1 /* Set current rounding direction. 2 Copyright (C) 2000-2022 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 <fenv.h> 20 21 int __fesetround(int round)22__fesetround (int round) 23 { 24 union { unsigned long long l; unsigned int sw[2]; } s; 25 26 if (round & ~FE_DOWNWARD) 27 /* round is not a valid rounding mode. */ 28 return 1; 29 30 /* Get the current status word. */ 31 __asm__ ("fstd %%fr0,0(%1)" : "=m" (s.l) : "r" (&s.l) : "%r0"); 32 s.sw[0] &= ~FE_DOWNWARD; 33 s.sw[0] |= round & FE_DOWNWARD; 34 __asm__ ("fldd 0(%0),%%fr0" : : "r" (&s.l), "m" (s.l) : "%r0"); 35 36 return 0; 37 } 38 39 libm_hidden_def (__fesetround) 40 weak_alias (__fesetround, fesetround) 41 libm_hidden_weak (fesetround) 42