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 "defs.h"
  22 #include "osabi.h"
  23 #include "i386-tdep.h"
  24 #include "windows-tdep.h"
  25 #include "regset.h"
  26 #include "gdbsupport/gdb_obstack.h"
  27 #include "xml-support.h"
  28 #include "gdbcore.h"
  29 #include "inferior.h"
  30 #include "frame-unwind.h"
  31
  32 /* Core file support.  */
  33
  34 /* This vector maps GDB's idea of a register's number into an address
  35    in the windows exception context vector.  */
  36
  37 static int i386_windows_gregset_reg_offset[] =
  38 {
  39   176, /* eax */
  40   172, /* ecx */
  41   168, /* edx */
  42   164, /* ebx */
  43
  44   196, /* esp */
  45   180, /* ebp */
  46   160, /* esi */
  47   156, /* edi */
  48
  49   184, /* eip */
  50   192, /* eflags */
  51   188, /* cs */
  52   200, /* ss */
  53
  54   152, /* ds */
  55   148, /* es */
  56   144, /* fs */
  57   140, /* gs */
  58
  59   56, /* FloatSave.RegisterArea[0 * 10] */
  60   66, /* FloatSave.RegisterArea[1 * 10] */
  61   76, /* FloatSave.RegisterArea[2 * 10] */
  62   86, /* FloatSave.RegisterArea[3 * 10] */
  63   96, /* FloatSave.RegisterArea[4 * 10] */
  64   106, /* FloatSave.RegisterArea[5 * 10] */
  65   116, /* FloatSave.RegisterArea[6 * 10] */
  66   126, /* FloatSave.RegisterArea[7 * 10] */
  67
  68   28, /* FloatSave.ControlWord */
  69   32, /* FloatSave.StatusWord */
  70   36, /* FloatSave.TagWord */
  71   44, /* FloatSave.ErrorSelector */
  72   40, /* FloatSave.ErrorOffset */
  73   52, /* FloatSave.DataSelector */
  74   48, /* FloatSave.DataOffset */
  75   44, /* FloatSave.ErrorSelector */
  76
  77   /* XMM0-7 */
  78   364, /* ExtendedRegisters[10*16] */
  79   380, /* ExtendedRegisters[11*16] */
  80   396, /* ExtendedRegisters[12*16] */
  81   412, /* ExtendedRegisters[13*16] */
  82   428, /* ExtendedRegisters[14*16] */
  83   444, /* ExtendedRegisters[15*16] */
  84   460, /* ExtendedRegisters[16*16] */
  85   476, /* ExtendedRegisters[17*16] */
  86
  87   /* MXCSR */
  88   228 /* ExtendedRegisters[24] */
  89 };
  90
  91 #define I386_WINDOWS_SIZEOF_GREGSET 716
  92
  93 static CORE_ADDR
  94 i386_windows_skip_trampoline_code (const frame_info_ptr &frame, CORE_ADDR pc)
  95 {
  96   return i386_pe_skip_trampoline_code (frame, pc, NULL);
  97 }
  98
  99 static const char *
 100 i386_windows_auto_wide_charset (void)
 101 {
 102   return "UTF-16";
 103 }
 104
 105 /* Implement the "push_dummy_call" gdbarch method.  */
 106
 107 static CORE_ADDR
 108 i386_windows_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
 109                               struct regcache *regcache, CORE_ADDR bp_addr,
 110                               int nargs, struct value **args, CORE_ADDR sp,
 111                               function_call_return_method return_method,
 112                               CORE_ADDR struct_addr)
 113 {
 114   /* For non-static member functions of 32bit Windows programs, the thiscall
 115      calling convention is used, so the 'this' pointer is passed in ECX.  */
 116   bool thiscall = false;
 117
 118   struct type *type = check_typedef (function->type ());
 119   if (type->code () == TYPE_CODE_PTR)
 120     type = check_typedef (type->target_type ());
 121
 122   /* read_subroutine_type sets for non-static member functions the
 123      artificial flag of the first parameter ('this' pointer).  */
 124   if (type->code () == TYPE_CODE_METHOD
 125       && type->num_fields () > 0
 126       && type->field (0).is_artificial ()
 127       && type->field (0).type ()->code () == TYPE_CODE_PTR)
 128     thiscall = 1;
 129
 130   return i386_thiscall_push_dummy_call (gdbarch, function, regcache, bp_addr,
 131                                         nargs, args, sp, return_method,
 132                                         struct_addr, thiscall);
 133 }
 134
 135 /* Common parts for gdbarch initialization for Windows and Cygwin on i386.  */
 136
 137 static void
 138 i386_windows_init_abi_common (struct gdbarch_info info, struct gdbarch *gdbarch)
 139 {
 140   i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch);
 141
 142   set_gdbarch_skip_trampoline_code (gdbarch, i386_windows_skip_trampoline_code);
 143
 144   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 145
 146   tdep->struct_return = reg_struct_return;
 147
 148   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 149   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 150   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 151
 152   tdep->sizeof_fpregset = 0;
 153
 154   /* Core file support.  */
 155   set_gdbarch_core_xfer_shared_libraries
 156     (gdbarch, windows_core_xfer_shared_libraries);
 157   set_gdbarch_core_pid_to_str (gdbarch, windows_core_pid_to_str);
 158
 159   set_gdbarch_auto_wide_charset (gdbarch, i386_windows_auto_wide_charset);
 160 }
 161
 162 /* gdbarch initialization for Windows on i386.  */
 163
 164 static void
 165 i386_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 166 {
 167   i386_windows_init_abi_common (info, gdbarch);
 168   windows_init_abi (info, gdbarch);
 169
 170   set_gdbarch_push_dummy_call (gdbarch, i386_windows_push_dummy_call);
 171 }
 172
 173 /* Sigwrapper unwinder instruction patterns for i386.  */
 174
 175 static const gdb_byte i386_sigbe_bytes[] = {
 176   0xb8, 0xfc, 0xff, 0xff, 0xff,                 /* movl $-4,%eax */
 177   0x0f, 0xc1, 0x83,                             /* xadd %eax,$tls::stackptr(%ebx) */
 178   /* 4 bytes for tls::stackptr operand.  */
 179 };
 180
 181 static const gdb::array_view<const gdb_byte> i386_sig_patterns[] {
 182   { i386_sigbe_bytes },
 183 };
 184
 185 /* The sigwrapper unwinder on i386.  */
 186
 187 static const cygwin_sigwrapper_frame_unwind
 188   i386_cygwin_sigwrapper_frame_unwind (i386_sig_patterns);
 189
 190 /* gdbarch initialization for Cygwin on i386.  */
 191
 192 static void
 193 i386_cygwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 194 {
 195   frame_unwind_append_unwinder (gdbarch, &i386_cygwin_sigwrapper_frame_unwind);
 196
 197   i386_windows_init_abi_common (info, gdbarch);
 198   cygwin_init_abi (info, gdbarch);
 199 }
 200
 201 static gdb_osabi
 202 i386_windows_osabi_sniffer (bfd *abfd)
 203 {
 204   const char *target_name = bfd_get_target (abfd);
 205
 206   if (!streq (target_name, "pei-i386"))
 207     return GDB_OSABI_UNKNOWN;
 208
 209   if (is_linked_with_cygwin_dll (abfd))
 210     return GDB_OSABI_CYGWIN;
 211
 212   return GDB_OSABI_WINDOWS;
 213 }
 214
 215 static enum gdb_osabi
 216 i386_cygwin_core_osabi_sniffer (bfd *abfd)
 217 {
 218   const char *target_name = bfd_get_target (abfd);
 219
 220   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 221      check whether there is a .reg section of proper size.  */
 222   if (strcmp (target_name, "elf32-i386") == 0)
 223     {
 224       asection *section = bfd_get_section_by_name (abfd, ".reg");
 225       if (section != nullptr
 226           && bfd_section_size (section) == I386_WINDOWS_SIZEOF_GREGSET)
 227         return GDB_OSABI_CYGWIN;
 228     }
 229
 230   return GDB_OSABI_UNKNOWN;
 231 }
 232
 233 void _initialize_i386_windows_tdep ();
 234 void
 235 _initialize_i386_windows_tdep ()
 236 {
 237   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 238                                   i386_windows_osabi_sniffer);
 239
 240   /* Cygwin uses elf core dumps.  */
 241   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 242                                   i386_cygwin_core_osabi_sniffer);
 243
 244   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_WINDOWS,
 245                           i386_windows_init_abi);
 246   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 247                           i386_cygwin_init_abi);
 248 }