Run --gc-sections tests only if supported.

[deliverable/binutils-gdb.git] / bfd / libcoff-in.h

/* BFD COFF object file private structure.
   Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   Free Software Foundation, Inc.
   Written by Cygnus Support.

   This file is part of BFD, the Binary File Descriptor library.

   This program 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 3 of the License, or
   (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "bfdlink.h"

/* Object file tdata; access macros.  */

#define coff_data(bfd)		      ((bfd)->tdata.coff_obj_data)
#define obj_pe(bfd)                   (coff_data (bfd)->pe)
#define obj_symbols(bfd)	      (coff_data (bfd)->symbols)
#define	obj_sym_filepos(bfd)	      (coff_data (bfd)->sym_filepos)
#define obj_relocbase(bfd)	      (coff_data (bfd)->relocbase)
#define obj_raw_syments(bfd)	      (coff_data (bfd)->raw_syments)
#define obj_raw_syment_count(bfd)     (coff_data (bfd)->raw_syment_count)
#define obj_convert(bfd)	      (coff_data (bfd)->conversion_table)
#define obj_conv_table_size(bfd)      (coff_data (bfd)->conv_table_size)
#define obj_coff_external_syms(bfd)   (coff_data (bfd)->external_syms)
#define obj_coff_keep_syms(bfd)	      (coff_data (bfd)->keep_syms)
#define obj_coff_strings(bfd)	      (coff_data (bfd)->strings)
#define obj_coff_keep_strings(bfd)    (coff_data (bfd)->keep_strings)
#define obj_coff_sym_hashes(bfd)      (coff_data (bfd)->sym_hashes)
#define obj_coff_strings_written(bfd) (coff_data (bfd)->strings_written)
#define obj_coff_local_toc_table(bfd) (coff_data (bfd)->local_toc_sym_map)

/* `Tdata' information kept for COFF files.  */

typedef struct coff_tdata
{
  struct coff_symbol_struct *symbols;	/* Symtab for input bfd.  */
  unsigned int *conversion_table;
  int conv_table_size;
  file_ptr sym_filepos;

  struct coff_ptr_struct *raw_syments;
  unsigned long raw_syment_count;

  /* These are only valid once writing has begun.  */
  long int relocbase;

  /* These members communicate important constants about the symbol table
     to GDB's symbol-reading code.  These `constants' unfortunately vary
     from coff implementation to implementation...  */
  unsigned local_n_btmask;
  unsigned local_n_btshft;
  unsigned local_n_tmask;
  unsigned local_n_tshift;
  unsigned local_symesz;
  unsigned local_auxesz;
  unsigned local_linesz;

  /* The unswapped external symbols.  May be NULL.  Read by
     _bfd_coff_get_external_symbols.  */
  void * external_syms;
  /* If this is TRUE, the external_syms may not be freed.  */
  bfd_boolean keep_syms;

  /* The string table.  May be NULL.  Read by
     _bfd_coff_read_string_table.  */
  char *strings;
  /* If this is TRUE, the strings may not be freed.  */
  bfd_boolean keep_strings;
  /* If this is TRUE, the strings have been written out already.  */
  bfd_boolean strings_written;

  /* Is this a PE format coff file?  */
  int pe;
  /* Used by the COFF backend linker.  */
  struct coff_link_hash_entry **sym_hashes;

  /* Used by the pe linker for PowerPC.  */
  int *local_toc_sym_map;

  struct bfd_link_info *link_info;

  /* Used by coff_find_nearest_line.  */
  void * line_info;

  /* A place to stash dwarf2 info for this bfd.  */
  void * dwarf2_find_line_info;

  /* The timestamp from the COFF file header.  */
  long timestamp;

  /* Copy of some of the f_flags bits in the COFF filehdr structure,
     used by ARM code.  */
  flagword flags;

  /* coff-stgo32 EXE stub header after BFD tdata has been allocated.  Its data
     is kept in internal_filehdr.go32stub beforehand.  */
  char *go32stub;
} coff_data_type;

/* Tdata for pe image files.  */
typedef struct pe_tdata
{
  coff_data_type coff;
  struct internal_extra_pe_aouthdr pe_opthdr;
  int dll;
  int has_reloc_section;
  int dont_strip_reloc;
  bfd_boolean (*in_reloc_p) (bfd *, reloc_howto_type *);
  flagword real_flags;
} pe_data_type;

#define pe_data(bfd)		((bfd)->tdata.pe_obj_data)

/* Tdata for XCOFF files.  */

struct xcoff_tdata
{
  /* Basic COFF information.  */
  coff_data_type coff;

  /* TRUE if this is an XCOFF64 file. */
  bfd_boolean xcoff64;

  /* TRUE if a large a.out header should be generated.  */
  bfd_boolean full_aouthdr;

  /* TOC value.  */
  bfd_vma toc;

  /* Index of section holding TOC.  */
  int sntoc;

  /* Index of section holding entry point.  */
  int snentry;

  /* .text alignment from optional header.  */
  int text_align_power;

  /* .data alignment from optional header.  */
  int data_align_power;

  /* modtype from optional header.  */
  short modtype;

  /* cputype from optional header.  */
  short cputype;

  /* maxdata from optional header.  */
  bfd_vma maxdata;

  /* maxstack from optional header.  */
  bfd_vma maxstack;

  /* Used by the XCOFF backend linker.  */
  asection **csects;
  long *debug_indices;
  unsigned int *lineno_counts;
  unsigned int import_file_id;
};

#define xcoff_data(abfd) ((abfd)->tdata.xcoff_obj_data)

/* We take the address of the first element of an asymbol to ensure that the
   macro is only ever applied to an asymbol.  */
#define coffsymbol(asymbol) ((coff_symbol_type *)(&((asymbol)->the_bfd)))

/* The used_by_bfd field of a section may be set to a pointer to this
   structure.  */

struct coff_section_tdata
{
  /* The relocs, swapped into COFF internal form.  This may be NULL.  */
  struct internal_reloc *relocs;
  /* If this is TRUE, the relocs entry may not be freed.  */
  bfd_boolean keep_relocs;
  /* The section contents.  This may be NULL.  */
  bfd_byte *contents;
  /* If this is TRUE, the contents entry may not be freed.  */
  bfd_boolean keep_contents;
  /* Information cached by coff_find_nearest_line.  */
  bfd_vma offset;
  unsigned int i;
  const char *function;
  /* Optional information about a COMDAT entry; NULL if not COMDAT. */
  struct coff_comdat_info *comdat;
  int line_base;
  /* A pointer used for .stab linking optimizations.  */
  void * stab_info;
  /* Available for individual backends.  */
  void * tdata;
};

/* An accessor macro for the coff_section_tdata structure.  */
#define coff_section_data(abfd, sec) \
  ((struct coff_section_tdata *) (sec)->used_by_bfd)

/* Tdata for sections in XCOFF files.  This is used by the linker.  */

struct xcoff_section_tdata
{
  /* Used for XCOFF csects created by the linker; points to the real
     XCOFF section which contains this csect.  */
  asection *enclosing;
  /* The lineno_count field for the enclosing section, because we are
     going to clobber it there.  */
  unsigned int lineno_count;
  /* The first and last symbol indices for symbols used by this csect.  */
  unsigned long first_symndx;
  unsigned long last_symndx;
};

/* An accessor macro the xcoff_section_tdata structure.  */
#define xcoff_section_data(abfd, sec) \
  ((struct xcoff_section_tdata *) coff_section_data ((abfd), (sec))->tdata)

/* Tdata for sections in PE files.  */

struct pei_section_tdata
{
  /* The virtual size of the section.  */
  bfd_size_type virt_size;
  /* The PE section flags.  */
  long pe_flags;
};

/* An accessor macro for the pei_section_tdata structure.  */
#define pei_section_data(abfd, sec) \
  ((struct pei_section_tdata *) coff_section_data ((abfd), (sec))->tdata)

/* COFF linker hash table entries.  */

struct coff_link_hash_entry
{
  struct bfd_link_hash_entry root;

  /* Symbol index in output file.  Set to -1 initially.  Set to -2 if
     there is a reloc against this symbol.  */
  long indx;

  /* Symbol type.  */
  unsigned short type;

  /* Symbol class.  */
  unsigned char symbol_class;

  /* Number of auxiliary entries.  */
  char numaux;

  /* BFD to take auxiliary entries from.  */
  bfd *auxbfd;

  /* Pointer to array of auxiliary entries, if any.  */
  union internal_auxent *aux;

  /* Flag word; legal values follow.  */
  unsigned short coff_link_hash_flags;
  /* Symbol is a PE section symbol.  */
#define COFF_LINK_HASH_PE_SECTION_SYMBOL (01)
};

/* COFF linker hash table.  */

struct coff_link_hash_table
{
  struct bfd_link_hash_table root;
  /* A pointer to information used to link stabs in sections.  */
  struct stab_info stab_info;
};

/* Look up an entry in a COFF linker hash table.  */

#define coff_link_hash_lookup(table, string, create, copy, follow)	\
  ((struct coff_link_hash_entry *)					\
   bfd_link_hash_lookup (&(table)->root, (string), (create),		\
			 (copy), (follow)))

/* Traverse a COFF linker hash table.  */

#define coff_link_hash_traverse(table, func, info)			\
  (bfd_link_hash_traverse						\
   (&(table)->root,							\
    (bfd_boolean (*) (struct bfd_link_hash_entry *, void *)) (func), \
    (info)))

/* Get the COFF linker hash table from a link_info structure.  */

#define coff_hash_table(p) ((struct coff_link_hash_table *) ((p)->hash))

/* Functions in coffgen.c.  */
extern const bfd_target *coff_object_p
  (bfd *);
extern struct bfd_section *coff_section_from_bfd_index
  (bfd *, int);
extern long coff_get_symtab_upper_bound
  (bfd *);
extern long coff_canonicalize_symtab
  (bfd *, asymbol **);
extern int coff_count_linenumbers
  (bfd *);
extern struct coff_symbol_struct *coff_symbol_from
  (bfd *, asymbol *);
extern bfd_boolean coff_renumber_symbols
  (bfd *, int *);
extern void coff_mangle_symbols
  (bfd *);
extern bfd_boolean coff_write_symbols
  (bfd *);
extern bfd_boolean coff_write_linenumbers
  (bfd *);
extern alent *coff_get_lineno
  (bfd *, asymbol *);
extern asymbol *coff_section_symbol
  (bfd *, char *);
extern bfd_boolean _bfd_coff_get_external_symbols
  (bfd *);
extern const char *_bfd_coff_read_string_table
  (bfd *);
extern bfd_boolean _bfd_coff_free_symbols
  (bfd *);
extern struct coff_ptr_struct *coff_get_normalized_symtab
  (bfd *);
extern long coff_get_reloc_upper_bound
  (bfd *, sec_ptr);
extern asymbol *coff_make_empty_symbol
  (bfd *);
extern void coff_print_symbol
  (bfd *, void * filep, asymbol *, bfd_print_symbol_type);
extern void coff_get_symbol_info
  (bfd *, asymbol *, symbol_info *ret);
extern bfd_boolean _bfd_coff_is_local_label_name
  (bfd *, const char *);
extern asymbol *coff_bfd_make_debug_symbol
  (bfd *, void *, unsigned long);
extern bfd_boolean coff_find_nearest_line
  (bfd *, asection *, asymbol **, bfd_vma, const char **,
   const char **, unsigned int *);
struct dwarf_debug_section;
extern bfd_boolean coff_find_nearest_line_with_names
  (bfd *, const struct dwarf_debug_section *, asection *, asymbol **,
   bfd_vma, const char **, const char **, unsigned int *);
extern bfd_boolean coff_find_inliner_info
  (bfd *, const char **, const char **, unsigned int *);
extern int coff_sizeof_headers
  (bfd *, struct bfd_link_info *);
extern bfd_boolean bfd_coff_reloc16_relax_section
  (bfd *, asection *, struct bfd_link_info *, bfd_boolean *);
extern bfd_byte *bfd_coff_reloc16_get_relocated_section_contents
  (bfd *, struct bfd_link_info *, struct bfd_link_order *,
   bfd_byte *, bfd_boolean, asymbol **);
extern bfd_vma bfd_coff_reloc16_get_value
  (arelent *, struct bfd_link_info *, asection *);
extern void bfd_perform_slip
  (bfd *, unsigned int, asection *, bfd_vma);

/* Functions and types in cofflink.c.  */

#define STRING_SIZE_SIZE 4

/* We use a hash table to merge identical enum, struct, and union
   definitions in the linker.  */

/* Information we keep for a single element (an enum value, a
   structure or union field) in the debug merge hash table.  */

struct coff_debug_merge_element
{
  /* Next element.  */
  struct coff_debug_merge_element *next;

  /* Name.  */
  const char *name;

  /* Type.  */
  unsigned int type;

  /* Symbol index for complex type.  */
  long tagndx;
};

/* A linked list of debug merge entries for a given name.  */

struct coff_debug_merge_type
{
  /* Next type with the same name.  */
  struct coff_debug_merge_type *next;

  /* Class of type.  */
  int type_class;

  /* Symbol index where this type is defined.  */
  long indx;

  /* List of elements.  */
  struct coff_debug_merge_element *elements;
};

/* Information we store in the debug merge hash table.  */

struct coff_debug_merge_hash_entry
{
  struct bfd_hash_entry root;

  /* A list of types with this name.  */
  struct coff_debug_merge_type *types;
};

/* The debug merge hash table.  */

struct coff_debug_merge_hash_table
{
  struct bfd_hash_table root;
};

/* Initialize a COFF debug merge hash table.  */

#define coff_debug_merge_hash_table_init(table) \
  (bfd_hash_table_init (&(table)->root, _bfd_coff_debug_merge_hash_newfunc, \
			sizeof (struct coff_debug_merge_hash_entry)))

/* Free a COFF debug merge hash table.  */

#define coff_debug_merge_hash_table_free(table) \
  (bfd_hash_table_free (&(table)->root))

/* Look up an entry in a COFF debug merge hash table.  */

#define coff_debug_merge_hash_lookup(table, string, create, copy) \
  ((struct coff_debug_merge_hash_entry *) \
   bfd_hash_lookup (&(table)->root, (string), (create), (copy)))

/* Information we keep for each section in the output file when doing
   a relocatable link.  */

struct coff_link_section_info
{
  /* The relocs to be output.  */
  struct internal_reloc *relocs;
  /* For each reloc against a global symbol whose index was not known
     when the reloc was handled, the global hash table entry.  */
  struct coff_link_hash_entry **rel_hashes;
};

/* Information that we pass around while doing the final link step.  */

struct coff_final_link_info
{
  /* General link information.  */
  struct bfd_link_info *info;
  /* Output BFD.  */
  bfd *output_bfd;
  /* Used to indicate failure in traversal routine.  */
  bfd_boolean failed;
  /* If doing "task linking" set only during the time when we want the
     global symbol writer to convert the storage class of defined global
     symbols from global to static. */
  bfd_boolean global_to_static;
  /* Hash table for long symbol names.  */
  struct bfd_strtab_hash *strtab;
  /* When doing a relocatable link, an array of information kept for
     each output section, indexed by the target_index field.  */
  struct coff_link_section_info *section_info;
  /* Symbol index of last C_FILE symbol (-1 if none).  */
  long last_file_index;
  /* Contents of last C_FILE symbol.  */
  struct internal_syment last_file;
  /* Symbol index of first aux entry of last .bf symbol with an empty
     endndx field (-1 if none).  */
  long last_bf_index;
  /* Contents of last_bf_index aux entry.  */
  union internal_auxent last_bf;
  /* Hash table used to merge debug information.  */
  struct coff_debug_merge_hash_table debug_merge;
  /* Buffer large enough to hold swapped symbols of any input file.  */
  struct internal_syment *internal_syms;
  /* Buffer large enough to hold sections of symbols of any input file.  */
  asection **sec_ptrs;
  /* Buffer large enough to hold output indices of symbols of any
     input file.  */
  long *sym_indices;
  /* Buffer large enough to hold output symbols for any input file.  */
  bfd_byte *outsyms;
  /* Buffer large enough to hold external line numbers for any input
     section.  */
  bfd_byte *linenos;
  /* Buffer large enough to hold any input section.  */
  bfd_byte *contents;
  /* Buffer large enough to hold external relocs of any input section.  */
  bfd_byte *external_relocs;
  /* Buffer large enough to hold swapped relocs of any input section.  */
  struct internal_reloc *internal_relocs;
};

/* Most COFF variants have no way to record the alignment of a
   section.  This struct is used to set a specific alignment based on
   the name of the section.  */

struct coff_section_alignment_entry
{
  /* The section name.  */
  const char *name;

  /* This is either (unsigned int) -1, indicating that the section
     name must match exactly, or it is the number of letters which
     must match at the start of the name.  */
  unsigned int comparison_length;

  /* These macros may be used to fill in the first two fields in a
     structure initialization.  */
#define COFF_SECTION_NAME_EXACT_MATCH(name) (name), ((unsigned int) -1)
#define COFF_SECTION_NAME_PARTIAL_MATCH(name) (name), (sizeof (name) - 1)

  /* Only use this entry if the default section alignment for this
     target is at least that much (as a power of two).  If this field
     is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
  unsigned int default_alignment_min;

  /* Only use this entry if the default section alignment for this
     target is no greater than this (as a power of two).  If this
     field is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
  unsigned int default_alignment_max;

#define COFF_ALIGNMENT_FIELD_EMPTY ((unsigned int) -1)

  /* The desired alignment for this section (as a power of two).  */
  unsigned int alignment_power;
};

extern struct bfd_hash_entry *_bfd_coff_link_hash_newfunc
  (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
extern bfd_boolean _bfd_coff_link_hash_table_init
  (struct coff_link_hash_table *, bfd *,
   struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
			       struct bfd_hash_table *,
			       const char *),
   unsigned int);
extern struct bfd_link_hash_table *_bfd_coff_link_hash_table_create
  (bfd *);
extern const char *_bfd_coff_internal_syment_name
  (bfd *, const struct internal_syment *, char *);
extern bfd_boolean _bfd_coff_section_already_linked
  (bfd *, asection *, struct bfd_link_info *);
extern bfd_boolean _bfd_coff_link_add_symbols
  (bfd *, struct bfd_link_info *);
extern bfd_boolean _bfd_coff_final_link
  (bfd *, struct bfd_link_info *);
extern struct internal_reloc *_bfd_coff_read_internal_relocs
  (bfd *, asection *, bfd_boolean, bfd_byte *, bfd_boolean,
   struct internal_reloc *);
extern bfd_boolean _bfd_coff_generic_relocate_section
  (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
   struct internal_reloc *, struct internal_syment *, asection **);
extern struct bfd_hash_entry *_bfd_coff_debug_merge_hash_newfunc
  (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
extern bfd_boolean _bfd_coff_write_global_sym
  (struct bfd_hash_entry *, void *);
extern bfd_boolean _bfd_coff_write_task_globals
  (struct coff_link_hash_entry *, void *);
extern bfd_boolean _bfd_coff_link_input_bfd
  (struct coff_final_link_info *, bfd *);
extern bfd_boolean _bfd_coff_reloc_link_order
  (bfd *, struct coff_final_link_info *, asection *,
   struct bfd_link_order *);


#define coff_get_section_contents_in_window \
  _bfd_generic_get_section_contents_in_window

/* Functions in xcofflink.c.  */

extern long _bfd_xcoff_get_dynamic_symtab_upper_bound
  (bfd *);
extern long _bfd_xcoff_canonicalize_dynamic_symtab
  (bfd *, asymbol **);
extern long _bfd_xcoff_get_dynamic_reloc_upper_bound
  (bfd *);
extern long _bfd_xcoff_canonicalize_dynamic_reloc
  (bfd *, arelent **, asymbol **);
extern struct bfd_link_hash_table *_bfd_xcoff_bfd_link_hash_table_create
  (bfd *);
extern void _bfd_xcoff_bfd_link_hash_table_free
  (struct bfd_link_hash_table *);
extern bfd_boolean _bfd_xcoff_bfd_link_add_symbols
  (bfd *, struct bfd_link_info *);
extern bfd_boolean _bfd_xcoff_bfd_final_link
  (bfd *, struct bfd_link_info *);
extern bfd_boolean _bfd_xcoff_define_common_symbol
  (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *);
extern bfd_boolean _bfd_ppc_xcoff_relocate_section
  (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
   struct internal_reloc *, struct internal_syment *, asection **);

/* Functions in coff-ppc.c.  FIXME: These are called by pe.em in the
   linker, and so should start with bfd and be declared in bfd.h.  */

extern bfd_boolean ppc_allocate_toc_section
  (struct bfd_link_info *);
extern bfd_boolean ppc_process_before_allocation
  (bfd *, struct bfd_link_info *);