Improve code stability by only registering the results of memref.alloc or memref.assume_alignment as input memrefs (Xilinx#1043)

* Improve code stability by filtering op using Pure interface

* More restrictive op filtering: limiting to only registering alloc and assume_alignment as inputs

Author: erwei-xilinx

mlir/lib/Util/Util.cpp

@@ -1914,7 +1914,7 @@ struct BufferMemrefToFuncArgsPattern : public OpRewritePattern<func::FuncOp> {
     SmallVector<Type, 6> memrefTypes;
     llvm::SetVector<Value> memrefs;
     for (auto &op : funcOp.getFunctionBody().getOps()) {
-      if (isa<CastOpInterface, UnrealizedConversionCastOp>(op))
+      if (!isa<memref::AllocOp, memref::AssumeAlignmentOp>(op))
         continue;
       for (auto res : op.getResults()) {
         BaseMemRefType resType = dyn_cast<BaseMemRefType>(res.getType());