freebsd-nq/gnu/usr.bin/as/config/obj-bout.c
1995-05-30 05:05:38 +00:00

477 lines
13 KiB
C

/* b.out object file format
Copyright (C) 1989, 1990, 1991, 1992 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "as.h"
#include "obstack.h"
#ifndef NO_LISTING
#include "aout/stab_gnu.h"
#endif /* NO_LISTING */
const short /* in: segT out: N_TYPE bits */
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_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,
};
#if __STDC__ == 1
static void obj_bout_stab(int what);
static void obj_bout_line(void);
static void obj_bout_desc(void);
#else /* not __STDC__ */
static void obj_bout_desc();
static void obj_bout_stab();
static void obj_bout_line();
#endif /* not __STDC__ */
const pseudo_typeS obj_pseudo_table[] = {
/* stabs (aka a.out aka b.out directives for debug symbols) */
{ "desc", obj_bout_desc, 0 }, /* def */
{ "line", obj_bout_line, 0 }, /* source code line number */
{ "stabd", obj_bout_stab, 'd' }, /* stabs */
{ "stabn", obj_bout_stab, 'n' }, /* stabs */
{ "stabs", obj_bout_stab, 's' }, /* stabs */
/* 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 */
}; /* obj_pseudo_table */
/* Relocation. */
/*
* 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;
{
for (; fixP; fixP = fixP->fx_next) {
if (fixP->fx_addsy != NULL) {
tc_bout_fix_to_chars(*where, fixP, segment_address_in_file);
*where += sizeof(struct relocation_info);
} /* if there's a symbol */
} /* for each fixup */
} /* emit_relocations() */
/* 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];
if (headers->header.a_talign < 2){
headers->header.a_talign = 2;
} /* force to at least 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));
append(where, (char *) &headers->header, sizeof(headers->header));
} /* a_header_append() */
void obj_symbol_to_chars(where, symbolP)
char **where;
symbolS *symbolP;
{
/* leave in host byte order */
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. */
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_bout_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_bout_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_bout_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;
}
#ifndef NO_LISTING
{
extern int listing;
if (listing && !goof) {
if (symbolP->sy_symbol.n_type == N_SLINE) {
listing_source_line(symbolP->sy_symbol.n_desc);
} else if (symbolP->sy_symbol.n_type == N_SO
|| symbolP->sy_symbol.n_type == N_SOL) {
listing_source_file(string);
}
}
}
#endif
if (goof)
ignore_rest_of_line ();
else
demand_empty_rest_of_line ();
} /* obj_bout_stab() */
static void obj_bout_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_bout_desc() */
void obj_read_begin_hook() {
return;
} /* obj_read_begin_hook() */
void obj_crawl_symbol_chain(headers)
object_headers *headers;
{
symbolS **symbolPP;
symbolS *symbolP;
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 (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' && (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_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 */
return;
} /* obj_emit_strings() */
void obj_pre_write_hook(headers)
object_headers *headers;
{
H_SET_MAGIC_NUMBER(headers, BMAGIC);
H_SET_ENTRY_POINT(headers, 0);
return;
} /* obj_pre_write_hook() */
/*
* Local Variables:
* comment-column: 0
* fill-column: 131
* End:
*/
/* end of obj-bout.c */