gdb/arm-wince-tdep.c

   1 /* Target-dependent code for Windows CE running on ARM processors,
   2    for GDB.
   3
   4    Copyright (C) 2007, 2008 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 #include "solib.h"
  26 #include "solib-target.h"
  27
  28 #include "gdb_string.h"
  29
  30 #include "arm-tdep.h"
  31
  32 static const char arm_wince_le_breakpoint[] = { 0x10, 0x00, 0x00, 0xe6 };
  33 static const char arm_wince_thumb_le_breakpoint[] = { 0xfe, 0xdf };
  34
  35 /* Description of the longjmp buffer.  */
  36 #define ARM_WINCE_JB_ELEMENT_SIZE       INT_REGISTER_SIZE
  37 #define ARM_WINCE_JB_PC                 10
  38
  39 static CORE_ADDR
  40 arm_pe_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
  41 {
  42   ULONGEST indirect;
  43   struct minimal_symbol *indsym;
  44   char *symname;
  45   CORE_ADDR next_pc;
  46
  47   /* The format of an ARM DLL trampoline is:
  48        ldr  ip, [pc]
  49        ldr  pc, [ip]
  50        .dw __imp_<func>  */
  51
  52   if (pc == 0
  53       || read_memory_unsigned_integer (pc + 0, 4) != 0xe59fc000
  54       || read_memory_unsigned_integer (pc + 4, 4) != 0xe59cf000)
  55     return 0;
  56
  57   indirect = read_memory_unsigned_integer (pc + 8, 4);
  58   if (indirect == 0)
  59     return 0;
  60
  61   indsym = lookup_minimal_symbol_by_pc (indirect);
  62   if (indsym == NULL)
  63     return 0;
  64
  65   symname = SYMBOL_LINKAGE_NAME (indsym);
  66   if (symname == NULL || strncmp (symname, "__imp_", 6) != 0)
  67     return 0;
  68
  69   next_pc = read_memory_unsigned_integer (indirect, 4);
  70   if (next_pc != 0)
  71     return next_pc;
  72
  73   /* Check with the default arm gdbarch_skip_trampoline.  */
  74   return arm_skip_stub (frame, pc);
  75 }
  76
  77 static void
  78 arm_wince_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  79 {
  80   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  81
  82   tdep->arm_breakpoint = arm_wince_le_breakpoint;
  83   tdep->arm_breakpoint_size = sizeof (arm_wince_le_breakpoint);
  84   tdep->thumb_breakpoint = arm_wince_thumb_le_breakpoint;
  85   tdep->thumb_breakpoint_size = sizeof (arm_wince_thumb_le_breakpoint);
  86   tdep->struct_return = pcc_struct_return;
  87
  88   tdep->fp_model = ARM_FLOAT_SOFT_VFP;
  89
  90   tdep->jb_pc = ARM_WINCE_JB_PC;
  91   tdep->jb_elt_size = ARM_WINCE_JB_ELEMENT_SIZE;
  92
  93   /* On ARM WinCE char defaults to signed.  */
  94   set_gdbarch_char_signed (gdbarch, 1);
  95
  96   /* Shared library handling.  */
  97   set_solib_ops (gdbarch, &solib_target_so_ops);
  98   set_gdbarch_skip_trampoline_code (gdbarch, arm_pe_skip_trampoline_code);
  99
 100   /* Single stepping.  */
 101   set_gdbarch_software_single_step (gdbarch, arm_software_single_step);
 102 }
 103
 104 static enum gdb_osabi
 105 arm_wince_osabi_sniffer (bfd *abfd)
 106 {
 107   const char *target_name = bfd_get_target (abfd);
 108
 109   if (strcmp (target_name, "pei-arm-wince-little") == 0)
 110     return GDB_OSABI_WINCE;
 111
 112   return GDB_OSABI_UNKNOWN;
 113 }
 114
 115 /* Provide a prototype to silence -Wmissing-prototypes.  */
 116 void _initialize_arm_wince_tdep (void);
 117
 118 void
 119 _initialize_arm_wince_tdep (void)
 120 {
 121   gdbarch_register_osabi_sniffer (bfd_arch_arm, bfd_target_coff_flavour,
 122                                   arm_wince_osabi_sniffer);
 123
 124   gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_WINCE,
 125                           arm_wince_init_abi);
 126 }