lib/fenv-except-tracking-test.c

   1 /* Functions for tracking which floating-point exceptions have occurred.
   2    Copyright (C) 1997-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Based on glibc/sysdeps/<cpu>/{fclrexcpt.c,fraiseexcpt.c,ftestexcept.c}
  18    together with glibc/sysdeps/<cpu>/{fpu_control.h,fenv_private.h,fenv_libc.h}.  */
  19
  20 #include <config.h>
  21
  22 /* Specification.  */
  23 #include <fenv.h>
  24
  25 #include "fenv-private.h"
  26
  27 #if defined _AIX && defined __powerpc__ /* AIX */
  28
  29 /* On AIX, the register fpscr is augmented with a 32-bit word named fpscrx
  30    in thread-local storage.  Instead of accessing fpscr, we must access the
  31    combination.  The function fp_read_flag() does this.  */
  32
  33 # include <float.h>
  34 # include <fpxcp.h>
  35
  36 /* Documentation:
  37    <https://www.ibm.com/docs/en/aix/7.3?topic=f-fp-clr-flag-fp-set-flag-fp-read-flag-fp-swap-flag-subroutine>  */
  38
  39 int
  40 fetestexcept (int exceptions)
  41 {
  42   fpflag_t flags = fp_read_flag ();
  43   return fpflag_to_exceptions (flags) & FE_ALL_EXCEPT & exceptions;
  44 }
  45
  46 #elif defined __GNUC__ || defined __clang__ || defined _MSC_VER
  47
  48 # if (defined __x86_64__ || defined _M_X64) || (defined __i386 || defined _M_IX86)
  49
  50 int
  51 fetestexcept (int exceptions)
  52 {
  53 #  if defined _MSC_VER
  54
  55   /* Look at the flags in the SSE unit.  */
  56   unsigned int mxcsr;
  57   _FPU_GETSSECW (mxcsr);
  58   return x86hardware_to_exceptions (mxcsr) & FE_ALL_EXCEPT & exceptions;
  59
  60 #  else
  61
  62   unsigned short fstat;
  63   _FPU_GETSTAT (fstat);
  64
  65   unsigned int mxcsr = 0;
  66   if (CPU_HAS_SSE ())
  67     {
  68       /* Look at the flags in the SSE unit as well.  */
  69       _FPU_GETSSECW (mxcsr);
  70     }
  71
  72   return x86hardware_to_exceptions (fstat | mxcsr) & FE_ALL_EXCEPT & exceptions;
  73 #  endif
  74 }
  75
  76 # elif defined __aarch64__ /* arm64 */
  77
  78 int
  79 fetestexcept (int exceptions)
  80 {
  81   unsigned long fpsr;
  82   _FPU_GETFPSR (fpsr);
  83   return fpsr & FE_ALL_EXCEPT & exceptions;
  84 }
  85
  86 # elif defined __arm__
  87
  88 int
  89 fetestexcept (int exceptions)
  90 {
  91 #  ifdef __SOFTFP__
  92   return 0;
  93 #  else
  94   unsigned int fpscr;
  95   _FPU_GETCW (fpscr);
  96   return fpscr & FE_ALL_EXCEPT & exceptions;
  97 #  endif
  98 }
  99
 100 # elif defined __alpha
 101
 102 int
 103 fetestexcept (int exceptions)
 104 {
 105   unsigned long swcr = __ieee_get_fp_control ();
 106   return swcr & FE_ALL_EXCEPT & exceptions;
 107 }
 108
 109 # elif defined __hppa
 110
 111 int
 112 fetestexcept (int exceptions)
 113 {
 114   union { unsigned long long fpreg; unsigned int halfreg[2]; } s;
 115   /* Get the current status word. */
 116   __asm__ __volatile__ ("fstd %%fr0,0(%1)" : "=m" (s.fpreg) : "r" (&s.fpreg) : "%r0");
 117   return (s.halfreg[0] >> 27) & FE_ALL_EXCEPT & exceptions;
 118 }
 119
 120 # elif defined __ia64__
 121
 122 int
 123 fetestexcept (int exceptions)
 124 {
 125   unsigned long fpsr;
 126   _FPU_GETCW (fpsr);
 127   return (fpsr >> 13) & FE_ALL_EXCEPT & exceptions;
 128 }
 129
 130 # elif defined __m68k__
 131
 132 int
 133 fetestexcept (int exceptions)
 134 {
 135   unsigned int fpsr;
 136   _FPU_GETFPSR (fpsr);
 137   return fpsr & FE_ALL_EXCEPT & exceptions;
 138 }
 139
 140 # elif defined __mips__
 141
 142 int
 143 fetestexcept (int exceptions)
 144 {
 145   unsigned int fcsr;
 146   _FPU_GETCW (fcsr);
 147   return fcsr & FE_ALL_EXCEPT & exceptions;
 148 }
 149
 150 # elif defined __loongarch__
 151
 152 int
 153 fetestexcept (int exceptions)
 154 {
 155   unsigned int fcsr;
 156   _FPU_GETCW (fcsr);
 157   return fcsr & FE_ALL_EXCEPT & exceptions;
 158 }
 159
 160 # elif defined __powerpc__
 161
 162 int
 163 fetestexcept (int exceptions)
 164 {
 165   union { unsigned long long u; double f; } memenv;
 166   _FPU_GETCW_AS_DOUBLE (memenv.f);
 167   return memenv.u & FE_ALL_EXCEPT & exceptions;
 168 }
 169
 170 # elif defined __riscv
 171
 172 int
 173 fetestexcept (int exceptions)
 174 {
 175   unsigned int flags;
 176   __asm__ __volatile__ ("frflags %0" : "=r" (flags)); /* same as "csrr %0, fflags" */
 177   return flags & FE_ALL_EXCEPT & exceptions;
 178 }
 179
 180 # elif defined __s390__ || defined __s390x__
 181
 182 int
 183 fetestexcept (int exceptions)
 184 {
 185   unsigned int fpc;
 186   _FPU_GETCW (fpc);
 187 #  if FE_INEXACT == 8 /* glibc compatible FE_* values */
 188   return ((fpc >> 16) | ((fpc & 0x00000300) == 0 ? fpc >> 8 : 0))
 189          & FE_ALL_EXCEPT & exceptions;
 190 #  else /* musl libc compatible FE_* values */
 191   return (fpc | ((fpc & 0x00000300) == 0 ? fpc << 8 : 0))
 192          & FE_ALL_EXCEPT & exceptions;
 193 #  endif
 194 }
 195
 196 # elif defined __sh__
 197
 198 int
 199 fetestexcept (int exceptions)
 200 {
 201   unsigned int fpscr;
 202   _FPU_GETCW (fpscr);
 203   return fpscr & FE_ALL_EXCEPT & exceptions;
 204 }
 205
 206 # elif defined __sparc
 207
 208 int
 209 fetestexcept (int exceptions)
 210 {
 211   unsigned long fsr;
 212   _FPU_GETCW (fsr);
 213 #  if FE_INEXACT == 32 /* glibc compatible FE_* values */
 214   return fsr & FE_ALL_EXCEPT & exceptions;
 215 #  else /* Solaris compatible FE_* values */
 216   return (fsr >> 5) & FE_ALL_EXCEPT & exceptions;
 217 #  endif
 218 }
 219
 220 # else
 221
 222 #  if defined __GNUC__ || defined __clang__
 223 #   warning "Unknown CPU / architecture. Please report your platform and compiler to <bug-gnulib@gnu.org>."
 224 #  endif
 225 #  define NEED_FALLBACK 1
 226
 227 # endif
 228
 229 #else
 230
 231 /* The compiler does not support __asm__ statements or equivalent
 232    intrinsics.  */
 233
 234 # if HAVE_FPSETSTICKY
 235 /* FreeBSD ≥ 3.1, NetBSD ≥ 1.1, OpenBSD, IRIX, Solaris, Minix ≥ 3.2.  */
 236
 237 /* Get fpgetsticky, fpsetsticky.  */
 238 #  include <ieeefp.h>
 239 /* The type is called 'fp_except_t' on FreeBSD, but 'fp_except' on
 240    all other systems.  */
 241 #  if !defined __FreeBSD__
 242 #   define fp_except_t fp_except
 243 #  endif
 244
 245 int
 246 fetestexcept (int exceptions)
 247 {
 248   fp_except_t flags = fpgetsticky ();
 249   return flags & FE_ALL_EXCEPT & exceptions;
 250 }
 251
 252 # else
 253
 254 #  define NEED_FALLBACK 1
 255
 256 # endif
 257
 258 #endif
 259
 260 #if NEED_FALLBACK
 261
 262 /* A dummy fallback.  */
 263
 264 int
 265 fetestexcept (int exceptions)
 266 {
 267   return 0;
 268 }
 269
 270 #endif