libgcc/c++-minimal/guard.c

   1 /* 'libstdc++-v3/libsupc++/guard.cc' for offload devices, until we have
   2    libstdc++-v3/libsupc++ proper.
   3
   4    Copyright (C) 2002-2024 Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 Under Section 7 of GPL version 3, you are granted additional
  19 permissions described in the GCC Runtime Library Exception, version
  20 3.1, as published by the Free Software Foundation.
  21
  22 You should have received a copy of the GNU General Public License and
  23 a copy of the GCC Runtime Library Exception along with this program;
  24 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  25 <http://www.gnu.org/licenses/>.  */
  26
  27 #if defined __AMDGCN__
  28 #elif defined __nvptx__
  29 #else
  30 # error not ported
  31 #endif
  32
  33 #include "../../libstdc++-v3/config/cpu/generic/cxxabi_tweaks.h"
  34
  35 /* Copy'n'paste/edit from 'libstdc++-v3/libsupc++/cxxabi.h'.  */
  36
  37 int
  38 __cxa_guard_acquire(__guard*);
  39
  40 void
  41 __cxa_guard_release(__guard*);
  42
  43 void
  44 __cxa_guard_abort(__guard*);
  45
  46 /* Copy'n'paste/edit from 'libstdc++-v3/libsupc++/guard.cc'.  */
  47
  48 #undef _GLIBCXX_GUARD_TEST_AND_ACQUIRE
  49 #undef _GLIBCXX_GUARD_SET_AND_RELEASE
  50 #define _GLIBCXX_GUARD_SET_AND_RELEASE(G) _GLIBCXX_GUARD_SET (G)
  51
  52 static inline int
  53 init_in_progress_flag(__guard* g)
  54 { return ((char *)g)[1]; }
  55
  56 static inline void
  57 set_init_in_progress_flag(__guard* g, int v)
  58 { ((char *)g)[1] = v; }
  59
  60 static inline void
  61 throw_recursive_init_exception(void)
  62 {
  63   // Use __builtin_trap so we don't require abort().
  64   __builtin_trap();
  65 }
  66
  67 // acquire() is a helper function used to acquire guard if thread support is
  68 // not compiled in or is compiled in but not enabled at run-time.
  69 static int
  70 acquire(__guard *g)
  71 {
  72   // Quit if the object is already initialized.
  73   if (_GLIBCXX_GUARD_TEST(g))
  74     return 0;
  75
  76   if (init_in_progress_flag(g))
  77     throw_recursive_init_exception();
  78
  79   set_init_in_progress_flag(g, 1);
  80   return 1;
  81 }
  82
  83 int __cxa_guard_acquire (__guard *g)
  84 {
  85   return acquire (g);
  86 }
  87
  88 void __cxa_guard_abort (__guard *g)
  89 {
  90   set_init_in_progress_flag(g, 0);
  91 }
  92
  93 void __cxa_guard_release (__guard *g)
  94 {
  95   set_init_in_progress_flag(g, 0);
  96   _GLIBCXX_GUARD_SET_AND_RELEASE (g);
  97 }