[Mesa-dev] i965/fs: load_payload on Gen 7+.

[Matt Turner]

Caveat: I have not tested this on < Gen7 (platforms that send
from MRF). My guess is that I've broken something on those, but
that it shouldn't be a fundamental problem.

Extending this to MRF platforms seems like it'll take a little
bit of extra work, from my 2 minutes of thinking about it.

This series is available in my tree

   git://people.freedesktop.org/~mattst88/mesa tex-sources

i965/fs: Add and use an fs_inst copy constructor.
i965/fs: Disable fs_inst assignment operator.
i965/fs: Combine fs_inst constructors using default
i965/fs: ralloc fs_inst's fs_reg sources.
i965/fs: Store the number of sources an fs_inst has.
i965/fs: Add a function to resize fs_inst's sources
i965/fs: Add fs_inst constructor that takes a list of
i965/fs: Loop from 0 to inst->sources, not 0 to 3.

These change fs_inst to contain a pointer to some ralloc'd
array containing the instructions' sources. I sent some of
these a few months ago hoping to go ahead and get them
reviewed, but not much luck.

i965/fs: Add SHADER_OPCODE_LOAD_PAYLOAD.
i965/fs: Lower LOAD_PAYLOAD and clean up.
i965/fs: Use LOAD_PAYLOAD in emit_texture_gen7().
i965/fs: Apply cube map array fixup and restore the

These add and use the load_payload instruction. It takes a
variable number of arguments, and loads them ito a large
virtual GRF. This will let us avoid partial updates to large
virtual registers when SSA comes. It also allows us to do
some cool optimizations later in the series.

i965/fs: Only consider real sources when comparing
i965/fs: Emit load_payload instead of multiple MOVs for
i965/fs: Support register coalescing on LOAD_PAYLOAD
i965/fs: Perform CSE on load_payload instructions if
i965/fs: Copy propagate from load_payload.

These add support for combining duplicate load_payload instrs,
register coalescing their sources, and copy propagating through
them. With an unreleased title removed from shader-db, the
results from before load_payload to this point are

total instructions in shared programs: 1614283 -> 1614100 (-0.01%)
instructions in affected programs:     3957 -> 3774 (-4.62%)
GAINED:                                9
LOST:                                  1

with a single 299 -> 300 instruction regression in the LOST
program.

i965/fs: Perform CSE on texture operations.

This allows us to CSE duplicate texture operations!

i965/fs: Optimize SEL with the same sources into a MOV.

And a small optimization I noticed when I looked at the results
of texture op CSE.