diff --git a/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td b/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
--- a/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
+++ b/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
@@ -295,7 +295,7 @@
 def LLVM_AllocaOp : LLVM_Op<"alloca">, MemoryOpWithAlignmentBase {
   let arguments = (ins AnyInteger:$arraySize,
                    OptionalAttr<I64Attr>:$alignment);
-  let results = (outs LLVM_AnyPointer:$res);
+  let results = (outs Res<LLVM_AnyPointer, "", [MemAlloc<AutomaticAllocationScopeResource>]>:$res);
   string llvmBuilder = [{
     auto *inst = builder.CreateAlloca(
       $_resultType->getPointerElementType(), $arraySize);
diff --git a/mlir/test/Dialect/LLVMIR/canonicalize.mlir b/mlir/test/Dialect/LLVMIR/canonicalize.mlir
--- a/mlir/test/Dialect/LLVMIR/canonicalize.mlir
+++ b/mlir/test/Dialect/LLVMIR/canonicalize.mlir
@@ -122,3 +122,11 @@
   %0 = llvm.mlir.addressof @fp : !llvm.ptr<ptr<i8>>
   llvm.return 
 }
+
+// CHECK-LABEL: alloca_dce
+// CHECK-NEXT: llvm.return
+llvm.func @alloca_dce() {
+  %c1_i64 = arith.constant 1 : i64
+  %0 = llvm.alloca %c1_i64 x i32 : (i64) -> !llvm.ptr<i32>
+  llvm.return 
+}