[PATCH] D29623: [ARM] Replace HasT2ExtractPack with HasDSP

[Oliver Stannard via Phabricator via llvm-commits]

olista01 requested changes to this revision.
olista01 added a comment.
This revision now requires changes to proceed.

I've had a look through the architecture manuals, and I think we do need two different features here.

For example:

- The QADD instruction (currently predicated on FeatureDSP) was introduced by the DSP extension to ARMv5 (aka ARMv5TE)
- The SXTAB instruction (currently predicated on FeatureT2XtPk) was introduced by ARMv6 (but is also optionally available as part of the DSP extension to ARMv7-M)

Therefore, I think we need to keep two separate features. However, we may be able to make FeatureT2XtPk depend on FeatureDSP, as I haven't been able to find any architecture where SXTAB is available without QADD.


https://reviews.llvm.org/D29623