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Diffstat (limited to 'lib/msun/tests/csqrt_test.c')
| -rw-r--r-- | lib/msun/tests/csqrt_test.c | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/lib/msun/tests/csqrt_test.c b/lib/msun/tests/csqrt_test.c new file mode 100644 index 000000000000..b9ae2b3b6ae7 --- /dev/null +++ b/lib/msun/tests/csqrt_test.c @@ -0,0 +1,369 @@ +/*- + * Copyright (c) 2007 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 csqrt{,f}() + */ + +#include <sys/param.h> + +#include <complex.h> +#include <float.h> +#include <math.h> +#include <stdio.h> + +#include "test-utils.h" + +/* + * This is a test hook that can point to csqrtl(), _csqrt(), or to _csqrtf(). + * The latter two convert to float or double, respectively, and test csqrtf() + * and csqrt() with the same arguments. + */ +static long double complex (*t_csqrt)(long double complex); + +static long double complex +_csqrtf(long double complex d) +{ + + return (csqrtf((float complex)d)); +} + +static long double complex +_csqrt(long double complex d) +{ + + return (csqrt((double complex)d)); +} + +#pragma STDC CX_LIMITED_RANGE OFF + +/* + * Compare d1 and d2 using special rules: NaN == NaN and +0 != -0. + * Fail an assertion if they differ. + */ +#define assert_equal(d1, d2) CHECK_CFPEQUAL_CS(d1, d2, CS_BOTH) + +/* + * Test csqrt for some finite arguments where the answer is exact. + * (We do not test if it produces correctly rounded answers when the + * result is inexact, nor do we check whether it throws spurious + * exceptions.) + */ +static void +test_finite(void) +{ + static const double tests[] = { + /* csqrt(a + bI) = x + yI */ + /* a b x y */ + 0, 8, 2, 2, + 0, -8, 2, -2, + 4, 0, 2, 0, + -4, 0, 0, 2, + 3, 4, 2, 1, + 3, -4, 2, -1, + -3, 4, 1, 2, + -3, -4, 1, -2, + 5, 12, 3, 2, + 7, 24, 4, 3, + 9, 40, 5, 4, + 11, 60, 6, 5, + 13, 84, 7, 6, + 33, 56, 7, 4, + 39, 80, 8, 5, + 65, 72, 9, 4, + 987, 9916, 74, 67, + 5289, 6640, 83, 40, + 460766389075.0, 16762287900.0, 678910, 12345 + }; + /* + * We also test some multiples of the above arguments. This + * array defines which multiples we use. Note that these have + * to be small enough to not cause overflow for float precision + * with all of the constants in the above table. + */ + static const double mults[] = { + 1, + 2, + 3, + 13, + 16, + 0x1.p30, + 0x1.p-30, + }; + + double a, b; + double x, y; + unsigned i, j; + + for (i = 0; i < nitems(tests); i += 4) { + for (j = 0; j < nitems(mults); j++) { + a = tests[i] * mults[j] * mults[j]; + b = tests[i + 1] * mults[j] * mults[j]; + x = tests[i + 2] * mults[j]; + y = tests[i + 3] * mults[j]; + ATF_CHECK(t_csqrt(CMPLXL(a, b)) == CMPLXL(x, y)); + } + } + +} + +/* + * Test the handling of +/- 0. + */ +static void +test_zeros(void) +{ + + assert_equal(t_csqrt(CMPLXL(0.0, 0.0)), CMPLXL(0.0, 0.0)); + assert_equal(t_csqrt(CMPLXL(-0.0, 0.0)), CMPLXL(0.0, 0.0)); + assert_equal(t_csqrt(CMPLXL(0.0, -0.0)), CMPLXL(0.0, -0.0)); + assert_equal(t_csqrt(CMPLXL(-0.0, -0.0)), CMPLXL(0.0, -0.0)); +} + +/* + * Test the handling of infinities when the other argument is not NaN. + */ +static void +test_infinities(void) +{ + static const double vals[] = { + 0.0, + -0.0, + 42.0, + -42.0, + INFINITY, + -INFINITY, + }; + + unsigned i; + + for (i = 0; i < nitems(vals); i++) { + if (isfinite(vals[i])) { + assert_equal(t_csqrt(CMPLXL(-INFINITY, vals[i])), + CMPLXL(0.0, copysignl(INFINITY, vals[i]))); + assert_equal(t_csqrt(CMPLXL(INFINITY, vals[i])), + CMPLXL(INFINITY, copysignl(0.0, vals[i]))); + } + assert_equal(t_csqrt(CMPLXL(vals[i], INFINITY)), + CMPLXL(INFINITY, INFINITY)); + assert_equal(t_csqrt(CMPLXL(vals[i], -INFINITY)), + CMPLXL(INFINITY, -INFINITY)); + } +} + +/* + * Test the handling of NaNs. + */ +static void +test_nans(void) +{ + + ATF_CHECK(creall(t_csqrt(CMPLXL(INFINITY, NAN))) == INFINITY); + ATF_CHECK(isnan(cimagl(t_csqrt(CMPLXL(INFINITY, NAN))))); + + ATF_CHECK(isnan(creall(t_csqrt(CMPLXL(-INFINITY, NAN))))); + ATF_CHECK(isinf(cimagl(t_csqrt(CMPLXL(-INFINITY, NAN))))); + + assert_equal(t_csqrt(CMPLXL(NAN, INFINITY)), + CMPLXL(INFINITY, INFINITY)); + assert_equal(t_csqrt(CMPLXL(NAN, -INFINITY)), + CMPLXL(INFINITY, -INFINITY)); + + assert_equal(t_csqrt(CMPLXL(0.0, NAN)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(-0.0, NAN)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(42.0, NAN)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(-42.0, NAN)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(NAN, 0.0)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(NAN, -0.0)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(NAN, 42.0)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(NAN, -42.0)), CMPLXL(NAN, NAN)); + assert_equal(t_csqrt(CMPLXL(NAN, NAN)), CMPLXL(NAN, NAN)); +} + +/* + * Test whether csqrt(a + bi) works for inputs that are large enough to + * cause overflow in hypot(a, b) + a. Each of the tests is scaled up to + * near MAX_EXP. + */ +static void +test_overflow(int maxexp) +{ + long double a, b; + long double complex result; + int exp, i; + + ATF_CHECK(maxexp > 0 && maxexp % 2 == 0); + + for (i = 0; i < 4; i++) { + exp = maxexp - 2 * i; + + /* csqrt(115 + 252*I) == 14 + 9*I */ + a = ldexpl(115 * 0x1p-8, exp); + b = ldexpl(252 * 0x1p-8, exp); + result = t_csqrt(CMPLXL(a, b)); + ATF_CHECK_EQ(creall(result), ldexpl(14 * 0x1p-4, exp / 2)); + ATF_CHECK_EQ(cimagl(result), ldexpl(9 * 0x1p-4, exp / 2)); + + /* csqrt(-11 + 60*I) = 5 + 6*I */ + a = ldexpl(-11 * 0x1p-6, exp); + b = ldexpl(60 * 0x1p-6, exp); + result = t_csqrt(CMPLXL(a, b)); + ATF_CHECK_EQ(creall(result), ldexpl(5 * 0x1p-3, exp / 2)); + ATF_CHECK_EQ(cimagl(result), ldexpl(6 * 0x1p-3, exp / 2)); + + /* csqrt(225 + 0*I) == 15 + 0*I */ + a = ldexpl(225 * 0x1p-8, exp); + b = 0; + result = t_csqrt(CMPLXL(a, b)); + ATF_CHECK_EQ(creall(result), ldexpl(15 * 0x1p-4, exp / 2)); + ATF_CHECK_EQ(cimagl(result), 0); + } +} + +/* + * Test that precision is maintained for some large squares. Set all or + * some bits in the lower mantdig/2 bits, square the number, and try to + * recover the sqrt. Note: + * (x + xI)**2 = 2xxI + */ +static void +test_precision(int maxexp, int mantdig) +{ + long double b, x; + long double complex result; +#if LDBL_MANT_DIG <= 64 + typedef uint64_t ldbl_mant_type; +#elif LDBL_MANT_DIG <= 128 + typedef __uint128_t ldbl_mant_type; +#else +#error "Unsupported long double format" +#endif + ldbl_mant_type mantbits, sq_mantbits; + int exp, i; + + ATF_REQUIRE(maxexp > 0 && maxexp % 2 == 0); + ATF_REQUIRE(mantdig <= LDBL_MANT_DIG); + mantdig = rounddown(mantdig, 2); + + for (exp = 0; exp <= maxexp; exp += 2) { + mantbits = ((ldbl_mant_type)1 << (mantdig / 2)) - 1; + for (i = 0; i < 100 && + mantbits > ((ldbl_mant_type)1 << (mantdig / 2 - 1)); + i++, mantbits--) { + sq_mantbits = mantbits * mantbits; + /* + * sq_mantibts is a mantdig-bit number. Divide by + * 2**mantdig to normalize it to [0.5, 1), where, + * note, the binary power will be -1. Raise it by + * 2**exp for the test. exp is even. Lower it by + * one to reach a final binary power which is also + * even. The result should be exactly + * representable, given that mantdig is less than or + * equal to the available precision. + */ + b = ldexpl((long double)sq_mantbits, + exp - 1 - mantdig); + x = ldexpl(mantbits, (exp - 2 - mantdig) / 2); + CHECK_FPEQUAL(b, x * x * 2); + result = t_csqrt(CMPLXL(0, b)); + CHECK_FPEQUAL(x, creall(result)); + CHECK_FPEQUAL(x, cimagl(result)); + } + } +} + +ATF_TC_WITHOUT_HEAD(csqrt); +ATF_TC_BODY(csqrt, tc) +{ + /* Test csqrt() */ + t_csqrt = _csqrt; + + test_finite(); + + test_zeros(); + + test_infinities(); + + test_nans(); + + test_overflow(DBL_MAX_EXP); + + test_precision(DBL_MAX_EXP, DBL_MANT_DIG); +} + +ATF_TC_WITHOUT_HEAD(csqrtf); +ATF_TC_BODY(csqrtf, tc) +{ + /* Now test csqrtf() */ + t_csqrt = _csqrtf; + + test_finite(); + + test_zeros(); + + test_infinities(); + + test_nans(); + + test_overflow(FLT_MAX_EXP); + + test_precision(FLT_MAX_EXP, FLT_MANT_DIG); +} + +ATF_TC_WITHOUT_HEAD(csqrtl); +ATF_TC_BODY(csqrtl, tc) +{ + /* Now test csqrtl() */ + t_csqrt = csqrtl; + + test_finite(); + + test_zeros(); + + test_infinities(); + + test_nans(); + + test_overflow(LDBL_MAX_EXP); + + /* i386 is configured to use 53-bit rounding precision for long double. */ + test_precision(LDBL_MAX_EXP, +#ifndef __i386__ + LDBL_MANT_DIG +#else + DBL_MANT_DIG +#endif + ); +} + +ATF_TP_ADD_TCS(tp) +{ + ATF_TP_ADD_TC(tp, csqrt); + ATF_TP_ADD_TC(tp, csqrtf); + ATF_TP_ADD_TC(tp, csqrtl); + + return (atf_no_error()); +} |