/* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger.

   Copyright (C) 2003-2022 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 "gdbcore.h"
#include "regcache.h"
#include "mn10300-tdep.h"
#include "bfd.h"
#include "elf-bfd.h"
#include "osabi.h"
#include "regset.h"
#include "solib-svr4.h"
#include "frame.h"
#include "trad-frame.h"
#include "tramp-frame.h"
#include "linux-tdep.h"
#include "gdbarch.h"

/* Transliterated from <asm-mn10300/elf.h>...  */
#define MN10300_ELF_NGREG 28
#define MN10300_ELF_NFPREG 32

typedef gdb_byte   mn10300_elf_greg_t[4];
typedef mn10300_elf_greg_t mn10300_elf_gregset_t[MN10300_ELF_NGREG];

typedef gdb_byte   mn10300_elf_fpreg_t[4];
typedef struct
{
  mn10300_elf_fpreg_t fpregs[MN10300_ELF_NFPREG];
  gdb_byte    fpcr[4];
} mn10300_elf_fpregset_t;

/* elf_gregset_t register indices stolen from include/asm-mn10300/ptrace.h.  */
#define MN10300_ELF_GREGSET_T_REG_INDEX_A3	0
#define MN10300_ELF_GREGSET_T_REG_INDEX_A2	1
#define MN10300_ELF_GREGSET_T_REG_INDEX_D3	2
#define	MN10300_ELF_GREGSET_T_REG_INDEX_D2	3
#define MN10300_ELF_GREGSET_T_REG_INDEX_MCVF	4
#define	MN10300_ELF_GREGSET_T_REG_INDEX_MCRL	5
#define MN10300_ELF_GREGSET_T_REG_INDEX_MCRH	6
#define	MN10300_ELF_GREGSET_T_REG_INDEX_MDRQ	7
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E1	8
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E0	9
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E7	10
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E6	11
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E5	12
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E4	13
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E3	14
#define	MN10300_ELF_GREGSET_T_REG_INDEX_E2	15
#define	MN10300_ELF_GREGSET_T_REG_INDEX_SP	16
#define	MN10300_ELF_GREGSET_T_REG_INDEX_LAR	17
#define	MN10300_ELF_GREGSET_T_REG_INDEX_LIR	18
#define	MN10300_ELF_GREGSET_T_REG_INDEX_MDR	19
#define	MN10300_ELF_GREGSET_T_REG_INDEX_A1	20
#define	MN10300_ELF_GREGSET_T_REG_INDEX_A0	21
#define	MN10300_ELF_GREGSET_T_REG_INDEX_D1	22
#define	MN10300_ELF_GREGSET_T_REG_INDEX_D0	23
#define MN10300_ELF_GREGSET_T_REG_INDEX_ORIG_D0	24
#define	MN10300_ELF_GREGSET_T_REG_INDEX_EPSW	25
#define	MN10300_ELF_GREGSET_T_REG_INDEX_PC	26

/* New gdbarch API for corefile registers.
   Given a section name and size, create a struct reg object
   with a supply_register and a collect_register method.  */

/* Copy register value of REGNUM from regset to regcache.
   If REGNUM is -1, do this for all gp registers in regset.  */

static void
am33_supply_gregset_method (const struct regset *regset, 
			    struct regcache *regcache, 
			    int regnum, const void *gregs, size_t len)
{
  const mn10300_elf_greg_t *regp = (const mn10300_elf_greg_t *) gregs;
  int i;

  gdb_assert (len >= sizeof (mn10300_elf_gregset_t));

  switch (regnum) {
  case E_D0_REGNUM:
    regcache->raw_supply (E_D0_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D0));
    break;
  case E_D1_REGNUM:
    regcache->raw_supply (E_D1_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D1));
    break;
  case E_D2_REGNUM:
    regcache->raw_supply (E_D2_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D2));
    break;
  case E_D3_REGNUM:
    regcache->raw_supply (E_D3_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D3));
    break;
  case E_A0_REGNUM:
    regcache->raw_supply (E_A0_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A0));
    break;
  case E_A1_REGNUM:
    regcache->raw_supply (E_A1_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A1));
    break;
  case E_A2_REGNUM:
    regcache->raw_supply (E_A2_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A2));
    break;
  case E_A3_REGNUM:
    regcache->raw_supply (E_A3_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A3));
    break;
  case E_SP_REGNUM:
    regcache->raw_supply (E_SP_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_SP));
    break;
  case E_PC_REGNUM:
    regcache->raw_supply (E_PC_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_PC));
    break;
  case E_MDR_REGNUM:
    regcache->raw_supply (E_MDR_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MDR));
    break;
  case E_PSW_REGNUM:
    regcache->raw_supply (E_PSW_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_EPSW));
    break;
  case E_LIR_REGNUM:
    regcache->raw_supply (E_LIR_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_LIR));
    break;
  case E_LAR_REGNUM:
    regcache->raw_supply (E_LAR_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_LAR));
    break;
  case E_MDRQ_REGNUM:
    regcache->raw_supply (E_MDRQ_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MDRQ));
    break;
  case E_E0_REGNUM:
    regcache->raw_supply (E_E0_REGNUM,   
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E0));
    break;
  case E_E1_REGNUM:
    regcache->raw_supply (E_E1_REGNUM,
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E1));
    break;
  case E_E2_REGNUM:
    regcache->raw_supply (E_E2_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E2));
    break;
  case E_E3_REGNUM:
    regcache->raw_supply (E_E3_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E3));
    break;
  case E_E4_REGNUM:
    regcache->raw_supply (E_E4_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E4));
    break;
  case E_E5_REGNUM:
    regcache->raw_supply (E_E5_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E5));
    break;
  case E_E6_REGNUM:
    regcache->raw_supply (E_E6_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E6));
    break;
  case E_E7_REGNUM:
    regcache->raw_supply (E_E7_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E7));
    break;

    /* ssp, msp, and usp are inaccessible.  */
  case E_E8_REGNUM:
    regcache->raw_supply_zeroed (E_E8_REGNUM);
    break;
  case E_E9_REGNUM:
    regcache->raw_supply_zeroed (E_E9_REGNUM);
    break;
  case E_E10_REGNUM:
    regcache->raw_supply_zeroed (E_E10_REGNUM);
    break;
  case E_MCRH_REGNUM:
    regcache->raw_supply (E_MCRH_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCRH));
    break;
  case E_MCRL_REGNUM:
    regcache->raw_supply (E_MCRL_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCRL));
    break;
  case E_MCVF_REGNUM:
    regcache->raw_supply (E_MCVF_REGNUM, 
			  (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCVF));
    break;
  case E_FPCR_REGNUM:
    /* FPCR is numbered among the GP regs, but handled as an FP reg.
       Do nothing.  */
    break;
  case E_FPCR_REGNUM + 1:
    /* The two unused registers beyond fpcr are inaccessible.  */
    regcache->raw_supply_zeroed (E_FPCR_REGNUM + 1);
    break;
  case E_FPCR_REGNUM + 2:
    regcache->raw_supply_zeroed (E_FPCR_REGNUM + 2);
    break;
  default:	/* An error, obviously, but should we error out?  */
    break;
  case -1:
    for (i = 0; i < MN10300_ELF_NGREG; i++)
      am33_supply_gregset_method (regset, regcache, i, gregs, len);
    break;
  }
  return;
}

/* Copy fp register value of REGNUM from regset to regcache.
   If REGNUM is -1, do this for all fp registers in regset.  */

static void
am33_supply_fpregset_method (const struct regset *regset, 
			     struct regcache *regcache, 
			     int regnum, const void *fpregs, size_t len)
{
  const mn10300_elf_fpregset_t *fpregset
    = (const mn10300_elf_fpregset_t *) fpregs;

  gdb_assert (len >= sizeof (mn10300_elf_fpregset_t));

  if (regnum == -1)
    {
      int i;

      for (i = 0; i < MN10300_ELF_NFPREG; i++)
	am33_supply_fpregset_method (regset, regcache,
				     E_FS0_REGNUM + i, fpregs, len);
      am33_supply_fpregset_method (regset, regcache, 
				   E_FPCR_REGNUM, fpregs, len);
    }
  else if (regnum == E_FPCR_REGNUM)
    regcache->raw_supply (E_FPCR_REGNUM, &fpregset->fpcr);
  else if (E_FS0_REGNUM <= regnum
	   && regnum < E_FS0_REGNUM + MN10300_ELF_NFPREG)
    regcache->raw_supply (regnum, &fpregset->fpregs[regnum - E_FS0_REGNUM]);

  return;
}

/* Copy register values from regcache to regset.  */

static void
am33_collect_gregset_method (const struct regset *regset, 
			     const struct regcache *regcache, 
			     int regnum, void *gregs, size_t len)
{
  mn10300_elf_gregset_t *regp = (gdb_byte (*)[28][4]) gregs;
  int i;

  gdb_assert (len >= sizeof (mn10300_elf_gregset_t));

  switch (regnum) {
  case E_D0_REGNUM:
    regcache->raw_collect (E_D0_REGNUM,
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D0));
    break;
  case E_D1_REGNUM:
    regcache->raw_collect (E_D1_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D1));
    break;
  case E_D2_REGNUM:
    regcache->raw_collect (E_D2_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D2));
    break;
  case E_D3_REGNUM:
    regcache->raw_collect (E_D3_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_D3));
    break;
  case E_A0_REGNUM:
    regcache->raw_collect (E_A0_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A0));
    break;
  case E_A1_REGNUM:
    regcache->raw_collect (E_A1_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A1));
    break;
  case E_A2_REGNUM:
    regcache->raw_collect (E_A2_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A2));
    break;
  case E_A3_REGNUM:
    regcache->raw_collect (E_A3_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_A3));
    break;
  case E_SP_REGNUM:
    regcache->raw_collect (E_SP_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_SP));
    break;
  case E_PC_REGNUM:
    regcache->raw_collect (E_PC_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_PC));
    break;
  case E_MDR_REGNUM:
    regcache->raw_collect (E_MDR_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MDR));
    break;
  case E_PSW_REGNUM:
    regcache->raw_collect (E_PSW_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_EPSW));
    break;
  case E_LIR_REGNUM:
    regcache->raw_collect (E_LIR_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_LIR));
    break;
  case E_LAR_REGNUM:
    regcache->raw_collect (E_LAR_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_LAR));
    break;
  case E_MDRQ_REGNUM:
    regcache->raw_collect (E_MDRQ_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MDRQ));
    break;
  case E_E0_REGNUM:
    regcache->raw_collect (E_E0_REGNUM,   
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E0));
    break;
  case E_E1_REGNUM:
    regcache->raw_collect (E_E1_REGNUM,
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E1));
    break;
  case E_E2_REGNUM:
    regcache->raw_collect (E_E2_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E2));
    break;
  case E_E3_REGNUM:
    regcache->raw_collect (E_E3_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E3));
    break;
  case E_E4_REGNUM:
    regcache->raw_collect (E_E4_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E4));
    break;
  case E_E5_REGNUM:
    regcache->raw_collect (E_E5_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E5));
    break;
  case E_E6_REGNUM:
    regcache->raw_collect (E_E6_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E6));
    break;
  case E_E7_REGNUM:
    regcache->raw_collect (E_E7_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_E7));
    break;

    /* ssp, msp, and usp are inaccessible.  */
  case E_E8_REGNUM:
    /* The gregset struct has noplace to put this: do nothing.  */
    break;
  case E_E9_REGNUM:
    /* The gregset struct has noplace to put this: do nothing.  */
    break;
  case E_E10_REGNUM:
    /* The gregset struct has noplace to put this: do nothing.  */
    break;
  case E_MCRH_REGNUM:
    regcache->raw_collect (E_MCRH_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCRH));
    break;
  case E_MCRL_REGNUM:
    regcache->raw_collect (E_MCRL_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCRL));
    break;
  case E_MCVF_REGNUM:
    regcache->raw_collect (E_MCVF_REGNUM, 
			   (regp + MN10300_ELF_GREGSET_T_REG_INDEX_MCVF));
    break;
  case E_FPCR_REGNUM:
    /* FPCR is numbered among the GP regs, but handled as an FP reg.
       Do nothing.  */
    break;
  case E_FPCR_REGNUM + 1:
    /* The gregset struct has noplace to put this: do nothing.  */
    break;
  case E_FPCR_REGNUM + 2:
    /* The gregset struct has noplace to put this: do nothing.  */
    break;
  default:	/* An error, obviously, but should we error out?  */
    break;
  case -1:
    for (i = 0; i < MN10300_ELF_NGREG; i++)
      am33_collect_gregset_method (regset, regcache, i, gregs, len);
    break;
  }
  return;
}

/* Copy fp register values from regcache to regset.  */

static void
am33_collect_fpregset_method (const struct regset *regset, 
			      const struct regcache *regcache, 
			      int regnum, void *fpregs, size_t len)
{
  mn10300_elf_fpregset_t *fpregset = (mn10300_elf_fpregset_t *) fpregs;

  gdb_assert (len >= sizeof (mn10300_elf_fpregset_t));

  if (regnum == -1)
    {
      int i;
      for (i = 0; i < MN10300_ELF_NFPREG; i++)
	am33_collect_fpregset_method (regset, regcache, E_FS0_REGNUM + i,
				      fpregs, len);
      am33_collect_fpregset_method (regset, regcache, 
				    E_FPCR_REGNUM, fpregs, len);
    }
  else if (regnum == E_FPCR_REGNUM)
    regcache->raw_collect (E_FPCR_REGNUM, &fpregset->fpcr);
  else if (E_FS0_REGNUM <= regnum
	   && regnum < E_FS0_REGNUM + MN10300_ELF_NFPREG)
    regcache->raw_collect (regnum, &fpregset->fpregs[regnum - E_FS0_REGNUM]);

  return;
}

static const struct regset am33_gregset =
  {
    NULL, am33_supply_gregset_method, am33_collect_gregset_method
  };

static const struct regset am33_fpregset =
  {
    NULL, am33_supply_fpregset_method, am33_collect_fpregset_method
  };

/* Iterate over core file register note sections.  */

static void
am33_iterate_over_regset_sections (struct gdbarch *gdbarch,
				   iterate_over_regset_sections_cb *cb,
				   void *cb_data,
				   const struct regcache *regcache)
{
  cb (".reg", sizeof (mn10300_elf_gregset_t), sizeof (mn10300_elf_gregset_t),
      &am33_gregset, NULL, cb_data);
  cb (".reg2", sizeof (mn10300_elf_fpregset_t), sizeof (mn10300_elf_fpregset_t),
      &am33_fpregset, NULL, cb_data);
}

static void
am33_linux_sigframe_cache_init (const struct tramp_frame *self,
				frame_info_ptr this_frame,
				struct trad_frame_cache *this_cache,
				CORE_ADDR func);

static const struct tramp_frame am33_linux_sigframe = {
  SIGTRAMP_FRAME,
  1,
  {
    /* mov     119,d0 */
    { 0x2c, ULONGEST_MAX },
    { 0x77, ULONGEST_MAX },
    { 0x00, ULONGEST_MAX },
    /* syscall 0 */
    { 0xf0, ULONGEST_MAX },
    { 0xe0, ULONGEST_MAX },
    { TRAMP_SENTINEL_INSN, ULONGEST_MAX }
  },
  am33_linux_sigframe_cache_init
};

static const struct tramp_frame am33_linux_rt_sigframe = {
  SIGTRAMP_FRAME,
  1,
  {
    /* mov     173,d0 */
    { 0x2c, ULONGEST_MAX },
    { 0xad, ULONGEST_MAX },
    { 0x00, ULONGEST_MAX },
    /* syscall 0 */
    { 0xf0, ULONGEST_MAX },
    { 0xe0, ULONGEST_MAX },
    { TRAMP_SENTINEL_INSN, ULONGEST_MAX }
  },
  am33_linux_sigframe_cache_init
};

/* Relevant struct definitions for signal handling...

From arch/mn10300/kernel/sigframe.h:

struct sigframe
{
	void (*pretcode)(void);
	int sig;
	struct sigcontext *psc;
	struct sigcontext sc;
	struct fpucontext fpuctx;
	unsigned long extramask[_NSIG_WORDS-1];
	char retcode[8];
};

struct rt_sigframe
{
	void (*pretcode)(void);
	int sig;
	struct siginfo *pinfo;
	void *puc;
	struct siginfo info;
	struct ucontext uc;
	struct fpucontext fpuctx;
	char retcode[8];
};

From include/asm-mn10300/ucontext.h:

struct ucontext {
	unsigned long	  uc_flags;
	struct ucontext  *uc_link;
	stack_t		  uc_stack;
	struct sigcontext uc_mcontext;
	sigset_t	  uc_sigmask;
};

From include/asm-mn10300/sigcontext.h:

struct fpucontext {
	unsigned long	fs[32];
	unsigned long	fpcr;
};

struct sigcontext {
	unsigned long	d0;
	unsigned long	d1;
	unsigned long	d2;
	unsigned long	d3;
	unsigned long	a0;
	unsigned long	a1;
	unsigned long	a2;
	unsigned long	a3;
	unsigned long	e0;
	unsigned long	e1;
	unsigned long	e2;
	unsigned long	e3;
	unsigned long	e4;
	unsigned long	e5;
	unsigned long	e6;
	unsigned long	e7;
	unsigned long	lar;
	unsigned long	lir;
	unsigned long	mdr;
	unsigned long	mcvf;
	unsigned long	mcrl;
	unsigned long	mcrh;
	unsigned long	mdrq;
	unsigned long	sp;
	unsigned long	epsw;
	unsigned long	pc;
	struct fpucontext *fpucontext;
	unsigned long	oldmask;
}; */


#define AM33_SIGCONTEXT_D0 0
#define AM33_SIGCONTEXT_D1 4
#define AM33_SIGCONTEXT_D2 8
#define AM33_SIGCONTEXT_D3 12
#define AM33_SIGCONTEXT_A0 16
#define AM33_SIGCONTEXT_A1 20
#define AM33_SIGCONTEXT_A2 24
#define AM33_SIGCONTEXT_A3 28
#define AM33_SIGCONTEXT_E0 32
#define AM33_SIGCONTEXT_E1 36
#define AM33_SIGCONTEXT_E2 40
#define AM33_SIGCONTEXT_E3 44
#define AM33_SIGCONTEXT_E4 48
#define AM33_SIGCONTEXT_E5 52
#define AM33_SIGCONTEXT_E6 56
#define AM33_SIGCONTEXT_E7 60
#define AM33_SIGCONTEXT_LAR 64
#define AM33_SIGCONTEXT_LIR 68
#define AM33_SIGCONTEXT_MDR 72
#define AM33_SIGCONTEXT_MCVF 76
#define AM33_SIGCONTEXT_MCRL 80
#define AM33_SIGCONTEXT_MCRH 84
#define AM33_SIGCONTEXT_MDRQ 88
#define AM33_SIGCONTEXT_SP 92
#define AM33_SIGCONTEXT_EPSW 96
#define AM33_SIGCONTEXT_PC 100
#define AM33_SIGCONTEXT_FPUCONTEXT 104


static void
am33_linux_sigframe_cache_init (const struct tramp_frame *self,
				frame_info_ptr this_frame,
				struct trad_frame_cache *this_cache,
				CORE_ADDR func)
{
  CORE_ADDR sc_base, fpubase;
  int i;

  sc_base = get_frame_register_unsigned (this_frame, E_SP_REGNUM);
  if (self == &am33_linux_sigframe)
    {
      sc_base += 8;
      sc_base = get_frame_memory_unsigned (this_frame, sc_base, 4);
    }
  else
    {
      sc_base += 12;
      sc_base = get_frame_memory_unsigned (this_frame, sc_base, 4);
      sc_base += 20;
    }

  trad_frame_set_reg_addr (this_cache, E_D0_REGNUM,
			   sc_base + AM33_SIGCONTEXT_D0);
  trad_frame_set_reg_addr (this_cache, E_D1_REGNUM,
			   sc_base + AM33_SIGCONTEXT_D1);
  trad_frame_set_reg_addr (this_cache, E_D2_REGNUM,
			   sc_base + AM33_SIGCONTEXT_D2);
  trad_frame_set_reg_addr (this_cache, E_D3_REGNUM,
			   sc_base + AM33_SIGCONTEXT_D3);

  trad_frame_set_reg_addr (this_cache, E_A0_REGNUM,
			   sc_base + AM33_SIGCONTEXT_A0);
  trad_frame_set_reg_addr (this_cache, E_A1_REGNUM,
			   sc_base + AM33_SIGCONTEXT_A1);
  trad_frame_set_reg_addr (this_cache, E_A2_REGNUM,
			   sc_base + AM33_SIGCONTEXT_A2);
  trad_frame_set_reg_addr (this_cache, E_A3_REGNUM,
			   sc_base + AM33_SIGCONTEXT_A3);

  trad_frame_set_reg_addr (this_cache, E_E0_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E0);
  trad_frame_set_reg_addr (this_cache, E_E1_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E1);
  trad_frame_set_reg_addr (this_cache, E_E2_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E2);
  trad_frame_set_reg_addr (this_cache, E_E3_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E3);
  trad_frame_set_reg_addr (this_cache, E_E4_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E4);
  trad_frame_set_reg_addr (this_cache, E_E5_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E5);
  trad_frame_set_reg_addr (this_cache, E_E6_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E6);
  trad_frame_set_reg_addr (this_cache, E_E7_REGNUM,
			   sc_base + AM33_SIGCONTEXT_E7);

  trad_frame_set_reg_addr (this_cache, E_LAR_REGNUM,
			   sc_base + AM33_SIGCONTEXT_LAR);
  trad_frame_set_reg_addr (this_cache, E_LIR_REGNUM,
			   sc_base + AM33_SIGCONTEXT_LIR);
  trad_frame_set_reg_addr (this_cache, E_MDR_REGNUM,
			   sc_base + AM33_SIGCONTEXT_MDR);
  trad_frame_set_reg_addr (this_cache, E_MCVF_REGNUM,
			   sc_base + AM33_SIGCONTEXT_MCVF);
  trad_frame_set_reg_addr (this_cache, E_MCRL_REGNUM,
			   sc_base + AM33_SIGCONTEXT_MCRL);
  trad_frame_set_reg_addr (this_cache, E_MDRQ_REGNUM,
			   sc_base + AM33_SIGCONTEXT_MDRQ);

  trad_frame_set_reg_addr (this_cache, E_SP_REGNUM,
			   sc_base + AM33_SIGCONTEXT_SP);
  trad_frame_set_reg_addr (this_cache, E_PSW_REGNUM,
			   sc_base + AM33_SIGCONTEXT_EPSW);
  trad_frame_set_reg_addr (this_cache, E_PC_REGNUM,
			   sc_base + AM33_SIGCONTEXT_PC);

  fpubase = get_frame_memory_unsigned (this_frame,
				       sc_base + AM33_SIGCONTEXT_FPUCONTEXT,
				       4);
  if (fpubase)
    {
      for (i = 0; i < 32; i++)
	{
	  trad_frame_set_reg_addr (this_cache, E_FS0_REGNUM + i,
				   fpubase + 4 * i);
	}
      trad_frame_set_reg_addr (this_cache, E_FPCR_REGNUM, fpubase + 4 * 32);
    }

  trad_frame_set_id (this_cache, frame_id_build (sc_base, func));
}

/* AM33 GNU/Linux osabi has been recognized.
   Now's our chance to register our corefile handling.  */

static void
am33_linux_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  linux_init_abi (info, gdbarch, 0);

  set_gdbarch_iterate_over_regset_sections
    (gdbarch, am33_iterate_over_regset_sections);
  set_solib_svr4_fetch_link_map_offsets
    (gdbarch, linux_ilp32_fetch_link_map_offsets);

  tramp_frame_prepend_unwinder (gdbarch, &am33_linux_sigframe);
  tramp_frame_prepend_unwinder (gdbarch, &am33_linux_rt_sigframe);
}

void _initialize_mn10300_linux_tdep ();
void
_initialize_mn10300_linux_tdep ()
{
  gdbarch_register_osabi (bfd_arch_mn10300, 0,
			  GDB_OSABI_LINUX, am33_linux_init_osabi);
}