source: trunk/libs/newlib/src/include/coff/xcoff.h @ 581

Last change on this file since 581 was 444, checked in by satin@…, 6 years ago

add newlib,libalmos-mkh, restructure shared_syscalls.h and mini-libc

File size: 19.3 KB
Line 
1/* Internal format of XCOFF object file data structures for BFD.
2
3   Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2005,
4   2009, 2010  Free Software Foundation, Inc.
5   Written by Ian Lance Taylor <ian@cygnus.com>, Cygnus Support.
6
7   This file is part of BFD, the Binary File Descriptor library.
8
9   This program is free software; you can redistribute it and/or modify
10   it under the terms of the GNU General Public License as published by
11   the Free Software Foundation; either version 3 of the License, or
12   (at your option) any later version.
13   
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18   
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22   MA 02110-1301, USA.  */
23
24#ifndef _INTERNAL_XCOFF_H
25#define _INTERNAL_XCOFF_H
26
27/* XCOFF specific f_flags.  */
28
29/* File was profiled with fdpr.  */
30#define F_FDPR_PROF 0x0010
31
32/* File was reordered with fdpr.  */
33#define F_FDPR_OPTI 0x0020
34
35/* File use very large program support.  */
36#define F_DSA       0x0040
37
38/* One aux header specifying medium page sizes is non-zero.  */
39#define F_VARPG     0x0100
40
41/* Read/write sections are non-executable.  */
42#define F_NONEXEC   0x8000
43
44/* Linker */
45
46/* Names of "special" sections.  */
47#define _TEXT   ".text"
48#define _DATA   ".data"
49#define _BSS    ".bss"
50#define _PAD    ".pad"
51#define _LOADER ".loader"
52#define _EXCEPT ".except"
53#define _TYPCHK ".typchk"
54
55/* XCOFF uses special .dwXXX sections with the type STYP_DWARF.  */
56#define STYP_DWARF  0x0010
57
58/* High-order 16-bits dwarf subtypes.  */
59#define SSUBTYP_DWINFO  0x10000
60#define SSUBTYP_DWLINE  0x20000
61#define SSUBTYP_DWPBNMS 0x30000
62#define SSUBTYP_DWPBTYP 0x40000
63#define SSUBTYP_DWARNGE 0x50000
64#define SSUBTYP_DWABREV 0x60000
65#define SSUBTYP_DWSTR   0x70000
66#define SSUBTYP_DWRNGES 0x80000
67
68/* XCOFF uses a special .loader section with type STYP_LOADER.  */
69#define STYP_LOADER 0x1000
70
71/* Specifies an exception section.  A section of this type provides
72   information to identify the reason that a trap or ececptin occured within
73   and executable object program */
74#define STYP_EXCEPT 0x0100
75
76/* Specifies an initialized thread-local data section.  */
77#define STYP_TDATA  0x0400
78
79/* Specifies an uninitialized thread-local data section.  */
80#define STYP_TBSS   0x0800
81
82/* XCOFF uses a special .debug section with type STYP_DEBUG.  */
83#define STYP_DEBUG  0x2000
84
85/* Specifies a type check section.  A section of this type contains parameter
86   argument type check strings used by the AIX binder.  */
87#define STYP_TYPCHK 0x4000
88
89/* XCOFF handles line number or relocation overflow by creating
90   another section header with STYP_OVRFLO set.  */
91#define STYP_OVRFLO 0x8000
92
93#define RS6K_AOUTHDR_OMAGIC 0x0107 /* old: text & data writeable */
94#define RS6K_AOUTHDR_NMAGIC 0x0108 /* new: text r/o, data r/w */
95#define RS6K_AOUTHDR_ZMAGIC 0x010B /* paged: text r/o, both page-aligned */
96
97/* XCOFF relocation types. 
98   The relocations are described in the function 
99   xcoff[64]_ppc_relocate_section in coff64-rs6000.c and coff-rs6000.c  */
100
101#define R_POS   (0x00)
102#define R_NEG   (0x01)
103#define R_REL   (0x02)
104#define R_TOC   (0x03)
105#define R_RTB   (0x04)
106#define R_GL    (0x05)
107#define R_TCL   (0x06)
108#define R_BA    (0x08)
109#define R_BR    (0x0a)
110#define R_RL    (0x0c)
111#define R_RLA   (0x0d)
112#define R_REF   (0x0f)
113#define R_TRL   (0x12)
114#define R_TRLA  (0x13)
115#define R_RRTBI (0x14)
116#define R_RRTBA (0x15)
117#define R_CAI   (0x16)
118#define R_CREL  (0x17)
119#define R_RBA   (0x18)
120#define R_RBAC  (0x19)
121#define R_RBR   (0x1a)
122#define R_RBRC  (0x1b)
123#define R_TLS   (0x20)
124#define R_TLS_IE (0x21)
125#define R_TLS_LD (0x22)
126#define R_TLS_LE (0x23)
127#define R_TLSM  (0x24)
128#define R_TLSML (0x25)
129#define R_TOCU  (0x30)
130#define R_TOCL  (0x31)
131
132/* Storage class #defines, from /usr/include/storclass.h that are not already
133   defined in internal.h */
134
135/* Comment string in .info section */
136#define C_INFO          110     
137
138/* Dwarf symbol.  */
139#define C_DWARF         112
140
141/* Auxillary Symbol Entries  */
142
143/* x_smtyp values:  */
144#define SMTYP_ALIGN(x)  ((x) >> 3)      /* log2 of alignment */
145#define SMTYP_SMTYP(x)  ((x) & 0x7)     /* symbol type */
146/* Symbol type values:  */
147#define XTY_ER  0               /* External reference */
148#define XTY_SD  1               /* Csect definition */
149#define XTY_LD  2               /* Label definition */
150#define XTY_CM  3               /* .BSS */
151#define XTY_EM  4               /* Error message */
152#define XTY_US  5               /* "Reserved for internal use" */
153
154/* x_smclas values:  */
155#define XMC_PR  0               /* Read-only program code */
156#define XMC_RO  1               /* Read-only constant */
157#define XMC_DB  2               /* Read-only debug dictionary table */
158#define XMC_TC  3               /* Read-write general TOC entry */
159#define XMC_UA  4               /* Read-write unclassified */
160#define XMC_RW  5               /* Read-write data */
161#define XMC_GL  6               /* Read-only global linkage */
162#define XMC_XO  7               /* Read-only extended operation */
163#define XMC_SV  8               /* Read-only supervisor call */
164#define XMC_BS  9               /* Read-write BSS */
165#define XMC_DS  10              /* Read-write descriptor csect */
166#define XMC_UC  11              /* Read-write unnamed Fortran common */
167#define XMC_TI  12              /* Read-only traceback index csect */
168#define XMC_TB  13              /* Read-only traceback table csect */
169/*              14      ??? */
170#define XMC_TC0 15              /* Read-write TOC anchor */
171#define XMC_TD  16              /* Read-write data in TOC */
172#define XMC_SV64   17           /* Read-only 64 bit supervisor call */
173#define XMC_SV3264 18           /* Read-only 32 or 64 bit supervisor call */
174/*                19   ??? */
175#define XMC_TL     20          /* Read-write initialized TLS data */
176#define XMC_TU     21          /* Read-write uninitialized TLS data */
177#define XMC_TE     22          /* Same as XMC_TC but mapped after it */
178
179/* The ldhdr structure.  This appears at the start of the .loader
180   section.  */
181
182struct internal_ldhdr
183{
184  /* The version number:
185     1 : 32 bit
186     2 : 64 bit */
187  unsigned long l_version;
188
189  /* The number of symbol table entries.  */
190  bfd_size_type l_nsyms;
191
192  /* The number of relocation table entries.  */
193  bfd_size_type l_nreloc;
194
195  /* The length of the import file string table.  */
196  bfd_size_type l_istlen;
197
198  /* The number of import files.  */
199  bfd_size_type l_nimpid;
200
201  /* The offset from the start of the .loader section to the first
202     entry in the import file table.  */
203  bfd_size_type l_impoff;
204
205  /* The length of the string table.  */
206  bfd_size_type l_stlen;
207
208  /* The offset from the start of the .loader section to the first
209     entry in the string table.  */
210  bfd_size_type l_stoff;
211
212  /* The offset to start of the symbol table, only in XCOFF64 */
213  bfd_vma l_symoff;
214
215  /* The offset to the start of the relocation table, only in XCOFF64 */
216  bfd_vma l_rldoff;
217};
218
219/* The ldsym structure.  This is used to represent a symbol in the
220   .loader section.  */
221
222struct internal_ldsym
223{
224  union
225  {
226    /* The symbol name if <= SYMNMLEN characters.  */
227    char _l_name[SYMNMLEN];
228    struct
229    {
230      /* Zero if the symbol name is more than SYMNMLEN characters.  */
231        long _l_zeroes;
232     
233      /* The offset in the string table if the symbol name is more
234         than SYMNMLEN characters.  */
235      long _l_offset;
236    } 
237    _l_l;
238  }
239  _l;
240
241  /* The symbol value.  */
242  bfd_vma l_value;
243
244  /* The symbol section number.  */
245  short l_scnum;
246
247  /* The symbol type and flags.  */
248  char l_smtype;
249
250  /* The symbol storage class.  */
251  char l_smclas;
252
253  /* The import file ID.  */
254  bfd_size_type l_ifile;
255
256  /* Offset to the parameter type check string.  */
257  bfd_size_type l_parm;
258};
259
260/* These flags are for the l_smtype field (the lower three bits are an
261   XTY_* value).  */
262
263/* Imported symbol.  */
264#define L_IMPORT (0x40)
265/* Entry point.  */
266#define L_ENTRY (0x20)
267/* Exported symbol.  */
268#define L_EXPORT (0x10)
269/* Weak symbol.  */
270#define L_WEAK (0x08)
271
272/* The ldrel structure.  This is used to represent a reloc in the
273   .loader section.  */
274
275struct internal_ldrel
276{
277  /* The reloc address.  */
278  bfd_vma l_vaddr;
279
280  /* The symbol table index in the .loader section symbol table.  */
281  bfd_size_type l_symndx;
282
283  /* The relocation type and size.  */
284  short l_rtype;
285
286  /* The section number this relocation applies to.  */
287  short l_rsecnm;
288};
289
290/* An entry in the XCOFF linker hash table.  */
291struct xcoff_link_hash_entry
292{
293  struct bfd_link_hash_entry root;
294
295  /* Symbol index in output file.  Set to -1 initially.  Set to -2 if
296     there is a reloc against this symbol.  */
297  long indx;
298
299  /* If we have created a TOC entry for this symbol, this is the .tc
300     section which holds it.  */
301  asection *toc_section;
302
303  union
304  {
305    /* If we have created a TOC entry (the XCOFF_SET_TOC flag is
306       set), this is the offset in toc_section.  */
307    bfd_vma toc_offset;
308   
309    /* If the TOC entry comes from an input file, this is set to the
310       symbol index of the C_HIDEXT XMC_TC or XMC_TD symbol.  */
311    long toc_indx;
312  } 
313  u;
314
315  /* If this symbol is a function entry point which is called, this
316     field holds a pointer to the function descriptor.  If this symbol
317     is a function descriptor, this field holds a pointer to the
318     function entry point.  */
319  struct xcoff_link_hash_entry *descriptor;
320
321  /* The .loader symbol table entry, if there is one.  */
322  struct internal_ldsym *ldsym;
323
324  /* If XCOFF_BUILT_LDSYM is set, this is the .loader symbol table
325     index.  If XCOFF_BUILD_LDSYM is clear, and XCOFF_IMPORT is set,
326     this is the l_ifile value.  */
327  long ldindx;
328
329  /* Some linker flags.  */
330  unsigned long flags;
331
332  /* The storage mapping class.  */
333  unsigned char smclas;
334};
335
336/*  Flags for xcoff_link_hash_entry.  */
337
338/* Symbol is referenced by a regular object. */
339#define XCOFF_REF_REGULAR      0x00000001
340/* Symbol is defined by a regular object. */
341#define XCOFF_DEF_REGULAR      0x00000002
342/* Symbol is defined by a dynamic object. */
343#define XCOFF_DEF_DYNAMIC      0x00000004
344/* Symbol is used in a reloc being copied into the .loader section.  */
345#define XCOFF_LDREL            0x00000008
346/* Symbol is the entry point.  */
347#define XCOFF_ENTRY            0x00000010
348/* Symbol is for a function and is the target of a relocation.
349   The relocation may or may not be a branch-type relocation.  */
350#define XCOFF_CALLED           0x00000020
351/* Symbol needs the TOC entry filled in.  */
352#define XCOFF_SET_TOC          0x00000040
353/* Symbol is implicitly or explicitly imported.  */
354#define XCOFF_IMPORT           0x00000080
355/* Symbol is explicitly exported.  */
356#define XCOFF_EXPORT           0x00000100
357/* Symbol has been processed by xcoff_build_ldsyms.  */
358#define XCOFF_BUILT_LDSYM      0x00000200
359/* Symbol is mentioned by a section which was not garbage collected. */
360#define XCOFF_MARK             0x00000400
361/* Symbol size is recorded in size_list list from hash table.  */
362#define XCOFF_HAS_SIZE         0x00000800
363/* Symbol is a function descriptor.  */
364#define XCOFF_DESCRIPTOR       0x00001000
365/* Multiple definitions have been for the symbol. */
366#define XCOFF_MULTIPLY_DEFINED 0x00002000
367/* Symbol is the __rtinit symbol.  */
368#define XCOFF_RTINIT           0x00004000
369/* Symbol is an imported 32 bit syscall.  */
370#define XCOFF_SYSCALL32        0x00008000
371/* Symbol is an imported 64 bit syscall.  */
372#define XCOFF_SYSCALL64        0x00010000
373/* Symbol was not explicitly defined by the time it was marked.  */
374#define XCOFF_WAS_UNDEFINED    0x00020000
375/* We have assigned an output XCOFF entry to this symbol.  */
376#define XCOFF_ALLOCATED        0x00040000
377
378/* The XCOFF linker hash table.  */
379
380#define XCOFF_NUMBER_OF_SPECIAL_SECTIONS 6
381#define XCOFF_SPECIAL_SECTION_TEXT       0
382#define XCOFF_SPECIAL_SECTION_ETEXT      1
383#define XCOFF_SPECIAL_SECTION_DATA       2
384#define XCOFF_SPECIAL_SECTION_EDATA      3
385#define XCOFF_SPECIAL_SECTION_END        4
386#define XCOFF_SPECIAL_SECTION_END2       5
387
388/* These flags indicate which of -bexpall and -bexpfull are in effect.  */
389#define XCOFF_EXPALL 1
390#define XCOFF_EXPFULL 2
391
392/* This structure is used to pass information through
393   xcoff_link_hash_traverse.  */
394
395struct xcoff_loader_info
396{
397  /* Set if a problem occurred.  */
398  bfd_boolean failed;
399
400  /* Output BFD.  */
401  bfd *output_bfd;
402
403  /* Link information structure.  */
404  struct bfd_link_info *info;
405
406  /* A mask of XCOFF_EXPALL and XCOFF_EXPFULL flags.  */
407  unsigned int auto_export_flags;
408
409  /* Number of ldsym structures.  */
410  size_t ldsym_count;
411
412  /* Size of string table.  */
413  size_t string_size;
414
415  /* String table.  */
416  char *strings;
417
418  /* Allocated size of string table.  */
419  size_t string_alc;
420};
421
422/* In case we're on a 32-bit machine, construct a 64-bit "-1" value
423   from smaller values.  Start with zero, widen, *then* decrement.  */
424#define MINUS_ONE       (((bfd_vma) 0) - 1)
425
426/* __rtinit, from /usr/include/rtinit.h.  */
427struct __rtinit
428{
429  /* Pointer to runtime linker.     
430     XXX: Is the parameter really void?  */
431  int   (*rtl) (void); 
432
433  /* Offset to array of init functions, 0 if none. */
434  int   init_offset;
435
436  /* Offset to array of fini functions, 0 if none. */             
437  int   fini_offset;           
438
439  /* Size of __RTINIT_DESCRIPTOR. This value should be used instead of
440     sizeof(__RTINIT_DESCRIPTOR). */
441  int   __rtinit_descriptor_size; 
442};
443
444#define RTINIT_DESCRIPTOR_SIZE (12)
445
446struct __rtinit_descriptor
447{
448  /* Init/fini function. */
449  int   f;
450
451  /* Offset, relative to the start of the __rtinit symbol, to name of the
452     function. */
453
454  int   name_offset;   
455
456  /* Flags */                     
457  unsigned char flags; 
458};
459
460/* Archive */
461
462#define XCOFFARMAG    "<aiaff>\012"
463#define XCOFFARMAGBIG "<bigaf>\012"
464#define SXCOFFARMAG   8
465
466/* The size of the ascii archive elements */
467#define XCOFFARMAG_ELEMENT_SIZE 12
468#define XCOFFARMAGBIG_ELEMENT_SIZE 20
469
470/* This terminates an XCOFF archive member name.  */
471
472#define XCOFFARFMAG "`\012"
473#define SXCOFFARFMAG 2
474
475/* XCOFF archives start with this (printable) structure.  */
476
477struct xcoff_ar_file_hdr
478{
479  /* Magic string.  */
480  char magic[SXCOFFARMAG];
481
482  /* Offset of the member table (decimal ASCII string).  */
483  char memoff[XCOFFARMAG_ELEMENT_SIZE];
484
485  /* Offset of the global symbol table (decimal ASCII string).  */
486  char symoff[XCOFFARMAG_ELEMENT_SIZE];
487
488  /* Offset of the first member in the archive (decimal ASCII string).  */
489  char firstmemoff[XCOFFARMAG_ELEMENT_SIZE];
490
491  /* Offset of the last member in the archive (decimal ASCII string).  */
492  char lastmemoff[XCOFFARMAG_ELEMENT_SIZE];
493
494  /* Offset of the first member on the free list (decimal ASCII
495     string).  */
496  char freeoff[XCOFFARMAG_ELEMENT_SIZE];
497};
498
499#define SIZEOF_AR_FILE_HDR (SXCOFFARMAG + 5 * XCOFFARMAG_ELEMENT_SIZE)
500
501/* This is the equivalent data structure for the big archive format.  */
502
503struct xcoff_ar_file_hdr_big
504{
505  /* Magic string.  */
506  char magic[SXCOFFARMAG];
507
508  /* Offset of the member table (decimal ASCII string).  */
509  char memoff[XCOFFARMAGBIG_ELEMENT_SIZE];
510
511  /* Offset of the global symbol table for 32-bit objects (decimal ASCII
512     string).  */
513  char symoff[XCOFFARMAGBIG_ELEMENT_SIZE];
514
515  /* Offset of the global symbol table for 64-bit objects (decimal ASCII
516     string).  */
517  char symoff64[XCOFFARMAGBIG_ELEMENT_SIZE];
518
519  /* Offset of the first member in the archive (decimal ASCII string).  */
520  char firstmemoff[XCOFFARMAGBIG_ELEMENT_SIZE];
521
522  /* Offset of the last member in the archive (decimal ASCII string).  */
523  char lastmemoff[XCOFFARMAGBIG_ELEMENT_SIZE];
524
525  /* Offset of the first member on the free list (decimal ASCII
526     string).  */
527  char freeoff[XCOFFARMAGBIG_ELEMENT_SIZE];
528};
529
530#define SIZEOF_AR_FILE_HDR_BIG (SXCOFFARMAG + 6 * XCOFFARMAGBIG_ELEMENT_SIZE)
531
532/* Each XCOFF archive member starts with this (printable) structure.  */
533
534struct xcoff_ar_hdr
535{
536  /* File size not including the header (decimal ASCII string).  */
537  char size[XCOFFARMAG_ELEMENT_SIZE];
538
539  /* File offset of next archive member (decimal ASCII string).  */
540  char nextoff[XCOFFARMAG_ELEMENT_SIZE];
541
542  /* File offset of previous archive member (decimal ASCII string).  */
543  char prevoff[XCOFFARMAG_ELEMENT_SIZE];
544
545  /* File mtime (decimal ASCII string).  */
546  char date[12];
547
548  /* File UID (decimal ASCII string).  */
549  char uid[12];
550
551  /* File GID (decimal ASCII string).  */
552  char gid[12];
553
554  /* File mode (octal ASCII string).  */
555  char mode[12];
556
557  /* Length of file name (decimal ASCII string).  */
558  char namlen[4];
559
560  /* This structure is followed by the file name.  The length of the
561     name is given in the namlen field.  If the length of the name is
562     odd, the name is followed by a null byte.  The name and optional
563     null byte are followed by XCOFFARFMAG, which is not included in
564     namlen.  The contents of the archive member follow; the number of
565     bytes is given in the size field.  */
566};
567
568#define SIZEOF_AR_HDR (3 * XCOFFARMAG_ELEMENT_SIZE + 4 * 12 + 4)
569
570/* The equivalent for the big archive format.  */
571
572struct xcoff_ar_hdr_big
573{
574  /* File size not including the header (decimal ASCII string).  */
575  char size[XCOFFARMAGBIG_ELEMENT_SIZE];
576
577  /* File offset of next archive member (decimal ASCII string).  */
578  char nextoff[XCOFFARMAGBIG_ELEMENT_SIZE];
579
580  /* File offset of previous archive member (decimal ASCII string).  */
581  char prevoff[XCOFFARMAGBIG_ELEMENT_SIZE];
582
583  /* File mtime (decimal ASCII string).  */
584  char date[12];
585
586  /* File UID (decimal ASCII string).  */
587  char uid[12];
588
589  /* File GID (decimal ASCII string).  */
590  char gid[12];
591
592  /* File mode (octal ASCII string).  */
593  char mode[12];
594
595  /* Length of file name (decimal ASCII string).  */
596  char namlen[4];
597
598  /* This structure is followed by the file name.  The length of the
599     name is given in the namlen field.  If the length of the name is
600     odd, the name is followed by a null byte.  The name and optional
601     null byte are followed by XCOFFARFMAG, which is not included in
602     namlen.  The contents of the archive member follow; the number of
603     bytes is given in the size field.  */
604};
605
606#define SIZEOF_AR_HDR_BIG (3 * XCOFFARMAGBIG_ELEMENT_SIZE + 4 * 12 + 4)
607
608/* We often have to distinguish between the old and big file format.
609   Make it a bit cleaner.  We can use `xcoff_ardata' here because the
610   `hdr' member has the same size and position in both formats. 
611   <bigaf> is the default format, return TRUE even when xcoff_ardata is
612   NULL. */
613#ifndef SMALL_ARCHIVE
614/* Creates big archives by default */
615#define xcoff_big_format_p(abfd) \
616  ((NULL != bfd_ardata (abfd) && NULL == xcoff_ardata (abfd)) || \
617   ((NULL != bfd_ardata (abfd)) && \
618    (NULL != xcoff_ardata (abfd)) && \
619    (xcoff_ardata (abfd)->magic[1] == 'b')))
620#else
621/* Creates small archives by default. */
622#define xcoff_big_format_p(abfd) \
623  (((NULL != bfd_ardata (abfd)) && \
624    (NULL != xcoff_ardata (abfd)) && \
625    (xcoff_ardata (abfd)->magic[1] == 'b')))
626#endif
627
628/* We store a copy of the xcoff_ar_file_hdr in the tdata field of the
629   artdata structure.  Similar for the big archive.  */
630#define xcoff_ardata(abfd) \
631  ((struct xcoff_ar_file_hdr *) bfd_ardata (abfd)->tdata)
632#define xcoff_ardata_big(abfd) \
633  ((struct xcoff_ar_file_hdr_big *) bfd_ardata (abfd)->tdata)
634
635/* We store a copy of the xcoff_ar_hdr in the arelt_data field of an
636   archive element.  Similar for the big archive.  */
637#define arch_eltdata(bfd) ((struct areltdata *) ((bfd)->arelt_data))
638#define arch_xhdr(bfd) \
639  ((struct xcoff_ar_hdr *) arch_eltdata (bfd)->arch_header)
640#define arch_xhdr_big(bfd) \
641  ((struct xcoff_ar_hdr_big *) arch_eltdata (bfd)->arch_header)
642
643/* True if symbols of class CLASS are external.  */
644#define EXTERN_SYM_P(CLASS) \
645  ((CLASS) == C_EXT || (CLASS) == C_AIX_WEAKEXT)
646
647#endif /* _INTERNAL_XCOFF_H */
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