The `static_(num_threads|tile_sizes)` attributes of this op are
`DefaultValuedOptionalAttr`s, so they can be constructed *without* such
an attribute. In other words, the following is a valid op (note the
absense of the `static_num_threads` attribute):
"builtin.module"() ({
"transform.sequence"() <{failure_propagation_mode = 1 : i32, operand_segment_sizes = array<i32: 0, 0>}> ({
^bb0(%arg0: !pdl.operation, %arg1: !transform.op<"linalg.matmul">, %arg2: !transform.op<"linalg.elemwise_binary">):
%0 = "transform.structured.match"(%arg0) <{ops = ["test.dummy"]}> : (!pdl.operation) -> !pdl.operation
%1:2 = "transform.structured.tile_to_forall_op"(%arg1, %0) <{operand_segment_sizes = array<i32: 1, 0, 0, 0, 1>}> : (!transform.op<"linalg.matmul">, !pdl.operation) -> (!transform.op<"scf.forall">, !transform.op<"linalg.matmul">)
"transform.yield"() : () -> ()
}) : () -> ()
}) : () -> ()
However, the custom printing directive converted those to an `ArrayRef`,
which crashes if done on an empty `ArrayAttr`. This patch changes the
signature such that no automatic conversion takes place and extends the
test to test for existinnce of the attribute.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D155062
ab86b8cef4