libgcc/config/loongarch/crtfastmath.c

   1 /* Copyright (C) 2021-2024 Free Software Foundation, Inc.
   2    Contributed by Loongson Ltd.
   3    Based on MIPS target for GNU compiler.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT
  13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14 or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15 License for more details.
  16
  17 Under Section 7 of GPL version 3, you are granted additional
  18 permissions described in the GCC Runtime Library Exception, version
  19 3.1, as published by the Free Software Foundation.
  20
  21 You should have received a copy of the GNU General Public License
  22 and a copy of the GCC Runtime Library Exception along with this
  23 program; see the files COPYING3 and COPYING.RUNTIME respectively.
  24 If not, see <http://www.gnu.org/licenses/>.  */
  25
  26 #ifdef __loongarch_hard_float
  27
  28 /* Rounding control.  */
  29 #define _FPU_RC_NEAREST 0x000     /* RECOMMENDED.  */
  30 #define _FPU_RC_ZERO    0x100
  31 #define _FPU_RC_UP      0x200
  32 #define _FPU_RC_DOWN    0x300
  33
  34 /* Enable interrupts for IEEE exceptions.  */
  35 #define _FPU_IEEE     0x0000001F
  36
  37 /* Macros for accessing the hardware control word.  */
  38 #define _FPU_GETCW(cw) __asm__ volatile ("movfcsr2gr %0,$r0" : "=r" (cw))
  39 #define _FPU_SETCW(cw) __asm__ volatile ("movgr2fcsr $r0,%0" : : "r" (cw))
  40
  41 static void __attribute__((constructor))
  42 set_fast_math (void)
  43 {
  44   unsigned int fcr;
  45
  46   /* Flush to zero, round to nearest, IEEE exceptions disabled.  */
  47   fcr = _FPU_RC_NEAREST;
  48
  49   _FPU_SETCW (fcr);
  50 }
  51
  52 #endif /* __loongarch_hard_float  */