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/*-
* 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
#define ALL_STD_EXCEPT (FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
FE_OVERFLOW | FE_UNDERFLOW)
#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(((func), fetestexcept(exceptmask) == (excepts))); \
} 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(log2, x, result, exceptmask, excepts); \
test(log2f, x, result, exceptmask, excepts); \
test(log10, x, result, exceptmask, excepts); \
test(log10f, 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); \
} while (0)
/*
* Determine whether x and y are equal, with two special rules:
* +0.0 != -0.0
* NaN == NaN
*/
int
fpequal(long double x, long double y)
{
return ((x == y && !signbit(x) == !signbit(y)) || isnan(x) && isnan(y));
}
void
run_generic_tests(void)
{
/* exp(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);
}
}
int
main(int argc, char *argv[])
{
printf("1..2\n");
run_generic_tests();
printf("ok 1 - logarithm\n");
run_log2_tests();
printf("ok 2 - logarithm\n");
return (0);
}
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