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-rw-r--r--bfd/ChangeLog9
-rw-r--r--bfd/elf64-ppc.c111
-rw-r--r--gold/ChangeLog5
-rw-r--r--gold/powerpc.cc11
4 files changed, 89 insertions, 47 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 71d6148..7511c6c 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,14 @@
2013-07-03 Alan Modra <amodra@gmail.com>
+ * elf64-ppc.c (struct ppc_stub_hash_entry): Delete "addend".
+ (ppc64_elf_size_stubs): Don't set "addend".
+ (ppc64_elf_relocate_section): Don't allow calls via
+ toc-adjusting stubs without a following nop even in an
+ executable, except for self-calls and both libc_start_main
+ and .libc_start_main.
+
+2013-07-03 Alan Modra <amodra@gmail.com>
+
* elf64-ppc.c (ppc64_elf_func_desc_adjust): Hide ".TOC.".
2013-07-02 Tristan Gingold <gingold@adacore.com>
diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 5a4bcfd..21d8263 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -3618,9 +3618,6 @@ struct ppc_stub_hash_entry {
struct ppc_link_hash_entry *h;
struct plt_entry *plt_ent;
- /* And the reloc addend that this was derived from. */
- bfd_vma addend;
-
/* 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;
@@ -11752,7 +11749,6 @@ 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->addend = irela->r_addend;
if (stub_entry->h != NULL)
htab->stub_globals += 1;
@@ -13015,60 +13011,89 @@ ppc64_elf_relocate_section (bfd *output_bfd,
{
bfd_boolean can_plt_call = FALSE;
+ /* All of these stubs will modify r2, so there must be a
+ branch and link followed by a nop. The nop is
+ replaced by an insn to restore r2. */
if (rel->r_offset + 8 <= input_section->size)
{
- unsigned long nop;
- nop = bfd_get_32 (input_bfd, contents + rel->r_offset + 4);
- if (nop == NOP
- || nop == CROR_151515 || nop == CROR_313131)
+ unsigned long br;
+
+ br = bfd_get_32 (input_bfd,
+ contents + rel->r_offset);
+ if ((br & 1) != 0)
{
- if (h != NULL
- && (h == htab->tls_get_addr_fd
- || h == htab->tls_get_addr)
- && !htab->no_tls_get_addr_opt)
+ unsigned long nop;
+
+ nop = bfd_get_32 (input_bfd,
+ contents + rel->r_offset + 4);
+ if (nop == NOP
+ || nop == CROR_151515 || nop == CROR_313131)
{
- /* Special stub used, leave nop alone. */
+ if (h != NULL
+ && (h == htab->tls_get_addr_fd
+ || h == htab->tls_get_addr)
+ && !htab->no_tls_get_addr_opt)
+ {
+ /* Special stub used, leave nop alone. */
+ }
+ else
+ bfd_put_32 (input_bfd, LD_R2_40R1,
+ contents + rel->r_offset + 4);
+ can_plt_call = TRUE;
}
- else
- bfd_put_32 (input_bfd, LD_R2_40R1,
- contents + rel->r_offset + 4);
- can_plt_call = TRUE;
}
}
- if (!can_plt_call)
+ if (!can_plt_call && h != NULL)
{
- if (stub_entry->stub_type == ppc_stub_plt_call
- || stub_entry->stub_type == ppc_stub_plt_call_r2save)
- {
- /* If this is a plain branch rather than a branch
- and link, don't require a nop. However, don't
- allow tail calls in a shared library as they
- will result in r2 being corrupted. */
- unsigned long br;
- br = bfd_get_32 (input_bfd, contents + rel->r_offset);
- if (info->executable && (br & 1) == 0)
- can_plt_call = TRUE;
- else
- stub_entry = NULL;
- }
- else if (h != NULL
- && strcmp (h->elf.root.root.string,
- ".__libc_start_main") == 0)
+ const char *name = h->elf.root.root.string;
+
+ if (*name == '.')
+ ++name;
+
+ if (strncmp (name, "__libc_start_main", 17) == 0
+ && (name[17] == 0 || name[17] == '@'))
{
- /* Allow crt1 branch to go via a toc adjusting stub. */
+ /* Allow crt1 branch to go via a toc adjusting
+ stub. Other calls that never return could do
+ the same, if we could detect such. */
can_plt_call = TRUE;
}
- else
+ }
+
+ if (!can_plt_call)
+ {
+ /* g++ as of 20130507 emits self-calls without a
+ following nop. This is arguably wrong since we
+ have conflicting information. On the one hand a
+ global symbol and on the other a local call
+ sequence, but don't error for this special case.
+ It isn't possible to cheaply verify we have
+ exactly such a call. Allow all calls to the same
+ section. */
+ asection *code_sec = sec;
+
+ if (get_opd_info (sec) != NULL)
{
- info->callbacks->einfo
- (_("%P: %H: call to `%T' lacks nop, can't restore toc; "
- "recompile with -fPIC"),
- input_bfd, input_section, rel->r_offset, sym_name);
+ bfd_vma off = (relocation + addend
+ - sec->output_section->vma
+ - sec->output_offset);
- bfd_set_error (bfd_error_bad_value);
- ret = FALSE;
+ opd_entry_value (sec, off, &code_sec, NULL, FALSE);
}
+ if (code_sec == input_section)
+ can_plt_call = TRUE;
+ }
+
+ if (!can_plt_call)
+ {
+ info->callbacks->einfo
+ (_("%P: %H: call to `%T' lacks nop, can't restore toc; "
+ "recompile with -fPIC"),
+ input_bfd, input_section, rel->r_offset, sym_name);
+
+ bfd_set_error (bfd_error_bad_value);
+ ret = FALSE;
}
if (can_plt_call
diff --git a/gold/ChangeLog b/gold/ChangeLog
index 3ca1cf7..3373715 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,8 @@
+2013-07-03 Alan Modra <amodra@gmail.com>
+
+ * powerpc.cc (Target_powerpc::Relocate::relocate): Update self-call
+ comment.
+
2013-07-01 Cary Coutant <ccoutant@google.com>
* dwarf_reader.cc (Dwarf_ranges_table::read_ranges_table): Save
diff --git a/gold/powerpc.cc b/gold/powerpc.cc
index 17849ee..0653ea7 100644
--- a/gold/powerpc.cc
+++ b/gold/powerpc.cc
@@ -6346,10 +6346,13 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
}
if (!can_plt_call)
{
- // This is not an error in one special case: A self
- // call. It isn't possible to cheaply verify we have
- // such a call so just check for a call to the same
- // section.
+ // g++ as of 20130507 emits self-calls without a
+ // following nop. This is arguably wrong since we have
+ // conflicting information. On the one hand a global
+ // symbol and on the other a local call sequence, but
+ // don't error for this special case.
+ // It isn't possible to cheaply verify we have exactly
+ // such a call. Allow all calls to the same section.
bool ok = false;
Address code = value;
if (gsym->source() == Symbol::FROM_OBJECT