Scops that only read seem generally uninteresting and scops that only write are
most likely initializations where there is also little to optimize. To not
waste compile time we bail early.
Differential Revision: http://reviews.llvm.org/D7735
llvm-svn: 229820
This is just a single commit that includes a performance optimization that
should improve dependence analysis time. Our performance bots should measure
this difference.
llvm-svn: 229476
This commit imports the latest isl version into lib/External/isl. The changes
relavant for Polly are:
1) Schedule trees [1] have been introduced as a more structured way to
describe schedules. Polly does not yet use them, but we may switch to them
in the near future.
2) Another set of coalescing changes [2] simplifies some data dependences and
removes a couple of code generation artifacts.
We now understand that the following sets can be merged:
{ Stmt_S1[i0, i1] -> Stmt_S2[i0 + i1] :
i0 >= 0 and i1 <= 1023 - i0 and i1 >= 1
Stmt_S1[i0, 0] -> Stmt_S2[i0] : i0 <= 1023 and i0 >= 1}
into:
{ Stmt_S1[i0, i1] -> Stmt_S2[i0 + i1] : i1 <= 1023 - i0 and i1 >= 0 and
i1 >= 1 - i0 and i0 >= 0 }
Changes of this kind reduce unnecessary specialization during code
generation.
- for (int c3 = 0; c3 <= 1023; c3 += 1) {
- if (c3 % 2 == 0) {
- Stmt_for_body3(c1, c3);
- } else
- Stmt_for_body3(c1, c3);
- }
+ for (int c3 = 0; c3 <= 1023; c3 += 1)
+ Stmt_for_body3(c1, c3);
[1] http://impact.gforge.inria.fr/impact2014/papers/impact2014-verdoolaege.pdf
[2] http://impact.gforge.inria.fr/impact2015/papers/impact2015-verdoolaege.pdf
llvm-svn: 229423
Alias checks might become costly if there are divisions that complicate the
description of the accessed locations. By overaproximating them we get fairly
accurate results without the huge compile time cost.
llvm-svn: 229252
namespace and header rather than the top-level header and using
declarations. These helpers impede modular builds and are going away.
Migrating away from them will also be necessary to start mixing in any
usage of the new pass manager.
llvm-svn: 229091
Without this change we get linker errors such as:
undefined reference to `llvm::dbgs()'
We only conditionally link in these libraries, as in BUILD_SHARED_LIBS=OFF mode,
linking in these libraries causes such functions (and especially global options)
to be defined twice. The "solution" I choose is most likely not ideal, but seems
to work. If any cmake specialist can suggest a better approach, this would be
appreciated.
We also drop a .c file that is not needed as it caused linker errors as well.
llvm-svn: 228914
This allows us to skip ast and code generation if we did not optimize
a SCoP and will not generate parallel or alias annotations. The
initial heuristic to exit is simple but allows improvements later on.
All failing test cases have been modified to disable early exit, thus
to keep their coverage.
Differential Revision: http://reviews.llvm.org/D7254
llvm-svn: 228851
These write are important as they will force the scheduling and code
generation of an otherwise trivial statement and also impose an order of
execution needed to guarantee the correct final value for a scalar in a loop.
Added test case modeled after ClamAV/clamscan.
llvm-svn: 228847
This change has two main purposes:
1) We do not use a static interface to hide an object we create and
destroy for every basic block we copy.
2) We allow the BlockGenerator to store information between calls to
the copyBB method. This will ease scalar/phi code generation
later on.
While a lot of method signatures were changed this should not cause
any real behaviour change.
Differential Revision: http://reviews.llvm.org/D7467
llvm-svn: 228443
This allows us to model PHI nodes in the polyhedral description
without demoting them. The modeling however will result in the
same accesses as the demotion would have introduced.
Differential Revision: http://reviews.llvm.org/D7415
llvm-svn: 228433
With this patch Polly is always GPL-free (no dependency on GMP any more). As a
result, building and distributing Polly will be easier. Furthermore, there is no
need to tightly coordinate isl and Polly releases anymore.
We import isl b3e0fa7a05d as well as imath 4d707e5ef2. These are the git
versions Polly currently was tested with when using utils/checkout_isl.sh. The
imported libraries are both MIT-style licensed.
We build isl and imath with -fvisibility=hidden to avoid clashes in case other
projects (such as gcc) use conflicting versions of isl. The use of imath can
temporarily reduce compile-time performance of Polly. We will work on
performance tuning in tree.
Patches to isl should be contributed first to the main isl repository and can
then later be reimported to Polly.
This patch is also a prerequisite for the upcoming isl C++ interface.
llvm-svn: 228193