[PATCH] D145221: [X86] Prefer `vpternlog` instead of `blendv` for `vselect` on masks.

Fri Mar 3 02:46:18 PST 2023

RKSimon added inline comments.

================
Comment at: llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:1044
+      if (Subtarget->hasVLX() && Subtarget->hasAVX512() &&
+          N->getOperand(0)->getOpcode() == X86ISD::PCMPGT) {
+        R = CurDAG->getNode(X86ISD::VPTERNLOG, SDLoc(N), N->getValueType(0),
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craig.topper wrote:
> Why is the PCMPGT check needed?
Wouldn't a numsignbits check be better than PCMPGT?

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D145221/new/

https://reviews.llvm.org/D145221