commit cad5d87f22232fabada8dfb0f030c0cdcfbfdea5
author Mikhail Dvorskiy <mikhail.dvorskiy@intel.com> Wed Oct 27 18:51:36 2021 +0300
committer Copybara-Service <copybara-worker@google.com> Wed Oct 27 08:57:30 2021 -0700
tree 3451a3f4b376217e556a1b223957322778313366
parent 18d108edfa9200f1e1db832ddf1e2ba3f60e437b

[pstl] A hot fix for a reduction parallel pattern of OpenMP backend

Reviewed By: nadiasvertex, ldionne

Differential Revision: https://reviews.llvm.org/D112125

GitOrigin-RevId: 8f5cb64c7147c27953933dbaea107454ff066ed1

include/pstl/internal/omp/parallel_reduce.h

diff --git a/include/pstl/internal/omp/parallel_reduce.h b/include/pstl/internal/omp/parallel_reduce.h
index 71fc8a2..f0b5afc 100644
--- a/include/pstl/internal/omp/parallel_reduce.h
+++ b/include/pstl/internal/omp/parallel_reduce.h
@@ -23,6 +23,11 @@
 __parallel_reduce_body(_RandomAccessIterator __first, _RandomAccessIterator __last, _Value __identity,
                        _RealBody __real_body, _Reduction __reduce)
 {
+    if (__should_run_serial(__first, __last))
+    {
+        return __real_body(__first, __last, __identity);
+    }
+
     auto __middle = __first + ((__last - __first) / 2);
     _Value __v1(__identity), __v2(__identity);
     __parallel_invoke_body(