llvmpipe: Axe texture sampling code inherited from softpipe.
Was used only as a reference, since texture sampling is now code generated.
Already axed in the lp-binning branch too.
This fixes the llvmpipe build after recent sampling changes.
llvmpipe: Autogenerate lp_tile_soa.c from u_format.csv.
This is just a temporary change until we code generate the tile read/write
functions in runtime. The new code avoids an extra memcpy that exists in
u_tile.c functions, from which lp_tile_soa.c was originally based.
This achieves up to 5% improvement, particularly in frames with
little geometry overlap.
llvmpipe: Code generate the texture sampling inside the shader.
Finally a substantial performance improvement: framerates of apps using
texturing tripled, and furthermore, enabling/disabling texturing only
affects around 15% of the framerate, which means the bottleneck is now
somewhere else.
Generated texture sampling code is not complete though -- we always
sample from the base level -- so final figures will be different.
llvmpipe: Factor out and optimize the input interpolation.
Special attention is given to the interpolation of side by side quads.
Multiplications are made only for the first quad. Interpolation of
inputs for posterior quads are done exclusively with additions, and
perspective divide if necessary.