-- v8: vkd3d-shader/dxil: Implement DX instruction LoadInput. vkd3d-shader/dxil: Declare shader inputs. vkd3d-shader/dxbc: Load input signatures also from ISG1 chunks. vkd3d-shader/spirv: Build undefined values once. vkd3d-shader/spirv: Introduce a Static Single Assignment register type. vkd3d-shader/d3d-asm: Trace undefined registers. vkd3d-shader: Make the paramater allocator slab size at least MAX_REG_OUTPUT.