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+/* Motorola m68k native support for GNU/Linux.
+
+ Copyright (C) 1996-2016 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 "language.h"
+#include "gdbcore.h"
+#include "regcache.h"
+#include "target.h"
+#include "linux-nat.h"
+
+#include "m68k-tdep.h"
+
+#include <sys/dir.h>
+#include <signal.h>
+#include "nat/gdb_ptrace.h"
+#include <sys/user.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <sys/procfs.h>
+
+#ifdef HAVE_SYS_REG_H
+#include <sys/reg.h>
+#endif
+
+#include <sys/file.h>
+#include <sys/stat.h>
+
+#include "floatformat.h"
+
+/* Prototypes for supply_gregset etc. */
+#include "gregset.h"
+
+/* Defines ps_err_e, struct ps_prochandle. */
+#include "gdb_proc_service.h"
+
+#ifndef PTRACE_GET_THREAD_AREA
+#define PTRACE_GET_THREAD_AREA 25
+#endif
+
+/* This table must line up with gdbarch_register_name in "m68k-tdep.c". */
+static const int regmap[] =
+{
+ PT_D0, PT_D1, PT_D2, PT_D3, PT_D4, PT_D5, PT_D6, PT_D7,
+ PT_A0, PT_A1, PT_A2, PT_A3, PT_A4, PT_A5, PT_A6, PT_USP,
+ PT_SR, PT_PC,
+ /* PT_FP0, ..., PT_FP7 */
+ 21, 24, 27, 30, 33, 36, 39, 42,
+ /* PT_FPCR, PT_FPSR, PT_FPIAR */
+ 45, 46, 47
+};
+
+/* Which ptrace request retrieves which registers?
+ These apply to the corresponding SET requests as well. */
+#define NUM_GREGS (18)
+#define MAX_NUM_REGS (NUM_GREGS + 11)
+
+static int
+getregs_supplies (int regno)
+{
+ return 0 <= regno && regno < NUM_GREGS;
+}
+
+static int
+getfpregs_supplies (int regno)
+{
+ return M68K_FP0_REGNUM <= regno && regno <= M68K_FPI_REGNUM;
+}
+
+/* Does the current host support the GETREGS request? */
+static int have_ptrace_getregs =
+#ifdef HAVE_PTRACE_GETREGS
+ 1
+#else
+ 0
+#endif
+;
+
+
+
+/* Fetching registers directly from the U area, one at a time. */
+
+/* Fetch one register. */
+
+static void
+fetch_register (struct regcache *regcache, int regno)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ long regaddr, val;
+ int i;
+ gdb_byte buf[MAX_REGISTER_SIZE];
+ int tid;
+
+ /* Overload thread id onto process id. */
+ tid = ptid_get_lwp (inferior_ptid);
+ if (tid == 0)
+ tid = ptid_get_pid (inferior_ptid); /* no thread id, just use
+ process id. */
+
+ regaddr = 4 * regmap[regno];
+ for (i = 0; i < register_size (gdbarch, regno); i += sizeof (long))
+ {
+ errno = 0;
+ val = ptrace (PTRACE_PEEKUSER, tid, regaddr, 0);
+ memcpy (&buf[i], &val, sizeof (long));
+ regaddr += sizeof (long);
+ if (errno != 0)
+ error (_("Couldn't read register %s (#%d): %s."),
+ gdbarch_register_name (gdbarch, regno),
+ regno, safe_strerror (errno));
+ }
+ regcache_raw_supply (regcache, regno, buf);
+}
+
+/* Fetch register values from the inferior.
+ If REGNO is negative, do this for all registers.
+ Otherwise, REGNO specifies which register (so we can save time). */
+
+static void
+old_fetch_inferior_registers (struct regcache *regcache, int regno)
+{
+ if (regno >= 0)
+ {
+ fetch_register (regcache, regno);
+ }
+ else
+ {
+ for (regno = 0;
+ regno < gdbarch_num_regs (get_regcache_arch (regcache));
+ regno++)
+ {
+ fetch_register (regcache, regno);
+ }
+ }
+}
+
+/* Store one register. */
+
+static void
+store_register (const struct regcache *regcache, int regno)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ long regaddr, val;
+ int i;
+ int tid;
+ gdb_byte buf[MAX_REGISTER_SIZE];
+
+ /* Overload thread id onto process id. */
+ tid = ptid_get_lwp (inferior_ptid);
+ if (tid == 0)
+ tid = ptid_get_pid (inferior_ptid); /* no thread id, just use
+ process id. */
+
+ regaddr = 4 * regmap[regno];
+
+ /* Put the contents of regno into a local buffer. */
+ regcache_raw_collect (regcache, regno, buf);
+
+ /* Store the local buffer into the inferior a chunk at the time. */
+ for (i = 0; i < register_size (gdbarch, regno); i += sizeof (long))
+ {
+ errno = 0;
+ memcpy (&val, &buf[i], sizeof (long));
+ ptrace (PTRACE_POKEUSER, tid, regaddr, val);
+ regaddr += sizeof (long);
+ if (errno != 0)
+ error (_("Couldn't write register %s (#%d): %s."),
+ gdbarch_register_name (gdbarch, regno),
+ regno, safe_strerror (errno));
+ }
+}
+
+/* Store our register values back into the inferior.
+ If REGNO is negative, do this for all registers.
+ Otherwise, REGNO specifies which register (so we can save time). */
+
+static void
+old_store_inferior_registers (const struct regcache *regcache, int regno)
+{
+ if (regno >= 0)
+ {
+ store_register (regcache, regno);
+ }
+ else
+ {
+ for (regno = 0;
+ regno < gdbarch_num_regs (get_regcache_arch (regcache));
+ regno++)
+ {
+ store_register (regcache, regno);
+ }
+ }
+}
+
+/* Given a pointer to a general register set in /proc format
+ (elf_gregset_t *), unpack the register contents and supply
+ them as gdb's idea of the current register values. */
+
+void
+supply_gregset (struct regcache *regcache, const elf_gregset_t *gregsetp)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ const elf_greg_t *regp = (const elf_greg_t *) gregsetp;
+ int regi;
+
+ for (regi = M68K_D0_REGNUM;
+ regi <= gdbarch_sp_regnum (gdbarch);
+ regi++)
+ regcache_raw_supply (regcache, regi, &regp[regmap[regi]]);
+ regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch),
+ &regp[PT_SR]);
+ regcache_raw_supply (regcache,
+ gdbarch_pc_regnum (gdbarch), &regp[PT_PC]);
+}
+
+/* Fill register REGNO (if it is a general-purpose register) in
+ *GREGSETPS with the value in GDB's register array. If REGNO is -1,
+ do this for all registers. */
+void
+fill_gregset (const struct regcache *regcache,
+ elf_gregset_t *gregsetp, int regno)
+{
+ elf_greg_t *regp = (elf_greg_t *) gregsetp;
+ int i;
+
+ for (i = 0; i < NUM_GREGS; i++)
+ if (regno == -1 || regno == i)
+ regcache_raw_collect (regcache, i, regp + regmap[i]);
+}
+
+#ifdef HAVE_PTRACE_GETREGS
+
+/* Fetch all general-purpose registers from process/thread TID and
+ store their values in GDB's register array. */
+
+static void
+fetch_regs (struct regcache *regcache, int tid)
+{
+ elf_gregset_t regs;
+
+ if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
+ {
+ if (errno == EIO)
+ {
+ /* The kernel we're running on doesn't support the GETREGS
+ request. Reset `have_ptrace_getregs'. */
+ have_ptrace_getregs = 0;
+ return;
+ }
+
+ perror_with_name (_("Couldn't get registers"));
+ }
+
+ supply_gregset (regcache, (const elf_gregset_t *) &regs);
+}
+
+/* Store all valid general-purpose registers in GDB's register array
+ into the process/thread specified by TID. */
+
+static void
+store_regs (const struct regcache *regcache, int tid, int regno)
+{
+ elf_gregset_t regs;
+
+ if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
+ perror_with_name (_("Couldn't get registers"));
+
+ fill_gregset (regcache, &regs, regno);
+
+ if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
+ perror_with_name (_("Couldn't write registers"));
+}
+
+#else
+
+static void fetch_regs (struct regcache *regcache, int tid)
+{
+}
+
+static void store_regs (const struct regcache *regcache, int tid, int regno)
+{
+}
+
+#endif
+
+
+/* Transfering floating-point registers between GDB, inferiors and cores. */
+
+/* What is the address of fpN within the floating-point register set F? */
+#define FPREG_ADDR(f, n) (&(f)->fpregs[(n) * 3])
+
+/* Fill GDB's register array with the floating-point register values in
+ *FPREGSETP. */
+
+void
+supply_fpregset (struct regcache *regcache, const elf_fpregset_t *fpregsetp)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ int regi;
+
+ for (regi = gdbarch_fp0_regnum (gdbarch);
+ regi < gdbarch_fp0_regnum (gdbarch) + 8; regi++)
+ regcache_raw_supply (regcache, regi,
+ FPREG_ADDR (fpregsetp,
+ regi - gdbarch_fp0_regnum (gdbarch)));
+ regcache_raw_supply (regcache, M68K_FPC_REGNUM, &fpregsetp->fpcntl[0]);
+ regcache_raw_supply (regcache, M68K_FPS_REGNUM, &fpregsetp->fpcntl[1]);
+ regcache_raw_supply (regcache, M68K_FPI_REGNUM, &fpregsetp->fpcntl[2]);
+}
+
+/* Fill register REGNO (if it is a floating-point register) in
+ *FPREGSETP with the value in GDB's register array. If REGNO is -1,
+ do this for all registers. */
+
+void
+fill_fpregset (const struct regcache *regcache,
+ elf_fpregset_t *fpregsetp, int regno)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ int i;
+
+ /* Fill in the floating-point registers. */
+ for (i = gdbarch_fp0_regnum (gdbarch);
+ i < gdbarch_fp0_regnum (gdbarch) + 8; i++)
+ if (regno == -1 || regno == i)
+ regcache_raw_collect (regcache, i,
+ FPREG_ADDR (fpregsetp,
+ i - gdbarch_fp0_regnum (gdbarch)));
+
+ /* Fill in the floating-point control registers. */
+ for (i = M68K_FPC_REGNUM; i <= M68K_FPI_REGNUM; i++)
+ if (regno == -1 || regno == i)
+ regcache_raw_collect (regcache, i,
+ &fpregsetp->fpcntl[i - M68K_FPC_REGNUM]);
+}
+
+#ifdef HAVE_PTRACE_GETREGS
+
+/* Fetch all floating-point registers from process/thread TID and store
+ thier values in GDB's register array. */
+
+static void
+fetch_fpregs (struct regcache *regcache, int tid)
+{
+ elf_fpregset_t fpregs;
+
+ if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name (_("Couldn't get floating point status"));
+
+ supply_fpregset (regcache, (const elf_fpregset_t *) &fpregs);
+}
+
+/* Store all valid floating-point registers in GDB's register array
+ into the process/thread specified by TID. */
+
+static void
+store_fpregs (const struct regcache *regcache, int tid, int regno)
+{
+ elf_fpregset_t fpregs;
+
+ if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name (_("Couldn't get floating point status"));
+
+ fill_fpregset (regcache, &fpregs, regno);
+
+ if (ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name (_("Couldn't write floating point status"));
+}
+
+#else
+
+static void fetch_fpregs (struct regcache *regcache, int tid)
+{
+}
+
+static void store_fpregs (const struct regcache *regcache, int tid, int regno)
+{
+}
+
+#endif
+
+/* Transferring arbitrary registers between GDB and inferior. */
+
+/* Fetch register REGNO from the child process. If REGNO is -1, do
+ this for all registers (including the floating point and SSE
+ registers). */
+
+static void
+m68k_linux_fetch_inferior_registers (struct target_ops *ops,
+ struct regcache *regcache, int regno)
+{
+ int tid;
+
+ /* Use the old method of peeking around in `struct user' if the
+ GETREGS request isn't available. */
+ if (! have_ptrace_getregs)
+ {
+ old_fetch_inferior_registers (regcache, regno);
+ return;
+ }
+
+ /* GNU/Linux LWP ID's are process ID's. */
+ tid = ptid_get_lwp (inferior_ptid);
+ if (tid == 0)
+ tid = ptid_get_pid (inferior_ptid); /* Not a threaded program. */
+
+ /* Use the PTRACE_GETFPXREGS request whenever possible, since it
+ transfers more registers in one system call, and we'll cache the
+ results. But remember that fetch_fpxregs can fail, and return
+ zero. */
+ if (regno == -1)
+ {
+ fetch_regs (regcache, tid);
+
+ /* The call above might reset `have_ptrace_getregs'. */
+ if (! have_ptrace_getregs)
+ {
+ old_fetch_inferior_registers (regcache, -1);
+ return;
+ }
+
+ fetch_fpregs (regcache, tid);
+ return;
+ }
+
+ if (getregs_supplies (regno))
+ {
+ fetch_regs (regcache, tid);
+ return;
+ }
+
+ if (getfpregs_supplies (regno))
+ {
+ fetch_fpregs (regcache, tid);
+ return;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("Got request for bad register number %d."), regno);
+}
+
+/* Store register REGNO back into the child process. If REGNO is -1,
+ do this for all registers (including the floating point and SSE
+ registers). */
+static void
+m68k_linux_store_inferior_registers (struct target_ops *ops,
+ struct regcache *regcache, int regno)
+{
+ int tid;
+
+ /* Use the old method of poking around in `struct user' if the
+ SETREGS request isn't available. */
+ if (! have_ptrace_getregs)
+ {
+ old_store_inferior_registers (regcache, regno);
+ return;
+ }
+
+ /* GNU/Linux LWP ID's are process ID's. */
+ tid = ptid_get_lwp (inferior_ptid);
+ if (tid == 0)
+ tid = ptid_get_pid (inferior_ptid); /* Not a threaded program. */
+
+ /* Use the PTRACE_SETFPREGS requests whenever possible, since it
+ transfers more registers in one system call. But remember that
+ store_fpregs can fail, and return zero. */
+ if (regno == -1)
+ {
+ store_regs (regcache, tid, regno);
+ store_fpregs (regcache, tid, regno);
+ return;
+ }
+
+ if (getregs_supplies (regno))
+ {
+ store_regs (regcache, tid, regno);
+ return;
+ }
+
+ if (getfpregs_supplies (regno))
+ {
+ store_fpregs (regcache, tid, regno);
+ return;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("Got request to store bad register number %d."), regno);
+}
+
+
+/* Fetch the thread-local storage pointer for libthread_db. */
+
+ps_err_e
+ps_get_thread_area (struct ps_prochandle *ph,
+ lwpid_t lwpid, int idx, void **base)
+{
+ if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) < 0)
+ return PS_ERR;
+
+ /* IDX is the bias from the thread pointer to the beginning of the
+ thread descriptor. It has to be subtracted due to implementation
+ quirks in libthread_db. */
+ *base = (char *) *base - idx;
+
+ return PS_OK;
+}
+
+
+void _initialize_m68k_linux_nat (void);
+
+void
+_initialize_m68k_linux_nat (void)
+{
+ struct target_ops *t;
+
+ /* Fill in the generic GNU/Linux methods. */
+ t = linux_target ();
+
+ /* Add our register access methods. */
+ t->to_fetch_registers = m68k_linux_fetch_inferior_registers;
+ t->to_store_registers = m68k_linux_store_inferior_registers;
+
+ /* Register the target. */
+ linux_nat_add_target (t);
+}