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) 2017-2023 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;