Model statement wise reduction dependences

+ Collect reduction dependences
+ Introduced TYPE_RED in Dependences.h which can be used to obtain the
  reduction dependences
+ Used TYPE_RED to prevent parallelization while we do not have a privatizing
  code generation
+ Relax the dependences for non-parallel code generation
+ Add privatization dependences to ensure correctness
+ 12 Test cases to check for reduction and privatization dependences

llvm-svn: 211369

1 files changed, 3 insertions, 1 deletions

diff --git a/polly/lib/CodeGen/IslAst.cpp b/polly/lib/CodeGen/IslAst.cpp
index 0e2ddcc72b6..57814e4464a 100644
--- a/polly/lib/CodeGen/IslAst.cpp
+++ b/polly/lib/CodeGen/IslAst.cpp
@@ -166,7 +166,9 @@ static bool astScheduleDimIsParallel(__isl_keep isl_ast_build *Build,
 
   Dimension = isl_space_dim(ScheduleSpace, isl_dim_out) - 1;
 
-  Deps = D->getDependences(Dependences::TYPE_ALL);
+  // FIXME: We can remove ignore reduction dependences in case we privatize the
+  //        memory locations the reduction statements reduce into.
+  Deps = D->getDependences(Dependences::TYPE_ALL | Dependences::TYPE_RED);
   Deps = isl_union_map_apply_range(Deps, isl_union_map_copy(Schedule));
   Deps = isl_union_map_apply_domain(Deps, Schedule);