| /* Set current rounding direction. |
| Copyright (C) 1997-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <fenv.h> |
| #include <unistd.h> |
| #include <ldsodefs.h> |
| #include <dl-procinfo.h> |
| |
| int |
| __fesetround (int round) |
| { |
| unsigned short int cw; |
| |
| if ((round & ~0xc00) != 0) |
| /* ROUND is no valid rounding mode. */ |
| return 1; |
| |
| __asm__ ("fnstcw %0" : "=m" (*&cw)); |
| cw &= ~0xc00; |
| cw |= round; |
| __asm__ ("fldcw %0" : : "m" (*&cw)); |
| |
| /* If the CPU supports SSE we set the MXCSR as well. */ |
| if (HAS_CPU_FEATURE (SSE)) |
| { |
| unsigned int xcw; |
| |
| __asm__ ("stmxcsr %0" : "=m" (*&xcw)); |
| xcw &= ~0x6000; |
| xcw |= round << 3; |
| __asm__ ("ldmxcsr %0" : : "m" (*&xcw)); |
| } |
| |
| return 0; |
| } |
| libm_hidden_def (__fesetround) |
| weak_alias (__fesetround, fesetround) |
| libm_hidden_weak (fesetround) |