* xcofflink.c (XCOFF_DESCRIPTOR): Define.
(struct xcoff_link_hash_table): Add descriptor_section and special_sections fields. (_bfd_xcoff_bfd_link_hash_table_create): Initialize new fields. (xcoff_link_add_symbols): Set linkage section alignment. Create descriptor section. Check for magic symbol names (_text, etc.), and record them in special_sections if found. Set XCOFF_DESCRIPTOR flag for a function descriptor, and set its descriptor field to point back to the function code symbol. (xcoff_sweep): Always mark the special descriptor_section. (bfd_xcoff_export_symbol): Check whether the symbol might be a function descriptor, and mark it if it is. (bfd_xcoff_size_dynamic_sections): Add new special_sections parameter, and fill it in. Allocate space for the descriptor section. (xcoff_build_ldsyms): Set XCOFF_DEF_REGULAR flag when defining global linkage code. If an undefined function descriptor is exported, arrange to define it. Warn about any other undefined exported symbol. (_bfd_xcoff_bfd_final_link): Write out the descriptor section. (xcoff_write_global_symbol): Create a function descriptor when necessary. * bfd-in.h (bfd_xcoff_size_dynamic_sections): Update declaration. * bfd-in2.h: Rebuild.
This commit is contained in:
Ian Lance Taylor
parent
0e829f1854
commit
ee17481566
2 changed files with 311 additions and 5 deletions
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@ -1,3 +1,30 @@
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Thu Nov 9 13:01:31 1995 Ian Lance Taylor <ian@cygnus.com>
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* xcofflink.c (XCOFF_DESCRIPTOR): Define.
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(struct xcoff_link_hash_table): Add descriptor_section and
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special_sections fields.
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(_bfd_xcoff_bfd_link_hash_table_create): Initialize new fields.
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(xcoff_link_add_symbols): Set linkage section alignment. Create
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descriptor section. Check for magic symbol names (_text, etc.),
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and record them in special_sections if found. Set
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XCOFF_DESCRIPTOR flag for a function descriptor, and set its
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descriptor field to point back to the function code symbol.
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(xcoff_sweep): Always mark the special descriptor_section.
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(bfd_xcoff_export_symbol): Check whether the symbol might be a
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function descriptor, and mark it if it is.
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(bfd_xcoff_size_dynamic_sections): Add new special_sections
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parameter, and fill it in. Allocate space for the descriptor
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section.
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(xcoff_build_ldsyms): Set XCOFF_DEF_REGULAR flag when defining
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global linkage code. If an undefined function descriptor is
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exported, arrange to define it. Warn about any other undefined
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exported symbol.
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(_bfd_xcoff_bfd_final_link): Write out the descriptor section.
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(xcoff_write_global_symbol): Create a function descriptor when
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necessary.
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* bfd-in.h (bfd_xcoff_size_dynamic_sections): Update declaration.
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* bfd-in2.h: Rebuild.
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Thu Nov 9 08:40:23 1995 Kim Knuttila <krk@cygnus.com>
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* coff-ppc.c (ppc_coff_link_hash_entry): new types for hashing
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289
bfd/xcofflink.c
289
bfd/xcofflink.c
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@ -261,7 +261,9 @@ struct xcoff_link_hash_entry
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} u;
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/* If this symbol is a function entry point which is called, this
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field holds a pointer to the function descriptor. */
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field holds a pointer to the function descriptor. If this symbol
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is a function descriptor, this field holds a pointer to the
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function entry point. */
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struct xcoff_link_hash_entry *descriptor;
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/* The .loader symbol table entry, if there is one. */
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@ -296,6 +298,8 @@ struct xcoff_link_hash_entry
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#define XCOFF_MARK (02000)
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/* Symbol size is recorded in size_list list from hash table. */
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#define XCOFF_HAS_SIZE (04000)
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/* Symbol is a function descriptor. */
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#define XCOFF_DESCRIPTOR (010000)
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/* The storage mapping class. */
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unsigned char smclas;
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@ -332,6 +336,10 @@ struct xcoff_link_hash_table
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linkage code. */
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asection *toc_section;
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/* The .ds section we use to hold function descriptors which we
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create for exported symbols. */
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asection *descriptor_section;
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/* The list of import files. */
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struct xcoff_import_file *imports;
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@ -351,6 +359,9 @@ struct xcoff_link_hash_table
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struct xcoff_link_hash_entry *h;
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bfd_size_type size;
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} *size_list;
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/* Magic sections: _text, _etext, _data, _edata, _end, end. */
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asection *special_sections[6];
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};
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/* Information we keep for each section in the output file during the
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@ -627,10 +638,12 @@ _bfd_xcoff_bfd_link_hash_table_create (abfd)
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memset (&ret->ldhdr, 0, sizeof (struct internal_ldhdr));
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ret->linkage_section = NULL;
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ret->toc_section = NULL;
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ret->descriptor_section = NULL;
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ret->imports = NULL;
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ret->file_align = 0;
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ret->textro = false;
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ret->gc = false;
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memset (ret->special_sections, 0, sizeof ret->special_sections);
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/* The linker will always generate a full a.out header. We need to
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record that fact now, before the sizeof_headers routine could be
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@ -978,6 +991,7 @@ xcoff_link_add_symbols (abfd, info)
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goto error_return;
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xcoff_hash_table (info)->linkage_section = lsec;
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lsec->flags |= SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
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lsec->alignment_power = 2;
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}
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/* Likewise for the TOC section. */
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if (xcoff_hash_table (info)->toc_section == NULL)
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@ -991,6 +1005,18 @@ xcoff_link_add_symbols (abfd, info)
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tsec->flags |= SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
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tsec->alignment_power = 2;
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}
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/* Likewise for the descriptor section. */
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if (xcoff_hash_table (info)->descriptor_section == NULL)
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{
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asection *dsec;
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dsec = bfd_make_section_anyway (abfd, ".ds");
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if (dsec == NULL)
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goto error_return;
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xcoff_hash_table (info)->descriptor_section = dsec;
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dsec->flags |= SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
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dsec->alignment_power = 2;
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}
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/* Likewise for the .debug section. */
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if (xcoff_hash_table (info)->debug_section == NULL)
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{
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@ -1623,6 +1649,33 @@ xcoff_link_add_symbols (abfd, info)
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break;
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}
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/* Check for magic symbol names. */
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if ((smtyp == XTY_SD || smtyp == XTY_CM)
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&& aux.x_csect.x_smclas != XMC_TC)
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{
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int i;
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i = -1;
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if (name[0] == '_')
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{
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if (strcmp (name, "_text") == 0)
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i = 0;
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else if (strcmp (name, "_etext") == 0)
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i = 1;
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else if (strcmp (name, "_data") == 0)
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i = 2;
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else if (strcmp (name, "_edata") == 0)
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i = 3;
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else if (strcmp (name, "_end") == 0)
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i = 4;
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}
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else if (name[0] == 'e' && strcmp (name, "end") == 0)
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i = 5;
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if (i != -1)
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xcoff_hash_table (info)->special_sections[i] = csect;
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}
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/* Now we have enough information to add the symbol to the
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linker hash table. */
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@ -1800,6 +1853,10 @@ xcoff_link_add_symbols (abfd, info)
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(struct bfd_link_hash_entry **) &hds)))
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goto error_return;
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}
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hds->flags |= XCOFF_DESCRIPTOR;
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BFD_ASSERT ((hds->flags & XCOFF_CALLED) == 0
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&& (h->flags & XCOFF_DESCRIPTOR) == 0);
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hds->descriptor = h;
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h->descriptor = hds;
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}
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}
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@ -2250,6 +2307,7 @@ xcoff_sweep (info)
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|| o == xcoff_hash_table (info)->loader_section
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|| o == xcoff_hash_table (info)->linkage_section
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|| o == xcoff_hash_table (info)->toc_section
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|| o == xcoff_hash_table (info)->descriptor_section
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|| strcmp (o->name, ".debug") == 0)
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o->flags |= SEC_MARK;
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else
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@ -2411,10 +2469,51 @@ bfd_xcoff_export_symbol (output_bfd, info, harg, syscall)
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/* FIXME: I'm not at all sure what syscall is supposed to mean, so
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I'm just going to ignore it until somebody explains it. */
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/* See if this is a function descriptor. It may be one even though
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it is not so marked. */
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if ((h->flags & XCOFF_DESCRIPTOR) == 0
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&& h->root.root.string[0] != '.')
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{
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char *fnname;
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struct xcoff_link_hash_entry *hfn;
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fnname = (char *) malloc (strlen (h->root.root.string + 2));
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if (fnname == NULL)
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{
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bfd_set_error (bfd_error_no_memory);
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return false;
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}
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fnname[0] = '.';
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strcpy (fnname + 1, h->root.root.string);
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hfn = xcoff_link_hash_lookup (xcoff_hash_table (info),
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fnname, false, false, true);
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free (fnname);
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if (hfn != NULL
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&& hfn->smclas == XMC_PR
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&& (hfn->root.type == bfd_link_hash_defined
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|| hfn->root.type == bfd_link_hash_defweak))
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{
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h->flags |= XCOFF_DESCRIPTOR;
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h->descriptor = hfn;
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hfn->descriptor = h;
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}
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}
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/* Make sure we don't garbage collect this symbol. */
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if (! xcoff_mark_symbol (info, h))
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return false;
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/* If this is a function descriptor, make sure we don't garbage
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collect the associated function code. We normally don't have to
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worry about this, because the descriptor will be attached to a
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section with relocs, but if we are creating the descriptor
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ourselves those relocs will not be visible to the mark code. */
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if ((h->flags & XCOFF_DESCRIPTOR) != 0)
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{
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if (! xcoff_mark_symbol (info, h->descriptor))
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return false;
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}
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return true;
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}
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@ -2507,7 +2606,7 @@ struct xcoff_loader_info
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boolean
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bfd_xcoff_size_dynamic_sections (output_bfd, info, libpath, entry,
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file_align, maxstack, maxdata, gc,
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modtype, textro)
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modtype, textro, special_sections)
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bfd *output_bfd;
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struct bfd_link_info *info;
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const char *libpath;
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@ -2518,10 +2617,12 @@ bfd_xcoff_size_dynamic_sections (output_bfd, info, libpath, entry,
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boolean gc;
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int modtype;
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boolean textro;
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asection **special_sections;
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{
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struct xcoff_link_hash_entry *hentry;
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asection *lsec;
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struct xcoff_loader_info ldinfo;
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int i;
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size_t impsize, impcount;
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struct xcoff_import_file *fl;
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struct internal_ldhdr *ldhdr;
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@ -2595,6 +2696,19 @@ bfd_xcoff_size_dynamic_sections (output_bfd, info, libpath, entry,
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xcoff_hash_table (info)->gc = true;
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}
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/* Return special sections to the caller. */
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for (i = 0; i < 6; i++)
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{
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asection *sec;
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sec = xcoff_hash_table (info)->special_sections[i];
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if (sec != NULL
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&& gc
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&& (sec->flags & SEC_MARK) == 0)
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sec = NULL;
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special_sections[i] = sec;
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}
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if (info->input_bfds == NULL)
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{
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/* I'm not sure what to do in this bizarre case. */
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@ -2694,8 +2808,7 @@ bfd_xcoff_size_dynamic_sections (output_bfd, info, libpath, entry,
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when the corresponding normal relocs are handled in
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xcoff_link_input_bfd. */
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/* Allocate space for the global linkage section and the global toc
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section. */
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/* Allocate space for the magic sections. */
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sec = xcoff_hash_table (info)->linkage_section;
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if (sec->_raw_size > 0)
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{
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@ -2707,6 +2820,16 @@ bfd_xcoff_size_dynamic_sections (output_bfd, info, libpath, entry,
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}
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}
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sec = xcoff_hash_table (info)->toc_section;
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if (sec->_raw_size > 0)
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{
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sec->contents = (bfd_byte *) bfd_zalloc (output_bfd, sec->_raw_size);
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if (sec->contents == NULL)
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{
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bfd_set_error (bfd_error_no_memory);
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goto error_return;
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}
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}
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sec = xcoff_hash_table (info)->descriptor_section;
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if (sec->_raw_size > 0)
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{
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sec->contents = (bfd_byte *) bfd_zalloc (output_bfd, sec->_raw_size);
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@ -2877,6 +3000,7 @@ xcoff_build_ldsyms (h, p)
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h->root.u.def.section = sec;
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h->root.u.def.value = sec->_raw_size;
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h->smclas = XMC_GL;
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h->flags |= XCOFF_DEF_REGULAR;
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sec->_raw_size += XCOFF_GLINK_SIZE;
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/* The global linkage code requires a TOC entry for the
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|
@ -2902,6 +3026,53 @@ xcoff_build_ldsyms (h, p)
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}
|
||||
}
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||||
|
||||
/* If this symbol is exported, but not defined, we need to try to
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define it. */
|
||||
if ((h->flags & XCOFF_EXPORT) != 0
|
||||
&& (h->flags & XCOFF_IMPORT) == 0
|
||||
&& (h->flags & XCOFF_DEF_REGULAR) == 0
|
||||
&& (h->flags & XCOFF_DEF_DYNAMIC) == 0
|
||||
&& (h->root.type == bfd_link_hash_undefined
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|| h->root.type == bfd_link_hash_undefweak))
|
||||
{
|
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if ((h->flags & XCOFF_DESCRIPTOR) != 0
|
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&& (h->descriptor->root.type == bfd_link_hash_defined
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|| h->descriptor->root.type == bfd_link_hash_defweak))
|
||||
{
|
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asection *sec;
|
||||
|
||||
/* This is an undefined function descriptor associated with
|
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a defined entry point. We can build up a function
|
||||
descriptor ourselves. Believe it or not, the AIX linker
|
||||
actually does this, and there are cases where we need to
|
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do it as well. */
|
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sec = xcoff_hash_table (ldinfo->info)->descriptor_section;
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h->root.type = bfd_link_hash_defined;
|
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h->root.u.def.section = sec;
|
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h->root.u.def.value = sec->_raw_size;
|
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h->smclas = XMC_DS;
|
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h->flags |= XCOFF_DEF_REGULAR;
|
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sec->_raw_size += 12;
|
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|
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/* A function descriptor uses two relocs: one for the
|
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associated code, and one for the TOC address. */
|
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xcoff_hash_table (ldinfo->info)->ldrel_count += 2;
|
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sec->reloc_count += 2;
|
||||
|
||||
/* We handle writing out the contents of the descriptor in
|
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xcoff_write_global_symbol. */
|
||||
}
|
||||
else
|
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{
|
||||
(*_bfd_error_handler)
|
||||
("attempt to export undefined symbol `%s'",
|
||||
h->root.root.string);
|
||||
ldinfo->failed = true;
|
||||
bfd_set_error (bfd_error_invalid_operation);
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
/* If this is still a common symbol, and it wasn't garbage
|
||||
collected, we need to actually allocate space for it in the .bss
|
||||
section. */
|
||||
|
|
@ -3528,13 +3699,18 @@ _bfd_xcoff_bfd_final_link (abfd, info)
|
|||
o->_raw_size))
|
||||
goto error_return;
|
||||
|
||||
/* Write out the global linkage section and the toc section. */
|
||||
/* Write out the magic sections. */
|
||||
o = xcoff_hash_table (info)->linkage_section;
|
||||
if (o->_raw_size > 0
|
||||
&& ! bfd_set_section_contents (abfd, o->output_section, o->contents,
|
||||
o->output_offset, o->_raw_size))
|
||||
goto error_return;
|
||||
o = xcoff_hash_table (info)->toc_section;
|
||||
if (o->_raw_size > 0
|
||||
&& ! bfd_set_section_contents (abfd, o->output_section, o->contents,
|
||||
o->output_offset, o->_raw_size))
|
||||
goto error_return;
|
||||
o = xcoff_hash_table (info)->descriptor_section;
|
||||
if (o->_raw_size > 0
|
||||
&& ! bfd_set_section_contents (abfd, o->output_section, o->contents,
|
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o->output_offset, o->_raw_size))
|
||||
|
|
@ -4857,6 +5033,109 @@ xcoff_write_global_symbol (h, p)
|
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++finfo->ldrel;
|
||||
}
|
||||
|
||||
/* If this symbol is a specially defined function descriptor, write
|
||||
it out. The first word is the address of the function code
|
||||
itself, the second word is the address of the TOC, and the third
|
||||
word is zero. */
|
||||
if ((h->flags & XCOFF_DESCRIPTOR) != 0
|
||||
&& h->root.type == bfd_link_hash_defined
|
||||
&& (h->root.u.def.section
|
||||
== xcoff_hash_table (finfo->info)->descriptor_section))
|
||||
{
|
||||
asection *sec;
|
||||
asection *osec;
|
||||
int oindx;
|
||||
bfd_byte *p;
|
||||
struct xcoff_link_hash_entry *hentry;
|
||||
asection *esec;
|
||||
struct internal_reloc *irel;
|
||||
struct internal_ldrel ldrel;
|
||||
asection *tsec;
|
||||
|
||||
sec = h->root.u.def.section;
|
||||
osec = sec->output_section;
|
||||
oindx = osec->target_index;
|
||||
p = sec->contents + h->root.u.def.value;
|
||||
|
||||
hentry = h->descriptor;
|
||||
BFD_ASSERT (hentry != NULL
|
||||
&& (hentry->root.type == bfd_link_hash_defined
|
||||
|| hentry->root.type == bfd_link_hash_defweak));
|
||||
esec = hentry->root.u.def.section;
|
||||
bfd_put_32 (output_bfd,
|
||||
(esec->output_section->vma
|
||||
+ esec->output_offset
|
||||
+ hentry->root.u.def.value),
|
||||
p);
|
||||
|
||||
irel = finfo->section_info[oindx].relocs + osec->reloc_count;
|
||||
irel->r_vaddr = (osec->vma
|
||||
+ sec->output_offset
|
||||
+ h->root.u.def.value);
|
||||
irel->r_symndx = esec->output_section->target_index;
|
||||
irel->r_type = R_POS;
|
||||
irel->r_size = 31;
|
||||
finfo->section_info[oindx].rel_hashes[osec->reloc_count] = NULL;
|
||||
++osec->reloc_count;
|
||||
|
||||
ldrel.l_vaddr = irel->r_vaddr;
|
||||
if (strcmp (esec->output_section->name, ".text") == 0)
|
||||
ldrel.l_symndx = 0;
|
||||
else if (strcmp (esec->output_section->name, ".data") == 0)
|
||||
ldrel.l_symndx = 1;
|
||||
else if (strcmp (esec->output_section->name, ".bss") == 0)
|
||||
ldrel.l_symndx = 2;
|
||||
else
|
||||
{
|
||||
(*_bfd_error_handler)
|
||||
("%s: loader reloc in unrecognized section `%s'",
|
||||
bfd_get_filename (output_bfd),
|
||||
esec->output_section->name);
|
||||
bfd_set_error (bfd_error_nonrepresentable_section);
|
||||
return false;
|
||||
}
|
||||
ldrel.l_rtype = (31 << 8) | R_POS;
|
||||
ldrel.l_rsecnm = oindx;
|
||||
xcoff_swap_ldrel_out (output_bfd, &ldrel, finfo->ldrel);
|
||||
++finfo->ldrel;
|
||||
|
||||
bfd_put_32 (output_bfd, xcoff_data (output_bfd)->toc, p + 4);
|
||||
|
||||
tsec = xcoff_data (output_bfd)->toc_section;
|
||||
|
||||
++irel;
|
||||
irel->r_vaddr = (osec->vma
|
||||
+ sec->output_offset
|
||||
+ h->root.u.def.value
|
||||
+ 4);
|
||||
irel->r_symndx = tsec->output_section->target_index;
|
||||
irel->r_type = R_POS;
|
||||
irel->r_size = 31;
|
||||
finfo->section_info[oindx].rel_hashes[osec->reloc_count] = NULL;
|
||||
++osec->reloc_count;
|
||||
|
||||
ldrel.l_vaddr = irel->r_vaddr;
|
||||
if (strcmp (tsec->output_section->name, ".text") == 0)
|
||||
ldrel.l_symndx = 0;
|
||||
else if (strcmp (tsec->output_section->name, ".data") == 0)
|
||||
ldrel.l_symndx = 1;
|
||||
else if (strcmp (tsec->output_section->name, ".bss") == 0)
|
||||
ldrel.l_symndx = 2;
|
||||
else
|
||||
{
|
||||
(*_bfd_error_handler)
|
||||
("%s: loader reloc in unrecognized section `%s'",
|
||||
bfd_get_filename (output_bfd),
|
||||
tsec->output_section->name);
|
||||
bfd_set_error (bfd_error_nonrepresentable_section);
|
||||
return false;
|
||||
}
|
||||
ldrel.l_rtype = (31 << 8) | R_POS;
|
||||
ldrel.l_rsecnm = oindx;
|
||||
xcoff_swap_ldrel_out (output_bfd, &ldrel, finfo->ldrel);
|
||||
++finfo->ldrel;
|
||||
}
|
||||
|
||||
if (h->indx >= 0)
|
||||
return true;
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue