1/* Compute maximum of two numbers, regarding NaN as missing argument. 2 Copyright (C) 1997-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19#include <sysdep.h> 20#include <libm-alias-ldouble.h> 21 22 .text 23ENTRY(__fmaxl) 24 fldt 4(%esp) // x 25 fldt 16(%esp) // x : y 26 27 fucomi %st(1), %st 28 jp 2f 29 fcmovb %st(1), %st 30 31 fstp %st(1) 32 33 ret 34 352: // Unordered. 36 fucomi %st(0), %st 37 jp 3f 38 // st(1) is a NaN; st(0) is not. Test if st(1) is signaling. 39 testb $0x40, 11(%esp) 40 jz 4f 41 fstp %st(1) 42 ret 43 443: // st(0) is a NaN; st(1) may or may not be. 45 fxch 46 fucomi %st(0), %st 47 jp 4f 48 // st(1) is a NaN; st(0) is not. Test if st(1) is signaling. 49 testb $0x40, 23(%esp) 50 jz 4f 51 fstp %st(1) 52 ret 53 544: // Both arguments are NaNs, or one is a signaling NaN. 55 faddp 56 ret 57END(__fmaxl) 58libm_alias_ldouble (__fmax, fmax) 59