diff options
Diffstat (limited to 'lib/msun/src')
| -rw-r--r-- | lib/msun/src/s_csqrt.c | 104 | ||||
| -rw-r--r-- | lib/msun/src/s_csqrtf.c | 88 |
2 files changed, 192 insertions, 0 deletions
diff --git a/lib/msun/src/s_csqrt.c b/lib/msun/src/s_csqrt.c new file mode 100644 index 0000000..3b1e187 --- /dev/null +++ b/lib/msun/src/s_csqrt.c @@ -0,0 +1,104 @@ +/*- + * 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <complex.h> +#include <math.h> + +#include "math_private.h" + +/* + * gcc doesn't implement complex multiplication or division correctly, + * so we need to handle infinities specially. We turn on this pragma to + * notify conforming c99 compilers that the fast-but-incorrect code that + * gcc generates is acceptable, since the special cases have already been + * handled. + */ +#pragma STDC CX_LIMITED_RANGE on + +/* We risk spurious overflow for components >= DBL_MAX/(1+sqrt(2)) */ +#define THRESH 0x1.a827999fcef32p+1022 + +double complex +csqrt(double complex z) +{ + double a = creal(z), b = cimag(z); + double t; + double complex result; + int scale; + + /* Handle special cases. */ + if (z == 0) + return (cpack(0, b)); + if (isinf(b)) + return (cpack(INFINITY, b)); + if (isnan(a)) { + t = (b - b) / (b - b); /* raise invalid if b is not a NaN */ + return (cpack(t, t)); /* return NaN + NaN i */ + } + if (isinf(a)) { + /* + * csqrt(inf + nan i) = inf + nan i + * csqrt(inf + y i) = inf + 0 i + * csqrt(-inf + nan i) = nan +- inf i + * csqrt(-inf + y i) = 0 + inf i + */ + if (signbit(a)) + return (cpack(fabs(b - b), copysign(a, b))); + else + return (cpack(a, copysign(b - b, b))); + } + /* + * The remaining special case (b is NaN) is handled just fine by + * the normal code path below. + */ + + /* Scale to avoid overflow. */ + if (a >= THRESH || b >= THRESH) { + a *= 0.25; + b *= 0.25; + scale = 1; + } else { + scale = 0; + } + + /* Algorithm 312, CACM vol 10, Oct 1967 */ + if (a >= 0) { + t = sqrt((a + hypot(a, b)) * 0.5); + result = cpack(t, b / (2 * t)); + } else { + t = sqrt((-a + hypot(a, b)) * 0.5); + result = cpack(fabs(b) / (2 * t), copysign(t, b)); + } + + /* Rescale */ + if (scale) + return (result * 2); + else + return (result); +} diff --git a/lib/msun/src/s_csqrtf.c b/lib/msun/src/s_csqrtf.c new file mode 100644 index 0000000..cc5485a --- /dev/null +++ b/lib/msun/src/s_csqrtf.c @@ -0,0 +1,88 @@ +/*- + * 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <complex.h> +#include <math.h> + +#include "math_private.h" + +/* + * gcc doesn't implement complex multiplication or division correctly, + * so we need to handle infinities specially. We turn on this pragma to + * notify conforming c99 compilers that the fast-but-incorrect code that + * gcc generates is acceptable, since the special cases have already been + * handled. + */ +#pragma STDC CX_LIMITED_RANGE on + +float complex +csqrtf(float complex z) +{ + float a = crealf(z), b = cimagf(z); + double t; + + /* Handle special cases. */ + if (z == 0) + return (cpackf(0, b)); + if (isinf(b)) + return (cpackf(INFINITY, b)); + if (isnan(a)) { + t = (b - b) / (b - b); /* raise invalid if b is not a NaN */ + return (cpackf(t, t)); /* return NaN + NaN i */ + } + if (isinf(a)) { + /* + * csqrtf(inf + nan i) = inf + nan i + * csqrtf(inf + y i) = inf + 0 i + * csqrtf(-inf + nan i) = nan +- inf i + * csqrtf(-inf + y i) = 0 + inf i + */ + if (signbit(a)) + return (cpackf(fabsf(b - b), copysignf(a, b))); + else + return (cpackf(a, copysignf(b - b, b))); + } + /* + * The remaining special case (b is NaN) is handled just fine by + * the normal code path below. + */ + + /* + * We compute t in double precision to avoid overflow and to + * provide correct rounding in nearly all cases. + * This is Algorithm 312, CACM vol 10, Oct 1967. + */ + if (a >= 0) { + t = sqrt((a + hypot(a, b)) * 0.5); + return (cpackf(t, b / (2.0 * t))); + } else { + t = sqrt((-a + hypot(a, b)) * 0.5); + return (cpackf(fabsf(b) / (2.0 * t), copysignf(t, b))); + } +} |
