[PATCH] D130339: [CodeGen] Generate efficient assembly for freeze(poison) version of `mm*_cast*` intel intrinsics

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/Target/X86/X86InstrVecCompiler.td:74
+
+  def : Pat<(VT (insert_subvector (freeze (VT undef)), subRC:$src,
+                                  (iPTR 0))),
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RKSimon wrote:
> Could we add a generic pattern for "undef_or_freeze_undef" that we could use here as I imagine a lot more places are going to need something like this and we should try to avoid duplication if we can?
With the change I mentioned in TargetSelectionDAG.td you shouldn't need to mention `VT` near freeze or undef. The one at the start of the pattern will be enough.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130339/new/

https://reviews.llvm.org/D130339