sysdeps/riscv/fpu_control.h

   1 /* FPU control word bits.  RISC-V version.
   2    Copyright (C) 1996-2023 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 #ifndef _FPU_CONTROL_H
  20 #define _FPU_CONTROL_H
  21
  22 #include <features.h>
  23
  24 #ifndef __riscv_flen
  25
  26 # define _FPU_RESERVED 0xffffffff
  27 # define _FPU_DEFAULT  0x00000000
  28 typedef unsigned int fpu_control_t;
  29 # define _FPU_GETCW(cw) (cw) = 0
  30 # define _FPU_SETCW(cw) do { } while (0)
  31 extern fpu_control_t __fpu_control;
  32
  33 #else /* __riscv_flen */
  34
  35 # define _FPU_RESERVED 0
  36 # define _FPU_DEFAULT  0
  37 # define _FPU_IEEE     _FPU_DEFAULT
  38
  39 /* Type of the control word.  */
  40 typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
  41
  42 /* Macros for accessing the hardware control word.  */
  43 # define _FPU_GETCW(cw) __asm__ volatile ("frsr %0" : "=r" (cw))
  44 # define _FPU_SETCW(cw) __asm__ volatile ("fssr %z0" : : "rJ" (cw))
  45
  46 /* Default control word set at startup.  */
  47 extern fpu_control_t __fpu_control;
  48
  49 # define _FCLASS(x) (__extension__ ({ int __res; \
  50   if (sizeof (x) * 8 > __riscv_flen) __builtin_trap (); \
  51   if (sizeof (x) == 4) asm ("fclass.s %0, %1" : "=r" (__res) : "f" (x)); \
  52   else if (sizeof (x) == 8) asm ("fclass.d %0, %1" : "=r" (__res) : "f" (x)); \
  53   else __builtin_trap (); \
  54   __res; }))
  55
  56 # define _FCLASS_MINF     (1 << 0)
  57 # define _FCLASS_MNORM    (1 << 1)
  58 # define _FCLASS_MSUBNORM (1 << 2)
  59 # define _FCLASS_MZERO    (1 << 3)
  60 # define _FCLASS_PZERO    (1 << 4)
  61 # define _FCLASS_PSUBNORM (1 << 5)
  62 # define _FCLASS_PNORM    (1 << 6)
  63 # define _FCLASS_PINF     (1 << 7)
  64 # define _FCLASS_SNAN     (1 << 8)
  65 # define _FCLASS_QNAN     (1 << 9)
  66 # define _FCLASS_ZERO     (_FCLASS_MZERO | _FCLASS_PZERO)
  67 # define _FCLASS_SUBNORM  (_FCLASS_MSUBNORM | _FCLASS_PSUBNORM)
  68 # define _FCLASS_NORM     (_FCLASS_MNORM | _FCLASS_PNORM)
  69 # define _FCLASS_INF      (_FCLASS_MINF | _FCLASS_PINF)
  70 # define _FCLASS_NAN      (_FCLASS_SNAN | _FCLASS_QNAN)
  71
  72 #endif /* __riscv_flen */
  73
  74 #endif  /* fpu_control.h */