xfb_decl_assign_location() assumes that arrays are going to be packed.
But some conditions might prevent packing (e.g: explicit location or
smooth interpolation mode).
Instead of assuming that packing will happen, this commit adds a check to
determine if it'll happen and use the result to compute the proper location.
Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2214
Acked-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18175>
Otherwise we will mix and match mesa's custom cross slot packing
with arb_enhanced_layouts style packing and we won't correctly
handle the size of the vars needed for the mesa custom packing.
The code was working correctly if the shader interface had both
a matching input and output but when we only had one side of
the interface we were only marking a single slot location as
packed.
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Fixes: e5122a5543 ("glsl: add a NIR based varying linker")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6853
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17550>
With a NIR based linker we get better xfb packing, and we no longer
depend on the GLSL IR optimisations to be able to link shaders
with a large amount of dead input/outputs.
Acked-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15731>
