Loop unswitching can be extremely harmful for a SIMT target. In case
if hoisted condition is not uniform a SIMT machine will execute both
clones of a loop sequentially. Therefor LoopUnswitch checks if the
condition is non-divergent.
Since DivergenceAnalysis adds an expensive PostDominatorTree analysis
not needed for non-SIMT targets a new option is added to avoid unneded
analysis initialization. The method getAnalysisUsage is called when
TargetTransformInfo is not yet available and we cannot use it here.
For that reason a new field DivergentTarget is added to PassManagerBuilder
to control the behavior and set this field from a target.
Differential Revision: https://reviews.llvm.org/D30796
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298104 91177308-0d34-0410-b5e6-96231b3b80d8
We can mark functions to always inline early in the opt. Since we do not have
call support this early inlining creates opportunities for inter-procedural
optimizations which would not occur otherwise.
Differential Revision: https://reviews.llvm.org/D31016
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297958 91177308-0d34-0410-b5e6-96231b3b80d8
This patch reverts region's scheduling to the original untouched state
in case if we have have decreased occupancy.
In addition it switches to use TargetRegisterInfo occupancy callback
for pressure limits instead of gradually increasing limits which were
just passed by. We are going to stay with the best schedule so we do
not need to tolerate worsened scheduling anymore.
Differential Revision: https://reviews.llvm.org/D29971
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295206 91177308-0d34-0410-b5e6-96231b3b80d8
Since we have no call support and late linking we can produce code
only for used symbols. This saves compilation time, size of the final
executable, and size of any intermediate dumps.
Run Internalize pass early in the opt pipeline followed by global
DCE pass. To enable it RT can pass -amdgpu-internalize-symbols option.
Differential Revision: https://reviews.llvm.org/D29214
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293549 91177308-0d34-0410-b5e6-96231b3b80d8
This change introduces adjustPassManager target callback giving a
target an opportunity to tweak PassManagerBuilder before pass
managers are populated.
This generalizes and replaces addEarlyAsPossiblePasses target
callback. In particular that can be used to add custom passes to
extension points other than EP_EarlyAsPossible.
Differential Revision: https://reviews.llvm.org/D28336
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293189 91177308-0d34-0410-b5e6-96231b3b80d8
Leave early ifcvt disabled for now since there are some
shader-db regressions.
This causes some immediate improvements, but could be better.
The cost checking that the pass does is based on critical path
length for out of order CPUs which we do not want so it skips out
on many cases we want.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293016 91177308-0d34-0410-b5e6-96231b3b80d8
Regalloc creates COPY instructions which do not formally use VALU.
That results in v_mov instructions displaced after exec mask modification.
One pass which do it is SIOptimizeExecMasking, but potentially it can be
done by other passes too.
This patch adds a pass immediately after regalloc to add implicit exec
use operand to all VGPR copy instructions.
Differential Revision: https://reviews.llvm.org/D28874
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292956 91177308-0d34-0410-b5e6-96231b3b80d8
Multiple metadata values for records such as opencl.ocl.version, llvm.ident
and similar are created after linking several modules. For some of them, notably
opencl.ocl.version, this creates semantic problem because we cannot tell which
version of OpenCL the composite module conforms.
Moreover, such repetitions of identical values often create a huge list of
unneeded metadata, which grows bitcode size both in memory and stored on disk.
It can go up to several Mb when linked against our OpenCL library. Lastly, such
long lists obscure reading of dumped IR.
The pass unifies metadata after linking.
Differential Revision: https://reviews.llvm.org/D25381
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289092 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
LC can currently select scalar load for uniform memory access
basing on readonly memory address space only. This restriction
originated from the fact that in HW prior to VI vector and scalar caches
are not coherent. With MemoryDependenceAnalysis we can check that the
memory location corresponding to the memory operand of the LOAD is not
clobbered along the all paths from the function entry.
Reviewers: rampitec, tstellarAMD, arsenm
Subscribers: wdng, arsenm, nhaehnle
Differential Revision: https://reviews.llvm.org/D26917
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289076 91177308-0d34-0410-b5e6-96231b3b80d8
The structured CFG is just an aid to inserting exec
mask modification instructions, once that is done
we don't really need it anymore. We also
do not analyze blocks with terminators that
modify exec, so this should only be impacting
true branches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288744 91177308-0d34-0410-b5e6-96231b3b80d8
This makes the createGenericSchedLive() function that constructs the
default scheduler available for the public API. This should help when
you want to get a scheduler and the default list of DAG mutations.
This also shrinks the list of default DAG mutations:
{Load|Store}ClusterDAGMutation and MacroFusionDAGMutation are no longer
added by default. Targets can easily add them if they need them. It also
makes it easier for targets to add alternative/custom macrofusion or
clustering mutations while staying with the default
createGenericSchedLive(). It also saves the callback back and forth in
TargetInstrInfo::enableClusterLoads()/enableClusterStores().
Differential Revision: https://reviews.llvm.org/D26986
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288057 91177308-0d34-0410-b5e6-96231b3b80d8
Also respect the TII hook for these like the generic code does
in case we want a flag later to disable this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287021 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes to allow spilling all registers at the end of the block
work with exec modifications. Don't emit s_and_saveexec_b64 for
if lowering, and instead emit copies. Mark control flow mask
instructions as terminators to get correct spill code placement
with fast regalloc, and then have a separate optimization pass
form the saveexec.
This should work if SGPRs are spilled to VGPRs, but
will likely fail in the case that an SGPR spills to memory
and no workitem takes a divergent branch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282667 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The SILoadStoreOptimizer can now look ahead more then one instruction when
looking for instructions to merge, which greatly improves the number of
loads/stores that we are able to merge.
Moving the pass before scheduling avoids increasing register pressure after
the scheduler, so that the scheduler's register pressure estimates will be
more accurate. It also gives more consistent results, since it is no longer
affected by minor scheduling changes.
Reviewers: arsenm
Subscribers: arsenm, kzhuravl, llvm-commits
Differential Revision: https://reviews.llvm.org/D23814
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279991 91177308-0d34-0410-b5e6-96231b3b80d8
Do most of the lowering in a pre-RA pass. Keep the skip jump
insertion late, plus a few other things that require more
work to move out.
One concern I have is now there may be COPY instructions
which do not have the necessary implicit exec uses
if they will be lowered to v_mov_b32.
This has a positive effect on SGPR usage in shader-db.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279464 91177308-0d34-0410-b5e6-96231b3b80d8
minimal and boring form than the old pass manager's version.
This pass does the very minimal amount of work necessary to inline
functions declared as always-inline. It doesn't support a wide array of
things that the legacy pass manager did support, but is alse ... about
20 lines of code. So it has that going for it. Notably things this
doesn't support:
- Array alloca merging
- To support the above, bottom-up inlining with careful history
tracking and call graph updates
- DCE of the functions that become dead after this inlining.
- Inlining through call instructions with the always_inline attribute.
Instead, it focuses on inlining functions with that attribute.
The first I've omitted because I'm hoping to just turn it off for the
primary pass manager. If that doesn't pan out, I can add it here but it
will be reasonably expensive to do so.
The second should really be handled by running global-dce after the
inliner. I don't want to re-implement the non-trivial logic necessary to
do comdat-correct DCE of functions. This means the -O0 pipeline will
have to be at least 'always-inline,global-dce', but that seems
reasonable to me. If others are seriously worried about this I'd like to
hear about it and understand why. Again, this is all solveable by
factoring that logic into a utility and calling it here, but I'd like to
wait to do that until there is a clear reason why the existing
pass-based factoring won't work.
The final point is a serious one. I can fairly easily add support for
this, but it seems both costly and a confusing construct for the use
case of the always inliner running at -O0. This attribute can of course
still impact the normal inliner easily (although I find that
a questionable re-use of the same attribute). I've started a discussion
to sort out what semantics we want here and based on that can figure out
if it makes sense ta have this complexity at O0 or not.
One other advantage of this design is that it should be quite a bit
faster due to checking for whether the function is a viable candidate
for inlining exactly once per function instead of doing it for each call
site.
Anyways, hopefully a reasonable starting point for this pass.
Differential Revision: https://reviews.llvm.org/D23299
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278896 91177308-0d34-0410-b5e6-96231b3b80d8
This adds the actual MachineLegalizeHelper to do the work and a trivial pass
wrapper that legalizes all instructions in a MachineFunction. Currently the
only transformation supported is splitting up a vector G_ADD into one acting on
smaller vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276461 91177308-0d34-0410-b5e6-96231b3b80d8
If 2.5 ulp is acceptable, denormals are not required, and
isn't a reciprocal which will already be handled, replace
with a faster fdiv.
Simplify the lowering tests by using per function
subtarget features.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276051 91177308-0d34-0410-b5e6-96231b3b80d8
The only real reason to use it is for testing, so replace
it with a command line option instead of a potentially function
dependent feature.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273653 91177308-0d34-0410-b5e6-96231b3b80d8
Split AMDGPUSubtarget into amdgcn/r600 specific subclasses.
This removes most of the static_casting of the basic codegen
classes everywhere, and tries to restrict the features
visible on the wrong target.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273652 91177308-0d34-0410-b5e6-96231b3b80d8
