[X86] Cleanup uses of computeKnownBits by using MaskedValueIsZero helper instead...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314652 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 616519941fcb22121629ff35081b3d9db32f9224..6f0b81224348a7919e6b9272be432f1081bd3c49 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -5946,12 +5946,9 @@ static bool getFauxShuffleMask(SDValue N, SmallVectorImpl<int> &Mask,
           DAG.ComputeNumSignBits(N1) <= NumBitsPerElt)
         return false;
     } else {
-      KnownBits Known0, Known1;
-      DAG.computeKnownBits(N0, Known0);
-      if (Known0.countMinLeadingZeros() < NumBitsPerElt)
-        return false;
-      DAG.computeKnownBits(N1, Known1);
-      if (Known1.countMinLeadingZeros() < NumBitsPerElt)
+      APInt ZeroMask = APInt::getHighBitsSet(2 * NumBitsPerElt, NumBitsPerElt);
+      if (!DAG.MaskedValueIsZero(N0, ZeroMask) ||
+          !DAG.MaskedValueIsZero(N1, ZeroMask))
         return false;
     }