Commit Graph

239 Commits

Author SHA1 Message Date
Johannes Doerfert b4a7559844 [OpenMP][FIX] Replace ICVs only with values valid at the getter position
While we might know the value if an ICV at a getter position it is not
always clear that we can simply use it. Verify the value is valid first
to avoid invalid IR.

Fixes #53300.
2022-01-19 18:40:13 -06:00
Eli Friedman 86cdff0e21 [OpenMPOpt] Use SetVector to store list of kernels.
Fixes test failures on reverse-iteration buildbot.
2022-01-19 13:55:32 -08:00
Simon Pilgrim 274359cf09 [OpenMPOpt] Use cast<> instead of dyn_cast<> to avoid dereference of nullptr. NFC 2022-01-08 13:47:35 +00:00
Kazu Hirata 2aed08131d [llvm] Use true/false instead of 1/0 (NFC)
Identified with modernize-use-bool-literals.
2022-01-07 00:39:14 -08:00
Johannes Doerfert 944aa0421c Reapply "[OpenMP][NFCI] Embed the source location string size in the ident_t"
This reverts commit 73ece231ee and
reapplies 7bfcdbcbf3 with mlir changes.
Also reverts commit 423ba12971 and
includes the unit test changes of
16da214004.
2021-12-29 01:10:38 -06:00
Mehdi Amini 73ece231ee Revert "[OpenMP][NFCI] Embed the source location string size in the ident_t"
This reverts commit 7bfcdbcbf3.
Broke MLIR build
2021-12-29 06:57:36 +00:00
Johannes Doerfert 3e0c512ce6 [OpenMP] Simplify all stores in the device code
Similar to loads, we want to be aggressive when it comes to store
simplification. Not everything in LLVM handles dead stores well when
address space casts are involved, we can simply ask the Attributor to do
it for us though.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D109998
2021-12-29 00:19:38 -06:00
Johannes Doerfert 7bfcdbcbf3 [OpenMP][NFCI] Embed the source location string size in the ident_t
One of the unused ident_t fields now holds the size of the string
(=const char *) field so we have an easier time dealing with those
in the future.

Differential Revision: https://reviews.llvm.org/D113126
2021-12-28 23:53:29 -06:00
Johannes Doerfert 9f04a0ea43 [OpenMP][FIX] Make AAExecutionDomain deterministic 2021-12-28 23:53:29 -06:00
Johannes Doerfert ba70f3a5d9 [OpenMP][FIX] Make heap2shared deterministic
Issue #52875 reported non-determinism, this is the first step to avoid
it. We iterate over MallocCalls so we should keep the order stable.
2021-12-28 23:53:28 -06:00
Johannes Doerfert 7de5da2a67 [OpenMP][NFC] Move address space enum into OMPConstants header 2021-12-28 23:53:28 -06:00
Joseph Huber 6e220296d7 [OpenMP] Use alignment information in HeapToShared
This patch uses the return alignment attribute now present in the
`__kmpc_alloc_shared` runtime call to set the alignment of the shared
memory global created to replace it.

Depends on D115971

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D116319
2021-12-27 16:58:27 -05:00
Joseph Huber 744aa09f52 [OpenMP] Make reduction functions SPMD compatible
Reduction functions were guarded before which was wrong, these are SPMD
compatible.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D115159
2021-12-06 12:32:02 -05:00
Joseph Huber 9ea5b97203 [OpenMP][FIX] Invalidate the SPMDCompatibilityTracker explicitly
Before SPMDzation it was sufficient to add an incompatible instruction
to the SPMDCompatibilityTracker. However, now adding instructions means
they need guarding. As calls cannot be guarded in general we need to
explicitly prevent SPMD mode.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D115158
2021-12-06 12:31:57 -05:00
Joseph Huber 058c312a44 [OpenMP][FIX] SPMDzation guarding needs to account for all reaching kernels
If two reaching kernels disagree on the execution mode we cannot guard a
function right now. Ensure we do not as we otherwise will cause a
deadlock.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D114866
2021-12-01 11:44:32 -05:00
Joseph Huber 7986a5f23e [OpenMP] Add RTL function to externalization RAII
This patch adds the `__kmpc_get_warp_size` OpenMP RTL function to the
externalization RAII struct. This was getting optimized out and then
being replaced with an undefined value once added back in, causing bugs
for complex reductions.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D114802
2021-11-30 10:19:06 -05:00
Kazu Hirata d243cbf8ea [llvm] Use isa instead of dyn_cast (NFC) 2021-11-14 19:40:46 -08:00
Joel E. Denny c9dfe322ee [OpenMP] Fix main thread barrier for Pascal and amdgpu
Fixes what's left of https://bugs.llvm.org/show_bug.cgi?id=51781.

Reviewed By: jdoerfert, JonChesterfield, tianshilei1992

Differential Revision: https://reviews.llvm.org/D113602
2021-11-12 11:18:45 -05:00
Joseph Huber e52937eba0 [OpenMP] Use AAAssumptionInfo to get assumptions in OpenMPOpt
This patch uses the abstract attributor introduced in D111054 to get the
assumption values instead of the `hasAssumption` function. This also
calls it so assumption information should propagate throug the device
where applicabile.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D111445
2021-11-09 17:39:21 -05:00
Johannes Doerfert d61aac76bf [OpenMP][FIX] Do not signal SPMD-mode but then keep generic-mode
If we assume SPMD-mode during the fixpoint iteration we have to execute
the kernel in SPMD-mode. If we change our mind during manifest there is
the chance of a mismatch between the simplification, e.g., of
`__kmpc_is_spmd_exec_mode` calls, and the execution mode. This problem
was introduced in D109438.

This patch is compromise to resolve the problem purely in OpenMP-opt
while trying to keep the benefits of D109438 around. This might not
always work, see `get_hardware_num_threads_in_block_fold` but it often
does. At the same time we do keep value specialization and execution
mode in sync.

Proper solutions to this problem should be considered. I believe a new
execution mode is the easiest way forward (Singleton-SPMD).
Alternatively, SPMD-mode execution can be used with a way to provide a
new thread_limit (here 1) to the runtime. This is more general and could
be useful if we see `num_threads` clauses or workshared loops with small
trip counts in the kernel. In either proposal we need to disable the
guarding for the kernel (which was the motivation for D109438).

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D112894
2021-11-02 23:22:04 -05:00
Johannes Doerfert 73720c8059 [OpenMP][FIX] Introduce and use a simple generic-mode barrier
Before we had aligned barriers the `__kmpc_barrier_simple_spmd` was
OK to be used in the custom state machine. Now that SPMD barriers are
assumed to be aligned we need to use a "generic" barrier in places
that are not aligned.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D112893
2021-11-02 23:22:01 -05:00
Johannes Doerfert e6e440ae5f [OpenMP][FIX] Ensure guarding uses proper global name
Global symbols cannot have any name so we need to sanitize the string
first. Also remove an assertion that is not actually necessary nor
true in general.

Reviewed By: ggeorgakoudis

Differential Revision: https://reviews.llvm.org/D112892
2021-11-02 23:21:53 -05:00
Kazu Hirata 9800731367 [Target, Transforms] Use predecessors instead of pred_begin and pred_end (NFC) 2021-10-24 17:35:35 -07:00
Joseph Huber f074a6a041 [OpenMP] Add options to change Attributor max iterations in OpenMPOpt
This patch adds a new command line option `openmp-opt-max-iterations`
that controls the maximum number of iterations the attributor will run
for when compiling OpenMP target device code. This patch also adds a
remark to indicate when the attributor failed because it did not run
for enough iterations.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110749
2021-10-04 09:39:04 -04:00
Kazu Hirata 4f0225f6d2 [Transforms] Migrate from getNumArgOperands to arg_size (NFC)
Note that getNumArgOperands is considered a legacy name.  See
llvm/include/llvm/IR/InstrTypes.h for details.
2021-10-01 09:57:40 -07:00
Joseph Huber c11ebfea6d [OpenMP][NFC] Fix linting messages in OpenMPOpt
Summary:
This patch addresses some linting messages I keep getting in my editor
when working on OpenMPOpt.
2021-09-29 16:07:33 -04:00
Joseph Huber 87ce7e65f2 [OpenMP] Add missing distribute definitions to AAKernelInfo
Summary:
The RTL functions added in https://reviews.llvm.org/D110429 were
mistakenly left out from the list of safe runtime calls in AAKernelInfo.
This patch adds them in.
2021-09-29 16:06:34 -04:00
Johannes Doerfert c6457dcae8 [OpenMP][FIX] Be more deliberate about invalidating the AAKernelInfo state
This patch fixes a problem when the AAKernelInfo state was invalidated,
e.g., due to `optnone` for a kernel, but not all parts indicated the
invalidation properly. We further eliminate most full state
invalidations as they should never be necessary.

Differential Revision: https://reviews.llvm.org/D109468
2021-09-23 00:04:30 -05:00
Johannes Doerfert 0a16c56010 [OpenMP][NFC] Improve debug output 2021-09-23 00:04:29 -05:00
Shilei Tian 423d34f74a [OpenMP][Offloading] Change `bool IsSPMD` to `int8_t Mode` in `__kmpc_target_init` and `__kmpc_target_deinit`
This is a follow-up of D110029, which uses bitset to indicate execution mode. This patches makes the changes in the function call.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110279
2021-09-22 17:16:41 -04:00
Shilei Tian ca999f7191 [OpenMP][Offloading] Use bitset to indicate execution mode instead of value
The execution mode of a kernel is stored in a global variable, whose value means:
- 0 - SPMD mode
- 1 - indicates generic mode
- 2 - SPMD mode execution with generic mode semantics

We are going to add support for SIMD execution mode. It will be come with another
execution mode, such as SIMD-generic mode. As a result, this value-based indicator
is not flexible.

This patch changes to bitset based solution to encode execution mode. Each
position is:
[0] - generic mode
[1] - SPMD mode
[2] - SIMD mode (will be added later)

In this way, `0x1` is generic mode, `0x2` is SPMD mode, and `0x3` is SPMD mode
execution with generic mode semantics. In the future after we add the support for
SIMD mode, `0b1xx` will be in SIMD mode.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110029
2021-09-22 11:40:52 -04:00
Joseph Huber 1cf86df883 [OpenMP] Make sure the Thread ID function is not removed
Summary:
The thread ID function was reintroduced in D110195, but could
potentially be removed by the optimizer. Make the function noinline to
preserve the call sites and add it to the externalization RAII so its
definition is not removed by the attributor.
2021-09-22 10:13:18 -04:00
Joseph Huber 27905eeb89 [Attributor] Change AAExecutionDomain to check intrinsic edges
The AAExecutionDomain instance checks if a BB is executed by the main
thread only. Currently, this only checks the `__kmpc_kernel_init` call
for generic regions to indicate the path taken by the main thread. In
the new runtime, we want to be able to detect basic blocks even in SPMD
mode. For this we enable it to check thread-ID intrinsics being compared
to zero as well.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D109849
2021-09-17 19:51:38 -04:00
Jon Chesterfield 71052ea1e3 [openmp] Apply code change from D109500 2021-09-13 18:33:53 +01:00
Jon Chesterfield bfcf979978 Revert "[openmp] Fix 51647, corrupt bitcode on amdgpu"
This reverts commit d5c049a3f6.
Going to re-commit it in pieces for easier application to 13
2021-09-13 18:25:07 +01:00
dpalermo d5c049a3f6 [openmp] Fix 51647, corrupt bitcode on amdgpu
Patch by @dpalermo

The corrupt bitcode reported in https://bugs.llvm.org/show_bug.cgi?id=51647 seems to be a result of a later pass changing the workfn variable to addrspace(5) (thread private, on the stack). That seems reasonable for an alloca without an address space so it's an open question why that can crash the bitcode reader.

This change puts it in the thread private address space to begin with which means whatever misfired further down the pipeline does not break it. That matches the codegen from clang where stack variables are always annotated (5) and then addrspace cast prior to following use.

This therefore patches around whatever unsuccessfully moved the alloca variable to addrspace(5). That solves the problem of openmp opt producing code that crashes the bitcode reader. It should be possible to create a minimal repro for the underlying bug based on some handwritten IR that uses an alloca in a generic address space.

Reviewed By: ronlieb, jdoerfert, dpalermo-phab

Differential Revision: https://reviews.llvm.org/D109500
2021-09-13 15:24:48 +01:00
Joseph Huber 7eb899cbcd [OpenMP] Add more verbose remarks for runtime folding
We peform runtime folding, but do not currently emit remarks when it is
performed. This is because it comes from the runtime library and is
beyond the users control. However, people may still wish to view  this
and similar information easily, so we can enable this behaviour using a
special flag to enable verbose remarks.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D109627
2021-09-10 17:36:06 -04:00
Johannes Doerfert 99ea8ac9f1 Reapply "[OpenMP] Group side-effects to improve guarding efficiency"
This reapplies ca134c3963, effectively
reverting commit d2f206e0af.

Minor test changes to make the test pass.
2021-09-10 15:22:57 -05:00
Joseph Huber 9e2fc0ba37 [OpenMP] Check OpenMP assumptions on call-sites as well
This patch adds functionality to check assumption attributes on call
sites as well.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D109376
2021-09-10 14:52:47 -04:00
Johannes Doerfert d2f206e0af Revert "[OpenMP] Group side-effects to improve guarding efficiency"
This reverts commit ca134c3963.

There seems to be a problem with the tests, investigating now:
  https://lab.llvm.org/buildbot/#/builders/61/builds/14574
2021-09-10 12:24:00 -05:00
Johannes Doerfert ca134c3963 [OpenMP] Group side-effects to improve guarding efficiency
When we guard side-effects as part of SPMDzation we do it for
consecutive instructions that need guarding. This patch will try to
reorder guarded side-effects in a block to decrease the number of
guarded regions we need. It does not use any smarts, e.g., alias
analysis, to move side-effects over non-interfering reads. Instead,
it only moves side-effects downwards to the next guarded side-effect
if there was nothing in between that could have possibly be affected.

Reviewed By: ggeorgakoudis

Differential Revision: https://reviews.llvm.org/D109070
2021-09-10 12:08:48 -05:00
Kazu Hirata 92c9ff6d5f [IR, Transforms] Use arg_empty (NFC) 2021-09-09 08:50:10 -07:00
Joseph Huber 6b9a3ec3a2 [OpenMP] Do not SPMDize generic regions with no parallel
This patch changes SPMDization to not trigger for regions with no
parallelism. Otherwise, this will introduce unnecessary barriers that
will slow the single-threaded region down.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D109438
2021-09-08 14:33:15 -04:00
Joseph Huber 29a74a3915 [OpenMP] Add an option to always inline OpenMP device functions.
Performance on GPU targets can be highly variable, sometimes inlining
everything hurts performance and sometimes it greatly improves it. Add
an option to toggle this behaviour to better investigate it.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D109014
2021-08-31 18:48:30 -04:00
Joseph Huber 13d8f000d7 [OpenMP][NFC] Improve debug message for shared memory
Summary:
Make the debug message for HeapToShared more helpful by showing the
actual call.
2021-08-18 11:56:09 -04:00
Joseph Huber 58f9326487 [OpenMP] Change AAKernelInfo to ignore non-kernels
Currently, AAKernelInfo will fail on an assertion if we attempt to run
it on a kernel without the init / deinit runtime calls. However, this
occurs for global constructors on the device. This will cause OpenMPOpt
to crash whenever global constructors are present. This patch removes
this assertion and just gives up instead.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D108258
2021-08-18 11:24:29 -04:00
Joseph Huber 339aa76526 [OpenMP][NFC] Add option to print module after OpenMPOpt for debugging
This patch adds an extra option to print the module after running one of
the OpenMPOpt passes if debugging is enabled. This makes it much easier
to inspect the effects of this pass when doing debugging.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D108146
2021-08-17 12:46:10 -04:00
Arthur Eubanks 80ea2bb574 [NFC] Rename AttributeList::getParam/Ret/FnAttributes() -> get*Attributes()
This is more consistent with similar methods.
2021-08-13 11:16:52 -07:00
Giorgis Georgakoudis 60e643fe05 [OpenMP][Fix] Fix disable spmdization option
Besides SPMDization, other analysis and optimization for original, frontend-generated SPMD regions uses information from the AAKernelInfoFunction attribute. This fix makes sure disabling SPMDization through the corresponding option applies only to generic mode regions, which should not be SPMDized, while it leaves unaffected the attribute state of original SPMD regions.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D108001
2021-08-12 17:59:14 -07:00
Johannes Doerfert e0c5d83a92 [OpenMP][FIX] Disabled optimizations have to be made known
To avoid simplification with wrong constants we need to make sure we
know that we won't perform specific optimizations based on the users
request. The non-SPMDzation and non-CustomStateMachine flags did only
prevent the final transformation but allowed to value simplification
to go ahead.

Differential Revision: https://reviews.llvm.org/D107862
2021-08-11 00:49:53 -05:00
Giorgis Georgakoudis 29a3e3dd7b [OpenMPOpt] Expand SPMDization with guarding for target parallel regions
This patch expands SPMDization (converting generic execution mode to SPMD for target regions) by guarding code regions that should be executed only by the main thread. Specifically, it generates guarded regions, which only the main thread executes, and the synchronization with worker threads using simple barriers. For correctness, the patch aborts SPMDization for target regions if the same code executes in a parallel region, thus must be not be guarded. This check is implemented using the ParallelLevels AA.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D106892
2021-08-04 11:49:24 -07:00
Joseph Huber cd0dd8ece8 [OpenMP] Adding flags for disabling the following optimizations: Deglobalization SPMDization State machine rewrites Folding
This work provides four flags to disable four different sets of OpenMP optimizations. These flags take effect in llvm/lib/Transforms/IPO/OpenMPOpt.cpp and include the following:
 - openmp-opt-disable-deglobalization: Defaults to false, adding this flag sets the variable DisableOpenMPOptDeglobalization to true. This prevents AA registration for HeapToStack and HeapToShared.
 - openmp-opt-disable-spmdization: Defaults to false, adding this flag sets the variable DisableOpenMPOptSPMDization to true. This indicates a pessimistic fixpoint in changeToSPMDMode.
 - openmp-opt-disable-folding: Defaults to false, adding this flag sets the variable DisableOpenMPOptFolding to true. This indicates a pessimistic fixpoint in the attributor init for AAFoldRuntimeCall.
 - openmp-opt-disable-state-machine-rewrite: Defaults to false, adding this flag sets the variable DisableOpenMPOptStateMachineRewrite to true. This first prevents changes to the state machine in rewriteDeviceCodeStateMachine by returning before changes are made, and if a custom state machine is built in buildCustomStateMachine, stops by returning a pessimistic fixpoint.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D106802
2021-07-29 19:28:31 -04:00
Joseph Huber adbaa39dfc [Attributor] Change function internalization to not replace uses in internalized callers
The current implementation of function internalization creats a copy of each
function and replaces every use. This has the downside that the external
versions of the functions will call into the internalized versions of the
functions. This prevents them from being fully independent of eachother. This
patch replaces the current internalization scheme with a method that creates
all the copies of the functions intended to be internalized first and then
replaces the uses as long as their caller is not already internalized.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106931
2021-07-28 18:57:28 -04:00
Jose M Monsalve Diaz 5ab6aedda9 [OpenMP] Folding threadLimit and numThreads when single value in kernels
The device runtime contains several calls to `__kmpc_get_hardware_num_threads_in_block`
and `__kmpc_get_hardware_num_blocks`. If the thread_limit and the num_teams are constant,
these calls can be folded to the constant value.

In this patch we use the already introduced `AAFoldRuntimeCall` and the `NumTeams` and
`NumThreads` kernel attributes (to be introduced in a different patch) to fold these functions.
The code checks all the kernels, and if their attributes match, the functions are folded.

In the future we will explore specializing for multiple values of NumThreads and NumTeams.

Depends on D106390

Reviewed By: jdoerfert, JonChesterfield

Differential Revision: https://reviews.llvm.org/D106033
2021-07-27 21:47:12 -04:00
Johannes Doerfert 70b75f62fc [OpenMP] Try to simplify all loads in device code
Eliminating loads/stores in the device code is worth the extra effort,
especially for the new device runtime.

At the same time we do not compute AAExecutionDomain for non-device code
anymore, there is no point.

Differential Revision: https://reviews.llvm.org/D106845
2021-07-27 01:44:15 -05:00
Shilei Tian e97e0a4fad [AbstractAttributor] Fold __kmpc_parallel_level if possible
Similar to D105787, this patch tries to fold `__kmpc_parallel_level` if possible.
Note that `__kmpc_parallel_level` doesn't take activeness into consideration,
based on current `deviceRTLs`, its return value can be such as 0, 1, 2, instead
of 0, 129, 130, etc. that also indicate activeness.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106154
2021-07-26 22:46:19 -04:00
Johannes Doerfert be2b569646 [OpenMP] Run rewriteDeviceCodeStateMachine in the Module not CGSCC pass
While rewriteDeviceCodeStateMachine should probably be folded into
buildCustomStateMachine, we at least need the optimization to happen.
This was not reliably the case in the CGSCC pass but in the Module pass
it seems to work reliably.

This also ports a test to the new kernel encoding (target_init/deinit),
and makes sure we cannot run the kernel in SPMD mode.

Differential Revision: https://reviews.llvm.org/D106345
2021-07-26 21:26:07 -05:00
Joseph Huber e757a3b05f [OpenMP][NFC] Remove unncessary capture in RAII struct
Summary:
There was an unnecessary variable assigned to the information cache when we
only need it in the constructor to extract the function declaration.
2021-07-26 15:05:55 -04:00
Joseph Huber 58725c12bb [OpenMP] Introduce RAII to protect certain RTL calls from DCE
This patch introduces a new RAII struct that will temporarily make an OpenMP
RTL function have external linkage. This is done before the attributor is
invoked to prevent it from incorrectly removing some function definitions that
we will use later. For example, if we determine all calls to one function are
dead, because it has internal linkage it can safely be removed. Later when we
try to get an instance to that function to modify the source using
`getOrCreateRuntimeFunction` we will then get an empty declaration for that
function that won't be defined anywhere. This patch prevents this from
occurring.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106707
2021-07-25 14:15:47 -04:00
Shilei Tian ae69f46867 [AbstractAttributor] Refine logic to indicate pessimistic fixed point when folding `__kmpc_is_spmd_exec_mode`
Since we are using assumed information now, the logic should be refined to avoid
unncessary assertion.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106630
2021-07-23 13:36:47 -04:00
Giorgis Georgakoudis f97de4cb0b [OpenMPOpt] Move dedup runtime calls after init for target regions
Deduplication in OpenMPOpt finds redundant OpenMP runtime calls and replaces them with a single call placed in the earliest safe location in the IR. When deduplication happens in a target region this patch makes sure replacement calls are put after target_init.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106556
2021-07-23 05:54:01 -07:00
Giorgis Georgakoudis eaab880e45 [Attributor][Fix] Add overrides for AA2HS analysis 2021-07-22 18:20:14 -07:00
Giorgis Georgakoudis f8c40ed8f8 [OpenMP] Use AAHeapToStack/AAHeapToShared analysis in SPMDization
SPMDization D102307 detects incompatible OpenMP runtime calls to abort converting a target region to SPMD mode. Calls to memory allocation/de-allocation routines kmpc_alloc_shared, kmpc_free_shared are incompatible unless they are removed by AAHeapToStack/AAHeapToShared analysis. This patch extends SPMDization detection to include AAHeapToStack/AAHeapToShared analysis results for enlarging the scope of possible SPMDized regions detected.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105634
2021-07-22 18:08:37 -07:00
Shilei Tian 1a7f779022 [OpenMPOpt] Add support for BooleanStateWithSetVector
D101977 added `BooleanStateWithPtrSetVector` to store pointers to a set meanwhile
tracking boolean state. One of the limitation is that it can only store pointer.
We might want it to store other types of values, such as integer for parallel
level. This patch generalizes the idea and create `BooleanStateWithSetVector`.
`BooleanStateWithPtrSetVector` therefore becomes a type alias of `BooleanStateWithSetVector`.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106149
2021-07-22 13:12:29 -04:00
Johannes Doerfert c4b1fe05dd [OpenMP][FIX] Use name + type checks not only name checks for calls
A call that is analyzed in an optimization needs to be verified against
the name and type of the runtime function to avoid that we look at
arguments that do not exist (anymore). This can happen if the signature
was rewritten. Since we will not set RFI.Declaration if the type doesn't
match we can use it (if it's not null) to determine if the signature is
as expected.

Differential Revision: https://reviews.llvm.org/D106341
2021-07-21 22:51:05 -05:00
Joseph Huber 16206d17cd [OpenMP] Strip NoInline from known OpenMP runtime functions
This patch strips the NoInline attribute from known OpenMP runtime functions.
This is done so that we can denote certain runtime functions as NoInline to
ensure their call sites are intact so they can be checked by OpenMPOpt. We
don't wan't this noinline attribute to remain for any functions after OpenMPOpt
has been run however.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106482
2021-07-21 21:18:26 -04:00
Joseph Huber 196fe994b8 [OpenMP] Fold `__kmpc_is_generic_main_thread_id` if possible
This patch adds the ability to fold `__kmpc_is_generic_main_thread_id` if we
know for a fact that it is executed by the initial thread using
AAExecutionDomain. This combined with folding `__kmpc_is_spmd_exec_mode` will
allow us to fully fold `__kmpc_is_generic_main_thread`.

Depends on D106438 D106437

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106439
2021-07-21 21:18:22 -04:00
Joseph Huber 4a66860424 [OpenMP] Add an option to disable function internalization
Function internalization can sometimes occur in situations where we want to
keep the call sites intact. This patch adds an option to disable function
internalization and prevents the device runtime from being internalized while
creating the bitcode library.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106438
2021-07-21 21:18:18 -04:00
Joseph Huber 7d57639264 [OpenMP] Add new execution mode for SPMD execution with Generic semantics
Qualified kernels can be transformed from generic-mode to SPMD mode using an
optimization in OpenMPOpt. This patch introduces a new execution mode to
indicate kernels that have been transformed from generic-mode to SPMD-mode.
These kernels have SPMD-mode execution, but need generic-mode semantics for
scheduling the blocks and threads. Without this far too few blocks will be
scheduled for a generic region as SPMD mode expects the trip count to be
divided by the number of threads.

Reviewed By: ggeorgakoudis

Differential Revision: https://reviews.llvm.org/D106460
2021-07-21 20:57:28 -04:00
Giorgis Georgakoudis 3f71b425b2 [Attributor] Preserve BBs and instructions added in AA manifests
Manifesting AbstractAttributes may add new BBs in the IR. This patch provides an interface to register those BBs in the Attributor so that those BBs and containing instructions are not deleted as dead.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106383
2021-07-21 11:27:00 -07:00
Giorgis Georgakoudis e8439ec893 [OpenMP] Set RequiresFullRuntime false in SPMDization
SPMDization in D102307 does not change the RequiresFullRuntime argument of kmpc_target_init/deinit calls. However, the constraints of SPMDization detection for converting a target region to SPMD mode should guarantee that the region does not require full runtime support. Hence, this patch sets RequiresFullRuntime to false for improved execution performance.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105556
2021-07-20 09:54:51 -07:00
Johannes Doerfert 97387fdf6d [OpenMP] Fix carefully track SPMDCompatibilityTracker
We did not properly use SPMDCompatibilityTracker in various places.
This patch makes sure we look at the validity properly and also fix
the state if we can.

Differential Revision: https://reviews.llvm.org/D106085
2021-07-19 22:47:03 -05:00
Shilei Tian d3454ee8d2 [AbstractAttributor] Fix two issues in folding __kmpc_is_spmd_exec_mode
This patch fixed two issues found when folding `__kmpc_is_spmd_exec_mode`:
1. When the reaching kernels are empty, it should not fold to generic mode.
2. When creating AA for the caller when updating information, the dependency
   should be required.

Reviewed By: ye-luo

Differential Revision: https://reviews.llvm.org/D106209
2021-07-17 13:13:44 -04:00
Joseph Huber b910a109f8 [OpenMP][NFC] Update the comment header for optimizations. 2021-07-16 14:13:13 -04:00
Joseph Huber 2c31d5ebfb [OpenMP] Add IDs to OpenMP remarks
This patch adds unique idenfitiers to the existing OpenMP remarks. This makes
it easier to identify the corresponding documentation for each remark that will
be hosted in the OpenMP webpage.

Depends on D105898

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105939
2021-07-16 14:07:03 -04:00
Joseph Huber eef6601b0f [OpenMP] Rework OpenMP remarks
This patch rewrites and reworks a few of the existing remarks to make the mmore
concise and consistent prior to writing the documentation for them.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105898
2021-07-16 14:07:00 -04:00
Shilei Tian c23da666b5 [Attributor] Add support for compound assignment for ChangeStatus
A common use of `ChangeStatus` is as follows:
```
ChangeStatus Changed = ChangeStatus::UNCHANGED;
Changed |= foo();
```
where `foo` returns `ChangeStatus` as well. Currently `ChangeStatus` doesn't
support compound assignment, we have to write as
```
Changed = Changed | foo();
```
which is not that convenient.

This patch add the support for compound assignment for `ChangeStatus`. Compound
assignment is usually implemented as a member function, and binary arithmetic
operator is therefore implemented using compound assignment. However, unlike
regular C++ class, enum class doesn't support member functions. As a result, they
can only be implemented in the way shown in the patch.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106109
2021-07-15 23:51:46 -04:00
Shilei Tian ca662297d5 [AbstractAttributor] Fold function calls to `__kmpc_is_spmd_exec_mode` if possible
In the device runtime there are many function calls to `__kmpc_is_spmd_exec_mode`
to query the execution mode of current kernels. In many cases, user programs
only contain target region executing in one mode. As a consequence, those runtime
function calls will only return one value. If we can get rid of these function
calls during compliation, it can potentially improve performance.

In this patch, we use `AAKernelInfo` to analyze kernel execution. Basically, for
each kernel (device) function `F`, we collect all kernel entries `K` that can
reach `F`. A new AA, `AAFoldRuntimeCall`, is created for each call site. In each
iteration, it will check all reaching kernel entries, and update the folded value
accordingly.

In the future we will support more function.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105787
2021-07-15 18:23:23 -04:00
Shilei Tian a70ef3f568 Revert "[AbstractAttributor] Fold function calls to `__kmpc_is_spmd_exec_mode` if possible"
This reverts commit 1100e4aafe.
2021-07-15 11:19:28 -04:00
Shilei Tian 1100e4aafe [AbstractAttributor] Fold function calls to `__kmpc_is_spmd_exec_mode` if possible
In the device runtime there are many function calls to `__kmpc_is_spmd_exec_mode`
to query the execution mode of current kernels. In many cases, user programs
only contain target region executing in one mode. As a consequence, those runtime
function calls will only return one value. If we can get rid of these function
calls during compliation, it can potentially improve performance.

In this patch, we use `AAKernelInfo` to analyze kernel execution. Basically, for
each kernel (device) function `F`, we collect all kernel entries `K` that can
reach `F`. A new AA, `AAFoldRuntimeCall`, is created for each call site. In each
iteration, it will check all reaching kernel entries, and update the folded value
accordingly.

In the future we will support more function.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105787
2021-07-13 22:28:35 -04:00
Johannes Doerfert 792aac9897 [Attributor][NFCI] Add UsedAssumedInformation to more interfaces
As with other Attributor interfaces we often want to know if assumed
information was used to answer a query. This is important if only
known information is allowed or if known information can lead to an
early fixpoint. The users have been adjusted but none of them utilizes
the new information yet.
2021-07-11 19:18:03 -05:00
Johannes Doerfert 514c033db1 [OpenMP] Detect SPMD compatible kernels and execute them as such
In the spirit of TRegions [0], this patch analyzes a kernel and tracks
if it can be executed in SPMD-mode. If so, we flip the arguments of
the __kmpc_target_init and deinit call to enable the mode. We also
update the `<kernel>_exec_mode` flag to indicate to the runtime we
changed the mode to SPMD.

The code analysis is done interprocedurally by extending the
AAKernelInfo abstract attribute to track SPMD compatibility as well.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

Differential Revision: https://reviews.llvm.org/D102307
2021-07-10 18:44:25 -05:00
Johannes Doerfert 8cb7d71355 [OpenMP][FIX] Add missing `)` to remark 2021-07-10 18:40:32 -05:00
Johannes Doerfert d9659bf6a0 [OpenMP] Create custom state machines for generic target regions
In the spirit of TRegions [0], this patch creates a custom state
machine for a generic target region based on the potentially called
parallel regions.

The code analysis is done interprocedurally via an abstract attribute
(AAKernelInfo). All outermost parallel regions are collected and we
check if there might be unknown outermost parallel regions for which
we need an indirect call. Other AAKernelInfo extensions are expected.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

Differential Revision: https://reviews.llvm.org/D101977
2021-07-10 17:57:08 -05:00
Johannes Doerfert e2cfbfcc0c [OpenMP] Unified entry point for SPMD & generic kernels in the device RTL
In the spirit of TRegions [0], this patch provides a simpler and uniform
interface for a kernel to set up the device runtime. The OMPIRBuilder is
used for reuse in Flang. A custom state machine will be generated in the
follow up patch.

The "surplus" threads of the "master warp" will not exit early anymore
so we need to use non-aligned barriers. The new runtime will not have an
extra warp but also require these non-aligned barriers.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

This was in parts extracted from D59319.

Reviewed By: ABataev, JonChesterfield

Differential Revision: https://reviews.llvm.org/D101976
2021-07-10 17:53:56 -05:00
Johannes Doerfert c1c1fe9385 [Attributor] Reorganize AAHeapToStack
In order to simplify future extensions, e.g., the merge of
AAHeapToShared in to AAHeapToStack, we reorganize AAHeapToStack and the
state we keep for each malloc-like call. The result is also less
confusing as we only track malloc-like calls, not all calls. Further, we
only perform the updates necessary for a malloc-like to argue it can go
to the stack, e.g., we won't check all uses if we moved on to the
"must-be-freed" argument.

This patch also uses Attributor helps to simplify the allocated size,
alignment, and the potentially freed objects.

Overall, this is mostly a reorganization and only the use of the
optimistic helpers should change (=improve) the capabilities a bit.

Differential Revision: https://reviews.llvm.org/D104993
2021-07-10 16:32:24 -05:00
Nico Weber d3e7491333 Revert Attributor patch series
Broke check-clang, see https://reviews.llvm.org/D102307#2869065
Ran `git revert -n ebbe149a6f08535ede848a531a601ae6591cfbc5..269416d41908bb670f67af689155d5ab8eea689a`
2021-07-10 16:15:55 -04:00
Johannes Doerfert 269416d419 [Attributor][NFCI] Add UsedAssumedInformation to more interfaces
As with other Attributor interfaces we often want to know if assumed
information was used to answer a query. This is important if only
known information is allowed or if known information can lead to an
early fixpoint. The users have been adjusted but none of them utilizes
the new information yet.
2021-07-10 12:32:51 -05:00
Johannes Doerfert d39179d7fa [OpenMP] Detect SPMD compatible kernels and execute them as such
In the spirit of TRegions [0], this patch analyzes a kernel and tracks
if it can be executed in SPMD-mode. If so, we flip the arguments of
the __kmpc_target_init and deinit call to enable the mode. We also
update the `<kernel>_exec_mode` flag to indicate to the runtime we
changed the mode to SPMD.

The code analysis is done interprocedurally by extending the
AAKernelInfo abstract attribute to track SPMD compatibility as well.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

Differential Revision: https://reviews.llvm.org/D102307
2021-07-10 12:32:51 -05:00
Johannes Doerfert f0628c6ff7 [OpenMP] Create custom state machines for generic target regions
In the spirit of TRegions [0], this patch creates a custom state
machine for a generic target region based on the potentially called
parallel regions.

The code analysis is done interprocedurally via an abstract attribute
(AAKernelInfo). All outermost parallel regions are collected and we
check if there might be unknown outermost parallel regions for which
we need an indirect call. Other AAKernelInfo extensions are expected.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

Differential Revision: https://reviews.llvm.org/D101977
2021-07-10 12:32:50 -05:00
Johannes Doerfert 1d5711c3ee [OpenMP] Unified entry point for SPMD & generic kernels in the device RTL
In the spirit of TRegions [0], this patch provides a simpler and uniform
interface for a kernel to set up the device runtime. The OMPIRBuilder is
used for reuse in Flang. A custom state machine will be generated in the
follow up patch.

The "surplus" threads of the "master warp" will not exit early anymore
so we need to use non-aligned barriers. The new runtime will not have an
extra warp but also require these non-aligned barriers.

[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11

This was in parts extracted from D59319.

Reviewed By: ABataev, JonChesterfield

Differential Revision: https://reviews.llvm.org/D101976
2021-07-10 12:32:50 -05:00
Johannes Doerfert 1eb31d6de3 [Attributor] Reorganize AAHeapToStack
In order to simplify future extensions, e.g., the merge of
AAHeapToShared in to AAHeapToStack, we reorganize AAHeapToStack and the
state we keep for each malloc-like call. The result is also less
confusing as we only track malloc-like calls, not all calls. Further, we
only perform the updates necessary for a malloc-like to argue it can go
to the stack, e.g., we won't check all uses if we moved on to the
"must-be-freed" argument.

This patch also uses Attributor helps to simplify the allocated size,
alignment, and the potentially freed objects.

Overall, this is mostly a reorganization and only the use of the
optimistic helpers should change (=improve) the capabilities a bit.

Differential Revision: https://reviews.llvm.org/D104993
2021-07-10 12:32:50 -05:00
Joseph Huber ecabc6684f [OpenMP] Change analysis remarks to not emit on cold functions
The remarks will trigger on some functions that are marked cold, such as the
`__muldc3` intrinsic functions. Change the remarks to avoid these functions.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105196
2021-06-30 11:54:24 -04:00
Joseph Huber 0edb87773b [OpenMP] Add additional remarks for OpenMPOpt
This patch adds additional remarks, suggesting the use of `noescape` for failed
globalization and indicating when internalization failed.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105150
2021-06-30 09:49:25 -04:00
Joseph Huber 57ad2e1067 [OpenMP] Prevent OpenMPOpt from internalizing uncalled functions
Currently OpenMPOpt will only check if a function is a kernel before deciding not to internalize it. Any uncalled function that gets internalized will be trivially dead in the module so this is unnnecessary.

Depends on D102423

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D104890
2021-06-28 16:47:53 -04:00
Joseph Huber 13b2fba239 [OpenMP][NFC] Fix typo in OpenMPOpt 2021-06-28 09:49:14 -04:00
Joseph Huber 4024087731 [OpenMP][NFC] Fix missing argument 2021-06-28 09:15:01 -04:00
Joseph Huber 4a6bd8e3e7 [OpenMP] Increase attributor iterations on the GPU
Increase the number of attributor iterations on a GPU target. I forgot to
change this in D104416.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D104920
2021-06-28 08:50:49 -04:00
Joseph Huber 5ccb7424fa [OpenMP] Change OpenMPOpt to check openmp metadata
The metadata added in D102361 introduces a module flag that we can check
to determine if the module was compiled with `-fopenmp` enables. We can
now check for the precense of this instead of scanning the call graph
for OpenMP runtime functions.

Depends on D102361

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D102423
2021-06-25 16:34:22 -04:00
Joseph Huber 1cfdcae653 [Attributor] Fix AAExecutionDomain returning true on invalid states
This patch fixes a problem with the AAExecutionDomain attributor not
checking if it is in a valid state. This can cause it to incorrectly
return that a block is executed in a single threaded context after the
attributor failed for any reason.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D103186
2021-06-22 18:12:43 -04:00