Summary:
The point of this is to make some tests with manual checks robust
against scheduler tweaks, so that only autogenerated test updates will
be required when pushing D68338 "[AMDGPU] Remove dubious logic in
bidirectional list scheduler".
Reviewers: arsenm, rampitec, vpykhtin
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75302
Summary:
The affected LIT test intends to test the correct use of divergence
analysis to detect a divergent branch with a uniform predicate. The
passes involved are LLVM IR passes, but the test runs llc and tries to
match against generated ISA, which makes it hard to demonstrate that
the intended behavior was really tested. Replaced this with a test
that invokes opt on the required passes and then checks for the
appropriate changes in the LLVM IR.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D75267
Summary:
The old code made some incorrect assumptions about the order in which
basic blocks are laid out in a function. This could lead to incorrect
early-exits, especially when kills occurred inside of loops.
The new approach is to check whether the point where the conditional
kill occurs dominates all reachable code. If that is the case, there
cannot be any other threads in the wave that are waiting to rejoin
at a later point in the CFG, i.e. if exec=0 at that point, then all
threads really are dead and we can exit the wave.
Make some other minor cleanups to the pass while we're at it.
v2: preserve the dominator tree
Reviewers: arsenm, cdevadas, foad, critson
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74908
Change-Id: Ia0d2b113ac944ad642d1c622b6da1b20aa1aabcc
The current set of custom combines are only really useful after
legalization, so move them there. There is a lot of overlap in the
boilerplate here, but I think we do want a pretty different set of
combines before and after legalize. I think we will want a lot of
overlap between the post-legalize and a post-regbankselect combiner.
Changes the handling of odd breakdowns, and avoids using
G_EXTRACT/G_INSERT. Pad with undef to a wider size, and unmerge. Also
avoid introducing instructions for the fully undef components.
This reverts commit 977cd661cf.
It breaks OpenCL testing. OpenCL Runtime is using PT_LOAD information
to calculate memory for global variables. This commit should be relanded once
the OpenCL runtime stops relying on PT_LOAD information for calculating global
variable memory size.
Differential Revision: https://reviews.llvm.org/D74995
The legalizer helper functions are unusably awkward to perform the 3-5
part legalization. This needs to be widened, scalarized, lowered, and
we should avoid creating vector extends and truncates. Manually do all
of this and expand.
I tried to use some of the new tablegen features to avoid creating
different operand list permutations, but I still don't see a way to
programmatically build a source pattern dag.
Also add GlobalISel tests, which now all import successfully.
Some of the fneg fold tests are incorrect, which need to be fixed in a
future commit
G_SHUFFLE_VECTOR is legal since it theoretically may help match op_sel
for VOP3P instructions. Expand it in some other way in case it doesn't
fold into the use instructions.
We should try the generated matchers before the manual selection. This
means the patterns are now handling the common cases, but the manual
selection code is not yet dead. It's still handling the non-s32/s64
cases (like v2s16 and v2s32). Currently tablegen doesn't have a nice
way to have a single pattern that covers multiple types.
We have patterns for s_pack* selection, but they assume the inputs are
a build_vector with 16-bit inputs, not a truncating build
vector. Since there's still outstanding work for how to handle
mismatched result and source element vector operations, and since I'm
trying a different packed vector strategy than SelectionDAG, just
manually select this for now.
There are few differences from the DAG handling. First, the DAG
handling uses a primitive selection pattern instead of custom
legalizing it. Because of this, this makes use of source modifiers
while the DAG does not.
Also instead of promoting f16, try to use the f16 log/exp. There's no
f16 fmul_legacy, so widen just for the multiply, although I'm not sure
that's the best solution.
This looked through copies to find the source modifiers, which may
have been SGPR->VGPR copies added to avoid potential constant bus
violations. Re-insert a copy to a VGPR if this happens.
Similar to what we already do with SimplifyDemandedVectorElts, call SimplifyDemandedBits across all the extracted elements of the source vector, treating it as single use.
There's a minor regression in store-weird-sizes.ll which will be addressed in an upcoming SimplifyDemandedBits patch.
Marking a section as ALLOC tells the ELF loader to load the section into memory.
As we do not want to load the notes into VRAM, the flag should not be there.
Differential Revision: https://reviews.llvm.org/D74600
GetDemandedBits mostly just calls SimplifyMultipleUseDemandedBits now, but it does a very blunt constant simplification that SimplifyMultipleUseDemandedBits avoids.
If we need to demand bits from constants we should handle this through ShrinkDemandedConstant/targetShrinkDemandedConstant.
@arsenm confirmed that the sign extended immediates are better for code size.
Differential Revision: https://reviews.llvm.org/D74857
Summary:
After updating cost model in AMDGPU target (47a5c36b37) the pass started to
ignore some BBs since they got all instructions estimated as free.
Reviewers: arsenm, chandlerc, nhaehnle
Reviewed By: nhaehnle
Subscribers: jvesely, wdng, nhaehnle, tpr, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74825
We probably want this, and I've meant to turn this on for a long
time. SC actually emits a special case to early-out for a 1
denominator, which perhaps should also be considered.
Use common check prefix, although update_mir_test_checks makes this
unnecessarily annoying. Also make sure to have uses in case that ever
ends up mattering.
This is part of the work to remove SelectionDAG::GetDemandedBits and just use SimplifyMultipleUseDemandedBits.
Recent experiments raised some v_cvt_f32_ubyte*_e32 regressions, so I've added some additional abilities to performCvtF32UByteNCombine to help unpack byte data more aggressively.
We still don't remove all OR(SHL,SRL) patterns as some of the regenerated nodes don't get combined again, but we are getting closer.
Differential Revision: https://reviews.llvm.org/D74786
AMDGPUCodeGenPrepare expands this most of the time, but not always. We
will always at least need a fallback option here. This is the 3rd
implementation of the same expansion in the backend. Eventually I
would like to eliminate the IR expansion (and the DAG version
obviously).
Currently the new legalizer path produces a better result, since the
IR expansion results in extra operations which need to be combined
out. Notably, the IR expansion results in multiplies by 0.
Jay Foad