commit ee67d69a3ff0eed25d98c5e97ed6c3ede8069edc
Author: Alan Modra <amodra@gmail.com>
Date: Tue Oct 29 15:06:09 2013 +1030
Add .abiversion related support for ELFv2
Defines bits in ELF e_flags to differentiate ELFv2 objects from ELFv2,
adds .abiversion directive to explicitly choose the ABI, and code to
check and automatically select ABI.
include/elf/
* ppc64.h (EF_PPC64_ABI): Define.
bfd/
* elf64-ppc.c (abiversion, set_abiversion): New functions.
(ppc64_elf_get_synthetic_symtab): Handle ELFv2 objects without .opd.
(struct ppc_link_hash_table): Add opd_abi.
(ppc64_elf_check_relocs): Check no .opd with ELFv2.
(ppc64_elf_merge_private_bfd_data): New function.
(ppc64_elf_print_private_bfd_data): New function.
(ppc64_elf_tls_setup): Set htab->opd_abi.
(ppc64_elf_size_dynamic_sections): Don't emit OPD related dynamic
tags for ELFv2.
(ppc_build_one_stub): Use R_PPC64_IRELATIVE for ELFv2 ifunc.
(ppc64_elf_finish_dynamic_symbol): Likewise
binutils/
* readelf.c (get_machine_flags): Display ABI version for EM_PPC64.
gas/
* config/tc-ppc.c: Include elf/ppc64.h.
(ppc_abiversion): New variable.
(md_pseudo_table): Add .abiversion.
(ppc_elf_abiversion, ppc_elf_end): New functions.
* config/tc-ppc.h (md_end): Define.
Index: gdb-7.6.1/bfd/elf64-ppc.c
===================================================================
--- gdb-7.6.1.orig/bfd/elf64-ppc.c
+++ gdb-7.6.1/bfd/elf64-ppc.c
@@ -81,7 +81,8 @@ static bfd_vma opd_entry_value
#define bfd_elf64_mkobject ppc64_elf_mkobject
#define bfd_elf64_bfd_reloc_type_lookup ppc64_elf_reloc_type_lookup
#define bfd_elf64_bfd_reloc_name_lookup ppc64_elf_reloc_name_lookup
-#define bfd_elf64_bfd_merge_private_bfd_data _bfd_generic_verify_endian_match
+#define bfd_elf64_bfd_merge_private_bfd_data ppc64_elf_merge_private_bfd_data
+#define bfd_elf64_bfd_print_private_bfd_data ppc64_elf_print_private_bfd_data
#define bfd_elf64_new_section_hook ppc64_elf_new_section_hook
#define bfd_elf64_bfd_link_hash_table_create ppc64_elf_link_hash_table_create
#define bfd_elf64_bfd_link_hash_table_free ppc64_elf_link_hash_table_free
@@ -2836,6 +2837,19 @@ get_opd_info (asection * sec)
return &ppc64_elf_section_data (sec)->u.opd;
return NULL;
}
+
+static inline int
+abiversion (bfd *abfd)
+{
+ return elf_elfheader (abfd)->e_flags & EF_PPC64_ABI;
+}
+
+static inline void
+set_abiversion (bfd *abfd, int ver)
+{
+ elf_elfheader (abfd)->e_flags &= ~EF_PPC64_ABI;
+ elf_elfheader (abfd)->e_flags |= ver & EF_PPC64_ABI;
+}
/* Parameters for the qsort hook. */
static bfd_boolean synthetic_relocatable;
@@ -2982,15 +2996,19 @@ ppc64_elf_get_synthetic_symtab (bfd *abf
long count;
char *names;
long symcount, codesecsym, codesecsymend, secsymend, opdsymend;
- asection *opd;
+ asection *opd = NULL;
bfd_boolean relocatable = (abfd->flags & (EXEC_P | DYNAMIC)) == 0;
asymbol **syms;
+ int abi = abiversion (abfd);
*ret = NULL;
- opd = bfd_get_section_by_name (abfd, ".opd");
- if (opd == NULL)
- return 0;
+ if (abi < 2)
+ {
+ opd = bfd_get_section_by_name (abfd, ".opd");
+ if (opd == NULL && abi == 1)
+ return 0;
+ }
symcount = static_count;
if (!relocatable)
@@ -3159,20 +3177,18 @@ ppc64_elf_get_synthetic_symtab (bfd *abf
else
{
bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);
- bfd_byte *contents;
+ bfd_byte *contents = NULL;
size_t size;
long plt_count = 0;
bfd_vma glink_vma = 0, resolv_vma = 0;
asection *dynamic, *glink = NULL, *relplt = NULL;
arelent *p;
- if (!bfd_malloc_and_get_section (abfd, opd, &contents))
+ if (opd != NULL && !bfd_malloc_and_get_section (abfd, opd, &contents))
{
+ free_contents_and_exit:
if (contents)
- {
- free_contents_and_exit:
- free (contents);
- }
+ free (contents);
count = -1;
goto done;
}
@@ -3772,6 +3788,9 @@ struct ppc_link_hash_table
/* Alignment of PLT call stubs. */
unsigned int plt_stub_align:4;
+ /* Set if we're linking code with function descriptors. */
+ unsigned int opd_abi:1;
+
/* Set if PLT call stubs should load r11. */
unsigned int plt_static_chain:1;
@@ -4959,6 +4978,15 @@ ppc64_elf_check_relocs (bfd *abfd, struc
information about the associated function section. */
bfd_size_type amt;
+ if (abiversion (abfd) == 0)
+ set_abiversion (abfd, 1);
+ else if (abiversion (abfd) == 2)
+ {
+ info->callbacks->einfo (_("%P: .opd not allowed in ABI version %d\n"),
+ abiversion (abfd));
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
amt = sec->size * sizeof (*opd_sym_map) / 8;
opd_sym_map = bfd_zalloc (abfd, amt);
if (opd_sym_map == NULL)
@@ -5518,6 +5546,78 @@ ppc64_elf_check_relocs (bfd *abfd, struc
return TRUE;
}
+/* Merge backend specific data from an object file to the output
+ object file when linking. */
+
+static bfd_boolean
+ppc64_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
+{
+ unsigned long iflags, oflags;
+
+ if ((ibfd->flags & BFD_LINKER_CREATED) != 0)
+ return TRUE;
+
+ if (!is_ppc64_elf (ibfd) || !is_ppc64_elf (obfd))
+ return TRUE;
+
+ if (!_bfd_generic_verify_endian_match (ibfd, obfd))
+ return FALSE;
+
+ iflags = elf_elfheader (ibfd)->e_flags;
+ oflags = elf_elfheader (obfd)->e_flags;
+
+ if (!elf_flags_init (obfd) || oflags == 0)
+ {
+ elf_flags_init (obfd) = TRUE;
+ elf_elfheader (obfd)->e_flags = iflags;
+ }
+ else if (iflags == oflags || iflags == 0)
+ ;
+ else if (iflags & ~EF_PPC64_ABI)
+ {
+ (*_bfd_error_handler)
+ (_("%B uses unknown e_flags 0x%lx"), ibfd, iflags);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+ else
+ {
+ (*_bfd_error_handler)
+ (_("%B: ABI version %ld is not compatible with ABI version %ld output"),
+ ibfd, iflags, oflags);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+
+ /* Merge Tag_compatibility attributes and any common GNU ones. */
+ _bfd_elf_merge_object_attributes (ibfd, obfd);
+
+ return TRUE;
+}
+
+static bfd_boolean
+ppc64_elf_print_private_bfd_data (bfd *abfd, void *ptr)
+{
+ /* Print normal ELF private data. */
+ _bfd_elf_print_private_bfd_data (abfd, ptr);
+
+ if (elf_elfheader (abfd)->e_flags != 0)
+ {
+ FILE *file = ptr;
+
+ /* xgettext:c-format */
+ fprintf (file, _("private flags = 0x%lx:"),
+ elf_elfheader (abfd)->e_flags);
+
+ if ((elf_elfheader (abfd)->e_flags & EF_PPC64_ABI) != 0)
+ fprintf (file, _(" [abiv%ld]"),
+ elf_elfheader (abfd)->e_flags & EF_PPC64_ABI);
+ fputc ('\n', file);
+ }
+
+ return TRUE;
+}
+
/* OFFSET in OPD_SEC specifies a function descriptor. Return the address
of the code entry point, and its section. */
@@ -7504,6 +7604,9 @@ ppc64_elf_tls_setup (struct bfd_link_inf
if (htab == NULL)
return NULL;
+ if (abiversion (info->output_bfd) == 1)
+ htab->opd_abi = 1;
+
if (*no_multi_toc)
htab->do_multi_toc = 0;
else if (!htab->do_multi_toc)
@@ -9127,7 +9230,7 @@ readonly_dynrelocs (struct elf_link_hash
/* Set the sizes of the dynamic sections. */
static bfd_boolean
-ppc64_elf_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
+ppc64_elf_size_dynamic_sections (bfd *output_bfd,
struct bfd_link_info *info)
{
struct ppc_link_hash_table *htab;
@@ -9439,7 +9542,7 @@ ppc64_elf_size_dynamic_sections (bfd *ou
return FALSE;
}
- if (NO_OPD_RELOCS)
+ if (NO_OPD_RELOCS && abiversion (output_bfd) <= 1)
{
if (!add_dynamic_entry (DT_PPC64_OPD, 0)
|| !add_dynamic_entry (DT_PPC64_OPDSZ, 0))
@@ -10202,7 +10305,10 @@ ppc_build_one_stub (struct bfd_hash_entr
bfd_byte *rl;
rela.r_offset = dest;
- rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);
+ if (htab->opd_abi)
+ rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);
+ else
+ rela.r_info = ELF64_R_INFO (0, R_PPC64_IRELATIVE);
rela.r_addend = (stub_entry->target_value
+ stub_entry->target_section->output_offset
+ stub_entry->target_section->output_section->vma);
@@ -14012,7 +14118,10 @@ ppc64_elf_finish_dynamic_symbol (bfd *ou
rela.r_offset = (htab->iplt->output_section->vma
+ htab->iplt->output_offset
+ ent->plt.offset);
- rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);
+ if (htab->opd_abi)
+ rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);
+ else
+ rela.r_info = ELF64_R_INFO (0, R_PPC64_IRELATIVE);
rela.r_addend = (h->root.u.def.value
+ h->root.u.def.section->output_offset
+ h->root.u.def.section->output_section->vma
--- a/include/elf/ppc64.h
+++ b/include/elf/ppc64.h
@@ -173,6 +173,13 @@ END_RELOC_NUMBERS (R_PPC64_max)
(((R) >= R_PPC64_TLS && (R) <= R_PPC64_DTPREL16_HIGHESTA) \
|| ((R) >= R_PPC64_TPREL16_HIGH && (R) <= R_PPC64_DTPREL16_HIGHA))
+
+/* e_flags bits specifying ABI.
+ 1 for original function descriptor using ABI,
+ 2 for revised ABI without function descriptors,
+ 0 for unspecified or not using any features affected by the differences. */
+#define EF_PPC64_ABI 3
+
/* Specify the start of the .glink section. */
#define DT_PPC64_GLINK DT_LOPROC