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
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
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
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
Previously, we would generate one performance counter for all scops.
Now, we generate both the old information, as well as a per-scop
performance counter to generate finer grained information.
This patch needed a way to generate a unique name for a `Scop`.
The start region, end region, and function name combined provides a
unique `Scop` name. So, `Scop` has a new public API to provide its start
and end region names.
Differential Revision: https://reviews.llvm.org/D33723
llvm-svn: 304528
Ignored intrinsics are ignored at code generation, therefore do not
need to be part of the instruction list.
Specifically, llvm.lifetime.* intrinisics are removed before code
generation, referencing them would cause a use-after-free error.
Contributed-by: Nandini Singhal <cs15mtech01004@iith.ac.in>
Differential Revision: https://reviews.llvm.org/D33768
llvm-svn: 304483
Such instructions are generates on-demand by the CodeGenerator and thus
do not need representation in a statement.
Differential Revision: https://reviews.llvm.org/D33642
llvm-svn: 304151
Should not have 'fixed' the formatting issue, I did not have the most
recent version of `clang-format`.
This reverts commit 761b1268359e14e59142f253d77864a29d55c56c.
llvm-svn: 304148
- Fix formatting in `RegisterPasses.cpp`.
- `assert` tried to compare `isl::boolean` against `long`. Explicitly
construct `bool` from `isl::boolean`. This allows the implicit cast of
`bool` to `long.
llvm-svn: 304146
Certain affine memory accesses which we model today might contain products of
parameters which we might combined into a new parameter to be able to create an
affine expression that represents these memory accesses. Especially in the
context of OpenCL, this approach looses information as memory accesses such as
A[get_global_id(0) * N + get_global_id(1)] are assumed to be linear. We
correctly recover their multi-dimensional structure by assuming that parameters
that are the result of a function call at IR level likely are not parameters,
but indeed induction variables. The resulting access is now
A[get_global_id(0)][get_global_id(1)] for an array A[][N].
llvm-svn: 304075
Side-effect free function calls with only constant parameters can be easily
re-generated and consequently do not prevent us from modeling a SCEV. This
change allows array subscripts to reference function calls such as
'get_global_id()' as used in OpenCL.
We use the function name plus the constant operands to name the parameter. This
is possible as the function name is required and is not dropped in release
builds the same way names of llvm::Values are dropped. We also provide more
readable names for common OpenCL functions, to make it easy to understand the
polyhedral model we generate.
llvm-svn: 304074
Summary: This patch outputs all the list of instructions in BlockStmts.
Reviewers: Meinersbur, grosser, bollu
Subscribers: bollu, llvm-commits, pollydev
Differential Revision: https://reviews.llvm.org/D33163
llvm-svn: 304062
It seems we are still spending too much time on rare inputs, which continue to
timeout the AOSP buildbot. Let's see if a further reduction is sufficient.
llvm-svn: 303807
Summary:
My goal is to make the newly added `AllowWholeFunctions` options more usable/powerful.
The changes to ScopBuilder.cpp are exclusively checks to prevent `Region.getExit()` from being dereferenced, since Top Level Regions (TLRs) don't have an exit block.
In ScopDetection's `isValidCFG`, I removed a check that disallowed ReturnInstructions to have return values. This might of course have been intentional, so I would welcome your feedback on this and maybe a small explanation why return values are forbidden. Maybe it can be done but needs more changes elsewhere?
The remaining changes in ScopDetection are simply to consider the AllowWholeFunctions option in more places, i.e. allow TLRs when it is set and once again avoid derefererncing `getExit()` if it doesn't exist.
Finally, in ScopHelper.cpp I extended `polly::isErrorBlock` to handle regions without exit blocks as well: The original check was if a given BasicBlock dominates all predecessors of the exit block. Therefore I do the same for TLRs by regarding all BasicBlocks terminating with a ReturnInst as predecessors of a "virtual" function exit block.
Patch by: Lukas Boehm
Reviewers: philip.pfaffe, grosser, Meinersbur
Reviewed By: grosser
Subscribers: pollydev, llvm-commits, bollu
Tags: #polly
Differential Revision: https://reviews.llvm.org/D33411
llvm-svn: 303790
Summary: This patch ports DependenceInfo to the new ScopPassManager. Printing is implemented as a seperate printer pass.
Reviewers: grosser, Meinersbur
Reviewed By: grosser
Subscribers: llvm-commits, pollydev
Tags: #polly
Differential Revision: https://reviews.llvm.org/D33421
llvm-svn: 303621
This speeds up scop modeling for scops with many redundent existentially
quantified constraints. For the attached test case, this change reduces
scop modeling time from minutes (hours?) to 0.15 seconds.
This change resolves a compilation timeout on the AOSP build.
Thanks Eli for reporting _and_ reducing the test case!
Reported-by: Eli Friedman <efriedma@codeaurora.org>
llvm-svn: 303600
Allow the BlockGenerator to generate memory writes that are not defined
over the complete statement domain, but only over a subset of it. It
generates a condition that evaluates to 1 if executing the subdomain,
and only then execute the access.
Only write accesses are supported. Read accesses would require a PHINode
which has a value if the access is not executed.
Partial write makes DeLICM able to apply mappings that are not defined
over the entire domain (for instance, a branch that leaves a loop with
a PHINode in its header; a MemoryKind::PHI write when leaving is never
read by its PHI read).
Differential Revision: https://reviews.llvm.org/D33255
llvm-svn: 303517
- We use the outermost dimension of arrays since we need this
information to generate GPU transfers.
- In general, if we do not know the outermost dimension of the array
(because the indexing expression is non-affine, for example) then we
simply cannot generate transfer code.
- However, for Fortran arrays, we can use the Fortran array
representation which stores the dimensions of all arrays.
- This patch uses the Fortran array representation to generate code that
computes the outermost dimension size.
Differential Revision: https://reviews.llvm.org/D32967
llvm-svn: 303429
In r302231 we mistakenly use bitwise or (|) instead of logical
or (||). This patch fixes that.
Contributed-by: Sameer AbuAsal <sabuasal@codeaurora.org>
Differential Revision: https://reviews.llvm.org/D33337
llvm-svn: 303386
Summary:
- Rename global / local naming convention that did not make much sense
to Visible / Invisible, where the visible refers to whether the ALLOCATE
call to the Fortran array is present in the current module or not.
- This match now works on both cross fortran module globals and on
parameters to functions since neither of them are necessarily allocated
at the point of their usage.
- Add testcase that matches against both a load and a store against
function parameters.
Differential Revision: https://reviews.llvm.org/D33190
llvm-svn: 303356
This patch adds both a ScopAnalysisManager and a ScopPassManager.
The ScopAnalysisManager is itself a Function-Analysis, and manages
analyses on Scops. The ScopPassManager takes care of building Scop pass
pipelines.
This patch is marked WIP because I've left two FIXMEs which I need to
think about some more. Both of these deal with invalidation:
Deferred invalidation is currently not implemented. Deferred
invalidation deals with analyses which cache references to other
analysis results. If these results are invalidated, invalidation needs
to be propagated into the caching analyses.
The ScopPassManager as implemented assumes that ScopPasses do not affect
other Scops in any way. There has been some discussion about this on
other patch threads, however it makes sense to reiterate this for this
specific patch.
I'm uploading this patch even though it's incomplete to encourage
discussion and give you an impression of how this is going to work.
Differential Revision: https://reviews.llvm.org/D33192
llvm-svn: 303062
- This breaks the previous assumption that Fortran Arrays are `GlobalValue`.
- The names of functions were getting unwieldy. So, I renamed the
Fortran related functions.
Differential Revision: https://reviews.llvm.org/D33075
llvm-svn: 303040
Summary: This is a proof of concept of how to port polly-passes to the new PassManager architecture. This approach works ootb for Function-Passes, but might not be directly applicable to Scop/Region-Passes. While we could just run the Analyses/Transforms over functions instead, we'd surrender the nice pipelining behaviour we have now.
Reviewers: Meinersbur, grosser
Reviewed By: grosser
Subscribers: pollydev, sanjoy, nemanjai, llvm-commits
Tags: #polly
Differential Revision: https://reviews.llvm.org/D31459
llvm-svn: 302902
Siddharth Bhat