gdb/mips-linux-nat.c

   1 /* Native-dependent code for GNU/Linux on MIPS processors.
   2
   3    Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
   4    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 2 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, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21    Boston, MA 02110-1301, USA.  */
  22
  23 #include "defs.h"
  24 #include "mips-tdep.h"
  25 #include "target.h"
  26 #include "linux-nat.h"
  27
  28 #include "gdb_proc_service.h"
  29
  30 #ifndef PTRACE_GET_THREAD_AREA
  31 #define PTRACE_GET_THREAD_AREA 25
  32 #endif
  33
  34 /* Pseudo registers can not be read.  ptrace does not provide a way to
  35    read (or set) MIPS_PS_REGNUM, and there's no point in reading or
  36    setting MIPS_ZERO_REGNUM.  We also can not set BADVADDR, CAUSE, or
  37    FCRIR via ptrace().  */
  38
  39 int
  40 mips_linux_cannot_fetch_register (int regno)
  41 {
  42   if (regno > MIPS_ZERO_REGNUM && regno < MIPS_ZERO_REGNUM + 32)
  43     return 0;
  44   else if (regno >= mips_regnum (current_gdbarch)->fp0
  45            && regno <= mips_regnum (current_gdbarch)->fp0 + 32)
  46     return 0;
  47   else if (regno == mips_regnum (current_gdbarch)->lo
  48            || regno == mips_regnum (current_gdbarch)->hi
  49            || regno == mips_regnum (current_gdbarch)->badvaddr
  50            || regno == mips_regnum (current_gdbarch)->cause
  51            || regno == mips_regnum (current_gdbarch)->pc
  52            || regno == mips_regnum (current_gdbarch)->fp_control_status
  53            || regno == mips_regnum (current_gdbarch)->fp_implementation_revision)
  54     return 0;
  55   else
  56     return 1;
  57 }
  58
  59 int
  60 mips_linux_cannot_store_register (int regno)
  61 {
  62   if (regno > MIPS_ZERO_REGNUM && regno < MIPS_ZERO_REGNUM + 32)
  63     return 0;
  64   else if (regno >= FP0_REGNUM && regno <= FP0_REGNUM + 32)
  65     return 0;
  66   else if (regno == mips_regnum (current_gdbarch)->lo
  67            || regno == mips_regnum (current_gdbarch)->hi
  68            || regno == mips_regnum (current_gdbarch)->pc
  69            || regno == mips_regnum (current_gdbarch)->fp_control_status)
  70     return 0;
  71   else
  72     return 1;
  73 }
  74
  75 /* Fetch the thread-local storage pointer for libthread_db.  */
  76
  77 ps_err_e
  78 ps_get_thread_area (const struct ps_prochandle *ph,
  79                     lwpid_t lwpid, int idx, void **base)
  80 {
  81   if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
  82     return PS_ERR;
  83
  84   /* IDX is the bias from the thread pointer to the beginning of the
  85      thread descriptor.  It has to be subtracted due to implementation
  86      quirks in libthread_db.  */
  87   *base = (void *) ((char *)*base - idx);
  88
  89   return PS_OK;
  90 }
  91
  92 void _initialize_mips_linux_nat (void);
  93
  94 void
  95 _initialize_mips_linux_nat (void)
  96 {
  97   add_target (linux_target ());
  98 }