sysdeps/x86/fpu/test-fenv-sse.c

   1 /* Test floating-point environment includes SSE state (bug 16064).
   2    Copyright (C) 2014-2018 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <cpuid.h>
  20 #include <fenv.h>
  21 #include <float.h>
  22 #include <stdbool.h>
  23 #include <stdio.h>
  24
  25 static bool
  26 have_sse2 (void)
  27 {
  28   unsigned int eax, ebx, ecx, edx;
  29
  30   if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx))
  31     return false;
  32
  33   return (edx & bit_SSE2) != 0;
  34 }
  35
  36 static __attribute__ ((noinline)) int
  37 sse_tests (void)
  38 {
  39   int ret = 0;
  40   fenv_t base_env;
  41   if (fegetenv (&base_env) != 0)
  42     {
  43       puts ("fegetenv (&base_env) failed");
  44       return 1;
  45     }
  46   if (fesetround (FE_UPWARD) != 0)
  47     {
  48       puts ("fesetround (FE_UPWARD) failed");
  49       return 1;
  50     }
  51   if (fesetenv (&base_env) != 0)
  52     {
  53       puts ("fesetenv (&base_env) failed");
  54       return 1;
  55     }
  56   volatile float a = 1.0f, b = FLT_MIN, c;
  57   c = a + b;
  58   if (c != 1.0f)
  59     {
  60       puts ("fesetenv did not restore rounding mode");
  61       ret = 1;
  62     }
  63   if (fesetround (FE_DOWNWARD) != 0)
  64     {
  65       puts ("fesetround (FE_DOWNWARD) failed");
  66       return 1;
  67     }
  68   if (feupdateenv (&base_env) != 0)
  69     {
  70       puts ("feupdateenv (&base_env) failed");
  71       return 1;
  72     }
  73   volatile float d = -FLT_MIN, e;
  74   e = a + d;
  75   if (e != 1.0f)
  76     {
  77       puts ("feupdateenv did not restore rounding mode");
  78       ret = 1;
  79     }
  80   if (fesetround (FE_UPWARD) != 0)
  81     {
  82       puts ("fesetround (FE_UPWARD) failed");
  83       return 1;
  84     }
  85   fenv_t upward_env;
  86   if (feholdexcept (&upward_env) != 0)
  87     {
  88       puts ("feholdexcept (&upward_env) failed");
  89       return 1;
  90     }
  91   if (fesetround (FE_DOWNWARD) != 0)
  92     {
  93       puts ("fesetround (FE_DOWNWARD) failed");
  94       return 1;
  95     }
  96   if (fesetenv (&upward_env) != 0)
  97     {
  98       puts ("fesetenv (&upward_env) failed");
  99       return 1;
 100     }
 101   e = a + d;
 102   if (e != 1.0f)
 103     {
 104       puts ("fesetenv did not restore rounding mode from feholdexcept");
 105       ret = 1;
 106     }
 107   if (fesetround (FE_UPWARD) != 0)
 108     {
 109       puts ("fesetround (FE_UPWARD) failed");
 110       return 1;
 111     }
 112   if (fesetenv (FE_DFL_ENV) != 0)
 113     {
 114       puts ("fesetenv (FE_DFL_ENV) failed");
 115       return 1;
 116     }
 117   c = a + b;
 118   if (c != 1.0f)
 119     {
 120       puts ("fesetenv (FE_DFL_ENV) did not restore rounding mode");
 121       ret = 1;
 122     }
 123   return ret;
 124 }
 125
 126 static int
 127 do_test (void)
 128 {
 129   if (!have_sse2 ())
 130     {
 131       puts ("CPU does not support SSE2, cannot test");
 132       return 0;
 133     }
 134   return sse_tests ();
 135 }
 136
 137 #define TEST_FUNCTION do_test ()
 138 #include <test-skeleton.c>