-- v21: vkd3d-shader/ir: Include an initial label instruction in the first control flow block. vkd3d-shader/ir: Store code block names in struct vkd3d_shader_desc. vkd3d-shader/ir: Flatten SWITCH/CASE/DEFAULT/ENDSWITCH control flow instructions. vkd3d-shader/ir: Flatten LOOP/BREAK/CONTINUE/ENDLOOP control flow instructions. vkd3d-shader/ir: Flatten IF/ELSE/ENDIF control flow instructions.