1 /* Test for correct rounding of results of strtod and related
2    functions.
3    Copyright (C) 2012-2022 Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5 
6    The GNU C Library is free software; you can redistribute it and/or
7    modify it under the terms of the GNU Lesser General Public
8    License as published by the Free Software Foundation; either
9    version 2.1 of the License, or (at your option) any later version.
10 
11    The GNU C Library is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14    Lesser General Public License for more details.
15 
16    You should have received a copy of the GNU Lesser General Public
17    License along with the GNU C Library; if not, see
18    <https://www.gnu.org/licenses/>.  */
19 
20 /* Defining _LIBC_TEST ensures long double math functions are
21    declared in the headers.  */
22 #define _LIBC_TEST 1
23 #define __STDC_WANT_IEC_60559_TYPES_EXT__
24 #include <fenv.h>
25 #include <float.h>
26 #include <math.h>
27 #include <stdbool.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <math-tests.h>
32 
33 #include "tst-strtod.h"
34 
35 /* Non-standard macros expected to be externally defined:
36 
37    L_(str): Pastes the appropriate modifier to a string literal str.
38 
39    FNPFX: Expands to the correct prefix for the strtod equivalent
40           of type CHAR. (e.g str or wcs).
41 
42    CHAR: Expands to the string type being tested (e.g wchar_t or char).
43 
44    STRM: Expands to a string literal suitable for printing CHAR* via
45          printf (e.g "%s" or "%ls"). */
46 
47 #define _CONCAT(a, b) a ## b
48 #define CONCAT(a, b) _CONCAT (a, b)
49 
50 #define STRTO(x) CONCAT (CONCAT (FNPFX, to), x)
51 
52 #if LDBL_MANT_DIG == 106 && LDBL_MAX_EXP == 1024
53 /* This is a stupid hack for IBM long double.  This test ignores
54    inexact values for long double due to the limitations of the
55    format.  This ensures rounding tests are ignored.  */
56 # undef ROUNDING_TESTS_long_double
57 # define ROUNDING_TESTS_long_double(x) 0
58 #endif
59 
60 /* Generator to create an FTYPE member variabled named FSUF
61    used to populate struct member variables.  */
62 #define FTYPE_MEMBER(FSUF, FTYPE, FTOSTR, LSUF, CSUF)  \
63        FTYPE FSUF;
64 
65 /* Likewise, but each member is of type bool.  */
66 #define BOOL_MEMBER(FSUF, FTYPE, FTOSTR, LSUF, CSUF)  \
67        bool FSUF;
68 
69 #define STRUCT_FOREACH_FLOAT_FTYPE GEN_TEST_STRTOD_FOREACH (FTYPE_MEMBER)
70 #define STRUCT_FOREACH_FLOAT_BOOL GEN_TEST_STRTOD_FOREACH (BOOL_MEMBER)
71 
72 /* Define the long double choose (CHOOSE_ld) macro
73    to select the appropriate generated long double
74    value from the generated test data.  */
75 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
76 /* This is for the long double == double format.  */
77 # define CHOOSE_ld(f,d,...) d
78 #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 && LDBL_MIN_EXP == -16381
79 /* This is for the Intel extended float format.  */
80 # define CHOOSE_ld(f,d,ld64i,...) ld64i
81 #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 && LDBL_MIN_EXP == -16382
82 /* This is for the Motorola extended float format.  */
83 # define CHOOSE_ld(f,d,ld64i,ld64m,...) ld64m
84 #elif LDBL_MANT_DIG == 106 && LDBL_MAX_EXP == 1024
85 /* This is for the IBM extended double format.  */
86 # define CHOOSE_ld(f,d,ld64i,ld64m,ld106,...) ld106
87 #elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
88 /* This is for the IEEE binary128 format.  */
89 # define CHOOSE_ld(f,d,ld64i,ld64m,ld106,ld113,...) ld113
90 #else
91 # error "unknown long double format"
92 #endif
93 
94 /* Add type specific choosing macros below.  */
95 #define CHOOSE_f(f,...) f
96 #define CHOOSE_f32(f,...) f
97 #define CHOOSE_d(f,d,...) d
98 #define CHOOSE_f64(f,d,...) d
99 #define CHOOSE_f32x(f,d,...) d
100 #define CHOOSE_f128(f,d,ld64i,ld64m,ld106,ld113,...) ld113
101 /* long double is special, and handled above.  _Float16 would require
102    updates to the generator to generate appropriate expectations, and
103    updates to the test inputs to cover difficult rounding cases for
104    _Float16.  */
105 
106 #if __HAVE_FLOAT64X
107 # if FLT64X_MANT_DIG == 113 && FLT64X_MAX_EXP == 16384
108 #  define CHOOSE_f64x(f,d,ld64i,ld64m,ld106,ld113,...) ld113
109 # elif (FLT64X_MANT_DIG == 64			\
110 	&& FLT64X_MAX_EXP == 16384		\
111 	&& FLT64X_MIN_EXP == -16381)
112 #  define CHOOSE_f64x(f,d,ld64i,...) ld64i
113 # else
114 #  error "unknown _Float64x format"
115 # endif
116 #endif
117 
118 /* Selector for expected result field of a given type.  */
119 #define _ENTRY(FSUF, FTYPE, FTOSTR, LSUF, CSUF, ...)  \
120   CONCAT (CHOOSE_ ## FSUF (__VA_ARGS__), LSUF),
121 #define ENTRY(...) \
122   GEN_TEST_STRTOD_FOREACH (_ENTRY, __VA_ARGS__)
123 
124 /* Selector for boolean exact tag of expected results and that for
125    overflow.  */
126 #define _XNTRY(FSUF, FTYPE, FTOSTR, LSUF, CSUF, ...)  \
127   CHOOSE_ ## FSUF (__VA_ARGS__),
128 #define XNTRY(...) \
129   GEN_TEST_STRTOD_FOREACH (_XNTRY, __VA_ARGS__)
130 
131 /* This is hacky way around the seemingly unavoidable macro
132    expansion of the INFINITY or HUGE_VAL like macros in the
133    above.  It is assumed the compiler will implicitly convert
134    the infinity correctly.  */
135 #define INF INFINITY + 0.0
136 
137 /* This macro is used in conjunction with the output from the
138    gen-tst-strtod-round utility to select the appropriately
139    rounded long double value for a given format.  */
140 #define TEST(s,							\
141 	     fx, fd, fdo, fn, fno, fz, fzo, fu, fuo,		\
142 	     dx, dd, ddo, dn, dno, dz, dzo, du, duo,		\
143 	     ld64ix, ld64id, ld64ido, ld64in, ld64ino,		\
144 	     ld64iz, ld64izo, ld64iu, ld64iuo,			\
145 	     ld64mx, ld64md, ld64mdo, ld64mn, ld64mno,		\
146 	     ld64mz, ld64mzo, ld64mu, ld64muo,			\
147 	     ld106x, ld106d, ld106do, ld106n, ld106no,		\
148 	     ld106z, ld106zo, ld106u, ld106uo,			\
149 	     ld113x, ld113d, ld113do, ld113n, ld113no,		\
150 	     ld113z, ld113zo, ld113u, ld113uo)			\
151   {								\
152     L_ (s),							\
153     { XNTRY (fx, dx, ld64ix, ld64mx, ld106x, ld113x) },		\
154     {								\
155     { ENTRY (fn, dn, ld64in, ld64mn, ld106n, ld113n) },		\
156     { ENTRY (fd, dd, ld64id, ld64md, ld106d, ld113d) },		\
157     { ENTRY (fz, dz, ld64iz, ld64mz, ld106z, ld113z) },		\
158     { ENTRY (fu, du, ld64iu, ld64mu, ld106u, ld113u) }		\
159     },								\
160     {								\
161     { XNTRY (fno, dno, ld64ino, ld64mno, ld106no, ld113no) },	\
162     { XNTRY (fdo, ddo, ld64ido, ld64mdo, ld106do, ld113do) },	\
163     { XNTRY (fzo, dzo, ld64izo, ld64mzo, ld106zo, ld113zo) },	\
164     { XNTRY (fuo, duo, ld64iuo, ld64muo, ld106uo, ld113uo) }	\
165     }								\
166   }
167 
168 struct test_exactness
169   {
170   STRUCT_FOREACH_FLOAT_BOOL
171   };
172 
173 struct test_results
174   {
175   STRUCT_FOREACH_FLOAT_FTYPE
176   };
177 
178 struct test_overflow
179   {
180   STRUCT_FOREACH_FLOAT_BOOL
181   };
182 
183 struct test {
184   const CHAR *s;
185   struct test_exactness exact;
186   struct test_results r[4];
187   struct test_overflow o[4];
188 };
189 
190 /* Include the generated test data.  */
191 #include "tst-strtod-round-data.h"
192 
193 #define STRX(x) #x
194 #define STR(x) STRX (x)
195 #define FNPFXS STR (FNPFX)
196 
197 #ifndef FE_INEXACT
198 # define FE_INEXACT 0
199 #endif
200 
201 #ifndef FE_OVERFLOW
202 # define FE_OVERFLOW 0
203 #endif
204 
205 #define GEN_ONE_TEST(FSUF, FTYPE, FTOSTR, LSUF, CSUF)		\
206 {								\
207   feclearexcept (FE_ALL_EXCEPT);				\
208   FTYPE f = STRTO (FSUF) (s, NULL);				\
209   if (f != expected->FSUF					\
210       || (copysign ## CSUF) (1.0 ## LSUF, f)			\
211 	 != (copysign ## CSUF) (1.0 ## LSUF, expected->FSUF))	\
212     {								\
213       char efstr[FSTRLENMAX];					\
214       char fstr[FSTRLENMAX];					\
215       FTOSTR (efstr, FSTRLENMAX, "%a", expected->FSUF);		\
216       FTOSTR (fstr, FSTRLENMAX, "%a", f);			\
217       printf (FNPFXS "to" #FSUF  " (" STRM ") returned %s not "	\
218 	      "%s (%s)\n", s, fstr, efstr, mode_name);		\
219       if (ROUNDING_TESTS (FTYPE, rnd_mode) || exact->FSUF)	\
220 	result = 1;						\
221       else							\
222 	printf ("ignoring this inexact result\n");		\
223     }								\
224   else								\
225     {								\
226       if (FE_INEXACT != 0)					\
227 	{							\
228 	  bool inexact_raised = fetestexcept (FE_INEXACT) != 0;	\
229 	  if (inexact_raised != !exact->FSUF)			\
230 	    {							\
231 	      printf (FNPFXS "to" #FSUF				\
232 		      " (" STRM ") inexact %d "			\
233 		      "not %d\n", s, inexact_raised,		\
234 		      !exact->FSUF);				\
235 	      if (EXCEPTION_TESTS (FTYPE))			\
236 		result = 1;					\
237 	      else						\
238 		printf ("ignoring this exception error\n");	\
239 	    }							\
240 	}							\
241       if (FE_OVERFLOW != 0)					\
242 	{							\
243 	  bool overflow_raised					\
244 	    = fetestexcept (FE_OVERFLOW) != 0;			\
245 	  if (overflow_raised != overflow->FSUF)		\
246 	    {							\
247 	      printf (FNPFXS "to" #FSUF				\
248 		      " (" STRM ") overflow %d "		\
249 		      "not %d\n", s, overflow_raised,		\
250 		      overflow->FSUF);				\
251 	      if (EXCEPTION_TESTS (FTYPE))			\
252 		result = 1;					\
253 	      else						\
254 		printf ("ignoring this exception error\n");	\
255 	    }							\
256 	}							\
257     }								\
258 }
259 
260 static int
test_in_one_mode(const CHAR * s,const struct test_results * expected,const struct test_exactness * exact,const struct test_overflow * overflow,const char * mode_name,int rnd_mode)261 test_in_one_mode (const CHAR *s, const struct test_results *expected,
262 		    const struct test_exactness *exact,
263 		    const struct test_overflow *overflow,
264 		    const char *mode_name, int rnd_mode)
265 {
266   int result = 0;
267   GEN_TEST_STRTOD_FOREACH (GEN_ONE_TEST)
268   return result;
269 }
270 
271 static const struct fetestmodes
272   {
273   const char *mode_name;
274   int rnd_mode;
275   int rnd_i; /* Corresponding index into r array of struct test.  */
276   } modes[] = {
277     { "default rounding mode", FE_TONEAREST, 0 },
278 #ifdef FE_DOWNWARD
279     { "FE_DOWNWARD", FE_DOWNWARD, 1 },
280 #endif
281 #ifdef FE_TOWARDZERO
282     { "FE_TOWARDZERO", FE_TOWARDZERO, 2 },
283 #endif
284 #ifdef FE_UPWARD
285     { "FE_UPWARD", FE_UPWARD, 3 },
286 #endif
287     {}
288 };
289 
290 static int
do_test(void)291 do_test (void)
292 {
293   int save_round_mode __attribute__ ((unused)) = fegetround ();
294   int result = 0;
295   for (size_t i = 0; i < sizeof (tests) / sizeof (tests[0]); i++)
296     {
297       result |= test_in_one_mode (tests[i].s, &tests[i].r[modes[0].rnd_i],
298 				  &tests[i].exact, &tests[i].o[modes[0].rnd_i],
299 				  modes[0].mode_name, modes[0].rnd_mode);
300       for (const struct fetestmodes *m = &modes[1]; m->mode_name != NULL; m++)
301 	{
302 	  if (!fesetround (m->rnd_mode))
303 	    {
304 	      result |= test_in_one_mode (tests[i].s, &tests[i].r[m->rnd_i],
305 					  &tests[i].exact,
306 					  &tests[i].o[m->rnd_i], m->mode_name,
307 					  m->rnd_mode);
308 	      fesetround (save_round_mode);
309 	    }
310 	}
311     }
312   return result;
313 }
314 
315 #define TEST_FUNCTION do_test ()
316 #include "../test-skeleton.c"
317