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