[PATCH] D33311: [X86] Match bitcast of vsetcc to pmovmsk

[Zvi Rackover via Phabricator via llvm-commits]

zvi added inline comments.


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Comment at: lib/Target/X86/X86ISelLowering.cpp:29020
+  // vxi1 types.
+  if (!LegalTypes && N0.getOpcode() == ISD::SETCC)
+    if (SDValue V = combineBitcastOfSetCC(DAG, SDLoc(N), VT, N0, Subtarget))
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delena wrote:
> zvi wrote:
> > delena wrote:
> > > Can you use if (VT.isInteger() && DAG.ComputeNumSignBits(N) == EltBits) ?
> > i didn't understand the question. Can you please explain this point?
> ISD::SETCC is a private case when you know about all-ones or all-zeroes.  DAG.ComputeNumSignBits(N) == EltBits is more general.
That's a good idea. Do you have an example of such a case?



https://reviews.llvm.org/D33311