This applies on top of !662, the last four commits belong here.
Here we compute a topological order (plus some additional properties) of the shader blocks. Eventually the blocks will be emitted precisely in this order, after having been enriched with structured control flow information.
-- v5: vkd3d-shader/ir: Keep loops contiguous in the topological sort. vkd3d-shader/ir: Dump the topological order of the control flow graph. vkd3d-shader/ir: Topologically sort the control flow graph. vkd3d-shader/ir: Allow adding to a block list without checking for duplicates. vkd3d-shader/ir: Sort each loop by block label. vkd3d-shader/ir: Dump the loops in the control flow graph. vkd3d-shader/ir: Keep track of loops by header block.