binutils-gdb/gdb/nat/aarch64-linux.c

/* Copyright (C) 2009-2015 Free Software Foundation, Inc.
   Contributed by ARM Ltd.

   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 "common-defs.h"
#include "break-common.h"
#include "nat/linux-nat.h"
#include "nat/aarch64-linux-hw-point.h"
#include "nat/aarch64-linux.h"

/* Called when resuming a thread LWP.
   The hardware debug registers are updated when there is any change.  */

void
aarch64_linux_prepare_to_resume (struct lwp_info *lwp)
{
  struct arch_lwp_info *info = lwp_arch_private_info (lwp);

  /* NULL means this is the main thread still going through the shell,
     or, no watchpoint has been set yet.  In that case, there's
     nothing to do.  */
  if (info == NULL)
    return;

  if (DR_HAS_CHANGED (info->dr_changed_bp)
      || DR_HAS_CHANGED (info->dr_changed_wp))
    {
      ptid_t ptid = ptid_of_lwp (lwp);
      int tid = ptid_get_lwp (ptid);
      struct aarch64_debug_reg_state *state
	= aarch64_get_debug_reg_state (ptid_get_pid (ptid));

      if (show_debug_regs)
	debug_printf ("prepare_to_resume thread %d\n", tid);

      /* Watchpoints.  */
      if (DR_HAS_CHANGED (info->dr_changed_wp))
	{
	  aarch64_linux_set_debug_regs (state, tid, 1);
	  DR_CLEAR_CHANGED (info->dr_changed_wp);
	}

      /* Breakpoints.  */
      if (DR_HAS_CHANGED (info->dr_changed_bp))
	{
	  aarch64_linux_set_debug_regs (state, tid, 0);
	  DR_CLEAR_CHANGED (info->dr_changed_bp);
	}
    }
}

/* Function to call when a new thread is detected.  */

void
aarch64_linux_new_thread (struct lwp_info *lwp)
{
  struct arch_lwp_info *info = XNEW (struct arch_lwp_info);

  /* Mark that all the hardware breakpoint/watchpoint register pairs
     for this thread need to be initialized (with data from
     aarch_process_info.debug_reg_state).  */
  DR_MARK_ALL_CHANGED (info->dr_changed_bp, aarch64_num_bp_regs);
  DR_MARK_ALL_CHANGED (info->dr_changed_wp, aarch64_num_wp_regs);

  lwp_set_arch_private_info (lwp, info);
}