gas/config/aout_gnu.h

   1 /* This file is aout_gnu.h
   2
   3    Copyright (C) 1987-1992 Free Software Foundation, Inc.
   4
   5    This file is part of GAS, the GNU Assembler.
   6
   7    GAS is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    GAS is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GAS; see the file COPYING.  If not, write to
  19    the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #ifndef __A_OUT_GNU_H__
  22 #define __A_OUT_GNU_H__
  23
  24 /* There are two main flavours of a.out, one which uses the standard
  25    relocations, and one which uses extended relocations.
  26
  27    Today, the extended reloc uses are
  28    TC_SPARC, TC_A29K
  29
  30    each must define the enum reloc_type
  31
  32 */
  33
  34 #define USE_EXTENDED_RELOC (defined(TC_SPARC) || defined(TC_A29K))
  35
  36 #if defined(TC_SPARC) || defined(TC_A29K)
  37 enum reloc_type {
  38         RELOC_8,        RELOC_16,        RELOC_32, /* simple relocations */
  39         RELOC_DISP8,    RELOC_DISP16,    RELOC_DISP32, /* pc-rel displacement */
  40         RELOC_WDISP30,  RELOC_WDISP22,
  41         RELOC_HI22,     RELOC_22,
  42         RELOC_13,       RELOC_LO10,
  43         RELOC_SFA_BASE, RELOC_SFA_OFF13,
  44         RELOC_BASE10,   RELOC_BASE13,    RELOC_BASE22, /* P.I.C. (base-relative) */
  45         RELOC_PC10,     RELOC_PC22,     /* for some sort of pc-rel P.I.C. (?) */
  46         RELOC_JMP_TBL,          /* P.I.C. jump table */
  47         RELOC_SEGOFF16,         /* reputedly for shared libraries somehow */
  48         RELOC_GLOB_DAT,  RELOC_JMP_SLOT, RELOC_RELATIVE,
  49         RELOC_11,
  50         RELOC_WDISP2_14,
  51         RELOC_WDISP19,
  52         RELOC_HHI22,
  53         RELOC_HLO10,
  54
  55         /* 29K relocation types */
  56         RELOC_JUMPTARG, RELOC_CONST,     RELOC_CONSTH,
  57
  58         RELOC_WDISP14, RELOC_WDISP21,
  59
  60         NO_RELOC,
  61 };
  62 #endif /* TC_SPARC or TC_A29K */
  63
  64
  65 #define __GNU_EXEC_MACROS__
  66
  67 #ifndef __STRUCT_EXEC_OVERRIDE__
  68
  69 /* This is the layout on disk of a Unix V7, Berkeley, SunOS, Vax Ultrix
  70    "struct exec".  Don't assume that on this machine, the "struct exec"
  71    will lay out the same sizes or alignments.  */
  72
  73 struct exec_bytes {
  74         unsigned char a_info[4];
  75         unsigned char a_text[4];
  76         unsigned char a_data[4];
  77         unsigned char a_bss[4];
  78         unsigned char a_syms[4];
  79         unsigned char a_entry[4];
  80         unsigned char a_trsize[4];
  81         unsigned char a_drsize[4];
  82 };
  83
  84 /* How big the "struct exec" is on disk */
  85 #define EXEC_BYTES_SIZE (8 * 4)
  86
  87 /* This is the layout in memory of a "struct exec" while we process it.  */
  88
  89 struct exec
  90 {
  91         unsigned long a_info;           /* Use macros N_MAGIC, etc for access */
  92         unsigned a_text;                /* length of text, in bytes */
  93         unsigned a_data;                /* length of data, in bytes */
  94         unsigned a_bss;         /* length of uninitialized data area for file, in bytes */
  95         unsigned a_syms;                /* length of symbol table data in file, in bytes */
  96         unsigned a_entry;               /* start address */
  97         unsigned a_trsize;              /* length of relocation info for text, in bytes */
  98         unsigned a_drsize;              /* length of relocation info for data, in bytes */
  99 };
 100
 101 #endif /* __STRUCT_EXEC_OVERRIDE__ */
 102
 103 /* these go in the N_MACHTYPE field */
 104 /* These symbols could be defined by code from Suns...punt 'em */
 105 #undef M_UNKNOWN
 106 #undef M_68010
 107 #undef M_68020
 108 #undef M_SPARC
 109 enum machine_type {
 110         M_UNKNOWN = 0,
 111         M_68010 = 1,
 112         M_68020 = 2,
 113         M_SPARC = 3,
 114         /* skip a bunch so we don't run into any of sun's numbers */
 115         M_386 = 100,
 116         M_29K = 101,
 117         M_RS6000 = 102, /* IBM RS/6000 */
 118         /* HP/BSD formats */
 119         M_HP200 = 200,  /* hp200 (68010) BSD binary */
 120         M_HP300 = 300,  /* hp300 (68020+68881) BSD binary */
 121         M_HPUX23 = 0x020C,      /* hp200/300 HPUX binary */
 122 };
 123
 124 #define N_MAGIC(exec) ((exec).a_info & 0xffff)
 125 #define N_MACHTYPE(exec) ((enum machine_type)(((exec).a_info >> 16) & 0xff))
 126 #define N_FLAGS(exec) (((exec).a_info >> 24) & 0xff)
 127 #define N_SET_INFO(exec, magic, type, flags) \
 128     ((exec).a_info = ((magic) & 0xffff) \
 129      | (((int)(type) & 0xff) << 16) \
 130      | (((flags) & 0xff) << 24))
 131 #define N_SET_MAGIC(exec, magic) \
 132     ((exec).a_info = (((exec).a_info & 0xffff0000) | ((magic) & 0xffff)))
 133
 134 #define N_SET_MACHTYPE(exec, machtype) \
 135     ((exec).a_info = \
 136      ((exec).a_info&0xff00ffff) | ((((int)(machtype))&0xff) << 16))
 137
 138 #define N_SET_FLAGS(exec, flags) \
 139     ((exec).a_info = \
 140      ((exec).a_info&0x00ffffff) | (((flags) & 0xff) << 24))
 141
 142 /* Code indicating object file or impure executable.  */
 143 #define OMAGIC 0407
 144 /* Code indicating pure executable.  */
 145 #define NMAGIC 0410
 146 /* Code indicating demand-paged executable.  */
 147 #define ZMAGIC 0413
 148
 149 /* Virtual Address of text segment from the a.out file.  For OMAGIC,
 150    (almost always "unlinked .o's" these days), should be zero.
 151    For linked files, should reflect reality if we know it.  */
 152
 153 #ifndef N_TXTADDR
 154 #define N_TXTADDR(x)    (N_MAGIC(x)==OMAGIC? 0 : TEXT_START_ADDR)
 155 #endif
 156
 157 #ifndef N_BADMAG
 158 #define N_BADMAG(x)       (N_MAGIC(x) != OMAGIC         \
 159                            && N_MAGIC(x) != NMAGIC              \
 160                            && N_MAGIC(x) != ZMAGIC)
 161 #endif
 162
 163 /* By default, segment size is constant.  But on some machines, it can
 164    be a function of the a.out header (e.g. machine type).  */
 165 #ifndef N_SEGSIZE
 166 #define N_SEGSIZE(x)    SEGMENT_SIZE
 167 #endif
 168
 169     /* This complexity is for encapsulated COFF support */
 170 #ifndef _N_HDROFF
 171 #define _N_HDROFF(x)    (N_SEGSIZE(x) - sizeof (struct exec))
 172 #endif
 173
 174 #ifndef N_TXTOFF
 175 #define N_TXTOFF(x)     (N_MAGIC(x) == ZMAGIC ? \
 176                          _N_HDROFF((x)) + sizeof (struct exec) :        \
 177                          sizeof (struct exec))
 178 #endif
 179
 180
 181 #ifndef N_DATOFF
 182 #define N_DATOFF(x)     ( N_TXTOFF(x) + (x).a_text )
 183 #endif
 184
 185 #ifndef N_TRELOFF
 186 #define N_TRELOFF(x)    ( N_DATOFF(x) + (x).a_data )
 187 #endif
 188
 189 #ifndef N_DRELOFF
 190 #define N_DRELOFF(x)    ( N_TRELOFF(x) + (x).a_trsize )
 191 #endif
 192
 193 #ifndef N_SYMOFF
 194 #define N_SYMOFF(x)     ( N_DRELOFF(x) + (x).a_drsize )
 195 #endif
 196
 197 #ifndef N_STROFF
 198 #define N_STROFF(x)     ( N_SYMOFF(x) + (x).a_syms )
 199 #endif
 200
 201 /* Address of text segment in memory after it is loaded.  */
 202 #ifndef N_TXTADDR
 203 #define N_TXTADDR(x)    0
 204 #endif
 205
 206 #ifndef N_DATADDR
 207 #define N_DATADDR(x) \
 208     (N_MAGIC(x)==OMAGIC? (N_TXTADDR(x)+(x).a_text) \
 209      :  (N_SEGSIZE(x) + ((N_TXTADDR(x)+(x).a_text-1) & ~(N_SEGSIZE(x)-1))))
 210 #endif
 211
 212 /* Address of bss segment in memory after it is loaded.  */
 213 #define N_BSSADDR(x) (N_DATADDR(x) + (x).a_data)
 214 \f
 215 struct nlist {
 216         union {
 217                 char *n_name;
 218                 struct nlist *n_next;
 219                 long n_strx;
 220         } n_un;
 221         unsigned char n_type;
 222         char n_other;
 223         short n_desc;
 224         unsigned long n_value;
 225 };
 226
 227 #define N_UNDF 0
 228 #define N_ABS 2
 229 #define N_TEXT 4
 230 #define N_DATA 6
 231 #define N_BSS 8
 232 #define N_COMM  0x12            /* common (visible in shared lib commons) */
 233 #define N_FN 0x1F               /* File name of a .o file */
 234
 235 /* Note: N_EXT can only usefully be OR-ed with N_UNDF, N_ABS, N_TEXT,
 236    N_DATA, or N_BSS.  When the low-order bit of other types is set,
 237    (e.g. N_WARNING versus N_FN), they are two different types.  */
 238 #define N_EXT 1
 239 #define N_TYPE 036
 240 #define N_STAB 0340
 241
 242 /* The following type indicates the definition of a symbol as being
 243    an indirect reference to another symbol.  The other symbol
 244    appears as an undefined reference, immediately following this symbol.
 245
 246    Indirection is asymmetrical.  The other symbol's value will be used
 247    to satisfy requests for the indirect symbol, but not vice versa.
 248    If the other symbol does not have a definition, libraries will
 249    be searched to find a definition.  */
 250
 251 #define N_INDR 0xa
 252
 253 /* The following symbols refer to set elements.
 254    All the N_SET[ATDB] symbols with the same name form one set.
 255    Space is allocated for the set in the text section, and each set
 256    element's value is stored into one word of the space.
 257    The first word of the space is the length of the set (number of elements).
 258
 259    The address of the set is made into an N_SETV symbol
 260    whose name is the same as the name of the set.
 261    This symbol acts like a N_DATA global symbol
 262    in that it can satisfy undefined external references.  */
 263
 264 /* These appear as input to LD, in a .o file.  */
 265 #define N_SETA  0x14            /* Absolute set element symbol */
 266 #define N_SETT  0x16            /* Text set element symbol */
 267 #define N_SETD  0x18            /* Data set element symbol */
 268 #define N_SETB  0x1A            /* Bss set element symbol */
 269
 270 /* This is output from LD.  */
 271 #define N_SETV  0x1C            /* Pointer to set vector in data area.  */
 272
 273 /* Warning symbol. The text gives a warning message, the next symbol
 274    in the table will be undefined. When the symbol is referenced, the
 275    message is printed.  */
 276
 277 #define N_WARNING 0x1e
 278 \f
 279 /* This structure describes a single relocation to be performed.
 280    The text-relocation section of the file is a vector of these structures,
 281    all of which apply to the text section.
 282    Likewise, the data-relocation section applies to the data section.  */
 283
 284 /* The following enum and struct were borrowed from SunOS's
 285    /usr/include/sun4/a.out.h  and extended to handle
 286    other machines.  It is currently used on SPARC and AMD 29000.
 287
 288    reloc_ext_bytes is how it looks on disk.  reloc_info_extended is
 289    how we might process it on a native host.  */
 290 #if USE_EXTENDED_RELOC
 291
 292 struct reloc_ext_bytes {
 293         unsigned char   r_address[4];
 294         unsigned char r_index[3];
 295         unsigned char r_bits[1];
 296         unsigned char r_addend[4];
 297 };
 298
 299
 300 #define RELOC_EXT_BITS_EXTERN_BIG       0x80
 301 #define RELOC_EXT_BITS_EXTERN_LITTLE    0x01
 302
 303 #define RELOC_EXT_BITS_TYPE_BIG         0x1F
 304 #define RELOC_EXT_BITS_TYPE_SH_BIG      0
 305 #define RELOC_EXT_BITS_TYPE_LITTLE      0xF8
 306 #define RELOC_EXT_BITS_TYPE_SH_LITTLE   3
 307
 308 #define RELOC_EXT_SIZE  12              /* Bytes per relocation entry */
 309
 310 struct reloc_info_extended
 311 {
 312         unsigned long r_address;
 313         unsigned int  r_index:24;
 314 # define        r_symbolnum  r_index
 315         unsigned        r_extern:1;
 316         unsigned        :2;
 317         /*  RS/6000 compiler does not support enum bitfield
 318             enum reloc_type r_type:5; */
 319         enum reloc_type r_type;
 320         long int        r_addend;
 321 };
 322
 323 #else
 324
 325 /* The standard, old-fashioned, Berkeley compatible relocation struct */
 326
 327
 328
 329 #ifdef TC_I860
 330 /* NOTE: three bits max, see struct reloc_info_i860.r_type */
 331 enum i860_reloc_type {
 332         NO_RELOC = 0, BRADDR, LOW0, LOW1, LOW2, LOW3, LOW4, SPLIT0, SPLIT1, SPLIT2, RELOC_32,
 333 };
 334
 335 typedef enum i860_reloc_type reloc_type;
 336
 337  /* NOTE: two bits max, see reloc_info_i860.r_type */
 338 enum highlow_type {
 339         NO_SPEC = 0, PAIR, HIGH, HIGHADJ,
 340 };
 341
 342
 343 struct reloc_info_i860
 344 {
 345         unsigned long r_address;
 346         /*
 347          * Using bit fields here is a bad idea because the order is not portable. :-(
 348          */
 349         unsigned int r_symbolnum: 24;
 350         unsigned int r_pcrel    : 1;
 351         unsigned int r_extern   : 1;
 352         /* combining the two field simplifies the argument passing in "new_fix()" */
 353         /* and is compatible with the existing Sparc #ifdef's */
 354         /* r_type:  highlow_type - bits 5,4; reloc_type - bits 3-0 */
 355         unsigned int r_type     : 6;
 356         long r_addend;
 357 };
 358
 359 #endif /* TC_I860 */
 360
 361
 362 struct reloc_std_bytes {
 363         unsigned char   r_address[4];
 364         unsigned char r_index[3];
 365         unsigned char r_bits[1];
 366 };
 367
 368 #define RELOC_STD_BITS_PCREL_BIG        0x80
 369 #define RELOC_STD_BITS_PCREL_LITTLE     0x01
 370
 371 #define RELOC_STD_BITS_LENGTH_BIG       0x60
 372 #define RELOC_STD_BITS_LENGTH_SH_BIG    5       /* To shift to units place */
 373 #define RELOC_STD_BITS_LENGTH_LITTLE    0x06
 374 #define RELOC_STD_BITS_LENGTH_SH_LITTLE 1
 375
 376 #define RELOC_STD_BITS_EXTERN_BIG       0x10
 377 #define RELOC_STD_BITS_EXTERN_LITTLE    0x08
 378
 379 #define RELOC_STD_BITS_BASEREL_BIG      0x08
 380 #define RELOC_STD_BITS_BASEREL_LITTLE   0x08
 381
 382 #define RELOC_STD_BITS_JMPTABLE_BIG     0x04
 383 #define RELOC_STD_BITS_JMPTABLE_LITTLE  0x04
 384
 385 #define RELOC_STD_BITS_RELATIVE_BIG     0x02
 386 #define RELOC_STD_BITS_RELATIVE_LITTLE  0x02
 387
 388 #define RELOC_STD_SIZE  8               /* Bytes per relocation entry */
 389
 390 #endif /* USE_EXTENDED_RELOC */
 391
 392 #ifndef CUSTOM_RELOC_FORMAT
 393 struct relocation_info
 394 {
 395         /* Address (within segment) to be relocated.  */
 396         int r_address;
 397         /* The meaning of r_symbolnum depends on r_extern.  */
 398         unsigned int r_symbolnum:24;
 399         /* Nonzero means value is a pc-relative offset
 400            and it should be relocated for changes in its own address
 401            as well as for changes in the symbol or section specified.  */
 402         unsigned int r_pcrel:1;
 403         /* Length (as exponent of 2) of the field to be relocated.
 404            Thus, a value of 2 indicates 1<<2 bytes.  */
 405         unsigned int r_length:2;
 406         /* 1 => relocate with value of symbol.
 407            r_symbolnum is the index of the symbol
 408            in file's the symbol table.
 409            0 => relocate with the address of a segment.
 410            r_symbolnum is N_TEXT, N_DATA, N_BSS or N_ABS
 411            (the N_EXT bit may be set also, but signifies nothing).  */
 412         unsigned int r_extern:1;
 413         /* The next three bits are for SunOS shared libraries, and seem to
 414            be undocumented.  */
 415         unsigned int r_baserel:1;       /* Linkage table relative */
 416         unsigned int r_jmptable:1;      /* pc-relative to jump table */
 417
 418 #ifdef TC_NS32K
 419 #define r_bsr   r_baserel
 420 #define r_disp  r_jmptable
 421 #endif /* TC_NS32K */
 422
 423         unsigned int r_relative:1;      /* "relative relocation" */
 424         /* unused */
 425         unsigned int r_pad:1;           /* Padding -- set to zero */
 426 };
 427 #endif /* CUSTOM_RELOC_FORMAT */
 428
 429 #endif /* __A_OUT_GNU_H__ */
 430
 431 /* end of aout_gnu.h */