nlm32-ppc.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 1,046 行 · 第 1/3 页

/* Support for 32-bit PowerPC NLM (NetWare Loadable Module)
   Copyright 1994, 1995, 2000 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, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"

/* The format of a PowerPC NLM changed.  Define OLDFORMAT to get the
   old format.  */

#define ARCH_SIZE 32

#include "nlm/ppc-ext.h"
#define Nlm_External_Fixed_Header	Nlm32_powerpc_External_Fixed_Header

#include "libnlm.h"

#ifdef OLDFORMAT
static boolean nlm_powerpc_backend_object_p
  PARAMS ((bfd *));
static boolean nlm_powerpc_write_prefix
  PARAMS ((bfd *));
#endif

static boolean nlm_powerpc_read_reloc
  PARAMS ((bfd *, nlmNAME(symbol_type) *, asection **, arelent *));
static boolean nlm_powerpc_mangle_relocs
  PARAMS ((bfd *, asection *, PTR, bfd_vma, bfd_size_type));
static boolean nlm_powerpc_read_import
  PARAMS ((bfd *, nlmNAME(symbol_type) *));

#ifdef OLDFORMAT
static boolean nlm_powerpc_write_reloc
  PARAMS ((bfd *, asection *, arelent *, int));
#endif

static boolean nlm_powerpc_write_import
  PARAMS ((bfd *, asection *, arelent *));
static boolean nlm_powerpc_write_external
  PARAMS ((bfd *, bfd_size_type, asymbol *, struct reloc_and_sec *));

#ifndef OLDFORMAT
static boolean nlm_powerpc_set_public_section
  PARAMS ((bfd *, nlmNAME(symbol_type) *));
static bfd_vma nlm_powerpc_get_public_offset
  PARAMS ((bfd *, asymbol *));
#endif

#ifdef OLDFORMAT

/* The prefix header is only used in the old format.  */

/* PowerPC NLM's have a prefix header before the standard NLM.  This
   function reads it in, verifies the version, and seeks the bfd to
   the location before the regular NLM header.  */

static boolean
nlm_powerpc_backend_object_p (abfd)
     bfd *abfd;
{
  struct nlm32_powerpc_external_prefix_header s;

  if (bfd_read ((PTR) &s, sizeof s, 1, abfd) != sizeof s)
    return false;

  if (memcmp (s.signature, NLM32_POWERPC_SIGNATURE, sizeof s.signature) != 0
      || bfd_h_get_32 (abfd, s.headerVersion) != NLM32_POWERPC_HEADER_VERSION)
    return false;

  return true;
}

/* Write out the prefix.  */

static boolean
nlm_powerpc_write_prefix (abfd)
     bfd *abfd;
{
  struct nlm32_powerpc_external_prefix_header s;

  memset (&s, 0, sizeof s);
  memcpy (s.signature, NLM32_POWERPC_SIGNATURE, sizeof s.signature);
  bfd_h_put_32 (abfd, (bfd_vma) NLM32_POWERPC_HEADER_VERSION, s.headerVersion);
  bfd_h_put_32 (abfd, (bfd_vma) 0, s.origins);

  /* FIXME: What should we do about the date?  */

  if (bfd_write ((PTR) &s, sizeof s, 1, abfd) != sizeof s)
    return false;

  return true;
}

#endif /* OLDFORMAT */

#ifndef OLDFORMAT

/* There is only one type of reloc in a PowerPC NLM.  */

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

/* Read a PowerPC NLM reloc.  */

static boolean
nlm_powerpc_read_reloc (abfd, sym, secp, rel)
     bfd *abfd;
     nlmNAME(symbol_type) *sym;
     asection **secp;
     arelent *rel;
{
  bfd_byte temp[4];
  bfd_vma val;
  const char *name;

  if (bfd_read (temp, sizeof (temp), 1, abfd) != sizeof (temp))
    return false;

  val = bfd_get_32 (abfd, temp);

  /* The value is a word offset into either the code or data segment.
     This is the location which needs to be adjusted.

     The high bit is 0 if the value is an offset into the data
     segment, or 1 if the value is an offset into the text segment.

     If this is a relocation fixup rather than an imported symbol (the
     sym argument is NULL), then the second most significant bit is 0
     if the address of the data segment should be added to the
     location addressed by the value, or 1 if the address of the text
     segment should be added.

     If this is an imported symbol, the second most significant bit is
     not used and must be 0.  */

  if ((val & NLM_HIBIT) == 0)
    name = NLM_INITIALIZED_DATA_NAME;
  else
    {
      name = NLM_CODE_NAME;
      val &=~ NLM_HIBIT;
    }
  *secp = bfd_get_section_by_name (abfd, name);

  if (sym == NULL)
    {
      if ((val & (NLM_HIBIT >> 1)) == 0)
	name = NLM_INITIALIZED_DATA_NAME;
      else
	{
	  name = NLM_CODE_NAME;
	  val &=~ (NLM_HIBIT >> 1);
	}
      rel->sym_ptr_ptr = bfd_get_section_by_name (abfd, name)->symbol_ptr_ptr;
    }

  rel->howto = &nlm_powerpc_howto;

  rel->address = val << 2;
  rel->addend = 0;

  return true;
}

#else /* OLDFORMAT */

/* This reloc handling is only applicable to the old format.  */

/* How to process the various reloc types.  PowerPC NLMs use XCOFF
   reloc types, and I have just copied the XCOFF reloc table here.  */

static reloc_howto_type nlm_powerpc_howto_table[] =
{
  /* Standard 32 bit relocation.  */
  HOWTO (0,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_POS",               /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,            /* src_mask */
	 0xffffffff,            /* dst_mask */
	 false),                /* pcrel_offset */

  /* 32 bit relocation, but store negative value.  */
  HOWTO (1,	                /* type */
	 0,	                /* rightshift */
	 -2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_NEG",               /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,            /* src_mask */
	 0xffffffff,            /* dst_mask */
	 false),                /* pcrel_offset */

  /* 32 bit PC relative relocation.  */
  HOWTO (2,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 true,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_REL",               /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,            /* src_mask */
	 0xffffffff,            /* dst_mask */
	 false),                /* pcrel_offset */

  /* 16 bit TOC relative relocation.  */
  HOWTO (3,	                /* type */
	 0,	                /* rightshift */
	 1,	                /* size (0 = byte, 1 = short, 2 = long) */
	 16,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_TOC",               /* name */
	 true,	                /* partial_inplace */
	 0xffff,	        /* src_mask */
	 0xffff,        	/* dst_mask */
	 false),                /* pcrel_offset */

  /* I don't really know what this is.  */
  HOWTO (4,	                /* type */
	 1,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_RTB",               /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,	        /* src_mask */
	 0xffffffff,        	/* dst_mask */
	 false),                /* pcrel_offset */

  /* External TOC relative symbol.  */
  HOWTO (5,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 16,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_GL",                /* name */
	 true,	                /* partial_inplace */
	 0xffff,	        /* src_mask */
	 0xffff,        	/* dst_mask */
	 false),                /* pcrel_offset */

  /* Local TOC relative symbol.  */
  HOWTO (6,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 16,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_TCL",               /* name */
	 true,	                /* partial_inplace */
	 0xffff,	        /* src_mask */
	 0xffff,        	/* dst_mask */
	 false),                /* pcrel_offset */

  { 7 },

  /* Non modifiable absolute branch.  */
  HOWTO (8,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 26,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_BA",                /* name */
	 true,	                /* partial_inplace */
	 0x3fffffc,	        /* src_mask */
	 0x3fffffc,        	/* dst_mask */
	 false),                /* pcrel_offset */

  { 9 },

  /* Non modifiable relative branch.  */
  HOWTO (0xa,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 26,	                /* bitsize */
	 true,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_BR",                /* name */
	 true,	                /* partial_inplace */
	 0x3fffffc,	        /* src_mask */
	 0x3fffffc,        	/* dst_mask */
	 false),                /* pcrel_offset */

  { 0xb },

  /* Indirect load.  */
  HOWTO (0xc,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 16,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */