Commit Graph

254 Commits

Author SHA1 Message Date
Matt Arsenault 3b95986a32 AMDGPU: Run AMDGPUCodeGenPrepare after scalar opts
The mul24 matching could interfere with SLSR and the other addressing
mode related passes. This probably is not the optimal placement, but
is an intermediate step. This should probably be moved after all the
generic IR passes, particularly LSR. Moving this after LSR seems to
help in some cases, and hurts others.

As-is in this patch, in idiv-licm, it saves 1-2 instructions inside
some of the loop bodies, but increases the number in others. Moving
this later helps these loops. In the new lsr tests in
mul24-pass-ordering, the intrinsic prevents introducing more
instructions in the loop preheader, so moving this later ends up
hurting them. This shouldn't be any worse than before the intrinsics
were introduced in r366094, and LSR should probably be smarter. I
think it's because it doesn't know the and inside the loop will be
folded away.

llvm-svn: 369991
2019-08-27 00:08:31 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Stanislav Mekhanoshin 4c9c98f36b [AMDGPU] Printf runtime binding pass
This pass is a port of the according pass from the HSAIL compiler.
It parses printf calls and setup runtime printf buffer.
After that it copies printf arguments to the buffer and fills in
module metadata for runtime.

Differential Revision: https://reviews.llvm.org/D24035

llvm-svn: 368592
2019-08-12 17:12:29 +00:00
Michael Liao 53f967f2bd [AMDGPU] Run `unreachable-mbb-elimination` after isel to clean up PHIs.
Summary:
- As LCSSA is turned on just before isel, it may create PHI of the flow,
  which is consumed by pseudo structurized CFG instructions. When that
  PHIs are eliminated in O0, COPY may be placed wrongly as the these
  pseudo structurized CFG instructions are considering prologue of MBB.
- Run extra `unreachable-mbb-elimination` at the end of isel to clean up
  PHIs.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64353

llvm-svn: 367023
2019-07-25 14:50:18 +00:00
Michael Liao b3f967d411 [AMDGPU] Add the adjusted FP as a livein register.
Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64145

llvm-svn: 366223
2019-07-16 15:57:12 +00:00
Matt Arsenault 58426a3707 AMDGPU: Serialize mode from MachineFunctionInfo
llvm-svn: 365653
2019-07-10 16:09:26 +00:00
Matt Arsenault e7e23e3e91 AMDGPU: Make AMDGPUPerfHintAnalysis an SCC pass
Add a string attribute instead of directly setting
MachineFunctionInfo. This avoids trying to get the analysis in the
MachineFunctionInfo in a way that doesn't work with the new pass
manager.

This will also avoid re-visiting the call graph for every single
function.

llvm-svn: 365241
2019-07-05 20:26:13 +00:00
Matt Arsenault 5b0922fe1f AMDGPU: Add pass to lower SGPR spills
This is split out from my patches to split register allocation into a
separate SGPR and VGPR phase, and has some parts that aren't yet used
(like maintaining LiveIntervals).

This simplifies making the frame pointer register callee saved. As it
is now, the code to determine callee saves needs to predict all the
possible SGPR spills and how many callee saved VGPRs are needed. By
handling this before PrologEpilogInserter, it's possible to just check
the spill objects that already exist.

Change-Id: I29e6df4034afcf949e06f8ef44206acb94696f04
llvm-svn: 365095
2019-07-03 23:32:29 +00:00
Michael Liao 80177ca5a9 [AMDGPU] Enable serializing of argument info.
Summary:
- Support serialization of all arguments in machine function info. This
  enables fabricating MIR tests depending on argument info.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64096

llvm-svn: 364995
2019-07-03 02:00:21 +00:00
Alexander Timofeev 2ce560f029 [AMDGPU] LCSSA pass added in preISel. Uniform values defined in the divergent loop and used outside
Differential Revision: https://reviews.llvm.org/D63953

Reviewers: rampitec, nhaehnle, arsenm
llvm-svn: 364950
2019-07-02 17:59:44 +00:00
Matt Arsenault 9cac4e6d14 Rename ExpandISelPseudo->FinalizeISel, delay register reservation
This allows targets to make more decisions about reserved registers
after isel. For example, now it should be certain there are calls or
stack objects in the frame or not, which could have been introduced by
legalization.

Patch by Matthias Braun

llvm-svn: 363757
2019-06-19 00:25:39 +00:00
Stanislav Mekhanoshin 3138278287 [AMDGPU] Propagate function attributes thru bitcasts
AMDGPUPropagateAttributes will not work on function bitcatsts,
so move AMDGPUFixFunctionBitcasts before it.

Differential Revision: https://reviews.llvm.org/D63455

llvm-svn: 363614
2019-06-17 20:42:48 +00:00
Stanislav Mekhanoshin a9191c8492 [AMDGPU] gfx1010 wavefrontsize intrinsic folding
Differential Revision: https://reviews.llvm.org/D63206

llvm-svn: 363588
2019-06-17 17:57:50 +00:00
Stanislav Mekhanoshin ad04e7ad42 [AMDGPU] Pass to propagate ABI attributes from kernels to the functions
The pass works in two modes:

Mode 1: Just set attributes starting from kernels. This can work at
the very beginning of opt and llc pipeline, but cannot clone functions
because it must be a function pass.

Mode 2: Actually clone functions for new attributes. This can only work
after all function passes in the opt pipeline because it has to be a
module pass.

Differential Revision: https://reviews.llvm.org/D63208

llvm-svn: 363586
2019-06-17 17:47:28 +00:00
Tom Stellard 4b0b26199b Revert CMake: Make most target symbols hidden by default
This reverts r362990 (git commit 374571301d)

This was causing linker warnings on Darwin:

ld: warning: direct access in function 'llvm::initializeEvexToVexInstPassPass(llvm::PassRegistry&)'
from file '../../lib/libLLVMX86CodeGen.a(X86EvexToVex.cpp.o)' to global weak symbol
'void std::__1::__call_once_proxy<std::__1::tuple<void* (&)(llvm::PassRegistry&),
std::__1::reference_wrapper<llvm::PassRegistry>&&> >(void*)' from file '../../lib/libLLVMCore.a(Verifier.cpp.o)'
means the weak symbol cannot be overridden at runtime. This was likely caused by different translation
units being compiled with different visibility settings.

llvm-svn: 363028
2019-06-11 03:21:13 +00:00
Tom Stellard 374571301d CMake: Make most target symbols hidden by default
Summary:
For builds with LLVM_BUILD_LLVM_DYLIB=ON and BUILD_SHARED_LIBS=OFF
this change makes all symbols in the target specific libraries hidden
by default.

A new macro called LLVM_EXTERNAL_VISIBILITY has been added to mark symbols in these
libraries public, which is mainly needed for the definitions of the
LLVMInitialize* functions.

This patch reduces the number of public symbols in libLLVM.so by about
25%.  This should improve load times for the dynamic library and also
make abi checker tools, like abidiff require less memory when analyzing
libLLVM.so

One side-effect of this change is that for builds with
LLVM_BUILD_LLVM_DYLIB=ON and LLVM_LINK_LLVM_DYLIB=ON some unittests that
access symbols that are no longer public will need to be statically linked.

Before and after public symbol counts (using gcc 8.2.1, ld.bfd 2.31.1):
nm before/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
36221
nm after/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
26278

Reviewers: chandlerc, beanz, mgorny, rnk, hans

Reviewed By: rnk, hans

Subscribers: Jim, hiraditya, michaelplatings, chapuni, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, kristina, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D54439

llvm-svn: 362990
2019-06-10 22:12:56 +00:00
Richard Trieu 8ce2ee9d56 [AMDGPU] Create a TargetInfo header. NFC
Move the declarations of getThe<Name>Target() functions into a new header in
TargetInfo and make users of these functions include this new header.
This fixes a layering problem.

llvm-svn: 360713
2019-05-14 21:54:37 +00:00
Stanislav Mekhanoshin 3b7925f035 [AMDGPU] gfx1010 GCNRegBankReassign pass
Reassign registers to reduce register bank conflicts.

Differential Revision: https://reviews.llvm.org/D61344

llvm-svn: 359704
2019-05-01 16:49:31 +00:00
Stanislav Mekhanoshin c29d491596 [AMDGPU] gfx1010 GCNNSAReassign pass
Convert NSA into non-NSA images.

Differential Revision: https://reviews.llvm.org/D61341

llvm-svn: 359700
2019-05-01 16:40:49 +00:00
Amara Emerson d189680baa [GlobalISel] Introduce a CSEConfigBase class to allow targets to define their own CSE configs.
Because CodeGen can't depend on GlobalISel, we need a way to encapsulate the CSE
configs that can be passed between TargetPassConfig and the targets' custom
pass configs. This CSEConfigBase allows targets to create custom CSE configs
which is then used by the GISel passes for the CSEMIRBuilder.

This support will be used in a follow up commit to allow constant-only CSE for
-O0 compiles in D60580.

llvm-svn: 358368
2019-04-15 04:53:46 +00:00
Nikita Popov 3db93ac5d6 Reapply [ValueTracking] Support min/max selects in computeConstantRange()
Add support for min/max flavor selects in computeConstantRange(),
which allows us to fold comparisons of a min/max against a constant
in InstSimplify. This fixes an infinite InstCombine loop, with the
test case taken from D59378.

Relative to the previous iteration, this contains some adjustments for
AMDGPU med3 tests: The AMDGPU target runs InstSimplify prior to codegen,
which ends up constant folding some existing med3 tests after this
change. To preserve these tests a hidden -amdgpu-scalar-ir-passes option
is added, which allows disabling scalar IR passes (that use InstSimplify)
for testing purposes.

Differential Revision: https://reviews.llvm.org/D59506

llvm-svn: 357870
2019-04-07 17:22:16 +00:00
Stanislav Mekhanoshin c8f78f8dd3 [AMDGPU] Add MachineDCE pass after RenameIndependentSubregs
Detect dead lanes can create some dead defs. Then RenameIndependentSubregs
will break a REG_SEQUENCE which may use these dead defs. At this point
a dead instruction can be removed but we do not run a DCE anymore.

MachineDCE was only running before live variable analysis. The patch
adds a mean to preserve LiveIntervals and SlotIndexes in case it works
past this.

Differential Revision: https://reviews.llvm.org/D59626

llvm-svn: 357805
2019-04-05 20:11:32 +00:00
Neil Henning 0a30f33ce2 [AMDGPU] Pre-allocate WWM registers to reduce VGPR pressure.
This change incorporates an effort by Connor Abbot to change how we deal
with WWM operations potentially trashing valid values in inactive lanes.

Previously, the SIFixWWMLiveness pass would work out which registers
were being trashed within WWM regions, and ensure that the register
allocator did not have any values it was depending on resident in those
registers if the WWM section would trash them. This worked perfectly
well, but would cause sometimes severe register pressure when the WWM
section resided before divergent control flow (or at least that is where
I mostly observed it).

This fix instead runs through the WWM sections and pre allocates some
registers for WWM. It then reserves these registers so that the register
allocator cannot use them. This results in a significant register
saving on some WWM shaders I'm working with (130 -> 104 VGPRs, with just
this change!).

Differential Revision: https://reviews.llvm.org/D59295

llvm-svn: 357400
2019-04-01 15:19:52 +00:00
Matt Arsenault 4d47ac3b30 AMDGPU: Add additional MIR tests for exec mask optimizations
Also includes one example of how this transform is unsound. This isn't
verifying the copies are used in the control flow intrinisic patterns.

Also add option to disable exec mask opt pass. Since this pass is
unsound, it may be useful to turn it off until it is fixed.

llvm-svn: 357091
2019-03-27 16:58:30 +00:00
Matt Arsenault cf55a657f0 CodeGen: Refactor regallocator command line and target selection
This will allow targets more flexibility to replace the
register allocator core passes. In a future commit,
AMDGPU will run the core register assignment passes
twice, and will also want to disallow using the
standard -regalloc option.

llvm-svn: 356506
2019-03-19 19:33:12 +00:00
Neil Henning 523dab0788 [AMDGPU] Add an experimental buffer fat pointer address space.
Add an experimental buffer fat pointer address space that is currently
unhandled in the backend. This commit reserves address space 7 as a
non-integral pointer repsenting the 160-bit fat pointer (128-bit buffer
descriptor + 32-bit offset) that is heavily used in graphics workloads
using the AMDGPU backend.

Differential Revision: https://reviews.llvm.org/D58957

llvm-svn: 356373
2019-03-18 14:44:28 +00:00
Matt Arsenault e0c1f9e76d AMDGPU: Partially fix default device for HSA
There are a few different issues, mostly stemming from using
generation based checks for anything instead of subtarget
features. Stop adding flat-address-space as a feature for HSA, as it
should only be a device property. This was incorrectly allowing flat
instructions to select for SI.

Increase the default generation for HSA to avoid the encoding error
when emitting objects. This has some other side effects from various
checks which probably should be separate subtarget features (in the
cost model and for dealing with the DS offset folding issue).

Partial fix for bug 41070. It should probably be an error to try using
amdhsa without flat support.

llvm-svn: 356347
2019-03-17 21:31:35 +00:00
Matt Arsenault bc6d07ca46 MIR: Allow targets to serialize MachineFunctionInfo
This has been a very painful missing feature that has made producing
reduced testcases difficult. In particular the various registers
determined for stack access during function lowering were necessary to
avoid undefined register errors in a large percentage of
cases. Implement a subset of the important fields that need to be
preserved for AMDGPU.

Most of the changes are to support targets parsing register fields and
properly reporting errors. The biggest sort-of bug remaining is for
fields that can be initialized from the IR section will be overwritten
by a default initialized machineFunctionInfo section. Another
remaining bug is the machineFunctionInfo section is still printed even
if empty.

llvm-svn: 356215
2019-03-14 22:54:43 +00:00
Aakanksha Patil c56d2afc63 AMDGPU: Handle "uniform-work-group-size" attribute (fix for RADV)
A previous patch for "uniform-work-group-size" attribute was found to break
some RADV and possibly radeon SI tests and had to be retracted.
This patch fixes that.

Differential Revision: http://reviews.llvm.org/D58993

llvm-svn: 355574
2019-03-07 00:54:04 +00:00
Matt Arsenault 09a09ef8b7 AMDGPU: Fix typo
llvm-svn: 355056
2019-02-28 00:52:33 +00:00
Matt Arsenault 5d567dc137 AMDGPU: Enable function calls by default
Fixes some crashes on illegal call situations which are unfortunately
still valid IR.

llvm-svn: 355051
2019-02-28 00:40:32 +00:00
Matt Arsenault aa6fb4c45e AMDGPU: Remove debugger related subtarget features
As far as I know these aren't needed anymore.

llvm-svn: 354634
2019-02-21 23:27:46 +00:00
Valery Pykhtin ded96df01e [AMDGPU] Enable DPP combiner pass by default.
Related revisions: https://reviews.llvm.org/D55444, https://reviews.llvm.org/D55314

llvm-svn: 353691
2019-02-11 11:15:03 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
David Stuttard f77079f892 [AMDGPU] Add support for TFE/LWE in image intrinsics. 2nd try
TFE and LWE support requires extra result registers that are written in the
event of a failure in order to detect that failure case.
The specific use-case that initiated these changes is sparse texture support.

This means that if image intrinsics are used with either option turned on, the
programmer must ensure that the return type can contain all of the expected
results. This can result in redundant registers since the vector size must be a
power-of-2.

This change takes roughly 6 parts:
1. Modify the instruction defs in tablegen to add new instruction variants that
can accomodate the extra return values.
2. Updates to lowerImage in SIISelLowering.cpp to accomodate setting TFE or LWE
(where the bulk of the work for these instruction types is now done)
3. Extra verification code to catch cases where intrinsics have been used but
insufficient return registers are used.
4. Modification to the adjustWritemask optimisation to account for TFE/LWE being
enabled (requires extra registers to be maintained for error return value).
5. An extra pass to zero initialize the error value return - this is because if
the error does not occur, the register is not written and thus must be zeroed
before use. Also added a new (on by default) option to ensure ALL return values
are zero-initialized that is required for sparse texture support.
6. Disable the inst_combine optimization in the presence of tfe/lwe (later TODO
for this to re-enable and handle correctly).

There's an additional fix now to avoid a dmask=0

For an image intrinsic with tfe where all result channels except tfe
were unused, I was getting an image instruction with dmask=0 and only a
single vgpr result for tfe. That is incorrect because the hardware
assumes there is at least one vgpr result, plus the one for tfe.

Fixed by forcing dmask to 1, which gives the desired two vgpr result
with tfe in the second one.

The TFE or LWE result is returned from the intrinsics using an aggregate
type. Look in the test code provided to see how this works, but in essence IR
code to invoke the intrinsic looks as follows:

%v = call {<4 x float>,i32} @llvm.amdgcn.image.load.1d.v4f32i32.i32(i32 15,
                                      i32 %s, <8 x i32> %rsrc, i32 1, i32 0)
%v.vec = extractvalue {<4 x float>, i32} %v, 0
%v.err = extractvalue {<4 x float>, i32} %v, 1

This re-submit of the change also includes a slight modification in
SIISelLowering.cpp to work-around a compiler bug for the powerpc_le
platform that caused a buildbot failure on a previous submission.

Differential revision: https://reviews.llvm.org/D48826

Change-Id: If222bc03642e76cf98059a6bef5d5bffeda38dda


Work around for ppcle compiler bug

Change-Id: Ie284cf24b2271215be1b9dc95b485fd15000e32b
llvm-svn: 351054
2019-01-14 11:55:24 +00:00
Aakanksha Patil bc568766b2 Revert r348971: [AMDGPU] Support for "uniform-work-group-size" attribute
This patch breaks RADV (and probably RadeonSI as well)

llvm-svn: 349084
2018-12-13 21:23:12 +00:00
Aakanksha Patil 729309cc89 [AMDGPU] Support for "uniform-work-group-size" attribute
Updated the annotate-kernel-features pass to support the propagation of uniform-work-group attribute from the kernel to the called functions. Once this pass is run, all kernels, even the ones which initially did not have the attribute, will be able to indicate weather or not they have uniform work group size depending on the value of the attribute. 

Differential Revision: https://reviews.llvm.org/D50200

llvm-svn: 348971
2018-12-12 20:49:17 +00:00
Tim Corringham 4c4d2fe280 [AMDGPU] Add new Mode Register pass
A new pass to manage the Mode register.

Currently this just manages the floating point double precision
rounding requirements, but is intended to be easily extended to
encompass all Mode register settings.

The immediate motivation comes from the requirement to use the
round-to-zero rounding mode for the 16 bit interpolation
instructions, where the rounding mode setting is shared between
16 and 64 bit operations.

llvm-svn: 348754
2018-12-10 12:06:10 +00:00
David Green ca29c271d2 [Targets] Add errors for tiny and kernel codemodel on targets that don't support them
Adds fatal errors for any target that does not support the Tiny or Kernel
codemodels by rejigging the getEffectiveCodeModel calls.

Differential Revision: https://reviews.llvm.org/D50141

llvm-svn: 348585
2018-12-07 12:10:23 +00:00
Valery Pykhtin f479fbba5f [AMDGPU] Partial revert of rL348371: Turn on the DPP combiner by default
Turn the combiner back off as there're failures until the issue is fixed.

Differential revision: https://reviews.llvm.org/D55314

llvm-svn: 348487
2018-12-06 14:20:02 +00:00
Valery Pykhtin 5b4db77b13 [AMDGPU]: Turn on the DPP combiner by default
Differential revision: https://reviews.llvm.org/D55314

llvm-svn: 348371
2018-12-05 15:21:17 +00:00
Valery Pykhtin 3d9afa273f [AMDGPU] Combine DPP mov with use instructions (VOP1/2/3)
Introduces DPP pseudo instructions and the pass that combines DPP mov with subsequent uses.

Differential revision: https://reviews.llvm.org/D53762

llvm-svn: 347993
2018-11-30 14:21:56 +00:00
David Stuttard c6603861d8 Revert r347871 "Fix: Add support for TFE/LWE in image intrinsic"
Also revert fix r347876

One of the buildbots was reporting a failure in some relevant tests that I can't
repro or explain at present, so reverting until I can isolate.

llvm-svn: 347911
2018-11-29 20:14:17 +00:00
David Stuttard de02e4b1cc Add support for TFE/LWE in image intrinsics
TFE and LWE support requires extra result registers that are written in the
event of a failure in order to detect that failure case.
The specific use-case that initiated these changes is sparse texture support.

This means that if image intrinsics are used with either option turned on, the
programmer must ensure that the return type can contain all of the expected
results. This can result in redundant registers since the vector size must be a
power-of-2.

This change takes roughly 6 parts:
1. Modify the instruction defs in tablegen to add new instruction variants that
can accomodate the extra return values.
2. Updates to lowerImage in SIISelLowering.cpp to accomodate setting TFE or LWE
(where the bulk of the work for these instruction types is now done)
3. Extra verification code to catch cases where intrinsics have been used but
insufficient return registers are used.
4. Modification to the adjustWritemask optimisation to account for TFE/LWE being
enabled (requires extra registers to be maintained for error return value).
5. An extra pass to zero initialize the error value return - this is because if
the error does not occur, the register is not written and thus must be zeroed
before use. Also added a new (on by default) option to ensure ALL return values
are zero-initialized that is required for sparse texture support.
6. Disable the inst_combine optimization in the presence of tfe/lwe (later TODO
for this to re-enable and handle correctly).

There's an additional fix now to avoid a dmask=0

For an image intrinsic with tfe where all result channels except tfe
were unused, I was getting an image instruction with dmask=0 and only a
single vgpr result for tfe. That is incorrect because the hardware
assumes there is at least one vgpr result, plus the one for tfe.

Fixed by forcing dmask to 1, which gives the desired two vgpr result
with tfe in the second one.

The TFE or LWE result is returned from the intrinsics using an aggregate
type. Look in the test code provided to see how this works, but in essence IR
code to invoke the intrinsic looks as follows:

%v = call {<4 x float>,i32} @llvm.amdgcn.image.load.1d.v4f32i32.i32(i32 15,
                                      i32 %s, <8 x i32> %rsrc, i32 1, i32 0)
%v.vec = extractvalue {<4 x float>, i32} %v, 0
%v.err = extractvalue {<4 x float>, i32} %v, 1

Differential revision: https://reviews.llvm.org/D48826

Change-Id: If222bc03642e76cf98059a6bef5d5bffeda38dda
llvm-svn: 347871
2018-11-29 15:21:13 +00:00
Matt Arsenault 105fc1a5f3 AMDGPU: Don't optimize exec masks at -O0
llvm-svn: 347573
2018-11-26 17:02:02 +00:00
Ron Lieberman cac749ac88 [AMDGPU] Add FixupVectorISel pass, currently Supports SREGs in GLOBAL LD/ST
Add a pass to fixup various vector ISel issues.
Currently we handle converting GLOBAL_{LOAD|STORE}_*
and GLOBAL_Atomic_* instructions into their _SADDR variants.
This involves feeding the sreg into the saddr field of the new instruction.

llvm-svn: 347008
2018-11-16 01:13:34 +00:00
Matt Arsenault 8ba740a5a8 Allow subclassing ExternalAA
This allows testing AMDGPU alias analysis like any
other alias analysis pass. This fixes the existing
test pointlessly running opt -O3 when it really
just wants to run the one analysis.

Before there was no way to test this using -aa-eval
with opt, since the default constructed pass
is run. The wrapper subclass allows the
default constructor to pass the necessary callback.

llvm-svn: 346353
2018-11-07 20:26:42 +00:00
Nicolai Haehnle 814abb59df AMDGPU: Rewrite SILowerI1Copies to always stay on SALU
Summary:
Instead of writing boolean values temporarily into 32-bit VGPRs
if they are involved in PHIs or are observed from outside a loop,
we use bitwise masking operations to combine lane masks in a way
that is consistent with wave control flow.

Move SIFixSGPRCopies to before this pass, since that pass
incorrectly attempts to move SGPR phis to VGPRs.

This should recover most of the code quality that was lost with
the bug fix in "AMDGPU: Remove PHI loop condition optimization".

There are still some relevant cases where code quality could be
improved, in particular:

- We often introduce redundant masks with EXEC. Ideally, we'd
  have a generic computeKnownBits-like analysis to determine
  whether masks are already masked by EXEC, so we can avoid this
  masking both here and when lowering uniform control flow.

- The criterion we use to determine whether a def is observed
  from outside a loop is conservative: it doesn't check whether
  (loop) branch conditions are uniform.

Change-Id: Ibabdb373a7510e426b90deef00f5e16c5d56e64b

Reviewers: arsenm, rampitec, tpr

Subscribers: kzhuravl, jvesely, wdng, mgorny, yaxunl, dstuttard, t-tye, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D53496

llvm-svn: 345719
2018-10-31 13:27:08 +00:00
Scott Linder 11ef7984b0 [AMDGPU] Add a pass to promote bitcast calls
AMDGPU currently only supports direct calls, but at lower optimisation levels it
fails to lower statically direct calls which appear indirect due to a bitcast.

Add a pass to visit all CallSites and use CallPromotionUtils to "devirtualize"
calls.

Differential Revision: https://reviews.llvm.org/D52741

llvm-svn: 345382
2018-10-26 13:18:36 +00:00
Neil Henning 6641657453 [AMDGPU] Add an AMDGPU specific atomic optimizer.
This commit adds a new IR level pass to the AMDGPU backend to perform
atomic optimizations. It works by:

- Running through a function and finding atomicrmw add/sub or uses of
  the atomic buffer intrinsics for add/sub.
- If all arguments except the value to be added/subtracted are uniform,
  record the value to be optimized.
- Run through the atomic operations we can optimize and, depending on
  whether the value is uniform/divergent use wavefront wide operations
  (DPP in the divergent case) to calculate the total amount to be
  atomically added/subtracted.
- Then let only a single lane of each wavefront perform the atomic
  operation, reducing the total number of atomic operations in flight.
- Lastly we recombine the result from the single lane to each lane of
  the wavefront, and calculate our individual lanes offset into the
  final result.

Differential Revision: https://reviews.llvm.org/D51969

llvm-svn: 343973
2018-10-08 15:49:19 +00:00