X86-64: Correct CFA in _dl_runtime_resolve
Commit Message
When stack is re-aligned in _dl_runtime_resolve, there is no need to
adjust CFA when allocating register save area on stack.
Tested on x86-64. OK for master?
H.J.
---
* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Don't
adjust CFA when allocating register save area on re-aligned
stack.
---
sysdeps/x86_64/dl-trampoline.h | 2 ++
1 file changed, 2 insertions(+)
Comments
On Fri, Aug 19, 2016 at 1:30 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> When stack is re-aligned in _dl_runtime_resolve, there is no need to
> adjust CFA when allocating register save area on stack.
>
> Tested on x86-64. OK for master?
>
>
> H.J.
> ---
> * sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Don't
> adjust CFA when allocating register save area on re-aligned
> stack.
> ---
> sysdeps/x86_64/dl-trampoline.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h
> index b90836a..8161f96 100644
> --- a/sysdeps/x86_64/dl-trampoline.h
> +++ b/sysdeps/x86_64/dl-trampoline.h
> @@ -69,7 +69,9 @@ _dl_runtime_resolve:
> and $-VEC_SIZE, %RSP_LP
> #endif
> sub $REGISTER_SAVE_AREA, %RSP_LP
> +#if !DL_RUNTIME_RESOLVE_REALIGN_STACK
> cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
> +#endif
> # Preserve registers otherwise clobbered.
> movq %rax, REGISTER_SAVE_RAX(%rsp)
> movq %rcx, REGISTER_SAVE_RCX(%rsp)
> --
> 2.7.4
>
I am checking it in.
On Fri, Aug 26, 2016 at 8:53 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Fri, Aug 19, 2016 at 1:30 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
>> When stack is re-aligned in _dl_runtime_resolve, there is no need to
>> adjust CFA when allocating register save area on stack.
>>
>> Tested on x86-64. OK for master?
>>
>>
>> H.J.
>> ---
>> * sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Don't
>> adjust CFA when allocating register save area on re-aligned
>> stack.
>> ---
>> sysdeps/x86_64/dl-trampoline.h | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h
>> index b90836a..8161f96 100644
>> --- a/sysdeps/x86_64/dl-trampoline.h
>> +++ b/sysdeps/x86_64/dl-trampoline.h
>> @@ -69,7 +69,9 @@ _dl_runtime_resolve:
>> and $-VEC_SIZE, %RSP_LP
>> #endif
>> sub $REGISTER_SAVE_AREA, %RSP_LP
>> +#if !DL_RUNTIME_RESOLVE_REALIGN_STACK
>> cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
>> +#endif
>> # Preserve registers otherwise clobbered.
>> movq %rax, REGISTER_SAVE_RAX(%rsp)
>> movq %rcx, REGISTER_SAVE_RCX(%rsp)
>> --
>> 2.7.4
>>
>
> I am checking it in.
>
I am backporting it to 2.24 and 2.23 branches.
@@ -69,7 +69,9 @@ _dl_runtime_resolve:
and $-VEC_SIZE, %RSP_LP
#endif
sub $REGISTER_SAVE_AREA, %RSP_LP
+#if !DL_RUNTIME_RESOLVE_REALIGN_STACK
cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
+#endif
# Preserve registers otherwise clobbered.
movq %rax, REGISTER_SAVE_RAX(%rsp)
movq %rcx, REGISTER_SAVE_RCX(%rsp)