[llvm] 94a4a2c - [X86][SSE] combineX86ShuffleChain - use resolveZeroablesFromTargetShuffle helper. NFCI.

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2019-10-30T18:30:01Z
New Revision: 94a4a2c97f8187f4fb73f8e8460d4cb11feb470c

URL: https://github.com/llvm/llvm-project/commit/94a4a2c97f8187f4fb73f8e8460d4cb11feb470c
DIFF: https://github.com/llvm/llvm-project/commit/94a4a2c97f8187f4fb73f8e8460d4cb11feb470c.diff

LOG: [X86][SSE] combineX86ShuffleChain - use resolveZeroablesFromTargetShuffle helper. NFCI.

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86ISelLowering.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index ccb8e8aa76b3..d9e38b18d86c 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -32414,10 +32414,9 @@ static SDValue combineX86ShuffleChain(ArrayRef<SDValue> Inputs, SDValue Root,
                         (!MaskVT.is256BitVector() || Subtarget.hasAVX2());
 
   // Determine zeroable mask elements.
-  APInt Zeroable(NumMaskElts, 0);
-  for (unsigned i = 0; i != NumMaskElts; ++i)
-    if (isUndefOrZero(Mask[i]))
-      Zeroable.setBit(i);
+  APInt KnownUndef, KnownZero;
+  resolveZeroablesFromTargetShuffle(Mask, KnownUndef, KnownZero);
+  APInt Zeroable = KnownUndef | KnownZero;
 
   if (UnaryShuffle) {
     // If we are shuffling a X86ISD::VZEXT_LOAD then we can use the load