? ldint.info Index: ld.texinfo =================================================================== RCS file: /cvs/src/src/ld/ld.texinfo,v retrieving revision 1.74 diff -u -r1.74 ld.texinfo --- ld.texinfo 23 Oct 2002 13:24:10 -0000 1.74 +++ ld.texinfo 7 Nov 2002 21:48:39 -0000 @@ -1808,7 +1808,11 @@ There are several ways to address this difficulty, regardless of the data type of the exported variable: -One solution is to force one of the 'constants' to be a variable -- +One way is to use --enable-runtime-pseudo-reloc switch. This leaves the task +of adjusting references in your client code for runtime environment, so +this method works only when runtime environtment supports this feature. + +Second solution is to force one of the 'constants' to be a variable -- that is, unknown and un-optimizable at compile time. For arrays, there are two possibilities: a) make the indexee (the array's address) a variable, or b) make the 'constant' index a variable. Thus: @@ -1844,7 +1848,7 @@ @{ volatile long long * local_ll=&extern_ll; *local_ll @} @end example -A second method of dealing with this difficulty is to abandon +A third method of dealing with this difficulty is to abandon 'auto-import' for the offending symbol and mark it with @code{__declspec(dllimport)}. However, in practice that requires using compile-time #defines to indicate whether you are @@ -1895,7 +1899,7 @@ @} @end example -A third way to avoid this problem is to re-code your +A fouth way to avoid this problem is to re-code your library to use a functional interface rather than a data interface for the offending variables (e.g. set_foo() and get_foo() accessor functions). @@ -1904,6 +1908,17 @@ @item --disable-auto-import Do not attempt to do sophisticalted linking of @code{_symbol} to @code{__imp__symbol} for DATA imports from DLLs. + +@kindex --enable-runtime-pseudo-reloc +@item --enable-runtime-pseudo-reloc +If your code contains expressions described in --enable-auto-import section, +that is, DATA imports from DLL with non-zero offset, this switch will create +a vector of 'runtime pseudo relocations' which can be used by runtime +environment to adjust references to such data in your client code. + +@kindex --disable-runtime-pseudo-reloc +@item --disable-runtime-pseudo-reloc +Do not create pseudo relocations for non-zero offset DATA imports from DLLs. @kindex --enable-extra-pe-debug @item --enable-extra-pe-debug Index: ldmain.c =================================================================== RCS file: /cvs/src/src/ld/ldmain.c,v retrieving revision 1.52 diff -u -r1.52 ldmain.c --- ldmain.c 30 Oct 2002 03:57:38 -0000 1.52 +++ ldmain.c 7 Nov 2002 21:48:47 -0000 @@ -261,8 +261,8 @@ link_info.eh_frame_hdr = false; link_info.flags = (bfd_vma) 0; link_info.flags_1 = (bfd_vma) 0; - link_info.pei386_auto_import = false; link_info.pei386_auto_import = -1; + link_info.pei386_runtime_pseudo_reloc = false; link_info.combreloc = true; link_info.spare_dynamic_tags = 5; link_info.common_skip_ar_aymbols = bfd_link_common_skip_none; Index: pe-dll.c =================================================================== RCS file: /cvs/src/src/ld/pe-dll.c,v retrieving revision 1.45 diff -u -r1.45 pe-dll.c --- pe-dll.c 6 Nov 2002 19:36:20 -0000 1.45 +++ pe-dll.c 7 Nov 2002 21:49:01 -0000 @@ -141,6 +141,7 @@ static struct sec *edata_s, *reloc_s; static unsigned char *edata_d, *reloc_d; static size_t edata_sz, reloc_sz; +static int runtime_pseudo_relocs_created = 0; typedef struct { @@ -303,6 +304,10 @@ static char *make_import_fixup_mark PARAMS ((arelent *)); static bfd *make_import_fixup_entry PARAMS ((const char *, const char *, const char *, bfd *)); +static bfd *make_runtime_pseudo_reloc + PARAMS ((const char *, const char *, int, bfd *)); +static bfd *pe_create_runtime_relocator_reference + PARAMS ((bfd *parent)); static unsigned int pe_get16 PARAMS ((bfd *, int)); static unsigned int pe_get32 PARAMS ((bfd *, int)); static unsigned int pe_as32 PARAMS ((void *)); @@ -2092,15 +2097,112 @@ return abfd; } +/* .section .rdata_runtime_pseudo_reloc + .long addend + .rva __fuNN_SYM (pointer to reference (address) in text) */ + +static bfd * +make_runtime_pseudo_reloc (name, fixup_name, addend, parent) + const char *name ATTRIBUTE_UNUSED; + const char *fixup_name; + int addend; + bfd *parent; +{ + asection *rt_rel; + unsigned char *rt_rel_d; + char *oname; + bfd *abfd; + + oname = (char *) xmalloc (20); + sprintf (oname, "rtr%06d.o", tmp_seq); + tmp_seq++; + + abfd = bfd_create (oname, parent); + bfd_find_target (pe_details->object_target, abfd); + bfd_make_writable (abfd); + + bfd_set_format (abfd, bfd_object); + bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0); + + symptr = 0; + symtab = (asymbol **) xmalloc (2 * sizeof (asymbol *)); + rt_rel = quick_section (abfd, ".rdata_runtime_pseudo_reloc", SEC_HAS_CONTENTS, 2); + + quick_symbol (abfd, "", fixup_name, "", UNDSEC, BSF_GLOBAL, 0); + + bfd_set_section_size (abfd, rt_rel, 8); + rt_rel_d = (unsigned char *) xmalloc (8); + rt_rel->contents = rt_rel_d; + memset (rt_rel_d, 0, 8); + bfd_put_32 (abfd, addend, rt_rel_d); + + quick_reloc (abfd, 4, BFD_RELOC_RVA, 1); + save_relocs (rt_rel); + + bfd_set_symtab (abfd, symtab, symptr); + + bfd_set_section_contents (abfd, rt_rel, rt_rel_d, 0, 8); + + bfd_make_readable (abfd); + return abfd; +} + +/* .section .rdata + .rva __pei386_runtime_relocator */ + +static bfd * +pe_create_runtime_relocator_reference (parent) + bfd *parent; +{ + asection *extern_rt_rel; + unsigned char *extern_rt_rel_d; + char *oname; + bfd *abfd; + + oname = (char *) xmalloc (20); + sprintf (oname, "ertr%06d.o", tmp_seq); + tmp_seq++; + + abfd = bfd_create (oname, parent); + bfd_find_target (pe_details->object_target, abfd); + bfd_make_writable (abfd); + + bfd_set_format (abfd, bfd_object); + bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0); + + symptr = 0; + symtab = (asymbol **) xmalloc (2 * sizeof (asymbol *)); + extern_rt_rel = quick_section (abfd, ".rdata", SEC_HAS_CONTENTS, 2); + + quick_symbol (abfd, "", "__pei386_runtime_relocator", "", UNDSEC, BSF_NO_FLAGS, 0); + + bfd_set_section_size (abfd, extern_rt_rel, 4); + extern_rt_rel_d = (unsigned char *) xmalloc (4); + extern_rt_rel->contents = extern_rt_rel_d; + + quick_reloc (abfd, 0, BFD_RELOC_RVA, 1); + save_relocs (extern_rt_rel); + + bfd_set_symtab (abfd, symtab, symptr); + + bfd_set_section_contents (abfd, extern_rt_rel, extern_rt_rel_d, 0, 4); + + bfd_make_readable (abfd); + return abfd; +} + void -pe_create_import_fixup (rel) +pe_create_import_fixup (rel, s, addend) arelent *rel; + asection *s; + int addend; { char buf[300]; struct symbol_cache_entry *sym = *rel->sym_ptr_ptr; struct bfd_link_hash_entry *name_thunk_sym; const char *name = sym->name; char *fixup_name = make_import_fixup_mark (rel); + bfd *b; sprintf (buf, U ("_nm_thnk_%s"), name); @@ -2115,14 +2217,38 @@ config.text_read_only = false; } - { - extern char * pe_data_import_dll; - char * dll_symname = pe_data_import_dll ? pe_data_import_dll : "unknown"; + if (addend == 0 || link_info.pei386_runtime_pseudo_reloc) + { + extern char * pe_data_import_dll; + char * dll_symname = pe_data_import_dll ? pe_data_import_dll : "unknown"; - bfd *b = make_import_fixup_entry (name, fixup_name, dll_symname, - output_bfd); - add_bfd_to_link (b, b->filename, &link_info); - } + b = make_import_fixup_entry (name, fixup_name, dll_symname, output_bfd); + add_bfd_to_link (b, b->filename, &link_info); + } + + if (addend != 0) + { + if (link_info.pei386_runtime_pseudo_reloc) + { + if (pe_dll_extra_pe_debug) + printf ("creating runtime pseudo-reloc entry for %s (addend=%d)\n", + fixup_name, addend); + b = make_runtime_pseudo_reloc (name, fixup_name, addend, output_bfd); + add_bfd_to_link (b, b->filename, &link_info); + if (runtime_pseudo_relocs_created == 0) + { + b = pe_create_runtime_relocator_reference (output_bfd); + add_bfd_to_link (b, b->filename, &link_info); + } + runtime_pseudo_relocs_created++; + } + else + { + einfo (_("%C: variable '%T' can't be auto-imported. Please read the documentation for ld's --enable-auto-import for details.\n"), + s->owner, s, rel->address, sym->name); + einfo ("%X"); + } + } } Index: pe-dll.h =================================================================== RCS file: /cvs/src/src/ld/pe-dll.h,v retrieving revision 1.8 diff -u -r1.8 pe-dll.h --- pe-dll.h 8 Jun 2002 07:39:45 -0000 1.8 +++ pe-dll.h 7 Nov 2002 21:49:01 -0000 @@ -50,5 +50,5 @@ const char *name, int (*cb) (arelent *, asection *))); -extern void pe_create_import_fixup PARAMS ((arelent * rel)); +extern void pe_create_import_fixup PARAMS ((arelent * rel, asection * s, int addend)); #endif /* PE_DLL_H */ Index: emultempl/pe.em =================================================================== RCS file: /cvs/src/src/ld/emultempl/pe.em,v retrieving revision 1.68 diff -u -r1.68 pe.em --- emultempl/pe.em 6 Nov 2002 19:36:20 -0000 1.68 +++ emultempl/pe.em 7 Nov 2002 21:49:16 -0000 @@ -174,6 +174,7 @@ config.dynamic_link = true; config.has_shared = 1; link_info.pei386_auto_import = -1; + link_info.pei386_runtime_pseudo_reloc = false; #if (PE_DEF_SUBSYSTEM == 9) || (PE_DEF_SUBSYSTEM == 2) #if defined TARGET_IS_mipspe || defined TARGET_IS_armpe @@ -222,6 +223,10 @@ #define OPTION_DLL_DISABLE_AUTO_IMPORT (OPTION_DLL_ENABLE_AUTO_IMPORT + 1) #define OPTION_ENABLE_EXTRA_PE_DEBUG (OPTION_DLL_DISABLE_AUTO_IMPORT + 1) #define OPTION_EXCLUDE_LIBS (OPTION_ENABLE_EXTRA_PE_DEBUG + 1) +#define OPTION_DLL_ENABLE_RUNTIME_PSEUDO_RELOC \ + (OPTION_EXCLUDE_LIBS + 1) +#define OPTION_DLL_DISABLE_RUNTIME_PSEUDO_RELOC \ + (OPTION_DLL_ENABLE_RUNTIME_PSEUDO_RELOC + 1) static struct option longopts[] = { /* PE options */ @@ -263,6 +268,8 @@ {"enable-auto-import", no_argument, NULL, OPTION_DLL_ENABLE_AUTO_IMPORT}, {"disable-auto-import", no_argument, NULL, OPTION_DLL_DISABLE_AUTO_IMPORT}, {"enable-extra-pe-debug", no_argument, NULL, OPTION_ENABLE_EXTRA_PE_DEBUG}, + {"enable-runtime-pseudo-reloc", no_argument, NULL, OPTION_DLL_ENABLE_RUNTIME_PSEUDO_RELOC}, + {"disable-runtime-pseudo-reloc", no_argument, NULL, OPTION_DLL_DISABLE_RUNTIME_PSEUDO_RELOC}, #endif {NULL, no_argument, NULL, 0} }; @@ -352,6 +359,10 @@ fprintf (file, _(" --enable-auto-import Do sophistcated linking of _sym to \n\ __imp_sym for DATA references\n")); fprintf (file, _(" --disable-auto-import Do not auto-import DATA items from DLLs\n")); + fprintf (file, _(" --enable-runtime-pseudo-reloc Work around auto-import limitations by\n\ + adding pseudo-relocations resolved at runtime.\n")); + fprintf (file, _(" --disable-runtime-pseudo-reloc Do not add runtime pseudo-relocations for\n\ + auto-imported DATA.\n")); fprintf (file, _(" --enable-extra-pe-debug Enable verbose debug output when building\n\ or linking to DLLs (esp. auto-import)\n")); #endif @@ -633,6 +644,12 @@ case OPTION_DLL_DISABLE_AUTO_IMPORT: link_info.pei386_auto_import = 0; break; + case OPTION_DLL_ENABLE_RUNTIME_PSEUDO_RELOC: + link_info.pei386_runtime_pseudo_reloc = 1; + break; + case OPTION_DLL_DISABLE_RUNTIME_PSEUDO_RELOC: + link_info.pei386_runtime_pseudo_reloc = 0; + break; case OPTION_ENABLE_EXTRA_PE_DEBUG: pe_dll_extra_pe_debug = 1; break; @@ -877,15 +894,7 @@ einfo (_("%C: Cannot get section contents - auto-import exception\n"), s->owner, s, rel->address); - if (addend == 0) - pe_create_import_fixup (rel); - else - { - einfo (_("%C: variable '%T' can't be auto-imported. Please read the documentation for ld's --enable-auto-import for details.\n"), - s->owner, s, rel->address, sym->name); - einfo ("%X"); - } - + pe_create_import_fixup (rel, s, addend); return 1; }