[PATCH v2 17/25] math: Use acoshf from CORE-MATH
DJ Delorie
dj@redhat.com
Sat Dec 7 03:41:27 GMT 2024
Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:
> The CORE-MATH implementation is correctly rounded (for any rounding mode)
> and shows slight better performance to the generic acoshf.
One spot that could use a comment, but otherwise LGTM
Reviewed-by: DJ Delorie <dj@redhat.com>
> diff --git a/SHARED-FILES b/SHARED-FILES
> index 3d32f0f3b6..c29c1c8106 100644
> --- a/SHARED-FILES
> +++ b/SHARED-FILES
> @@ -298,3 +298,7 @@ sysdeps/ieee754/flt-32/e_acosf.c:
> (src/binary32/acos/acosf.c in CORE-MATH)
> - The code was adapted to use glibc code style and internal
> functions to handle errno, overflow, and underflow.
> +sysdeps/ieee754/flt-32/e_acoshf.c:
> + (src/binary32/acosh/acoshf.c in CORE-MATH)
> + - The code was adapted to use glibc code style and internal
> + functions to handle errno, overflow, and underflow.
Ok.
> diff --git a/sysdeps/aarch64/libm-test-ulps b/sysdeps/aarch64/libm-test-ulps
> diff --git a/sysdeps/alpha/fpu/libm-test-ulps b/sysdeps/alpha/fpu/libm-test-ulps
> diff --git a/sysdeps/arc/fpu/libm-test-ulps b/sysdeps/arc/fpu/libm-test-ulps
> diff --git a/sysdeps/arc/nofpu/libm-test-ulps b/sysdeps/arc/nofpu/libm-test-ulps
> diff --git a/sysdeps/arm/libm-test-ulps b/sysdeps/arm/libm-test-ulps
> diff --git a/sysdeps/csky/fpu/libm-test-ulps b/sysdeps/csky/fpu/libm-test-ulps
> diff --git a/sysdeps/csky/nofpu/libm-test-ulps b/sysdeps/csky/nofpu/libm-test-ulps
> diff --git a/sysdeps/hppa/fpu/libm-test-ulps b/sysdeps/hppa/fpu/libm-test-ulps
Ok.
> diff --git a/sysdeps/i386/fpu/e_acoshf.S b/sysdeps/i386/fpu/e_acoshf.S
> deleted file mode 100644
Ok.
> diff --git a/sysdeps/ieee754/flt-32/e_acoshf.c b/sysdeps/ieee754/flt-32/e_acoshf.c
> index 2237af4ba4..37e5e2071b 100644
> --- a/sysdeps/ieee754/flt-32/e_acoshf.c
> +++ b/sysdeps/ieee754/flt-32/e_acoshf.c
> @@ -1,49 +1,201 @@
> -/* e_acoshf.c -- float version of e_acosh.c.
> - */
> -
> -/*
> - * ====================================================
> - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
> - *
> - * Developed at SunPro, a Sun Microsystems, Inc. business.
> - * Permission to use, copy, modify, and distribute this
> - * software is freely granted, provided that this notice
> - * is preserved.
> - * ====================================================
> - */
> -
> -#if defined(LIBM_SCCS) && !defined(lint)
> -static char rcsid[] = "$NetBSD: e_acoshf.c,v 1.5 1995/05/12 04:57:20 jtc Exp $";
> -#endif
> +/* Correctly-rounded inverse hyperbolic cosine function for binary32 format.
> +
> +Copyright (c) 2023-2024 Alexei Sibidanov.
> +
> +The original version of this file was copied from the CORE-MATH
> +project (file src/binary32/acosh/acoshf.c, revision 927eb45).
> +
> +Permission is hereby granted, free of charge, to any person obtaining a copy
> +of this software and associated documentation files (the "Software"), to deal
> +in the Software without restriction, including without limitation the rights
> +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> +copies of the Software, and to permit persons to whom the Software is
> +furnished to do so, subject to the following conditions:
> +
> +The above copyright notice and this permission notice shall be included in all
> +copies or substantial portions of the Software.
> +
> +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> +SOFTWARE.
> +*/
>
> #include <math.h>
> -#include <math_private.h>
> +#include <stdint.h>
> #include <libm-alias-finite.h>
> +#include "math_config.h"
Ok.
> -static const float
> -one = 1.0,
> -ln2 = 6.9314718246e-01; /* 0x3f317218 */
Ok.
> +static __attribute__ ((noinline)) float
> +as_special (float x)
> +{
> + uint32_t t = asuint (x);
> + if (t == 0x3f800000u)
> + return 0.0f;
> + if ((t << 1) > 0xff000000u)
> + return x + x; /* nan */
> + if (t == 0x7f800000u)
> + return x; /* inf */
> + return __math_invalidf (x);
> +}
>
> -float __ieee754_acoshf(float x)
> +float
> +__ieee754_acoshf (float x)
Ok.
> {
> - float t;
> - int32_t hx;
> - GET_FLOAT_WORD(hx,x);
> - if(hx<0x3f800000) { /* x < 1 */
> - return (x-x)/(x-x);
> - } else if(hx >=0x4d800000) { /* x > 2**28 */
> - if(hx >=0x7f800000) { /* x is inf of NaN */
> - return x+x;
> - } else
> - return __ieee754_logf(x)+ln2; /* acosh(huge)=log(2x) */
> - } else if (hx==0x3f800000) {
> - return 0.0; /* acosh(1) = 0 */
> - } else if (hx > 0x40000000) { /* 2**28 > x > 2 */
> - t=x*x;
> - return __ieee754_logf((float)2.0*x-one/(x+sqrtf(t-one)));
> - } else { /* 1<x<2 */
> - t = x-one;
> - return __log1pf(t+sqrtf((float)2.0*t+t*t));
Ok.
> + static const double ix[] =
> + {
> + 0x1p+0, 0x1.fc07f01fcp-1, 0x1.f81f81f82p-1, 0x1.f44659e4ap-1,
> + 0x1.f07c1f07cp-1, 0x1.ecc07b302p-1, 0x1.e9131abfp-1, 0x1.e573ac902p-1,
> + 0x1.e1e1e1e1ep-1, 0x1.de5d6e3f8p-1, 0x1.dae6076bap-1, 0x1.d77b654b8p-1,
> + 0x1.d41d41d42p-1, 0x1.d0cb58f6ep-1, 0x1.cd8568904p-1, 0x1.ca4b3055ep-1,
> + 0x1.c71c71c72p-1, 0x1.c3f8f01c4p-1, 0x1.c0e070382p-1, 0x1.bdd2b8994p-1,
> + 0x1.bacf914c2p-1, 0x1.b7d6c3ddap-1, 0x1.b4e81b4e8p-1, 0x1.b2036406cp-1,
> + 0x1.af286bca2p-1, 0x1.ac5701ac6p-1, 0x1.a98ef606ap-1, 0x1.a6d01a6dp-1,
> + 0x1.a41a41a42p-1, 0x1.a16d3f97ap-1, 0x1.9ec8e951p-1, 0x1.9c2d14ee4p-1,
> + 0x1.99999999ap-1, 0x1.970e4f80cp-1, 0x1.948b0fcd6p-1, 0x1.920fb49dp-1,
> + 0x1.8f9c18f9cp-1, 0x1.8d3018d3p-1, 0x1.8acb90f6cp-1, 0x1.886e5f0acp-1,
> + 0x1.861861862p-1, 0x1.83c977ab2p-1, 0x1.818181818p-1, 0x1.7f405fd02p-1,
> + 0x1.7d05f417ep-1, 0x1.7ad2208ep-1, 0x1.78a4c8178p-1, 0x1.767dce434p-1,
> + 0x1.745d1745ep-1, 0x1.724287f46p-1, 0x1.702e05c0cp-1, 0x1.6e1f76b44p-1,
> + 0x1.6c16c16c2p-1, 0x1.6a13cd154p-1, 0x1.681681682p-1, 0x1.661ec6a52p-1,
> + 0x1.642c8590cp-1, 0x1.623fa7702p-1, 0x1.605816058p-1, 0x1.5e75bb8dp-1,
> + 0x1.5c9882b94p-1, 0x1.5ac056b02p-1, 0x1.58ed23082p-1, 0x1.571ed3c5p-1,
> + 0x1.555555556p-1, 0x1.5390948f4p-1, 0x1.51d07eae2p-1, 0x1.501501502p-1,
> + 0x1.4e5e0a73p-1, 0x1.4cab88726p-1, 0x1.4afd6a052p-1, 0x1.49539e3b2p-1,
> + 0x1.47ae147aep-1, 0x1.460cbc7f6p-1, 0x1.446f86562p-1, 0x1.42d6625d6p-1,
> + 0x1.414141414p-1, 0x1.3fb013fbp-1, 0x1.3e22cbce4p-1, 0x1.3c995a47cp-1,
> + 0x1.3b13b13b2p-1, 0x1.3991c2c18p-1, 0x1.381381382p-1, 0x1.3698df3dep-1,
> + 0x1.3521cfb2cp-1, 0x1.33ae45b58p-1, 0x1.323e34a2cp-1, 0x1.30d19013p-1,
> + 0x1.2f684bda2p-1, 0x1.2e025c04cp-1, 0x1.2c9fb4d82p-1, 0x1.2b404ad02p-1,
> + 0x1.29e4129e4p-1, 0x1.288b01288p-1, 0x1.27350b882p-1, 0x1.25e22708p-1,
> + 0x1.24924924ap-1, 0x1.23456789ap-1, 0x1.21fb78122p-1, 0x1.20b470c68p-1,
> + 0x1.1f7047dc2p-1, 0x1.1e2ef3b4p-1, 0x1.1cf06ada2p-1, 0x1.1bb4a4046p-1,
> + 0x1.1a7b9611ap-1, 0x1.19453808cp-1, 0x1.181181182p-1, 0x1.16e068942p-1,
> + 0x1.15b1e5f76p-1, 0x1.1485f0e0ap-1, 0x1.135c81136p-1, 0x1.12358e75ep-1,
> + 0x1.111111112p-1, 0x1.0fef010fep-1, 0x1.0ecf56be6p-1, 0x1.0db20a89p-1,
> + 0x1.0c9714fbcp-1, 0x1.0b7e6ec26p-1, 0x1.0a6810a68p-1, 0x1.0953f3902p-1,
> + 0x1.084210842p-1, 0x1.073260a48p-1, 0x1.0624dd2f2p-1, 0x1.05197f7d8p-1,
> + 0x1.041041042p-1, 0x1.03091b52p-1, 0x1.020408102p-1, 0x1.01010101p-1,
> + 0x1p-1
> + };
> +
> + static const double lix[] =
> + {
> + 0x0p+0, 0x1.fe02a6b146789p-8, 0x1.fc0a8b0fa03e4p-7,
> + 0x1.7b91b07de311bp-6, 0x1.f829b0e7c33p-6, 0x1.39e87b9fd7d6p-5,
> + 0x1.77458f63edcfcp-5, 0x1.b42dd7117b1bfp-5, 0x1.f0a30c01362a6p-5,
> + 0x1.16536eea7fae1p-4, 0x1.341d7961791d1p-4, 0x1.51b073f07983fp-4,
> + 0x1.6f0d28ae3eb4cp-4, 0x1.8c345d6383b21p-4, 0x1.a926d3a475563p-4,
> + 0x1.c5e548f63a743p-4, 0x1.e27076e28f2e6p-4, 0x1.fec9131dbaabbp-4,
> + 0x1.0d77e7ccf6e59p-3, 0x1.1b72ad52f87ap-3, 0x1.29552f81eb523p-3,
> + 0x1.371fc201f7f74p-3, 0x1.44d2b6ccbfd1ep-3, 0x1.526e5e3a41438p-3,
> + 0x1.5ff3070a613d4p-3, 0x1.6d60fe717221dp-3, 0x1.7ab890212b909p-3,
> + 0x1.87fa065214911p-3, 0x1.9525a9cf296b4p-3, 0x1.a23bc1fe42563p-3,
> + 0x1.af3c94e81bff3p-3, 0x1.bc2867430acd6p-3, 0x1.c8ff7c7989a22p-3,
> + 0x1.d5c216b535b91p-3, 0x1.e27076e2f92e6p-3, 0x1.ef0adcbe0d936p-3,
> + 0x1.fb9186d5ebe2bp-3, 0x1.0402594b51041p-2, 0x1.0a324e27370e3p-2,
> + 0x1.1058bf9ad7ad5p-2, 0x1.1675cabaa660ep-2, 0x1.1c898c16b91fbp-2,
> + 0x1.22941fbcfb966p-2, 0x1.2895a13dd2ea3p-2, 0x1.2e8e2bade7d31p-2,
> + 0x1.347dd9a9afd55p-2, 0x1.3a64c556b05eap-2, 0x1.40430868877e4p-2,
> + 0x1.4618bc219dec2p-2, 0x1.4be5f9579e0a1p-2, 0x1.51aad872c982dp-2,
> + 0x1.5767717432a6cp-2, 0x1.5d1bdbf5669cap-2, 0x1.62c82f2b83795p-2,
> + 0x1.686c81e9964afp-2, 0x1.6e08eaa2929e4p-2, 0x1.739d7f6b95007p-2,
> + 0x1.792a55fdb7fa2p-2, 0x1.7eaf83b82efc3p-2, 0x1.842d1da1ecb17p-2,
> + 0x1.89a3386be825bp-2, 0x1.8f11e87347ac7p-2, 0x1.947941c1f26fbp-2,
> + 0x1.99d958119208bp-2, 0x1.9f323ecbd984cp-2, 0x1.a484090e5eb0ap-2,
> + 0x1.a9cec9a9cf84ap-2, 0x1.af1293245606bp-2, 0x1.b44f77bc98f63p-2,
> + 0x1.b9858969218fbp-2, 0x1.beb4d9da96b7cp-2, 0x1.c3dd7a7d0354dp-2,
> + 0x1.c8ff7c79ada22p-2, 0x1.ce1af0b855bebp-2, 0x1.d32fe7e039bd5p-2,
> + 0x1.d83e72587673ep-2, 0x1.dd46a04c204a1p-2, 0x1.e24881a7cac26p-2,
> + 0x1.e744261d8a788p-2, 0x1.ec399d2457ccp-2, 0x1.f128f5fac86edp-2,
> + 0x1.f6123fa71c8acp-2, 0x1.faf588f76631fp-2, 0x1.ffd2e08580c98p-2,
> + 0x1.02552a5a4f0ffp-1, 0x1.04bdf9da8b6d2p-1, 0x1.0723e5c1b4f4p-1,
> + 0x1.0986f4f589521p-1, 0x1.0be72e423ca83p-1, 0x1.0e44985d0f48cp-1,
> + 0x1.109f39e2be497p-1, 0x1.12f71959283bcp-1, 0x1.154c3d2f4f5eap-1,
> + 0x1.179eabbd9c9a1p-1, 0x1.19ee6b466516fp-1, 0x1.1c3b81f723c25p-1,
> + 0x1.1e85f5e6ec0dp-1, 0x1.20cdcd193f76ep-1, 0x1.23130d7beb743p-1,
> + 0x1.2555bce9887cbp-1, 0x1.2795e1288211bp-1, 0x1.29d37fec2308bp-1,
> + 0x1.2c0e9ed45768cp-1, 0x1.2e47436e5ae68p-1, 0x1.307d7334ff0bep-1,
> + 0x1.32b1339134571p-1, 0x1.34e289d9b39d3p-1, 0x1.37117b5481bb6p-1,
> + 0x1.393e0d3549a1ap-1, 0x1.3b6844a017823p-1, 0x1.3d9026a70eefbp-1,
> + 0x1.3fb5b84cfeb42p-1, 0x1.41d8fe844b2aep-1, 0x1.43f9fe2fb9267p-1,
> + 0x1.4618bc21d86c2p-1, 0x1.48353d1e928dfp-1, 0x1.4a4f85db1debbp-1,
> + 0x1.4c679afcc323ap-1, 0x1.4e7d811b77bb1p-1, 0x1.50913cbff8c6bp-1,
> + 0x1.52a2d265be5abp-1, 0x1.54b2467998498p-1, 0x1.56bf9d5b34b99p-1,
> + 0x1.58cadb5cbe989p-1, 0x1.5ad404c33af2dp-1, 0x1.5cdb1dc6ad765p-1,
> + 0x1.5ee02a9241e75p-1, 0x1.60e32f447a8d9p-1, 0x1.62e42fefa39efp-1
> + };
Ok.
> +
> + uint32_t t = asuint (x);
> + if (__glibc_unlikely (t <= 0x3f800000u))
> + return as_special (x);
Ok.
> + else if (__glibc_unlikely (t <= 0x3f99db23u)) /* x <= 0x1.33b646p+0 */
> + {
> + float zf = x - 1.0f;
> + double z = zf;
> + double a = sqrt (2.0 * z);
> + static const double c[] =
> + {
> + -0x1.555555555491ep-4, 0x1.333333319c2p-6,
> + -0x1.6db6da26e5e0ep-8, 0x1.f1c698b7100cep-10,
> + -0x1.6e7ca9e152dc2p-11, 0x1.1b4cf187158bdp-12,
> + -0x1.b5137f11a88e5p-14, 0x1.056c6c57152b2p-15
> + };
> + double z2 = z * z;
> + double z4 = z2 * z2;
> + double f = ((c[0] + z * c[1]) + z2 * (c[2] + z * c[3]))
> + + z4 * ((c[4] + z * c[5]) + z2 * (c[6] + z * c[7]));
> + double r = a + (a * z) * f;
> + return r;
> + }
Ok.
> + else if (__glibc_likely (t < 0x7f800000u))
> + {
> + double xd = x;
> + double x2 = xd * xd;
> + uint64_t tp = asuint64 (xd + sqrt (x2 - 1));
> + uint64_t m = tp & (~UINT64_C(0) >> 12);
> + int j = (m + (UINT64_C(1) << (52 - 8))) >> (52 - 7);
> + int e = (tp >> 52) - 0x3ff;
> + double w = asdouble (m | UINT64_C(0x3ff) << 52);
> + double z = w * ix[j] - 1.0;
Ok.
> + static const double c[] =
> + {
> + 0x1.0000000066947p+0, -0x1.00007f053d8cbp-1, 0x1.555280111d914p-2
> + };
Ok.
> + double z2 = z * z;
> + double r = ((lix[128] * e + lix[j]) + z * c[0])
> + + z2 * (c[1] + z * c[2]);
Ok
> + if (__glibc_unlikely (((asuint64 (r) + 259000) & INT64_C(0xfffffff))
> + < 260000))
This could use a comment ;-)
> + {
> + static const double cp[] =
> + {
> + 0x1p+0, -0x1p-1,
> + 0x1.55555555030bcp-2, -0x1.ffffffff2b4e5p-3,
> + 0x1.999b5076a42f2p-3, -0x1.55570c45a647dp-3
> + };
> + z2 = z * z;
> + double c0 = cp[0] + z * cp[1];
> + double c2 = cp[2] + z * cp[3];
> + double c4 = cp[4] + z * cp[5];
> + c0 += z2 * (c2 + z2 * c4);
> + const double ln2l = 0x1.7f7d1cf79abcap-20;
> + const double ln2h = 0x1.62e4p-1;
> + double Lh = ln2h * e;
> + double Ll = ln2l * e;
> + r = fma (z, c0, Ll + lix[j]) + Lh;
> + if (__glibc_unlikely ((asuint64 (r) & UINT64_C(0xfffffff)) == 0))
> + {
> + double h = fma (z, c0, Ll + lix[j]) + (Lh - r);
> + r = r + 64.0 * h;
> + }
> }
> + return r;
> + }
> + else
> + return as_special (x);
> }
> libm_alias_finite (__ieee754_acoshf, __acoshf)
Ok.
> diff --git a/sysdeps/loongarch/lp64/libm-test-ulps b/sysdeps/loongarch/lp64/libm-test-ulps
> diff --git a/sysdeps/m68k/m680x0/fpu/libm-test-ulps b/sysdeps/m68k/m680x0/fpu/libm-test-ulps
> diff --git a/sysdeps/microblaze/libm-test-ulps b/sysdeps/microblaze/libm-test-ulps
> diff --git a/sysdeps/mips/mips32/libm-test-ulps b/sysdeps/mips/mips32/libm-test-ulps
> diff --git a/sysdeps/mips/mips64/libm-test-ulps b/sysdeps/mips/mips64/libm-test-ulps
> diff --git a/sysdeps/or1k/fpu/libm-test-ulps b/sysdeps/or1k/fpu/libm-test-ulps
> diff --git a/sysdeps/or1k/nofpu/libm-test-ulps b/sysdeps/or1k/nofpu/libm-test-ulps
> diff --git a/sysdeps/powerpc/fpu/libm-test-ulps b/sysdeps/powerpc/fpu/libm-test-ulps
> diff --git a/sysdeps/powerpc/nofpu/libm-test-ulps b/sysdeps/powerpc/nofpu/libm-test-ulps
> diff --git a/sysdeps/riscv/nofpu/libm-test-ulps b/sysdeps/riscv/nofpu/libm-test-ulps
> diff --git a/sysdeps/riscv/rvd/libm-test-ulps b/sysdeps/riscv/rvd/libm-test-ulps
> diff --git a/sysdeps/s390/fpu/libm-test-ulps b/sysdeps/s390/fpu/libm-test-ulps
> diff --git a/sysdeps/sh/libm-test-ulps b/sysdeps/sh/libm-test-ulps
> diff --git a/sysdeps/sparc/fpu/libm-test-ulps b/sysdeps/sparc/fpu/libm-test-ulps
> diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps
Ok.
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