coff-mcore.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 585 行 · 第 1/2 页

/* BFD back-end for Motorola MCore COFF/PE
   Copyright 1999, 2000, 2001 Free Software Foundation, Inc.

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, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "coff/mcore.h"
#include "coff/internal.h"
#include "coff/pe.h"
#include "libcoff.h"

#ifdef BADMAG
#undef BADMAG
#endif
#define BADMAG(x) MCOREBADMAG(x)

#ifndef NUM_ELEM
#define NUM_ELEM(A) (sizeof (A) / sizeof (A)[0])
#endif

/* This file is compiled more than once, but we only compile the
   final_link routine once.  */
extern boolean mcore_bfd_coff_final_link
  PARAMS ((bfd *, struct bfd_link_info *));

static struct bfd_link_hash_table * coff_mcore_link_hash_table_create
  PARAMS ((bfd *));
static bfd_reloc_status_type        mcore_coff_unsupported_reloc
  PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
static boolean                      coff_mcore_relocate_section
  PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
	   struct internal_reloc *, struct internal_syment *, asection **));
static reloc_howto_type *           mcore_coff_reloc_type_lookup
  PARAMS ((bfd *, bfd_reloc_code_real_type));
static reloc_howto_type *           coff_mcore_rtype_to_howto
  PARAMS ((bfd *, asection *, struct internal_reloc *,
	   struct coff_link_hash_entry *, struct internal_syment *, bfd_vma *));

/* The NT loader points the toc register to &toc + 32768, in order to
   use the complete range of a 16-bit displacement. We have to adjust
   for this when we fix up loads displaced off the toc reg.  */
#define TOC_LOAD_ADJUSTMENT (-32768)
#define TOC_SECTION_NAME ".private.toc"

/* The main body of code is in coffcode.h.  */
#define COFF_DEFAULT_SECTION_ALIGNMENT_POWER 2

/* In case we're on a 32-bit machine, construct a 64-bit "-1" value
   from smaller values.  Start with zero, widen, *then* decrement.  */
#define MINUS_ONE	(((bfd_vma)0) - 1)

static reloc_howto_type mcore_coff_howto_table[] =
{
  /* Unused: */
  HOWTO (IMAGE_REL_MCORE_ABSOLUTE,/* type */
	 0,	                 /* rightshift */
	 0,	                 /* size (0 = byte, 1 = short, 2 = long) */
	 0,	                 /* bitsize */
	 false,	                 /* pc_relative */
	 0,	                 /* bitpos */
	 complain_overflow_dont, /* dont complain_on_overflow */
	 NULL,		         /* special_function */
	 "ABSOLUTE",             /* name */
	 false,	                 /* partial_inplace */
	 0x00,	 	         /* src_mask */
	 0x00,        		 /* dst_mask */
	 false),                 /* pcrel_offset */

  HOWTO (IMAGE_REL_MCORE_ADDR32,/* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 NULL,		        /* special_function */
	 "ADDR32",              /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,            /* src_mask */
	 0xffffffff,            /* dst_mask */
	 false),                /* pcrel_offset */

  /* 8 bits + 2 zero bits; jmpi/jsri/lrw instructions.
     Should not appear in object files.  */
  HOWTO (IMAGE_REL_MCORE_PCREL_IMM8BY4,	/* type */
	 2,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 8,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 mcore_coff_unsupported_reloc, /* special_function */
	 "IMM8BY4",             /* name */
	 false,			/* partial_inplace */
	 0,			/* src_mask */
	 0,			/* dst_mask */
	 true),			/* pcrel_offset */

  /* bsr/bt/bf/br instructions; 11 bits + 1 zero bit
     Span 2k instructions == 4k bytes.
     Only useful pieces at the relocated address are the opcode (5 bits) */
  HOWTO (IMAGE_REL_MCORE_PCREL_IMM11BY2,/* type */
	 1,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 11,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 NULL,	                /* special_function */
	 "IMM11BY2",            /* name */
	 false,			/* partial_inplace */
	 0x0,			/* src_mask */
	 0x7ff,			/* dst_mask */
	 true),			/* pcrel_offset */

  /* 4 bits + 1 zero bit; 'loopt' instruction only; unsupported.  */
  HOWTO (IMAGE_REL_MCORE_PCREL_IMM4BY2,	/* type */
	 1,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 4,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 mcore_coff_unsupported_reloc, /* special_function */
	 "IMM4BY2",              /* name */
	 false,			/* partial_inplace */
	 0,			/* src_mask */
	 0,			/* dst_mask */
	 true),			/* pcrel_offset */

  /* 32-bit pc-relative. Eventually this will help support PIC code.  */
  HOWTO (IMAGE_REL_MCORE_PCREL_32,/* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 32,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 NULL,	                /* special_function */
	 "PCREL_32",	        /* name */
	 false,			/* partial_inplace */
	 0x0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 true),			/* pcrel_offset */

  /* Like PCREL_IMM11BY2, this relocation indicates that there is a
     'jsri' at the specified address. There is a separate relocation
     entry for the literal pool entry that it references, but we
     might be able to change the jsri to a bsr if the target turns out
     to be close enough [even though we won't reclaim the literal pool
     entry, we'll get some runtime efficiency back]. Note that this
     is a relocation that we are allowed to safely ignore.  */
  HOWTO (IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2,/* type */
	 1,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 11,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 NULL,	                /* special_function */
	 "JSR_IMM11BY2",        /* name */
	 false,			/* partial_inplace */
	 0x0,			/* src_mask */
	 0x7ff,			/* dst_mask */
	 true),			/* pcrel_offset */

  HOWTO (IMAGE_REL_MCORE_RVA,   /* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 32,			/* bitsize */
	 false,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 NULL,                  /* special_function */
	 "MCORE_RVA",           /* name */
	 true,			/* partial_inplace */
	 0xffffffff,		/* src_mask */
	 0xffffffff,		/* dst_mask */
	 true)			/* pcrel_offset */
};

/* Extend the coff_link_hash_table structure with a few M*Core specific fields.
   This allows us to store global data here without actually creating any
   global variables, which is a no-no in the BFD world.  */
typedef struct coff_mcore_link_hash_table
{
  /* The original coff_link_hash_table structure.  MUST be first field.  */
  struct coff_link_hash_table	root;

  bfd *                         bfd_of_toc_owner;
  long int                      global_toc_size;
  long int                      import_table_size;
  long int                      first_thunk_address;
  long int                      thunk_size;
}
mcore_hash_table;

/* Get the MCore coff linker hash table from a link_info structure.  */
#define coff_mcore_hash_table(info) \
  ((mcore_hash_table *) ((info)->hash))

/* Create an MCore coff linker hash table.  */
static struct bfd_link_hash_table *
coff_mcore_link_hash_table_create (abfd)
     bfd * abfd;
{
  mcore_hash_table * ret;

  ret = ((mcore_hash_table *) bfd_alloc (abfd, sizeof (* ret)));
  if (ret == (mcore_hash_table *) NULL)
    return NULL;

  if (! _bfd_coff_link_hash_table_init
      (& ret->root, abfd, _bfd_coff_link_hash_newfunc))
    {
      bfd_release (abfd, ret);
      return (struct bfd_link_hash_table *) NULL;
    }

  ret->bfd_of_toc_owner = NULL;
  ret->global_toc_size  = 0;
  ret->import_table_size = 0;
  ret->first_thunk_address = 0;
  ret->thunk_size = 0;

  return & ret->root.root;
}

/* Add an entry to the base file.  */
static void
mcore_emit_base_file_entry (info, output_bfd, input_section, reloc_offset)
      struct bfd_link_info * info;
      bfd *                  output_bfd;
      asection *             input_section;
      bfd_vma                reloc_offset;
{
  bfd_vma addr = reloc_offset
                 - input_section->vma
                 + input_section->output_offset
                 + input_section->output_section->vma;

  if (coff_data (output_bfd)->pe)
     addr -= pe_data (output_bfd)->pe_opthdr.ImageBase;

  fwrite (&addr, 1, sizeof (addr), (FILE *) info->base_file);
}

static bfd_reloc_status_type
mcore_coff_unsupported_reloc (abfd, reloc_entry, symbol, data, input_section,
			   output_bfd, error_message)
     bfd * abfd;
     arelent * reloc_entry;
     asymbol * symbol ATTRIBUTE_UNUSED;
     PTR data ATTRIBUTE_UNUSED;
     asection * input_section ATTRIBUTE_UNUSED;
     bfd * output_bfd ATTRIBUTE_UNUSED;
     char ** error_message ATTRIBUTE_UNUSED;
{
  BFD_ASSERT (reloc_entry->howto != (reloc_howto_type *)0);

  _bfd_error_handler (_("%s: Relocation %s (%d) is not currently supported.\n"),
		      bfd_get_filename (abfd),
		      reloc_entry->howto->name,
		      reloc_entry->howto->type);

  return bfd_reloc_notsupported;
}

/* A cheesy little macro to make the code a little more readable.  */
#define HOW2MAP(bfd_rtype, mcore_rtype)  \
 case bfd_rtype: return & mcore_coff_howto_table [mcore_rtype]

static reloc_howto_type *
mcore_coff_reloc_type_lookup (abfd, code)
     bfd * abfd ATTRIBUTE_UNUSED;
     bfd_reloc_code_real_type code;