Commit Graph

16 Commits

Author SHA1 Message Date
Tobias Grosser ecb94a0392 [GPGPU] Correctly initialize array order and fixed_element information
Summary:
This information is necessary for PPCG to perform correct life range reordering.
With these changes applied we can live-range reorder some of the important
kernels in COSMO.

We also update and rename one test case, which previously could not be optimized
and now is optimized thanks to live-range reordering. To preserve test coverage
we add a new test case scalar-writes-in-scop-requires-abort.ll, which exercises
our automatic abort in case of scalar writes in the kernel.

Reviewers: Meinersbur, bollu, singam-sanjay

Subscribers: nemanjai, pollydev, llvm-commits, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36929

llvm-svn: 311259
2017-08-19 20:21:22 +00:00
Tobias Grosser 861a387fac [GPGPU] Do not create copy statements when targetting managed memory
Summary:
They are not used and consequently do not even need to be computed. This reduces
the overall compile time for our kernel from 1m33s to 17s.

Reviewers: Meinersbur, bollu, singam-sanjay

Reviewed By: bollu

Subscribers: nemanjai, pollydev, llvm-commits, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36868

llvm-svn: 311157
2017-08-18 13:11:05 +00:00
Michael Kruse b936c4b332 [PPCG] Compile fix for MSVC.
Visual Studio, even the 2017 version, does not support C99 VLAs.

For VLA paramters, the length of the outermost dimension is not
required anyway, so remove it.

llvm-svn: 308643
2017-07-20 18:04:54 +00:00
Siddharth Bhat 3d4d752188 [PPCG] [2/3] Make polly specific PPCG Changes.
- This commit *WILL NOT COMPILE*. `PPCGCodeGeneration` requires changes
  since some of PPCG's internal data structures have been modified.

- Has polly-speific changes to PPCG. Polly exports certain functionality that
  is private to PPCG. It also creates stubs for large parts of the pet API as
  well as other functions in `ppcg/external.c` to keep the linker happy.

- This commit includes changes to CMakeLists.txt.

Differential Revision: https://reviews.llvm.org/D35676

llvm-svn: 308624
2017-07-20 15:48:22 +00:00
Siddharth Bhat 951515f236 [PPCG] [1/3] Bump up PPCG version to 0.07.
- This commit *WILL NOT COMPILE*, as it checks in vanilla PPCG 0.07
- We choose to introduce this commit into the history to cleanly display
  the Polly-specific changes made to PPCG.

Differential Revision: https://reviews.llvm.org/D35675

llvm-svn: 308623
2017-07-20 15:48:13 +00:00
Tobias Grosser 13c78e4d51 GPGPU: Emit data-transfer code
Also factor out getArraySize() to avoid code dupliciation and reorder some
function arguments to indicate the direction into which data is transferred.

llvm-svn: 276636
2016-07-25 12:47:39 +00:00
Tobias Grosser b9fc860a57 GPGPU: collect array references
Initialize the list of references to a GPU array to ensure that the arrays that
need to be passed to kernel calls are computed correctly.  Furthermore, the very
same information is also necessary to compute synchronization correctly. As the
functionality to compute these references is already available, what is left for
us to do is only to connect the necessary functionality to compute array
reference information.

llvm-svn: 275798
2016-07-18 15:44:32 +00:00
Tobias Grosser cda19c230c GPGPU: Abort if any dummy function is called
This ensures that accidental calls to these functions will break loadly instead
of corrupting the stack with invalid return values.

These functions have been introduced earlier as replacement of pet and parts of
ppcg which we will never use and consequently have not been imported or compiled
into Polly.

llvm-svn: 275680
2016-07-16 07:30:27 +00:00
Tobias Grosser cfa0361d35 GPGPU: Do not check for hidden declarations
We do not have them in Polly and the code to check for them is directly
referring to pet data structures which we do not have available.

This commit avoids undefined behavior. As such issues are difficult to
reproduce, this commit comes without a test case.

llvm-svn: 275553
2016-07-15 11:42:53 +00:00
Tobias Grosser 60f63b49f2 GPGPU: Model array access information
This allows us to derive host-device and device-host data-transfers.

llvm-svn: 275535
2016-07-15 07:05:54 +00:00
Tobias Grosser 69b4675180 GPGPU: Generate an AST for the GPU-mapped schedule
For this we need to provide an explicit list of statements as they occur in
the polly::Scop to ppcg.

We also setup basic AST printing facilities to facilitate debugging. To allow
code reuse some (minor) changes in ppcg are have been necessary.

llvm-svn: 275436
2016-07-14 15:51:37 +00:00
Tobias Grosser 60c6002570 GPGPU: Add dummy implementation for ast expression construction
Instead of calling to a pet function that does not return anything, we pass
our own dummy implementation to ppcg that always returns a nullptr. This
ensures that the list of ast expressions always contains a nullptr and we do
not accidentally free a random (uninitalized) pointer. This resolves the
last valgrind warning we see.

We provide an implementation for this function, when the generated AST
expressions can be used and consequently can be tested.

llvm-svn: 275435
2016-07-14 15:51:32 +00:00
Tobias Grosser aef5196f75 GPGPU: Map initial schedule to GPU schedule
This change now applies ppcg's GPU mapping on our initial schedule. For this
to work, we need to also initialize the set of all names (isl_ids) used in
the scop as well as the program context.

llvm-svn: 275396
2016-07-14 10:51:52 +00:00
Tobias Grosser f384594d5e GPGPU: compute new schedule from polly scop
To do so we copy the necessary information to compute an initial schedule from
polly::Scop to ppcg's scop. Most of the necessary information is directly
available and only needs to be passed on to ppcg, with the exception of 'tagged'
access relations, access relations that additionally carry information about
which memory access an access relation originates from.

We could possibly perform the construction of tagged accesses as part of
ScopInfo, but as this format is currently specific to ppcg we do not do this
yet, but keep this functionality local to our GPU code generation.

After the scop has been initialized, we compute data dependences and ask ppcg to
compute an initial schedule. Some of this functionality is already available in
polly::DependenceInfo and polly::ScheduleOptimizer, but to keep differences
to ppcg small we use ppcg's functionality here. We may later investiage if
a closer integration of these tools makes sense.

llvm-svn: 275390
2016-07-14 10:22:25 +00:00
Tobias Grosser e938517e37 GPGPU: create default initialized PPCG scop and gpu program
At this stage, we do not yet modify the IR but just generate a default
initialized ppcg_scop and gpu_prog and free both immediately. Both will later be
filled with data from the polly::Scop and are needed to use PPCG for GPU
schedule generation. This commit does not yet perform any GPU code generation,
but ensures that the basic infrastructure has been put in place.

We also add a simple test case to ensure the new code is run and use this
opportunity to verify that GPU_CODEGEN tests are only run if GPU code generation
has been enabled in cmake.

llvm-svn: 275389
2016-07-14 10:22:19 +00:00
Tobias Grosser a041239bb7 Add ppcg-0.04 to lib/External
ppcg will be used to provide mapping decisions for GPU code generation.

As we do not use C as input language, we do not include pet. However, we include
pet.h from pet 82cacb71 plus a set of dummy functions to ensure ppcg links
without problems.

The version of ppcg committed is unmodified ppcg-0.04 which has been well tested
in the context of LLVM. It does not provide an official library interface yet,
which means that in upcoming commits we will add minor modifications to make
necessary functionality accessible. We will aim to upstream these modifications
after we gained enough experience with GPU generation support in Polly to
propose a stable interface.

Reviewers: Meinersbur

Subscribers: pollydev, llvm-commits

Differential Revision: http://reviews.llvm.org/D22033

llvm-svn: 275274
2016-07-13 15:54:47 +00:00