1 /* Test file for mpfr_ui_sub. 2 3 Copyright 2000-2016 Free Software Foundation, Inc. 4 Contributed by the AriC and Caramba projects, INRIA. 5 6 This file is part of the GNU MPFR Library. 7 8 The GNU MPFR Library is free software; you can redistribute it and/or modify 9 it under the terms of the GNU Lesser General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or (at your 11 option) any later version. 12 13 The GNU MPFR Library is distributed in the hope that it will be useful, but 14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16 License for more details. 17 18 You should have received a copy of the GNU Lesser General Public License 19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20 http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23 #include <stdio.h> 24 #include <stdlib.h> 25 #include <float.h> 26 27 #include "mpfr-test.h" 28 29 static void 30 special (void) 31 { 32 mpfr_t x, y, res; 33 int inexact; 34 35 mpfr_init (x); 36 mpfr_init (y); 37 mpfr_init (res); 38 39 mpfr_set_prec (x, 24); 40 mpfr_set_prec (y, 24); 41 mpfr_set_str_binary (y, "0.111100110001011010111"); 42 inexact = mpfr_ui_sub (x, 1, y, MPFR_RNDN); 43 if (inexact) 44 { 45 printf ("Wrong inexact flag: got %d, expected 0\n", inexact); 46 exit (1); 47 } 48 49 mpfr_set_prec (x, 24); 50 mpfr_set_prec (y, 24); 51 mpfr_set_str_binary (y, "0.111100110001011010111"); 52 if ((inexact = mpfr_ui_sub (x, 38181761, y, MPFR_RNDN)) >= 0) 53 { 54 printf ("Wrong inexact flag: got %d, expected -1\n", inexact); 55 exit (1); 56 } 57 58 mpfr_set_prec (x, 63); 59 mpfr_set_prec (y, 63); 60 mpfr_set_str_binary (y, "0.111110010010100100110101101010001001100101110001000101110111111E-1"); 61 if ((inexact = mpfr_ui_sub (x, 1541116494, y, MPFR_RNDN)) <= 0) 62 { 63 printf ("Wrong inexact flag: got %d, expected +1\n", inexact); 64 exit (1); 65 } 66 67 mpfr_set_prec (x, 32); 68 mpfr_set_prec (y, 32); 69 mpfr_set_str_binary (y, "0.11011000110111010001011100011100E-1"); 70 if ((inexact = mpfr_ui_sub (x, 2000375416, y, MPFR_RNDN)) >= 0) 71 { 72 printf ("Wrong inexact flag: got %d, expected -1\n", inexact); 73 exit (1); 74 } 75 76 mpfr_set_prec (x, 24); 77 mpfr_set_prec (y, 24); 78 mpfr_set_str_binary (y, "0.110011011001010011110111E-2"); 79 if ((inexact = mpfr_ui_sub (x, 927694848, y, MPFR_RNDN)) <= 0) 80 { 81 printf ("Wrong inexact flag: got %d, expected +1\n", inexact); 82 exit (1); 83 } 84 85 /* bug found by Mathieu Dutour, 12 Apr 2001 */ 86 mpfr_set_prec (x, 5); 87 mpfr_set_prec (y, 5); 88 mpfr_set_prec (res, 5); 89 mpfr_set_str_binary (x, "1e-12"); 90 91 mpfr_ui_sub (y, 1, x, MPFR_RNDD); 92 mpfr_set_str_binary (res, "0.11111"); 93 if (mpfr_cmp (y, res)) 94 { 95 printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDD) for x=2^(-12)\nexpected 1.1111e-1, got "); 96 mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN); 97 printf ("\n"); 98 exit (1); 99 } 100 101 mpfr_ui_sub (y, 1, x, MPFR_RNDU); 102 mpfr_set_str_binary (res, "1.0"); 103 if (mpfr_cmp (y, res)) 104 { 105 printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDU) for x=2^(-12)\n" 106 "expected 1.0, got "); 107 mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN); 108 printf ("\n"); 109 exit (1); 110 } 111 112 mpfr_ui_sub (y, 1, x, MPFR_RNDN); 113 mpfr_set_str_binary (res, "1.0"); 114 if (mpfr_cmp (y, res)) 115 { 116 printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDN) for x=2^(-12)\n" 117 "expected 1.0, got "); 118 mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN); 119 printf ("\n"); 120 exit (1); 121 } 122 123 mpfr_set_prec (x, 10); 124 mpfr_set_prec (y, 10); 125 mpfr_urandomb (x, RANDS); 126 mpfr_ui_sub (y, 0, x, MPFR_RNDN); 127 if (MPFR_IS_ZERO(x)) 128 MPFR_ASSERTN(MPFR_IS_ZERO(y)); 129 else 130 MPFR_ASSERTN(mpfr_cmpabs (x, y) == 0 && mpfr_sgn (x) != mpfr_sgn (y)); 131 132 mpfr_set_prec (x, 73); 133 mpfr_set_str_binary (x, "0.1101111010101011011011100011010000000101110001011111001011011000101111101E-99"); 134 mpfr_ui_sub (x, 1, x, MPFR_RNDZ); 135 mpfr_nextabove (x); 136 MPFR_ASSERTN(mpfr_cmp_ui (x, 1) == 0); 137 138 mpfr_clear (x); 139 mpfr_clear (y); 140 mpfr_clear (res); 141 } 142 143 /* checks that (y-x) gives the right results with 53 bits of precision */ 144 static void 145 check (unsigned long y, const char *xs, mpfr_rnd_t rnd_mode, const char *zs) 146 { 147 mpfr_t xx, zz; 148 149 mpfr_inits2 (53, xx, zz, (mpfr_ptr) 0); 150 mpfr_set_str1 (xx, xs); 151 mpfr_ui_sub (zz, y, xx, rnd_mode); 152 if (mpfr_cmp_str1 (zz, zs) ) 153 { 154 printf ("expected difference is %s, got\n",zs); 155 mpfr_out_str(stdout, 10, 0, zz, MPFR_RNDN); 156 printf ("mpfr_ui_sub failed for y=%lu x=%s with rnd_mode=%s\n", 157 y, xs, mpfr_print_rnd_mode (rnd_mode)); 158 exit (1); 159 } 160 mpfr_clears (xx, zz, (mpfr_ptr) 0); 161 } 162 163 /* if u = o(x-y), v = o(u-x), w = o(v+y), then x-y = u-w */ 164 static void 165 check_two_sum (mpfr_prec_t p) 166 { 167 unsigned int x; 168 mpfr_t y, u, v, w; 169 mpfr_rnd_t rnd; 170 int inexact, cmp; 171 172 mpfr_inits2 (p, y, u, v, w, (mpfr_ptr) 0); 173 do 174 { 175 x = randlimb (); 176 } 177 while (x < 1); 178 mpfr_urandomb (y, RANDS); 179 rnd = MPFR_RNDN; 180 inexact = mpfr_ui_sub (u, x, y, rnd); 181 mpfr_sub_ui (v, u, x, rnd); 182 mpfr_add (w, v, y, rnd); 183 cmp = mpfr_cmp_ui (w, 0); 184 /* as u = (x-y) + w, we should have inexact and w of same sign */ 185 if (! SAME_SIGN (inexact, cmp)) 186 { 187 printf ("Wrong inexact flag for prec=%u, rnd=%s\n", 188 (unsigned int) p, mpfr_print_rnd_mode (rnd)); 189 printf ("x = %u\n", x); 190 printf ("y = "); mpfr_dump (y); 191 printf ("u = "); mpfr_dump (u); 192 printf ("v = "); mpfr_dump (v); 193 printf ("w = "); mpfr_dump (w); 194 printf ("inexact = %d\n", inexact); 195 exit (1); 196 } 197 mpfr_clears (y, u, v, w, (mpfr_ptr) 0); 198 } 199 200 static void 201 check_nans (void) 202 { 203 mpfr_t x, y; 204 205 mpfr_init2 (x, 123L); 206 mpfr_init2 (y, 123L); 207 208 /* 1 - nan == nan */ 209 mpfr_set_nan (x); 210 mpfr_ui_sub (y, 1L, x, MPFR_RNDN); 211 MPFR_ASSERTN (mpfr_nan_p (y)); 212 213 /* 1 - +inf == -inf */ 214 mpfr_set_inf (x, 1); 215 mpfr_ui_sub (y, 1L, x, MPFR_RNDN); 216 MPFR_ASSERTN (mpfr_inf_p (y)); 217 MPFR_ASSERTN (mpfr_sgn (y) < 0); 218 219 /* 1 - -inf == +inf */ 220 mpfr_set_inf (x, -1); 221 mpfr_ui_sub (y, 1L, x, MPFR_RNDN); 222 MPFR_ASSERTN (mpfr_inf_p (y)); 223 MPFR_ASSERTN (mpfr_sgn (y) > 0); 224 225 mpfr_clear (x); 226 mpfr_clear (y); 227 } 228 229 /* Check mpfr_ui_sub with u = 0 (unsigned). */ 230 static void check_neg (void) 231 { 232 mpfr_t x, yneg, ysub; 233 int i, s; 234 int r; 235 236 mpfr_init2 (x, 64); 237 mpfr_init2 (yneg, 32); 238 mpfr_init2 (ysub, 32); 239 240 for (i = 0; i <= 25; i++) 241 { 242 mpfr_sqrt_ui (x, i, MPFR_RNDN); 243 for (s = 0; s <= 1; s++) 244 { 245 RND_LOOP (r) 246 { 247 int tneg, tsub; 248 249 tneg = mpfr_neg (yneg, x, (mpfr_rnd_t) r); 250 tsub = mpfr_ui_sub (ysub, 0, x, (mpfr_rnd_t) r); 251 MPFR_ASSERTN (mpfr_equal_p (yneg, ysub)); 252 MPFR_ASSERTN (!(MPFR_IS_POS (yneg) ^ MPFR_IS_POS (ysub))); 253 MPFR_ASSERTN (tneg == tsub); 254 } 255 mpfr_neg (x, x, MPFR_RNDN); 256 } 257 } 258 259 mpfr_clear (x); 260 mpfr_clear (yneg); 261 mpfr_clear (ysub); 262 } 263 264 static void 265 check_overflow (void) 266 { 267 mpfr_exp_t emin, emax; 268 mpfr_t x, y1, y2; 269 int inex1, inex2, rnd_mode; 270 unsigned int flags1, flags2; 271 272 emin = mpfr_get_emin (); 273 emax = mpfr_get_emax (); 274 set_emin (MPFR_EMIN_MIN); 275 set_emax (MPFR_EMAX_MAX); 276 277 mpfr_inits2 (32, x, y1, y2, (mpfr_ptr) 0); 278 mpfr_setmax (x, MPFR_EMAX_MAX); 279 mpfr_neg (x, x, MPFR_RNDN); 280 RND_LOOP (rnd_mode) 281 { 282 if (rnd_mode == MPFR_RNDU || rnd_mode == MPFR_RNDA) 283 { 284 inex1 = mpfr_overflow (y1, (mpfr_rnd_t) rnd_mode, 1); 285 flags1 = MPFR_FLAGS_OVERFLOW | MPFR_FLAGS_INEXACT; 286 } 287 else 288 { 289 mpfr_neg (y1, x, MPFR_RNDN); 290 inex1 = -1; 291 flags1 = MPFR_FLAGS_INEXACT; 292 } 293 mpfr_clear_flags (); 294 inex2 = mpfr_ui_sub (y2, 1, x, (mpfr_rnd_t) rnd_mode); 295 flags2 = __gmpfr_flags; 296 if (!(mpfr_equal_p (y1, y2) && 297 SAME_SIGN (inex1, inex2) && 298 flags1 == flags2)) 299 { 300 printf ("Error in check_overflow for %s\n", 301 mpfr_print_rnd_mode ((mpfr_rnd_t) rnd_mode)); 302 printf ("Expected "); 303 mpfr_dump (y1); 304 printf (" with inex = %d, flags =", inex1); 305 flags_out (flags1); 306 printf ("Got "); 307 mpfr_dump (y2); 308 printf (" with inex = %d, flags =", inex2); 309 flags_out (flags2); 310 exit (1); 311 } 312 } 313 mpfr_clears (x, y1, y2, (mpfr_ptr) 0); 314 315 set_emin (emin); 316 set_emax (emax); 317 } 318 319 #define TEST_FUNCTION mpfr_ui_sub 320 #define ULONG_ARG1 321 #include "tgeneric.c" 322 323 int 324 main (int argc, char *argv[]) 325 { 326 mpfr_prec_t p; 327 unsigned k; 328 329 tests_start_mpfr (); 330 331 check_nans (); 332 333 special (); 334 for (p=2; p<100; p++) 335 for (k=0; k<100; k++) 336 check_two_sum (p); 337 338 check(1196426492, "1.4218093058435347e-3", MPFR_RNDN, 339 "1.1964264919985781e9"); 340 check(1092583421, "-1.0880649218158844e9", MPFR_RNDN, 341 "2.1806483428158845901e9"); 342 check(948002822, "1.22191250737771397120e+20", MPFR_RNDN, 343 "-1.2219125073682338611e20"); 344 check(832100416, "4.68311314939691330000e-215", MPFR_RNDD, 345 "8.3210041599999988079e8"); 346 check(1976245324, "1.25296395864546893357e+232", MPFR_RNDZ, 347 "-1.2529639586454686577e232"); 348 check(2128997392, "-1.08496826129284207724e+187", MPFR_RNDU, 349 "1.0849682612928422704e187"); 350 check(293607738, "-1.9967571564050541e-5", MPFR_RNDU, 351 "2.9360773800002003e8"); 352 check(354270183, "2.9469161763489528e3", MPFR_RNDN, 353 "3.5426723608382362e8"); 354 check_overflow (); 355 356 check_neg (); 357 358 test_generic (2, 1000, 100); 359 360 tests_end_mpfr (); 361 return 0; 362 } 363