[X86][LLVM][TD] Arranging Atom family in an inheritance ratio
Needs ReviewPublic

Authored by m_zuckerman on Thu, Jul 13, 6:48 AM.

Details

Summary

X86.td file contains number of features that can be arrange in more general pattern . We can combine features that include in number of atom into single processor and create a inheritance ratio between them all.

Diff Detail

m_zuckerman created this revision.Thu, Jul 13, 6:48 AM
craig.topper added inline comments.Sun, Jul 16, 11:11 PM
lib/Target/X86/X86.td
419–420

This looks to be adding RDRAND to SLM. Whether that's correct or not, that's a functional change which should not be part of this patch.

428

Should SSSE3 be part of AtomValues instead? The rest of these are uarch details, but that one is a real feature and should be with the other features.

m_zuckerman added inline comments.Mon, Jul 17, 5:07 AM
lib/Target/X86/X86.td
419–420

hi.
First, this feature is part of SLM.
Secondly , why don't you want it as part of the patch ?

428

Higher features hint for lower features. In this case feature SSSE3 is part of the SSE42 so i didn't want to create a duplication.

craig.topper added inline comments.Mon, Jul 17, 7:03 AM
lib/Target/X86/X86.td
419–420

I agree that it's part of SLM and that it should be fixed. But this patch should be treated as a refactor that doesn't change behavior. Especially since your description makes no mention of this change. And clang needs to be updated too. So submit a separate pre or post patch for the SLM rdrand change.