Commit Graph

27 Commits

Author SHA1 Message Date
Matt Arsenault 4a36e96c3f RegAllocGreedy: Account for reserved registers in num regs heuristic
This simple heuristic uses the estimated live range length combined
with the number of registers in the class to switch which heuristic to
use. This was taking the raw number of registers in the class, even
though not all of them may be available. AMDGPU heavily relies on
dynamically reserved numbers of registers based on user attributes to
satisfy occupancy constraints, so the raw number is highly misleading.

There are still a few problems here. In the original testcase that
made me notice this, the live range size is incorrect after the
scheduler rearranges instructions, since the instructions don't have
the original InstrDist offsets. Additionally, I think it would be more
appropriate to use the number of disjointly allocatable registers in
the class. For the AMDGPU register tuples, there are a large number of
registers in each tuple class, but only a small fraction can actually
be allocated at the same time since they all overlap with each
other. It seems we do not have a query that corresponds to the number
of independently allocatable registers. Relatedly, I'm still debugging
some allocation failures where overlapping tuples seem to not be
handled correctly.

The test changes are mostly noise. There are a handful of x86 tests
that look like regressions with an additional spill, and a handful
that now avoid a spill. The worst looking regression is likely
test/Thumb2/mve-vld4.ll which introduces a few additional
spills. test/CodeGen/AMDGPU/soft-clause-exceeds-register-budget.ll
shows a massive improvement by completely eliminating a large number
of spills inside a loop.
2021-09-14 21:00:29 -04:00
Joe Nash 3ce1b9631a [AMDGPU] Switch PostRA sched to MachineSched
Use GCNHazardRecognizer in postra sched.
Updated tests for the new schedules.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D109536

Change-Id: Ia86ba2ae168f12fb34b4d8efdab491f84d936cde
2021-09-14 15:11:27 -04:00
Baptiste Saleil 54c0f520c7 [VirtRegRewriter] Insert missing killed flags when tracking subregister liveness
VirtRegRewriter may sometimes fail to correctly apply the kill flag where necessary,
which causes unecessary code gen on PowerPC. This patch fixes the way masks for
defined lanes are computed and the way mask for used lanes is computed.

Contact albion.fung@ibm.com instead of author for problems related to this commit.

Differential Revision: https://reviews.llvm.org/D92405
2021-03-03 12:02:04 -05:00
Austin Kerbow 2291bd137d [AMDGPU] Update subtarget features for new target ID support
Support for XNACK and SRAMECC is not static on some GPUs. We must be able
to differentiate between different scenarios for these dynamic subtarget
features.

The possible settings are:

- Unsupported: The GPU has no support for XNACK/SRAMECC.
- Any: Preference is unspecified. Use conservative settings that can run anywhere.
- Off: Request support for XNACK/SRAMECC Off
- On: Request support for XNACK/SRAMECC On

GCNSubtarget will track the four options based on the following criteria. If
the subtarget does not support XNACK/SRAMECC we say the setting is
"Unsupported". If no subtarget features for XNACK/SRAMECC are requested we
must support "Any" mode. If the subtarget features XNACK/SRAMECC exist in the
feature string when initializing the subtarget, the settings are "On/Off".

The defaults are updated to be conservatively correct, meaning if no setting
for XNACK or SRAMECC is explicitly requested, defaults will be used which
generate code that can be run anywhere. This corresponds to the "Any" setting.

Differential Revision: https://reviews.llvm.org/D85882
2021-01-26 11:25:51 -08:00
Mircea Trofin b470630913 [NFC] Removed unused prefixes from CodeGen/AMDGPU
All the 'l'-starting tests.

Differential Revision: https://reviews.llvm.org/D94151
2021-01-06 09:34:11 -08:00
Simon Pilgrim cb798f040a [DAG] computeKnownBits - Move (most) ISD::SRL handling into KnownBits::lshr
As discussed on D90527, we should be be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.

The refactor to use the KnownBits fixed/min/max constant helpers allows us to hit a couple of cases that we were missing before.

We still need the getValidMinimumShiftAmountConstant case as KnownBits doesn't handle per-element vector cases.
2020-11-03 17:30:36 +00:00
Simon Pilgrim c06c02bd1f [AMDGPU] Regenerate load i16 tests to use update_llc_test_checks.py script. NFCI.
Necessary for upcoming KnownBits::lshr support.
2020-11-03 17:30:36 +00:00
Justin Bogner b1650f0da9 [LegalizeVectorTypes] Allow single loads and stores for more short vectors
When lowering a load or store for TypeWidenVector, the type legalizer
would use a single load or store if the associated integer type was legal
or promoted. E.g. it loads a v4i8 as an i32 if i32 is legal/promotable.
(See https://reviews.llvm.org/rL236528 for reference.)

This applies that behaviour to vector types. If the vector type is
TypePromoteInteger, the element type is going to be TypePromoteInteger
as well, which will lead to have a single promoting load rather than N
individual promoting loads. For instance, if we have a v3i1, we would
now have a load of v4i1 instead of 3 loads of i1.

Patch by Guillaume Marques. Thanks!

Differential Revision: https://reviews.llvm.org/D56201

llvm-svn: 357120
2019-03-27 20:35:56 +00:00
Joel E. Denny 9fa9c9368d [FileCheck] Add -allow-deprecated-dag-overlap to failing llvm tests
See https://reviews.llvm.org/D47106 for details.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47171

This commit drops that patch's changes to:

  llvm/test/CodeGen/NVPTX/f16x2-instructions.ll
  llvm/test/CodeGen/NVPTX/param-load-store.ll

For some reason, the dos line endings there prevent me from commiting
via the monorepo.  A follow-up commit (not via the monorepo) will
finish the patch.

llvm-svn: 336843
2018-07-11 20:25:49 +00:00
Matt Arsenault 6c041a3cab AMDGPU: Fix selection error on constant loads with < 4 byte alignment
llvm-svn: 328818
2018-03-29 19:59:28 +00:00
Balaram Makam 42adadfca0 Re-land MachineInstr: Reason locally about some memory objects before going to AA.
Summary:
Reverts r311008 to reinstate r310825 with a fix.

Refine alias checking for pseudo vs value to be conservative.
This fixes the original failure in builtbot unittest SingleSource/UnitTests/2003-07-09-SignedArgs.

Reviewers: hfinkel, nemanjai, efriedma

Reviewed By: efriedma

Subscribers: bjope, mcrosier, nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D36900

llvm-svn: 312126
2017-08-30 14:57:12 +00:00
Balaram Makam c5698befb6 Revert "MachineInstr: Reason locally about some memory objects before going to AA."
r310825 caused the clang-ppc64le-linux-lnt bot to go red
(http://lab.llvm.org:8011/builders/clang-ppc64le-linux-lnt/builds/5712)
because of a test-suite failure of
SingleSource/UnitTests/2003-07-09-SignedArgs

This reverts commit 0028f6a87224fb595a1c19c544cde9b003035996.

llvm-svn: 311008
2017-08-16 14:17:43 +00:00
Balaram Makam d9f53414de MachineInstr: Reason locally about some memory objects before going to AA.
This addresses a FIXME in MachineInstr::mayAlias.

llvm-svn: 310825
2017-08-14 09:41:40 +00:00
Alexander Timofeev 982aee6a38 [AMDGPU] Switch scalarize global loads ON by default
Differential revision: https://reviews.llvm.org/D34407

llvm-svn: 307097
2017-07-04 17:32:00 +00:00
NAKAMURA Takumi e4a741376b Revert r307026, "[AMDGPU] Switch scalarize global loads ON by default"
It broke a testcase.

  Failing Tests (1):
      LLVM :: CodeGen/AMDGPU/alignbit-pat.ll

llvm-svn: 307054
2017-07-04 02:14:18 +00:00
Alexander Timofeev ea7f08bee5 [AMDGPU] Switch scalarize global loads ON by default
Differential revision: https://reviews.llvm.org/D34407

llvm-svn: 307026
2017-07-03 14:54:11 +00:00
Simon Pilgrim c910a70b21 [AMDGPU] Add INDIRECT_BASE_ADDR to R600_Reg32 class (PR33045)
This fixes 17 of the 41 -verify-machineinstrs test failures identified in PR33045

Differential Revision: https://reviews.llvm.org/D33451

llvm-svn: 303691
2017-05-23 21:27:15 +00:00
Matt Arsenault 3dbeefa978 AMDGPU: Mark all unspecified CC functions in tests as amdgpu_kernel
Currently the default C calling convention functions are treated
the same as compute kernels. Make this explicit so the default
calling convention can be changed to a non-kernel.

Converted with perl -pi -e 's/define void/define amdgpu_kernel void/'
on the relevant test directories (and undoing in one place that actually
wanted a non-kernel).

llvm-svn: 298444
2017-03-21 21:39:51 +00:00
Matt Arsenault 7aad8fd8f4 Enable FeatureFlatForGlobal on Volcanic Islands
This switches to the workaround that HSA defaults to
for the mesa path.

This should be applied to the 4.0 branch.

Patch by Vedran Miletić <vedran@miletic.net>

llvm-svn: 292982
2017-01-24 22:02:15 +00:00
Jan Vesely 06200bd7bc AMDGPU/R600: Don't use REGISTER_{LOAD,STORE} ISD nodes
This will make transition to SCRATCH_MEMORY easier

Differential Revision: https://reviews.llvm.org/D24746

llvm-svn: 291279
2017-01-06 21:00:46 +00:00
Tom Stellard 115a61560e AMDGPU: Add VI i16 support
Patch By: Wei Ding

Differential Revision: https://reviews.llvm.org/D18049

llvm-svn: 286464
2016-11-10 16:02:37 +00:00
Tom Stellard 2d2d33f1dc Revert "AMDGPU: Add VI i16 support"
This reverts commit r285939 and r285948.  These broke some conformance tests.

llvm-svn: 285995
2016-11-04 13:06:34 +00:00
Tom Stellard 2b3379cdff AMDGPU: Add VI i16 support
Patch By: Wei Ding

Differential Revision: https://reviews.llvm.org/D18049

llvm-svn: 285939
2016-11-03 17:13:50 +00:00
Simon Pilgrim cc7b4b511b [SelectionDAG] Add BUILD_VECTOR support to computeKnownBits and SimplifyDemandedBits
Add the ability to computeKnownBits and SimplifyDemandedBits to extract the known zero/one bits from BUILD_VECTOR, returning the known bits that are shared by every vector element.

This is an initial step towards determining the sign bits of a vector (PR29079).

Differential Revision: https://reviews.llvm.org/D24253

llvm-svn: 280927
2016-09-08 12:57:51 +00:00
Jan Vesely 38814fa2fd AMDGPU/R600: Enable Load combine
Fix and improve tests

Differential Revision: https://reviews.llvm.org/D23899

llvm-svn: 279925
2016-08-27 19:09:43 +00:00
Matt Arsenault 327bb5ad82 AMDGPU: Improve load/store of illegal types.
There was a combine before to handle the simple copy case.
Split this into handling loads and stores separately.

We might want to change how this handles some of the vector
extloads, since this can result in large code size increases.

llvm-svn: 274394
2016-07-01 22:47:50 +00:00
Matt Arsenault d1097a38e2 AMDGPU: Cleanup load tests
There are a lot of different kinds of loads to test for,
and these were scattered around inconsistently with
some redundancy. Try to comprehensively test all loads
in a consistent way.

llvm-svn: 271571
2016-06-02 19:54:26 +00:00