[llvm] r308312 - [DAG] Allow base element type of store merge type to also be a vector.

[Nirav Dave via llvm-commits]

Author: niravd
Date: Tue Jul 18 07:39:09 2017
New Revision: 308312

URL: http://llvm.org/viewvc/llvm-project?rev=308312&view=rev
Log:
[DAG] Allow base element type of store merge type to also be a vector.

Correctly calculate merged vector size if MemVT is already a vector.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=308312&r1=308311&r2=308312&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Tue Jul 18 07:39:09 2017
@@ -12763,7 +12763,12 @@ bool DAGCombiner::MergeConsecutiveStores
              TLI.storeOfVectorConstantIsCheap(MemVT, i + 1, FirstStoreAS)) &&
             !NoVectors) {
           // Find a legal type for the vector store.
-          EVT Ty = EVT::getVectorVT(Context, MemVT, i + 1);
+          unsigned Elts = i + 1;
+          if (MemVT.isVector()) {
+            // When merging vector stores, get the total number of elements.
+            Elts *= MemVT.getVectorNumElements();
+          }
+          EVT Ty = EVT::getVectorVT(Context, MemVT.getScalarType(), Elts);
           if (TLI.isTypeLegal(Ty) &&
               TLI.canMergeStoresTo(FirstStoreAS, Ty, DAG) &&
               TLI.allowsMemoryAccess(Context, DL, Ty, FirstStoreAS,