ARM: make sure we use all entries in a vector before forming a vpaddl.

Otherwise there's some mismatch, and we'll either form an illegal type or an
illegal node.

Thanks to Eli Friedman for pointing out the problem with my original solution.

llvm-svn: 301036

1 files changed, 5 insertions, 5 deletions

diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index df840d723e3..382f881f774 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -9480,11 +9480,11 @@ AddCombineBUILD_VECTORToVPADDL(SDNode *N, SDValue N0, SDValue N1,
       return SDValue();
   }
 
-  // Don't generate vpaddl+vmovn; we'll match it to vpadd later. Also don't try
-  // to handle an i8 -> i32 situation (or similar). vpaddl can only double the
-  // size.
-  if (2 * Vec.getValueType().getVectorElementType().getSizeInBits() !=
-      VT.getVectorElementType().getSizeInBits())
+  // Don't generate vpaddl+vmovn; we'll match it to vpadd later. Also make sure
+  // we're using the entire input vector, otherwise there's a size/legality
+  // mismatch somewhere.
+  if (nextIndex != Vec.getValueType().getVectorNumElements() ||
+      Vec.getValueType().getVectorElementType() == VT.getVectorElementType())
     return SDValue();
 
   // Create VPADDL node.