mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-25 14:30:06 +00:00
53 lines
1.8 KiB
C
53 lines
1.8 KiB
C
/* Initialize CPU feature data via IFUNC relocation.
|
|
Copyright (C) 2015-2021 Free Software Foundation, Inc.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
|
|
#include <ldsodefs.h>
|
|
|
|
#ifdef SHARED
|
|
# include <cpu-features.c>
|
|
|
|
/* NB: Normally, DL_PLATFORM_INIT calls init_cpu_features to initialize
|
|
CPU features in dynamic executable. But when loading ld.so inside of
|
|
static executable, DL_PLATFORM_INIT isn't called and IFUNC relocation
|
|
is used to call init_cpu_features. In static executable, it is called
|
|
once by IFUNC relocation. In dynamic executable, it is called twice
|
|
by DL_PLATFORM_INIT and by IFUNC relocation. */
|
|
extern void __x86_cpu_features (void) attribute_hidden;
|
|
void (*const __x86_cpu_features_p) (void) attribute_hidden
|
|
= __x86_cpu_features;
|
|
|
|
void
|
|
_dl_x86_init_cpu_features (void)
|
|
{
|
|
struct cpu_features *cpu_features = __get_cpu_features ();
|
|
if (cpu_features->basic.kind == arch_kind_unknown)
|
|
init_cpu_features (cpu_features);
|
|
}
|
|
|
|
__ifunc (__x86_cpu_features, __x86_cpu_features, NULL, void,
|
|
_dl_x86_init_cpu_features);
|
|
#endif
|
|
|
|
#undef _dl_x86_get_cpu_features
|
|
|
|
const struct cpu_features *
|
|
_dl_x86_get_cpu_features (void)
|
|
{
|
|
return &GLRO(dl_x86_cpu_features);
|
|
}
|