https://bugs.winehq.org/show_bug.cgi?id=38286
--- Comment #3 from Stefan Dösinger stefan@codeweavers.com --- fixme:d3d_shader:get_argreg Implement perstage constants
That says all.
This issue should be fixable. Do you want to take a shot at it? Have a look at how WINED3DTA_CONSTANT is handled in glsl_shader.c and how WINED3DTA_TFACTOR is handled in the arb fixed function pipeline.