Commit Graph

1922 Commits

Author SHA1 Message Date
Tobias Grosser e1a98343a1 GPGPU: Verify kernel IR before generating assembly
llvm-svn: 276550
2016-07-24 06:43:17 +00:00
Michael Kruse 977d38bd87 Remove unused parameters from simplifySCoP(). NFC.
llvm-svn: 276444
2016-07-22 17:31:17 +00:00
Tobias Grosser 74dc3cb431 GPGPU: Generate PTX assembly code for the kernel modules
Run the NVPTX backend over the GPUModule IR and write the resulting assembly
code in a string.

To work correctly, it is important to invalidate analysis results that still
reference the IR in the kernel module. Hence, this change clears all references
to dominators, loop info, and scalar evolution.

Finally, the NVPTX backend has troubles to generate code for various special
floating point types (not surprising), but also for uncommon integer types. This
commit does not resolve these issues, but pulls out problematic test cases into
separate files to XFAIL them individually and resolve them in future (not
immediate) changes one by one.

llvm-svn: 276396
2016-07-22 07:11:12 +00:00
Tobias Grosser edb885cb12 GPGPU: generate code for ScopStatements
This change introduces the actual compute code in the GPU kernels. To ensure
all values referenced from the statements in the GPU kernel are indeed available
we scan all ScopStmts in the GPU kernel for references to llvm::Values that
are not yet covered by already modeled outer loop iterators, parameters, or
array base pointers and also pass these additional llvm::Values to the
GPU kernel.

For arrays used in the GPU kernel we introduce a new ScopArrayInfo object, which
is referenced by the newly generated access functions within the GPU kernel and
which is used to help with code generation.

llvm-svn: 276270
2016-07-21 13:15:59 +00:00
Tobias Grosser 86083da0ec IslNodeBuilder: expose addReferencesFromStmt [NFC]
This will be used by Polly GPGPU to determine the values that need to be
passed to GPU kernels.

llvm-svn: 276269
2016-07-21 13:15:55 +00:00
Tobias Grosser 04b909fcca IslExprBuilder: allow to specify an external isl_id to ScopArrayInfo mapping
This is useful for external users using IslExprBuilder, in case they cannot
embed ScopArrayInfo data into their isl_ids, because the isl_ids either already
carry other information or the isl_ids have been created and their user pointers
cannot be updated any more.

llvm-svn: 276268
2016-07-21 13:15:51 +00:00
Tobias Grosser 9d12d8ade3 BlockGenerator: remove dead instructions in normal statements
This ensures that no trivially dead code is generated. This is not only cleaner,
but also avoids troubles in case code is generated in a separate function and
some of this dead code contains references to values that are not available.
This issue may happen, in case the memory access functions have been updated
and old getelementptr instructions remain in the code. With normal Polly,
a test case is difficult to draft, but the upcoming GPU code generation can
possibly trigger such problems. We will later extend this dead-code elimination
to region and vector statements.

llvm-svn: 276263
2016-07-21 11:48:36 +00:00
Tobias Grosser 9ea152714a JScop: Factor out importContext [NFC]
This makes the structure of the code clearer and reduces the size of runOnScop.

We also adjust the coding style to the latest LLVM style guide.

llvm-svn: 276246
2016-07-21 06:56:33 +00:00
Tobias Grosser dbe34f7c58 JScop: Factor out importContext [NFC]
This makes the structure of the code clearer and reduces the size of runOnScop.

We also adjust the coding style to the latest LLVM style guide.

llvm-svn: 276245
2016-07-21 06:56:31 +00:00
Tobias Grosser c602d3bc84 JScop: Factor out importSchedule [NFC]
This makes the structure of the code clearer and reduces the size of runOnScop.

We also adjust the coding style to the latest LLVM style guide.

llvm-svn: 276244
2016-07-21 06:56:28 +00:00
Tobias Grosser 9ec4f95234 Update isl to isl-0.17.1-191-g540b2fd
This update resolves a bug in computing lexicographic minima/maxima.

llvm-svn: 276138
2016-07-20 16:53:07 +00:00
Tobias Grosser f533571fd2 Update isl to isl-0.17.1-171-g233f589
This fixes an issue with equality detection that resulted in an assertion
being triggered during coalescing.

llvm-svn: 276094
2016-07-20 07:52:42 +00:00
Tobias Grosser 2d58a64e7f GPGPU: Bail out of scops with hoisted invariant loads
This is currently not supported and will only be added later. Also update the
test cases to ensure no invariant code hoisting is applied.

llvm-svn: 275987
2016-07-19 15:56:25 +00:00
Tobias Grosser 22117a8913 GPGPU: Disable invariant load hoisting for GPU code generation
This simplifies the upcoming patches to add code generation for ScopStmts. Load
hoisting support will later be added in a separate commit. This commit will
be implicitly tested by the subsequent GPGPU changes.

llvm-svn: 275969
2016-07-19 11:13:58 +00:00
Tobias Grosser 5260c041ea GPGPU: Emit in-kernel synchronization statements
We use this opportunity to further classify the different user statements that
can arise and add TODOs for the ones not yet implemented.

llvm-svn: 275957
2016-07-19 07:33:16 +00:00
Tobias Grosser 59ab070523 GPGPU: generate control flow within the kernel
llvm-svn: 275956
2016-07-19 07:33:11 +00:00
Tobias Grosser c84a1995fe GPGPU: add scop parameters to kernel arguments
llvm-svn: 275955
2016-07-19 07:33:06 +00:00
Tobias Grosser f6044bd0ef GPGPU: add host iterators to kernel arguments
llvm-svn: 275954
2016-07-19 07:32:55 +00:00
Tobias Grosser 472f9654c8 GPGPU: add intrinsic functions to obtain a kernels thread and block ids
llvm-svn: 275953
2016-07-19 07:32:44 +00:00
Tobias Grosser 32837fe313 GPGPU: create kernel function skeleton
Create for each kernel a separate LLVM-IR module containing a single function
marked as kernel function and taking one pointer for each array referenced
by this kernel. Add debugging output to verify the kernels are generated
correctly.

llvm-svn: 275952
2016-07-19 07:32:38 +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 1fb9b64dc0 GPGPU: Pull implementation out of class definition
This will allow us to see the full class definition even after we add
non-trivial implementations of the different member functions.

llvm-svn: 275797
2016-07-18 15:44:25 +00:00
Tobias Grosser 38fc0aed08 GPGPU: Create host control flow
Create LLVM-IR for all host-side control flow of a given GPU AST. We implement
this by introducing a new GPUNodeBuilder class derived from IslNodeBuilder.  The
IslNodeBuilder will take care of generating all general-purpose ast nodes, but
we provide our own createUser implementation to handle the different GPU
specific user statements. For now, we just skip any user statement and only
generate a host-code sceleton, but in subsequent commits we will add handling of
normal ScopStmt's performing computations, kernel calls, as well as host-device
data transfers. We will also introduce run-time check generation and LICM in
subsequent commits.

llvm-svn: 275783
2016-07-18 11:56:39 +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 2025173494 GPGPU: Format statements scheduled on the host ourselves
Otherwise ppcg would try to call into pet functionality that this not available,
which obviously will cause trouble. As we can easily print these statements
ourselves, we just do so.

llvm-svn: 275579
2016-07-15 17:12:41 +00:00
Tobias Grosser 2341fe9e76 GPGPU: Use schedule whole components for scheduler
This option increases the scalability of the scheduler and allows us to remove
the 'gisting' workaround we introduced in r275565 to handle a more complicated
test case. Another benefit of using this option is also that the generated
code looks a lot more streamlined.

Thanks to Sven Verdoolaege for reminding me of this option.

llvm-svn: 275573
2016-07-15 16:15:47 +00:00
Tobias Grosser e4725437e8 GPGPU: Drop domain constraints from flow dependences
This works around a shortcoming of the isl scheduler, which even for some
smaller test cases does not terminate in case domain constraints are part
of the flow dependences.

llvm-svn: 275565
2016-07-15 14:43:04 +00:00
Tobias Grosser 6293ba6973 GPGPU: Add memory reference tag ids to tagged accesses
It seems we forgot to actually add the memory access ids to the tagged accesses,
but instead just tagged the accesses with empty isl_ids. This issue was found
by inspection and without code generation it is difficult to test just by
itself. We fix it for now without test case and expect our code generation
tests to cover this later on.

llvm-svn: 275557
2016-07-15 12:44:27 +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 2d010daf85 GPGPU: Make sure scops with more than one array work
We use this opportunity to add a test case containing a scalar parameter.

llvm-svn: 275547
2016-07-15 10:51:14 +00:00
Tobias Grosser b307ed4d08 GPGPU: Free options to avoid memory leak
ppcg does not free the option structs for us. To avoid a memory leak we do this
ourselves.

llvm-svn: 275546
2016-07-15 10:32:22 +00:00
Tobias Grosser a56f8f8e58 GPGPU: Shorten ppcg include paths to avoid conflict with cuda.h
Instead of directly linking to ppcg's main source directory, we link to the
parent director. This allows us to access ppcg's include files with
'ppcg/cuda.h' and avoids a conflict with NVIDIA's cuda.h header.

Also drop an include directory that is currently not used.

llvm-svn: 275536
2016-07-15 07:50:36 +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 4eaedde530 GPGPU: Use a tile size of 32 by default
The tile size was previously uninitialized. As a result, it was often zero (aka.
no tiling), which is not what we want in general. More importantly, there was
the risk for arbitrary tile sizes to be choosen, which we did not observe, but
which still is highly problematic.

llvm-svn: 275418
2016-07-14 14:14:02 +00:00
Tobias Grosser bd81a7eebc Fix formatting
llvm-svn: 275397
2016-07-14 10:53:00 +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 681bd5688f GPGPU: Do not dump schedule by default
llvm-svn: 275395
2016-07-14 10:51:47 +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 562d3aa80a PPCGCodegen: Support compilation without GPU support
llvm-svn: 275310
2016-07-13 19:52:24 +00:00
Tobias Grosser 9dfe4e7c05 Add accelerator code generation pass skeleton
Add a new pass to serve as basis for automatic accelerator mapping in Polly.
The pass structure and the analyses preserved are copied from
CodeGeneration.cpp, as we will rely on IslNodeBuilder and IslExprBuilder for
LLVM-IR code generation.

Polly's accelerator code generation is enabled with -polly-target=gpu

I would like to use this commit as opportunity to thank Yabin Hu for his work in
the context of two Google summer of code projects during which he implemented
initial prototypes of the Polly accelerator code generation -- in parts this
code is already available in todays Polly (e.g., tools/GPURuntime). More will
come as part of the upcoming Polly ACC changes.

Reviewers: Meinersbur

Subscribers: pollydev, llvm-commits

Differential Revision: http://reviews.llvm.org/D22036

llvm-svn: 275275
2016-07-13 15:54:58 +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
Michael Kruse e448364320 [SCEVAffinator] Fix assertion checking for constant divisor.
An assertion in visitSDivInstruction() checked whether the divisor is constant
by checking whether the argument is a ConstantInt. However, SCEVValidator allows
the divisor to be simplified to a constant by ScalarEvolution.

We synchronize the implementation of SCEVValidator and SCEVAffinator to both
accept simplified SCEV expressions.

llvm-svn: 275174
2016-07-12 15:08:47 +00:00
Weiming Zhao 7614e178cb Fix a build warning of unhandled enum in switch
Summary: LLVM adds a new value FMRB_DoesNotReadMemory in the enumeration.

Reviewers: andrew.w.kaylor, chrisj, zinob, grosser, jdoerfert

Subscribers: Meinersbur, pollydev

Differential Revision: http://reviews.llvm.org/D22109

llvm-svn: 275085
2016-07-11 18:27:52 +00:00
Tobias Grosser faef9a7667 Fix gcc compile failure
Commit r275056 introduced a gcc compile failure due to us using two
types named 'Type', the first being the newly introduced member variable
'Type' the second being llvm::Type. We resolve this issue by renaming
the newly introduced member variable to AccessType.

llvm-svn: 275057
2016-07-11 12:27:04 +00:00
Tobias Grosser 4e2d9c45b9 InvariantEquivClassTy: Use struct instead of 4-tuple to increase readability
Summary:
With a struct we can use named accessors instead of generic std::get<3>()
calls. This increases readability of the source code.

Reviewers: jdoerfert

Subscribers: pollydev, llvm-commits

Differential Revision: http://reviews.llvm.org/D21955

llvm-svn: 275056
2016-07-11 12:15:10 +00:00
Tobias Grosser 5329277f81 load hoisting: compute memory access invalid context only for domain
We now compute the invalid context of memory accesses only for the domain under
which the memory access is executed. Without limiting ourselves to this
restricted domain, invalid accesses outside of the domain of actually executed
statement instances may result in the execution domain of the statement to
become empty despite the fact that the statement will actually be executed. As a
result, such scops would use unitialized values for their computations which
results in incorrect computations.

This fixes http://llvm.org/PR27944 and unbreaks the
-polly-position=before-vectorizer buildbots.

llvm-svn: 275053
2016-07-11 12:01:26 +00:00
Michael Kruse 586e579fe8 Fix assertion due to buildMemoryAccess.
For llvm the memory accesses from nonaffine loops should be visible,
however for polly those nonaffine loops should be invisible/boxed.

This fixes llvm.org/PR28245

Cointributed-by: Huihui Zhang <huihuiz@codeaurora.org>

Differential Revision: http://reviews.llvm.org/D21591

llvm-svn: 274842
2016-07-08 12:38:28 +00:00
Justin Bogner e2467baba8 Update for llvm r274769
llvm-svn: 274777
2016-07-07 18:03:30 +00:00
Tobias Grosser 932ec01328 isl: isl-0.17.1-164-gcbba1b6
This is a regular maintenance update to ensure the latest version of isl is
tested.

Interesting Changes:

  - AST nodes and expressions are now printed as YAML

llvm-svn: 274614
2016-07-06 09:11:00 +00:00
George Burgess IV 1a046de897 Try to fix polly buildbots.
Broken by r274589.

llvm-svn: 274595
2016-07-06 02:21:00 +00:00
Tobias Grosser 29a4dd92b7 CodegenCleanup: Drop CFLAA pass from codegen cleanup sequence
Since r274197 -polly-position=before-vectorizer caused various LNT failures
for example in SingleSource/Benchmarks/Linpack. These failures seem to only
occur when the CFLAA pass is scheduled in our codegen-cleanup passes, which
suggests that the way we call this AA pass is somehow problematic.  As this pass
is not of high importance, we drop the pass for now to prevent these failures
from happening. At a later point, we might investigate more in-depth why this
specific usage scenario caused correctness issues.

llvm-svn: 274427
2016-07-02 07:58:13 +00:00
Tobias Grosser 2ea7c6e8d1 Ensure parameter names are isl-compatible
Without this change it is not possible for isl to parse the resulting objects
from their string representation.

llvm-svn: 274350
2016-07-01 13:40:28 +00:00
Tobias Grosser 3898a0468c Propagate on-error status
This ensures that the error status set with -polly-on-isl-error-abort is
maintained even after running DependenceInfo and ScheduleOptimizer. Both
passes temporarily set the error status to CONTINUE as the dependence
analysis uses a compute-out and the scheduler may not be able to derive
a schedule. In both cases we want to not abort, but to handle the error
gracefully. Before this commit, we always set the error reporting to ABORT
after these passes. After this commit, we use the error reporting mode that was
active earlier.

This comes without a test case as this would require us to introduce (memory)
errors which would trigger the isl errors.

llvm-svn: 274272
2016-06-30 20:42:58 +00:00
Tobias Grosser af14993016 Simplify: get isl_ctx only once [NFC]
... instead of call S.getIslCtx() many times.

llvm-svn: 274271
2016-06-30 20:42:56 +00:00
Michael Kruse 73fa33b102 Create a dedicated header file for ScopBuilder. NFC.
It is only used internally by the ScopInfo pass. By moving it into its
own header file we avoid it being processed that use only ScopInfo.

llvm-svn: 273983
2016-06-28 01:37:28 +00:00
Michael Kruse 2133cb9a24 Move ScopBuilder into its own file. NFC.
The methods in ScopBuilder are used for the construction of a Scop,
while the remaining classes of ScopInfo are required by all passes that
use Polly's polyhedral analysis.

llvm-svn: 273982
2016-06-28 01:37:20 +00:00
Michael Kruse 6ff419c2ec Move getIndexExpressionsFromGEP() to ScopHelper. NFC.
This function is used by both ScopInfo and ScopBuilder. A common
location for this function is required when ScopInfo and ScopBuilder are
separated into separate files in the next commit.

llvm-svn: 273981
2016-06-28 01:37:13 +00:00
Michael Kruse a1a303f31e Add comment on why loops/regions can overlap. NFC.
The case is described in llvm.org/PR28071 which was fixed in the
previous commit.

llvm-svn: 273906
2016-06-27 19:00:55 +00:00
Michael Kruse 41f046a282 Fix assertion due to loop overlap with nonaffine region.
Reject and report regions that contains loops overlapping nonaffine region.
This situation typically happens in the presence of inifinite loops.

This addresses bug llvm.org/PR28071.

Differential Revision: http://reviews.llvm.org/D21312

Contributed-by: Huihui Zhang <huihuiz@codeaurora.org>
llvm-svn: 273905
2016-06-27 19:00:49 +00:00
Johannes Doerfert c5cfe75a6a [GSoC 2016] New function pass DependenceInfoWrapperPass
This patch addresses:
  - A new function pass to compute polyhedral dependences. This is
    required to avoid the region pass manager.
  - Stores a map of Scop to Dependence object for all the scops present
    in a function. By default, access wise dependences are stored.

Patch by Utpal Bora <cs14mtech11017@iith.ac.in>

Differential Revision: http://reviews.llvm.org/D21105

llvm-svn: 273881
2016-06-27 14:47:38 +00:00
Johannes Doerfert 4ba65a5622 [GSoC 2016]New function pass ScopInfoWrapperPass
This patch adds a new function pass ScopInfoWrapperPass so that the
polyhedral description of a region, the SCoP, can be constructed and
used in a function pass.

Patch by Utpal Bora <cs14mtech11017@iith.ac.in>

Differential Revision: http://reviews.llvm.org/D20962

llvm-svn: 273856
2016-06-27 09:32:30 +00:00
Johannes Doerfert b7e9713563 This patch updates memory management of ScopBuilder class.
1. SCoP object is not owned by ScopBuilder. It just creates a SCoP and
     hand over ownership through getScop() method.
  2. ScopInfoRegionPass owns the SCoP object for a given region.

Patch by Utpal Bora <cs14mtech11017@iith.ac.in>

Differential Revision: http://reviews.llvm.org/D20912

llvm-svn: 273855
2016-06-27 09:25:40 +00:00
Tobias Grosser 522478d2c0 clang-tidy: Add llvm namespace comments
llvm commonly adds a comment to the closing brace of a namespace to indicate
which namespace is closed. clang-tidy provides with llvm-namespace-comment
a handy tool to check for this habit. We use it to ensure we consitently use
namespace comments in Polly.

There are slightly different styles in how namespaces are closed in LLVM. As
there is no large difference between the different comment styles we go for the
style clang-tidy suggests by default.

To reproduce this fix run:

for i in `ls tools/polly/lib/*/*.cpp`; \
  clang-tidy -checks='-*,llvm-namespace-comment' -p build $i -fix \
  -header-filter=".*"; \
done

This cleanup was suggested by Eugene Zelenko <eugene.zelenko@gmail.com> in
http://reviews.llvm.org/D21488 and was split out to increase readability.

llvm-svn: 273621
2016-06-23 22:17:27 +00:00
Tobias Grosser 8a12bd9035 Update isl to isl-0.17.1-84-g72ffe88
This is a regular maintenance update to ensure we are testing with a recent
version of isl.

llvm-svn: 273597
2016-06-23 18:59:30 +00:00
Tobias Grosser 1a1056798b Fix separator in header comment
This cleanup was suggested by Eugene Zelenko <eugene.zelenko@gmail.com> in
http://reviews.llvm.org/D21488 and was split out to increase readability.

llvm-svn: 273437
2016-06-22 16:29:33 +00:00
Tobias Grosser 616449df6d Add missing copyright header
This cleanup was suggested by Eugene Zelenko <eugene.zelenko@gmail.com> in
http://reviews.llvm.org/D21488 and was split out to increase readability.

llvm-svn: 273436
2016-06-22 16:29:28 +00:00
Tobias Grosser 8dd653d983 clang-tidy: apply modern-use-nullptr fixes
Instead of using 0 or NULL use the C++11 nullptr symbol when referencing null
pointers.

This cleanup was suggested by Eugene Zelenko <eugene.zelenko@gmail.com> in
http://reviews.llvm.org/D21488 and was split out to increase readability.

llvm-svn: 273435
2016-06-22 16:22:00 +00:00
Roman Gareev 397a34a08d [NFC] Use isl_schedule_node_band_n_member to get the number of dimensions of a band node.
llvm-svn: 273400
2016-06-22 12:11:30 +00:00
Roman Gareev 42402c9e89 Apply all necessary tilings and unrollings to get a micro-kernel
This is the first patch to apply the BLIS matmul optimization pattern
on matmul kernels
(http://www.cs.utexas.edu/users/flame/pubs/TOMS-BLIS-Analytical.pdf).
BLIS implements gemm as three nested loops around a macro-kernel,
plus two packing routines. The macro-kernel is implemented in terms
of two additional loops around a micro-kernel. The micro-kernel
is a loop around a rank-1 (i.e., outer product) update.
In this change we create the BLIS micro-kernel by applying
a combination of tiling and unrolling. In subsequent changes
we will add the extraction of the BLIS macro-kernel
and implement the packing transformation.

Contributed-by: Roman Gareev <gareevroman@gmail.com>
Reviewed-by: Tobias Grosser <tobias@grosser.es>

Differential Revision: http://reviews.llvm.org/D21140

llvm-svn: 273397
2016-06-22 09:52:37 +00:00
Michael Kruse 6b4e928285 Replace ScalarReplAggregatesPass by SROAPass.
ScalarReplAggregatesPass was deprecated and replaced by SROAPass.
ScalarReplAggregatesPass got finally removed in LLVM commit r272737, hence this
patch is also a compile fix.

llvm-svn: 272783
2016-06-15 13:21:28 +00:00
Roman Gareev b17b9a8324 [NFC] Outline the application of register tiling.
llvm-svn: 272515
2016-06-12 17:20:05 +00:00
Tobias Grosser 43de17872a Recommit: "Simplify min/max expression generation"
As part of this simplification we pull complex logic out of the loop body and
skip the previously redundantly executed first loop iteration.

This is a partial recommit of r271514 and r271535 which where in conflict with
the revert in r272483 and consequently also had to be reverted temporarily.  The
original patch was contributed by Johannes Doerfert.

This patch is mostly a NFC, but dropping the first loop iteration can sometimes
result in slightly simpler code.

llvm-svn: 272502
2016-06-12 04:49:41 +00:00
Tobias Grosser 07b2095234 Update isl to isl-0.17.1-57-g1879898
With this update the isl AST generation extracts disjunctive constraints early
on. As a result, code that previously resulted in two branches with (close-to)
identical code within them:

  if (P <= -1) {
    for (int c0 = 0; c0 < N; c0 += 1)
      Stmt_store(c0);
  } else if (P >= 1)
    for (int c0 = 0; c0 < N; c0 += 1)
       Stmt_store(c0);

results now in only a single branch body:

  if (P <= -1 || P >= 1)
    for (int c0 = 0; c0 < N; c0 += 1)
       Stmt_store(c0);

This resolves http://llvm.org/PR27559

Besides the above change, this isl update brings better simplification of
sets/maps containing existentially quantified dimensions and fixes a bug in
isl's coalescing.

llvm-svn: 272500
2016-06-12 04:30:40 +00:00
Tobias Grosser 971336d330 Recommit: "[FIX] Determine insertion point during SCEV expansion"
This patch was originally contributed by Johannes Doerfert in r271892, but
was in conflict with the revert in r272483.

llvm-svn: 272486
2016-06-11 19:28:15 +00:00
Tobias Grosser 423642a597 Recommit: "Look through IntToPtr & PtrToInt instructions"
IntToPtr and PtrToInt instructions are basically no-ops that we can handle as
such. In order to generate them properly as parameters we had to improve the
ScopExpander, though the change is the first in the direction of a more
aggressive scalar synthetization.

This patch was originally contributed by Johannes Doerfert in r271888, but was
in conflict with the revert in r272483. This is a recommit with some minor
adjustment to the test cases to take care of differing instruction names.

llvm-svn: 272485
2016-06-11 19:26:08 +00:00
Tobias Grosser 3717aa5ddb This reverts recent expression type changes
The recent expression type changes still need more discussion, which will happen
on phabricator or on the mailing list. The precise list of commits reverted are:

- "Refactor division generation code"
- "[NFC] Generate runtime checks after the SCoP"
- "[FIX] Determine insertion point during SCEV expansion"
- "Look through IntToPtr & PtrToInt instructions"
- "Use minimal types for generated expressions"
- "Temporarily promote values to i64 again"
- "[NFC] Avoid unnecessary comparison for min/max expressions"
- "[Polly] Fix -Wunused-variable warnings (NFC)"
- "[NFC] Simplify min/max expression generation"
- "Simplify the type adjustment in the IslExprBuilder"

Some of them are just reverted as we would otherwise get conflicts. I will try
to re-commit them if possible.

llvm-svn: 272483
2016-06-11 19:17:15 +00:00
Tobias Grosser ef6ae7030d ScopDetection: Make enum function-local
The 'Color' enum is only used for irreducible control flow detection. Johannes
already moved this enum in r270054 from ScopDetection.h to ScopDetection.cpp to
limit its scope to a single cpp file. We now move it into the only function
where this enum is needed to make clear that it is only needed locally in this
single function.

Thanks to Johannes for pointing out this cleanup opportunity.

llvm-svn: 272462
2016-06-11 09:00:37 +00:00
Roman Gareev 827264de98 [NFC] "#include <ciso646>" is unnecessary, because "and", "or" were replaced
by "&&", "||".

llvm-svn: 272168
2016-06-08 16:44:11 +00:00
Johannes Doerfert 695c6b476a [FIX] Model the rounding behaviour of SRem correctly
llvm-svn: 272001
2016-06-07 12:00:37 +00:00
Johannes Doerfert 8448071d3e Refactor division generation code
This patch refactors the code generation for divisions. This allows to
  always generate a shift for a power-of-two division and to utilize
  information about constant divisors in order to truncate the result
  type.

llvm-svn: 271898
2016-06-06 14:56:17 +00:00
Johannes Doerfert c0ece9b67e [NFC] Generate runtime checks after the SCoP
We now generate runtime checks __after__ the SCoP code generation and
  not before, though they are still inserted at the same position int
  the code. This allows to modify the runtime check during SCoP code
  generation.

llvm-svn: 271894
2016-06-06 13:32:52 +00:00
Johannes Doerfert 4db8d80730 [FIX] Determine insertion point during SCEV expansion
llvm-svn: 271892
2016-06-06 13:05:21 +00:00
Johannes Doerfert 1a6b0f7f07 [NFC] Refactor assumption tracking interface
llvm-svn: 271890
2016-06-06 12:16:10 +00:00
Johannes Doerfert 6a6a671c72 [NFC] Simplify code
llvm-svn: 271889
2016-06-06 12:13:24 +00:00
Johannes Doerfert dedb7693ec Look through IntToPtr & PtrToInt instructions
IntToPtr and PtrToInt instructions are basically no-ops that we can handle as
  such. In order to generate them properly as parameters we had to improve the
  ScopExpander, though the change is the first in the direction of a more
  aggressive scalar synthetization.

llvm-svn: 271888
2016-06-06 12:12:27 +00:00
Johannes Doerfert b71900b89c [NFC] Simplify code
llvm-svn: 271886
2016-06-06 12:09:30 +00:00
Johannes Doerfert 4b2fd892ec [FIX] Do not recognize division by 0 as affine
llvm-svn: 271885
2016-06-06 12:08:34 +00:00
Johannes Doerfert f643785b14 Replace getSCEV with getSCEVAtScope
llvm-svn: 271881
2016-06-06 10:07:40 +00:00
Johannes Doerfert ba91a58e42 [NFC] Use the ScalarEvolution member of the SCEVAffinator
llvm-svn: 271880
2016-06-06 10:06:53 +00:00
Johannes Doerfert 48975276be [NFC] Coalesce invariant context sets early
llvm-svn: 271879
2016-06-06 10:06:07 +00:00
Johannes Doerfert 0767a511ba Use minimal types for generated expressions
We now use the minimal necessary bit width for the generated code. If
  operations might overflow (add/sub/mul) we will try to adjust the types in
  order to ensure a non-wrapping computation. If the type adjustment is not
  possible, thus the necessary type is bigger than the type value of
  --polly-max-expr-bit-width, we will use assumptions to verify the computation
  will not wrap. However, for run-time checks we cannot build assumptions but
  instead utilize overflow tracking intrinsics.

llvm-svn: 271878
2016-06-06 09:57:41 +00:00
Roman Gareev ba0fb97c0a [NFC] Check that a parameter of ScheduleTreeOptimizer::isMatrMultPattern contains a correct partial schedule
llvm-svn: 271780
2016-06-04 06:34:04 +00:00
Michael Kruse 5c527f9963 Fix modulo compared to zero.
In case of modulo compared to zero, we need to do signed modulo
operation as unsigned can give different results based on whether the
dividend is negative or not.

This addresses llvm.org/PR27707

Contributed-by: Chris Jenneisch <chrisj@codeaurora.org>

Reviewers: _jdoerfert, grosser, Meinersbur

Differential Revision: http://reviews.llvm.org/D20145

llvm-svn: 271707
2016-06-03 18:51:48 +00:00
Roman Gareev 4b8c7aeb62 [FIX] Fix potential issue related to subtraction from an unsigned 0 in circularShiftOutputDims
Reported-by: Mehdi Amini <mehdi.amini@apple.com>
Contributed-by: Michael Kruse <llvm@meinersbur.de>

Differential Revision: http://reviews.llvm.org/D20969

llvm-svn: 271705
2016-06-03 18:46:29 +00:00
Johannes Doerfert 6393ef135c Temporarily promote values to i64 again
Operands of binary operations that might overflow will be temporarily
  promoted to i64 again, though that is not a sound solution for the problem.

llvm-svn: 271538
2016-06-02 17:09:22 +00:00
Johannes Doerfert 4cf79d4ca4 [NFC] Avoid unnecessary comparison for min/max expressions
llvm-svn: 271535
2016-06-02 16:58:12 +00:00
Johannes Doerfert 6631bfdd1c [FIX] Correctly translate i1 expressions
llvm-svn: 271534
2016-06-02 16:57:12 +00:00
Johannes Doerfert 06445deda4 Simplify the schedule domain according to the context
llvm-svn: 271522
2016-06-02 15:07:41 +00:00
Johannes Doerfert e86a551618 [NFC] Rename ScopInfo to ScopBuilder
Contributed-by: Utpal Bora <cs14mtech11017@iith.ac.in>
  Reviewed-by: Michael Kruse <meinersbur@googlemail.com>
               Johannes Doerfert <doerfert@cs.uni-saarland.de>

  Differential Revision: http://reviews.llvm.org/D20831

llvm-svn: 271521
2016-06-02 14:36:34 +00:00
Matthew Simpson acae9e3b30 [Polly] Fix -Wunused-variable warnings (NFC)
llvm-svn: 271518
2016-06-02 14:26:38 +00:00
Johannes Doerfert 47f15f6d7e [NFC] Simplify min/max expression generation
llvm-svn: 271514
2016-06-02 11:20:52 +00:00
Johannes Doerfert d36553753e Simplify the type adjustment in the IslExprBuilder
We now have a simple function to adjust/unify the types of two (or three)
  operands before an operation that requieres the same type for all operands.
  Due to this change we will not promote parameters that are added to i64
  anymore if that is not needed.

llvm-svn: 271513
2016-06-02 11:15:57 +00:00
Johannes Doerfert a91c85a5b9 [FIX] Ensure wrapping checks for unary expressions
llvm-svn: 271512
2016-06-02 11:08:43 +00:00
Johannes Doerfert 5210da5897 Bail early for complex alias checks
llvm-svn: 271511
2016-06-02 11:06:54 +00:00
Roman Gareev 76614d3ed9 [GSoC 2016] [Polly] [FIX] Determination of statements that contain matrix
multiplication

Fix small issues related to characters, operators  and descriptions of tests.

Differential Revision: http://reviews.llvm.org/D20806

llvm-svn: 271264
2016-05-31 11:22:21 +00:00
Johannes Doerfert 99191c78c2 Decouple SCoP building logic from pass
Created a new pass ScopInfoRegionPass. As name suggests, it is a
  region pass and it is there to preserve compatibility with our
  existing Polly passes.  ScopInfoRegionPass will return a SCoP object
  for a valid region while the creation of the SCoP stays in the
  ScopInfo class.

  Contributed-by: Utpal Bora <cs14mtech11017@iith.ac.in>
  Reviewed-by: Tobias Grosser <tobias@grosser.es>,
               Johannes Doerfert <doerfert@cs.uni-saarland.de>

Differential Revision: http://reviews.llvm.org/D20770

llvm-svn: 271259
2016-05-31 09:41:04 +00:00
Michael Kruse 7410a27820 MSVC compile fix: #include <ciso646>. NFC.
This header is required to make the ISO 646 alternative operator
spellings ("and", "or" instead of "&&", "||") work. Should these
operators be replaced by the standard ones as already suggested by
Johannes, also remove this #include again.

llvm-svn: 271206
2016-05-30 14:27:14 +00:00
Sanjoy Das 03bcb910de [Polly] Remove usage of the `apply` function
Summary:
API-wise `apply` is a somewhat unidiomatic one-off function, and
removing the only(?) use in polly will let me remove it from SCEV's
exposed interface.

Reviewers: jdoerfert, Meinersbur, grosser

Subscribers: grosser, mcrosier, pollydev

Differential Revision: http://reviews.llvm.org/D20779

llvm-svn: 271177
2016-05-29 07:33:16 +00:00
Roman Gareev 9c3eb5960a Determination of statements that contain matrix multiplication
Add determination of statements that contain, in particular,
matrix multiplications and can be optimized with [1] to try to
get close-to-peak performance. It can be enabled
via polly-pm-based-opts, which is false by default.

Refs:
[1] - http://www.cs.utexas.edu/users/flame/pubs/TOMS-BLIS-Analytical.pdf

Contributed-by: Roman Gareev <gareevroman@gmail.com>
Reviewed-by: Tobias Grosser <tobias@grosser.es>

Differential Revision: http://reviews.llvm.org/D20575

llvm-svn: 271128
2016-05-28 16:17:58 +00:00
Michael Kruse 1007182cf7 [ScopInfo] Change removeMemoryAccesses to remove only one access. NFC.
This exposes the more basic operation for use by code not related to
invariant code hoisting.

llvm-svn: 270438
2016-05-23 14:45:58 +00:00
Michael Kruse 996fb611b3 Remove some unused local variables. NFC.
Found by clang static analyzer (http://llvm.org/reports/scan-build/)
and Visual Studio.

llvm-svn: 270432
2016-05-23 13:00:41 +00:00
Johannes Doerfert 0f0d209bec Use the SCoP directly for canSynthesize [NFC]
llvm-svn: 270429
2016-05-23 12:47:09 +00:00
Johannes Doerfert 57a7317fb8 Simplify ScopInfo function interfaces [NFC]
llvm-svn: 270428
2016-05-23 12:45:17 +00:00
Johannes Doerfert e0b08077bf Allow to check for dominance wrt. a SCoP [NFC]
llvm-svn: 270427
2016-05-23 12:43:44 +00:00
Johannes Doerfert ef74443c97 Duplicate part of the Region interface in the Scop class [NFC]
This allows to use the SCoP directly for various queries,
  thus to hide the underlying region more often.

llvm-svn: 270426
2016-05-23 12:42:38 +00:00
Johannes Doerfert 952b5304bc Add and use Scop::contains(Loop/BasicBlock/Instruction) [NFC]
llvm-svn: 270424
2016-05-23 12:40:48 +00:00
Johannes Doerfert 3f52e35471 Directly access information through the Scop class [NFC]
llvm-svn: 270421
2016-05-23 12:38:05 +00:00
Johannes Doerfert 25227fe7b0 Optimistic assume required invariant loads to be invariant
Before this patch we bailed if a required invariant load was potentially
  overwritten. However, now we will optimistically assume it is actually
  invariant and, to this end, restrict the valid parameter space as well as the
  execution context with regards to potential overwrites of the location.

llvm-svn: 270416
2016-05-23 10:40:54 +00:00
Johannes Doerfert 764b7e66f0 [FIX] Require base pointers of loads that might alias to be hoisted
Since the base pointer of a possibly aliasing pointer might not alias
  with any other pointer it (the base pointer) might not be tagged as
  "required invariant". However, we need it do be in order to compare
  the accessed addresses of the derived (possibly aliasing) pointer.

  This patch also tries to clean up the load hoisting a little bit.

llvm-svn: 270412
2016-05-23 09:26:46 +00:00
Johannes Doerfert 38a012c46b Simplify BlockGenerator::handleOutsideUsers interface [NFC]
llvm-svn: 270411
2016-05-23 09:14:07 +00:00
Johannes Doerfert 1dafea4114 Make the detection context non-constant [NFC]
llvm-svn: 270410
2016-05-23 09:07:08 +00:00
Johannes Doerfert a61eda7698 [FIX] Let ScalarEvolution forget hoisted values
We have to rethink the handling of escaping values in order to make
  this kind of "fixes" go away.

llvm-svn: 270409
2016-05-23 09:02:54 +00:00
Johannes Doerfert 1a4ad8f771 [FIX] Synthezise Sdiv/Srem/Udiv instructions correctly.
This patch simplifies the Sdiv/Srem/Udiv expansion and thereby
  prevents errors, e.g., regarding the insertion point.

llvm-svn: 270408
2016-05-23 08:55:43 +00:00
Johannes Doerfert cda1bd5048 Revert "Optimistic assume required invariant loads to be invariant"
This reverts commit 787e642207ca978f2e800140529fc7049ea1f3de until the
lnt failures are fixed.

llvm-svn: 270061
2016-05-19 13:47:34 +00:00
Johannes Doerfert cb77542d1c Optimistic assume required invariant loads to be invariant
So far we bailed if a required invariant load was potentially overwritten in
  the SCoP. From now on we will optimistically assume it is actually invariant
  and, to this end, restrict the valid parameter space.

llvm-svn: 270060
2016-05-19 13:24:10 +00:00
Johannes Doerfert 469db6a247 Move internal enum out of class declaration [NFC]
llvm-svn: 270054
2016-05-19 12:36:43 +00:00
Johannes Doerfert ffd222f2d6 Propagate the DetectionContext to the SCoP [NFC]
The SCoP now holds a reference to the ScopDetection::DetectionContext
  which allows to simplify the type of various methods and remove code.

llvm-svn: 270053
2016-05-19 12:34:57 +00:00
Johannes Doerfert 60dd9e1346 Compute the MaxLoopDepth during domain construction [NFC]
llvm-svn: 270052
2016-05-19 12:33:14 +00:00
Johannes Doerfert f5841a66af Remove leftover debug output [NFC]
llvm-svn: 270051
2016-05-19 12:32:54 +00:00
Johannes Doerfert 6dc3616195 Remove unsused methodes [NFC]
llvm-svn: 270050
2016-05-19 12:31:16 +00:00
Johannes Doerfert e6e3c9246a Check late for profitability
Before this patch we only expanded valid __and__ profitable region. Therefor
  we did not allow the expansion to create a profitable region from a
  non-profitable one.  With this patch we will remember and expand all valid
  regions and check for profitability only at the end.

  This patch increases the number of valid SCoPs in the LLVM-TS and SPEC
  2000/2006 by 28% (from 303 to 390), including the hot loop in hmmer.

llvm-svn: 269343
2016-05-12 20:21:50 +00:00
Johannes Doerfert 6c7639b380 Cleanup rejection log handling [NFC]
This patch cleans up the rejection log handling during the
  ScopDetection. It consists of two interconnected parts:
    - We keep all detection contexts for a function in order to provide
      more information to the user, e.g., about the rejection of
      extended/intermediate regions.
    - We remove the mutable "RejectLogs" member as the information is
      available through the detection contexts.

llvm-svn: 269323
2016-05-12 18:50:01 +00:00
Johannes Doerfert 5c2b556b13 Bring some comments up to date [NFC]
llvm-svn: 269301
2016-05-12 15:15:50 +00:00
Johannes Doerfert 6f1bb7a9d9 Support truncate operations
Truncate operations are basically modulo operations, thus we can model
  them that way. However, for large types we assume the operand to fit
  in the new type size instead of introducing a modulo with a very large
  constant.

llvm-svn: 269300
2016-05-12 15:13:49 +00:00
Johannes Doerfert 404a0f81ea Check overflows in RTCs and bail accordingly
We utilize assumptions on the input to model IR in polyhedral world.
  To verify these assumptions we version the code and guard it with a
  runtime-check (RTC). However, since the RTCs are themselves generated
  from the polyhedral representation we generate them under the same
  assumptions that they should verify. In other words, the guarantees
  that we try to provide with the RTCs do not hold for the RTCs
  themselves. To this end it is necessary to employ a different check
  for the RTCs that will verify the assumptions did hold for them too.

Differential Revision: http://reviews.llvm.org/D20165

llvm-svn: 269299
2016-05-12 15:12:43 +00:00
Johannes Doerfert 27d12d3d1f Invalidate unprofitable SCoPs after creation
If a profitable run is performed we will check if the SCoP seems to be
  profitable after creation but before e.g., dependence are computed. This is
  needed as SCoP detection only approximates the actual SCoP representation.
  In the end this should allow us to be less conservative during the SCoP
  detection while keeping the compile time in check.

llvm-svn: 269074
2016-05-10 16:38:09 +00:00
Johannes Doerfert bf9473b2d8 Weaken profitability constraints during ScopDetection
Regions with one affine loop can be profitable if the loop is
  distributable. To this end we will allow them to be treated as
  profitable if they contain at least two non-trivial basic blocks.

llvm-svn: 269064
2016-05-10 14:42:30 +00:00
Johannes Doerfert ede4ecaefb [FIX] Cleanup isl objects prior to early exit
llvm-svn: 269061
2016-05-10 14:01:21 +00:00
Johannes Doerfert 2b92a0e4ee Handle llvm.assume inside the SCoP
The assumption attached to an llvm.assume in the SCoP needs to be
  combined with the domain of the surrounding statement but can
  nevertheless be used to refine the context.

  This fixes the problems mentioned in PR27067.

llvm-svn: 269060
2016-05-10 14:00:57 +00:00
Johannes Doerfert 297c720d15 Propagate complexity problems during domain generation [NFC]
This patches makes the propagation of complexity problems during
  domain generation consistent. Additionally, it makes it less likely to
  encounter ill-formed domains later, e.g., during schedule generation.

llvm-svn: 269055
2016-05-10 13:06:42 +00:00
Johannes Doerfert 14b1cf35b5 [FIX] Create error-restrictions late
Before this patch we generated error-restrictions only for
  error-blocks, thus blocks (or regions) containing a not represented
  function call. However, the same reasoning is needed if the invalid
  domain of a statement subsumes its actual domain. To this end we move
  the generation of error-restrictions after the propagation of the
  invalid domains. Consequently, error-statements are now defined more
  general as statements that are assumed to be not executed.
  Additionally, we do not record an empty domain for such statements but
  a nullptr instead. This allows to distinguish between error-statements
  and dead-statements.

llvm-svn: 269053
2016-05-10 12:42:26 +00:00
Johannes Doerfert 2640454d1c Refactor simplifySCoP [NFC]
Remove obsolete code and decrease the indention in the
  Scop::simplifySCoP() function.

llvm-svn: 269049
2016-05-10 12:19:47 +00:00
Johannes Doerfert a60ad845c0 Simplify the internal representation according to the context [NFC]
We now use context information to simplify the domains and access
  functions of the SCoP instead of just aligning them with the parameter
  space.

llvm-svn: 269048
2016-05-10 12:18:22 +00:00
Johannes Doerfert e243753a4d Simplify access relation for invariant loads early [NFC]
llvm-svn: 269046
2016-05-10 11:59:59 +00:00
Johannes Doerfert 5f173d414e Prevent complex access ranges with low number of pieces.
Previously we checked the number of pieces to decide whether or not a
  invariant load was to complex to be generated. However, there are
  cases when e.g., divisions cause the complexity to spike regardless of
  the number of pieces. To this end we now check the number of totally
  involved dimensions which will increase with the number of pieces but
  also the number of divisions.

llvm-svn: 269045
2016-05-10 11:46:57 +00:00
Johannes Doerfert 56b377644a Expose interpretAsUnsigned in the SCEVAffinator [NFC]
This exposes the functionality to interpret a SCEV, or better the
  piece-wise function created from the SCEV, as an unsigned value
  instead of a signed one.

llvm-svn: 269044
2016-05-10 11:45:46 +00:00
Tobias Grosser 1022ca5646 Codegen: Enable the detection of min/max expressions
Min/max expressions are easier to read and can in some cases also result in
more concise IR that is generated as the min/max --- when lowered to a
cmp+select pattern -- commonly has a simpler condition then the ternary
condition isl would normally generate.

llvm-svn: 268855
2016-05-07 08:03:44 +00:00