When combining (vextract shuffle (load ), <1,u,u,u>), 0) -> (load ), add users of the final load to the worklist too. Needed by changes I'm preparing to make to X86 backend.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153078 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/SelectionDAG/DAGCombiner.cpp

@@ -7353,6 +7353,7 @@ SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) {
     // Since we're explcitly calling ReplaceAllUses, add the new node to the
     // worklist explicitly as well.
     AddToWorkList(Load.getNode());
+    AddUsersToWorkList(Load.getNode()); // Add users too
     // Make sure to revisit this node to clean it up; it will usually be dead.
     AddToWorkList(N);
     return SDValue(N, 0);