[PATCH] D28447: [X86][AVX512BW] Vectorize v64i8 vector shifts

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: lib/Target/X86/X86ISelLowering.cpp:21544
     auto SignBitSelect = [&](MVT SelVT, SDValue Sel, SDValue V0, SDValue V1) {
-      // On SSE41 targets we make use of the fact that VSELECT lowers
-      // to PBLENDVB which selects bytes based just on the sign bit.
-      if (Subtarget.hasSSE41()) {
+      if (Subtarget.hasBWI() && VT.is512BitVector()) {
+        // On AVX512BW targets we test for the sign bit by comparing to
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Isn't hasBWI() already implied by the earlier if? Can a 512BitVector get here without BWI?


Repository:
  rL LLVM

https://reviews.llvm.org/D28447