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Diffstat (limited to 'lib/msun/tests/logarithm_test.c')
| -rw-r--r-- | lib/msun/tests/logarithm_test.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/lib/msun/tests/logarithm_test.c b/lib/msun/tests/logarithm_test.c new file mode 100644 index 0000000..18b9ebe --- /dev/null +++ b/lib/msun/tests/logarithm_test.c @@ -0,0 +1,286 @@ +/*- + * Copyright (c) 2008-2010 David Schultz <das@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* + * Tests for corner cases in log*(). + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <assert.h> +#include <fenv.h> +#include <float.h> +#include <math.h> +#include <stdio.h> + +#ifdef __i386__ +#include <ieeefp.h> +#endif + +#include "test-utils.h" + +#pragma STDC FENV_ACCESS ON + +/* + * Test that a function returns the correct value and sets the + * exception flags correctly. The exceptmask specifies which + * exceptions we should check. We need to be lenient for several + * reasoons, but mainly because on some architectures it's impossible + * to raise FE_OVERFLOW without raising FE_INEXACT. + * + * These are macros instead of functions so that assert provides more + * meaningful error messages. + * + * XXX The volatile here is to avoid gcc's bogus constant folding and work + * around the lack of support for the FENV_ACCESS pragma. + */ +#define test(func, x, result, exceptmask, excepts) do { \ + volatile long double _d = x; \ + assert(feclearexcept(FE_ALL_EXCEPT) == 0); \ + assert(fpequal((func)(_d), (result))); \ + assert(((void)(func), fetestexcept(exceptmask) == (excepts))); \ +} while (0) + +#define test(func, x, result, exceptmask, excepts) do { \ + volatile long double _d = x; \ + assert(feclearexcept(FE_ALL_EXCEPT) == 0); \ + assert(fpequal((func)(_d), (result))); \ + assert(((void)(func), fetestexcept(exceptmask) == (excepts))); \ +} while (0) + +#define test_tol(func, z, result, tol) do { \ + volatile long double _d = z; \ + debug(" testing %6s(%15La) ~= % .36Le\n", #func, _d, result); \ + assert(fpequal_tol((func)(_d), (result), (tol), CS_BOTH)); \ +} while (0) + +/* Test all the functions that compute log(x). */ +#define testall0(x, result, exceptmask, excepts) do { \ + test(log, x, result, exceptmask, excepts); \ + test(logf, x, result, exceptmask, excepts); \ + test(logl, x, result, exceptmask, excepts); \ + test(log2, x, result, exceptmask, excepts); \ + test(log2f, x, result, exceptmask, excepts); \ + test(log2l, x, result, exceptmask, excepts); \ + test(log10, x, result, exceptmask, excepts); \ + test(log10f, x, result, exceptmask, excepts); \ + test(log10l, x, result, exceptmask, excepts); \ +} while (0) + +/* Test all the functions that compute log(1+x). */ +#define testall1(x, result, exceptmask, excepts) do { \ + test(log1p, x, result, exceptmask, excepts); \ + test(log1pf, x, result, exceptmask, excepts); \ + test(log1pl, x, result, exceptmask, excepts); \ +} while (0) + +void +run_generic_tests(void) +{ + + /* log(1) == 0, no exceptions raised */ + testall0(1.0, 0.0, ALL_STD_EXCEPT, 0); + testall1(0.0, 0.0, ALL_STD_EXCEPT, 0); + testall1(-0.0, -0.0, ALL_STD_EXCEPT, 0); + + /* log(NaN) == NaN, no exceptions raised */ + testall0(NAN, NAN, ALL_STD_EXCEPT, 0); + testall1(NAN, NAN, ALL_STD_EXCEPT, 0); + + /* log(Inf) == Inf, no exceptions raised */ + testall0(INFINITY, INFINITY, ALL_STD_EXCEPT, 0); + testall1(INFINITY, INFINITY, ALL_STD_EXCEPT, 0); + + /* log(x) == NaN for x < 0, invalid exception raised */ + testall0(-INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID); + testall1(-INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID); + testall0(-1.0, NAN, ALL_STD_EXCEPT, FE_INVALID); + testall1(-1.5, NAN, ALL_STD_EXCEPT, FE_INVALID); + + /* log(0) == -Inf, divide-by-zero exception */ + testall0(0.0, -INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_DIVBYZERO); + testall0(-0.0, -INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_DIVBYZERO); + testall1(-1.0, -INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_DIVBYZERO); +} + +void +run_log2_tests(void) +{ + int i; + + /* + * We should insist that log2() return exactly the correct + * result and not raise an inexact exception for powers of 2. + */ + feclearexcept(FE_ALL_EXCEPT); + for (i = FLT_MIN_EXP - FLT_MANT_DIG; i < FLT_MAX_EXP; i++) { + assert(log2f(ldexpf(1.0, i)) == i); + assert(fetestexcept(ALL_STD_EXCEPT) == 0); + } + for (i = DBL_MIN_EXP - DBL_MANT_DIG; i < DBL_MAX_EXP; i++) { + assert(log2(ldexp(1.0, i)) == i); + assert(fetestexcept(ALL_STD_EXCEPT) == 0); + } + for (i = LDBL_MIN_EXP - LDBL_MANT_DIG; i < LDBL_MAX_EXP; i++) { + assert(log2l(ldexpl(1.0, i)) == i); +#if 0 + /* XXX This test does not pass yet. */ + assert(fetestexcept(ALL_STD_EXCEPT) == 0); +#endif + } +} + +void +run_roundingmode_tests(void) +{ + + /* + * Corner cases in other rounding modes. + */ + fesetround(FE_DOWNWARD); + /* These are still positive per IEEE 754R */ +#if 0 + testall0(1.0, 0.0, ALL_STD_EXCEPT, 0); +#else + /* logl, log2l, and log10l don't pass yet. */ + test(log, 1.0, 0.0, ALL_STD_EXCEPT, 0); + test(logf, 1.0, 0.0, ALL_STD_EXCEPT, 0); + test(log2, 1.0, 0.0, ALL_STD_EXCEPT, 0); + test(log2f, 1.0, 0.0, ALL_STD_EXCEPT, 0); + test(log10, 1.0, 0.0, ALL_STD_EXCEPT, 0); + test(log10f, 1.0, 0.0, ALL_STD_EXCEPT, 0); +#endif + testall1(0.0, 0.0, ALL_STD_EXCEPT, 0); + fesetround(FE_TOWARDZERO); + testall0(1.0, 0.0, ALL_STD_EXCEPT, 0); + testall1(0.0, 0.0, ALL_STD_EXCEPT, 0); + + fesetround(FE_UPWARD); + testall0(1.0, 0.0, ALL_STD_EXCEPT, 0); + testall1(0.0, 0.0, ALL_STD_EXCEPT, 0); + /* log1p(-0.0) == -0.0 even when rounding upwards */ + testall1(-0.0, -0.0, ALL_STD_EXCEPT, 0); + + fesetround(FE_TONEAREST); +} + +void +run_accuracy_tests(void) +{ + static const struct { + float x; + long double log2x; + long double logex; + long double log10x; + } tests[] = { + { 0x1p-120 + 0x1p-140, + -1.19999998624139449158861798943319717e2L, + -8.31776607135195754708796206665656732e1L, + -3.61235990655024477716980559136055915e1L, + }, + { 1.0 - 0x1p-20, + -1.37586186296463416424364914705656460e-6L, + -9.53674771153890007250243736279163253e-7L, + -4.14175690642480911859354110516159131e-7L, }, + { 1.0 + 0x1p-20, + 1.37586055084113820105668028340371476e-6L, + 9.53673861659188233908415514963336144e-7L, + 4.14175295653950611453333571759200697e-7L }, + { 19.75, + 4.30378074817710292442728634194115348e0L, + 2.98315349134713087533848129856505779e0L, + 1.29556709996247903756734359702926363e0L }, + { 19.75 * 0x1p100, + 1.043037807481771029244272863419411534e2L, + 7.229787154734166181706169344438271459e1L, + 3.139856666636059855894123306947856631e1L }, + }; + int i; + + for (i = 0; i < sizeof(tests) / sizeof(tests[0]); i++) { + test_tol(log2, tests[i].x, tests[i].log2x, DBL_ULP()); + test_tol(log2f, tests[i].x, tests[i].log2x, FLT_ULP()); + test_tol(log2l, tests[i].x, tests[i].log2x, LDBL_ULP()); + test_tol(log, tests[i].x, tests[i].logex, DBL_ULP()); + test_tol(logf, tests[i].x, tests[i].logex, FLT_ULP()); + test_tol(logl, tests[i].x, tests[i].logex, LDBL_ULP()); + test_tol(log10, tests[i].x, tests[i].log10x, DBL_ULP()); + test_tol(log10f, tests[i].x, tests[i].log10x, FLT_ULP()); + test_tol(log10l, tests[i].x, tests[i].log10x, LDBL_ULP()); + if (tests[i].x >= 0.5) { + test_tol(log1p, tests[i].x - 1, tests[i].logex, + DBL_ULP()); + test_tol(log1pf, tests[i].x - 1, tests[i].logex, + FLT_ULP()); + test_tol(log1pl, tests[i].x - 1, tests[i].logex, + LDBL_ULP()); + } + } +} + +void +run_log1p_accuracy_tests(void) +{ + + test_tol(log1pf, 0x0.333333p0F, + 1.82321546859847114303367992804596800640e-1L, FLT_ULP()); + test_tol(log1p, 0x0.3333333333333p0, + 1.82321556793954589204283870982629267635e-1L, DBL_ULP()); + test_tol(log1pl, 0x0.33333333333333332p0L, + 1.82321556793954626202683007050468762914e-1L, LDBL_ULP()); + + test_tol(log1pf, -0x0.333333p0F, + -2.23143536413048672940940199918017467652e-1L, FLT_ULP()); + test_tol(log1p, -0x0.3333333333333p0, + -2.23143551314209700255143859052009022937e-1L, DBL_ULP()); + test_tol(log1pl, -0x0.33333333333333332p0L, + -2.23143551314209755752742563153765697950e-1L, LDBL_ULP()); +} + +int +main(int argc, char *argv[]) +{ + + printf("1..5\n"); + + run_generic_tests(); + printf("ok 1 - logarithm\n"); + + run_log2_tests(); + printf("ok 2 - logarithm\n"); + + run_roundingmode_tests(); + printf("ok 3 - logarithm\n"); + + run_accuracy_tests(); + printf("ok 4 - logarithm\n"); + + run_log1p_accuracy_tests(); + printf("ok 5 - logarithm\n"); + + return (0); +} |
