message: Added mlir tests for dynamic strided slice
  Strided slice has no tests for dynamically shaped tensors. Included some simple
  examples for lowerings when the Shape dialect is ready.
diff: @@ -2180,6 +2180,18 @@ func @simple_strided_slice(%input: tensor<4x8xf32>) -> tensor<3x2xf32> {
  return %output : tensor<3x2xf32>
  }
  +// CHECK-LABEL: dynamic_strided_slice
  +func @dynamic_strided_slice(%input: tensor<?x8xf32>) -> tensor<?x2xf32> {
  + %begin = "tf.Const"() {value = dense<[0, 1]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  + %end = "tf.Const"() {value = dense<[3, 7]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  + %strides = "tf.Const"() {value = dense<[1, 3]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  +
  + // CHECK: "tf.StridedSlice"
  + %output = "tf.StridedSlice"(%input, %begin, %end, %strides)
  + : (tensor<?x8xf32>, tensor<2xi32>, tensor<2xi32>, tensor<2xi32>) -> tensor<?x2xf32>
  + return %output : tensor<?x2xf32>
  +}
  +
  // CHECK-LABEL: strided_slice_negative_indices
  func @strided_slice_negative_indices(%input: tensor<4x8xf32>) -> tensor<3x2xf32> {
  %begin = "tf.Const"() {value = dense<[-1, -2]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  @@ -2199,6 +2211,18 @@ func @strided_slice_negative_indices(%input: tensor<4x8xf32>) -> tensor<3x2xf32>
  return %output : tensor<3x2xf32>
  }
  +// CHECK-LABEL: dynamic_strided_slice_negative_indices
  +func @dynamic_strided_slice_negative_indices(%input: tensor<?x8xf32>) -> tensor<?x2xf32> {
  + %begin = "tf.Const"() {value = dense<[-1, -2]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  + %end = "tf.Const"() {value = dense<[-4, -8]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  + %strides = "tf.Const"() {value = dense<[-1, -3]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  +
  + // CHECK: tf.StridedSlice
  + %output = "tf.StridedSlice"(%input, %begin, %end, %strides)
  + : (tensor<?x8xf32>, tensor<2xi32>, tensor<2xi32>, tensor<2xi32>) -> tensor<?x2xf32>
  + return %output : tensor<?x2xf32>
  +}
  +
  // CHECK-LABEL: strided_slice_range_clamping
  func @strided_slice_range_clamping(%input: tensor<4x8xf32>) -> tensor<0x3xf32> {
  %begin = "tf.Const"() {value = dense<[-4, -10]> : tensor<2xi32>} : () -> (tensor<2xi32>)
  