From 9de155d15320a68182e7f572adf504cad6172419 Mon Sep 17 00:00:00 2001
From: Benoit Steiner <benoit.steiner.goog@gmail.com>
Date: Sat, 30 Jan 2016 10:56:47 -0800
Subject: [PATCH] Added a test to cover threaded tensor shuffling

---
 unsupported/test/cxx11_tensor_thread_pool.cpp | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/unsupported/test/cxx11_tensor_thread_pool.cpp b/unsupported/test/cxx11_tensor_thread_pool.cpp
index aa76009b7..e46197464 100644
--- a/unsupported/test/cxx11_tensor_thread_pool.cpp
+++ b/unsupported/test/cxx11_tensor_thread_pool.cpp
@@ -283,6 +283,31 @@ void test_multithread_random()
   t.device(device) = t.random<Eigen::internal::NormalRandomGenerator<float>>();
 }
 
+template<int DataLayout>
+void test_multithread_shuffle()
+{
+  Tensor<float, 4, DataLayout> tensor(17,5,7,11);
+  tensor.setRandom();
+
+  const int num_threads = internal::random<int>(2, 11);
+  ThreadPool threads(num_threads);
+  Eigen::ThreadPoolDevice device(&threads, num_threads);
+
+  Tensor<float, 4, DataLayout> shuffle(7,5,11,17);
+  array<ptrdiff_t, 4> shuffles = {{2,1,3,0}};
+  shuffle.device(device) = tensor.shuffle(shuffles);
+
+  for (int i = 0; i < 17; ++i) {
+    for (int j = 0; j < 5; ++j) {
+      for (int k = 0; k < 7; ++k) {
+        for (int l = 0; l < 11; ++l) {
+          VERIFY_IS_EQUAL(tensor(i,j,k,l), shuffle(k,j,l,i));
+        }
+      }
+    }
+  }
+}
+
 
 void test_cxx11_tensor_thread_pool()
 {
@@ -304,4 +329,6 @@ void test_cxx11_tensor_thread_pool()
 
   CALL_SUBTEST_6(test_memcpy());
   CALL_SUBTEST_6(test_multithread_random());
+  CALL_SUBTEST_6(test_multithread_shuffle<ColMajor>());
+  CALL_SUBTEST_6(test_multithread_shuffle<RowMajor>());
 }