gdb/arm-wince-tdep.c

   1 /* Target-dependent code for Windows CE running on ARM processors,
   2    for GDB.
   3
   4    Copyright (C) 2007 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "osabi.h"
  23 #include "gdbcore.h"
  24 #include "target.h"
  25
  26 #include "gdb_string.h"
  27
  28 #include "arm-tdep.h"
  29
  30 static const char arm_wince_le_breakpoint[] = { 0x10, 0x00, 0x00, 0xe6 };
  31 static const char arm_wince_thumb_le_breakpoint[] = { 0xfe, 0xdf };
  32
  33 /* Description of the longjmp buffer.  */
  34 #define ARM_WINCE_JB_ELEMENT_SIZE       INT_REGISTER_SIZE
  35 #define ARM_WINCE_JB_PC                 10
  36
  37 static CORE_ADDR
  38 arm_pe_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
  39 {
  40   ULONGEST indirect;
  41   struct minimal_symbol *indsym;
  42   char *symname;
  43   CORE_ADDR next_pc;
  44
  45   /* The format of an ARM DLL trampoline is:
  46        ldr  ip, [pc]
  47        ldr  pc, [ip]
  48        .dw __imp_<func>  */
  49
  50   if (pc == 0
  51       || read_memory_unsigned_integer (pc + 0, 4) != 0xe59fc000
  52       || read_memory_unsigned_integer (pc + 4, 4) != 0xe59cf000)
  53     return 0;
  54
  55   indirect = read_memory_unsigned_integer (pc + 8, 4);
  56   if (indirect == 0)
  57     return 0;
  58
  59   indsym = lookup_minimal_symbol_by_pc (indirect);
  60   if (indsym == NULL)
  61     return 0;
  62
  63   symname = SYMBOL_LINKAGE_NAME (indsym);
  64   if (symname == NULL || strncmp (symname, "__imp_", 6) != 0)
  65     return 0;
  66
  67   next_pc = read_memory_unsigned_integer (indirect, 4);
  68   if (next_pc != 0)
  69     return next_pc;
  70
  71   /* Check with the default arm gdbarch_skip_trampoline.  */
  72   return arm_skip_stub (frame, pc);
  73 }
  74
  75 static void
  76 arm_wince_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  77 {
  78   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  79
  80   tdep->arm_breakpoint = arm_wince_le_breakpoint;
  81   tdep->arm_breakpoint_size = sizeof (arm_wince_le_breakpoint);
  82   tdep->thumb_breakpoint = arm_wince_thumb_le_breakpoint;
  83   tdep->thumb_breakpoint_size = sizeof (arm_wince_thumb_le_breakpoint);
  84   tdep->struct_return = pcc_struct_return;
  85
  86   tdep->fp_model = ARM_FLOAT_SOFT_VFP;
  87
  88   tdep->jb_pc = ARM_WINCE_JB_PC;
  89   tdep->jb_elt_size = ARM_WINCE_JB_ELEMENT_SIZE;
  90
  91   /* On ARM WinCE char defaults to signed.  */
  92   set_gdbarch_char_signed (gdbarch, 1);
  93
  94   /* Shared library handling.  */
  95   set_gdbarch_skip_trampoline_code (gdbarch, arm_pe_skip_trampoline_code);
  96
  97   /* Single stepping.  */
  98   set_gdbarch_software_single_step (gdbarch, arm_software_single_step);
  99 }
 100
 101 static enum gdb_osabi
 102 arm_wince_osabi_sniffer (bfd *abfd)
 103 {
 104   const char *target_name = bfd_get_target (abfd);
 105
 106   if (strcmp (target_name, "pei-arm-wince-little") == 0)
 107     return GDB_OSABI_WINCE;
 108
 109   return GDB_OSABI_UNKNOWN;
 110 }
 111
 112 /* Provide a prototype to silence -Wmissing-prototypes.  */
 113 void _initialize_arm_wince_tdep (void);
 114
 115 void
 116 _initialize_arm_wince_tdep (void)
 117 {
 118   gdbarch_register_osabi_sniffer (bfd_arch_arm, bfd_target_coff_flavour,
 119                                   arm_wince_osabi_sniffer);
 120
 121   gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_WINCE,
 122                           arm_wince_init_abi);
 123 }