1/* Test file for mpfr_set_ld and mpfr_get_ld. 2 3Copyright 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. 4Contributed by the Arenaire and Cacao projects, INRIA. 5 6This file is part of the GNU MPFR Library. 7 8The GNU MPFR Library is free software; you can redistribute it and/or modify 9it under the terms of the GNU Lesser General Public License as published by 10the Free Software Foundation; either version 3 of the License, or (at your 11option) any later version. 12 13The GNU MPFR Library is distributed in the hope that it will be useful, but 14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16License for more details. 17 18You should have received a copy of the GNU Lesser General Public License 19along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 2151 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23#include <stdio.h> 24#include <stdlib.h> 25#include <float.h> 26#include <limits.h> 27#ifdef WITH_FPU_CONTROL 28#include <fpu_control.h> 29#endif 30 31#include "mpfr-test.h" 32 33static void 34check_gcc33_bug (void) 35{ 36 volatile long double x; 37 x = (long double) 9007199254740992.0 + 1.0; 38 if (x != 0.0) 39 return; /* OK */ 40 printf 41 ("Detected optimization bug of gcc 3.3 on Alpha concerning long double\n" 42 "comparisons; set_ld tests might fail (set_ld won't work correctly).\n" 43 "See http://gcc.gnu.org/ml/gcc-bugs/2003-10/msg00853.html for more\n" 44 "information.\n"); 45} 46 47static int 48Isnan_ld (long double d) 49{ 50 double e = (double) d; 51 if (DOUBLE_ISNAN (e)) 52 return 1; 53 LONGDOUBLE_NAN_ACTION (d, goto yes); 54 return 0; 55 yes: 56 return 1; 57} 58 59/* checks that a long double converted to a mpfr (with precision >=113), 60 then converted back to a long double gives the initial value, 61 or in other words mpfr_get_ld(mpfr_set_ld(d)) = d. 62*/ 63static void 64check_set_get (long double d, mpfr_t x) 65{ 66 int r; 67 long double e; 68 int inex; 69 70 for (r = 0; r < MPFR_RND_MAX; r++) 71 { 72 inex = mpfr_set_ld (x, d, (mpfr_rnd_t) r); 73 if (inex != 0) 74 { 75 printf ("Error: mpfr_set_ld should be exact\n"); 76 printf ("d=%1.30Le inex=%d\n", d, inex); 77 printf ("emin=%ld emax=%ld\n", mpfr_get_emin (), mpfr_get_emax ()); 78 mpfr_dump (x); 79 exit (1); 80 } 81 e = mpfr_get_ld (x, (mpfr_rnd_t) r); 82 if ((Isnan_ld(d) && ! Isnan_ld(e)) || 83 (Isnan_ld(e) && ! Isnan_ld(d)) || 84 (e != d && !(Isnan_ld(e) && Isnan_ld(d)))) 85 { 86 printf ("Error: mpfr_get_ld o mpfr_set_ld <> Id\n"); 87 printf (" r=%d\n", r); 88 printf (" d=%1.30Le get_ld(set_ld(d))=%1.30Le\n", d, e); 89 ld_trace (" d", d); 90 printf (" x="); mpfr_out_str (NULL, 16, 0, x, MPFR_RNDN); 91 printf ("\n"); 92 ld_trace (" e", e); 93#ifdef MPFR_NANISNAN 94 if (Isnan_ld(d) || Isnan_ld(e)) 95 printf ("The reason is that NAN == NAN. Please look at the " 96 "configure output\nand Section \"In case of problem\" " 97 "of the INSTALL file.\n"); 98#endif 99 exit (1); 100 } 101 } 102} 103 104static void 105test_small (void) 106{ 107 mpfr_t x, y, z; 108 long double d; 109 110 mpfr_init2 (x, 64); 111 mpfr_init2 (y, 64); 112 mpfr_init2 (z, 64); 113 114 /* x = 11906603631607553907/2^(16381+64) */ 115 mpfr_set_str (x, "0.1010010100111100110000001110101101000111010110000001111101110011E-16381", 2, MPFR_RNDN); 116 d = mpfr_get_ld (x, MPFR_RNDN); /* infinite loop? */ 117 mpfr_set_ld (y, d, MPFR_RNDN); 118 mpfr_sub (z, x, y, MPFR_RNDN); 119 mpfr_abs (z, z, MPFR_RNDN); 120 mpfr_clear_erangeflag (); 121 /* If long double = double, d should be equal to 0; 122 in this case, everything is OK. */ 123 if (d != 0 && (mpfr_cmp_str (z, "1E-16434", 2, MPFR_RNDN) > 0 || 124 mpfr_erangeflag_p ())) 125 { 126 printf ("Error with x = "); 127 mpfr_out_str (NULL, 10, 21, x, MPFR_RNDN); 128 printf (" = "); 129 mpfr_out_str (NULL, 16, 0, x, MPFR_RNDN); 130 printf ("\n -> d = %.21Lg", d); 131 printf ("\n -> y = "); 132 mpfr_out_str (NULL, 10, 21, y, MPFR_RNDN); 133 printf (" = "); 134 mpfr_out_str (NULL, 16, 0, y, MPFR_RNDN); 135 printf ("\n -> |x-y| = "); 136 mpfr_out_str (NULL, 16, 0, z, MPFR_RNDN); 137 printf ("\n"); 138 exit (1); 139 } 140 141 mpfr_clear (x); 142 mpfr_clear (y); 143 mpfr_clear (z); 144} 145 146static void 147test_fixed_bugs (void) 148{ 149 mpfr_t x; 150 long double l, m; 151 152 /* bug found by Steve Kargl (2009-03-14) */ 153 mpfr_init2 (x, 64); 154 mpfr_set_ui_2exp (x, 1, -16447, MPFR_RNDN); 155 mpfr_get_ld (x, MPFR_RNDN); /* an assertion failed in init2.c:50 */ 156 157 /* bug reported by Jakub Jelinek (2010-10-17) 158 https://gforge.inria.fr/tracker/?func=detail&aid=11300 */ 159 mpfr_set_prec (x, MPFR_LDBL_MANT_DIG); 160 /* l = 0x1.23456789abcdef0123456789abcdp-914L; */ 161 l = 8.215640181713713164092636634579e-276; 162 mpfr_set_ld (x, l, MPFR_RNDN); 163 m = mpfr_get_ld (x, MPFR_RNDN); 164 if (m != l) 165 { 166 printf ("Error in get_ld o set_ld for l=%Le\n", l); 167 printf ("Got m=%Le instead of l\n", m); 168 exit (1); 169 } 170 171 /* another similar test which failed with extended double precision and the 172 generic code for mpfr_set_ld */ 173 /* l = 0x1.23456789abcdef0123456789abcdp-968L; */ 174 l = 4.560596445887084662336528403703e-292; 175 mpfr_set_ld (x, l, MPFR_RNDN); 176 m = mpfr_get_ld (x, MPFR_RNDN); 177 if (m != l) 178 { 179 printf ("Error in get_ld o set_ld for l=%Le\n", l); 180 printf ("Got m=%Le instead of l\n", m); 181 exit (1); 182 } 183 184 mpfr_clear (x); 185} 186 187int 188main (int argc, char *argv[]) 189{ 190 long double d, e; 191 mpfr_t x; 192 int i; 193 mpfr_exp_t emax; 194#ifdef WITH_FPU_CONTROL 195 fpu_control_t cw; 196 197 if (argc > 1) 198 { 199 cw = strtol(argv[1], NULL, 0); 200 printf ("FPU control word: 0x%x\n", (unsigned int) cw); 201 _FPU_SETCW (cw); 202 } 203#endif 204 205 check_gcc33_bug (); 206 test_fixed_bugs (); 207 208 tests_start_mpfr (); 209 mpfr_test_init (); 210 211 mpfr_init2 (x, MPFR_LDBL_MANT_DIG); 212 213 /* check NaN */ 214 mpfr_set_nan (x); 215 d = mpfr_get_ld (x, MPFR_RNDN); 216 check_set_get (d, x); 217 218 /* check +0.0 and -0.0 */ 219 d = 0.0; 220 check_set_get (d, x); 221 d = DBL_NEG_ZERO; 222 check_set_get (d, x); 223 224 /* check that the sign of -0.0 is set */ 225 mpfr_set_ld (x, DBL_NEG_ZERO, MPFR_RNDN); 226 if (MPFR_SIGN(x) > 0) 227 { 228 printf ("Error: sign of -0.0 is not set correctly\n"); 229#ifdef _GMP_IEEE_FLOATS 230 exit (1); 231 /* Non IEEE doesn't support negative zero yet */ 232#endif 233 } 234 235 /* check +Inf */ 236 mpfr_set_inf (x, 1); 237 d = mpfr_get_ld (x, MPFR_RNDN); 238 check_set_get (d, x); 239 240 /* check -Inf */ 241 mpfr_set_inf (x, -1); 242 d = mpfr_get_ld (x, MPFR_RNDN); 243 check_set_get (d, x); 244 245 /* check the largest power of two */ 246 d = 1.0; while (d < LDBL_MAX / 2.0) d += d; 247 check_set_get (d, x); 248 check_set_get (-d, x); 249 250 /* check largest long double */ 251 d = LDBL_MAX; 252 check_set_get (d, x); 253 check_set_get (-d, x); 254 255 /* check the smallest power of two */ 256 d = 1.0; 257 while ((e = d / 2.0) != (long double) 0.0 && e != d) 258 d = e; 259 check_set_get (d, x); 260 check_set_get (-d, x); 261 262 /* check largest 2^(2^k) that is representable as a long double */ 263 d = (LDBL_MAX / 2) + (LDBL_MAX / 4 * LDBL_EPSILON); 264 check_set_get (d, x); 265 266 /* check that 2^i, 2^i+1 and 2^i-1 are correctly converted */ 267 d = 1.0; 268 for (i = 1; i < MPFR_LDBL_MANT_DIG; i++) 269 { 270 d = 2.0 * d; /* d = 2^i */ 271 check_set_get (d, x); 272 check_set_get (d + 1.0, x); 273 check_set_get (d - 1.0, x); 274 } 275 276 for (i = 0; i < 10000; i++) 277 { 278 mpfr_urandomb (x, RANDS); 279 d = mpfr_get_ld (x, MPFR_RNDN); 280 check_set_get (d, x); 281 } 282 283 /* check with reduced emax to exercise overflow */ 284 emax = mpfr_get_emax (); 285 mpfr_set_prec (x, 2); 286 set_emax (1); 287 mpfr_set_ld (x, (long double) 2.0, MPFR_RNDN); 288 MPFR_ASSERTN(mpfr_inf_p (x) && mpfr_sgn (x) > 0); 289 for (d = (long double) 2.0, i = 0; i < 13; i++, d *= d); 290 /* now d = 2^8192 */ 291 mpfr_set_ld (x, d, MPFR_RNDN); 292 MPFR_ASSERTN(mpfr_inf_p (x) && mpfr_sgn (x) > 0); 293 set_emax (emax); 294 295 mpfr_clear (x); 296 297 test_small (); 298 299 tests_end_mpfr (); 300 301 return 0; 302} 303