[llvm] 676a03d - [X86] matchBinaryShuffle - limit SHUFFLE(X,Y) -> OR(X,Y) cases to where X + Y are the same width as the result

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2022-07-23T16:56:45+01:00
New Revision: 676a03d8a5e325d8a3f92c1fb37ab0a8ae78b6e1

URL: https://github.com/llvm/llvm-project/commit/676a03d8a5e325d8a3f92c1fb37ab0a8ae78b6e1
DIFF: https://github.com/llvm/llvm-project/commit/676a03d8a5e325d8a3f92c1fb37ab0a8ae78b6e1.diff

LOG: [X86] matchBinaryShuffle - limit SHUFFLE(X,Y) -> OR(X,Y) cases to where X + Y are the same width as the result

Minor bit of prep work toward not unnecessarily widening shuffle operands in combineX86ShufflesRecursively, instead only widening in combineX86ShuffleChain if we actual find a match - see Issue #45319

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 7805493c86fc7..3caafbe1816df 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -37421,6 +37421,7 @@ static bool matchBinaryShuffle(MVT MaskVT, ArrayRef<int> Mask,
                                bool IsUnary) {
   unsigned NumMaskElts = Mask.size();
   unsigned EltSizeInBits = MaskVT.getScalarSizeInBits();
+  unsigned SizeInBits = MaskVT.getSizeInBits();
 
   if (MaskVT.is128BitVector()) {
     if (isTargetShuffleEquivalent(MaskVT, Mask, {0, 0}, DAG) &&
@@ -37488,7 +37489,10 @@ static bool matchBinaryShuffle(MVT MaskVT, ArrayRef<int> Mask,
 
   // Attempt to match against a OR if we're performing a blend shuffle and the
   // non-blended source element is zero in each case.
-  if ((EltSizeInBits % V1.getScalarValueSizeInBits()) == 0 &&
+  // TODO: Handle cases where V1/V2 sizes doesn't match SizeInBits.
+  if (SizeInBits == V1.getValueSizeInBits() &&
+      SizeInBits == V2.getValueSizeInBits() &&
+      (EltSizeInBits % V1.getScalarValueSizeInBits()) == 0 &&
       (EltSizeInBits % V2.getScalarValueSizeInBits()) == 0) {
     bool IsBlend = true;
     unsigned NumV1Elts = V1.getValueType().getVectorNumElements();