XinWang10 marked an inline comment as done. XinWang10 added inline comments.
================ Comment at: llvm/lib/Target/X86/X86.td:437 + : SubtargetFeature<"prefer-no-gather", "PreferGather", "false", + "Indicates if gather prefer to be disabled">; +def FeaturePreferNoScatter ---------------- XinWang10 wrote: > pengfei wrote: > > XinWang10 wrote: > > > skan wrote: > > > > Does "Prefer no gather instructions" sound better? > > > > > > > > I think these two should be put under "X86 Subtarget Tuning features"? > > > I think the two options are to mitigate security issues. Could refer to > > > link in summary. > > It depends on if the micro code was applied. We should assume user care of > > this option should have applied the micro code. So it's more like a > > performance turning rather than mitigation. And you cannot disable all > > gather/scatter instructions with these options. > Micro code applied? You mean we should keep eye on the byte code generated. > And what's the essential difference between performance turning and > mitigation? Do mitigation for no-gather means we could not emit gather > whenever but performance turning could exist some gather considering the > performance? > Second, I think the intention for this option is to mitigate the security > issue but not tune the performance. Talked offline and agreed to move to performance tuning. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D157680/new/ https://reviews.llvm.org/D157680 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
