Commit Graph

3 Commits

Author SHA1 Message Date
Tobias Grosser e395da7986 Update isl to 0980603 'isl_tab_pip.c: parallel_constraints: drop useless assignment'
This update contains:

  - Fixes of minor issues detected by clang's scan_build
  - More schedule tree infrastructure additions

This update slightly changes the output of our dependence analysis, but these
changes are purely syntactially.

llvm-svn: 230528
2015-02-25 19:34:52 +00:00
Tobias Grosser 1fa7b972c0 Update to isl 99d53692ba
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
2015-02-16 19:33:40 +00:00
Tobias Grosser 52a25237d8 Import isl(+imath) as an external library into Polly
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
2015-02-04 20:55:43 +00:00