path: root/gas/config/obj-bout.c

/* b.out object file format
   Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1996, 2000
   Free Software Foundation, Inc.

   This file is part of GAS, the GNU Assembler.

   GAS 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,
   or (at your option) any later version.

   GAS 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 GAS; see the file COPYING.  If not, write to the Free
   Software Foundation, 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.  */

#include "as.h"
#include "obstack.h"

/* In: segT   Out: N_TYPE bits  */
const short seg_N_TYPE[] =
{
  N_ABS,
  N_TEXT,
  N_DATA,
  N_BSS,
  N_UNDF,			/* unknown  */
  N_UNDF,			/* error  */
  N_UNDF,			/* expression  */
  N_UNDF,			/* debug  */
  N_UNDF,			/* ntv  */
  N_UNDF,			/* ptv  */
  N_REGISTER,			/* register  */
};

const segT N_TYPE_seg[N_TYPE + 2] =
{				/* N_TYPE == 0x1E = 32-2  */
  SEG_UNKNOWN,			/* N_UNDF == 0  */
  SEG_GOOF,
  SEG_ABSOLUTE,			/* N_ABS == 2  */
  SEG_GOOF,
  SEG_TEXT,			/* N_TEXT == 4  */
  SEG_GOOF,
  SEG_DATA,			/* N_DATA == 6  */
  SEG_GOOF,
  SEG_BSS,			/* N_BSS == 8  */
  SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_REGISTER,			/* dummy N_REGISTER for regs = 30  */
  SEG_GOOF,
};

static void obj_bout_line PARAMS ((int));

const pseudo_typeS obj_pseudo_table[] =
{
  {"line", obj_bout_line, 0},	/* Source code line number.  */

/* coff debugging directives.  Currently ignored silently.  */
  {"def", s_ignore, 0},
  {"dim", s_ignore, 0},
  {"endef", s_ignore, 0},
  {"ln", s_ignore, 0},
  {"scl", s_ignore, 0},
  {"size", s_ignore, 0},
  {"tag", s_ignore, 0},
  {"type", s_ignore, 0},
  {"val", s_ignore, 0},

/* other stuff we don't handle */
  {"ABORT", s_ignore, 0},
  {"ident", s_ignore, 0},

  {NULL}			/* End sentinel.  */
};

/* Relocation.  */

/* Crawl along a fixS chain. Emit the segment's relocations.  */

void
obj_emit_relocations (where, fixP, segment_address_in_file)
     char **where;
     fixS *fixP;		/* Fixup chain for this segment.  */
     relax_addressT segment_address_in_file;
{
  for (; fixP; fixP = fixP->fx_next)
    {
      if (fixP->fx_done == 0
	  || fixP->fx_r_type != NO_RELOC)
	{
	  symbolS *sym;

	  sym = fixP->fx_addsy;
	  while (sym->sy_value.X_op == O_symbol
		 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
	    sym = sym->sy_value.X_add_symbol;
	  fixP->fx_addsy = sym;

	  tc_bout_fix_to_chars (*where, fixP, segment_address_in_file);
	  *where += sizeof (struct relocation_info);
	}			/* if there's a symbol  */
    }				/* for each fixup  */
}

/* Aout file generation & utilities .  */

/* Convert a lvalue to machine dependent data.  */

void
obj_header_append (where, headers)
     char **where;
     object_headers *headers;
{
  /* Always leave in host byte order.  */

  headers->header.a_talign = section_alignment[SEG_TEXT];

  /* Force to at least 2.  */
  if (headers->header.a_talign < 2)
    {
      headers->header.a_talign = 2;
    }

  headers->header.a_dalign = section_alignment[SEG_DATA];
  headers->header.a_balign = section_alignment[SEG_BSS];

  headers->header.a_tload = 0;
  headers->header.a_dload =
    md_section_align (SEG_DATA, H_GET_TEXT_SIZE (headers));

  headers->header.a_relaxable = linkrelax;

#ifdef CROSS_COMPILE
  md_number_to_chars (*where, headers->header.a_magic, sizeof (headers->header.a_magic));
  *where += sizeof (headers->header.a_magic);
  md_number_to_chars (*where, headers->header.a_text, sizeof (headers->header.a_text));
  *where += sizeof (headers->header.a_text);
  md_number_to_chars (*where, headers->header.a_data, sizeof (headers->header.a_data));
  *where += sizeof (headers->header.a_data);
  md_number_to_chars (*where, headers->header.a_bss, sizeof (headers->header.a_bss));
  *where += sizeof (headers->header.a_bss);
  md_number_to_chars (*where, headers->header.a_syms, sizeof (headers->header.a_syms));
  *where += sizeof (headers->header.a_syms);
  md_number_to_chars (*where, headers->header.a_entry, sizeof (headers->header.a_entry));
  *where += sizeof (headers->header.a_entry);
  md_number_to_chars (*where, headers->header.a_trsize, sizeof (headers->header.a_trsize));
  *where += sizeof (headers->header.a_trsize);
  md_number_to_chars (*where, headers->header.a_drsize, sizeof (headers->header.a_drsize));
  *where += sizeof (headers->header.a_drsize);
  md_number_to_chars (*where, headers->header.a_tload, sizeof (headers->header.a_tload));
  *where += sizeof (headers->header.a_tload);
  md_number_to_chars (*where, headers->header.a_dload, sizeof (headers->header.a_dload));
  *where += sizeof (headers->header.a_dload);
  md_number_to_chars (*where, headers->header.a_talign, sizeof (headers->header.a_talign));
  *where += sizeof (headers->header.a_talign);
  md_number_to_chars (*where, headers->header.a_dalign, sizeof (headers->header.a_dalign));
  *where += sizeof (headers->header.a_dalign);
  md_number_to_chars (*where, headers->header.a_balign, sizeof (headers->header.a_balign));
  *where += sizeof (headers->header.a_balign);
  md_number_to_chars (*where, headers->header.a_relaxable, sizeof (headers->header.a_relaxable));
  *where += sizeof (headers->header.a_relaxable);
#else /* ! CROSS_COMPILE */
  append (where, (char *) &headers->header, sizeof (headers->header));
#endif /* ! CROSS_COMPILE */
}

void
obj_symbol_to_chars (where, symbolP)
     char **where;
     symbolS *symbolP;
{
  md_number_to_chars ((char *) &(S_GET_OFFSET (symbolP)),
		      S_GET_OFFSET (symbolP),
		      sizeof (S_GET_OFFSET (symbolP)));

  md_number_to_chars ((char *) &(S_GET_DESC (symbolP)),
		      S_GET_DESC (symbolP),
		      sizeof (S_GET_DESC (symbolP)));

  md_number_to_chars ((char *) &symbolP->sy_symbol.n_value,
		      S_GET_VALUE (symbolP),
		      sizeof (symbolP->sy_symbol.n_value));

  append (where, (char *) &symbolP->sy_symbol, sizeof (obj_symbol_type));
}

void
obj_emit_symbols (where, symbol_rootP)
     char **where;
     symbolS *symbol_rootP;
{
  symbolS *symbolP;

  /* Emit all symbols left in the symbol chain.  */
  for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
    {
      /* Used to save the offset of the name.  It is used to point to
	 the string in memory but must be a file offset.  */
      char *temp;

      temp = S_GET_NAME (symbolP);
      S_SET_OFFSET (symbolP, symbolP->sy_name_offset);

      /* Any symbol still undefined and is not a dbg symbol is made N_EXT.  */
      if (!S_IS_DEBUG (symbolP) && !S_IS_DEFINED (symbolP))
	S_SET_EXTERNAL (symbolP);

      obj_symbol_to_chars (where, symbolP);
      S_SET_NAME (symbolP, temp);
    }
}

void
obj_symbol_new_hook (symbolP)
     symbolS *symbolP;
{
  S_SET_OTHER (symbolP, 0);
  S_SET_DESC (symbolP, 0);
}

static void
obj_bout_line (ignore)
     int ignore;
{
  /* Assume delimiter is part of expression.  */
  /* BSD4.2 as fails with delightful bug, so we are not being
     incompatible here.  */
  new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
  demand_empty_rest_of_line ();
}

void
obj_read_begin_hook ()
{
}

void
obj_crawl_symbol_chain (headers)
     object_headers *headers;
{
  symbolS **symbolPP;
  symbolS *symbolP;
  int symbol_number = 0;

  tc_crawl_symbol_chain (headers);

  symbolPP = &symbol_rootP;	/* -> last symbol chain link.  */
  while ((symbolP = *symbolPP) != NULL)
    {
      if (flag_readonly_data_in_text && (S_GET_SEGMENT (symbolP) == SEG_DATA))
	{
	  S_SET_SEGMENT (symbolP, SEG_TEXT);
	}			/* if pusing data into text  */

      resolve_symbol_value (symbolP, 1);

      /* Skip symbols which were equated to undefined or common
	 symbols.  */
      if (symbolP->sy_value.X_op == O_symbol
	  && (! S_IS_DEFINED (symbolP) || S_IS_COMMON (symbolP)))
	{
	  *symbolPP = symbol_next (symbolP);
	  continue;
	}

      /* OK, here is how we decide which symbols go out into the
	 brave new symtab.  Symbols that do are:

	 * symbols with no name (stabd's?)
	 * symbols with debug info in their N_TYPE

	 Symbols that don't are:
	 * symbols that are registers
	 * symbols with \1 as their 3rd character (numeric labels)
	 * "local labels" as defined by S_LOCAL_NAME(name)
	 if the -L switch was passed to gas.

	 All other symbols are output.  We complain if a deleted
	 symbol was marked external.  */

      if (1
	  && !S_IS_REGISTER (symbolP)
	  && (!S_GET_NAME (symbolP)
	      || S_IS_DEBUG (symbolP)
#ifdef TC_I960
      /* FIXME-SOON this ifdef seems highly dubious to me.  xoxorich.  */
	      || !S_IS_DEFINED (symbolP)
	      || S_IS_EXTERNAL (symbolP)
#endif /* TC_I960 */
	      || (S_GET_NAME (symbolP)[0] != '\001'
		  && (flag_keep_locals || !S_LOCAL_NAME (symbolP)))))
	{
	  symbolP->sy_number = symbol_number++;

	  /* The + 1 after strlen account for the \0 at the end of
	     each string.  */
	  if (!S_IS_STABD (symbolP))
	    {
	      /* Ordinary case.  */
	      symbolP->sy_name_offset = string_byte_count;
	      string_byte_count += strlen (S_GET_NAME (symbolP)) + 1;
	    }
	  else			/* .Stabd case.  */
	    symbolP->sy_name_offset = 0;
	  symbolPP = &(symbolP->sy_next);
	}
      else
	{
	  if (S_IS_EXTERNAL (symbolP) || !S_IS_DEFINED (symbolP))
	    {
	      as_bad (_("Local symbol %s never defined"),
		      S_GET_NAME (symbolP));
	    }			/* Oops.  */

	  /* Unhook it from the chain.  */
	  *symbolPP = symbol_next (symbolP);
	}			/* if this symbol should be in the output  */
    }				/* for each symbol  */

  H_SET_SYMBOL_TABLE_SIZE (headers, symbol_number);
}

/* Find strings by crawling along symbol table chain.  */

void
obj_emit_strings (where)
     char **where;
{
  symbolS *symbolP;

#ifdef CROSS_COMPILE
  /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */
  md_number_to_chars (*where, string_byte_count, sizeof (string_byte_count));
  *where += sizeof (string_byte_count);
#else /* CROSS_COMPILE */
  append (where, (char *) &string_byte_count,
	  (unsigned long) sizeof (string_byte_count));
#endif /* CROSS_COMPILE */

  for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
    {
      if (S_GET_NAME (symbolP))
	append (where, S_GET_NAME (symbolP),
		(unsigned long) (strlen (S_GET_NAME (symbolP)) + 1));
    }				/* Walk symbol chain.  */
}