Summary:
Since r306667, propagateInvalidStmtDomains gets a reference to an
InvalidDomainMap. As part of the branch leading to return false, the respective
domain is freed. It is, however, not removed from the InvalidDomainMap, leaking
a pointer to a freed object which results in a use-after-free. Fix this be
removing the domain from the map before returning.
We tried to derive a test case that reliably failes, but did not succeed in
producing one. Hence, for now the failures in our LNT bots must be sufficient
to keep this issue tested.
Reviewers: grosser, Meinersbur, bollu
Subscribers: bollu, nandini12396, pollydev, llvm-commits
Differential Revision: https://reviews.llvm.org/D34971
llvm-svn: 307499
- Check that we have invariant accesses.
- Use `-polly-use-llvm-names` for better names in the test.
- Rename test function to `f` for brevity.
llvm-svn: 307401
- This already works, but add this to ensure that there is no
regressions when I expand the invariant load hoisting ability of
`PPCGCodeGeneration`.
llvm-svn: 307398
- Instead of running with -O0, we enable the highest optimization level, but
then disable optimizations. This ensures that possibly important metadata
is still emitted.
- Update the code for attribute removal to work with latest LLVM
- Do not cut an arbitrary number of lines from the LL file. It is undocumented
why this was needed at the first place, and such a feature is likely to
break with trivial IR changes that may come in the future.
llvm-svn: 307355
- By definition, we can pass something as a `kill` to PPCG if we know
that no data can flow across a kill.
- This is useful for more complex examples where we have scalars that
are local to a scop.
- If the local is only used within a scop, we are free to kill it.
Differential Revision: https://reviews.llvm.org/D35045
llvm-svn: 307260
Summary:
Provide more context to the name of a GPU kernel by prefixing its name with the host function that calls it. E.g. The first kernel called by `gemm` would be `FUNC_gemm_KERNEL_0`.
Kernels currently follow the "kernel_#" (# = 0,1,2,3,...) nomenclature. This patch makes it easier to map host caller and device callee, especially when there are many kernels produced by Polly-ACC.
Reviewers: grosser, Meinersbur, bollu, philip.pfaffe, kbarton!
Reviewed By: grosser
Subscribers: nemanjai, pollydev
Tags: #polly
Differential Revision: https://reviews.llvm.org/D33985
llvm-svn: 307173
Polly did not use PPCG's live range reordering feature. Teach
PPCGCodeGeneration to use this.
Documentation on this is sparse, so much of the code is conservative.
We currently kill all phi nodes in a Scop by appending them to the
must_kill map we pass to PPCG. I do not have a proof of correctness,
but it seems to be intuitively correct.
We also do not handle `array_order`, which, quoting PPCG, is:
PPCG/gpu.h: "Order dependences on non-scalars."
It seems to consist of RAW dependences between arrays. We need to
pass this information for more complex privatization cases.
Differential Revision: https://reviews.llvm.org/D34941
llvm-svn: 307163
Summary: This is a general maintenance update
Reviewers: grosser
Subscribers: srhines, fedor.sergeev, pollydev, llvm-commits
Contributed-by: Maximilian Falkenstein <falkensm@student.ethz.ch>
Differential Revision: https://reviews.llvm.org/D34903
llvm-svn: 307090
Summary:
Introduce a "hybrid" `-polly-target` option to optimise code for either the GPU or CPU.
When this target is selected, PPCGCodeGeneration will attempt first to optimise a Scop. If the Scop isn't modified, it is then sent to the passes that form the CPU pipeline, i.e. IslScheduleOptimizerPass, IslAstInfoWrapperPass and CodeGeneration.
In case the Scop is modified, it is marked to be skipped by the subsequent CPU optimisation passes.
Reviewers: grosser, Meinersbur, bollu
Reviewed By: grosser
Subscribers: kbarton, nemanjai, pollydev
Tags: #polly
Differential Revision: https://reviews.llvm.org/D34054
llvm-svn: 306863
this is a great test file name based on this update, but I'll let Polly
folks sort out how they want this to work long-term, I just want tho
bots back.
llvm-svn: 306767
ScopStmts were being used in the computation of the Domain of the SCoPs
in ScopInfo. Once statements are split, there will not be a 1-to-1
correspondence between Stmts and Basic blocks. Thus this patch avoids
the use of getStmtFor() by creating a map of BB to InvalidDomain and
using it to compute the domain of the statements.
Contributed-by: Nanidini Singhal <cs15mtech01004@iith.ac.in>
Differential Revision: https://reviews.llvm.org/D33942
llvm-svn: 306667
Summary:
The NVPTX backend is now initialised within Polly. A language front-end need not be modified to initialise the backend, just for Polly.
Reviewers: Meinersbur, grosser
Reviewed By: Meinersbur
Subscribers: vchuravy, mgorny
Tags: #polly
Differential Revision: https://reviews.llvm.org/D31859
llvm-svn: 306649
This patch aims to implement the option of allocating new arrays created
by polly on heap instead of stack. To enable this option, a key named
'allocation' must be written in the imported json file with the value
'heap'.
We need such a feature because in a next iteration, we will implement a
mechanism of maximal static expansion which will need a way to allocate
arrays on heap. Indeed, the expansion is very costly in terms of memory
and doing the allocation on stack is not worth considering.
The malloc and the free are added respectively at polly.start and
polly.exiting such that there is no use-after-free (for instance in case
of Scop in a loop) and such that all memory cells allocated with a
malloc are free'd when we don't need them anymore.
We also add :
- In the class ScopArrayInfo, we add a boolean as member called IsOnHeap
which represents the fact that the array in allocated on heap or not.
- A new branch in the method allocateNewArrays in the ISLNodeBuilder for
the case of heap allocation. allocateNewArrays now takes a BBPair
containing polly.start and polly.exiting. allocateNewArrays takes this
two blocks and add the malloc and free calls respectively to
polly.start and polly.exiting.
- As IntPtrTy for the malloc call, we use the DataLayout one.
To do that, we have modified :
- createScopArrayInfo and getOrCreateScopArrayInfo such that it returns
a non-const SAI, in order to be able to call setIsOnHeap in the
JSONImporter.
- executeScopConditionnaly such that it return both start block and end
block of the scop, because we need this two blocs to be able to add
the malloc and the free calls at the right position.
Differential Revision: https://reviews.llvm.org/D33688
llvm-svn: 306540
Before we would 'guess' the correct location for the MergeBlock
that got introduced when executing a Scop conditionally. This
implicitly depends on the situation that at this point during
CodeGen there will be nothing between polly.start and polly.exiting.
With this commit we explicitly state that we want the block that
directly follows polly.exiting.
llvm-svn: 306398
This test fails, if polly is not linked into LLVM's tools. Our
lit site-config already deals with this by not adding the -load
option, if polly is linked into LLVM's tools.
llvm-svn: 306395
- In D33414, if any function call was found within a kernel, we would bail out.
- This is an over-approximation. This patch changes this by allowing the
`llvm.sqrt.*` family of intrinsics.
- This introduces an additional step when creating a separate llvm::Module
for a kernel (GPUModule). We now copy function declarations from the
original module to new module.
- We also populate IslNodeBuilder::ValueMap so it replaces the function
references to the old module to the ones in the new module
(GPUModule).
Differential Revision: https://reviews.llvm.org/D34145
llvm-svn: 306284
This commit returns both the start and the exit block that are created
by executeScopConditionally.
In a future commit we will make use of the exit block. Before we would
have to use the implicit property that there won't be any code generated
between polly.start and polly.exiting at the time of use to find the
correct block ('polly.exiting').
All usage location are semantically unchanged.
llvm-svn: 306283
The condition that disallowed code generation in PPCGCodeGeneration with
invariant loads is not required. I haven't been able to construct a
counterexample where this generates invalid code.
Differential Revision: https://reviews.llvm.org/D34604
llvm-svn: 306245
This reduces the compilation time of one reduced test case from Android from
16 seconds to 100 mseconds (we bail out), without negatively impacting any
other test case we currently have.
We still saw occasionally compilation timeouts on the AOSP buildbot. Hopefully,
those will go away with this change.
llvm-svn: 306235
During the construction of MemoryAccesses in ScopBuilder, BasicBlocks
were used in function parameters, assuming that the ScopStmt an be
directly derived from it. This won't be true anymore once we split
BasicBlocks into multiple ScopStmt. As a preparation for such a change
in the future, we instead pass the ScopStmt and avoid the use of
getStmtFor().
There are two occasions where a kind of mapping from BasicBlock to
ScopStmt is still required.
1. Get the statement representing the incoming block of a `PHINode`
using `getLastStmtOf`.
2. One statement is required to write a scalar to be readable by those
which need it. This is most often the statement which contains its
definition, which we get using `getStmtFor(Instruction*)`.
Differential Revision: https://reviews.llvm.org/D34369
llvm-svn: 306132
This allows us to bail out both in case the lexmin/max computation is too
expensive, but also in case the commulative cost across an alias group is
too expensive. This is an improvement of r303404, which did not seem to
be sufficient to keep the Android Buildbot quiet.
llvm-svn: 306087
r303971 added an assertion that SCEV addition involving an AddRec
and a SCEVUnknown must involve a dominance relation: either the
SCEVUnknown value dominates the AddRec's loop, or the AddRec's
loop header dominates the SCEVUnknown. This is generally fine
for most usage of SCEV because it isn't possible to write an
expression in IR which would violate it, but it's a bit inconvenient
here for polly.
To solve the issue, just avoid creating a SCEV expression which
triggers the asssertion.
I'm not really happy with this solution, but I don't have any better
ideas.
Fixes https://bugs.llvm.org/show_bug.cgi?id=33464.
Differential Revision: https://reviews.llvm.org/D34259
llvm-svn: 305864
Ensure that all array base pointers are assigned before generating
aliasing metadata by allocating new arrays beforehand.
Before this patch, getBasePtr() returned nullptr for new arrays because
the arrays were created at a later point. Nullptr did not match to any
array after the created array base pointers have been assigned and when
the loads/stores are generated.
llvm-svn: 305675
In r304074 we introduce a patch to accept results from side effect free
functions into SCEV modeling. This causes rejection of cases where the
call is happening outside the SCoP. This patch checks if the call is
outside the Region and treats the results as a parameter (SCEVType::PARAM)
to the SCoP instead of returning SCEVType::INVALID.
Patch by Sameer Abu Asal.
llvm-svn: 305423
Remove examples 'load_Polly_into_clang' and 'manual_matmul'. This information is
now available in our SPHINX docs (*).
(*) Thanks to Singapuram Sanjay Srivallabh <singapuram.sanjay@gmail.com> who
contributed the SPHINX docs update!
llvm-svn: 305186
In `PPCGCodeGeneration`, we try to take the references of every `Value`
that is used within a Scop to offload to the kernel. This occurs in
`GPUNodeBuilder::createLaunchParameters`.
This breaks if one of the values is a function pointer, since one of
these cases will trigger:
1. We try to to take the references of an intrinsic function, and this
breaks at `verifyModule`, since it is illegal to take the reference of
an intrinsic.
2. We manage to take the reference to a function, but this fails at
`verifyModule` since the function will not be present in the module that
is created in the kernel.
3. Even if `verifyModule` succeeds (which should not occur), we would
then try to call a *host function* from the *device*, which is
illegal runtime behaviour.
So, we disable this entire range of possibilities by simply not allowing
function references within a `Scop` which corresponds to a kernel.
However, note that this is too conservative. We *can* allow intrinsics
within kernels if the backend can lower the intrinsic correctly. For
example, an intrinsic like `llvm.powi.*` can actually be lowered by the `NVPTX`
backend.
We will now gradually whitelist intrinsics which are known to be safe.
Differential Revision: https://reviews.llvm.org/D33414
llvm-svn: 305185
Tobias Grosser