gdb/testsuite/gdb.base/watchpoint-unaligned.c

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 2017-2024 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 #include <assert.h>
  20
  21 static int again;
  22
  23 static volatile struct
  24 {
  25   uint64_t alignment;
  26   union
  27     {
  28       uint64_t size8[1];
  29       uint32_t size4[2];
  30       uint16_t size2[4];
  31       uint8_t size1[8];
  32       uint64_t size8twice[3];
  33     }
  34   u;
  35 } data;
  36
  37 static int size = 0;
  38 static int offset;
  39
  40 static void
  41 write_size8twice (void)
  42 {
  43   static const uint64_t first = 1;
  44   static const uint64_t second = 2;
  45
  46 #ifdef __aarch64__
  47   volatile void *p = &data.u.size8twice[offset];
  48   asm volatile ("stp %1, %2, [%0]"
  49                 : /* output */
  50                 : "r" (p), "r" (first), "r" (second) /* input */
  51                 : "memory" /* clobber */);
  52 #else
  53   data.u.size8twice[offset] = first;
  54   data.u.size8twice[offset + 1] = second;
  55 #endif
  56 }
  57
  58 int
  59 main (void)
  60 {
  61   volatile uint64_t local;
  62
  63   assert (sizeof (data) == 8 + 3 * 8);
  64
  65   write_size8twice ();
  66
  67   while (size)
  68     {
  69       switch (size)
  70         {
  71 /* __s390x__ also defines __s390__ */
  72 #ifdef __s390__
  73 # define ACCESS(var) var = ~var
  74 #else
  75 # define ACCESS(var) local = var
  76 #endif
  77         case 8:
  78           ACCESS (data.u.size8[offset]);
  79           break;
  80         case 4:
  81           ACCESS (data.u.size4[offset]);
  82           break;
  83         case 2:
  84           ACCESS (data.u.size2[offset]);
  85           break;
  86         case 1:
  87           ACCESS (data.u.size1[offset]);
  88           break;
  89 #undef ACCESS
  90         default:
  91           assert (0);
  92         }
  93       size = 0;
  94       size = size; /* start_again */
  95     }
  96   return 0; /* final_return */
  97 }