gdb/gdbserver/win32-i386-low.c - gdb

Global variables defined

Functions defined

Macros defined

Source code

  1. /* Copyright (C) 2007-2015 Free Software Foundation, Inc.

  3.    This file is part of GDB.

  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.

  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.

  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/>.  */

  18. #include "server.h"
  19. #include "win32-low.h"
  20. #include "x86-low.h"

  22. #ifndef CONTEXT_EXTENDED_REGISTERS
  23. ‌#define CONTEXT_EXTENDED_REGISTERS 0
  24. #endif

  26. ‌#define FCS_REGNUM 27
  27. ‌#define FOP_REGNUM 31

  29. ‌#define FLAG_TRACE_BIT 0x100

  31. #ifdef __x86_64__
  32. /* Defined in auto-generated file reg-amd64.c.  */
  33. void init_registers_amd64 (void);
  34. extern const struct target_desc *tdesc_amd64;
  35. #else
  36. /* Defined in auto-generated file reg-i386.c.  */
  37. void init_registers_i386 (void);
  38. extern const struct target_desc *tdesc_i386;
  39. #endif

  41. ‌static struct x86_debug_reg_state debug_reg_state;

  43. static int
  44. ‌update_debug_registers_callback (struct inferior_list_entry *entry,
  45.                                  void *pid_p)
  46. {
  47.   struct thread_info *thr = (struct thread_info *) entry;
  48.   win32_thread_info *th = inferior_target_data (thr);
  49.   int pid = *(int *) pid_p;

  51.   /* Only update the threads of this process.  */
  52.   if (pid_of (thr) == pid)
  53.     {
  54.       /* The actual update is done later just before resuming the lwp,
  55.          we just mark that the registers need updating.  */
  56.       th->debug_registers_changed = 1;
  57.     }

  59.   return 0;
  60. }

  62. /* Update the inferior's debug register REGNUM from STATE.  */

  64. static void
  65. ‌x86_dr_low_set_addr (int regnum, CORE_ADDR addr)
  66. {
  67.   /* Only update the threads of this process.  */
  68.   int pid = pid_of (current_thread);

  70.   gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);

  72.   find_inferior (&all_threads, update_debug_registers_callback, &pid);
  73. }

  75. /* Update the inferior's DR7 debug control register from STATE.  */

  77. static void
  78. ‌x86_dr_low_set_control (unsigned long control)
  79. {
  80.   /* Only update the threads of this process.  */
  81.   int pid = pid_of (current_thread);

  83.   find_inferior (&all_threads, update_debug_registers_callback, &pid);
  84. }

  86. /* Return the current value of a DR register of the current thread's
  87.    context.  */

  89. static DWORD64
  90. ‌win32_get_current_dr (int dr)
  91. {
  92.   win32_thread_info *th = inferior_target_data (current_thread);

  94.   win32_require_context (th);

  96. ‌#define RET_DR(DR)                                \
  97.   case DR:                                        \
  98.     return th->context.Dr ## DR

  100.   switch (dr)
  101.     {
  102.       RET_DR (0);
  103.       RET_DR (1);
  104.       RET_DR (2);
  105.       RET_DR (3);
  106.       RET_DR (6);
  107.       RET_DR (7);
  108.     }

  110. ‌#undef RET_DR

  112.   gdb_assert_not_reached ("unhandled dr");
  113. }

  115. static CORE_ADDR
  116. ‌x86_dr_low_get_addr (int regnum)
  117. {
  118.   gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);

  120.   return win32_get_current_dr (regnum - DR_FIRSTADDR);
  121. }

  123. static unsigned long
  124. ‌x86_dr_low_get_control (void)
  125. {
  126.   return win32_get_current_dr (7);
  127. }

  129. /* Get the value of the DR6 debug status register from the inferior
  130.    and record it in STATE.  */

  132. static unsigned long
  133. ‌x86_dr_low_get_status (void)
  134. {
  135.   return win32_get_current_dr (6);
  136. }

  138. /* Low-level function vector.  */
  139. ‌struct x86_dr_low_type x86_dr_low =
  140.   {
  141.     x86_dr_low_set_control,
  142.     x86_dr_low_set_addr,
  143.     x86_dr_low_get_addr,
  144.     x86_dr_low_get_status,
  145.     x86_dr_low_get_control,
  146.     sizeof (void *),
  147.   };

  149. /* Breakpoint/watchpoint support.  */

  151. static int
  152. ‌i386_supports_z_point_type (char z_type)
  153. {
  154.   switch (z_type)
  155.     {
  156.     case Z_PACKET_WRITE_WP:
  157.     case Z_PACKET_ACCESS_WP:
  158.       return 1;
  159.     default:
  160.       return 0;
  161.     }
  162. }

  164. static int
  165. ‌i386_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
  166.                    int size, struct raw_breakpoint *bp)
  167. {
  168.   switch (type)
  169.     {
  170.     case raw_bkpt_type_write_wp:
  171.     case raw_bkpt_type_access_wp:
  172.       {
  173.         enum target_hw_bp_type hw_type
  174.           = raw_bkpt_type_to_target_hw_bp_type (type);

  176.         return x86_dr_insert_watchpoint (&debug_reg_state,
  177.                                          hw_type, addr, size);
  178.       }
  179.     default:
  180.       /* Unsupported.  */
  181.       return 1;
  182.     }
  183. }

  185. static int
  186. ‌i386_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
  187.                    int size, struct raw_breakpoint *bp)
  188. {
  189.   switch (type)
  190.     {
  191.     case raw_bkpt_type_write_wp:
  192.     case raw_bkpt_type_access_wp:
  193.       {
  194.         enum target_hw_bp_type hw_type
  195.           = raw_bkpt_type_to_target_hw_bp_type (type);

  197.         return x86_dr_remove_watchpoint (&debug_reg_state,
  198.                                          hw_type, addr, size);
  199.       }
  200.     default:
  201.       /* Unsupported.  */
  202.       return 1;
  203.     }
  204. }

  206. static int
  207. ‌x86_stopped_by_watchpoint (void)
  208. {
  209.   return x86_dr_stopped_by_watchpoint (&debug_reg_state);
  210. }

  212. static CORE_ADDR
  213. ‌x86_stopped_data_address (void)
  214. {
  215.   CORE_ADDR addr;
  216.   if (x86_dr_stopped_data_address (&debug_reg_state, &addr))
  217.     return addr;
  218.   return 0;
  219. }

  221. static void
  222. ‌i386_initial_stuff (void)
  223. {
  224.   x86_low_init_dregs (&debug_reg_state);
  225. }

  227. static void
  228. ‌i386_get_thread_context (win32_thread_info *th)
  229. {
  230.   /* Requesting the CONTEXT_EXTENDED_REGISTERS register set fails if
  231.      the system doesn't support extended registers.  */
  232.   static DWORD extended_registers = CONTEXT_EXTENDED_REGISTERS;

  234. again:
  235.   th->context.ContextFlags = (CONTEXT_FULL
  236.                               | CONTEXT_FLOATING_POINT
  237.                               | CONTEXT_DEBUG_REGISTERS
  238.                               | extended_registers);

  240.   if (!GetThreadContext (th->h, &th->context))
  241.     {
  242.       DWORD e = GetLastError ();

  244.       if (extended_registers && e == ERROR_INVALID_PARAMETER)
  245.         {
  246.           extended_registers = 0;
  247.           goto again;
  248.         }

  250.       error ("GetThreadContext failure %ld\n", (long) e);
  251.     }
  252. }

  254. static void
  255. ‌i386_prepare_to_resume (win32_thread_info *th)
  256. {
  257.   if (th->debug_registers_changed)
  258.     {
  259.       struct x86_debug_reg_state *dr = &debug_reg_state;

  261.       win32_require_context (th);

  263.       th->context.Dr0 = dr->dr_mirror[0];
  264.       th->context.Dr1 = dr->dr_mirror[1];
  265.       th->context.Dr2 = dr->dr_mirror[2];
  266.       th->context.Dr3 = dr->dr_mirror[3];
  267.       /* th->context.Dr6 = dr->dr_status_mirror;
  268.          FIXME: should we set dr6 also ?? */
  269.       th->context.Dr7 = dr->dr_control_mirror;

  271.       th->debug_registers_changed = 0;
  272.     }
  273. }

  275. static void
  276. ‌i386_thread_added (win32_thread_info *th)
  277. {
  278.   th->debug_registers_changed = 1;
  279. }

  281. static void
  282. ‌i386_single_step (win32_thread_info *th)
  283. {
  284.   th->context.EFlags |= FLAG_TRACE_BIT;
  285. }

  287. #ifndef __x86_64__

  289. /* An array of offset mappings into a Win32 Context structure.
  290.    This is a one-to-one mapping which is indexed by gdb's register
  291.    numbers.  It retrieves an offset into the context structure where
  292.    the 4 byte register is located.
  293.    An offset value of -1 indicates that Win32 does not provide this
  294.    register in it's CONTEXT structure.  In this case regptr will return
  295.    a pointer into a dummy register.  */
  296. ‌#define context_offset(x) ((int)&(((CONTEXT *)NULL)->x))
  297. ‌static const int mappings[] = {
  298.   context_offset (Eax),
  299.   context_offset (Ecx),
  300.   context_offset (Edx),
  301.   context_offset (Ebx),
  302.   context_offset (Esp),
  303.   context_offset (Ebp),
  304.   context_offset (Esi),
  305.   context_offset (Edi),
  306.   context_offset (Eip),
  307.   context_offset (EFlags),
  308.   context_offset (SegCs),
  309.   context_offset (SegSs),
  310.   context_offset (SegDs),
  311.   context_offset (SegEs),
  312.   context_offset (SegFs),
  313.   context_offset (SegGs),
  314.   context_offset (FloatSave.RegisterArea[0 * 10]),
  315.   context_offset (FloatSave.RegisterArea[1 * 10]),
  316.   context_offset (FloatSave.RegisterArea[2 * 10]),
  317.   context_offset (FloatSave.RegisterArea[3 * 10]),
  318.   context_offset (FloatSave.RegisterArea[4 * 10]),
  319.   context_offset (FloatSave.RegisterArea[5 * 10]),
  320.   context_offset (FloatSave.RegisterArea[6 * 10]),
  321.   context_offset (FloatSave.RegisterArea[7 * 10]),
  322.   context_offset (FloatSave.ControlWord),
  323.   context_offset (FloatSave.StatusWord),
  324.   context_offset (FloatSave.TagWord),
  325.   context_offset (FloatSave.ErrorSelector),
  326.   context_offset (FloatSave.ErrorOffset),
  327.   context_offset (FloatSave.DataSelector),
  328.   context_offset (FloatSave.DataOffset),
  329.   context_offset (FloatSave.ErrorSelector),
  330.   /* XMM0-7 */
  331.   context_offset (ExtendedRegisters[10 * 16]),
  332.   context_offset (ExtendedRegisters[11 * 16]),
  333.   context_offset (ExtendedRegisters[12 * 16]),
  334.   context_offset (ExtendedRegisters[13 * 16]),
  335.   context_offset (ExtendedRegisters[14 * 16]),
  336.   context_offset (ExtendedRegisters[15 * 16]),
  337.   context_offset (ExtendedRegisters[16 * 16]),
  338.   context_offset (ExtendedRegisters[17 * 16]),
  339.   /* MXCSR */
  340.   context_offset (ExtendedRegisters[24])
  341. };
  342. ‌#undef context_offset

  344. #else /* __x86_64__ */

  346. ‌#define context_offset(x) (offsetof (CONTEXT, x))
  347. ‌static const int mappings[] =
  348. {
  349.   context_offset (Rax),
  350.   context_offset (Rbx),
  351.   context_offset (Rcx),
  352.   context_offset (Rdx),
  353.   context_offset (Rsi),
  354.   context_offset (Rdi),
  355.   context_offset (Rbp),
  356.   context_offset (Rsp),
  357.   context_offset (R8),
  358.   context_offset (R9),
  359.   context_offset (R10),
  360.   context_offset (R11),
  361.   context_offset (R12),
  362.   context_offset (R13),
  363.   context_offset (R14),
  364.   context_offset (R15),
  365.   context_offset (Rip),
  366.   context_offset (EFlags),
  367.   context_offset (SegCs),
  368.   context_offset (SegSs),
  369.   context_offset (SegDs),
  370.   context_offset (SegEs),
  371.   context_offset (SegFs),
  372.   context_offset (SegGs),
  373.   context_offset (FloatSave.FloatRegisters[0]),
  374.   context_offset (FloatSave.FloatRegisters[1]),
  375.   context_offset (FloatSave.FloatRegisters[2]),
  376.   context_offset (FloatSave.FloatRegisters[3]),
  377.   context_offset (FloatSave.FloatRegisters[4]),
  378.   context_offset (FloatSave.FloatRegisters[5]),
  379.   context_offset (FloatSave.FloatRegisters[6]),
  380.   context_offset (FloatSave.FloatRegisters[7]),
  381.   context_offset (FloatSave.ControlWord),
  382.   context_offset (FloatSave.StatusWord),
  383.   context_offset (FloatSave.TagWord),
  384.   context_offset (FloatSave.ErrorSelector),
  385.   context_offset (FloatSave.ErrorOffset),
  386.   context_offset (FloatSave.DataSelector),
  387.   context_offset (FloatSave.DataOffset),
  388.   context_offset (FloatSave.ErrorSelector)
  389.   /* XMM0-7 */ ,
  390.   context_offset (Xmm0),
  391.   context_offset (Xmm1),
  392.   context_offset (Xmm2),
  393.   context_offset (Xmm3),
  394.   context_offset (Xmm4),
  395.   context_offset (Xmm5),
  396.   context_offset (Xmm6),
  397.   context_offset (Xmm7),
  398.   context_offset (Xmm8),
  399.   context_offset (Xmm9),
  400.   context_offset (Xmm10),
  401.   context_offset (Xmm11),
  402.   context_offset (Xmm12),
  403.   context_offset (Xmm13),
  404.   context_offset (Xmm14),
  405.   context_offset (Xmm15),
  406.   /* MXCSR */
  407.   context_offset (FloatSave.MxCsr)
  408. };
  409. ‌#undef context_offset

  411. #endif /* __x86_64__ */

  413. /* Fetch register from gdbserver regcache data.  */
  414. static void
  415. ‌i386_fetch_inferior_register (struct regcache *regcache,
  416.                               win32_thread_info *th, int r)
  417. {
  418.   char *context_offset = (char *) &th->context + mappings[r];

  420.   long l;
  421.   if (r == FCS_REGNUM)
  422.     {
  423.       l = *((long *) context_offset) & 0xffff;
  424.       supply_register (regcache, r, (char *) &l);
  425.     }
  426.   else if (r == FOP_REGNUM)
  427.     {
  428.       l = (*((long *) context_offset) >> 16) & ((1 << 11) - 1);
  429.       supply_register (regcache, r, (char *) &l);
  430.     }
  431.   else
  432.     supply_register (regcache, r, context_offset);
  433. }

  435. /* Store a new register value into the thread context of TH.  */
  436. static void
  437. ‌i386_store_inferior_register (struct regcache *regcache,
  438.                               win32_thread_info *th, int r)
  439. {
  440.   char *context_offset = (char *) &th->context + mappings[r];
  441.   collect_register (regcache, r, context_offset);
  442. }

  444. ‌static const unsigned char i386_win32_breakpoint = 0xcc;
  445. ‌#define i386_win32_breakpoint_len 1

  447. static void
  448. ‌i386_arch_setup (void)
  449. {
  450. #ifdef __x86_64__
  451.   init_registers_amd64 ();
  452.   win32_tdesc = tdesc_amd64;
  453. #else
  454.   init_registers_i386 ();
  455.   win32_tdesc = tdesc_i386;
  456. #endif
  457. }

  459. ‌struct win32_target_ops the_low_target = {
  460.   i386_arch_setup,
  461.   sizeof (mappings) / sizeof (mappings[0]),
  462.   i386_initial_stuff,
  463.   i386_get_thread_context,
  464.   i386_prepare_to_resume,
  465.   i386_thread_added,
  466.   i386_fetch_inferior_register,
  467.   i386_store_inferior_register,
  468.   i386_single_step,
  469.   &i386_win32_breakpoint,
  470.   i386_win32_breakpoint_len,
  471.   i386_supports_z_point_type,
  472.   i386_insert_point,
  473.   i386_remove_point,
  474.   x86_stopped_by_watchpoint,
  475.   x86_stopped_data_address
  476. };