hp300hpux.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 855 行 · 第 1/2 页

/* BFD backend for hp-ux 9000/300
   Copyright 1990, 1991, 1993, 1994, 1995, 1997, 2000, 2001
   Free Software Foundation, Inc.
   Written by Glenn Engel.

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.  */

/*

    hpux native  ------------> |               |
                               | hp300hpux bfd | ----------> hpux w/gnu ext
    hpux w/gnu extension ----> |               |

    Support for the 9000/[34]00 has several limitations.
      1. Shared libraries are not supported.
      2. The output format from this bfd is not usable by native tools.

    The primary motivation for writing this bfd was to allow use of
    gdb and gcc for host based debugging and not to mimic the hp-ux tools
    in every detail.  This leads to a significant simplification of the
    code and a leap in performance.  The decision to not output hp native
    compatible objects was further strengthened by the fact that the richness
    of the gcc compiled objects could not be represented without loss of
    information.  For example, while the hp format supports the concept of
    secondary symbols, it does not support indirect symbols.  Another
    reason is to maintain backwards compatibility with older implementations
    of gcc on hpux which used 'hpxt' to translate .a and .o files into a
    format which could be readily understood by the gnu linker and gdb.
    This allows reading hp secondary symbols and converting them into
    indirect symbols but the reverse it not always possible.

    Another example of differences is that the hp format stores symbol offsets
    in the object code while the gnu utilities use a field in the
    relocation record for this.  To support the hp native format, the object
    code would need to be patched with the offsets when producing .o files.

    The basic technique taken in this implementation is to #include the code
    from aoutx.h and aout-target.h with appropriate #defines to override
    code where a unique implementation is needed:

    {
        #define a bunch of stuff
        #include <aoutx.h>

        implement a bunch of functions

        #include "aout-target.h"
    }

    The hp symbol table is a bit different than other a.out targets.  Instead
    of having an array of nlist items and an array of strings, hp's format
    has them mixed together in one structure.  In addition, the strings are
    not null terminated.  It looks something like this:

    nlist element 1
    string1
    nlist element 2
    string2
    ...

    The whole symbol table is read as one chunk and then we march thru it
    and convert it to canonical form.  As we march thru the table, we copy
    the nlist data into the internal form and we compact the strings and null
    terminate them, using storage from the already allocated symbol table:

    string1
    null
    string2
    null
 */

/* @@ Is this really so different from normal a.out that it needs to include
   aoutx.h?  We should go through this file sometime and see what can be made
   more dependent on aout32.o and what might need to be broken off and accessed
   through the backend_data field.  Or, maybe we really do need such a
   completely separate implementation.  I don't have time to investigate this
   much further right now.  [raeburn:19930428.2124EST] */
/* @@ Also, note that there wind up being two versions of some routines, with
   different names, only one of which actually gets used.  For example:
	slurp_symbol_table
	swap_std_reloc_in
	slurp_reloc_table
	get_symtab
	get_symtab_upper_bound
	canonicalize_reloc
	mkobject
   This should also be fixed.  */

#define TARGETNAME "a.out-hp300hpux"
#define MY(OP) CAT(hp300hpux_,OP)

#define external_exec hp300hpux_exec_bytes
#define external_nlist hp300hpux_nlist_bytes

#include "aout/hp300hpux.h"

/* define these so we can compile unused routines in aoutx.h */
#define e_strx  e_shlib
#define e_other e_length
#define e_desc  e_almod

#define AR_PAD_CHAR '/'
#define TARGET_IS_BIG_ENDIAN_P
#define DEFAULT_ARCH bfd_arch_m68k

#define MY_get_section_contents aout_32_get_section_contents
#define MY_slurp_armap bfd_slurp_bsd_armap_f2

/***********************************************/
/* provide overrides for routines in this file */
/***********************************************/
/* these don't use MY because that causes problems within JUMP_TABLE
   (CAT winds up being expanded recursively, which ANSI C compilers
   will not do).  */
#define MY_get_symtab hp300hpux_get_symtab
#define MY_get_symtab_upper_bound hp300hpux_get_symtab_upper_bound
#define MY_canonicalize_reloc hp300hpux_canonicalize_reloc
#define MY_write_object_contents hp300hpux_write_object_contents

#define MY_read_minisymbols _bfd_generic_read_minisymbols
#define MY_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol

#define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
#define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
#define MY_final_link_callback unused
#define MY_bfd_final_link _bfd_generic_final_link

/* Until and unless we convert the slurp_reloc and slurp_symtab
   routines in this file, we can not use the default aout
   free_cached_info routine which assumes that the relocs and symtabs
   were allocated using malloc.  */
#define MY_bfd_free_cached_info bfd_true

#define hp300hpux_write_syms aout_32_write_syms

#define MY_callback MY(callback)

#define MY_exec_hdr_flags 0x2

#define NAME_swap_exec_header_in NAME(hp300hpux_32_,swap_exec_header_in)

#define HP_SYMTYPE_UNDEFINED	0x00
#define HP_SYMTYPE_ABSOLUTE	0x01
#define HP_SYMTYPE_TEXT		0x02
#define HP_SYMTYPE_DATA		0x03
#define HP_SYMTYPE_BSS		0x04
#define HP_SYMTYPE_COMMON	0x05

#define HP_SYMTYPE_TYPE		0x0F
#define HP_SYMTYPE_FILENAME	0x1F

#define HP_SYMTYPE_ALIGN	0x10
#define HP_SYMTYPE_EXTERNAL	0x20
#define HP_SECONDARY_SYMBOL     0x40

/* RELOCATION DEFINITIONS */
#define HP_RSEGMENT_TEXT	0x00
#define HP_RSEGMENT_DATA	0x01
#define HP_RSEGMENT_BSS		0x02
#define HP_RSEGMENT_EXTERNAL	0x03
#define HP_RSEGMENT_PCREL       0x04
#define HP_RSEGMENT_RDLT        0x05
#define HP_RSEGMENT_RPLT        0x06
#define HP_RSEGMENT_NOOP	0x3F

#define HP_RLENGTH_BYTE		0x00
#define HP_RLENGTH_WORD		0x01
#define HP_RLENGTH_LONG		0x02
#define HP_RLENGTH_ALIGN	0x03

#define NAME(x,y) CAT3(hp300hpux,_32_,y)
#define ARCH_SIZE 32

/* aoutx.h requires definitions for BMAGIC and QMAGIC.  */
#define BMAGIC HPUX_DOT_O_MAGIC
#define QMAGIC 0314

#include "aoutx.h"

/* Since the hpux symbol table has nlist elements interspersed with
   strings and we need to insert som strings for secondary symbols, we
   give ourselves a little extra padding up front to account for
   this.  Note that for each non-secondary symbol we process, we gain
   9 bytes of space for the discarded nlist element (one byte used for
   null).  SYM_EXTRA_BYTES is the extra space.  */
#define SYM_EXTRA_BYTES   1024

/* Set parameters about this a.out file that are machine-dependent.
   This routine is called from some_aout_object_p just before it returns.  */
static const bfd_target *
MY (callback) (abfd)
     bfd *abfd;
{
  struct internal_exec *execp = exec_hdr (abfd);

  /* Calculate the file positions of the parts of a newly read aout header */
  obj_textsec (abfd)->_raw_size = N_TXTSIZE (*execp);

  /* The virtual memory addresses of the sections */
  obj_textsec (abfd)->vma = N_TXTADDR (*execp);
  obj_datasec (abfd)->vma = N_DATADDR (*execp);
  obj_bsssec (abfd)->vma = N_BSSADDR (*execp);

  obj_textsec (abfd)->lma = obj_textsec (abfd)->vma;
  obj_datasec (abfd)->lma = obj_datasec (abfd)->vma;
  obj_bsssec (abfd)->lma = obj_bsssec (abfd)->vma;

  /* The file offsets of the sections */
  obj_textsec (abfd)->filepos = N_TXTOFF (*execp);
  obj_datasec (abfd)->filepos = N_DATOFF (*execp);

  /* The file offsets of the relocation info */
  obj_textsec (abfd)->rel_filepos = N_TRELOFF (*execp);
  obj_datasec (abfd)->rel_filepos = N_DRELOFF (*execp);

  /* The file offsets of the string table and symbol table.  */
  obj_sym_filepos (abfd) = N_SYMOFF (*execp);
  obj_str_filepos (abfd) = N_STROFF (*execp);

  /* Determine the architecture and machine type of the object file.  */
#ifdef SET_ARCH_MACH
  SET_ARCH_MACH (abfd, *execp);
#else
  bfd_default_set_arch_mach (abfd, DEFAULT_ARCH, 0);
#endif

  if (obj_aout_subformat (abfd) == gnu_encap_format)
    {
      /* The file offsets of the relocation info */
      obj_textsec (abfd)->rel_filepos = N_GNU_TRELOFF (*execp);
      obj_datasec (abfd)->rel_filepos = N_GNU_DRELOFF (*execp);

      /* The file offsets of the string table and symbol table.  */
      obj_sym_filepos (abfd) = N_GNU_SYMOFF (*execp);
      obj_str_filepos (abfd) = (obj_sym_filepos (abfd) + execp->a_syms);

      abfd->flags |= HAS_LINENO | HAS_DEBUG | HAS_SYMS | HAS_LOCALS;
      bfd_get_symcount (abfd) = execp->a_syms / 12;
      obj_symbol_entry_size (abfd) = 12;
      obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
    }

  return abfd->xvec;
}

extern boolean aout_32_write_syms PARAMS ((bfd * abfd));

static boolean
MY (write_object_contents) (abfd)
     bfd *abfd;
{
  struct external_exec exec_bytes;
  struct internal_exec *execp = exec_hdr (abfd);
  bfd_size_type text_size;	/* dummy vars */
  file_ptr text_end;

  memset (&exec_bytes, 0, sizeof (exec_bytes));

  obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;

  if (adata (abfd).magic == undecided_magic)
    NAME (aout,adjust_sizes_and_vmas) (abfd, &text_size, &text_end);
  execp->a_syms = 0;

  execp->a_entry = bfd_get_start_address (abfd);

  execp->a_trsize = ((obj_textsec (abfd)->reloc_count) *
		     obj_reloc_entry_size (abfd));
  execp->a_drsize = ((obj_datasec (abfd)->reloc_count) *
		     obj_reloc_entry_size (abfd));

  N_SET_MACHTYPE (*execp, 0xc);
  N_SET_FLAGS (*execp, aout_backend_info (abfd)->exec_hdr_flags);

  NAME (aout,swap_exec_header_out) (abfd, execp, &exec_bytes);

  /* update fields not covered by default swap_exec_header_out */

  /* this is really the sym table size but we store it in drelocs */
  bfd_h_put_32 (abfd, bfd_get_symcount (abfd) * 12, exec_bytes.e_drelocs);

  if (bfd_seek (abfd, 0L, false) != 0
      || (bfd_write ((PTR) & exec_bytes, 1, EXEC_BYTES_SIZE, abfd)
	  != EXEC_BYTES_SIZE))
    return false;

  /* Write out the symbols, and then the relocs.  We must write out
       the symbols first so that we know the symbol indices.  */

  if (bfd_get_symcount (abfd) != 0)
    {
      /* Skip the relocs to where we want to put the symbols.  */
      if (bfd_seek (abfd, (file_ptr) N_DRELOFF (*execp) + execp->a_drsize,
		    SEEK_SET) != 0)
	return false;
    }

  if (!MY (write_syms) (abfd))
    return false;

  if (bfd_get_symcount (abfd) != 0)
    {
      if (bfd_seek (abfd, (long) (N_TRELOFF (*execp)), false) != 0)
	return false;
      if (!NAME (aout,squirt_out_relocs) (abfd, obj_textsec (abfd)))
	return false;
      if (bfd_seek (abfd, (long) (N_DRELOFF (*execp)), false) != 0)
	return false;
      if (!NAME (aout,squirt_out_relocs) (abfd, obj_datasec (abfd)))
	return false;
    }

  return true;
}

/* convert the hp symbol type to be the same as aout64.h usage so we */
/* can piggyback routines in aoutx.h.                                */

static void
convert_sym_type (sym_pointer, cache_ptr, abfd)
     struct external_nlist *sym_pointer ATTRIBUTE_UNUSED;
     aout_symbol_type *cache_ptr;
     bfd *abfd ATTRIBUTE_UNUSED;
{
  int name_type;
  int new_type;

  name_type = (cache_ptr->type);
  new_type = 0;

  if ((name_type & HP_SYMTYPE_ALIGN) != 0)
    {
      /* iou_error ("aligned symbol encountered: %s", name);*/
      name_type = 0;
    }

  if (name_type == HP_SYMTYPE_FILENAME)
    new_type = N_FN;
  else
    {
      switch (name_type & HP_SYMTYPE_TYPE)
	{
	case HP_SYMTYPE_UNDEFINED:
	  new_type = N_UNDF;
	  break;

	case HP_SYMTYPE_ABSOLUTE:
	  new_type = N_ABS;
	  break;

	case HP_SYMTYPE_TEXT:
	  new_type = N_TEXT;
	  break;

	case HP_SYMTYPE_DATA:
	  new_type = N_DATA;
	  break;

	case HP_SYMTYPE_BSS:
	  new_type = N_BSS;
	  break;

	case HP_SYMTYPE_COMMON:
	  new_type = N_COMM;
	  break;

	default:
	  abort ();
	  break;
	}
      if (name_type & HP_SYMTYPE_EXTERNAL)
	new_type |= N_EXT;

      if (name_type & HP_SECONDARY_SYMBOL)
	{
	  switch (new_type)
	    {
	    default:
	      abort ();
	    case N_UNDF | N_EXT:
	      /* If the value is nonzero, then just treat this as a
                 common symbol.  I don't know if this is correct in
                 all cases, but it is more correct than treating it as
                 a weak undefined symbol.  */
	      if (cache_ptr->symbol.value == 0)
		new_type = N_WEAKU;
	      break;
	    case N_ABS | N_EXT:
	      new_type = N_WEAKA;
	      break;
	    case N_TEXT | N_EXT:
	      new_type = N_WEAKT;
	      break;
	    case N_DATA | N_EXT:
	      new_type = N_WEAKD;
	      break;
	    case N_BSS | N_EXT:
	      new_type = N_WEAKB;
	      break;
	    }
	}
    }
  cache_ptr->type = new_type;

}

/*
DESCRIPTION
        Swaps the information in an executable header taken from a raw
        byte stream memory image, into the internal exec_header
        structure.
*/

void