The dead code elimination is a pass that looks very promising, but needs some
more compile-time tuning before enabling it by default seems sensible.
llvm-svn: 223965
This commit drops the Cloog support for Polly. The scripts and
documentation are changed to only use isl as prerequisity. In the code
all Cloog specific parts have been removed and all relevant tests have
been ported to the isl backend when it was created.
llvm-svn: 223141
Polly had a copy of this pass to create the canonical induction variables
necessary for the non-scev-based code generation. As we now always use SCEV
based code generation, canonical induction variables are not needed any more.
llvm-svn: 222979
SCEV based code generation has been the default for two weeks after having
been tested for a long time. We now drop the support the non-scev-based code
generation.
llvm-svn: 222978
The isl based backend has been tested since a long time and with the recently
commited OpenMP support the last missing piece of functionality was ported from
the CLooG backend.
The isl based backend gives us interesting new functionality:
- Run-time alias checks (enabled by default)
Optimize scops that contain possibly aliasing pointers. This feature has
largely increased the number of loop nests we consider for optimization.
Thanks Johannes!
- Delinearization (not yet enabled by default)
Model accesses to multi-dimensional arrays precisely. This will allow us to
understand kernels with multi-dimensional VLAs written in Julia, boost::ublas,
coremark or C99.
Thanks Sebastian!
- Generation of higher quality code
Sven and me spent a long time to optimize the quality of the generated code. A
major focus were expressions as they result from modulos/divisions or
piecewise affine expressions (a ? b : c).
- Full/Partial tile separation, polyhedral unrolling
The isl code generation provides functionality to generate specialized code
for core and cleanup loops and to specialize code using polyhedral context
information while unrolling statements.
(not yet exploited in Polly)
- Modifieable access functions
We can now use standard isl functionality to remap memory accesses to new
data locations. A standard use case is the use of shared memory, where
accesses to a larger region in global memory need to be mapped to a smaller
shared memory region using a modulo mapping.
(not yet exploited in Polly)
The cloog based code generation is still available for comparision, but is
scheduled for removal.
llvm-svn: 222101
This backend supports besides the classical code generation the upcoming SCEV
based code generation (which the existing CLooG backend does not support
robustly).
OpenMP code generation in the isl backend benefits from our run-time alias
checks such that the set of loops that can possibly be parallelized is a lot
larger.
The code was tested on LNT. We do not regress on builds without -polly-parallel.
When using -polly-parallel most tests work flawlessly, but a few issues still
remain and will be addressed in follow up commits.
SCEV/non-SCEV codegen:
- Compile time failure in ldecod and TimberWolfMC due a problem in our
run-time alias check generation triggered by pointers that escape through
the OpenMP subfunction (OpenMP specific).
- Several execution time failures. Due to the larger set of loops that we now
parallelize (compared to the classical code generation), we currently run
into some timeouts in tests with a lot loops that have a low trip count and
are slowed down by parallelizing them.
SCEV only:
- One existing failure in lencod due to llvm.org/PR21204 (not OpenMP specific)
OpenMP code generation is the last feature that was only available in the CLooG
backend. With the isl backend being the only one supporting features such as
run-time alias checks and delinearization, we will soon switch to use the isl
ast generator by the default and subsequently remove our dependency on CLooG.
http://reviews.llvm.org/D5517
llvm-svn: 222088
By adding braces into the DEBUG statement we can make clang-format format code
such as:
DEBUG(stmt1(); stmt2())
as multi-line code:
DEBUG({
stmt1();
stmt2();
});
This makes control-flow in debug statements easier to read.
llvm-svn: 220441
-Wcomment complained about a "multi-line comment" caused by the
ascii art used in ScopHelper to describe the CFG.
Differential Revision: http://reviews.llvm.org/D5618
llvm-svn: 219207
The command line flag -polly-annotate-alias-scopes controls whether or not
Polly annotates alias scopes in the new SCoP (default ON). This can improve
later optimizations as the new SCoP is basically an alias free environment for
them.
llvm-svn: 218877
This change will build all alias groups (minimal/maximal accesses
to possible aliasing base pointers) we have to check before
we can assume an alias free environment. It will also use these
to create Runtime Alias Checks (RTC) in the ISL code generation
backend, thus allow us to optimize SCoPs despite possibly aliasing
pointers when this backend is used.
This feature will be enabled for the isl code generator, e.g.,
--polly-code-generator=isl, but disabled for:
- The cloog code generator (still the default).
- The case delinearization is enabled.
- The case non-affine accesses are allowed.
llvm-svn: 218046
We use SplitEdge to split a conditional entry edge of the SCoP region.
However, SplitEdge can cause two different situations (depending on
whether or not the edge is critical). This patch tests
which one is present and deals with the former unhandled one.
It also refactors and unifies the case we have to change the basic
blocks of the SCoP to new ones (see replaceScopAndRegionEntry).
llvm-svn: 217802
Summary:
+ Refactor the runtime check (RTC) build function
+ Added helper function to create an PollyIRBuilder
+ Change the simplify region function to create not
only unique entry and exit edges but also enfore that
the entry edge is unconditional
+ Cleaned the IslCodeGeneration runOnScop function:
- less post-creation changes of the created IR
+ Adjusted and added test cases
Reviewers: grosser, sebpop, simbuerg, dpeixott
Subscribers: llvm-commits, #polly
Differential Revision: http://reviews.llvm.org/D5076
llvm-svn: 217508
This reverts commit 215684. The intention of the commit is great, but
unfortunately it seems to be the cause of 14 LNT test suite failures:
http://lab.llvm.org:8011/builders/perf-x86_64-penryn-O3-polly/builds/116
To make our buildbots and performance testers green until this issue is solved,
we temporarily revert this commit.
llvm-svn: 215816
The support is limited to signed modulo access and condition
expressions with a constant right hand side, e.g., A[i % 2] or
A[i % 9]. Test cases are modified according to this new feature and
new test cases are added.
Differential Revision: http://reviews.llvm.org/D4843
llvm-svn: 215684
Remove the PoCC and ScopLib support from Polly as we do not have a
user/maintainer for it.
Differential Revision: http://reviews.llvm.org/D4871
llvm-svn: 215563
In general this fixes ambiguity that can arise from using
a different namespace that declares the same symbols as
we do.
One example inside llvm would be:
createIndVarSimplifyPass(..);
Which can be found in:
llvm/Transforms/Scalar.h
and
polly/LinkAllPasses.h
llvm-svn: 210755
definition below all of the header #include lines, Polly edition.
If you want to know more details about this, you can see the recent
commits to Debug.h in LLVM. This is just the Polly segment of a cleanup
I'm doing globally for this macro.
llvm-svn: 206852
This ensures that the polly passes get properly registered both, when using
polly as a loadable module and when directly linking it into clang/opt/bugpoint.
llvm-svn: 204255
The module LLVMPolly.so links to that. There is really no reason to build a
large number of mini-libraries here, especially as we do have dependences
between the libraries that are not properly handled and that make linking fail
on darwin.
Submitted-by: David Fang <fang@csl.cornell.edu>
llvm-svn: 202743
SCoP invariant parameters with the different start value would deter parameter
sharing. For example, when compiling the following C code:
void foo(float *input) {
for (long j = 0; j < 8; j++) {
// SCoP begin
for (long i = 0; i < 8; i++) {
float x = input[j * 64 + i + 1];
input[j * 64 + i] = x * x;
}
}
}
Polly would creat two parameters for these memory accesses:
p_0: {0,+,256}
p_2: {4,+,256}
[j * 64 + i + 1] => MemRef_input[o0] : 4o0 = p_1 + 4i0
[j * 64 + i] => MemRef_input[o0] : 4o0 = p_0 + 4i0
These parameters only differ from start value. To enable parameter sharing,
we split the start value from SCEVAddRecExpr, so they would share a single
parameter that always has zero start value:
p0: {0,+,256}<%for.cond1.preheader>
[j * 64 + i + 1] => MemRef_input[o0] : 4o0 = 4 + p_1 + 4i0
[j * 64 + i] => MemRef_input[o0] : 4o0 = p_0 + 4i0
Such translation can make the polly-dependence much faster.
Contributed-by: Star Tan <tanmx_star@yeah.net>
llvm-svn: 187728
isl recently introduced isl_val as an abstract interface to represent arbitrary
precision numbers. This interface superseeds the old isl_int interface. In
contrast to the old interface which implemented arbitrary precision arithmetic
using macros that forward to the gmp library, the new library hides the math
library implementation in isl. This allows us to switch the math library used by
isl without affecting users such as Polly.
llvm-svn: 184529
Previously this happend to work for integers up to i64, but we got it wrong
for larger numbers. Fix this and add test cases to verify this keeps working.
Reported by: Sven Verdoolaege <skimo at kotnet dot org>
llvm-svn: 183986
Regions that have multiple entry edges are very common. A simple if condition
yields e.g. such a region:
if
/ \
then else
\ /
for_region
This for_region contains two entry edges 'then' -> 'for_region' and 'else' -> 'for_region'.
Previously we scheduled the RegionSimplify pass to translate such regions into
simple regions. With this patch, we now support them natively when the region is
in -loop-simplify form, which means the entry block should not be a loop header.
Contributed by: Star Tan <tanmx_star@yeah.net>
llvm-svn: 179586
We do not only need to understand that 'k * p' is a parameter expression, but
also need to store this expression in the set of parameters. Before this patch
we wrongly stored the two individual parameters %k and %p.
Reported by: Sebastian Pop <spop@codeaurora.org>
llvm-svn: 179485
After this commit, polly is clang-format clean. This can be tested with
'ninja polly-check-format'. Updates to clang-format may change this, but the
differences will hopefully be both small and general improvements to the
formatting.
We currently have some not very nice formatting for a couple of items, DEBUG()
stmts for example. I believe the benefit of being clang-format clean outweights
the not perfect layout of this code.
llvm-svn: 177796
Chandler Carruth