gdb/armobsd-tdep.c

   1 /* Target-dependent code for OpenBSD/arm.
   2
   3    Copyright (C) 2006 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include "defs.h"
  23 #include "osabi.h"
  24 #include "trad-frame.h"
  25 #include "tramp-frame.h"
  26
  27 #include "obsd-tdep.h"
  28 #include "arm-tdep.h"
  29 #include "solib-svr4.h"
  30
  31 /* Signal trampolines.  */
  32
  33 static void
  34 armobsd_sigframe_init (const struct tramp_frame *self,
  35                        struct frame_info *next_frame,
  36                        struct trad_frame_cache *cache,
  37                        CORE_ADDR func)
  38 {
  39   CORE_ADDR sp, sigcontext_addr, addr;
  40   int regnum;
  41
  42   /* We find the appropriate instance of `struct sigcontext' at a
  43      fixed offset in the signal frame.  */
  44   sp = frame_unwind_register_signed (next_frame, ARM_SP_REGNUM);
  45   sigcontext_addr = sp + 16;
  46
  47   /* PC.  */
  48   trad_frame_set_reg_addr (cache, ARM_PC_REGNUM, sigcontext_addr + 76);
  49
  50   /* GPRs.  */
  51   for (regnum = ARM_A1_REGNUM, addr = sigcontext_addr + 12;
  52        regnum <= ARM_LR_REGNUM; regnum++, addr += 4)
  53     trad_frame_set_reg_addr (cache, regnum, addr);
  54
  55   trad_frame_set_id (cache, frame_id_build (sp, func));
  56 }
  57
  58 static const struct tramp_frame armobsd_sigframe =
  59 {
  60   SIGTRAMP_FRAME,
  61   4,
  62   {
  63     { 0xe28d0010, -1 },         /* add     r0, sp, #16 */
  64     { 0xef000067, -1 },         /* swi     SYS_sigreturn */
  65     { 0xef000001, -1 },         /* swi     SYS_exit */
  66     { 0xeafffffc, -1 },         /* b       . - 8 */
  67     { TRAMP_SENTINEL_INSN, -1 }
  68   },
  69   armobsd_sigframe_init
  70 };
  71 \f
  72
  73 static void
  74 armobsd_init_abi (struct gdbarch_info info,
  75                   struct gdbarch *gdbarch)
  76 {
  77   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  78
  79   if (tdep->fp_model == ARM_FLOAT_AUTO)
  80     tdep->fp_model = ARM_FLOAT_SOFT_VFP;
  81
  82   tramp_frame_prepend_unwinder (gdbarch, &armobsd_sigframe);
  83
  84   /* OpenBSD/arm uses SVR4-style shared libraries.  */
  85   set_solib_svr4_fetch_link_map_offsets
  86     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
  87   set_gdbarch_skip_solib_resolver (gdbarch, obsd_skip_solib_resolver);
  88
  89   tdep->jb_pc = 24;
  90   tdep->jb_elt_size = 4;
  91 }
  92
  93 void
  94 _initialize_armobsd_tdep (void)
  95 {
  96   gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_OPENBSD_ELF,
  97                           armobsd_init_abi);
  98 }