1 /* Define INIT_ARCH so that midr is initialized before use by IFUNCs.
2    This file is part of the GNU C Library.
3    Copyright (C) 2017-2022 Free Software Foundation, Inc.
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 <ldsodefs.h>
20 #include <sys/auxv.h>
21 
22 /* Make glibc MTE-safe on a system that supports MTE in case user code
23    enables tag checks independently of the mte_status of glibc.  There
24    is currently no ABI contract for enabling tag checks in user code,
25    but this can be useful for debugging with MTE.  */
26 #define MTE_ENABLED() (GLRO(dl_hwcap2) & HWCAP2_MTE)
27 
28 #define INIT_ARCH()							      \
29   uint64_t __attribute__((unused)) midr =				      \
30     GLRO(dl_aarch64_cpu_features).midr_el1;				      \
31   unsigned __attribute__((unused)) zva_size =				      \
32     GLRO(dl_aarch64_cpu_features).zva_size;				      \
33   bool __attribute__((unused)) bti =					      \
34     HAVE_AARCH64_BTI && GLRO(dl_aarch64_cpu_features).bti;		      \
35   bool __attribute__((unused)) mte =					      \
36     MTE_ENABLED ();							      \
37   bool __attribute__((unused)) sve =					      \
38     GLRO(dl_aarch64_cpu_features).sve;
39