/* Low level Alpha interface, for GDB when running native.
   Copyright (C) 1993-2013 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 "gdb_string.h"
#include "inferior.h"
#include "gdbcore.h"
#include "target.h"
#include "procfs.h"
#include "regcache.h"

#include "alpha-tdep.h"

#include <sys/ptrace.h>
#include <alpha/coreregs.h>
#include <sys/user.h>


/* Extract the register values out of the core file and store
   them into REGCACHE.

   CORE_REG_SECT points to the register values themselves, read into memory.
   CORE_REG_SIZE is the size of that area.
   WHICH says which set of registers we are handling (0 = int, 2 = float
   on machines where they are discontiguous).
   REG_ADDR is the offset from u.u_ar0 to the register values relative to
   core_reg_sect.  This is used with old-fashioned core files to
   locate the registers in a large upage-plus-stack ".reg" section.
   Original upage address X is at location core_reg_sect+x+reg_addr.  */

static void
fetch_osf_core_registers (struct regcache *regcache,
			  char *core_reg_sect, unsigned core_reg_size,
			  int which, CORE_ADDR reg_addr)
{
  struct gdbarch *gdbarch = get_regcache_arch (regcache);
  int regno;
  int addr;
  int bad_reg = -1;

  /* Table to map a gdb regnum to an index in the core register
     section.  The floating point register values are garbage in
     OSF/1.2 core files.  OSF5 uses different names for the register
     enum list, need to handle two cases.  The actual values are the
     same.  */
  static int const core_reg_mapping[ALPHA_NUM_REGS] =
  {
#ifdef NCF_REGS
#define EFL NCF_REGS
    CF_V0, CF_T0, CF_T1, CF_T2, CF_T3, CF_T4, CF_T5, CF_T6,
    CF_T7, CF_S0, CF_S1, CF_S2, CF_S3, CF_S4, CF_S5, CF_S6,
    CF_A0, CF_A1, CF_A2, CF_A3, CF_A4, CF_A5, CF_T8, CF_T9,
    CF_T10, CF_T11, CF_RA, CF_T12, CF_AT, CF_GP, CF_SP, -1,
    EFL + 0, EFL + 1, EFL + 2, EFL + 3,
    EFL + 4, EFL + 5, EFL + 6, EFL + 7,
    EFL + 8, EFL + 9, EFL + 10, EFL + 11,
    EFL + 12, EFL + 13, EFL + 14, EFL + 15,
    EFL + 16, EFL + 17, EFL + 18, EFL + 19,
    EFL + 20, EFL + 21, EFL + 22, EFL + 23,
    EFL + 24, EFL + 25, EFL + 26, EFL + 27,
    EFL + 28, EFL + 29, EFL + 30, EFL + 31,
    CF_PC, -1, -1
#else
#define EFL (EF_SIZE / 8)
    EF_V0, EF_T0, EF_T1, EF_T2, EF_T3, EF_T4, EF_T5, EF_T6,
    EF_T7, EF_S0, EF_S1, EF_S2, EF_S3, EF_S4, EF_S5, EF_S6,
    EF_A0, EF_A1, EF_A2, EF_A3, EF_A4, EF_A5, EF_T8, EF_T9,
    EF_T10, EF_T11, EF_RA, EF_T12, EF_AT, EF_GP, EF_SP, -1,
    EFL + 0, EFL + 1, EFL + 2, EFL + 3,
    EFL + 4, EFL + 5, EFL + 6, EFL + 7,
    EFL + 8, EFL + 9, EFL + 10, EFL + 11,
    EFL + 12, EFL + 13, EFL + 14, EFL + 15,
    EFL + 16, EFL + 17, EFL + 18, EFL + 19,
    EFL + 20, EFL + 21, EFL + 22, EFL + 23,
    EFL + 24, EFL + 25, EFL + 26, EFL + 27,
    EFL + 28, EFL + 29, EFL + 30, EFL + 31,
    EF_PC, -1, -1
#endif
  };

  for (regno = 0; regno < ALPHA_NUM_REGS; regno++)
    {
      if (gdbarch_cannot_fetch_register (gdbarch, regno))
	{
	  regcache_raw_supply (regcache, regno, NULL);
	  continue;
	}

      if (regno == ALPHA_ZERO_REGNUM)
	{
	  const gdb_byte zero[8] = { 0 };

	  regcache_raw_supply (regcache, regno, zero);
	  continue;
	}

      addr = 8 * core_reg_mapping[regno];
      if (addr < 0 || addr >= core_reg_size)
	{
	  /* ??? UNIQUE is a new addition.  Don't generate an error.  */
	  if (regno == ALPHA_UNIQUE_REGNUM)
	    {
	      regcache_raw_supply (regcache, regno, NULL);
	      continue;
	    }
	  if (bad_reg < 0)
	    bad_reg = regno;
	}
      else
	{
	  regcache_raw_supply (regcache, regno, core_reg_sect + addr);
	}
    }
  if (bad_reg >= 0)
    {
      error (_("Register %s not found in core file."),
	     gdbarch_register_name (gdbarch, bad_reg));
    }
}


#include <sys/procfs.h>
/* Prototypes for supply_gregset etc.  */
#include "gregset.h"

/* See the comment in m68k-tdep.c regarding the utility of these
   functions.  */

void
supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
{
  const long *regp = gregsetp->regs;

  /* PC is in slot 32.  */
  alpha_supply_int_regs (regcache, -1, regp, regp + 31, NULL);
}

void
fill_gregset (const struct regcache *regcache,
	      gdb_gregset_t *gregsetp, int regno)
{
  long *regp = gregsetp->regs;

  /* PC is in slot 32.  */
  alpha_fill_int_regs (regcache, regno, regp, regp + 31, NULL);
}

/* Now we do the same thing for floating-point registers.
   Again, see the comments in m68k-tdep.c.  */

void
supply_fpregset (struct regcache *regcache, const gdb_fpregset_t *fpregsetp)
{
  const long *regp = fpregsetp->regs;

  /* FPCR is in slot 32.  */
  alpha_supply_fp_regs (regcache, -1, regp, regp + 31);
}

void
fill_fpregset (const struct regcache *regcache,
	       gdb_fpregset_t *fpregsetp, int regno)
{
  long *regp = fpregsetp->regs;

  /* FPCR is in slot 32.  */
  alpha_fill_fp_regs (regcache, regno, regp, regp + 31);
}


/* Register that we are able to handle alpha core file formats.  */

static struct core_fns alpha_osf_core_fns =
{
  /* This really is bfd_target_unknown_flavour.  */

  bfd_target_unknown_flavour,		/* core_flavour */
  default_check_format,			/* check_format */
  default_core_sniffer,			/* core_sniffer */
  fetch_osf_core_registers,		/* core_read_registers */
  NULL					/* next */
};

/* Provide a prototype to silence -Wmissing-prototypes.  */
extern initialize_file_ftype _initialize_alpha_nat;

void
_initialize_alpha_nat (void)
{
  struct target_ops *t;

  t = procfs_target ();
  add_target (t);

  deprecated_add_core_fns (&alpha_osf_core_fns);
}