1 /* Architecture-specific glibc-hwcaps subdirectories.  x86 version.
2    Copyright (C) 2020-2021 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 #include <dl-hwcaps.h>
20 #include <cpu-features.h>
21 #include <ldsodefs.h>
22 #include <get-isa-level.h>
23 
24 const char _dl_hwcaps_subdirs[] = "x86-64-v4:x86-64-v3:x86-64-v2";
25 enum { subdirs_count = 3 }; /* Number of components in _dl_hwcaps_subdirs.  */
26 
27 uint32_t
_dl_hwcaps_subdirs_active(void)28 _dl_hwcaps_subdirs_active (void)
29 {
30   const struct cpu_features *cpu_features = __get_cpu_features ();
31   unsigned int isa_level = get_isa_level (cpu_features);
32   int active = 0;
33 
34   /* Test in reverse preference order.  */
35 
36   /* x86-64-v2.  */
37   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V2))
38     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
39   ++active;
40 
41   /* x86-64-v3.  */
42   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V3))
43     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
44   ++active;
45 
46   /* x86-64-v4.  */
47   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V4))
48     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
49   ++active;
50 
51   return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
52 }
53