Commit graph

10 commits

Author SHA1 Message Date
Kenneth Graunke
259cae4442 intel/compiler: Don't create 64-bit src1 immediates in opt_peephole_sel
64-bit immediates are only allowed as src0.  Long ago, we decided to
avoid constructing such illegal situations in the IR, rather than
allowing them in the IR but then promoting bogus immediates to GRFs
later.  So, we need to fix opt_peephole_sel to not put 64-bit immediates
as src1 of the new SEL instruction.

Fixes: a4b36cd3dd ("intel/fs: Coalesce when the src live range is contained in the dst")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2816
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4692>
2020-04-23 00:53:14 +00:00
Francisco Jerez
ab6d792986 intel/compiler: Pass detailed dependency classes to invalidate_analysis()
Have fun reading through the whole back-end optimizer to verify
whether I've missed any dependency flags -- Or alternatively, just
trust that any mistake here will trigger an assertion failure during
analysis pass validation if it ever poses a problem for the
consistency of any of the analysis passes managed by the framework.

Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
2020-03-06 10:20:39 -08:00
Francisco Jerez
d966a6b4c4 intel/compiler: Introduce backend_shader method to propagate IR changes to analysis passes
The invalidate_analysis() method knows what analysis passes there are
in the back-end and calls their invalidate() method to report changes
in the IR.  For the moment it just calls invalidate_live_intervals()
(which will eventually be fully replaced by this function) if anything
changed.

This makes all optimization passes invalidate DEPENDENCY_EVERYTHING,
which is clearly far from ideal -- The dependency classes passed to
invalidate_analysis() will be refined in a future commit.

Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
2020-03-06 10:20:32 -08:00
Juan A. Suarez Romero
b06ae53606 Revert "intel/compiler: split is_partial_write() into two variants"
This reverts commit 40b3abb4d1.

It is not clear that this commit was entirely correct, and unfortunately
it was pushed by error.

CC: Jason Ekstrand <jason@jlekstrand.net>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
2019-04-25 09:19:10 +02:00
Iago Toral Quiroga
40b3abb4d1 intel/compiler: split is_partial_write() into two variants
This function is used in two different scenarios that for 32-bit
instructions are the same, but for 16-bit instructions are not.

One scenario is that in which we are working at a SIMD8 register
level and we need to know if a register is fully defined or written.
This is useful, for example, in the context of liveness analysis or
register allocation, where we work with units of registers.

The other scenario is that in which we want to know if an instruction
is writing a full scalar component or just some subset of it. This is
useful, for example, in the context of some optimization passes
like copy propagation.

For 32-bit instructions (or larger), a SIMD8 dispatch will always write
at least a full SIMD8 register (32B) if the write is not partial. The
function is_partial_write() checks this to determine if we have a partial
write. However, when we deal with 16-bit instructions, that logic disables
some optimizations that should be safe. For example, a SIMD8 16-bit MOV will
only update half of a SIMD register, but it is still a complete write of the
variable for a SIMD8 dispatch, so we should not prevent copy propagation in
this scenario because we don't write all 32 bytes in the SIMD register
or because the write starts at offset 16B (wehere we pack components Y or
W of 16-bit vectors).

This is a problem for SIMD8 executions (VS, TCS, TES, GS) of 16-bit
instructions, which lose a number of optimizations because of this, most
important of which is copy-propagation.

This patch splits is_partial_write() into is_partial_reg_write(), which
represents the current is_partial_write(), useful for things like
liveness analysis, and is_partial_var_write(), which considers
the dispatch size to check if we are writing a full variable (rather
than a full register) to decide if the write is partial or not, which
is what we really want in many optimization passes.

Then the patch goes on and rewrites all uses of is_partial_write() to use
one or the other version. Specifically, we use is_partial_var_write()
in the following places: copy propagation, cmod propagation, common
subexpression elimination, saturate propagation and sel peephole.

Notice that the semantics of is_partial_var_write() exactly match the
current implementation of is_partial_write() for anything that is
32-bit or larger, so no changes are expected for 32-bit instructions.

Tested against ~5000 tests involving 16-bit instructions in CTS produced
the following changes in instruction counts:

            Patched  |     Master    |    %    |
================================================
SIMD8  |    621,900  |    706,721    | -12.00% |
================================================
SIMD16 |     93,252  |     93,252    |   0.00% |
================================================

As expected, the change only affects SIMD8 dispatches.

Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>
2019-04-18 11:05:18 +02:00
Iago Toral Quiroga
e55cbf26ea intel/compiler: fix register allocation in opt_peephole_sel
This wasn't handling 64-bit cases properly. Found by inspection.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2018-11-28 08:28:27 +01:00
Matt Turner
8238930510 i965/fs: Do not move MOVs writing the flag outside of control flow
The implementation of ballotARB() will start by zeroing the flags
register. So, a doing something like

        if (gl_SubGroupInvocationARB % 2u == 0u) {
                ... = ballotARB(true);
		[...]
        } else {
                ... = ballotARB(true);
		[...]
	}

(like fs-ballot-if-else.shader_test does) would generate identical MOVs
to the same destination (the flag register!), and we definitely do not
want to pull that out of the control flow.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2017-07-20 16:56:49 -07:00
Samuel Iglesias Gonsálvez
dee31311eb Revert "i965/fs: Don't emit SEL instructions for type-converting MOVs."
This reverts commit 7dccd38b40.

d2x pass fixes SEL instructions when there is a type conversion
by doing a SEL without type conversion and then convert the result.
This pass also takes into account the non-uniform control flow.

Then, 7dccd38b40 is not needed anymore.

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>
2017-04-14 14:56:07 -07:00
Matt Turner
7dccd38b40 i965/fs: Don't emit SEL instructions for type-converting MOVs.
SEL can only convert between a few integer types, which we basically
never do.

Fixes fs/vs-double-uniform-array-direct-indirect-non-uniform-control-flow
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Acked-by: Francisco Jerez <currojerez@riseup.net>
2017-03-27 10:59:42 -07:00
Jason Ekstrand
700bebb958 i965: Move the back-end compiler to src/intel/compiler
Mostly a dummy git mv with a couple of noticable parts:
 - With the earlier header cleanups, nothing in src/intel depends
files from src/mesa/drivers/dri/i965/
 - Both Autoconf and Android builds are addressed. Thanks to Mauro and
Tapani for the fixups in the latter
 - brw_util.[ch] is not really compiler specific, so it's moved to i965.

v2:
 - move brw_eu_defines.h instead of brw_defines.h
 - remove no-longer applicable includes
 - add missing vulkan/ prefix in the Android build (thanks Tapani)

v3:
 - don't list brw_defines.h in src/intel/Makefile.sources (Jason)
 - rebase on top of the oa patches

[Emil Velikov: commit message, various small fixes througout]
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
2017-03-13 11:16:34 +00:00
Renamed from src/mesa/drivers/dri/i965/brw_fs_sel_peephole.cpp (Browse further)