Robustness testing: AOSP and FFMPEG¶

Polly can now compile all of Android. While most of Android is not the primary target of polyhedral data locality optimizations, Android provides us with a large and diverse set of robustness tests. Our new nightly build bot ensures we do not regress.

Polly also successfully compiles FFMPEG and obviously the LLVM test suite.

C++ bindings for isl math library improve maintainability¶

In the context of Polly Labs, a new set of C++ bindings was developed for the isl math library. Thanks to the new isl C++ interface there is no need for manual memory management any more and programming with integer sets became easier in general.

Today:

void isDiffEmptyOrUnionTheUniverse(isl::set S1, isl::set S2) {
  isl::set Difference = S1.subtract(S2);
  isl::set Union = S1.unite(S2);

  if (Difference.is_empty())
    return true;

  if (Union.is_universe())
    return true;

  return false;
}

Before:

void isDiffEmptyOrUnionTheUniverse(__isl_take isl_set S1,
                                   __isl_take isl_set S2) {
  isl_set *Difference = isl_set_subtract(isl_set_copy(S1),
                                         isl_set_copy(S2));

  isl_set *Union = isl_set_union(S1, S2);

  isl_bool IsEmpty = isl_set_is_empty(Difference);
  isl_set_free(Difference);

  if (IsEmpty == isl_bool_error)
    llvm_unreachable();

  if (IsEmpty)
    return true;

  isl_bool IsUniverse = isl_set_is_Universe(Union);
  isl_set_free(Union);

  if (IsUniverse == isl_bool_error)
    llvm_unreachable();

  if (IsUniverse)
    return true;

  return false;
}

Improved Polly Diagnostics¶

Polly now uses the LLVM OptimizationDiagnosticInfo API for emitting diagnostic remarks. This allows Polly remarks to appear in the yaml optimization record when compiling with the flag -fsave-optimization-record. This also allows Polly remarks to appear in the opt-viewer tool, allowing for remarks to be viewed next to the source code, and sorted by hotness.

Polly-ACC works with Julia¶

Polly can now offload Julia to GPUs. This feature is enabled by setting the USE_POLLY_ACC variable to 1, i.e. USE_POLLY_ACC:=1.