Alfie Richards <alfie.richa...@arm.com> writes:
> Hi Richard,
>
> Is this backport okay for GCC 14 as well?
> (It applies cleanly for 14 but patch for 12 and 13 required a minor edit)
Yeah, OK for GCC 14, thanks.
Richard
>
> Alfie
>
> On 20/03/2025 14:05, Alfie Richards wrote:
>> Hi all,
>>
>> This commit applies cleanly to GCC 14 and fixes PR119372.
>>
>> Bootstrapped and regtested on aarch64-linux-gnu.
>>
>> Okay for gcc 14 backport?
>>
>> Alfie Richards
>>
>> On 08/10/2024 16:46, Richard Sandiford wrote:
>>> Andrew Carlotti <andrew.carlo...@arm.com> writes:
>>>> gcc/ChangeLog:
>>>>
>>>> * config/aarch64/aarch64.cc
>>>> (aarch64_expand_epilogue): Use TARGET_PAUTH.
>>>> * config/aarch64/aarch64.md: Update comment.
>>>>
>>>>
>>>> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/
>>>> aarch64.cc
>>>> index
>>>> e7bb3278a27eca44c46afd26069d608218198a54..cf1107127fd5d9e12ad42441528666bf6b733f73
>>>> 100644
>>>> --- a/gcc/config/aarch64/aarch64.cc
>>>> +++ b/gcc/config/aarch64/aarch64.cc
>>>> @@ -10042,12 +10042,12 @@ aarch64_expand_epilogue (rtx_call_insn
>>>> *sibcall)
>>>> 1) Sibcalls don't return in a normal way, so if we're about to
>>>> call one
>>>> we must authenticate.
>>>> - 2) The RETAA instruction is not available before ARMv8.3-A, so
>>>> if we are
>>>> - generating code for !TARGET_ARMV8_3 we can't use it and must
>>>> + 2) The RETAA instruction is not available without FEAT_PAuth, so
>>>> if we
>>>> + are generating code for !TARGET_PAUTH we can't use it and must
>>>> explicitly authenticate.
>>>> */
>>>> if (aarch64_return_address_signing_enabled ()
>>>> - && (sibcall || !TARGET_ARMV8_3))
>>>> + && (sibcall || !TARGET_PAUTH))
>>>> {
>>>> switch (aarch64_ra_sign_key)
>>>> {
>>>> diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/
>>>> aarch64.md
>>>> index
>>>> c54b29cd64b9e0dc6c6d12735049386ccedc5408..0940a84f9295ee2bc07282b150095fdb5af11a4d
>>>> 100644
>>>> --- a/gcc/config/aarch64/aarch64.md
>>>> +++ b/gcc/config/aarch64/aarch64.md
>>>> @@ -7672,10 +7672,10 @@
>>>> )
>>>> ;; Pointer authentication patterns are always provided. In
>>>> architecture
>>>> -;; revisions prior to ARMv8.3-A these HINT instructions operate as
>>>> NOPs.
>>>> +;; revisions prior to FEAT_PAuth these HINT instructions operate as
>>>> NOPs.
>>>
>>> I suppose this should be something like "On targets that don't implement
>>> FEAT_PAuth". OK with that change, thanks.
>>>
>>> Richard
>>>
>>>> ;; This lets the user write portable software which authenticates
>>>> pointers
>>>> -;; when run on something which implements ARMv8.3-A, and which runs
>>>> -;; correctly, but does not authenticate pointers, where ARMv8.3-A is
>>>> not
>>>> +;; when run on something which implements FEAT_PAuth, and which runs
>>>> +;; correctly, but does not authenticate pointers, where FEAT_PAuth
>>>> is not
>>>> ;; implemented.
>>>> ;; Signing/Authenticating R30 using SP as the salt.
>>>
>>
