gdb/gdbserver/win32-i386-low.c

   1 /* Copyright (C) 2007, 2008 Free Software Foundation, Inc.
   2
   3    This file is part of GDB.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include "server.h"
  19 #include "win32-low.h"
  20
  21 #define FCS_REGNUM 27
  22 #define FOP_REGNUM 31
  23
  24 #define FLAG_TRACE_BIT 0x100
  25
  26 /* Defined in auto-generated file reg-i386.c.  */
  27 void init_registers_i386 (void);
  28
  29 static unsigned dr[8];
  30
  31 static int debug_registers_changed = 0;
  32 static int debug_registers_used = 0;
  33
  34 static void
  35 i386_initial_stuff (void)
  36 {
  37   memset (&dr, 0, sizeof (dr));
  38   debug_registers_changed = 0;
  39   debug_registers_used = 0;
  40 }
  41
  42 static void
  43 i386_get_thread_context (win32_thread_info *th, DEBUG_EVENT* current_event)
  44 {
  45   th->context.ContextFlags = \
  46     CONTEXT_FULL | \
  47     CONTEXT_FLOATING_POINT | \
  48     CONTEXT_EXTENDED_REGISTERS | \
  49     CONTEXT_DEBUG_REGISTERS;
  50
  51   GetThreadContext (th->h, &th->context);
  52
  53   debug_registers_changed = 0;
  54
  55   if (th->tid == current_event->dwThreadId)
  56     {
  57       /* Copy dr values from the current thread.  */
  58       dr[0] = th->context.Dr0;
  59       dr[1] = th->context.Dr1;
  60       dr[2] = th->context.Dr2;
  61       dr[3] = th->context.Dr3;
  62       dr[6] = th->context.Dr6;
  63       dr[7] = th->context.Dr7;
  64     }
  65 }
  66
  67 static void
  68 i386_set_thread_context (win32_thread_info *th, DEBUG_EVENT* current_event)
  69 {
  70   if (debug_registers_changed)
  71     {
  72       th->context.Dr0 = dr[0];
  73       th->context.Dr1 = dr[1];
  74       th->context.Dr2 = dr[2];
  75       th->context.Dr3 = dr[3];
  76       /* th->context.Dr6 = dr[6];
  77          FIXME: should we set dr6 also ?? */
  78       th->context.Dr7 = dr[7];
  79     }
  80
  81   SetThreadContext (th->h, &th->context);
  82 }
  83
  84 static void
  85 i386_thread_added (win32_thread_info *th)
  86 {
  87   /* Set the debug registers for the new thread if they are used.  */
  88   if (debug_registers_used)
  89     {
  90       th->context.ContextFlags = CONTEXT_DEBUG_REGISTERS;
  91       GetThreadContext (th->h, &th->context);
  92
  93       th->context.Dr0 = dr[0];
  94       th->context.Dr1 = dr[1];
  95       th->context.Dr2 = dr[2];
  96       th->context.Dr3 = dr[3];
  97       /* th->context.Dr6 = dr[6];
  98          FIXME: should we set dr6 also ?? */
  99       th->context.Dr7 = dr[7];
 100
 101       SetThreadContext (th->h, &th->context);
 102       th->context.ContextFlags = 0;
 103     }
 104 }
 105
 106 static void
 107 i386_single_step (win32_thread_info *th)
 108 {
 109   th->context.EFlags |= FLAG_TRACE_BIT;
 110 }
 111
 112 /* An array of offset mappings into a Win32 Context structure.
 113    This is a one-to-one mapping which is indexed by gdb's register
 114    numbers.  It retrieves an offset into the context structure where
 115    the 4 byte register is located.
 116    An offset value of -1 indicates that Win32 does not provide this
 117    register in it's CONTEXT structure.  In this case regptr will return
 118    a pointer into a dummy register.  */
 119 #define context_offset(x) ((int)&(((CONTEXT *)NULL)->x))
 120 static const int mappings[] = {
 121   context_offset (Eax),
 122   context_offset (Ecx),
 123   context_offset (Edx),
 124   context_offset (Ebx),
 125   context_offset (Esp),
 126   context_offset (Ebp),
 127   context_offset (Esi),
 128   context_offset (Edi),
 129   context_offset (Eip),
 130   context_offset (EFlags),
 131   context_offset (SegCs),
 132   context_offset (SegSs),
 133   context_offset (SegDs),
 134   context_offset (SegEs),
 135   context_offset (SegFs),
 136   context_offset (SegGs),
 137   context_offset (FloatSave.RegisterArea[0 * 10]),
 138   context_offset (FloatSave.RegisterArea[1 * 10]),
 139   context_offset (FloatSave.RegisterArea[2 * 10]),
 140   context_offset (FloatSave.RegisterArea[3 * 10]),
 141   context_offset (FloatSave.RegisterArea[4 * 10]),
 142   context_offset (FloatSave.RegisterArea[5 * 10]),
 143   context_offset (FloatSave.RegisterArea[6 * 10]),
 144   context_offset (FloatSave.RegisterArea[7 * 10]),
 145   context_offset (FloatSave.ControlWord),
 146   context_offset (FloatSave.StatusWord),
 147   context_offset (FloatSave.TagWord),
 148   context_offset (FloatSave.ErrorSelector),
 149   context_offset (FloatSave.ErrorOffset),
 150   context_offset (FloatSave.DataSelector),
 151   context_offset (FloatSave.DataOffset),
 152   context_offset (FloatSave.ErrorSelector),
 153   /* XMM0-7 */
 154   context_offset (ExtendedRegisters[10 * 16]),
 155   context_offset (ExtendedRegisters[11 * 16]),
 156   context_offset (ExtendedRegisters[12 * 16]),
 157   context_offset (ExtendedRegisters[13 * 16]),
 158   context_offset (ExtendedRegisters[14 * 16]),
 159   context_offset (ExtendedRegisters[15 * 16]),
 160   context_offset (ExtendedRegisters[16 * 16]),
 161   context_offset (ExtendedRegisters[17 * 16]),
 162   /* MXCSR */
 163   context_offset (ExtendedRegisters[24])
 164 };
 165 #undef context_offset
 166
 167 /* Fetch register from gdbserver regcache data.  */
 168 static void
 169 i386_fetch_inferior_register (win32_thread_info *th, int r)
 170 {
 171   char *context_offset = (char *) &th->context + mappings[r];
 172
 173   long l;
 174   if (r == FCS_REGNUM)
 175     {
 176       l = *((long *) context_offset) & 0xffff;
 177       supply_register (r, (char *) &l);
 178     }
 179   else if (r == FOP_REGNUM)
 180     {
 181       l = (*((long *) context_offset) >> 16) & ((1 << 11) - 1);
 182       supply_register (r, (char *) &l);
 183     }
 184   else
 185     supply_register (r, context_offset);
 186 }
 187
 188 /* Store a new register value into the thread context of TH.  */
 189 static void
 190 i386_store_inferior_register (win32_thread_info *th, int r)
 191 {
 192   char *context_offset = (char *) &th->context + mappings[r];
 193   collect_register (r, context_offset);
 194 }
 195
 196 struct win32_target_ops the_low_target = {
 197   init_registers_i386,
 198   sizeof (mappings) / sizeof (mappings[0]),
 199   i386_initial_stuff,
 200   i386_get_thread_context,
 201   i386_set_thread_context,
 202   i386_thread_added,
 203   i386_fetch_inferior_register,
 204   i386_store_inferior_register,
 205   i386_single_step,
 206   NULL, /* breakpoint */
 207   0, /* breakpoint_len */
 208   "i386" /* arch_string */
 209 };