Commit Graph

293 Commits

Author SHA1 Message Date
Tobias Grosser 808cd69a92 Use schedule trees to represent execution order of statements
Instead of flat schedules, we now use so-called schedule trees to represent the
execution order of the statements in a SCoP. Schedule trees make it a lot easier
to analyze, understand and modify properties of a schedule, as specific nodes
in the tree can be choosen and possibly replaced.

This patch does not yet fully move our DependenceInfo pass to schedule trees,
as some additional performance analysis is needed here. (In general schedule
trees should be faster in compile-time, as the more structured representation
is generally easier to analyze and work with). We also can not yet perform the
reduction analysis on schedule trees.

For more information regarding schedule trees, please see Section 6 of
https://lirias.kuleuven.be/handle/123456789/497238

llvm-svn: 242130
2015-07-14 09:33:13 +00:00
Tobias Grosser ec46e5376d Print thread-identifiers in GPU debug output
This helps us to understand which thread prints which information.

llvm-svn: 241452
2015-07-06 15:36:16 +00:00
David Blaikie de867e1ee9 Fix the clang -Werror build (-Wbraced-scalar-init)
llvm-svn: 240172
2015-06-19 20:07:18 +00:00
Tobias Grosser e7e628cc07 Add NVIDIA vprintf printing to RuntimeDebugBuilder
2nd try, this time with the corresponding LLVM IRBuilder changes in place.

llvm-svn: 240119
2015-06-19 02:33:45 +00:00
Tobias Grosser 039955a44c Revert "Add NVIDIA vprintf printing to RuntimeDebugBuilder"
This reverts commit 239219 which requires some LLVM changes I forgot to commit.

Reported-by: Marshall Clow
llvm-svn: 239306
2015-06-08 16:24:49 +00:00
Tobias Grosser 6091417ebc Add NVIDIA vprintf printing to RuntimeDebugBuilder
llvm-svn: 239219
2015-06-06 08:43:22 +00:00
Tobias Grosser 785ee20cac Free two strings produced by isl
With this commit 'make check-polly' is now address sanitizer clean.

llvm-svn: 239131
2015-06-05 05:31:46 +00:00
Tobias Grosser 22adfb4373 Mark sdivs as 'exact' instead of lowering them ourselves
LLVM's instcombine already translates power-of-two sdivs that are known to be
exact to fast ashr instructions. Hence, there is no need to add this logic
ourselves.

Pointed-out-by: Johannes Doerfert
llvm-svn: 239025
2015-06-04 07:45:09 +00:00
Tobias Grosser 244c8297cf Lower signed-divisions without rounding to ashr instructions
llvm-svn: 238929
2015-06-03 15:14:58 +00:00
Tobias Grosser 224b162280 Only convert power-of-two floor-division with non-negative denominator
floord(a,b) === a ashr log_2 (b) holds for positive and negative a's, but
shifting only makes sense for positive values of b. The previous patch did
not consider this as isl currently always produces postive b's. To avoid future
surprises, we check that b is positive and only then apply the optimization.

We also now correctly check the return value of the dyn-cast.

No additional test case, as isl currently does not produce negative
denominators.

Reported-by: David Majnemer <david.majnemer@gmail.com>
llvm-svn: 238927
2015-06-03 14:43:01 +00:00
Tobias Grosser cb73f150d4 Translate power-of-two floor-division into ashr
Power-of-two floor divisions can be translated into an arithmetic shift
operation. This allows us to replace a complex lowering that requires division
operations:

  %pexp.fdiv_q.0 = sub i64 %21, 128
  %pexp.fdiv_q.1 = add i64 %pexp.fdiv_q.0, 1
  %pexp.fdiv_q.2 = icmp slt i64 %21, 0
  %pexp.fdiv_q.3 = select i1 %pexp.fdiv_q.2, i64 %pexp.fdiv_q.1, i64 %21
  %pexp.fdiv_q.4 = sdiv i64 %pexp.fdiv_q.3, 128

with a simple ashr:

  %polly.fdiv_q.shr = ashr i64 %21, 7

llvm-svn: 238905
2015-06-03 06:31:30 +00:00
Tobias Grosser cdb38e5625 Exploit non-negative numerators
isl marks known non-negative numerators in modulo (and soon also division)
operations. We now exploit this by generating unsigned operations. This is
beneficial as unsigned operations with power-of-two denominators will be
translated by isl to fast bitshift or bitwise and operations.

llvm-svn: 238577
2015-05-29 17:08:19 +00:00
Tobias Grosser b2f399264d Update isl to 93b8e43d
This update brings mostly interface cleanups, but also fixes two bugs in
imath (a memory leak, some undefined behavior).

llvm-svn: 238422
2015-05-28 13:32:11 +00:00
Tobias Grosser 7c3bad52dd Use value semantics for list of ScopStmt(s) instead of std::owningptr
David Blaike suggested this as an alternative to the use of owningptr(s) for our
memory management, as value semantics allow to avoid the additional interface
complexity caused by owningptr while still providing similar memory consistency
guarantees. We could also have used a std::vector, but the use of std::vector
would yield possibly changing pointers which currently causes problems as for
example the memory accesses carry pointers to their parent statements. Such
pointers should not change.

Reviewer: jblaikie, jdoerfert

Differential Revision: http://reviews.llvm.org/D10041

llvm-svn: 238290
2015-05-27 05:16:57 +00:00
Tobias Grosser eeb9f3ce15 Drop unnecessary 'this->' pointers
llvm-svn: 238257
2015-05-26 21:37:31 +00:00
Tobias Grosser 679dfafd33 Use unique_ptr to clarify ownership of ScopStmt
llvm-svn: 238090
2015-05-23 05:14:09 +00:00
Johannes Doerfert ecff11dcfb Add scalar and phi code generation
To reduce compile time and to allow more and better quality SCoPs in
  the long run we introduced scalar dependences and PHI-modeling. This
  patch will now allow us to generate code if one or both of those
  options are set. While the principle of demoting scalars as well as
  PHIs to memory in order to communicate their value stays the same,
  this allows to delay the demotion till the very end (the actual code
  generation). Consequently:
    - We __almost__ do not modify the code if we do not generate code
      for an optimized SCoP in the end. Thus, the early exit as well as
      the unprofitable option will now actually preven us from
      introducing regressions in case we will probably not get better
      code.
    - Polly can be used as a "pure" analyzer tool as long as the code
      generator is set to none.
    - The original SCoP is almost not touched when the optimized version
      is placed next to it. Runtime regressions if the runtime checks
      chooses the original are not to be expected and later
      optimizations do not need to revert the demotion for that part.
    - We will generate direct accesses to the demoted values, thus there
      are no "trivial GEPs" that select the first element of a scalar we
      demoted and treated as an array.

Differential Revision: http://reviews.llvm.org/D7513

llvm-svn: 238070
2015-05-22 23:43:58 +00:00
Tobias Grosser 5db5d2da13 Use base-pointer address space when creating new access functions
llvm-svn: 237785
2015-05-20 11:02:12 +00:00
Tobias Grosser 49ad36ca16 Add printing and testing to ScopArrayInfo
Being here, we extend the interface to return the element type and not a pointer
to the element type. We also provide a function to get the size (in bytes) of
the elements stored in this array.

We currently still store the element size as an innermost dimension in
ScopArrayInfo, which is somehow inconsistent and should be addressed in future
patches.

llvm-svn: 237779
2015-05-20 08:05:31 +00:00
Tobias Grosser 1128b36512 Adapt to IRBuilder::CreateCall interface change
The IRBuilder::CreateCall interface was changed in r237624 and now requires an
initializer list.

llvm-svn: 237666
2015-05-19 06:25:02 +00:00
Tobias Grosser b80def51e1 Drop unused PTX generator file
This code has been part of Polly's GPGPU backend, which has been remove together
with the code generation backend. Development now continues in an out-of-tree
branch.

llvm-svn: 237450
2015-05-15 15:41:14 +00:00
Tobias Grosser 09d3069740 Rename IslCodeGeneration to CodeGeneration
Besides class, function and file names, we also change the command line option
from -polly-codegen-isl to just -polly-codegen. The isl postfix is a leftover
from the times when we still had the CLooG based -polly-codegen. Today it is
just redundant and we drop it.

llvm-svn: 237099
2015-05-12 07:45:52 +00:00
Tobias Grosser d4ea2f48c4 Revert "Adjust formatting to latest clang-format change"
This reverts commit 236875. Daniel fixed the clang-format bug that introduced
the changed formatting.

llvm-svn: 236994
2015-05-11 13:43:04 +00:00
Tobias Grosser cd524dc51d Add explicit #includes for used isl features
llvm-svn: 236931
2015-05-09 09:36:38 +00:00
Tobias Grosser ba0d09227c Sort include directives
Upcoming revisions of isl require us to include header files explicitly, which
have previously been already transitively included. Before we add them, we sort
the existing includes.

Thanks to Chandler for sort_includes.py. A simple, but very convenient script.

llvm-svn: 236930
2015-05-09 09:13:42 +00:00
Tobias Grosser f7b5480474 Adjust formatting to latest clang-format change
llvm-svn: 236875
2015-05-08 16:10:53 +00:00
Tobias Grosser 0c55cb6071 Extract IslNodeBuilder into its own file
The IslNodeBuilder is a generic class that may be useful in other contexts
as well. Hence, we extract it into its own .h/.cpp file.

llvm-svn: 235873
2015-04-27 12:32:24 +00:00
Tobias Grosser f3ba5b5a40 Drop some unused headers
llvm-svn: 235871
2015-04-27 12:17:22 +00:00
Tobias Grosser 4245372bee Fix PTXGenerator after raw_pwrite_stream has been introduced
Without this patch Polly with GPGPU support enabled did not compile any more.

llvm-svn: 235868
2015-04-27 12:06:32 +00:00
Tobias Grosser 6325cd2fcd Remove flag '-polly-annotate-alias-scopes'
This option is enabled since a long time and there does not seem to be a
situation in which we would not want to print alias scopes. Remove this option
to reduce the set of command-line option combinations that may expose bugs.

llvm-svn: 235861
2015-04-27 10:43:10 +00:00
Tobias Grosser b68068bf62 Remove implementation of getNumberOfIterations from header [NFC]
We moved this implementation into the header file to share it between
the CLooG and isl code generator. As the CLooG code generator was dropped,
the implementation can be folded back into the .cpp file.

No functional change intended.

llvm-svn: 235860
2015-04-27 10:38:45 +00:00
Tobias Grosser 5483931117 Rename 'scattering' to 'schedule'
In Polly we used both the term 'scattering' and the term 'schedule' to describe
the execution order of a statement without actually distinguishing between them.
We now uniformly use the term 'schedule' for the execution order.  This
corresponds to the terminology of isl.

History: CLooG introduced the term scattering as the generated code can be used
as a sequential execution order (schedule) or as a parallel dimension
enumerating different threads of execution (placement). In Polly and/or isl the
term placement was never used, but we uniformly refer to an execution order as a
schedule and only later introduce parallelism. When doing so we do not talk
about about specific placement dimensions.

llvm-svn: 235380
2015-04-21 11:37:25 +00:00
David Blaikie f0e3d50d52 [opaque pointer type] More GEP API migrations
llvm-svn: 234131
2015-04-05 22:51:12 +00:00
Tobias Grosser eb18649ead Sign-extend in case of non-matching bitwidth
This change ensures that we sign-extend integer types in case non-matching
operands are encountered when generating a multi-dimensional access offset.

This fixes http://llvm.org/PR23124

Reported-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
llvm-svn: 234122
2015-04-05 17:36:42 +00:00
Tobias Grosser 7527e3f59c Do not use the POLLY vector code generator if only strip-mining is requested
This fixes http://llvm.org/PR23127

Reported-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
llvm-svn: 234113
2015-04-05 06:53:21 +00:00
Tobias Grosser 29e36dc0c6 Update isl to 285e92aea
This is mostly a set of schedule tree enhancements which are not yet directly
useful to Polly.

llvm-svn: 233567
2015-03-30 17:28:57 +00:00
Tobias Grosser 6794238c70 Code generate parameters and run-time checks after branching new code region
When creating parameters the SCEVexpander may introduce new induction variables,
that possibly create scalar dependences in the original scop, before we code
generate the scop. The resulting scalar dependences may then inhibit correct
code generation of the scop. To prevent this, we first version the code without
a run-time check and only then introduce new parameters and the run-time
condition. The if-condition that guards the original scop from being modified by
the SCEVexpander.

This change causes some test case changes as the run-time conditions are now
introduced in the split basic block rather than in the entry basic block.

This fixes http://llvm.org/PR22069

Test case reduced by: Karthik Senthil

llvm-svn: 233477
2015-03-28 09:34:40 +00:00
Tobias Grosser 2873645c51 Drop -polly-vectorizer-unroll-only option
This options was earlier used for experiments with the vectorizer, but to my
knowledge is not really used anymore. If anybody needs this, we can always
reintroduce this feature.

llvm-svn: 232934
2015-03-23 07:00:36 +00:00
Tobias Grosser bb4126470a Drop option to prepare code for the BB vectorizer
The BB vectorizer is deprecated and there is no point in generating code for it
any more. This option was introduced when there was not yet any loop vectorizer
in sight. Now being matured, Polly should target the loop vectorizer.

llvm-svn: 232099
2015-03-12 20:47:58 +00:00
Tobias Grosser 3284f1975c Assert in isl expression builder if id can not be found [NFC]
llvm-svn: 231865
2015-03-10 22:35:43 +00:00
Tobias Grosser c98950671d Fix compilation after DataLayout was added to ScevExpander
The corresponding LLVM commit is 231740.

llvm-svn: 231793
2015-03-10 15:24:33 +00:00
Tobias Grosser ed61e1fcd1 Update PTX generator to latest LLVM changes
llvm-svn: 231652
2015-03-09 13:35:19 +00:00
Johannes Doerfert f4af99bc6a [Formating] Fix formating
llvm-svn: 231612
2015-03-08 21:38:35 +00:00
Johannes Doerfert 7384399ddc [FIX] Add and force initialization for Pass * member
r231268 accidently dropped the initialization that is re-introduced
  here. The const will enforce initialization for the future.

llvm-svn: 231607
2015-03-08 20:14:34 +00:00
Tobias Grosser 90078c5580 Add sign-extension during codegen of index expressions
When code generating array index expressions the types of the different
components of the index expressions may not always match. We extend the type of
the index expression (if possible) and assert otherwise.

llvm-svn: 231592
2015-03-08 15:08:32 +00:00
Tobias Grosser 140b394e10 Fix compilation after 'Make DataLayout Non-Optional in the Module' commit
llvm-svn: 231362
2015-03-05 09:48:20 +00:00
Johannes Doerfert 7e6424ba5a Create a dependence struct to hold dependence information for a SCoP.
The new Dependences struct in the DependenceInfo holds all information
  that was formerly part of the DependenceInfo. It also provides the
  same interface for the user to access this information.

  This is another step to a more general ScopPass interface that does
  allow multiple SCoPs to be "in flight".

llvm-svn: 231327
2015-03-05 00:43:48 +00:00
Johannes Doerfert f6557f98a2 Rename the Dependences pass to DependenceInfo [NFC]
We rename the Dependences pass to DependenceInfo as a first step to a
  caching pass policy. The new DependenceInfo pass will later provide
  "Dependences" for a SCoP.

  To keep consistency the test folder is renamed too.

llvm-svn: 231308
2015-03-04 22:43:40 +00:00
Tobias Grosser bb8d1562ad Remove unnecessary dynamic memory management
llvm-svn: 231281
2015-03-04 19:33:31 +00:00
Tobias Grosser b021a4faad Add support for conditional 'and' and 'or' expressions
No test cases unfortunately as we do not yet generate isl_ast_op_and_then or
isl_ast_op_or_else. Those will be added in a later commit.

llvm-svn: 231268
2015-03-04 18:14:59 +00:00