and
128 	 * integer units are decoupled.  We need to execute an FWAIT
129 	 * or a floating-point instruction to get synchronous exceptions.
130 	 */
131 	d = 1.0;
132 	d += 1.0;
133 }
134 
135 /*
136  * Determine the current rounding mode without relying on the fenv
137  * routines.  This function may raise an inexact exception.
138  */
139 static int
140 getround(void)
141 {
142 	volatile double d, e;
143 
144 	/*
145 	 * This test works just as well with 0.0 - 0.0, except on ia64
146 	 * where 0.0 - 0.0 gives the wrong sign when rounding downwards.
147 	 * For ia32 use a volatile double to force 64 bit rounding.
148 	 * Otherwise the i387 would use its internal 80 bit stack.
149 	 */
150 	d = 1.0;
151 	d -= 1.0;
152 	if (copysign(1.0, d) < 0.0)
153 		return (FE_DOWNWARD);
154 
155 	d = 1.0;
156 	e = d + (DBL_EPSILON * 3.0 / 4.0);
157 	if (e == 1.0)
158 		return (FE_TOWARDZERO);
159 	e = d + (DBL_EPSILON * 1.0 / 4.0);
160 	if (e > 1.0)
161 		return (FE_UPWARD);
162 
163 	return (FE_TONEAREST);
164 }
165 
166 static void
167 trap_handler(int sig)
168 {
169 
170 	ATF_CHECK_EQ(SIGFPE, sig);
171 	_exit(0);
172 }
173 
174 /*
175  * This tests checks the default FP environment, so it must be first.
176  * The memcmp() test below may be too much to ask for, since there
177  * could be multiple machine-specific default environments.
178  */
179 ATF_TC_WITHOUT_HEAD(dfl_env);
180 ATF_TC_BODY(dfl_env, tc)
181 {
182 #ifndef NO_STRICT_DFL_ENV
183 	fenv_t env;
184 
185 	fegetenv(&env);
186 	/* Print the default environment for debugging purposes. */
187 	hexdump(&env, sizeof(env), "current fenv ", HD_OMIT_CHARS);
188 	hexdump(FE_DFL_ENV, sizeof(env), "default fenv ", HD_OMIT_CHARS);
189 	CHECK_FP_EXCEPTIONS(0, FE_ALL_EXCEPT);
190 #ifdef __amd64__
191 	/*
192 	 * Compare the fields that the AMD [1] and Intel [2] specs say will be
193 	 * set once fnstenv returns.
194 	 *
195 	 * Not all amd64 capable processors implement the fnstenv instruction
196 	 * by zero'ing out the env.__x87.__other field (example: AMD Opteron
197 	 * 6308). The AMD64/x64 specs aren't explicit on what the
198 	 * env.__x87.__other field will contain after fnstenv is executed, so
199 	 * the values in env.__x87.__other could be filled with arbitrary
200 	 * data depending on how the CPU implements fnstenv.
201 	 *
202 	 * 1. http://support.amd.com/TechDocs/26569_APM_v5.pdf
203 	 * 2. http://www.intel.com/Assets/en_US/PDF/manual/253666.pdf
204 	 */
205 	ATF_CHECK(memcmp(&env.__mxcsr, &FE_DFL_ENV->__mxcsr,
206 	    sizeof(env.__mxcsr)) == 0);
207 	ATF_CHECK(memcmp(&env.__x87.__control, &FE_DFL_ENV->__x87.__control,
208 	    sizeof(env.__x87.__control)) == 0);
209 	ATF_CHECK(memcmp(&env.__x87.__status, &FE_DFL_ENV->__x87.__status,
210 	    sizeof(env.__x87.__status)) == 0);
211 	ATF_CHECK(memcmp(&env.__x87.__tag, &FE_DFL_ENV->__x87.__tag,
212 	    sizeof(env.__x87.__tag)) == 0);
213 #else
214 	ATF_CHECK_EQ(0, memcmp(&env, FE_DFL_ENV, sizeof(env)));
215 #endif
216 
217 #endif
218 	CHECK_FP_EXCEPTIONS(0, FE_ALL_EXCEPT);
219 }
220 
221 /*
222  * Test fetestexcept() and feclearexcept().
223  */
224 ATF_TC_WITHOUT_HEAD(fetestclearexcept);
225 ATF_TC_BODY(fetestclearexcept, tc)
226 {
227 	int excepts, i;
228 
229 	for (i = 0; i < 1 << NEXCEPTS; i++)
230 		ATF_CHECK_EQ(0, fetestexcept(std_except_sets[i]));
231 	for (i = 0; i < 1 << NEXCEPTS; i++) {
232 		excepts = std_except_sets[i];
233 
234 		/* FE_ALL_EXCEPT might be special-cased, as on i386. */
235 		raiseexcept(excepts);
236 		ATF_CHECK_EQ(excepts, fetestexcept(excepts));
237 		ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
238 		ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
239 
240 		raiseexcept(excepts);
241 		ATF_CHECK_EQ(excepts, fetestexcept(excepts));
242 		if ((excepts & (FE_UNDERFLOW | FE_OVERFLOW)) != 0) {
243 			excepts |= FE_INEXACT;
244 			ATF_CHECK_EQ(excepts, (fetestexcept(ALL_STD_EXCEPT) | FE_INEXACT));
245 		} else {
246 			ATF_CHECK_EQ(excepts, fetestexcept(ALL_STD_EXCEPT));
247 		}
248 		ATF_CHECK_EQ(0, feclearexcept(excepts));
249 		ATF_CHECK_EQ(0, fetestexcept(ALL_STD_EXCEPT));
250 	}
251 }
252 
253 /*
254  * Test fegetexceptflag() and fesetexceptflag().
255  *
256  * Prerequisites: fetestexcept(), feclearexcept()
257  */
258 ATF_TC_WITHOUT_HEAD(fegsetexceptflag);
259 ATF_TC_BODY(fegsetexceptflag, tc)
260 {
261 	fexcept_t flag;
262 	int excepts, i;
263 
264 	CHECK_FP_EXCEPTIONS(0, FE_ALL_EXCEPT);
265 	for (i = 0; i < 1 << NEXCEPTS; i++) {
266 		excepts = std_except_sets[i];
267 
268 		ATF_CHECK_EQ(0, fegetexceptflag(&flag, excepts));
269 		raiseexcept(ALL_STD_EXCEPT);
270 		ATF_CHECK_EQ(0, fesetexceptflag(&flag, excepts));
271 		ATF_CHECK_EQ((ALL_STD_EXCEPT ^ excepts), fetestexcept(ALL_STD_EXCEPT));
272 
273 		ATF_CHECK_EQ(0, fegetexceptflag(&flag, FE_ALL_EXCEPT));
274 		ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
275 		ATF_CHECK_EQ(0, fesetexceptflag(&flag, excepts));
276 		ATF_CHECK_EQ(0, fetestexcept(ALL_STD_EXCEPT));
277 		ATF_CHECK_EQ(0, fesetexceptflag(&flag, ALL_STD_EXCEPT ^ excepts));
278 		ATF_CHECK_EQ((ALL_STD_EXCEPT ^ excepts), fetestexcept(ALL_STD_EXCEPT));
279 
280 		ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
281 	}
282 }
283 
284 /*
285  * Test feraiseexcept().
286  *
287  * Prerequisites: fetestexcept(), feclearexcept()
288  */
289 ATF_TC_WITHOUT_HEAD(feraiseexcept);
290 ATF_TC_BODY(feraiseexcept, tc)
291 {
292 	int excepts, i;
293 
294 	for (i = 0; i < 1 << NEXCEPTS; i++) {
295 		excepts = std_except_sets[i];
296 
297 		ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
298 		ATF_CHECK_EQ(0, feraiseexcept(excepts));
299 		if ((excepts & (FE_UNDERFLOW | FE_OVERFLOW)) != 0) {
300 			excepts |= FE_INEXACT;
301 			ATF_CHECK_EQ(excepts, (fetestexcept(ALL_STD_EXCEPT) | FE_INEXACT));
302 		} else {
303 			ATF_CHECK_EQ(excepts, fetestexcept(ALL_STD_EXCEPT));
304 		}
305 		ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
306 	}
307 	ATF_CHECK_EQ(0, feraiseexcept(FE_INVALID | FE_DIVBYZERO));
308 	ATF_CHECK_EQ((FE_INVALID | FE_DIVBYZERO), fetestexcept(ALL_STD_EXCEPT));
309 	ATF_CHECK_EQ(0, feraiseexcept(FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT));
310 	ATF_CHECK_EQ(ALL_STD_EXCEPT, fetestexcept(ALL_STD_EXCEPT));
311 	ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
312 }
313 
314 /*
315  * Test fegetround() and fesetround().
316  */
317 ATF_TC_WITHOUT_HEAD(fegsetround);
318 ATF_TC_BODY(fegsetround, tc)
319 {
320 
321 	ATF_CHECK_EQ(FE_TONEAREST, fegetround());
322 	ATF_CHECK_EQ(FE_TONEAREST, getround());
323 	ATF_CHECK_EQ(1, FLT_ROUNDS);
324 
325 	ATF_CHECK_EQ(0, fesetround(FE_DOWNWARD));
326 	ATF_CHECK_EQ(FE_DOWNWARD, fegetround());
327 	ATF_CHECK_EQ(FE_DOWNWARD, getround());
328 	ATF_CHECK_EQ(3, FLT_ROUNDS);
329 
330 	ATF_CHECK_EQ(0, fesetround(FE_UPWARD));
331 	ATF_CHECK_EQ(FE_UPWARD, getround());
332 	ATF_CHECK_EQ(FE_UPWARD, fegetround());
333 	ATF_CHECK_EQ(2, FLT_ROUNDS);
334 
335 	ATF_CHECK_EQ(0, fesetround(FE_TOWARDZERO));
336 	ATF_CHECK_EQ(FE_TOWARDZERO, getround());
337 	ATF_CHECK_EQ(FE_TOWARDZERO, fegetround());
338 	ATF_CHECK_EQ(0, FLT_ROUNDS);
339 
340 	ATF_CHECK_EQ(0, fesetround(FE_TONEAREST));
341 	ATF_CHECK_EQ(FE_TONEAREST, getround());
342 	ATF_CHECK_EQ(1, FLT_ROUNDS);
343 
344 	ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
345 }
346 
347 /*
348  * Test fegetenv() and fesetenv().
349  *
350  * Prerequisites: fetestexcept(), feclearexcept(), fegetround(), fesetround()
351  */
352 ATF_TC_WITHOUT_HEAD(fegsetenv);
353 ATF_TC_BODY(fegsetenv, tc)
354 {
355 	fenv_t env1, env2;
356 	int excepts, i;
357 
358 	for (i = 0; i < 1 << NEXCEPTS; i++) {
359 		excepts = std_except_sets[i];
360 
361 		ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
362 		ATF_CHECK_EQ(FE_TONEAREST, fegetround());
363 		ATF_CHECK_EQ(0, fegetenv(&env1));
364 
365 		/*
366 		 * fe[gs]etenv() should be able to save and restore
367 		 * exception flags without the spurious inexact
368 		 * exceptions that afflict raiseexcept().
369 		 */
370 		raiseexcept(excepts);
371 		if ((excepts & (FE_UNDERFLOW | FE_OVERFLOW)) != 0 &&
372 		    (excepts & FE_INEXACT) == 0)
373 			ATF_CHECK_EQ(0, feclearexcept(FE_INEXACT));
374 
375 		fesetround(FE_DOWNWARD);
376 		ATF_CHECK_EQ(0, fegetenv(&env2));
377 		ATF_CHECK_EQ(0, fesetenv(&env1));
378 		ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
379 		ATF_CHECK_EQ(FE_TONEAREST, fegetround());
380 
381 		ATF_CHECK_EQ(0, fesetenv(&env2));
382 
383 		/*
384 		 * Some platforms like powerpc may set extra exception bits. Since
385 		 * only standard exceptions are tested, mask against ALL_STD_EXCEPT
386 		 */
387 		ATF_CHECK_EQ(excepts, (fetestexcept(FE_ALL_EXCEPT) & ALL_STD_EXCEPT));
388 
389 		ATF_CHECK_EQ(FE_DOWNWARD, fegetround());
390 		ATF_CHECK_EQ(0, fesetenv(&env1));
391 		ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
392 		ATF_CHECK_EQ(FE_TONEAREST, fegetround());
393 	}
394 }
395 
396 /*
397  * Test fegetexcept(), fedisableexcept(), and feenableexcept().
398  *
399  * Prerequisites: fetestexcept(), feraiseexcept()
400  */
401 ATF_TC_WITHOUT_HEAD(masking);
402 ATF_TC_BODY(masking, tc)
403 {
404 #if !defined(__arm__) && !defined(__aarch64__) && !defined(__riscv)
405 	struct sigaction act;
406 	int except, pass, raise, status;
407 	unsigned i;
408 
409 	ATF_REQUIRE_EQ(0, (fegetexcept() & ALL_STD_EXCEPT));
410 
411 	/*
412 	 * Some CPUs, e.g. AArch64 QEMU does not support trapping on FP
413 	 * exceptions. In that case the trap enable bits are all RAZ/WI, so
414 	 * writing to those bits will be ignored and the the next read will
415 	 * return all zeroes for those bits. Skip the test if no floating
416 	 * point exceptions are supported and mark it XFAIL if some are missing.
417 	 */
418 	ATF_REQUIRE_EQ(0, (feenableexcept(FE_ALL_EXCEPT)));
419 	except = fegetexcept();
420 	if (except == 0) {
421 		atf_tc_skip("CPU does not support trapping on floating point "
422 		    "exceptions.");
423 	} else if ((except & ALL_STD_EXCEPT) != ALL_STD_EXCEPT) {
424 		atf_tc_expect_fail("Not all floating point exceptions can be "
425 		    "set to trap: %#x vs %#x", except, ALL_STD_EXCEPT);
426 	}
427 	fedisableexcept(FE_ALL_EXCEPT);
428 
429 
430 	ATF_CHECK_EQ(0, (feenableexcept(FE_INVALID|FE_OVERFLOW) & ALL_STD_EXCEPT));
431 	ATF_CHECK_EQ((FE_INVALID | FE_OVERFLOW), (feenableexcept(FE_UNDERFLOW) & ALL_STD_EXCEPT));
432 	ATF_CHECK_EQ((FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW), (fedisableexcept(FE_OVERFLOW) & ALL_STD_EXCEPT));
433 	ATF_CHECK_EQ((FE_INVALID | FE_UNDERFLOW), (fegetexcept() & ALL_STD_EXCEPT));
434 	ATF_CHECK_EQ((FE_INVALID | FE_UNDERFLOW), (fedisableexcept(FE_ALL_EXCEPT) & ALL_STD_EXCEPT));
435 	ATF_CHECK_EQ(0, (fegetexcept() & ALL_STD_EXCEPT));
436 
437 	sigemptyset(&act.sa_mask);
438 	act.sa_flags = 0;
439 	act.sa_handler = trap_handler;
440 	for (pass = 0; pass < 2; pass++) {
441 		for (i = 0; i < NEXCEPTS; i++) {
442 			except = std_excepts[i];
443 			/* over/underflow may also raise inexact */
444 			if (except == FE_INEXACT)
445 				raise = FE_DIVBYZERO | FE_INVALID;
446 			else
447 				raise = ALL_STD_EXCEPT ^ except;
448 
449 			/*
450 			 * We need to fork a child process because
451 			 * there isn't a portable way to recover from
452 			 * a floating-point exception.
453 			 */
454 			switch(fork()) {
455 			case 0:		/* child */
456 				ATF_CHECK_EQ(0, (fegetexcept() & ALL_STD_EXCEPT));
457 				ATF_REQUIRE_EQ(0, (feenableexcept(except) & ALL_STD_EXCEPT));
458 				ATF_CHECK_EQ(except, fegetexcept());
459 				raiseexcept(raise);
460 				ATF_CHECK_EQ(0, feraiseexcept(raise));
461 				ATF_CHECK_EQ(raise, fetestexcept(ALL_STD_EXCEPT));
462 
463 				ATF_CHECK_EQ(0, sigaction(SIGFPE, &act, NULL));
464 				switch (pass) {
465 				case 0:
466 					raiseexcept(except);
467 				case 1:
468 					feraiseexcept(except);
469 				default:
470 					ATF_REQUIRE(0);
471 				}
472 				ATF_REQUIRE(0);
473 			default:	/* parent */
474 				ATF_REQUIRE(wait(&status) > 0);
475 				/*
476 				 * Avoid assert() here so that it's possible
477 				 * to examine a failed child's core dump.
478 				 */
479 				if (!WIFEXITED(status))
480 					errx(1, "child aborted\n");
481 				ATF_CHECK_EQ(0, WEXITSTATUS(status));
482 				break;
483 			case -1:	/* error */
484 				ATF_REQUIRE(0);
485 			}
486 		}
487 	}
488 	ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
489 #endif
490 }
491 
492 /*
493  * Test feholdexcept() and feupdateenv().
494  *
495  * Prerequisites: fetestexcept(), fegetround(), fesetround(),
496  *	fedisableexcept(), feenableexcept()
497  */
498 ATF_TC_WITHOUT_HEAD(feholdupdate);
499 ATF_TC_BODY(feholdupdate, tc)
500 {
501 	fenv_t env;
502 
503 	struct sigaction act;
504 	int except, pass, status, raise;
505 	unsigned i;
506 
507 	sigemptyset(&act.sa_mask);
508 	act.sa_flags = 0;
509 	act.sa_handler = trap_handler;
510 	for (pass = 0; pass < 2; pass++) {
511 		for (i = 0; i < NEXCEPTS; i++) {
512 			except = std_excepts[i];
513 			/* over/underflow may also raise inexact */
514 			if (except == FE_INEXACT)
515 				raise = FE_DIVBYZERO | FE_INVALID;
516 			else
517 				raise = ALL_STD_EXCEPT ^ except;
518 
519 			/*
520 			 * We need to fork a child process because
521 			 * there isn't a portable way to recover from
522 			 * a floating-point exception.
523 			 */
524 			switch(fork()) {
525 			case 0:		/* child */
526 				/*
527 				 * We don't want to cause a fatal exception in
528 				 * the child until the second pass, so we can
529 				 * check other properties of feupdateenv().
530 				 */
531 				if (pass == 1)
532 					ATF_REQUIRE_EQ(0,
533 					    feenableexcept(except) &
534 					    ALL_STD_EXCEPT);
535 				raiseexcept(raise);
536 				ATF_CHECK_EQ(0, fesetround(FE_DOWNWARD));
537 				ATF_CHECK_EQ(0, feholdexcept(&env));
538 				ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
539 				raiseexcept(except);
540 				ATF_CHECK_EQ(0, fesetround(FE_UPWARD));
541 
542 				if (pass == 1)
543 					ATF_CHECK_EQ(0, sigaction(SIGFPE, &act, NULL));
544 				ATF_CHECK_EQ(0, feupdateenv(&env));
545 				ATF_CHECK_EQ(FE_DOWNWARD, fegetround());
546 				ATF_CHECK_EQ((except | raise), fetestexcept(ALL_STD_EXCEPT));
547 
548 				ATF_CHECK_EQ(0, pass);
549 				_exit(0);
550 			default:	/* parent */
551 				ATF_REQUIRE(wait(&status) > 0);
552 				/*
553 				 * Avoid assert() here so that it's possible
554 				 * to examine a failed child's core dump.
555 				 */
556 				if (!WIFEXITED(status))
557 					errx(1, "child aborted\n");
558 				ATF_CHECK_EQ(0, WEXITSTATUS(status));
559 				break;
560 			case -1:	/* error */
561 				ATF_REQUIRE(0);
562 			}
563 		}
564 #if defined(__arm__) || defined(__aarch64__) || defined(__riscv)
565 		break;
566 #endif
567 	}
568 	ATF_CHECK_EQ(0, fetestexcept(FE_ALL_EXCEPT));
569 }
570 
571 ATF_TP_ADD_TCS(tp)
572 {
573 	ATF_TP_ADD_TC(tp, dfl_env);
574 	ATF_TP_ADD_TC(tp, fetestclearexcept);
575 	ATF_TP_ADD_TC(tp, fegsetexceptflag);
576 	ATF_TP_ADD_TC(tp, feraiseexcept);
577 	ATF_TP_ADD_TC(tp, fegsetround);
578 	ATF_TP_ADD_TC(tp, fegsetenv);
579 	ATF_TP_ADD_TC(tp, masking);
580 	ATF_TP_ADD_TC(tp, feholdupdate);
581 
582 	return (atf_no_error());
583 }
584