[PATCH] D130830: Don't widen shuffle element with AVX512

[LuoYuanke via Phabricator via llvm-commits]

LuoYuanke added inline comments.


================
Comment at: llvm/lib/Target/X86/X86ISelLowering.cpp:16860
+    //                             undef:v16i16
+    if (CrossLaneMask == Mask || InLaneMask == Mask)
+      return SDValue();
----------------
If `CrossLaneMask == Mask`, `InLaneMask` must be identity mask. However I'm not sure if `InLaneMask == Mask` `CrossLaneMask`  must be identity mask.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130830/new/

https://reviews.llvm.org/D130830