gdb/testsuite/gdb.arch/aarch64-tagged-pointer.c

   1 /* This file is part of GDB, the GNU debugger.
   2
   3    Copyright 2017 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include <stdint.h>
  19
  20 struct s
  21 {
  22   int i;
  23 };
  24
  25 static void
  26 foo (void)
  27 {
  28 }
  29
  30 int
  31 main (void)
  32 {
  33   struct s s1;
  34   struct s *sp1, *sp2;
  35   int i = 1234;
  36   int *p1, *p2;
  37
  38   s1.i = 1234;
  39   sp1 = &s1;
  40   p1 = &i;
  41   /* SP1 and SP2 have different tags, but point to the same address.  */
  42   sp2 = (struct s *) ((uintptr_t) sp1 | 0xf000000000000000ULL);
  43   p2 = (int *) ((uintptr_t) p1 | 0xf000000000000000ULL);
  44
  45   void (*func_ptr) (void) = foo;
  46   func_ptr = (void (*) (void)) ((uintptr_t) func_ptr | 0xf000000000000000ULL);
  47   sp2->i = 4321; /* breakpoint here.  */
  48
  49   for (int i = 0; i < 2; i++)
  50     {
  51       foo ();
  52       (*func_ptr) ();
  53     }
  54
  55   sp1->i = 8765;
  56   i = 1;
  57 }