gdb/tilegx-linux-nat.c

   1 /* Native-dependent code for GNU/Linux TILE-Gx.
   2
   3    Copyright (C) 2012-2024 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 "inferior.h"
  21 #include "gdbcore.h"
  22 #include "regcache.h"
  23 #include "linux-nat.h"
  24 #include "inf-ptrace.h"
  25
  26 #include "nat/gdb_ptrace.h"
  27
  28 #include <sys/procfs.h>
  29
  30 /* Defines ps_err_e, struct ps_prochandle.  */
  31 #include "gdb_proc_service.h"
  32
  33 /* Prototypes for supply_gregset etc.  */
  34 #include "gregset.h"
  35
  36 class tilegx_linux_nat_target final : public linux_nat_target
  37 {
  38 public:
  39   /* Add our register access methods.  */
  40   void fetch_registers (struct regcache *, int) override;
  41   void store_registers (struct regcache *, int) override;
  42 };
  43
  44 static tilegx_linux_nat_target the_tilegx_linux_nat_target;
  45
  46 /* The register sets used in GNU/Linux ELF core-dumps are identical to
  47    the register sets in `struct user' that is used for a.out
  48    core-dumps, and is also used by `ptrace'.  The corresponding types
  49    are `elf_gregset_t' for the general-purpose registers (with
  50    `elf_greg_t' the type of a single GP register) and `elf_fpregset_t'
  51    for the floating-point registers.
  52
  53    Those types used to be available under the names `gregset_t' and
  54    `fpregset_t' too, and this file used those names in the past.  But
  55    those names are now used for the register sets used in the
  56    `mcontext_t' type, and have a different size and layout.  */
  57
  58 /* Mapping between the general-purpose registers in `struct user'
  59    format and GDB's register array layout.  Note that we map the
  60    first 56 registers (0 thru 55) one-to-one.  GDB maps the pc to
  61    slot 64, but ptrace returns it in slot 56.  */
  62 static const int regmap[] =
  63 {
  64    0,  1,  2,  3,  4,  5,  6,  7,
  65    8,  9, 10, 11, 12, 13, 14, 15,
  66   16, 17, 18, 19, 20, 21, 22, 23,
  67   24, 25, 26, 27, 28, 29, 30, 31,
  68   32, 33, 34, 35, 36, 37, 38, 39,
  69   40, 41, 42, 43, 44, 45, 46, 47,
  70   48, 49, 50, 51, 52, 53, 54, 55,
  71   -1, -1, -1, -1, -1, -1, -1, -1,
  72   56, 58
  73 };
  74
  75 /* Transfering the general-purpose registers between GDB, inferiors
  76    and core files.  */
  77
  78 /* Fill GDB's register array with the general-purpose register values
  79    in *GREGSETP.  */
  80
  81 void
  82 supply_gregset (struct regcache* regcache,
  83                 const elf_gregset_t *gregsetp)
  84 {
  85   elf_greg_t *regp = (elf_greg_t *) gregsetp;
  86   int i;
  87
  88   for (i = 0; i < sizeof (regmap) / sizeof (regmap[0]); i++)
  89     if (regmap[i] >= 0)
  90       regcache->raw_supply (i, regp + regmap[i]);
  91 }
  92
  93 /* Fill registers in *GREGSETPS with the values in GDB's
  94    register array.  */
  95
  96 void
  97 fill_gregset (const struct regcache* regcache,
  98               elf_gregset_t *gregsetp, int regno)
  99 {
 100   elf_greg_t *regp = (elf_greg_t *) gregsetp;
 101   int i;
 102
 103   for (i = 0; i < sizeof (regmap) / sizeof (regmap[0]); i++)
 104     if (regmap[i] >= 0)
 105       regcache->raw_collect (i, regp + regmap[i]);
 106 }
 107
 108 /* Transfering floating-point registers between GDB, inferiors and cores.  */
 109
 110 /* Fill GDB's register array with the floating-point register values in
 111    *FPREGSETP.  */
 112
 113 void
 114 supply_fpregset (struct regcache *regcache,
 115                  const elf_fpregset_t *fpregsetp)
 116 {
 117   /* NOTE: There are no floating-point registers for TILE-Gx.  */
 118 }
 119
 120 /* Fill register REGNO (if it is a floating-point register) in
 121    *FPREGSETP with the value in GDB's register array.  If REGNO is -1,
 122    do this for all registers.  */
 123
 124 void
 125 fill_fpregset (const struct regcache *regcache,
 126                elf_fpregset_t *fpregsetp, int regno)
 127 {
 128   /* NOTE: There are no floating-point registers for TILE-Gx.  */
 129 }
 130
 131 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
 132    for all registers.  */
 133
 134 void
 135 tilegx_linux_nat_target::fetch_registers (struct regcache *regcache,
 136                                           int regnum)
 137 {
 138   elf_gregset_t regs;
 139   pid_t tid = get_ptrace_pid (regcache->ptid ());
 140
 141   if (ptrace (PTRACE_GETREGS, tid, 0, (PTRACE_TYPE_ARG3) &regs) < 0)
 142     perror_with_name (_("Couldn't get registers"));
 143
 144   supply_gregset (regcache, (const elf_gregset_t *)&regs);
 145 }
 146
 147 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
 148    this for all registers.  */
 149
 150 void
 151 tilegx_linux_nat_target::store_registers (struct regcache *regcache,
 152                                           int regnum)
 153 {
 154   elf_gregset_t regs;
 155   pid_t tid = get_ptrace_pid (regcache->ptid ());
 156
 157   if (ptrace (PTRACE_GETREGS, tid, 0, (PTRACE_TYPE_ARG3) &regs) < 0)
 158     perror_with_name (_("Couldn't get registers"));
 159
 160   fill_gregset (regcache, &regs, regnum);
 161
 162   if (ptrace (PTRACE_SETREGS, tid, 0, (PTRACE_TYPE_ARG3) &regs) < 0)
 163     perror_with_name (_("Couldn't write registers"));
 164 }
 165
 166 void _initialize_tile_linux_nat ();
 167 void
 168 _initialize_tile_linux_nat ()
 169 {
 170   linux_target = &the_tilegx_linux_nat_target;
 171   add_inf_child_target (&the_tilegx_linux_nat_target);
 172 }