diff options
| -rw-r--r-- | bfd/ChangeLog | 18 | ||||
| -rw-r--r-- | bfd/elf32-cris.c | 89 |
2 files changed, 82 insertions, 25 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 50e2f3d..595dd3f 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,21 @@ +2004-03-22 Hans-Peter Nilsson <hp@axis.com> + + * elf32-cris.c (cris_elf_relocate_section) <case R_CRIS_16_GOTPLT, + R_CRIS_16_GOTPLT>: Also error if there's no PLT for a symbol + not defined by the executable, or defined in a DSO. + <eliding run-time relocation of .got>: Initialize GOT entry for a + function symbol or ELF_LINK_HASH_NEEDS_PLT statically in an + executable. + (cris_elf_gc_sweep_hook): Improve fallthrough marking. + (elf_cris_try_fold_plt_to_got): Improve head comment. Do not fold + a PLT reloc to GOT for an executable. + (elf_cris_adjust_dynamic_symbol): Only fold a .got.plt entry with + .got for a DSO and explain why. + (elf_cris_discard_excess_program_dynamics): Also lose GOT-relocs + and unreferenced symbols for which a PLT is defined. Adjust + dynamic-symbol pruning correspondingly, to make sure we don't lose + a dynamic symbol also defined by a DSO. + 2004-03-22 Alan Modra <amodra@bigpond.net.au> * elf-bfd.h (RELOC_FOR_GLOBAL_SYMBOL): Add input_bfd, input_section diff --git a/bfd/elf32-cris.c b/bfd/elf32-cris.c index 18f87f4..b851392 100644 --- a/bfd/elf32-cris.c +++ b/bfd/elf32-cris.c @@ -960,11 +960,25 @@ cris_elf_relocate_section (output_bfd, info, input_bfd, input_section, statically linking PIC code, or when using -Bsymbolic. Check that we instead have a GOT entry as done for us by elf_cris_adjust_dynamic_symbol, and drop through into the - ordinary GOT cases. */ - if (h != NULL && h->got.offset == (bfd_vma) -1) + ordinary GOT cases. This must not happen for the + executable, because any reference it does to a function + that is satisfied by a DSO must generate a PLT. We assume + these call-specific relocs don't address non-functions. */ + if (h != NULL + && (h->got.offset == (bfd_vma) -1 + || (!info->shared + && !((h->elf_link_hash_flags + & ELF_LINK_HASH_DEF_REGULAR) != 0 + || ((h->elf_link_hash_flags + & ELF_LINK_HASH_DEF_DYNAMIC) == 0 + && h->root.type == bfd_link_hash_undefweak))))) { (*_bfd_error_handler) - (_("%s: No PLT nor GOT for relocation %s against symbol `%s' from %s section"), + ((h->got.offset == (bfd_vma) -1) + ? _("%s: No PLT nor GOT for relocation %s against\ + symbol `%s' from %s section") + : _("%s: No PLT for relocation %s against\ + symbol `%s' from %s section"), bfd_archive_filename (input_bfd), cris_elf_howto_table[r_type].name, symname[0] != '\0' ? symname : _("[whose name is lost]"), @@ -996,18 +1010,25 @@ cris_elf_relocate_section (output_bfd, info, input_bfd, input_section, if (!elf_hash_table (info)->dynamic_sections_created || (! info->shared - && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)) + && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) + || h->type == STT_FUNC + || (h->elf_link_hash_flags + & ELF_LINK_HASH_NEEDS_PLT))) || (info->shared && (info->symbolic || h->dynindx == -1) && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))) { /* This wasn't checked above for ! info->shared, but - must hold there if we get here; the symbol must be - defined in the regular program, or be undefweak. */ + must hold there if we get here; the symbol must + be defined in the regular program or be undefweak + or be a function or otherwise need a PLT. */ BFD_ASSERT (!elf_hash_table (info)->dynamic_sections_created || info->shared || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0 + || h->type == STT_FUNC + || (h->elf_link_hash_flags + & ELF_LINK_HASH_NEEDS_PLT) || h->root.type == bfd_link_hash_undefweak); /* This is actually a static link, or it is a @@ -1511,12 +1532,15 @@ elf_cris_finish_dynamic_symbol (output_bfd, info, h, sym) } } - /* We don't emit .got relocs for symbols that aren't in the - dynamic-symbols table for an ordinary program and are either defined - by the program or are undefined weak symbols. */ + /* For an ordinary program, we emit .got relocs only for symbols that + are in the dynamic-symbols table and are either defined by the + program or are undefined weak symbols, or are function symbols + where we do not output a PLT: the PLT reloc was output above and all + references to the function symbol are redirected to the PLT. */ if (h->got.offset != (bfd_vma) -1 && (info->shared || (h->dynindx != -1 + && h->plt.offset == (bfd_vma) -1 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0 && h->root.type != bfd_link_hash_undefweak))) { @@ -1838,13 +1862,12 @@ cris_elf_gc_sweep_hook (abfd, info, sec, relocs) r_symndx = ELF32_R_SYM (rel->r_info); if (r_symndx < symtab_hdr->sh_info) goto local_got_reloc; - + /* Fall through. */ case R_CRIS_32_PLT_GOTREL: /* FIXME: We don't garbage-collect away the .got section. */ if (local_got_refcounts != NULL) local_got_refcounts[-1]--; /* Fall through. */ - case R_CRIS_8_PCREL: case R_CRIS_16_PCREL: case R_CRIS_32_PCREL: @@ -1929,16 +1952,22 @@ elf_cris_adjust_gotplt_to_got (h, p) want to do this: - When all PLT references are GOTPLT references, and there are GOT - references. We don't have to generate a PLT at all. + references, and this is not the executable. We don't have to + generate a PLT at all. - - When there are both (ordinary) PLT references and GOT references. + - When there are both (ordinary) PLT references and GOT references, + and this isn't the executable. We want to make the PLT reference use the ordinary GOT entry rather - than a run-time dynamically resolved GOTPLT entry (since the GOT - entry will have to be resolved at startup anyway). + than R_CRIS_JUMP_SLOT, a run-time dynamically resolved GOTPLT entry, + since the GOT entry will have to be resolved at startup anyway. Though the latter case is handled when room for the PLT is allocated, not here. + By folding into the GOT, we may need a round-trip to a PLT in the + executable for calls, a loss in performance. Still, losing a + reloc is a win in size and at least in start-up time. + Note that this function is called before symbols are forced local by version scripts. The differing cases are handled by elf_cris_hide_symbol. */ @@ -2045,10 +2074,14 @@ elf_cris_adjust_dynamic_symbol (info, h) info); } - /* If there are only GOT references and GOTPLT references to this - PLT entry, get rid of the PLT. */ - if (! elf_cris_try_fold_plt_to_got ((struct elf_cris_link_hash_entry *) - h, info)) + /* If we had a R_CRIS_GLOB_DAT that didn't have to point to a PLT; + where a pointer-equivalent symbol was unimportant (i.e. more + like R_CRIS_JUMP_SLOT after symbol evaluation) we could get rid + of the PLT. We can't for the executable, because the GOT + entries will point to the PLT there (and be constant). */ + if (info->shared + && !elf_cris_try_fold_plt_to_got ((struct elf_cris_link_hash_entry*) + h, info)) return FALSE; /* GC or folding may have rendered this entry unused. */ @@ -2086,8 +2119,11 @@ elf_cris_adjust_dynamic_symbol (info, h) /* If there's already a GOT entry, use that, not a .got.plt. A GOT field still has a reference count when we get here; it's - not yet changed to an offset. */ - if (h->got.refcount > 0) + not yet changed to an offset. We can't do this for an + executable, because then the reloc associated with the PLT + would get a non-PLT reloc pointing to the PLT. FIXME: Move + this to elf_cris_try_fold_plt_to_got. */ + if (info->shared && h->got.refcount > 0) { h->got.refcount += h->plt.refcount; @@ -2860,9 +2896,11 @@ elf_cris_discard_excess_program_dynamics (h, inf) /* If we're not creating a shared library and have a symbol which is referred to by .got references, but the symbol is defined locally, - (or rather, not not defined by a DSO) then lose the reloc for the - .got (don't allocate room for it). */ - if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0) + (or rather, not defined by a DSO) then lose the reloc for the .got + (don't allocate room for it). Likewise for relocs for something + for which we create a PLT. */ + if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0 + || h->root.plt.refcount > 0) { if (h->root.got.refcount > 0 /* The size of this section is only valid and in sync with the @@ -2888,7 +2926,8 @@ elf_cris_discard_excess_program_dynamics (h, inf) introduce new problems. Of course we don't do this if we're exporting all dynamic symbols. */ if (! info->export_dynamic - && (h->root.elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0) + && (h->root.elf_link_hash_flags + & (ELF_LINK_HASH_DEF_DYNAMIC|ELF_LINK_HASH_REF_DYNAMIC)) == 0) { h->root.dynindx = -1; _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr, |