1 files changed, 21 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/InterleavedAccessPass.cpp b/llvm/lib/CodeGen/InterleavedAccessPass.cpp
index 65565b9..c2839d4 100644
--- a/llvm/lib/CodeGen/InterleavedAccessPass.cpp
+++ b/llvm/lib/CodeGen/InterleavedAccessPass.cpp
@@ -587,6 +587,27 @@ static Value *getMask(Value *WideMask, unsigned Factor,
     }
   }
 
+  if (auto *SVI = dyn_cast<ShuffleVectorInst>(WideMask)) {
+    // Check that the shuffle mask is: a) an interleave, b) all of the same
+    // set of the elements, and c) contained by the first source.  (c) could
+    // be relaxed if desired.
+    unsigned NumSrcElts =
+        cast<FixedVectorType>(SVI->getOperand(1)->getType())->getNumElements();
+    SmallVector<unsigned> StartIndexes;
+    if (ShuffleVectorInst::isInterleaveMask(SVI->getShuffleMask(), Factor,
+                                            NumSrcElts * 2, StartIndexes) &&
+        llvm::all_of(StartIndexes, [](unsigned Start) { return Start == 0; }) &&
+        llvm::all_of(SVI->getShuffleMask(), [&NumSrcElts](int Idx) {
+          return Idx < (int)NumSrcElts;
+        })) {
+      auto *LeafMaskTy =
+          VectorType::get(Type::getInt1Ty(SVI->getContext()), LeafValueEC);
+      IRBuilder<> Builder(SVI);
+      return Builder.CreateExtractVector(LeafMaskTy, SVI->getOperand(0),
+                                         uint64_t(0));
+    }
+  }
+
   return nullptr;
 }