Fw: Unreviewed patch (m32r-linux support)

["Kei Sakamoto" <sakamoto.kei@renesas.com>]

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Mark,

Would you review the attached patch?
I'm afraid that you are still busy because of moving.
But it seems you are the best person to review it
because I revised it based on your advise.
If you are too busy, please let me know.
Thank you.

Kei Sakamoto


> Hello,
>
> Would anyone take a look at this patch?
> Thank you in advance.
>
> Kei Sakamoto
>
> From: "Kei Sakamoto" <sakamoto.kei@renesas.com>
> To: <gdb-patches@sources.redhat.com>
> Sent: Friday, August 20, 2004 3:14 PM
> Subject: Re: [RFA/m32r] m32r-linux support
>
>
> > Hello,
> >
> > I revised the patch of m32r-linux support.
> >
> > Thanks to Mark Kettenis' advice, I removed many unnecessary codes
> > from it and simplified it. But it still contains some stuff
> > to support older versions of Linux because Linux/M32R does not
> > support PTRACE_GETREGS.
> >
> > I also removed the gdbserver support from it. I'll post it
> > as another patch after this patch is accepted.
> >
> > OK to commit?
> >
> > 2004-08-20    Kei Sakamoto  <sakamoto.kei@renesas.com>
> >
> >     Add m32r-linux support.
> >     * configure.tgt: Add m32r*-*-linux*.
> >     * Makefile.in (ALLDEPFILES): Add m32r-tdep.c, m32r-linux-nat.c and
> >     m32r-linux-tdep.c.
> >     (m32r-linux-nat.o, m32r-linux-tdep.o): New dependencies.
> >     * m32r-linux-nat.c, m32r-linux-tdep.c, config/m32r/linux.mh,
> >     config/m32r/linux.mt, config/m32r/m32r.mh, config/m32r/nm-linux.h,
> >     config/m32r/tm-linux.h: New files.
> >
> > Kei Sakamoto said:
> >
> > > Hello, Mark,
> > >
> > > Thank you for your reply. It is very useful.
> > >
> > > There is the summer holidays in Japan next week. So I'll modify my
> > > patch and post it after that.
> > >
> > > Kei Sakamoto
> > >
> > > Mark Kettenis said:
> > > >    From: "Kei Sakamoto" <sakamoto.kei@renesas.com>
> > > >    Date: Thu, 5 Aug 2004 14:11:07 +0900
> > > >
> > > >    Hello,
> > > >
> > > > Hi Kei,
> > > >
> > > > First can you seperate out the gdbserver support, and submit that as a
> > > > seperate patch?  Daniel will have to review that part of the code.
> > > > Making it seperate will make it more likely that the code can be
> > > > checked in soon.
> > > >
> > > >    The attached patch adds m32r-linux support.
> > > >    The M32R architecture is not added to the official Linux kernel yet.
> > > >    But Linux on M32R is already available.
> > > >    http://www.linux-m32r.org/
> > > >
> > > > So Linux/M32R is a brand new port?  Great, but in that case I have
> > > > some comments.  It looks like you based your GDB port on the
> > > > Linux/i386 stuff.  That's great, but you must realize that part of the
> > > > i386 code that you copied and modified is only there to support older
> > > > versions of Linux.  I hope it isn't necessary for Linux/M32R and would
> > > > like you to remove it before this gets committed.  I've got a few
> > > > other comments too.  Here we go...
> > > >
> > > >    diff -u -r1.144 configure.tgt=0A=
> > > >    --- configure.tgt 26 Jun 2004 10:06:34 -0000 1.144=0A=
> > > >    +++ configure.tgt 5 Aug 2004 04:48:33 -0000=0A=
> > > >    @@ -102,7 +103,10 @@
> > > >    ;;
> > > >     ia64*-*-*) gdb_target=ia64 ;;
> > > >
> > > >    -m32r-*-*) gdb_target=m32r ;;
> > > >    +m32r*-*-elf*) gdb_target=m32r ;;
> > > >    +m32r*-*-linux*) gdb_target=linux
> > > >    + build_gdbserver=3Dyes
> > > >    + ;;
> > > >
> > > >     m68hc11*-*-*|m6811*-*-*) gdb_target=m68hc11 ;;
> > > >
> > > > It might be a good idea to keep m32r-*-* as the generic M32R target.
> > > > Just put the m32r-*-* entry in front of it.
> > > >
> > > >    diff -N m32r-linux-nat.c
> > > >    --- /dev/null 1 Jan 1970 00:00:00 -0000
> > > >    +++ m32r-linux-nat.c 5 Aug 2004 04:48:33 -0000
> > > >    +/* The register sets used in GNU/Linux ELF core-dumps are identical
to
> > > >    +   the register sets in `struct user' that is used for a.out
> > > >    +   core-dumps, and is also used by `ptrace'.  The corresponding
types
> > > >    +   are `elf_gregset_t' for the general-purpose registers (with
> > > >    +   `elf_greg_t' the type of a single GP register) and
`elf_fpregset_t'
> > > >    +   for the floating-point registers.
> > > >    +
> > > >    +   Those types used to be available under the names `gregset_t' and
> > > >    +   `fpregset_t' too, and this file used those names in the past.
But
> > > >    +   those names are now used for the register sets used in the
> > > >    +   `mcontext_t' type, and have a different size and layout.  */
> > > >    +
> > > >    +/* Mapping between the general-purpose registers in `struct user'
> > > >    +   format and GDB's register array layout.  */
> > > >    +static int regmap[] = {
> > > >    +  4, 5, 6, 7, 0, 1, 2, 8,
> > > >    +  9, 10, 11, 12, 13, 24, 25, 23,
> > > >    +  19, 31, 26, 23, 20, 30, 16, 15,
> > > >    +  32
> > > >    +};
> > > >
> > > > Does Linux/M32R support a.out?  That would really surprise me.  So I
> > > > don't think you need this stuff.
> > > >
> > > >    +#define M32R_NUM_GREGS 25=0A=
> > > >
> > > > I think that one really belongs in m32r-tdep.h.
> > > >
> > > >    +/* Doee apply to the corresponding SET requests as well.  *
> > > >    +#define GETREGS_SUPPLIES(regno) (0 <=3D (regno) && (regno) <=
> > > M32R_NUM_GREGS)
> > > >    +#define GETFPREGS_SUPPLIES(regno) 0
> > > >
> > > > Does the M32R support floating point registers at all?  If not, you
> > > > could rip out all the FPREGS stuff.
> > > >
> > > >    +/* Does the current host support the GETREGS request?  */
> > > >    +int have_ptrace_getregs =
> > > >    +#ifdef HAVE_PTRACE_GETREGS
> > > >    +  1
> > > >    +#else
> > > >    +  0
> > > >    +#endif
> > > >    +  ;
> > > >
> > > > I really hope that all released M32R kernels support the
> > > > PTRACE_GETREGS request.  In that case this should not be necessary.
> > > >
> > > >
> > > >    +/* Support for the user struct.  */
> > > >    +
> > > >    +/* Return the address of register REGNUM.  BLOCKEND is the value of
> > > >    +   u.u_ar0, which should point to the registers.  */
> > > >    +
> > > >    +CORE_ADDR
> > > >    +register_u_addr (CORE_ADDR blockend, int regnum)
> > > >    +{
> > > >    +  return (blockend + 4 * regmap[regnum]);
> > > >    +}
> > > >    +
> > > >    +/* Return the size of the user struct.  */
> > > >    +
> > > >    +int
> > > >    +kernel_u_size (void)
> > > >    +{
> > > >    +  return (sizeof (struct user));
> > > >    +}
> > > >
> > > > The `user struct' is a wart from ancient UNIX.  There really is no
> > > > point in supporting it on modern versions of Linux.  If Linux/M32R is
> > > > ELF-only and fully supports PTRACE_GETREGS, this can go too.
> > > >
> > > >    +#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 (int tid)
> > > >    +{
> > > >    +  elf_gregset_t regs;
> > > >    +
> > > >
> > > > This code in #ifdef HAVE_PTRACE_GETREGS can be simplified considerably
> > > > if you assume that PTRACE_GETREGS works.  Move the code to
> > > > fetch_inferior_registers() and store_inferior_registers() below.
> > > >
> > > >    +/* Transferring arbitrary registers between GDB and inferior.  */
> > > >    +
> > > >    +/* Check if register REGNO in the child process is accessible.
> > > >    +   If we are accessing registers directly via the U area, only the
> > > >    +   general-purpose registers are available.
> > > >    +   All registers should be accessible if we have GETREGS support.
*/
> > > >    +
> > > >    +int
> > > >    +cannot_fetch_register (int regno)
> > > >    +{
> > > >    +  gdb_assert (regno >= 0 && regno < NUM_REGS);
> > > >    +  return (!have_ptrace_getregs && regmap[regno] == -1);
> > > >    +}
> > > >    +
> > > >    +int
> > > >    +cannot_store_register (int regno)
> > > >    +{
> > > >    +  gdb_assert (regno >= 0 && regno < NUM_REGS);
> > > >    +  return (!have_ptrace_getregs && regmap[regno] == -1);
> > > >    +}
> > > >
> > > > These functions should no longer be necessary.
> > > >
> > > >    +/* Accessing registers through the U area, one at a time.  */
> > > >    +
> > > >    +/* Fetch one register.  */
> > > >    +
> > > >    +static void
> > > >    +fetch_register (int regno)
> > > >    +{
> > > >    +  int tid;
> > > >    +  int val;
> > > >    +
> > > >    +  gdb_assert (!have_ptrace_getregs);
> > > >    +  if (cannot_fetch_register (regno))
> > > >    +    {
> > > >    +      regcache_raw_supply (current_regcache, regno, NULL);
> > > >    +      return;
> > > >    +    }=
> > > >
> > > > This can go too; no U area anymore :-).
> > > >
> > > >    diff -N config/m32r/linux.mh
> > > >    --- /dev/null 1 Jan 1970 00:00:00 -0000
> > > >    +++ config/m32r/linux.mh 5 Aug 2004 04:48:34 -0000
> > > >    @@ -0,0 +1,9 @@
> > > >    +# Host: M32R based machine running GNU/Linux
> > > >    +
> > > >    +NAT_FILE= nm-linux.h
> > > >    +NATDEPFILES= infptrace.o inftarg.o fork-child.o corelow.o \
> > > >    + core-aout.o m32r-linux-nat.o linux-proc.o gcore.o \
> > > >    + proc-service.o thread-db.o lin-lwp.o linux-nat.o
> > > >    +
> > > >    +LOADLIBES=3D -ldl -rdynamic
> > > >
> > > > core-aout.o shouldn't be necessary.
> > > >
> > > >    diff -N config/m32r/m32r.mh
> > > >
> > > > Please remove this file.
> > > >
> > > >    diff -u -r1.7 m32r.mt
> > > >    --- config/m32r/m32r.mt 16 Oct 2003 02:36:39 -0000 1.7
> > > >    +++ config/m32r/m32r.mt 5 Aug 2004 04:48:34 -0000
> > > >    @@ -1,4 +1,5 @@
> > > >     # Target: Renesas m32r processor
> > > >     TDEPFILES= m32r-tdep.o monitor.o m32r-rom.o dsrec.o
remote-m32r-sdi.o
> > > >    +TM_FILE= tm-m32r.h
> > > >     SIM_OBS = remote-sim.o
> > > >     SIM = ../sim/m32r/libsim.a
> > > >
> > > > This shouldn't be necessary.  See below.
> > > >
> > > >    diff -N config/m32r/nm-linux.h
> > > >    --- /dev/null 1 Jan 1970 00:00:00 -0000
> > > >    +++ config/m32r/nm-linux.h 5 Aug 2004 04:48:34 -0000
> > > >
> > > >    [snip]
> > > >
> > > >    +/* Support for the user area.  */
> > > >    +
> > > >    +/* Return the size of the user struct.  */
> > > >    +extern int kernel_u_size (void);
> > > >    +#define KERNEL_U_SIZE kernel_u_size()
> > > >    +
> > > >    +/* This is the amount to subtract from u.u_ar0
> > > >    +   to get the offset in the core file of the register values.  */
> > > >    +#define KERNEL_U_ADDR 0x0
> > > >    +
> > > >    +/* Offset of the registers within the user area.  */
> > > >    +#define U_REGS_OFFSET 0
> > > >    +
> > > >    +extern CORE_ADDR register_u_addr (CORE_ADDR blockend, int regnum);
> > > >    +#define REGISTER_U_ADDR(addr, blockend, regnum) \
> > > >    +  (addr) = register_u_addr (blockend, regnum)
> > > >
> > > > This user area stuff can go too.
> > > >
> > > >    diff -N config/m32r/tm-m32r.h
> > > >
> > > > This file contains nothing useful.  Please remove and adjust tm-linux.h.
> > > >
> > > > I hope you can make the changes.  The simplifications will make
> > > > maintaining the code much easier.
> >
>

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Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.608
diff -u -r1.608 Makefile.in
--- Makefile.in	14 Aug 2004 20:40:14 -0000	1.608
+++ Makefile.in	20 Aug 2004 05:54:29 -0000
@@ -1373,6 +1373,8 @@
 	infptrace.c inftarg.c irix4-nat.c irix5-nat.c \
 	libunwind-frame.c \
 	lynx-nat.c m3-nat.c \
+	m32r-tdep.c \
+	m32r-linux-tdep.c m32r-linux-nat.c \
 	m68hc11-tdep.c \
 	m68k-tdep.c \
 	m68kbsd-nat.c m68kbsd-tdep.c \
@@ -2114,6 +2116,11 @@
 	$(expression_h) $(value_h) $(gdbcore_h) $(target_h) $(m2_lang_h)
 m2-valprint.o: m2-valprint.c $(defs_h) $(symtab_h) $(gdbtypes_h) \
 	$(m2_lang_h)
+m32r-linux-nat.o: m32r-linux-nat.c $(defs_h) $(inferior_h) $(gdbcore_h) \
+	$(regcache_h) $(linux_nat_h) $(gdb_assert_h) $(gdb_string_h)
+m32r-linux-tdep.o: m32r-linux-tdep.c $(defs_h) $(gdbcore_h) $(frame_h) \
+	$(value_h) $(regcache_h) $(inferior_h) $(osabi_h) $(reggroups_h) \
+	$(gdb_string_h) $(glibc_tdep_h) $(solib_svr4_h)
 m32r-rom.o: m32r-rom.c $(defs_h) $(gdbcore_h) $(target_h) $(monitor_h) \
 	$(serial_h) $(symtab_h) $(command_h) $(gdbcmd_h) $(symfile_h) \
 	$(gdb_string_h) $(objfiles_h) $(inferior_h) $(regcache_h)
Index: configure.tgt
===================================================================
RCS file: /cvs/src/src/gdb/configure.tgt,v
retrieving revision 1.146
diff -u -r1.146 configure.tgt
--- configure.tgt	12 Aug 2004 22:29:56 -0000	1.146
+++ configure.tgt	20 Aug 2004 05:54:29 -0000
@@ -106,7 +106,8 @@
 			;;
 ia64*-*-*)		gdb_target=ia64 ;;
 
-m32r-*-*)		gdb_target=m32r ;;
+m32r*-*-linux*)         gdb_target=linux ;;
+m32r*-*-*)		gdb_target=m32r ;;
 
 m68hc11*-*-*|m6811*-*-*)	gdb_target=m68hc11 ;;
 
Index: m32r-linux-nat.c
===================================================================
RCS file: m32r-linux-nat.c
diff -N m32r-linux-nat.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ m32r-linux-nat.c	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,345 @@
+/* Native-dependent code for GNU/Linux m32r.
+
+   Copyright 2004 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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "inferior.h"
+#include "gdbcore.h"
+#include "regcache.h"
+#include "linux-nat.h"
+
+#include "gdb_assert.h"
+#include "gdb_string.h"
+#include <sys/ptrace.h>
+#include <sys/user.h>
+#include <sys/procfs.h>
+
+/* Prototypes for supply_gregset etc.  */
+#include "gregset.h"
+\f
+
+
+/* The register sets used in GNU/Linux ELF core-dumps are identical to
+   the register sets in `struct user' that is used by `ptrace'.  The
+   corresponding types are `elf_gregset_t' for the general-purpose
+   registers (with `elf_greg_t' the type of a single GP register) and
+   `elf_fpregset_t' for the floating-point registers.
+
+   Those types used to be available under the names `gregset_t' and
+   `fpregset_t' too, and this file used those names in the past.  But
+   those names are now used for the register sets used in the
+   `mcontext_t' type, and have a different size and layout.  */
+
+/* Mapping between the general-purpose registers in `struct user'
+   format and GDB's register array layout.  */
+static int regmap[] = {
+  4, 5, 6, 7, 0, 1, 2, 8,
+  9, 10, 11, 12, 13, 24, 25, 23,
+  19, 31, 26, 23, 20, 30, 16, 15,
+  32
+};
+
+/* Doee apply to the corresponding SET requests as well.  */
+#define GETREGS_SUPPLIES(regno) (0 <= (regno) && (regno) <= NUM_REGS)
+
+/* Does the current host support the GETREGS request?  */
+int have_ptrace_getregs =
+#ifdef HAVE_PTRACE_GETREGS
+  1
+#else
+  0
+#endif
+  ;
+\f
+
+/* Transfering the general-purpose registers between GDB, inferiors
+   and core files.  */
+
+/* Fill GDB's register array with the general-purpose register values
+   in *GREGSETP.  */
+
+void
+supply_gregset (elf_gregset_t * gregsetp)
+{
+  elf_greg_t *regp = (elf_greg_t *) gregsetp;
+  int i;
+
+  for (i = 0; i < NUM_REGS; i++)
+    regcache_raw_supply (current_regcache, i, regp + regmap[i]);
+}
+
+/* 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 (elf_gregset_t * gregsetp, int regno)
+{
+  elf_greg_t *regp = (elf_greg_t *) gregsetp;
+  int i;
+
+  for (i = 0; i < NUM_REGS; i++)
+    if (regno == -1 || regno == i)
+      regcache_raw_collect (current_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 (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 (&regs);
+}
+
+/* Store all valid general-purpose registers in GDB's register array
+   into the process/thread specified by TID.  */
+
+static void
+store_regs (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 (&regs, regno);
+
+  if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
+    perror_with_name ("Couldn't write registers");
+}
+
+#else
+
+static void
+fetch_regs (int tid)
+{
+}
+static void
+store_regs (int tid, int regno)
+{
+}
+
+#endif
+\f
+
+/* Transfering floating-point registers between GDB, inferiors and cores.  */
+
+/* Fill GDB's register array with the floating-point register values in
+   *FPREGSETP.  */
+
+void
+supply_fpregset (elf_fpregset_t * fpregsetp)
+{
+}
+
+/* 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 (elf_fpregset_t * fpregsetp, int regno)
+{
+}
+
+\f
+
+/* Transferring arbitrary registers between GDB and inferior.  */
+
+/* Check if register REGNO in the child process is accessible.
+   If we are accessing registers directly via the U area, only the
+   general-purpose registers are available.
+   All registers should be accessible if we have GETREGS support.  */
+
+int
+cannot_fetch_register (int regno)
+{
+  gdb_assert (regno >= 0 && regno < NUM_REGS);
+  return (!have_ptrace_getregs && regmap[regno] == -1);
+}
+
+int
+cannot_store_register (int regno)
+{
+  gdb_assert (regno >= 0 && regno < NUM_REGS);
+  return (!have_ptrace_getregs && regmap[regno] == -1);
+}
+
+/* Accessing registers through the U area, one at a time.  */
+
+/* Fetch one register.  */
+
+static void
+fetch_register (int regno)
+{
+  int tid;
+  int val;
+
+  gdb_assert (!have_ptrace_getregs);
+  if (cannot_fetch_register (regno))
+    {
+      regcache_raw_supply (current_regcache, regno, NULL);
+      return;
+    }
+
+  /* GNU/Linux LWP ID's are process ID's.  */
+  tid = TIDGET (inferior_ptid);
+  if (tid == 0)
+    tid = PIDGET (inferior_ptid);	/* Not a threaded program.  */
+
+  errno = 0;
+  val = ptrace (PTRACE_PEEKUSER, tid, 4 * regmap[regno], 0);
+  if (errno != 0)
+    error ("Couldn't read register %s (#%d): %s.", REGISTER_NAME (regno),
+	   regno, safe_strerror (errno));
+
+  regcache_raw_supply (current_regcache, regno, &val);
+}
+
+/* Store one register. */
+
+static void
+store_register (int regno)
+{
+  int tid;
+  int val;
+
+  gdb_assert (!have_ptrace_getregs);
+  if (cannot_store_register (regno))
+    return;
+
+  /* GNU/Linux LWP ID's are process ID's.  */
+  tid = TIDGET (inferior_ptid);
+  if (tid == 0)
+    tid = PIDGET (inferior_ptid);	/* Not a threaded program.  */
+
+  errno = 0;
+  regcache_raw_collect (current_regcache, regno, &val);
+  ptrace (PTRACE_POKEUSER, tid, 4 * regmap[regno], val);
+  if (errno != 0)
+    error ("Couldn't write register %s (#%d): %s.", REGISTER_NAME (regno),
+	   regno, safe_strerror (errno));
+}
+
+/* Fetch register REGNO from the child process.  If REGNO is -1, do
+   this for all registers (including the floating point and SSE
+   registers).  */
+
+void
+fetch_inferior_registers (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)
+    {
+      int i;
+
+      for (i = 0; i < NUM_REGS; i++)
+	if (regno == -1 || regno == i)
+	  fetch_register (i);
+
+      return;
+    }
+
+  /* GNU/Linux LWP ID's are process ID's.  */
+  tid = TIDGET (inferior_ptid);
+  if (tid == 0)
+    tid = PIDGET (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.  */
+  if (regno == -1)
+    {
+      fetch_regs (tid);
+
+      /* The call above might reset `have_ptrace_getregs'.  */
+      if (!have_ptrace_getregs)
+	{
+	  fetch_inferior_registers (regno);
+	  return;
+	}
+
+      return;
+    }
+
+  if (GETREGS_SUPPLIES (regno))
+    {
+      fetch_regs (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).  */
+void
+store_inferior_registers (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)
+    {
+      int i;
+
+      for (i = 0; i < NUM_REGS; i++)
+	if (regno == -1 || regno == i)
+	  store_register (i);
+
+      return;
+    }
+
+  /* GNU/Linux LWP ID's are process ID's.  */
+  if ((tid = TIDGET (inferior_ptid)) == 0)
+    tid = PIDGET (inferior_ptid);	/* Not a threaded program.  */
+
+  if (regno == -1 || GETREGS_SUPPLIES (regno))
+    {
+      store_regs (tid, regno);
+      return;
+    }
+
+  internal_error (__FILE__, __LINE__,
+		  "Got request to store bad register number %d.", regno);
+}
Index: m32r-linux-tdep.c
===================================================================
RCS file: m32r-linux-tdep.c
diff -N m32r-linux-tdep.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ m32r-linux-tdep.c	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,334 @@
+/* Target-dependent code for GNU/Linux m32r.
+
+   Copyright 2004 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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "gdbcore.h"
+#include "frame.h"
+#include "value.h"
+#include "regcache.h"
+#include "inferior.h"
+#include "osabi.h"
+#include "reggroups.h"
+
+#include "gdb_string.h"
+
+#include "glibc-tdep.h"
+#include "solib-svr4.h"
+
+#include "trad-frame.h"
+#include "frame-unwind.h"
+\f
+
+/* Recognizing signal handler frames.  */
+
+/* GNU/Linux has two flavors of signals.  Normal signal handlers, and
+   "realtime" (RT) signals.  The RT signals can provide additional
+   information to the signal handler if the SA_SIGINFO flag is set
+   when establishing a signal handler using `sigaction'.  It is not
+   unlikely that future versions of GNU/Linux will support SA_SIGINFO
+   for normal signals too.  */
+
+/* When the m32r Linux kernel calls a signal handler and the
+   SA_RESTORER flag isn't set, the return address points to a bit of
+   code on the stack.  This function returns whether the PC appears to
+   be within this bit of code.
+
+   The instruction sequence for normal signals is
+       ldi    r7, #__NR_sigreturn
+       trap   #2
+   or 0x67 0x77 0x10 0xf2.
+
+   Checking for the code sequence should be somewhat reliable, because
+   the effect is to call the system call sigreturn.  This is unlikely
+   to occur anywhere other than in a signal trampoline.
+
+   It kind of sucks that we have to read memory from the process in
+   order to identify a signal trampoline, but there doesn't seem to be
+   any other way.  Therefore we only do the memory reads if no
+   function name could be identified, which should be the case since
+   the code is on the stack.
+
+   Detection of signal trampolines for handlers that set the
+   SA_RESTORER flag is in general not possible.  Unfortunately this is
+   what the GNU C Library has been doing for quite some time now.
+   However, as of version 2.1.2, the GNU C Library uses signal
+   trampolines (named __restore and __restore_rt) that are identical
+   to the ones used by the kernel.  Therefore, these trampolines are
+   supported too.  */
+
+/* If PC is in a sigtramp routine, return the address of the start of
+   the routine.  Otherwise, return 0.  */
+
+static CORE_ADDR
+m32r_linux_sigtramp_start (CORE_ADDR pc)
+{
+  /* We only recognize a signal trampoline if PC is at the start of
+     one of the instructions.  We optimize for finding the PC at the
+     start of the instruction sequence, as will be the case when the
+     trampoline is not the first frame on the stack.  We assume that
+     in the case where the PC is not at the start of the instruction
+     sequence, there will be a few trailing readable bytes on the
+     stack.  */
+
+  if (pc % 2 != 0)
+    {
+      if (read_memory_unsigned_integer (pc, 2) == 0x10f2)
+	pc -= 2;
+      else
+	return 0;
+    }
+
+  if (read_memory_unsigned_integer (pc, 4) != 0x677710f2)
+    return 0;
+
+  return pc;
+}
+
+/* This function does the same for RT signals.  Here the instruction
+   sequence is
+       ldi    r7, #__NR_rt_sigreturn
+       trap   #2
+   or 0x97 0xf0 0x00 0xad 0x10 0xf2 0xf0 0x00.
+
+   The effect is to call the system call rt_sigreturn.  */
+
+/* If PC is in a RT sigtramp routine, return the address of the start
+   of the routine.  Otherwise, return 0.  */
+
+static CORE_ADDR
+m32r_linux_rt_sigtramp_start (CORE_ADDR pc)
+{
+  /* We only recognize a signal trampoline if PC is at the start of
+     one of the instructions.  We optimize for finding the PC at the
+     start of the instruction sequence, as will be the case when the
+     trampoline is not the first frame on the stack.  We assume that
+     in the case where the PC is not at the start of the instruction
+     sequence, there will be a few trailing readable bytes on the
+     stack.  */
+
+  if (pc % 2 != 0)
+    return 0;
+
+  switch (read_memory_unsigned_integer (pc, 4))
+    {
+    case 0x97f000ad:
+      if (read_memory_unsigned_integer (pc + 4, 4) == 0x10f2f000)
+	return pc;
+      break;
+    case 0x10f2f000:
+      if (read_memory_unsigned_integer (pc - 4, 4) == 0x97f000ad)
+	return pc - 4;
+      break;
+    }
+
+  return 0;
+}
+
+static int
+m32r_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
+{
+  /* If we have NAME, we can optimize the search.  The trampolines are
+     named __restore and __restore_rt.  However, they aren't dynamically
+     exported from the shared C library, so the trampoline may appear to
+     be part of the preceding function.  This should always be sigaction,
+     __sigaction, or __libc_sigaction (all aliases to the same function).  */
+  if (name == NULL || strstr (name, "sigaction") != NULL)
+    return (m32r_linux_sigtramp_start (pc) != 0
+	    || m32r_linux_rt_sigtramp_start (pc) != 0);
+
+  return (strcmp ("__restore", name) == 0
+	  || strcmp ("__restore_rt", name) == 0);
+}
+
+/* From <asm/sigcontext.h>.  */
+static int m32r_linux_sc_reg_offset[] = {
+  4 * 4,			/* r0 */
+  5 * 4,			/* r1 */
+  6 * 4,			/* r2 */
+  7 * 4,			/* r3 */
+  0 * 4,			/* r4 */
+  1 * 4,			/* r5 */
+  2 * 4,			/* r6 */
+  8 * 4,			/* r7 */
+  9 * 4,			/* r8 */
+  10 * 4,			/* r9 */
+  11 * 4,			/* r10 */
+  12 * 4,			/* r11 */
+  13 * 4,			/* r12 */
+  21 * 4,			/* fp */
+  22 * 4,			/* lr */
+  -1 * 4,			/* sp */
+  16 * 4,			/* psw */
+  -1 * 4,			/* cbr */
+  23 * 4,			/* spi */
+  20 * 4,			/* spu */
+  19 * 4,			/* bpc */
+  17 * 4,			/* pc */
+  15 * 4,			/* accl */
+  14 * 4			/* acch */
+};
+
+#define M32R_SP_REGNUM 15
+
+struct m32r_frame_cache
+{
+  CORE_ADDR base, pc;
+  struct trad_frame_saved_reg *saved_regs;
+};
+
+static struct m32r_frame_cache *
+m32r_linux_sigtramp_frame_cache (struct frame_info *next_frame,
+				 void **this_cache)
+{
+  struct m32r_frame_cache *cache;
+  CORE_ADDR sigcontext_addr, addr;
+  int regnum;
+
+  if ((*this_cache) != NULL)
+    return (*this_cache);
+  cache = FRAME_OBSTACK_ZALLOC (struct m32r_frame_cache);
+  (*this_cache) = cache;
+  cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+
+  cache->base = frame_unwind_register_unsigned (next_frame, M32R_SP_REGNUM);
+  sigcontext_addr = cache->base + 4;
+
+  cache->pc = frame_pc_unwind (next_frame);
+  addr = m32r_linux_sigtramp_start (cache->pc);
+  if (addr == 0)
+    {
+      /* If this is a RT signal trampoline, adjust SIGCONTEXT_ADDR
+         accordingly.  */
+      addr = m32r_linux_rt_sigtramp_start (cache->pc);
+      if (addr)
+	sigcontext_addr += 128;
+      else
+	addr = frame_func_unwind (next_frame);
+    }
+  cache->pc = addr;
+
+  cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+
+  for (regnum = 0; regnum < sizeof (m32r_linux_sc_reg_offset) / 4; regnum++)
+    {
+      if (m32r_linux_sc_reg_offset[regnum] >= 0)
+	cache->saved_regs[regnum].addr =
+	  sigcontext_addr + m32r_linux_sc_reg_offset[regnum];
+    }
+
+  return cache;
+}
+
+static void
+m32r_linux_sigtramp_frame_this_id (struct frame_info *next_frame,
+				   void **this_cache,
+				   struct frame_id *this_id)
+{
+  struct m32r_frame_cache *cache =
+    m32r_linux_sigtramp_frame_cache (next_frame, this_cache);
+
+  (*this_id) = frame_id_build (cache->base, cache->pc);
+}
+
+static void
+m32r_linux_sigtramp_frame_prev_register (struct frame_info *next_frame,
+					 void **this_cache,
+					 int regnum, int *optimizedp,
+					 enum lval_type *lvalp,
+					 CORE_ADDR *addrp,
+					 int *realnump, void *valuep)
+{
+  struct m32r_frame_cache *cache =
+    m32r_linux_sigtramp_frame_cache (next_frame, this_cache);
+
+  trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum,
+				optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind m32r_linux_sigtramp_frame_unwind = {
+  SIGTRAMP_FRAME,
+  m32r_linux_sigtramp_frame_this_id,
+  m32r_linux_sigtramp_frame_prev_register
+};
+
+static const struct frame_unwind *
+m32r_linux_sigtramp_frame_sniffer (struct frame_info *next_frame)
+{
+  CORE_ADDR pc = frame_pc_unwind (next_frame);
+  char *name;
+
+  find_pc_partial_function (pc, &name, NULL, NULL);
+  if (m32r_linux_pc_in_sigtramp (pc, name))
+    return &m32r_linux_sigtramp_frame_unwind;
+
+  return NULL;
+}
+
+static struct link_map_offsets *
+m32r_linux_svr4_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL)
+    {
+      lmp = &lmo;
+
+      /* Everything we need is in the first 8 bytes.  */
+      lmo.r_debug_size = 8;
+      lmo.r_map_offset = 4;
+      lmo.r_map_size = 4;
+
+      /* Everything we need is in the first 20 bytes.  */
+      lmo.link_map_size = 20;
+      lmo.l_addr_offset = 0;
+      lmo.l_addr_size = 4;
+      lmo.l_name_offset = 4;
+      lmo.l_name_size = 4;
+      lmo.l_next_offset = 12;
+      lmo.l_next_size = 4;
+      lmo.l_prev_offset = 16;
+      lmo.l_prev_size = 4;
+    }
+
+  return lmp;
+}
+
+static void
+m32r_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+  frame_unwind_append_sniffer (gdbarch, m32r_linux_sigtramp_frame_sniffer);
+
+  set_solib_svr4_fetch_link_map_offsets
+    (gdbarch, m32r_linux_svr4_fetch_link_map_offsets);
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+extern void _initialize_m32r_linux_tdep (void);
+
+void
+_initialize_m32r_linux_tdep (void)
+{
+  gdbarch_register_osabi (bfd_arch_m32r, 0, GDB_OSABI_LINUX,
+			  m32r_linux_init_abi);
+}
Index: config/m32r/linux.mh
===================================================================
RCS file: config/m32r/linux.mh
diff -N config/m32r/linux.mh
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ config/m32r/linux.mh	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,8 @@
+# Host: M32R based machine running GNU/Linux
+
+NAT_FILE= nm-linux.h
+NATDEPFILES= infptrace.o inftarg.o fork-child.o corelow.o	\
+	m32r-linux-nat.o linux-proc.o gcore.o	\
+	proc-service.o thread-db.o lin-lwp.o linux-nat.o
+
+LOADLIBES= -ldl -rdynamic
Index: config/m32r/linux.mt
===================================================================
RCS file: config/m32r/linux.mt
diff -N config/m32r/linux.mt
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ config/m32r/linux.mt	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,6 @@
+# Target: Renesas M32R running GNU/Linux
+TDEPFILES= m32r-tdep.o m32r-linux-tdep.o remote-m32r-sdi.o glibc-tdep.o solib.o solib-svr4.o solib-legacy.o
+TM_FILE= tm-linux.h
+
+SIM_OBS = remote-sim.o
+SIM = ../sim/m32r/libsim.a
Index: config/m32r/m32r.mh
===================================================================
RCS file: config/m32r/m32r.mh
diff -N config/m32r/m32r.mh
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ config/m32r/m32r.mh	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,8 @@
+# Host: M32R running GNU/Linux
+
+NAT_FILE= nm-linux.h
+NATDEPFILES= infptrace.o inftarg.o fork-child.o corelow.o \
+	core-regset.o linux-proc.o gcore.o \
+	proc-service.o thread-db.o lin-lwp.o
+
+LOADLIBES = -ldl -rdynamic
Index: config/m32r/nm-linux.h
===================================================================
RCS file: config/m32r/nm-linux.h
diff -N config/m32r/nm-linux.h
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ config/m32r/nm-linux.h	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,29 @@
+/* Definitions to make GDB run on an M32R based machine under GNU/Linux.
+   Copyright 2004 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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef NM_M32R_LINUX_H
+#define NM_M32R_LINUX_H
+
+#include "config/nm-linux.h"
+
+/* Override copies of {fetch,store}_inferior_registers in infptrace.c.  */
+#define FETCH_INFERIOR_REGISTERS
+
+#endif /* NM_M32R_LINUX_H */
Index: config/m32r/tm-linux.h
===================================================================
RCS file: config/m32r/tm-linux.h
diff -N config/m32r/tm-linux.h
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ config/m32r/tm-linux.h	20 Aug 2004 05:54:29 -0000
@@ -0,0 +1,29 @@
+/* Target-specific definitions for GNU/Linux running on a Renesas
+   M32R. 
+
+   Copyright 2004 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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef TM_LINUX_H
+#define TM_LINUX_H
+
+/* Pull in GNU/Linux generic defs.  */
+#include "config/tm-linux.h"
+
+#endif /* #ifndef TM_LINUX_H */