1 /* mpfr_fms -- Floating multiply-subtract 2 3 Copyright 2001-2002, 2004, 2006-2020 Free Software Foundation, Inc. 4 Contributed by the AriC and Caramba projects, INRIA. 5 6 This file is part of the GNU MPFR Library. 7 8 The GNU MPFR Library is free software; you can redistribute it and/or modify 9 it under the terms of the GNU Lesser General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or (at your 11 option) any later version. 12 13 The GNU MPFR Library is distributed in the hope that it will be useful, but 14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16 License for more details. 17 18 You should have received a copy of the GNU Lesser General Public License 19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20 https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23 #include "mpfr-impl.h" 24 25 /* The fused-multiply-subtract (fms) of x, y and z is defined by: 26 fms(x,y,z)= x*y - z 27 Note: this is neither in IEEE 754-2008, nor in LIA-2, but both the 28 PowerPC and the Itanium define fms as x*y - z. 29 */ 30 int 31 mpfr_fms (mpfr_ptr s, mpfr_srcptr x, mpfr_srcptr y, mpfr_srcptr z, 32 mpfr_rnd_t rnd_mode) 33 { 34 mpfr_t minus_z; 35 36 MPFR_ALIAS (minus_z, z, -MPFR_SIGN(z), MPFR_EXP(z)); 37 return mpfr_fma (s, x, y, minus_z, rnd_mode); 38 } 39