binutils-gdb/gas/config/obj-aout.c

501 lines
14 KiB
C

/* a.out object file format
Copyright (C) 1989, 1990, 1991 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 1,
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, 675 Mass Ave, Cambridge, MA 02139, USA. */
/* $Id$ */
#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, /* absent */
N_UNDF, /* pass1 */
N_UNDF, /* error */
N_UNDF, /* bignum/flonum */
N_UNDF, /* difference */
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,
};
#ifdef __STDC__
static void obj_aout_stab(int what);
static void obj_aout_line(void);
static void obj_aout_desc(void);
#else /* __STDC__ */
static void obj_aout_desc();
static void obj_aout_stab();
static void obj_aout_line();
#endif /* __STDC__ */
const pseudo_typeS obj_pseudo_table[] = {
{ "line", obj_aout_line, 0 }, /* source code line number */
{ "ln", obj_aout_line, 0 }, /* source code line number */
{ "desc", obj_aout_desc, 0 }, /* def */
{ "stabd", obj_aout_stab, 'd' }, /* stabs */
{ "stabn", obj_aout_stab, 'n' }, /* stabs */
{ "stabs", obj_aout_stab, 's' }, /* stabs */
{ NULL} /* end sentinel */
}; /* obj_pseudo_table */
/* Relocation. */
/*
* In: length of relocation (or of address) in chars: 1, 2 or 4.
* Out: GNU LD relocation length code: 0, 1, or 2.
*/
static unsigned char
nbytes_r_length [] = {
42, 0, 1, 42, 2
};
/*
* emit_relocations()
*
* 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;
{
struct reloc_info_generic ri;
register symbolS *symbolP;
/* If a machine dependent emitter is needed, call it instead. */
if (md_emit_relocations) {
(*md_emit_relocations) (fixP, segment_address_in_file);
return;
}
/* JF this is for paranoia */
bzero((char *)&ri,sizeof(ri));
for (; fixP; fixP = fixP->fx_next) {
if ((symbolP = fixP->fx_addsy) != 0) {
ri.r_bsr = fixP->fx_bsr;
ri.r_disp = fixP->fx_im_disp;
ri.r_callj = fixP->fx_callj;
ri.r_length = nbytes_r_length [fixP->fx_size];
ri.r_pcrel = fixP->fx_pcrel;
ri.r_address = fixP->fx_frag->fr_address + fixP->fx_where - segment_address_in_file;
if (S_GET_TYPE(symbolP) == N_UNDF) {
ri.r_extern = 1;
ri.r_symbolnum = symbolP->sy_number;
} else {
ri.r_extern = 0;
ri.r_symbolnum = S_GET_TYPE(symbolP);
}
/* Output the relocation information in machine-dependent form. */
md_ri_to_chars(*where, &ri);
*where += md_reloc_size;
} /* if there is an add symbol */
} /* for each fix */
return;
} /* emit_relocations() */
/* Aout file generation & utilities */
void obj_header_append(where, headers)
char **where;
object_headers *headers;
{
tc_headers_hook(headers);
#ifdef CROSS_ASSEMBLE
md_number_to_chars(*where, headers->header.a_info, sizeof(headers->header.a_info));
*where += sizeof(headers->header.a_info);
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);
#ifdef EXEC_MACHINE_TYPE
md_number_to_chars(*where, headers->header.a_machtype, sizeof(headers->header.a_machtype));
*where += sizeof(headers->header.a_machtype);
#endif /* EXEC_MACHINE_TYPE */
#ifdef EXEC_VERSION
md_number_to_chars(*where, headers->header.a_version, sizeof(headers->header.a_version));
*where += sizeof(headers->header.a_version);
#endif /* EXEC_VERSION */
#else /* CROSS_ASSEMBLE */
append(where, (char *) &headers->header, sizeof(headers->header));
#endif /* CROSS_ASSEMBLE */
return;
} /* obj_append_header() */
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 *)&(S_GET_VALUE(symbolP)), S_GET_VALUE(symbolP), sizeof(S_GET_VALUE(symbolP)));
append(where, (char *)&symbolP->sy_symbol, sizeof(obj_symbol_type));
} /* obj_symbol_to_chars() */
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. */
register 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);
}
} /* emit_symbols() */
void obj_symbol_new_hook(symbolP)
symbolS *symbolP;
{
S_SET_OTHER(symbolP, 0);
S_SET_DESC(symbolP, 0);
return;
} /* obj_symbol_new_hook() */
static void obj_aout_line() {
/* 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();
} /* obj_aout_line() */
/*
* stab()
*
* Handle .stabX directives, which used to be open-coded.
* So much creeping featurism overloaded the semantics that we decided
* to put all .stabX thinking in one place. Here.
*
* We try to make any .stabX directive legal. Other people's AS will often
* do assembly-time consistency checks: eg assigning meaning to n_type bits
* and "protecting" you from setting them to certain values. (They also zero
* certain bits before emitting symbols. Tut tut.)
*
* If an expression is not absolute we either gripe or use the relocation
* information. Other people's assemblers silently forget information they
* don't need and invent information they need that you didn't supply.
*
* .stabX directives always make a symbol table entry. It may be junk if
* the rest of your .stabX directive is malformed.
*/
static void obj_aout_stab(what)
int what;
{
register symbolS * symbolP = 0;
register char * string;
int saved_type = 0;
int length;
int goof; /* TRUE if we have aborted. */
long longint;
/*
* Enter with input_line_pointer pointing past .stabX and any following
* whitespace.
*/
goof = 0; /* JF who forgot this?? */
if (what == 's') {
string = demand_copy_C_string(& length);
SKIP_WHITESPACE();
if (* input_line_pointer == ',')
input_line_pointer ++;
else {
as_bad("I need a comma after symbol's name");
goof = 1;
}
} else
string = "";
/*
* Input_line_pointer->after ','. String->symbol name.
*/
if (! goof) {
symbolP = symbol_new(string,
SEG_UNKNOWN,
0,
(struct frag *)0);
switch (what) {
case 'd':
S_SET_NAME(symbolP, NULL); /* .stabd feature. */
S_SET_VALUE(symbolP, obstack_next_free(&frags) - frag_now->fr_literal);
symbolP->sy_frag = frag_now;
break;
case 'n':
symbolP->sy_frag = &zero_address_frag;
break;
case 's':
symbolP->sy_frag = & zero_address_frag;
break;
default:
BAD_CASE(what);
break;
}
if (get_absolute_expression_and_terminator(&longint) == ',')
symbolP->sy_symbol.n_type = saved_type = longint;
else {
as_bad("I want a comma after the n_type expression");
goof = 1;
input_line_pointer --; /* Backup over a non-',' char. */
}
}
if (!goof) {
if (get_absolute_expression_and_terminator(&longint) == ',')
S_SET_OTHER(symbolP, longint);
else {
as_bad("I want a comma after the n_other expression");
goof = 1;
input_line_pointer--; /* Backup over a non-',' char. */
}
}
if (!goof) {
S_SET_DESC(symbolP, get_absolute_expression());
if (what == 's' || what == 'n') {
if (*input_line_pointer != ',') {
as_bad("I want a comma after the n_desc expression");
goof = 1;
} else {
input_line_pointer++;
}
}
}
if ((!goof) && (what=='s' || what=='n')) {
pseudo_set(symbolP);
symbolP->sy_symbol.n_type = saved_type;
}
if (goof)
ignore_rest_of_line();
else
demand_empty_rest_of_line ();
} /* obj_aout_stab() */
static void obj_aout_desc() {
register char *name;
register char c;
register char *p;
register symbolS *symbolP;
register int temp;
/*
* Frob invented at RMS' request. Set the n_desc of a symbol.
*/
name = input_line_pointer;
c = get_symbol_end();
p = input_line_pointer;
* p = c;
SKIP_WHITESPACE();
if (*input_line_pointer != ',') {
*p = 0;
as_bad("Expected comma after name \"%s\"", name);
*p = c;
ignore_rest_of_line();
} else {
input_line_pointer ++;
temp = get_absolute_expression();
*p = 0;
symbolP = symbol_find_or_make(name);
*p = c;
S_SET_DESC(symbolP,temp);
}
demand_empty_rest_of_line();
} /* obj_aout_desc() */
void obj_read_begin_hook() {
return;
} /* obj_read_begin_hook() */
void obj_crawl_symbol_chain(headers)
object_headers *headers;
{
symbolS *symbolP;
symbolS **symbolPP;
int symbol_number = 0;
/* JF deal with forward references first... */
for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) {
if (symbolP->sy_forward) {
S_SET_VALUE(symbolP, S_GET_VALUE(symbolP)
+ S_GET_VALUE(symbolP->sy_forward)
+ symbolP->sy_forward->sy_frag->fr_address);
symbolP->sy_forward=0;
} /* if it has a forward reference */
} /* walk the symbol chain */
tc_crawl_symbol_chain(headers);
symbolPP = &symbol_rootP; /*->last symbol chain link. */
while ((symbolP = *symbolPP) != NULL) {
if (flagseen['R'] && (S_GET_SEGMENT(symbolP) == SEG_DATA)) {
S_SET_SEGMENT(symbolP, SEG_TEXT);
} /* if pusing data into text */
S_SET_VALUE(symbolP, S_GET_VALUE(symbolP) + symbolP->sy_frag->fr_address);
/* 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 (!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' && (flagseen ['L'] || ! 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 = &(symbol_next(symbolP));
} 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);
return;
} /* obj_crawl_symbol_chain() */
/*
* Find strings by crawling along symbol table chain.
*/
void obj_emit_strings(where)
char **where;
{
symbolS *symbolP;
#ifdef CROSS_ASSEMBLE
/* 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_ASSEMBLE */
append (where, (char *)&string_byte_count, (unsigned long)sizeof(string_byte_count));
#endif /* CROSS_ASSEMBLE */
for(symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) {
if(S_GET_NAME(symbolP))
append(&next_object_file_charP, S_GET_NAME(symbolP),
(unsigned long)(strlen (S_GET_NAME(symbolP)) + 1));
} /* walk symbol chain */
return;
} /* obj_emit_strings() */
/*
* Local Variables:
* comment-column: 0
* fill-column: 131
* End:
*/
/* end of obj-aout.c */