gdb/i386-windows-tdep.c

   1 /* Target-dependent code for Windows (including Cygwin) running on i386's,
   2    for GDB.
   3
   4    Copyright (C) 2003-2024 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 "osabi.h"
  22 #include "i386-tdep.h"
  23 #include "windows-tdep.h"
  24 #include "regset.h"
  25 #include "gdbsupport/gdb_obstack.h"
  26 #include "xml-support.h"
  27 #include "gdbcore.h"
  28 #include "inferior.h"
  29 #include "frame-unwind.h"
  30
  31 /* Core file support.  */
  32
  33 /* This vector maps GDB's idea of a register's number into an address
  34    in the windows exception context vector.  */
  35
  36 static int i386_windows_gregset_reg_offset[] =
  37 {
  38   176, /* eax */
  39   172, /* ecx */
  40   168, /* edx */
  41   164, /* ebx */
  42
  43   196, /* esp */
  44   180, /* ebp */
  45   160, /* esi */
  46   156, /* edi */
  47
  48   184, /* eip */
  49   192, /* eflags */
  50   188, /* cs */
  51   200, /* ss */
  52
  53   152, /* ds */
  54   148, /* es */
  55   144, /* fs */
  56   140, /* gs */
  57
  58   56, /* FloatSave.RegisterArea[0 * 10] */
  59   66, /* FloatSave.RegisterArea[1 * 10] */
  60   76, /* FloatSave.RegisterArea[2 * 10] */
  61   86, /* FloatSave.RegisterArea[3 * 10] */
  62   96, /* FloatSave.RegisterArea[4 * 10] */
  63   106, /* FloatSave.RegisterArea[5 * 10] */
  64   116, /* FloatSave.RegisterArea[6 * 10] */
  65   126, /* FloatSave.RegisterArea[7 * 10] */
  66
  67   28, /* FloatSave.ControlWord */
  68   32, /* FloatSave.StatusWord */
  69   36, /* FloatSave.TagWord */
  70   44, /* FloatSave.ErrorSelector */
  71   40, /* FloatSave.ErrorOffset */
  72   52, /* FloatSave.DataSelector */
  73   48, /* FloatSave.DataOffset */
  74   44, /* FloatSave.ErrorSelector */
  75
  76   /* XMM0-7 */
  77   364, /* ExtendedRegisters[10*16] */
  78   380, /* ExtendedRegisters[11*16] */
  79   396, /* ExtendedRegisters[12*16] */
  80   412, /* ExtendedRegisters[13*16] */
  81   428, /* ExtendedRegisters[14*16] */
  82   444, /* ExtendedRegisters[15*16] */
  83   460, /* ExtendedRegisters[16*16] */
  84   476, /* ExtendedRegisters[17*16] */
  85
  86   /* MXCSR */
  87   228 /* ExtendedRegisters[24] */
  88 };
  89
  90 #define I386_WINDOWS_SIZEOF_GREGSET 716
  91
  92 static CORE_ADDR
  93 i386_windows_skip_trampoline_code (const frame_info_ptr &frame, CORE_ADDR pc)
  94 {
  95   return i386_pe_skip_trampoline_code (frame, pc, NULL);
  96 }
  97
  98 static const char *
  99 i386_windows_auto_wide_charset (void)
 100 {
 101   return "UTF-16";
 102 }
 103
 104 /* Implement the "push_dummy_call" gdbarch method.  */
 105
 106 static CORE_ADDR
 107 i386_windows_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
 108                               struct regcache *regcache, CORE_ADDR bp_addr,
 109                               int nargs, struct value **args, CORE_ADDR sp,
 110                               function_call_return_method return_method,
 111                               CORE_ADDR struct_addr)
 112 {
 113   /* For non-static member functions of 32bit Windows programs, the thiscall
 114      calling convention is used, so the 'this' pointer is passed in ECX.  */
 115   bool thiscall = false;
 116
 117   struct type *type = check_typedef (function->type ());
 118   if (type->code () == TYPE_CODE_PTR)
 119     type = check_typedef (type->target_type ());
 120
 121   /* read_subroutine_type sets for non-static member functions the
 122      artificial flag of the first parameter ('this' pointer).  */
 123   if (type->code () == TYPE_CODE_METHOD
 124       && type->num_fields () > 0
 125       && type->field (0).is_artificial ()
 126       && type->field (0).type ()->code () == TYPE_CODE_PTR)
 127     thiscall = 1;
 128
 129   return i386_thiscall_push_dummy_call (gdbarch, function, regcache, bp_addr,
 130                                         nargs, args, sp, return_method,
 131                                         struct_addr, thiscall);
 132 }
 133
 134 /* Common parts for gdbarch initialization for Windows and Cygwin on i386.  */
 135
 136 static void
 137 i386_windows_init_abi_common (struct gdbarch_info info, struct gdbarch *gdbarch)
 138 {
 139   i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch);
 140
 141   set_gdbarch_skip_trampoline_code (gdbarch, i386_windows_skip_trampoline_code);
 142
 143   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 144
 145   tdep->struct_return = reg_struct_return;
 146
 147   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 148   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 149   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 150
 151   tdep->sizeof_fpregset = 0;
 152
 153   /* Core file support.  */
 154   set_gdbarch_core_xfer_shared_libraries
 155     (gdbarch, windows_core_xfer_shared_libraries);
 156   set_gdbarch_core_pid_to_str (gdbarch, windows_core_pid_to_str);
 157
 158   set_gdbarch_auto_wide_charset (gdbarch, i386_windows_auto_wide_charset);
 159 }
 160
 161 /* gdbarch initialization for Windows on i386.  */
 162
 163 static void
 164 i386_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 165 {
 166   i386_windows_init_abi_common (info, gdbarch);
 167   windows_init_abi (info, gdbarch);
 168
 169   set_gdbarch_push_dummy_call (gdbarch, i386_windows_push_dummy_call);
 170 }
 171
 172 /* Sigwrapper unwinder instruction patterns for i386.  */
 173
 174 static const gdb_byte i386_sigbe_bytes[] = {
 175   0xb8, 0xfc, 0xff, 0xff, 0xff,                 /* movl $-4,%eax */
 176   0x0f, 0xc1, 0x83,                             /* xadd %eax,$tls::stackptr(%ebx) */
 177   /* 4 bytes for tls::stackptr operand.  */
 178 };
 179
 180 static const gdb::array_view<const gdb_byte> i386_sig_patterns[] {
 181   { i386_sigbe_bytes },
 182 };
 183
 184 /* The sigwrapper unwinder on i386.  */
 185
 186 static const cygwin_sigwrapper_frame_unwind
 187   i386_cygwin_sigwrapper_frame_unwind (i386_sig_patterns);
 188
 189 /* gdbarch initialization for Cygwin on i386.  */
 190
 191 static void
 192 i386_cygwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 193 {
 194   frame_unwind_append_unwinder (gdbarch, &i386_cygwin_sigwrapper_frame_unwind);
 195
 196   i386_windows_init_abi_common (info, gdbarch);
 197   cygwin_init_abi (info, gdbarch);
 198 }
 199
 200 static gdb_osabi
 201 i386_windows_osabi_sniffer (bfd *abfd)
 202 {
 203   const char *target_name = bfd_get_target (abfd);
 204
 205   if (!streq (target_name, "pei-i386"))
 206     return GDB_OSABI_UNKNOWN;
 207
 208   if (is_linked_with_cygwin_dll (abfd))
 209     return GDB_OSABI_CYGWIN;
 210
 211   return GDB_OSABI_WINDOWS;
 212 }
 213
 214 static enum gdb_osabi
 215 i386_cygwin_core_osabi_sniffer (bfd *abfd)
 216 {
 217   const char *target_name = bfd_get_target (abfd);
 218
 219   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 220      check whether there is a .reg section of proper size.  */
 221   if (strcmp (target_name, "elf32-i386") == 0)
 222     {
 223       asection *section = bfd_get_section_by_name (abfd, ".reg");
 224       if (section != nullptr
 225           && bfd_section_size (section) == I386_WINDOWS_SIZEOF_GREGSET)
 226         return GDB_OSABI_CYGWIN;
 227     }
 228
 229   return GDB_OSABI_UNKNOWN;
 230 }
 231
 232 void _initialize_i386_windows_tdep ();
 233 void
 234 _initialize_i386_windows_tdep ()
 235 {
 236   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 237                                   i386_windows_osabi_sniffer);
 238
 239   /* Cygwin uses elf core dumps.  */
 240   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 241                                   i386_cygwin_core_osabi_sniffer);
 242
 243   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_WINDOWS,
 244                           i386_windows_init_abi);
 245   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 246                           i386_cygwin_init_abi);
 247 }