NetBSD/gnu/usr.bin/gas/config/obj-bout.h

314 lines
11 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. */
/*
* This file is a modified version of 'a.out.h'. It is to be used in all GNU
* tools modified to support the i80960 b.out format (or tools that operate on
* object files created by such tools).
*
* All i80960 development is done in a CROSS-DEVELOPMENT environment. I.e.,
* object code is generated on, and executed under the direction of a symbolic
* debugger running on, a host system. We do not want to be subject to the
* vagaries of which host it is or whether it supports COFF or a.out format, or
* anything else. We DO want to:
*
* o always generate the same format object files, regardless of host.
*
* o have an 'a.out' header that we can modify for our own purposes
* (the 80960 is typically an embedded processor and may require
* enhanced linker support that the normal a.out.h header can't
* accommodate).
*
* As for byte-ordering, the following rules apply:
*
* o Text and data that is actually downloaded to the target is always
* in i80960 (little-endian) order.
*
* o All other numbers (in the header, symbols, relocation directives)
* are in host byte-order: object files CANNOT be lifted from a
* little-end host and used on a big-endian (or vice versa) without
* modification.
*
* o The downloader ('comm960') takes care to generate a pseudo-header
* with correct (i80960) byte-ordering before shipping text and data
* off to the NINDY monitor in the target systems. Symbols and
* relocation info are never sent to the target.
*/
#define OBJ_BOUT 1
#include "targ-cpu.h"
/* bout uses host byte order for headers */
#ifdef CROSS_COMPILE
#undef CROSS_COMPILE
#endif /* CROSS_COMPILE */
/* We want \v. */
#define BACKSLASH_V 1
#define OBJ_DEFAULT_OUTPUT_FILE_NAME "b.out"
extern const short seg_N_TYPE[];
extern const segT N_TYPE_seg[];
#define BMAGIC 0415
/* We don't accept the following (see N_BADMAG macro).
* They're just here so GNU code will compile.
*/
#define OMAGIC 0407 /* old impure format */
#define NMAGIC 0410 /* read-only text */
#define ZMAGIC 0413 /* demand load format */
/* FILE HEADER
* All 'lengths' are given as a number of bytes.
* All 'alignments' are for relinkable files only; an alignment of
* 'n' indicates the corresponding segment must begin at an
* address that is a multiple of (2**n).
*/
struct exec {
/* Standard stuff */
unsigned long a_magic; /* Identifies this as a b.out file */
unsigned long a_text; /* Length of text */
unsigned long a_data; /* Length of data */
unsigned long a_bss; /* Length of runtime uninitialized data area */
unsigned long a_syms; /* Length of symbol table */
unsigned long a_entry; /* Runtime start address */
unsigned long a_trsize; /* Length of text relocation info */
unsigned long a_drsize; /* Length of data relocation info */
/* Added for i960 */
unsigned long a_tload; /* Text runtime load address */
unsigned long a_dload; /* Data runtime load address */
unsigned char a_talign; /* Alignment of text segment */
unsigned char a_dalign; /* Alignment of data segment */
unsigned char a_balign; /* Alignment of bss segment */
unsigned char unused; /* (Just to make struct size a multiple of 4) */
};
#define N_BADMAG(x) (((x).a_magic) != BMAGIC)
#define N_TXTOFF(x) ( sizeof(struct exec) )
#define N_DATOFF(x) ( N_TXTOFF(x) + (x).a_text )
#define N_TROFF(x) ( N_DATOFF(x) + (x).a_data )
#define N_DROFF(x) ( N_TROFF(x) + (x).a_trsize )
#define N_SYMOFF(x) ( N_DROFF(x) + (x).a_drsize )
#define N_STROFF(x) ( N_SYMOFF(x) + (x).a_syms )
/* A single entry in the symbol table
*/
struct nlist {
union {
char *n_name;
struct nlist *n_next;
long n_strx; /* Index into string table */
} n_un;
unsigned char n_type; /* See below */
char n_other; /* Used in i80960 support -- see below */
short n_desc;
unsigned long n_value;
};
typedef struct nlist obj_symbol_type;
/* Legal values of n_type
*/
#define N_UNDF 0 /* Undefined symbol */
#define N_ABS 2 /* Absolute symbol */
#define N_TEXT 4 /* Text symbol */
#define N_DATA 6 /* Data symbol */
#define N_BSS 8 /* BSS symbol */
#define N_FN 31 /* Filename symbol */
#define N_EXT 1 /* External symbol (OR'd in with one of above) */
#define N_TYPE 036 /* Mask for all the type bits */
#define N_STAB 0340 /* Mask for all bits used for SDB entries */
#ifndef CUSTOM_RELOC_FORMAT
struct relocation_info {
int r_address; /* File address of item to be relocated */
unsigned
r_index:24,/* Index of symbol on which relocation is based*/
r_pcrel:1, /* 1 => relocate PC-relative; else absolute
* On i960, pc-relative implies 24-bit
* address, absolute implies 32-bit.
*/
r_length:2, /* Number of bytes to relocate:
* 0 => 1 byte
* 1 => 2 bytes
* 2 => 4 bytes -- only value used for i960
*/
r_extern:1,
r_bsr:1, /* Something for the GNU NS32K assembler */
r_disp:1, /* Something for the GNU NS32K assembler */
r_callj:1, /* 1 if relocation target is an i960 'callj' */
nuthin:1; /* Unused */
};
#endif /* CUSTOM_RELOC_FORMAT */
/*
* Macros to extract information from a symbol table entry.
* This syntaxic indirection allows independence regarding a.out or coff.
* The argument (s) of all these macros is a pointer to a symbol table entry.
*/
/* Predicates */
/* True if the symbol is external */
#define S_IS_EXTERNAL(s) ((s)->sy_symbol.n_type & N_EXT)
/* True if symbol has been defined, ie is in N_{TEXT,DATA,BSS,ABS} or N_EXT */
#define S_IS_DEFINED(s) ((S_GET_TYPE(s) != N_UNDF) || (S_GET_DESC(s) != 0))
#define S_IS_REGISTER(s) ((s)->sy_symbol.n_type == N_REGISTER)
/* True if a debug special symbol entry */
#define S_IS_DEBUG(s) ((s)->sy_symbol.n_type & N_STAB)
/* True if a symbol is local symbol name */
/* A symbol name whose name begin with ^A is a gas internal pseudo symbol
nameless symbols come from .stab directives. */
#define S_IS_LOCAL(s) (S_GET_NAME(s) && \
!S_IS_DEBUG(s) && \
(S_GET_NAME(s)[0] == '\001' || \
(S_LOCAL_NAME(s) && !flagseen['L'])))
/* True if a symbol is not defined in this file */
#define S_IS_EXTERN(s) ((s)->sy_symbol.n_type & N_EXT)
/* True if the symbol has been generated because of a .stabd directive */
#define S_IS_STABD(s) (S_GET_NAME(s) == NULL)
/* Accessors */
/* The value of the symbol */
#define S_GET_VALUE(s) ((unsigned long) ((s)->sy_symbol.n_value))
/* The name of the symbol */
#define S_GET_NAME(s) ((s)->sy_symbol.n_un.n_name)
/* The pointer to the string table */
#define S_GET_OFFSET(s) ((s)->sy_symbol.n_un.n_strx)
/* The type of the symbol */
#define S_GET_TYPE(s) ((s)->sy_symbol.n_type & N_TYPE)
/* The numeric value of the segment */
#define S_GET_SEGMENT(s) (N_TYPE_seg[S_GET_TYPE(s)])
/* The n_other expression value */
#define S_GET_OTHER(s) ((s)->sy_symbol.n_other)
/* The n_desc expression value */
#define S_GET_DESC(s) ((s)->sy_symbol.n_desc)
/* Modifiers */
/* Set the value of the symbol */
#define S_SET_VALUE(s,v) ((s)->sy_symbol.n_value = (unsigned long) (v))
/* Assume that a symbol cannot be simultaneously in more than on segment */
/* set segment */
#define S_SET_SEGMENT(s,seg) ((s)->sy_symbol.n_type &= ~N_TYPE,(s)->sy_symbol.n_type|=SEGMENT_TO_SYMBOL_TYPE(seg))
/* The symbol is external */
#define S_SET_EXTERNAL(s) ((s)->sy_symbol.n_type |= N_EXT)
/* The symbol is not external */
#define S_CLEAR_EXTERNAL(s) ((s)->sy_symbol.n_type &= ~N_EXT)
/* Set the name of the symbol */
#define S_SET_NAME(s,v) ((s)->sy_symbol.n_un.n_name = (v))
/* Set the offset in the string table */
#define S_SET_OFFSET(s,v) ((s)->sy_symbol.n_un.n_strx = (v))
/* Set the n_other expression value */
#define S_SET_OTHER(s,v) ((s)->sy_symbol.n_other = (v))
/* Set the n_desc expression value */
#define S_SET_DESC(s,v) ((s)->sy_symbol.n_desc = (v))
/* File header macro and type definition */
#define H_GET_FILE_SIZE(h) (sizeof(struct exec) + \
H_GET_TEXT_SIZE(h) + H_GET_DATA_SIZE(h) + \
H_GET_SYMBOL_TABLE_SIZE(h) + \
H_GET_TEXT_RELOCATION_SIZE(h) + \
H_GET_DATA_RELOCATION_SIZE(h) + \
(h)->string_table_size)
#define H_GET_HEADER_SIZE(h) (sizeof(struct exec))
#define H_GET_TEXT_SIZE(h) ((h)->header.a_text)
#define H_GET_DATA_SIZE(h) ((h)->header.a_data)
#define H_GET_BSS_SIZE(h) ((h)->header.a_bss)
#define H_GET_TEXT_RELOCATION_SIZE(h) ((h)->header.a_trsize)
#define H_GET_DATA_RELOCATION_SIZE(h) ((h)->header.a_drsize)
#define H_GET_SYMBOL_TABLE_SIZE(h) ((h)->header.a_syms)
#define H_GET_MAGIC_NUMBER(h) ((h)->header.a_info)
#define H_GET_ENTRY_POINT(h) ((h)->header.a_entry)
#define H_GET_STRING_SIZE(h) ((h)->string_table_size)
#define H_GET_LINENO_SIZE(h) (0)
#ifdef EXEC_MACHINE_TYPE
#define H_GET_MACHINE_TYPE(h) ((h)->header.a_machtype)
#endif /* EXEC_MACHINE_TYPE */
#ifdef EXEC_VERSION
#define H_GET_VERSION(h) ((h)->header.a_version)
#endif /* EXEC_VERSION */
#define H_SET_TEXT_SIZE(h,v) ((h)->header.a_text = (v))
#define H_SET_DATA_SIZE(h,v) ((h)->header.a_data = (v))
#define H_SET_BSS_SIZE(h,v) ((h)->header.a_bss = (v))
#define H_SET_RELOCATION_SIZE(h,t,d) (H_SET_TEXT_RELOCATION_SIZE((h),(t)),\
H_SET_DATA_RELOCATION_SIZE((h),(d)))
#define H_SET_TEXT_RELOCATION_SIZE(h,v) ((h)->header.a_trsize = (v))
#define H_SET_DATA_RELOCATION_SIZE(h,v) ((h)->header.a_drsize = (v))
#define H_SET_SYMBOL_TABLE_SIZE(h,v) ((h)->header.a_syms = (v) * \
sizeof(struct nlist))
#define H_SET_MAGIC_NUMBER(h,v) ((h)->header.a_magic = (v))
#define H_SET_ENTRY_POINT(h,v) ((h)->header.a_entry = (v))
#define H_SET_STRING_SIZE(h,v) ((h)->string_table_size = (v))
#ifdef EXEC_MACHINE_TYPE
#define H_SET_MACHINE_TYPE(h,v) ((h)->header.a_machtype = (v))
#endif /* EXEC_MACHINE_TYPE */
#ifdef EXEC_VERSION
#define H_SET_VERSION(h,v) ((h)->header.a_version = (v))
#endif /* EXEC_VERSION */
/*
* Current means for getting the name of a segment.
* This will change for infinite-segments support (e.g. COFF).
*/
#define segment_name(seg) ( seg_name[(int)(seg)] )
extern char *const seg_name[];
typedef struct {
struct exec header; /* a.out header */
long string_table_size; /* names + '\0' + sizeof(int) */
} object_headers;
/* unused hooks. */
#define OBJ_EMIT_LINENO(a, b, c) {;}
#if __STDC__
struct fix;
void tc_aout_fix_to_chars(char *where, struct fix *fixP, relax_addressT segment_address);
#else /* not __STDC__ */
void tc_aout_fix_to_chars();
#endif /* not __STDC__ */
enum reloc_type {
NO_RELOC, RELOC_32,
};
/*
* Local Variables:
* comment-column: 0
* fill-column: 131
* End:
*/
/* end of obj-bout.h */