Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
253 lines
6.6 KiB
C
253 lines
6.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* IEEE754 floating point arithmetic
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* single precision: MAX{,A}.f
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* MAX : Scalar Floating-Point Maximum
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* MAXA: Scalar Floating-Point argument with Maximum Absolute Value
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*
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* MAX.S : FPR[fd] = maxNum(FPR[fs],FPR[ft])
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* MAXA.S: FPR[fd] = maxNumMag(FPR[fs],FPR[ft])
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*
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* MIPS floating point support
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* Copyright (C) 2015 Imagination Technologies, Ltd.
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* Author: Markos Chandras <markos.chandras@imgtec.com>
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*/
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#include "ieee754sp.h"
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union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y)
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{
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COMPXSP;
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COMPYSP;
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EXPLODEXSP;
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EXPLODEYSP;
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FLUSHXSP;
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FLUSHYSP;
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ieee754_clearcx();
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switch (CLPAIR(xc, yc)) {
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
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return ieee754sp_nanxcpt(y);
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
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return ieee754sp_nanxcpt(x);
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/*
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* Quiet NaN handling
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*/
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/*
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* The case of both inputs quiet NaNs
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*/
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
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return x;
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/*
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* The cases of exactly one input quiet NaN (numbers
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* are here preferred as returned values to NaNs)
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*/
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
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return x;
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
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return y;
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/*
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* Infinity and zero handling
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*/
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
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return xs ? y : x;
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
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return ys ? x : y;
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
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return ieee754sp_zero(xs & ys);
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
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SPDNORMX;
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fallthrough;
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
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SPDNORMY;
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break;
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
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SPDNORMX;
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}
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/* Finally get to do some computation */
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assert(xm & SP_HIDDEN_BIT);
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assert(ym & SP_HIDDEN_BIT);
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/* Compare signs */
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if (xs > ys)
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return y;
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else if (xs < ys)
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return x;
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/* Signs of inputs are equal, let's compare exponents */
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if (xs == 0) {
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/* Inputs are both positive */
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if (xe > ye)
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return x;
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else if (xe < ye)
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return y;
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} else {
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/* Inputs are both negative */
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if (xe > ye)
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return y;
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else if (xe < ye)
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return x;
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}
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/* Signs and exponents of inputs are equal, let's compare mantissas */
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if (xs == 0) {
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/* Inputs are both positive, with equal signs and exponents */
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if (xm <= ym)
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return y;
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return x;
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}
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/* Inputs are both negative, with equal signs and exponents */
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if (xm <= ym)
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return x;
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return y;
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}
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union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
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{
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COMPXSP;
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COMPYSP;
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EXPLODEXSP;
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EXPLODEYSP;
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FLUSHXSP;
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FLUSHYSP;
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ieee754_clearcx();
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switch (CLPAIR(xc, yc)) {
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
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return ieee754sp_nanxcpt(y);
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
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return ieee754sp_nanxcpt(x);
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/*
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* Quiet NaN handling
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*/
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/*
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* The case of both inputs quiet NaNs
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*/
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
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return x;
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/*
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* The cases of exactly one input quiet NaN (numbers
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* are here preferred as returned values to NaNs)
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*/
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
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return x;
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
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return y;
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/*
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* Infinity and zero handling
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*/
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
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return ieee754sp_inf(xs & ys);
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
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return x;
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
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return y;
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case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
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return ieee754sp_zero(xs & ys);
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
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SPDNORMX;
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fallthrough;
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case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
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SPDNORMY;
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break;
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case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
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SPDNORMX;
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}
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/* Finally get to do some computation */
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assert(xm & SP_HIDDEN_BIT);
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assert(ym & SP_HIDDEN_BIT);
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/* Compare exponent */
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if (xe > ye)
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return x;
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else if (xe < ye)
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return y;
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/* Compare mantissa */
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if (xm < ym)
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return y;
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else if (xm > ym)
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return x;
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else if (xs == 0)
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return x;
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return y;
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}
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