diff options
Diffstat (limited to 'arch/mips/math-emu/dp_fmin.c')
| -rw-r--r-- | arch/mips/math-emu/dp_fmin.c | 95 |
1 files changed, 67 insertions, 28 deletions
diff --git a/arch/mips/math-emu/dp_fmin.c b/arch/mips/math-emu/dp_fmin.c index c1072b0dfb95..35ded4c45989 100644 --- a/arch/mips/math-emu/dp_fmin.c +++ b/arch/mips/math-emu/dp_fmin.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * IEEE754 floating point arithmetic * double precision: MIN{,A}.f @@ -10,10 +11,6 @@ * MIPS floating point support * Copyright (C) 2015 Imagination Technologies, Ltd. * Author: Markos Chandras <markos.chandras@imgtec.com> - * - * This program is free software; you can distribute it and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation; version 2 of the License. */ #include "ieee754dp.h" @@ -47,14 +44,26 @@ union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y) case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF): return ieee754dp_nanxcpt(x); - /* numbers are preferred to NaNs */ + /* + * Quiet NaN handling + */ + + /* + * The case of both inputs quiet NaNs + */ + case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN): + return x; + + /* + * The cases of exactly one input quiet NaN (numbers + * are here preferred as returned values to NaNs) + */ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN): return x; - case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM): @@ -80,13 +89,11 @@ union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y) return ys ? y : x; case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO): - if (xs == ys) - return x; - return ieee754dp_zero(1); + return ieee754dp_zero(xs | ys); case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM): DPDNORMX; - + fallthrough; case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM): DPDNORMY; break; @@ -106,16 +113,32 @@ union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y) else if (xs < ys) return y; - /* Compare exponent */ - if (xe > ye) - return y; - else if (xe < ye) - return x; + /* Signs of inputs are the same, let's compare exponents */ + if (xs == 0) { + /* Inputs are both positive */ + if (xe > ye) + return y; + else if (xe < ye) + return x; + } else { + /* Inputs are both negative */ + if (xe > ye) + return x; + else if (xe < ye) + return y; + } - /* Compare mantissa */ + /* Signs and exponents of inputs are equal, let's compare mantissas */ + if (xs == 0) { + /* Inputs are both positive, with equal signs and exponents */ + if (xm <= ym) + return x; + return y; + } + /* Inputs are both negative, with equal signs and exponents */ if (xm <= ym) - return x; - return y; + return y; + return x; } union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y) @@ -147,14 +170,26 @@ union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y) case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF): return ieee754dp_nanxcpt(x); - /* numbers are preferred to NaNs */ + /* + * Quiet NaN handling + */ + + /* + * The case of both inputs quiet NaNs + */ + case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN): + return x; + + /* + * The cases of exactly one input quiet NaN (numbers + * are here preferred as returned values to NaNs) + */ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN): return x; - case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM): case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM): @@ -164,29 +199,29 @@ union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y) /* * Infinity and zero handling */ + case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): + return ieee754dp_inf(xs | ys); + case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM): case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): - return x; + return y; - case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM): case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM): - return y; + return x; case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO): - if (xs == ys) - return x; - return ieee754dp_zero(1); + return ieee754dp_zero(xs | ys); case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM): DPDNORMX; - + fallthrough; case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM): DPDNORMY; break; @@ -207,7 +242,11 @@ union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y) return x; /* Compare mantissa */ - if (xm <= ym) + if (xm < ym) + return x; + else if (xm > ym) + return y; + else if (xs == 1) return x; return y; } |