[PATCH] D142410: [AArch64] ARMv8.5-A implies both FEAT_SB and FEAT_SSBS

[Philipp Tomsich via Phabricator via llvm-commits]

philipp.tomsich abandoned this revision.
philipp.tomsich added a comment.

I just saw that the last response was "unsubmitted".

Submitting and abandoning this revision (based on the discussion and the previously unsubmitted comment from my end).



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Comment at: llvm/include/llvm/TargetParser/AArch64TargetParser.h:311
 inline constexpr ArchInfo ARMV8_4A  = { VersionTuple{8, 4}, AProfile, "armv8.4-a", "+v8.4a", (ARMV8_3A.DefaultExts | AArch64::AEK_DOTPROD)};
-inline constexpr ArchInfo ARMV8_5A  = { VersionTuple{8, 5}, AProfile, "armv8.5-a", "+v8.5a", (ARMV8_4A.DefaultExts)};
+inline constexpr ArchInfo ARMV8_5A  = { VersionTuple{8, 5}, AProfile, "armv8.5-a", "+v8.5a", (ARMV8_4A.DefaultExts | AArch64::AEK_SB | AArch64::AEK_SSBS )};
 constexpr unsigned BaseNoCrypto = ARMV8_5A.DefaultExts ^ AArch64::AEK_CRYPTO; // 8.6 onwards has no AEK_CRYPTO
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lenary wrote:
> According to the A-profile Arm ARM (version I.a):
> - FEAT_SB is mandatory from v8.5 onwards, so thank you for correcting this oversight.
> - There is no language about the same for FEAT_SSBS/FEAT_SSBS2. It was added to v8.0a by v8.5a, but it doesn't seem to have been made mandatory in v8.5a, as far as I can see. There is no language in section A2 (Architectural Extensions), or in the description of the `ID_AA64PFR1_EL1.SSBS` register about being mandatory from certain versions (other fields in this register do have this language).
I have now picked up I.a after I had previously referenced G.a.

Features added to earlier extensions (For ARMv8.5) lists FEAT_SBSS.
However, the Text under FEAT_SBSS/FEAT_SSBS2 no longer has the "This feature is OPTIONAL in Armv8.0 implementations and mandatory in Armv8.5 implementations." that was present in version G.a of the spec.

So it looks as if this was made optional again somewhere between G.a and I.a?





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