[deliverable/binutils-gdb.git] / gdb / xtensa-linux-nat.c

/* Xtensa GNU/Linux native support.

   Copyright (C) 2007-2015 Free Software Foundation, Inc.

   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 "defs.h"
#include "frame.h"
#include "inferior.h"
#include "gdbcore.h"
#include "regcache.h"
#include "target.h"
#include "linux-nat.h"
#include <sys/types.h>
#include <signal.h>
#include <sys/user.h>
#include <sys/ioctl.h>
#include "gdb_wait.h"
#include <fcntl.h>
#include <sys/procfs.h>
#include "nat/gdb_ptrace.h"
#include <asm/ptrace.h>

#include "gregset.h"
#include "xtensa-tdep.h"

/* Extended register set depends on hardware configs.
   Keeping these definitions separately allows to introduce
   hardware-specific overlays.  */
#include "xtensa-xtregs.c"

static int
get_thread_id (ptid_t ptid)
{
  int tid = ptid_get_lwp (ptid);
  if (0 == tid)
    tid = ptid_get_pid (ptid);
  return tid;
}
#define GET_THREAD_ID(PTID)	get_thread_id (PTID)

void
fill_gregset (const struct regcache *regcache,
	      gdb_gregset_t *gregsetp, int regnum)
{
  int i;
  xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;
  struct gdbarch *gdbarch = get_regcache_arch (regcache);

  if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
    regcache_raw_collect (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
  if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
    regcache_raw_collect (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);

  if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->wb_regnum,
			  &regs->windowbase);
  if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->ws_regnum,
			  &regs->windowstart);
  if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->lbeg_regnum,
			  &regs->lbeg);
  if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->lend_regnum,
			  &regs->lend);
  if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->lcount_regnum,
			  &regs->lcount);
  if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
    regcache_raw_collect (regcache,
			  gdbarch_tdep (gdbarch)->sar_regnum,
			  &regs->sar);
  if (regnum >=gdbarch_tdep (gdbarch)->ar_base
      && regnum < gdbarch_tdep (gdbarch)->ar_base
		    + gdbarch_tdep (gdbarch)->num_aregs)
    regcache_raw_collect (regcache,regnum,
			  &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
  else if (regnum == -1)
    {
      for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
	regcache_raw_collect (regcache,
			      gdbarch_tdep (gdbarch)->ar_base + i,
			      &regs->ar[i]);
    }
}

void
supply_gregset_reg (struct regcache *regcache,
		    const gdb_gregset_t *gregsetp, int regnum)
{
  int i;
  xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;

  struct gdbarch *gdbarch = get_regcache_arch (regcache);

  if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
    regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
  if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
    regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);

  if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->wb_regnum,
			  &regs->windowbase);
  if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->ws_regnum,
			  &regs->windowstart);
  if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->lbeg_regnum,
			  &regs->lbeg);
  if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->lend_regnum,
			  &regs->lend);
  if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->lcount_regnum,
			  &regs->lcount);
  if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
    regcache_raw_supply (regcache,
			  gdbarch_tdep (gdbarch)->sar_regnum,
			  &regs->sar);
  if (regnum >=gdbarch_tdep (gdbarch)->ar_base
      && regnum < gdbarch_tdep (gdbarch)->ar_base
		    + gdbarch_tdep (gdbarch)->num_aregs)
    regcache_raw_supply (regcache,regnum,
			  &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
  else if (regnum == -1)
    {
      for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
	regcache_raw_supply (regcache,
			      gdbarch_tdep (gdbarch)->ar_base + i,
			      &regs->ar[i]);
    }
}

void
supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
{
  supply_gregset_reg (regcache, gregsetp, -1);
}

void
fill_fpregset (const struct regcache *regcache,
	       gdb_fpregset_t *fpregsetp, int regnum)
{
  return;
}

void 
supply_fpregset (struct regcache *regcache,
		 const gdb_fpregset_t *fpregsetp)
{
  return;
}

/* Fetch greg-register(s) from process/thread TID
   and store value(s) in GDB's register array.  */

static void
fetch_gregs (struct regcache *regcache, int regnum)
{
  int tid = GET_THREAD_ID (inferior_ptid);
  const gdb_gregset_t regs;
  int areg;
  
  if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
    {
      perror_with_name (_("Couldn't get registers"));
      return;
    }
 
  supply_gregset_reg (regcache, &regs, regnum);
}

/* Store greg-register(s) in GDB's register 
   array into the process/thread specified by TID.  */

static void
store_gregs (struct regcache *regcache, int regnum)
{
  int tid = GET_THREAD_ID (inferior_ptid);
  gdb_gregset_t regs;
  int areg;

  if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
    {
      perror_with_name (_("Couldn't get registers"));
      return;
    }

  fill_gregset (regcache, &regs, regnum);

  if (ptrace (PTRACE_SETREGS, tid, 0, (long) &regs) < 0)
    {
      perror_with_name (_("Couldn't write registers"));
      return;
    }
}

static int xtreg_lo;
static int xtreg_high;

/* Fetch/Store Xtensa TIE registers.  Xtensa GNU/Linux PTRACE
   interface provides special requests for this.  */

static void
fetch_xtregs (struct regcache *regcache, int regnum)
{
  int tid = GET_THREAD_ID (inferior_ptid);
  const xtensa_regtable_t *ptr;
  char xtregs [XTENSA_ELF_XTREG_SIZE];

  if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
    perror_with_name (_("Couldn't get extended registers"));

  for (ptr = xtensa_regmap_table; ptr->name; ptr++)
    if (regnum == ptr->gdb_regnum || regnum == -1)
      regcache_raw_supply (regcache, ptr->gdb_regnum,
			   xtregs + ptr->ptrace_offset);
}

static void
store_xtregs (struct regcache *regcache, int regnum)
{
  int tid = GET_THREAD_ID (inferior_ptid);
  const xtensa_regtable_t *ptr;
  char xtregs [XTENSA_ELF_XTREG_SIZE];

  if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
    perror_with_name (_("Couldn't get extended registers"));

  for (ptr = xtensa_regmap_table; ptr->name; ptr++)
    if (regnum == ptr->gdb_regnum || regnum == -1)
      regcache_raw_collect (regcache, ptr->gdb_regnum,
			    xtregs + ptr->ptrace_offset);

  if (ptrace (PTRACE_SETXTREGS, tid, 0, (long)&xtregs) < 0)
    perror_with_name (_("Couldn't write extended registers"));
}

void
xtensa_linux_fetch_inferior_registers (struct target_ops *ops,
				       struct regcache *regcache, int regnum)
{
  if (regnum == -1)
    {
      fetch_gregs (regcache, regnum);
      fetch_xtregs (regcache, regnum);
    }
  else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
    fetch_gregs (regcache, regnum);
  else
    fetch_xtregs (regcache, regnum);
}

void
xtensa_linux_store_inferior_registers (struct target_ops *ops,
				       struct regcache *regcache, int regnum)
{
  if (regnum == -1)
    {
      store_gregs (regcache, regnum);
      store_xtregs (regcache, regnum);
    }
  else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
    store_gregs (regcache, regnum);
  else
    store_xtregs (regcache, regnum);
}

void _initialize_xtensa_linux_nat (void);

void
_initialize_xtensa_linux_nat (void)
{
  struct target_ops *t;
  const xtensa_regtable_t *ptr;

  /* Calculate the number range for extended registers.  */
  xtreg_lo = 1000000000;
  xtreg_high = -1;
  for (ptr = xtensa_regmap_table; ptr->name; ptr++)
    {
      if (ptr->gdb_regnum < xtreg_lo)
	xtreg_lo = ptr->gdb_regnum;
      if (ptr->gdb_regnum > xtreg_high)
	xtreg_high = ptr->gdb_regnum;
    }

  /* Fill in the generic GNU/Linux methods.  */
  t = linux_target ();

  /* Add our register access methods.  */
  t->to_fetch_registers = xtensa_linux_fetch_inferior_registers;
  t->to_store_registers = xtensa_linux_store_inferior_registers;

  linux_nat_add_target (t);
}
Commit	Line	Data
94a0e877 MG	1	/* Xtensa GNU/Linux native support.
94a0e877 MG	2
32d0add0	3	Copyright (C) 2007-2015 Free Software Foundation, Inc.
94a0e877 MG	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"
94a0e877 MG	21	#include "frame.h"
	22	#include "inferior.h"
	23	#include "gdbcore.h"
	24	#include "regcache.h"
94a0e877 MG	25	#include "target.h"
94a0e877 MG	26	#include "linux-nat.h"
94a0e877	27	#include <sys/types.h>
94a0e877 MG	28	#include <signal.h>
	29	#include <sys/user.h>
	30	#include <sys/ioctl.h>
	31	#include "gdb_wait.h"
	32	#include <fcntl.h>
	33	#include <sys/procfs.h>
5826e159	34	#include "nat/gdb_ptrace.h"
e671835b	35	#include <asm/ptrace.h>
94a0e877 MG	36
	37	#include "gregset.h"
	38	#include "xtensa-tdep.h"
	39
	40	/* Extended register set depends on hardware configs.
	41	Keeping these definitions separately allows to introduce
	42	hardware-specific overlays. */
	43	#include "xtensa-xtregs.c"
	44
4e841acf	45	static int
94a0e877 MG	46	get_thread_id (ptid_t ptid)
94a0e877 MG	47	{
dfd4cc63	48	int tid = ptid_get_lwp (ptid);
94a0e877	49	if (0 == tid)
dfd4cc63	50	tid = ptid_get_pid (ptid);
94a0e877 MG	51	return tid;
	52	}
	53	#define GET_THREAD_ID(PTID) get_thread_id (PTID)
	54
	55	void
	56	fill_gregset (const struct regcache *regcache,
	57	gdb_gregset_t *gregsetp, int regnum)
	58	{
	59	int i;
	60	xtensa_elf_gregset_t regs = (xtensa_elf_gregset_t ) gregsetp;
	61	struct gdbarch *gdbarch = get_regcache_arch (regcache);
	62
	63	if (regnum == gdbarch_pc_regnum (gdbarch) \|\| regnum == -1)
	64	regcache_raw_collect (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
	65	if (regnum == gdbarch_ps_regnum (gdbarch) \|\| regnum == -1)
	66	regcache_raw_collect (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
	67
	68	if (regnum == gdbarch_tdep (gdbarch)->wb_regnum \|\| regnum == -1)
	69	regcache_raw_collect (regcache,
	70	gdbarch_tdep (gdbarch)->wb_regnum,
	71	&regs->windowbase);
	72	if (regnum == gdbarch_tdep (gdbarch)->ws_regnum \|\| regnum == -1)
	73	regcache_raw_collect (regcache,
	74	gdbarch_tdep (gdbarch)->ws_regnum,
	75	&regs->windowstart);
	76	if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum \|\| regnum == -1)
	77	regcache_raw_collect (regcache,
	78	gdbarch_tdep (gdbarch)->lbeg_regnum,
	79	&regs->lbeg);
	80	if (regnum == gdbarch_tdep (gdbarch)->lend_regnum \|\| regnum == -1)
	81	regcache_raw_collect (regcache,
	82	gdbarch_tdep (gdbarch)->lend_regnum,
	83	&regs->lend);
	84	if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum \|\| regnum == -1)
	85	regcache_raw_collect (regcache,
	86	gdbarch_tdep (gdbarch)->lcount_regnum,
	87	&regs->lcount);
	88	if (regnum == gdbarch_tdep (gdbarch)->sar_regnum \|\| regnum == -1)
	89	regcache_raw_collect (regcache,
	90	gdbarch_tdep (gdbarch)->sar_regnum,
	91	&regs->sar);
	92	if (regnum >=gdbarch_tdep (gdbarch)->ar_base
	93	&& regnum < gdbarch_tdep (gdbarch)->ar_base
	94	+ gdbarch_tdep (gdbarch)->num_aregs)
	95	regcache_raw_collect (regcache,regnum,
	96	&regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
	97	else if (regnum == -1)
	98	{
	99	for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
	100	regcache_raw_collect (regcache,
	101	gdbarch_tdep (gdbarch)->ar_base + i,
	102	&regs->ar[i]);
	103	}
	104	}
	105
	106	void
	107	supply_gregset_reg (struct regcache *regcache,
	108	const gdb_gregset_t *gregsetp, int regnum)
	109	{
	110	int i;
	111	xtensa_elf_gregset_t regs = (xtensa_elf_gregset_t ) gregsetp;
	112
	113	struct gdbarch *gdbarch = get_regcache_arch (regcache);
	114
115	if (regnum == gdbarch_pc_regnum (gdbarch) \|\| regnum == -1)
116	regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
117	if (regnum == gdbarch_ps_regnum (gdbarch) \|\| regnum == -1)
118	regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
119
120	if (regnum == gdbarch_tdep (gdbarch)->wb_regnum \|\| regnum == -1)
121	regcache_raw_supply (regcache,
122	gdbarch_tdep (gdbarch)->wb_regnum,
123	&regs->windowbase);
124	if (regnum == gdbarch_tdep (gdbarch)->ws_regnum \|\| regnum == -1)
125	regcache_raw_supply (regcache,
126	gdbarch_tdep (gdbarch)->ws_regnum,
127	&regs->windowstart);
128	if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum \|\| regnum == -1)
129	regcache_raw_supply (regcache,
130	gdbarch_tdep (gdbarch)->lbeg_regnum,
131	&regs->lbeg);
132	if (regnum == gdbarch_tdep (gdbarch)->lend_regnum \|\| regnum == -1)
133	regcache_raw_supply (regcache,
134	gdbarch_tdep (gdbarch)->lend_regnum,
135	&regs->lend);
136	if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum \|\| regnum == -1)
137	regcache_raw_supply (regcache,
138	gdbarch_tdep (gdbarch)->lcount_regnum,
139	&regs->lcount);
140	if (regnum == gdbarch_tdep (gdbarch)->sar_regnum \|\| regnum == -1)
141	regcache_raw_supply (regcache,
142	gdbarch_tdep (gdbarch)->sar_regnum,
143	&regs->sar);
144	if (regnum >=gdbarch_tdep (gdbarch)->ar_base
145	&& regnum < gdbarch_tdep (gdbarch)->ar_base
146	+ gdbarch_tdep (gdbarch)->num_aregs)
147	regcache_raw_supply (regcache,regnum,
148	&regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
149	else if (regnum == -1)
150	{
151	for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
152	regcache_raw_supply (regcache,
153	gdbarch_tdep (gdbarch)->ar_base + i,
154	&regs->ar[i]);
155	}
156	}
157
158	void
159	supply_gregset (struct regcache regcache, const gdb_gregset_t gregsetp)
160	{
161	supply_gregset_reg (regcache, gregsetp, -1);
162	}
163
164	void
165	fill_fpregset (const struct regcache *regcache,
166	gdb_fpregset_t *fpregsetp, int regnum)
167	{
168	return;
169	}
170
171	void
172	supply_fpregset (struct regcache *regcache,
173	const gdb_fpregset_t *fpregsetp)
174	{
175	return;
176	}
177
178	/* Fetch greg-register(s) from process/thread TID
179	and store value(s) in GDB's register array. */
180
181	static void
182	fetch_gregs (struct regcache *regcache, int regnum)
183	{
184	int tid = GET_THREAD_ID (inferior_ptid);
185	const gdb_gregset_t regs;
186	int areg;
187
188	if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
189	{
190	perror_with_name (_("Couldn't get registers"));
191	return;
192	}
193
194	supply_gregset_reg (regcache, &regs, regnum);
195	}
196
197	/* Store greg-register(s) in GDB's register
198	array into the process/thread specified by TID. */
199
200	static void
201	store_gregs (struct regcache *regcache, int regnum)
202	{
203	int tid = GET_THREAD_ID (inferior_ptid);
204	gdb_gregset_t regs;
205	int areg;
206
207	if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
208	{
209	perror_with_name (_("Couldn't get registers"));
210	return;
211	}
212
213	fill_gregset (regcache, &regs, regnum);
214
215	if (ptrace (PTRACE_SETREGS, tid, 0, (long) &regs) < 0)
216	{
217	perror_with_name (_("Couldn't write registers"));
218	return;
219	}
220	}
221
222	static int xtreg_lo;
223	static int xtreg_high;
224
225	/* Fetch/Store Xtensa TIE registers. Xtensa GNU/Linux PTRACE
226	interface provides special requests for this. */
227
228	static void
229	fetch_xtregs (struct regcache *regcache, int regnum)
230	{
231	int tid = GET_THREAD_ID (inferior_ptid);
232	const xtensa_regtable_t *ptr;
233	char xtregs [XTENSA_ELF_XTREG_SIZE];
234
235	if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
236	perror_with_name (_("Couldn't get extended registers"));
237
238	for (ptr = xtensa_regmap_table; ptr->name; ptr++)
239	if (regnum == ptr->gdb_regnum \|\| regnum == -1)
240	regcache_raw_supply (regcache, ptr->gdb_regnum,
241	xtregs + ptr->ptrace_offset);
242	}
243
244	static void
245	store_xtregs (struct regcache *regcache, int regnum)
246	{
247	int tid = GET_THREAD_ID (inferior_ptid);
248	const xtensa_regtable_t *ptr;
249	char xtregs [XTENSA_ELF_XTREG_SIZE];
250
251	if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
252	perror_with_name (_("Couldn't get extended registers"));
253
254	for (ptr = xtensa_regmap_table; ptr->name; ptr++)
255	if (regnum == ptr->gdb_regnum \|\| regnum == -1)
256	regcache_raw_collect (regcache, ptr->gdb_regnum,
257	xtregs + ptr->ptrace_offset);
258
259	if (ptrace (PTRACE_SETXTREGS, tid, 0, (long)&xtregs) < 0)
260	perror_with_name (_("Couldn't write extended registers"));
261	}
262
263	void
28439f5e PA	264	xtensa_linux_fetch_inferior_registers (struct target_ops *ops,
28439f5e PA	265	struct regcache *regcache, int regnum)
94a0e877 MG	266	{
	267	if (regnum == -1)
	268	{
	269	fetch_gregs (regcache, regnum);
	270	fetch_xtregs (regcache, regnum);
	271	}
	272	else if ((regnum < xtreg_lo) \|\| (regnum > xtreg_high))
	273	fetch_gregs (regcache, regnum);
	274	else
	275	fetch_xtregs (regcache, regnum);
	276	}
	277
	278	void
28439f5e PA	279	xtensa_linux_store_inferior_registers (struct target_ops *ops,
28439f5e PA	280	struct regcache *regcache, int regnum)
94a0e877 MG	281	{
	282	if (regnum == -1)
	283	{
	284	store_gregs (regcache, regnum);
	285	store_xtregs (regcache, regnum);
	286	}
	287	else if ((regnum < xtreg_lo) \|\| (regnum > xtreg_high))
	288	store_gregs (regcache, regnum);
	289	else
	290	store_xtregs (regcache, regnum);
	291	}
	292
	293	void _initialize_xtensa_linux_nat (void);
	294
	295	void
	296	_initialize_xtensa_linux_nat (void)
	297	{
	298	struct target_ops *t;
	299	const xtensa_regtable_t *ptr;
	300
	301	/* Calculate the number range for extended registers. */
	302	xtreg_lo = 1000000000;
	303	xtreg_high = -1;
	304	for (ptr = xtensa_regmap_table; ptr->name; ptr++)
	305	{
	306	if (ptr->gdb_regnum < xtreg_lo)
	307	xtreg_lo = ptr->gdb_regnum;
	308	if (ptr->gdb_regnum > xtreg_high)
	309	xtreg_high = ptr->gdb_regnum;
	310	}
	311
	312	/* Fill in the generic GNU/Linux methods. */
	313	t = linux_target ();
	314
	315	/* Add our register access methods. */
	316	t->to_fetch_registers = xtensa_linux_fetch_inferior_registers;
	317	t->to_store_registers = xtensa_linux_store_inferior_registers;
	318
	319	linux_nat_add_target (t);
	320	}