From: Aurelien Jarno Date: Tue, 2 Jan 2018 08:55:48 +0000 (+0100) Subject: Remove alpha specific fmax, fmin to fix sNaN handling [BZ #22660] X-Git-Tag: glibc-2.27~202 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6a9dd7a7c506a215952cd355505bad5b276e42e8;p=thirdparty%2Fglibc.git Remove alpha specific fmax, fmin to fix sNaN handling [BZ #22660] Various fmax and fmin function implementations mishandle sNaN arguments: (a) When both arguments are NaNs, the return value should be a qNaN, but sometimes it is an sNaN if at least one argument is an sNaN. (b) Under TS 18661-1 semantics, if either argument is an sNaN then the result should be a qNaN (whereas if one argument is a qNaN and the other is not a NaN, the result should be the non-NaN argument). Various implementations treat sNaNs like qNaNs here. One way to fix that is to detect the sNaN and add a special case. That said there is no FPU instruction to do that, so it requires transfering the FP value to an integer register and testing bits. This becomes quite complicated so it's probably better to just use the generic versions of these functions which just do that through issignaling. Changelog: [BZ #22660] * sysdeps/alpha/fpu/s_fmax.S: Remove file. * sysdeps/alpha/fpu/s_fmaxf.S: Likewise. * sysdeps/alpha/fpu/s_fmin.S: Likewise. * sysdeps/alpha/fpu/s_fminf.S: Likewise. --- diff --git a/ChangeLog b/ChangeLog index 5452e6f8187..9e47b8185f0 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2018-01-02 Aurelien Jarno + + [BZ #22660] + * sysdeps/alpha/fpu/s_fmax.S: Remove file. + * sysdeps/alpha/fpu/s_fmaxf.S: Likewise. + * sysdeps/alpha/fpu/s_fmin.S: Likewise. + * sysdeps/alpha/fpu/s_fminf.S: Likewise. + 2018-01-01 Dmitry V. Levin [BZ #22433] diff --git a/sysdeps/alpha/fpu/s_fmax.S b/sysdeps/alpha/fpu/s_fmax.S deleted file mode 100644 index 10a45db0d1a..00000000000 --- a/sysdeps/alpha/fpu/s_fmax.S +++ /dev/null @@ -1,52 +0,0 @@ -/* Copyright (C) 2007-2018 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Richard Henderson. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library. If not, see - . */ - -#include -#include -#include -#include - - .set noat - .set noreorder - - .text -ENTRY (__fmax) - .prologue 0 - - cmptun/su $f16, $f16, $f10 - cmptun/su $f17, $f17, $f11 - fmov $f17, $f0 - unop - - trapb - fbne $f10, $ret - fmov $f16, $f0 - fbne $f11, $ret - - cmptlt/su $f16, $f17, $f11 - trapb - fcmovne $f11, $f17, $f0 -$ret: ret - -END (__fmax) - -/* Given the in-register format of single-precision, this works there too. */ -strong_alias (__fmax, __fmaxf) -libm_alias_float (__fmax, fmax) - -libm_alias_double (__fmax, fmax) diff --git a/sysdeps/alpha/fpu/s_fmaxf.S b/sysdeps/alpha/fpu/s_fmaxf.S deleted file mode 100644 index 3c2d62bb816..00000000000 --- a/sysdeps/alpha/fpu/s_fmaxf.S +++ /dev/null @@ -1 +0,0 @@ -/* __fmaxf is in s_fmax.c */ diff --git a/sysdeps/alpha/fpu/s_fmin.S b/sysdeps/alpha/fpu/s_fmin.S deleted file mode 100644 index 4015a108174..00000000000 --- a/sysdeps/alpha/fpu/s_fmin.S +++ /dev/null @@ -1,52 +0,0 @@ -/* Copyright (C) 2007-2018 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Richard Henderson. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library. If not, see - . */ - -#include -#include -#include -#include - - .set noat - .set noreorder - - .text -ENTRY (__fmin) - .prologue 0 - - cmptun/su $f16, $f16, $f10 - cmptun/su $f17, $f17, $f11 - fmov $f17, $f0 - unop - - trapb - fbne $f10, $ret - fmov $f16, $f0 - fbne $f11, $ret - - cmptlt/su $f17, $f16, $f11 - trapb - fcmovne $f11, $f17, $f0 -$ret: ret - -END (__fmin) - -/* Given the in-register format of single-precision, this works there too. */ -strong_alias (__fmin, __fminf) -libm_alias_float (__fmin, fmin) - -libm_alias_double (__fmin, fmin) diff --git a/sysdeps/alpha/fpu/s_fminf.S b/sysdeps/alpha/fpu/s_fminf.S deleted file mode 100644 index 10ab7fe53cb..00000000000 --- a/sysdeps/alpha/fpu/s_fminf.S +++ /dev/null @@ -1 +0,0 @@ -/* __fminf is in s_fmin.c */