| /* Target-dependent code for Windows CE running on ARM processors, |
| for GDB. |
| |
| Copyright (C) 2007-2012 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "defs.h" |
| #include "osabi.h" |
| #include "gdbcore.h" |
| #include "target.h" |
| #include "solib.h" |
| #include "solib-target.h" |
| #include "frame.h" |
| |
| #include "gdb_string.h" |
| |
| #include "arm-tdep.h" |
| |
| static const char arm_wince_le_breakpoint[] = { 0x10, 0x00, 0x00, 0xe6 }; |
| static const char arm_wince_thumb_le_breakpoint[] = { 0xfe, 0xdf }; |
| |
| /* Description of the longjmp buffer. */ |
| #define ARM_WINCE_JB_ELEMENT_SIZE INT_REGISTER_SIZE |
| #define ARM_WINCE_JB_PC 10 |
| |
| static CORE_ADDR |
| arm_pe_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (frame); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| ULONGEST indirect; |
| struct minimal_symbol *indsym; |
| const char *symname; |
| CORE_ADDR next_pc; |
| |
| /* The format of an ARM DLL trampoline is: |
| ldr ip, [pc] |
| ldr pc, [ip] |
| .dw __imp_<func> */ |
| |
| if (pc == 0 |
| || read_memory_unsigned_integer (pc + 0, 4, byte_order) != 0xe59fc000 |
| || read_memory_unsigned_integer (pc + 4, 4, byte_order) != 0xe59cf000) |
| return 0; |
| |
| indirect = read_memory_unsigned_integer (pc + 8, 4, byte_order); |
| if (indirect == 0) |
| return 0; |
| |
| indsym = lookup_minimal_symbol_by_pc (indirect); |
| if (indsym == NULL) |
| return 0; |
| |
| symname = SYMBOL_LINKAGE_NAME (indsym); |
| if (symname == NULL || strncmp (symname, "__imp_", 6) != 0) |
| return 0; |
| |
| next_pc = read_memory_unsigned_integer (indirect, 4, byte_order); |
| if (next_pc != 0) |
| return next_pc; |
| |
| /* Check with the default arm gdbarch_skip_trampoline. */ |
| return arm_skip_stub (frame, pc); |
| } |
| |
| /* GCC emits a call to __gccmain in the prologue of main. |
| |
| The function below examines the code pointed at by PC and checks to |
| see if it corresponds to a call to __gccmain. If so, it returns |
| the address of the instruction following that call. Otherwise, it |
| simply returns PC. */ |
| |
| static CORE_ADDR |
| arm_wince_skip_main_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| { |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| ULONGEST this_instr; |
| |
| this_instr = read_memory_unsigned_integer (pc, 4, byte_order); |
| |
| /* bl offset <__gccmain> */ |
| if ((this_instr & 0xfff00000) == 0xeb000000) |
| { |
| #define sign_extend(V, N) \ |
| (((long) (V) ^ (1L << ((N) - 1))) - (1L << ((N) - 1))) |
| |
| long offset = sign_extend (this_instr & 0x000fffff, 23) << 2; |
| CORE_ADDR call_dest = (pc + 8 + offset) & 0xffffffffU; |
| struct minimal_symbol *s = lookup_minimal_symbol_by_pc (call_dest); |
| |
| if (s != NULL |
| && SYMBOL_LINKAGE_NAME (s) != NULL |
| && strcmp (SYMBOL_LINKAGE_NAME (s), "__gccmain") == 0) |
| pc += 4; |
| } |
| |
| return pc; |
| } |
| |
| static void |
| arm_wince_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| tdep->arm_breakpoint = arm_wince_le_breakpoint; |
| tdep->arm_breakpoint_size = sizeof (arm_wince_le_breakpoint); |
| tdep->thumb_breakpoint = arm_wince_thumb_le_breakpoint; |
| tdep->thumb_breakpoint_size = sizeof (arm_wince_thumb_le_breakpoint); |
| tdep->struct_return = pcc_struct_return; |
| |
| tdep->fp_model = ARM_FLOAT_SOFT_VFP; |
| |
| tdep->jb_pc = ARM_WINCE_JB_PC; |
| tdep->jb_elt_size = ARM_WINCE_JB_ELEMENT_SIZE; |
| |
| /* On ARM WinCE char defaults to signed. */ |
| set_gdbarch_char_signed (gdbarch, 1); |
| |
| /* Shared library handling. */ |
| set_solib_ops (gdbarch, &solib_target_so_ops); |
| set_gdbarch_skip_trampoline_code (gdbarch, arm_pe_skip_trampoline_code); |
| |
| /* Single stepping. */ |
| set_gdbarch_software_single_step (gdbarch, arm_software_single_step); |
| |
| /* Skip call to __gccmain that gcc places in main. */ |
| set_gdbarch_skip_main_prologue (gdbarch, arm_wince_skip_main_prologue); |
| |
| /* Canonical paths on this target look like `\Windows\coredll.dll', |
| for example. */ |
| set_gdbarch_has_dos_based_file_system (gdbarch, 1); |
| } |
| |
| static enum gdb_osabi |
| arm_wince_osabi_sniffer (bfd *abfd) |
| { |
| const char *target_name = bfd_get_target (abfd); |
| |
| if (strcmp (target_name, "pei-arm-wince-little") == 0) |
| return GDB_OSABI_WINCE; |
| |
| return GDB_OSABI_UNKNOWN; |
| } |
| |
| /* Provide a prototype to silence -Wmissing-prototypes. */ |
| void _initialize_arm_wince_tdep (void); |
| |
| void |
| _initialize_arm_wince_tdep (void) |
| { |
| gdbarch_register_osabi_sniffer (bfd_arch_arm, bfd_target_coff_flavour, |
| arm_wince_osabi_sniffer); |
| |
| gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_WINCE, |
| arm_wince_init_abi); |
| } |