[PATCH] D27692: [x86] use a single shufps when it can save instructions
Zia Ansari via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Tue Dec 13 10:10:31 PST 2016
zansari added a comment.
Thanks for the link, Sanjay. Yes, I was just about to comment on this in the other review as i just got confirmation.. The info in that link is right. The h/w shufflers cross both domains after IVB, therefore, not suffering the bypass penalty when switching through such instructions (perm/shuf/unpack...).
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