gdb/ia64-hpux-tdep.c

   1 /* Target-dependent code for the IA-64 for GDB, the GNU debugger.
   2
   3    Copyright (C) 2010 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 "ia64-tdep.h"
  22 #include "ia64-hpux-tdep.h"
  23 #include "osabi.h"
  24 #include "gdbtypes.h"
  25 #include "solib.h"
  26 #include "target.h"
  27 #include "frame.h"
  28
  29 /* The offset to be used in order to get the __reason pseudo-register
  30    when using one of the *UREGS ttrace requests (see system header file
  31    /usr/include/ia64/sys/uregs.h for more details).
  32
  33    The documentation for this pseudo-register says that a nonzero value
  34    indicates that the thread stopped due to a fault, trap, or interrupt.
  35    A null value indicates a stop inside a syscall.  */
  36 #define IA64_HPUX_UREG_REASON 0x00070000
  37
  38 /* Return nonzero if the value of the register identified by REGNUM
  39    can be modified.  */
  40
  41 static int
  42 ia64_hpux_can_store_ar_register (int regnum)
  43 {
  44   switch (regnum)
  45     {
  46       case IA64_RSC_REGNUM:
  47       case IA64_RNAT_REGNUM:
  48       case IA64_CSD_REGNUM:
  49       case IA64_SSD_REGNUM:
  50       case IA64_CCV_REGNUM:
  51       case IA64_UNAT_REGNUM:
  52       case IA64_FPSR_REGNUM:
  53       case IA64_PFS_REGNUM:
  54       case IA64_LC_REGNUM:
  55       case IA64_EC_REGNUM:
  56          return 1;
  57          break;
  58
  59       default:
  60          return 0;
  61          break;
  62     }
  63 }
  64
  65 /* The "cannot_store_register" target_ops method.  */
  66
  67 static int
  68 ia64_hpux_cannot_store_register (struct gdbarch *gdbarch, int regnum)
  69 {
  70   /* General registers.  */
  71
  72   if (regnum == IA64_GR0_REGNUM)
  73     return 1;
  74
  75   /* FP register.  */
  76
  77   if (regnum == IA64_FR0_REGNUM || regnum == IA64_FR1_REGNUM)
  78     return 1;
  79
  80   /* Application registers.  */
  81   if (regnum >= IA64_AR0_REGNUM && regnum <= IA64_AR0_REGNUM + 127)
  82     return (!ia64_hpux_can_store_ar_register (regnum));
  83
  84   /* We can store all other registers.  */
  85   return 0;
  86 }
  87
  88 /* Return nonzero if the inferior is stopped inside a system call.  */
  89
  90 static int
  91 ia64_hpux_stopped_in_syscall (struct gdbarch *gdbarch)
  92 {
  93   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  94   struct target_ops *ops = &current_target;
  95   gdb_byte buf[8];
  96   int len;
  97
  98   len = target_read (ops, TARGET_OBJECT_HPUX_UREGS, NULL,
  99                      buf, IA64_HPUX_UREG_REASON, sizeof (buf));
 100   if (len == -1)
 101     /* The target wasn't able to tell us.  Assume we are not stopped
 102        in a system call, which is the normal situation.  */
 103     return 0;
 104   gdb_assert (len == 8);
 105
 106   return (extract_unsigned_integer (buf, len, byte_order) == 0);
 107 }
 108
 109 /* The "size_of_register_frame" gdbarch_tdep routine for ia64-hpux.  */
 110
 111 static int
 112 ia64_hpux_size_of_register_frame (struct frame_info *this_frame,
 113                                   ULONGEST cfm)
 114 {
 115   int sof;
 116
 117   if (frame_relative_level (this_frame) == 0
 118       && ia64_hpux_stopped_in_syscall (get_frame_arch (this_frame)))
 119     /* If the inferior stopped in a system call, the base address
 120        of the register frame is at BSP - SOL instead of BSP - SOF.
 121        This is an HP-UX exception.  */
 122     sof = (cfm & 0x3f80) >> 7;
 123   else
 124     sof = (cfm & 0x7f);
 125
 126   return sof;
 127 }
 128
 129 /* Should be set to non-NULL if the ia64-hpux solib module is linked in.
 130    This may not be the case because the shared library support code can
 131    only be compiled on ia64-hpux.  */
 132
 133 struct target_so_ops *ia64_hpux_so_ops = NULL;
 134
 135 static void
 136 ia64_hpux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 137 {
 138   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 139
 140   tdep->size_of_register_frame = ia64_hpux_size_of_register_frame;
 141
 142   set_gdbarch_long_double_format (gdbarch, floatformats_ia64_quad);
 143   set_gdbarch_cannot_store_register (gdbarch, ia64_hpux_cannot_store_register);
 144
 145   if (ia64_hpux_so_ops)
 146     set_solib_ops (gdbarch, ia64_hpux_so_ops);
 147 }
 148
 149 /* Provide a prototype to silence -Wmissing-prototypes.  */
 150 extern initialize_file_ftype _initialize_ia64_hpux_tdep;
 151
 152 void
 153 _initialize_ia64_hpux_tdep (void)
 154 {
 155   gdbarch_register_osabi (bfd_arch_ia64, 0, GDB_OSABI_HPUX_ELF,
 156                           ia64_hpux_init_abi);
 157 }