From 6911b7dcb8ea17f8b811578dd4ac1ab7bb675e7b Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Tue, 29 Oct 2013 15:37:43 +1030 Subject: Add ELFv2 .localentry support. This defines the ELF symbol st_other field used to encode the number of instructions between a function "global entry" and its "local entry", and adds support related to the local entry offset. include/elf/ * ppc64.h (STO_PPC64_LOCAL_BIT, STO_PPC64_LOCAL_MASK): Define. (ppc64_decode_local_entry, ppc64_encode_local_entry): New functions. (PPC64_LOCAL_ENTRY_OFFSET, PPC64_SET_LOCAL_ENTRY_OFFSET): Define. bfd/ * elf64-ppc.c (struct ppc_stub_hash_entry): Add "other". (stub_hash_newfunc): Init new ppc_stub_hash_entry field, and one we forgot, "plt_ent". (ppc64_elf_add_symbol_hook): Check ELFv1 objects don't have st_other bits only valid in ELFv2. (ppc64_elf_merge_symbol_attribute): New function. (ppc_type_of_stub): Add local_off param to test branch range. (ppc_build_one_stub): Adjust destinations for ELFv2 locals. (ppc_size_one_stub, toc_adjusting_stub_needed): Similarly. (ppc64_elf_size_stubs): Pass local_off to ppc_type_of_stub. Set "other" field. (ppc64_elf_relocate_section): Adjust destination for ELFv2 local calls. gas/ * config/tc-ppc.c (md_pseudo_table): Add .localentry. (ppc_elf_localentry): New function. (ppc_force_relocation): Force relocs on all branches to localenty symbols. (ppc_fix_adjustable): Don't reduce such symbols to section+offset. binutils/ * readelf.c (get_ppc64_symbol_other): New function. (get_symbol_other): Use it for EM_PPC64. --- bfd/ChangeLog | 17 ++++++++++++++ bfd/elf64-ppc.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 80 insertions(+), 9 deletions(-) (limited to 'bfd') diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 2c4bb31..d9551a1 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,4 +1,21 @@ 2013-10-30 Alan Modra + Ulrich Weigand + + * elf64-ppc.c (struct ppc_stub_hash_entry): Add "other". + (stub_hash_newfunc): Init new ppc_stub_hash_entry field, and one + we forgot, "plt_ent". + (ppc64_elf_add_symbol_hook): Check ELFv1 objects don't have + st_other bits only valid in ELFv2. + (ppc64_elf_merge_symbol_attribute): New function. + (ppc_type_of_stub): Add local_off param to test branch range. + (ppc_build_one_stub): Adjust destinations for ELFv2 locals. + (ppc_size_one_stub, toc_adjusting_stub_needed): Similarly. + (ppc64_elf_size_stubs): Pass local_off to ppc_type_of_stub. + Set "other" field. + (ppc64_elf_relocate_section): Adjust destination for ELFv2 local + calls. + +2013-10-30 Alan Modra * elf64-ppc.c (abiversion, set_abiversion): New functions. (ppc64_elf_get_synthetic_symtab): Handle ELFv2 objects without .opd. diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c index 0067295..1d03f84 100644 --- a/bfd/elf64-ppc.c +++ b/bfd/elf64-ppc.c @@ -118,6 +118,7 @@ static bfd_vma opd_entry_value #define elf_backend_link_output_symbol_hook ppc64_elf_output_symbol_hook #define elf_backend_special_sections ppc64_elf_special_sections #define elf_backend_post_process_headers _bfd_elf_set_osabi +#define elf_backend_merge_symbol_attribute ppc64_elf_merge_symbol_attribute /* The name of the dynamic interpreter. This is put in the .interp section. */ @@ -3746,6 +3747,9 @@ struct ppc_stub_hash_entry { /* Where this stub is being called from, or, in the case of combined stub sections, the first input section in the group. */ asection *id_sec; + + /* Symbol st_other. */ + unsigned char other; }; struct ppc_branch_hash_entry { @@ -4004,7 +4008,9 @@ stub_hash_newfunc (struct bfd_hash_entry *entry, eh->target_value = 0; eh->target_section = NULL; eh->h = NULL; + eh->plt_ent = NULL; eh->id_sec = NULL; + eh->other = 0; } return entry; @@ -4750,7 +4756,7 @@ static bfd_boolean ppc64_elf_add_symbol_hook (bfd *ibfd, struct bfd_link_info *info, Elf_Internal_Sym *isym, - const char **name ATTRIBUTE_UNUSED, + const char **name, flagword *flags ATTRIBUTE_UNUSED, asection **sec, bfd_vma *value ATTRIBUTE_UNUSED) @@ -4770,9 +4776,35 @@ ppc64_elf_add_symbol_hook (bfd *ibfd, && strcmp ((*sec)->name, ".opd") == 0) isym->st_info = ELF_ST_INFO (ELF_ST_BIND (isym->st_info), STT_FUNC); + if ((STO_PPC64_LOCAL_MASK & isym->st_other) != 0) + { + if (abiversion (ibfd) == 0) + set_abiversion (ibfd, 2); + else if (abiversion (ibfd) == 1) + { + info->callbacks->einfo (_("%P: symbol '%s' has invalid st_other" + " for ABI version 1\n"), name); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + } + return TRUE; } +/* Merge non-visibility st_other attributes: local entry point. */ + +static void +ppc64_elf_merge_symbol_attribute (struct elf_link_hash_entry *h, + const Elf_Internal_Sym *isym, + bfd_boolean definition, + bfd_boolean dynamic) +{ + if (definition && !dynamic) + h->other = ((isym->st_other & ~ELF_ST_VISIBILITY (-1)) + | ELF_ST_VISIBILITY (h->other)); +} + /* This function makes an old ABI object reference to ".bar" cause the inclusion of a new ABI object archive that defines "bar". NAME is a symbol defined in an archive. Return a symbol in the hash @@ -9796,7 +9828,8 @@ ppc_type_of_stub (asection *input_sec, const Elf_Internal_Rela *rel, struct ppc_link_hash_entry **hash, struct plt_entry **plt_ent, - bfd_vma destination) + bfd_vma destination, + unsigned long local_off) { struct ppc_link_hash_entry *h = *hash; bfd_vma location; @@ -9865,7 +9898,7 @@ ppc_type_of_stub (asection *input_sec, if (r_type != R_PPC64_REL24) max_branch_offset = 1 << 15; - if (branch_offset + max_branch_offset >= 2 * max_branch_offset) + if (branch_offset + max_branch_offset >= 2 * max_branch_offset - local_off) /* We need a stub. Figure out whether a long_branch or plt_branch is needed later. */ return ppc_stub_long_branch; @@ -10233,9 +10266,11 @@ ppc_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg) case ppc_stub_long_branch: case ppc_stub_long_branch_r2off: /* Branches are relative. This is where we are going to. */ - off = dest = (stub_entry->target_value - + stub_entry->target_section->output_offset - + stub_entry->target_section->output_section->vma); + dest = (stub_entry->target_value + + stub_entry->target_section->output_offset + + stub_entry->target_section->output_section->vma); + dest += PPC64_LOCAL_ENTRY_OFFSET (stub_entry->other); + off = dest; /* And this is where we are coming from. */ off -= (stub_entry->stub_offset @@ -10338,6 +10373,8 @@ ppc_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg) dest = (stub_entry->target_value + stub_entry->target_section->output_offset + stub_entry->target_section->output_section->vma); + if (stub_entry->stub_type != ppc_stub_plt_branch_r2off) + dest += PPC64_LOCAL_ENTRY_OFFSET (stub_entry->other); bfd_put_64 (htab->brlt->owner, dest, htab->brlt->contents + br_entry->offset); @@ -10682,6 +10719,7 @@ ppc_size_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg) /* ppc_stub_long_branch or ppc_stub_plt_branch, or their r2off variants. */ bfd_vma r2off = 0; + bfd_vma local_off = 0; off = (stub_entry->target_value + stub_entry->target_section->output_offset @@ -10710,8 +10748,10 @@ ppc_size_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg) off -= size - 4; } + local_off = PPC64_LOCAL_ENTRY_OFFSET (stub_entry->other); + /* If the branch offset if too big, use a ppc_stub_plt_branch. */ - if (off + (1 << 25) >= (bfd_vma) (1 << 26)) + if (off + (1 << 25) >= (bfd_vma) (1 << 26) - local_off) { struct ppc_branch_hash_entry *br_entry; @@ -11308,7 +11348,10 @@ toc_adjusting_stub_needed (struct bfd_link_info *info, asection *isec) need a plt_branch stub. A plt_branch stub uses r2. */ else if (dest - (isec->output_offset + isec->output_section->vma - + rel->r_offset) + (1 << 25) >= (2 << 25)) + + rel->r_offset) + (1 << 25) + >= (2u << 25) - PPC64_LOCAL_ENTRY_OFFSET (h + ? h->other + : sym->st_other)) { ret = 1; break; @@ -11761,6 +11804,7 @@ ppc64_elf_size_stubs (struct bfd_link_info *info, bfd_signed_vma group_size, asection *sym_sec, *code_sec; bfd_vma sym_value, code_value; bfd_vma destination; + unsigned long local_off; bfd_boolean ok_dest; struct ppc_link_hash_entry *hash; struct ppc_link_hash_entry *fdh; @@ -11837,12 +11881,16 @@ ppc64_elf_size_stubs (struct bfd_link_info *info, bfd_signed_vma group_size, } destination = 0; + local_off = 0; if (ok_dest) { sym_value += irela->r_addend; destination = (sym_value + sym_sec->output_offset + sym_sec->output_section->vma); + local_off = PPC64_LOCAL_ENTRY_OFFSET (hash + ? hash->elf.other + : sym->st_other); } code_sec = sym_sec; @@ -11879,7 +11927,8 @@ ppc64_elf_size_stubs (struct bfd_link_info *info, bfd_signed_vma group_size, /* Determine what (if any) linker stub is needed. */ plt_ent = NULL; stub_type = ppc_type_of_stub (section, irela, &hash, - &plt_ent, destination); + &plt_ent, destination, + local_off); if (stub_type != ppc_stub_plt_call) { @@ -11979,6 +12028,7 @@ ppc64_elf_size_stubs (struct bfd_link_info *info, bfd_signed_vma group_size, } stub_entry->h = hash; stub_entry->plt_ent = plt_ent; + stub_entry->other = hash ? hash->elf.other : sym->st_other; if (stub_entry->h != NULL) htab->stub_globals += 1; @@ -13357,6 +13407,10 @@ ppc64_elf_relocate_section (bfd *output_bfd, + input_section->output_offset + input_section->output_section->vma); + relocation += PPC64_LOCAL_ENTRY_OFFSET (fdh + ? fdh->elf.other + : sym->st_other); + if (stub_entry != NULL && (stub_entry->stub_type == ppc_stub_long_branch || stub_entry->stub_type == ppc_stub_plt_branch) -- cgit v1.1