* coffgen.c (coff_bfd_make_debug_symbol): Improve comment.

[deliverable/binutils-gdb.git] / bfd / coff-h8300.c

/* BFD back-end for Hitachi H8/300 COFF binaries.
   Copyright 1990, 91, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
   Written by Steve Chamberlain, <sac@cygnus.com>.

This file is part of BFD, the Binary File Descriptor library.

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 "bfd.h"
#include "sysdep.h"
#include "obstack.h"
#include "libbfd.h"
#include "bfdlink.h"
#include "genlink.h"
#include "coff/h8300.h"
#include "coff/internal.h"
#include "libcoff.h"

#define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (1)


/* special handling for H8/300 relocs.
   We only come here for pcrel stuff and return normally if not an -r link.
   When doing -r, we can't do any arithmetic for the pcrel stuff, because
   the code in reloc.c assumes that we can manipulate the targets of
   the pcrel branches.  This isn't so, since the H8/300 can do relaxing, 
   which means that the gap after the instruction may not be enough to
   contain the offset required for the branch, so we have to use the only
   the addend until the final link */

static bfd_reloc_status_type
special (abfd, reloc_entry, symbol, data, input_section, output_bfd,
		 error_message)
     bfd *abfd;
     arelent *reloc_entry;
     asymbol *symbol;
     PTR data;
     asection *input_section;
     bfd *output_bfd;
     char **error_message;
{
  if (output_bfd == (bfd *) NULL)
    return bfd_reloc_continue;

  return bfd_reloc_ok;
}

static reloc_howto_type howto_table[] =
{
  HOWTO (R_RELBYTE, 0, 0, 8, false, 0, complain_overflow_bitfield, special, "8", false, 0x000000ff, 0x000000ff, false),
  HOWTO (R_RELWORD, 0, 1, 16, false, 0, complain_overflow_bitfield, special, "16", false, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_RELLONG, 0, 2, 32, false, 0, complain_overflow_bitfield, special, "32", false, 0xffffffff, 0xffffffff, false),
  HOWTO (R_PCRBYTE, 0, 0, 8, true, 0, complain_overflow_signed, special, "DISP8", false, 0x000000ff, 0x000000ff, true),
  HOWTO (R_PCRWORD, 0, 1, 16, true, 0, complain_overflow_signed, special, "DISP16", false, 0x0000ffff, 0x0000ffff, true),
  HOWTO (R_PCRLONG, 0, 2, 32, true, 0, complain_overflow_signed, special, "DISP32", false, 0xffffffff, 0xffffffff, true),
  HOWTO (R_MOVB1, 0, 1, 16, false, 0, complain_overflow_bitfield, special, "16/8", false, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_MOVB2, 0, 1, 16, false, 0, complain_overflow_bitfield, special, "8/16", false, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_JMP1, 0, 1, 16, false, 0, complain_overflow_bitfield, special, "16/pcrel", false, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_JMP2, 0, 0, 8, false, 0, complain_overflow_bitfield, special, "pcrecl/16", false, 0x000000ff, 0x000000ff, false),


  HOWTO (R_JMPL1, 0, 2, 32, false, 0, complain_overflow_bitfield, special, "24/pcrell", false, 0x00ffffff, 0x00ffffff, false),
  HOWTO (R_JMPL_B8, 0, 0, 8, false, 0, complain_overflow_bitfield, special, "pc8/24", false, 0x000000ff, 0x000000ff, false),

  HOWTO (R_MOVLB1, 0, 1, 16, false, 0, complain_overflow_bitfield,special, "24/8", false, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_MOVLB2, 0, 1, 16, false, 0, complain_overflow_bitfield, special, "8/24", false, 0x0000ffff, 0x0000ffff, false),

  /* An indirect reference to a function.  This causes the function's address
     to be added to the function vector in lo-mem and puts the address of
     the function vector's entry in the jsr instruction.  */
  HOWTO (R_MEM_INDIRECT, 0, 0, 8, false, 0, complain_overflow_bitfield, special, "8/indirect", false, 0x000000ff, 0x000000ff, false),

};


/* Turn a howto into a reloc number */

#define SELECT_RELOC(x,howto) \
  { x.r_type = select_reloc(howto); }

#define BADMAG(x) (H8300BADMAG(x)&& H8300HBADMAG(x))
#define H8300 1			/* Customize coffcode.h */
#define __A_MAGIC_SET__



/* Code to swap in the reloc */
#define SWAP_IN_RELOC_OFFSET   bfd_h_get_32
#define SWAP_OUT_RELOC_OFFSET bfd_h_put_32
#define SWAP_OUT_RELOC_EXTRA(abfd, src, dst) \
  dst->r_stuff[0] = 'S'; \
  dst->r_stuff[1] = 'C';


static int
select_reloc (howto)
     reloc_howto_type *howto;
{
  return howto->type;
}

/* Code to turn a r_type into a howto ptr, uses the above howto table
   */

static void
rtype2howto (internal, dst)
     arelent *internal;
     struct internal_reloc *dst;
{
  switch (dst->r_type)
    {
    case R_RELBYTE:
      internal->howto = howto_table + 0;
      break;
    case R_RELWORD:
      internal->howto = howto_table + 1;
      break;
    case R_RELLONG:
      internal->howto = howto_table + 2;
      break;
    case R_PCRBYTE:
      internal->howto = howto_table + 3;
      break;
    case R_PCRWORD:
      internal->howto = howto_table + 4;
      break;
    case R_PCRLONG:
      internal->howto = howto_table + 5;
      break;
    case R_MOVB1:
      internal->howto = howto_table + 6;
      break;
    case R_MOVB2:
      internal->howto = howto_table + 7;
      break;
    case R_JMP1:
      internal->howto = howto_table + 8;
      break;
    case R_JMP2:
      internal->howto = howto_table + 9;
      break;
    case R_JMPL1:
      internal->howto = howto_table + 10;
      break;
    case R_JMPL_B8:
      internal->howto = howto_table + 11;
      break;
    case R_MOVLB1:
      internal->howto = howto_table + 12;
      break;
    case R_MOVLB2:
      internal->howto = howto_table + 13;
      break;
    case R_MEM_INDIRECT:
      internal->howto = howto_table + 14;
      break;
    default:
      abort ();
      break;
    }
}

#define RTYPE2HOWTO(internal, relocentry) rtype2howto(internal,relocentry)


/* Perform any necessaru magic to the addend in a reloc entry */


#define CALC_ADDEND(abfd, symbol, ext_reloc, cache_ptr) \
 cache_ptr->addend =  ext_reloc.r_offset;


#define RELOC_PROCESSING(relent,reloc,symbols,abfd,section) \
 reloc_processing(relent, reloc, symbols, abfd, section)

static void
reloc_processing (relent, reloc, symbols, abfd, section)
     arelent * relent;
     struct internal_reloc *reloc;
     asymbol ** symbols;
     bfd * abfd;
     asection * section;
{
  relent->address = reloc->r_vaddr;
  rtype2howto (relent, reloc);

  if (((int) reloc->r_symndx) > 0)
    {
      relent->sym_ptr_ptr = symbols + obj_convert (abfd)[reloc->r_symndx];
    }
  else
    {
      relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
    }



  relent->addend = reloc->r_offset;

  relent->address -= section->vma;
  /*  relent->section = 0;*/
}


static int
h8300_reloc16_estimate(abfd, input_section, reloc, shrink, link_info)
     bfd *abfd;
     asection *input_section;
     arelent *reloc;
     unsigned int shrink;
     struct bfd_link_info *link_info;
{
  bfd_vma value;  
  bfd_vma dot;
  bfd_vma gap;

  /* The address of the thing to be relocated will have moved back by 
   the size of the shrink  - but we don't change reloc->address here,
   since we need it to know where the relocation lives in the source
   uncooked section */

  /*  reloc->address -= shrink;   conceptual */

  bfd_vma address = reloc->address - shrink;
  

  switch (reloc->howto->type)
    {     
    case R_MOVB2:
    case R_JMP2:
      shrink+=2;
      break;

      /* Thing is a move one byte */
    case R_MOVB1:
      value = bfd_coff_reloc16_get_value(reloc, link_info, input_section);

      if (value >= 0xff00)
	{ 

	  /* Change the reloc type from 16bit, possible 8 to 8bit
	     possible 16 */
	  reloc->howto = reloc->howto + 1;	  
	  /* The place to relc moves back by one */
	  /* This will be two bytes smaller in the long run */
	  shrink +=2 ;
	  bfd_perform_slip(abfd, 2, input_section, address);
	}      

      break;
      /* This is the 24 bit branch which could become an 8 bitter, 
       the relocation points to the first byte of the insn, not the
       actual data */

    case R_JMPL1:
      value = bfd_coff_reloc16_get_value(reloc, link_info, input_section);
	
      dot = input_section->output_section->vma +
	input_section->output_offset + address;
  
      /* See if the address we're looking at within 127 bytes of where
	 we are, if so then we can use a small branch rather than the
	 jump we were going to */

      gap = value - dot ;
  
      if (-120 < (long)gap && (long)gap < 120 )
	{ 

	  /* Change the reloc type from 24bit, possible 8 to 8bit
	     possible 32 */
	  reloc->howto = reloc->howto + 1;	  
	  /* This will be two bytes smaller in the long run */
	  shrink +=2 ;
	  bfd_perform_slip(abfd, 2, input_section, address);
	}
      break;

    case R_JMP1:

      value = bfd_coff_reloc16_get_value(reloc, link_info, input_section);
	
      dot = input_section->output_section->vma +
	input_section->output_offset + address;
  
      /* See if the address we're looking at within 127 bytes of where
	 we are, if so then we can use a small branch rather than the
	 jump we were going to */

      gap = value - (dot - shrink);
  

      if (-120 < (long)gap && (long)gap < 120 )
	{ 

	  /* Change the reloc type from 16bit, possible 8 to 8bit
	     possible 16 */
	  reloc->howto = reloc->howto + 1;	  
	  /* The place to relc moves back by one */

	  /* This will be two bytes smaller in the long run */
	  shrink +=2 ;
	  bfd_perform_slip(abfd, 2, input_section, address);
	}
      break;
    }

  
  return shrink;
}


/* First phase of a relaxing link */

/* Reloc types
   large		small
   R_MOVB1		R_MOVB2		mov.b with 16bit or 8 bit address
   R_JMP1		R_JMP2		jmp or pcrel branch
   R_JMPL1		R_JMPL_B8	24jmp or pcrel branch
   R_MOVLB1		R_MOVLB2	24 or 8 bit reloc for mov.b

*/

static void
h8300_reloc16_extra_cases (abfd, link_info, link_order, reloc, data, src_ptr,
			   dst_ptr)
     bfd *abfd;
     struct bfd_link_info *link_info;
     struct bfd_link_order *link_order;
     arelent *reloc;
     bfd_byte *data;
     unsigned int *src_ptr;
     unsigned int *dst_ptr;
{
  unsigned int src_address = *src_ptr;
  unsigned int dst_address = *dst_ptr;
  asection *input_section = link_order->u.indirect.section;

  switch (reloc->howto->type)
    {
      /* A 24 bit branch which could be a 8 bit pcrel, really pointing to
	 the byte before the 24bit hole, so we can treat it as a 32bit pointer */
    case R_PCRBYTE:
      {
	bfd_vma dot = link_order->offset 
	  + dst_address 
	    + link_order->u.indirect.section->output_section->vma;
	int gap = (bfd_coff_reloc16_get_value (reloc, link_info, input_section)
		   - dot);
	if (gap > 127 || gap < -128)
	  {
	    if (! ((*link_info->callbacks->reloc_overflow)
		   (link_info, bfd_asymbol_name (*reloc->sym_ptr_ptr),
		    reloc->howto->name, reloc->addend, input_section->owner,
		    input_section, reloc->address)))
	      abort ();
	  }
	gap &= ~1;
	bfd_put_8 (abfd, gap, data + dst_address);
	dst_address++;
	src_address++;

	break;
      }
    case R_PCRWORD:
      {
	bfd_vma dot = link_order->offset 
	  + dst_address 
	    + link_order->u.indirect.section->output_section->vma;
	int gap = (bfd_coff_reloc16_get_value (reloc, link_info, input_section)
		   - dot) - 1;
	if (gap > 32767 || gap < -32768)
	  {
	    if (! ((*link_info->callbacks->reloc_overflow)
		   (link_info, bfd_asymbol_name (*reloc->sym_ptr_ptr),
		    reloc->howto->name, reloc->addend, input_section->owner,
		    input_section, reloc->address)))
	      abort ();
	  }

	bfd_put_16 (abfd, gap, data + dst_address);
	dst_address+=2;
	src_address+=2;

	break;
      }

    case R_MEM_INDIRECT: 	/* Temporary  */
    case R_RELBYTE:
      {
	unsigned int gap = bfd_coff_reloc16_get_value (reloc, link_info,
						       input_section);
	if (gap < 0xff 
	    || (gap >= 0x0000ff00
	        && gap <= 0x0000ffff)
  	    || (   gap >= 0x00ffff00 
		&& gap <= 0x00ffffff)
	    || (   gap >= 0xffffff00
		&& gap <= 0xffffffff))
	  {
	    bfd_put_8 (abfd, gap, data + dst_address);
	    dst_address += 1;
	    src_address += 1;
	  }
	else
	  {
	    if (! ((*link_info->callbacks->reloc_overflow)
		   (link_info, bfd_asymbol_name (*reloc->sym_ptr_ptr),
		    reloc->howto->name, reloc->addend, input_section->owner,
		    input_section, reloc->address)))
	      abort ();
	  }
      }
      break;
    case R_JMP1:
      /* A relword which would have like to have been a pcrel */
    case R_MOVB1:
      /* A relword which would like to have been modified but
	     didn't make it */
    case R_RELWORD:
      bfd_put_16 (abfd,
		  bfd_coff_reloc16_get_value (reloc, link_info, input_section),
		  data + dst_address);
      dst_address += 2;
      src_address += 2;
      break;
    case R_RELLONG:
      bfd_put_32 (abfd,
		  bfd_coff_reloc16_get_value (reloc, link_info, input_section),
		  data + dst_address);
      dst_address += 4;
      src_address += 4;
      break;

    case R_MOVB2:
      /* Special relaxed type, there will be a gap between where we
	     get stuff from and where we put stuff to now
	
	     for a mov.b @aa:16 -> mov.b @aa:8
	     opcode 0x6a 0x0y offset
	     ->     0x2y off
	     */
      if (data[dst_address - 1] != 0x6a)
	abort ();
      switch (data[src_address] & 0xf0)
	{
	case 0x00:
	  /* Src is memory */
	  data[dst_address - 1] = (data[src_address] & 0xf) | 0x20;
	  break;
	case 0x80:
	  /* Src is reg */
	  data[dst_address - 1] = (data[src_address] & 0xf) | 0x30;
	  break;
	default:
	  abort ();
	}

      /* the offset must fit ! after all, what was all the relaxing
	     about ? */

      bfd_put_8 (abfd,
		 bfd_coff_reloc16_get_value (reloc, link_info, input_section),
		 data + dst_address);

      /* Note the magic - src goes up by two bytes, but dst by only
	     one */
      dst_address += 1;
      src_address += 3;

      break;

    case R_JMP2:
      
      /* Speciial relaxed type */
      {
	bfd_vma dot = link_order->offset
	+ dst_address
	+ link_order->u.indirect.section->output_section->vma;

	int gap = (bfd_coff_reloc16_get_value (reloc, link_info, input_section)
		   - dot - 1);

	if ((gap & ~0xff) != 0 && ((gap & 0xff00) != 0xff00))
	  abort ();

	bfd_put_8 (abfd, gap, data + dst_address);

	switch (data[dst_address - 1])
	  {
	  case 0x5e:
	    /* jsr -> bsr */
	    bfd_put_8 (abfd, 0x55, data + dst_address - 1);
	    break;
	  case 0x5a:
	    /* jmp ->bra */
	    bfd_put_8 (abfd, 0x40, data + dst_address - 1);
	    break;

	  default:
	    abort ();
	  }
	dst_address++;
	src_address += 3;

	break;
      }
      break;
      
    case R_JMPL_B8: /* 24 bit branch which is now 8 bits */
      
      /* Speciial relaxed type */
      {
	bfd_vma dot = link_order->offset
	+ dst_address
	+ link_order->u.indirect.section->output_section->vma;

	int gap = (bfd_coff_reloc16_get_value (reloc, link_info, input_section)
		   - dot - 2);

	if ((gap & ~0xff) != 0 && ((gap & 0xff00) != 0xff00))
	  abort ();

	switch (data[src_address])
	  {
	  case 0x5e:
	    /* jsr -> bsr */
	    bfd_put_8 (abfd, 0x55, data + dst_address);
	    break;
	  case 0x5a:
	    /* jmp ->bra */
	    bfd_put_8 (abfd, 0x40, data + dst_address);
	    break;

	  default:
	    bfd_put_8 (abfd, 0xde, data + dst_address);
	    break;
	  }

	bfd_put_8 (abfd, gap, data + dst_address + 1);
	dst_address += 2;
	src_address += 4;

	break;
      }

    case R_JMPL1:
      {
	int v = bfd_coff_reloc16_get_value (reloc, link_info, input_section);
	int o = bfd_get_32 (abfd, data + src_address);
	v = (v & 0x00ffffff) | (o & 0xff000000);
	bfd_put_32 (abfd, v, data + dst_address);
	dst_address += 4;
	src_address += 4;
      }

      break;


      /* A 24 bit mov  which could be an 8 bit move, really pointing to
	 the byte before the 24bit hole, so we can treat it as a 32bit pointer */
    case R_MOVLB1:
      {
	int v = bfd_coff_reloc16_get_value (reloc, link_info, input_section);
	int o = bfd_get_32 (abfd, data + dst_address);
	v = (v & 0x00ffffff) | (o & 0xff000000);
	bfd_put_32 (abfd, v, data + dst_address);
	dst_address += 4;
	src_address += 4;
      }

      break;
    default:

      abort ();
      break;

    }
  *src_ptr = src_address;
  *dst_ptr = dst_address;

}

#define coff_reloc16_extra_cases h8300_reloc16_extra_cases
#define coff_reloc16_estimate h8300_reloc16_estimate

#define COFF_LONG_FILENAMES
#include "coffcode.h"


#undef coff_bfd_get_relocated_section_contents
#undef coff_bfd_relax_section
#define coff_bfd_get_relocated_section_contents \
  bfd_coff_reloc16_get_relocated_section_contents
#define coff_bfd_relax_section bfd_coff_reloc16_relax_section



const bfd_target h8300coff_vec =
{
  "coff-h8300",			/* name */
  bfd_target_coff_flavour,
  BFD_ENDIAN_BIG,		/* data byte order is big */
  BFD_ENDIAN_BIG,		/* header byte order is big */

  (HAS_RELOC | EXEC_P |		/* object flags */
   HAS_LINENO | HAS_DEBUG |
   HAS_SYMS | HAS_LOCALS | WP_TEXT | BFD_IS_RELAXABLE ),
  (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC),	/* section flags */
  '_',				/* leading char */
  '/',				/* ar_pad_char */
  15,				/* ar_max_namelen */
  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
  bfd_getb32, bfd_getb_signed_32, bfd_putb32,
  bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
  bfd_getb32, bfd_getb_signed_32, bfd_putb32,
  bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* hdrs */

  {_bfd_dummy_target, coff_object_p,	/* bfd_check_format */
   bfd_generic_archive_p, _bfd_dummy_target},
  {bfd_false, coff_mkobject, _bfd_generic_mkarchive,	/* bfd_set_format */
   bfd_false},
  {bfd_false, coff_write_object_contents,	/* bfd_write_contents */
   _bfd_write_archive_contents, bfd_false},

     BFD_JUMP_TABLE_GENERIC (coff),
     BFD_JUMP_TABLE_COPY (coff),
     BFD_JUMP_TABLE_CORE (_bfd_nocore),
     BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
     BFD_JUMP_TABLE_SYMBOLS (coff),
     BFD_JUMP_TABLE_RELOCS (coff),
     BFD_JUMP_TABLE_WRITE (coff),
     BFD_JUMP_TABLE_LINK (coff),
     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),

  COFF_SWAP_TABLE,
};