gdb/xtensa-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux on Xtensa processors.
   2
   3    Copyright (C) 2007-2016 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "osabi.h"
  22 #include "linux-tdep.h"
  23 #include "solib-svr4.h"
  24 #include "symtab.h"
  25
  26 /* This enum represents the signals' numbers on the Xtensa
  27    architecture.  It just contains the signal definitions which are
  28    different from the generic implementation.
  29
  30    It is derived from the file <arch/xtensa/include/uapi/asm/signal.h>,
  31    from the Linux kernel tree.  */
  32
  33 enum
  34   {
  35     XTENSA_LINUX_SIGRTMIN = 32,
  36     XTENSA_LINUX_SIGRTMAX = 63,
  37   };
  38
  39 /* Implementation of `gdbarch_gdb_signal_from_target', as defined in
  40    gdbarch.h.  */
  41
  42 static enum gdb_signal
  43 xtensa_linux_gdb_signal_from_target (struct gdbarch *gdbarch,
  44                                    int signal)
  45 {
  46   if (signal >= XTENSA_LINUX_SIGRTMIN && signal <= XTENSA_LINUX_SIGRTMAX)
  47     {
  48       int offset = signal - XTENSA_LINUX_SIGRTMIN;
  49
  50       if (offset == 0)
  51         return GDB_SIGNAL_REALTIME_32;
  52       else
  53         return (enum gdb_signal) (offset - 1
  54                                   + (int) GDB_SIGNAL_REALTIME_33);
  55     }
  56   else if (signal > XTENSA_LINUX_SIGRTMAX)
  57     return GDB_SIGNAL_UNKNOWN;
  58
  59   return linux_gdb_signal_from_target (gdbarch, signal);
  60 }
  61
  62 /* Implementation of `gdbarch_gdb_signal_to_target', as defined in
  63    gdbarch.h.  */
  64
  65 static int
  66 xtensa_linux_gdb_signal_to_target (struct gdbarch *gdbarch,
  67                                    enum gdb_signal signal)
  68 {
  69   switch (signal)
  70     {
  71     /* GDB_SIGNAL_REALTIME_32 is not continuous in <gdb/signals.def>,
  72        therefore we have to handle it here.  */
  73     case GDB_SIGNAL_REALTIME_32:
  74       return XTENSA_LINUX_SIGRTMIN;
  75
  76     /* GDB_SIGNAL_REALTIME_64 is not valid on Xtensa.  */
  77     case GDB_SIGNAL_REALTIME_64:
  78       return -1;
  79     }
  80
  81   /* GDB_SIGNAL_REALTIME_33 to _63 are continuous.
  82
  83      Xtensa does not have _64.  */
  84   if (signal >= GDB_SIGNAL_REALTIME_33
  85       && signal <= GDB_SIGNAL_REALTIME_63)
  86     {
  87       int offset = signal - GDB_SIGNAL_REALTIME_33;
  88
  89       return XTENSA_LINUX_SIGRTMIN + 1 + offset;
  90     }
  91
  92   return linux_gdb_signal_to_target (gdbarch, signal);
  93 }
  94
  95 /* OS specific initialization of gdbarch.  */
  96
  97 static void
  98 xtensa_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  99 {
 100   linux_init_abi (info, gdbarch);
 101
 102   set_solib_svr4_fetch_link_map_offsets
 103     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 104
 105   set_gdbarch_gdb_signal_from_target (gdbarch,
 106                                       xtensa_linux_gdb_signal_from_target);
 107   set_gdbarch_gdb_signal_to_target (gdbarch,
 108                                     xtensa_linux_gdb_signal_to_target);
 109
 110   /* Enable TLS support.  */
 111   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 112                                              svr4_fetch_objfile_link_map);
 113 }
 114
 115 /* Provide a prototype to silence -Wmissing-prototypes.  */
 116 extern initialize_file_ftype _initialize_xtensa_linux_tdep;
 117
 118 void
 119 _initialize_xtensa_linux_tdep (void)
 120 {
 121   gdbarch_register_osabi (bfd_arch_xtensa, bfd_mach_xtensa, GDB_OSABI_LINUX,
 122                           xtensa_linux_init_abi);
 123 }