Merge branch 'embb392_partitioner' into development

algorithms_cpp/include/embb/algorithms/internal/partition-inl.h

@@ -31,109 +31,104 @@ namespace embb {
 namespace algorithms {
 namespace internal {
 
-template<typename ForwardIterator>
-ChunkDescriptor<ForwardIterator>::ChunkDescriptor(ForwardIterator first,
-    ForwardIterator last) :
-    first(first), last(last) {
+template<typename RAI>
+ChunkDescriptor<RAI>::ChunkDescriptor(
+  RAI first, RAI last) :
+  first_(first), last_(last) {
 }
 
-template<typename ForwardIterator>
-ForwardIterator ChunkDescriptor<ForwardIterator>::GetFirst() const {
-  return first;
+template<typename RAI>
+RAI ChunkDescriptor<RAI>::GetFirst() const {
+  return first_;
 }
 
-template<typename ForwardIterator>
-ForwardIterator ChunkDescriptor<ForwardIterator>::GetLast() const {
-  return last;
+template<typename RAI>
+RAI ChunkDescriptor<RAI>::GetLast() const {
+  return last_;
 }
 
-template<typename ForwardIterator>
-BlockSizePartitioner<ForwardIterator>::BlockSizePartitioner(
-    ForwardIterator first, ForwardIterator last, size_t chunkSize) :
-    first(first), last(last), chunkSize(chunkSize) {
-  elements_count = static_cast<size_t>(std::distance(first, last));
-  chunks = elements_count / chunkSize;
-  if (elements_count % chunkSize != 0)
-    chunks++;
+template<typename RAI>
+BlockSizePartitioner<RAI>::BlockSizePartitioner(
+    RAI first, RAI last, size_t chunkSize) :
+    first_(first), last_(last), chunk_size_(chunkSize) {
+  elements_count_ = static_cast<size_t>(std::distance(first_, last_));
+  chunks_ = elements_count_ / chunk_size_;
+  if (elements_count_ % chunk_size_ != 0) {
+    chunks_++;
+  }
 }
 
-template<typename ForwardIterator>
-size_t BlockSizePartitioner<ForwardIterator>::Size() {
-  return chunks;
+template<typename RAI>
+size_t BlockSizePartitioner<RAI>::Size() {
+  return chunks_;
 }
 
-template<typename ForwardIterator>
-const ChunkDescriptor<ForwardIterator>
-  BlockSizePartitioner<ForwardIterator>::operator[](
-    size_t const& index) const {
-  ForwardIterator first_new = first;
-  std::advance(first_new, index * chunkSize);
-
-  ForwardIterator last_new = first_new;
-
-  if (index >= chunks - 1) {
-    last_new = last;
+template<typename RAI>
+const ChunkDescriptor<RAI>
+  BlockSizePartitioner<RAI>::operator[](
+    size_t const & index) const {
+  typedef typename std::iterator_traits<RAI>::difference_type
+    difference_type;
+  RAI first_new(first_);
+  first_new += static_cast<difference_type>(chunk_size_ * index);
+  RAI last_new(first_new);
+  if (index >= chunks_ - 1) {
+    last_new = last_;
   } else {
-    std::advance(last_new, chunkSize);
+    last_new += static_cast<difference_type>(chunk_size_);
   }
-
-  return ChunkDescriptor<ForwardIterator>(first_new, last_new);
+  return ChunkDescriptor<RAI>(first_new, last_new);
 }
 
-template<typename ForwardIterator>
-size_t ChunkPartitioner<ForwardIterator>::Size() {
-  return size;
+template<typename RAI>
+size_t ChunkPartitioner<RAI>::Size() {
+  return size_;
 }
 
-template<typename ForwardIterator>
-ChunkPartitioner<ForwardIterator>::ChunkPartitioner(ForwardIterator first,
-    ForwardIterator last, size_t amountChunks) :
-    first(first), last(last) {
+template<typename RAI>
+ChunkPartitioner<RAI>::ChunkPartitioner(
+  RAI first, RAI last, size_t amountChunks) :
+  first_(first), last_(last) {
   if (amountChunks > 0) {
-    size = amountChunks;
+    size_ = amountChunks;
   } else {
-    // if no concrete chunk size was given, use number of cores...
+    // if no concrete chunk size was given, use number of cores
     embb::tasks::Node& node = embb::tasks::Node::GetInstance();
-    size = node.GetWorkerThreadCount();
+    size_ = node.GetWorkerThreadCount();
   }
-
-  elements_count = static_cast<size_t>(std::distance(first, last));
-  if (size > elements_count) {
+  elements_count_ = static_cast<size_t>(std::distance(first_, last_));
+  if (size_ > elements_count_) {
     // if we want to make more chunks than we have elements, correct
     // the number of chunks
-    size = elements_count;
+    size_ = elements_count_;
   }
-  standard_chunk_size = elements_count / size;
-  bigger_chunk_count = elements_count % size;
+  standard_chunk_size_ = elements_count_ / size_;
+  bigger_chunk_count_  = elements_count_ % size_;
 }
 
-template<typename ForwardIterator>
-const ChunkDescriptor<ForwardIterator>
-  ChunkPartitioner<ForwardIterator>::operator[](
+template<typename RAI>
+const ChunkDescriptor<RAI>
+  ChunkPartitioner<RAI>::operator[](
     size_t const& index) const {
-  typedef typename std::iterator_traits<ForwardIterator>::difference_type
+  typedef typename std::iterator_traits<RAI>::difference_type
       difference_type;
+  // Number of element preceding elements in the given chunk
   size_t prec_elements_count = 0;
-
-  if (index <= bigger_chunk_count) {
-    prec_elements_count = index * (standard_chunk_size + 1);
+  if (index <= bigger_chunk_count_) {
+    prec_elements_count = index * (standard_chunk_size_ + 1);
   } else {
-    prec_elements_count = (standard_chunk_size + 1) * bigger_chunk_count
-        + standard_chunk_size * (index - bigger_chunk_count);
+    prec_elements_count =
+      (standard_chunk_size_ + 1) * bigger_chunk_count_ +
+      (standard_chunk_size_ * (index - bigger_chunk_count_));
   }
-
-  size_t cur_elements_count =
-      (index < bigger_chunk_count) ?
-          (standard_chunk_size + 1) : standard_chunk_size;
-
-  ForwardIterator first_new = first;
-  std::advance(first_new, prec_elements_count);
-
-  first_new = first + static_cast<difference_type>(prec_elements_count);
-  ForwardIterator last_new = first_new;
-  std::advance(last_new, cur_elements_count);
-
-  return ChunkDescriptor<ForwardIterator>(first_new, last_new);
+  size_t cur_elements_count = (index < bigger_chunk_count_)
+           ? (standard_chunk_size_ + 1)
+           : standard_chunk_size_;
+  RAI first_new(first_);
+  first_new += static_cast<difference_type>(prec_elements_count);
+  RAI last_new(first_new);
+  last_new += static_cast<difference_type>(cur_elements_count);
+  return ChunkDescriptor<RAI>(first_new, last_new);
 }
 
 }  // namespace internal

algorithms_cpp/include/embb/algorithms/internal/partition.h

@@ -38,14 +38,14 @@ namespace internal {
  * Describes a single partition of a 1-dimensional
  * partitioning, using first and last iterator.
  *
- * \tparam  ForwardIterator  Type of the iterator.
+ * \tparam  RAI  Type of the iterator.
  */
 
-template<typename ForwardIterator>
+template<typename RAI>
 class ChunkDescriptor {
  private:
-  ForwardIterator first;
-  ForwardIterator last;
+  RAI first_;
+  RAI last_;
 
  public:
   /**
@@ -54,7 +54,7 @@ class ChunkDescriptor {
    * \param first The first iterator.
    * \param last  The last iterator
    */
-  ChunkDescriptor(ForwardIterator first, ForwardIterator last);
+  ChunkDescriptor(RAI first, RAI last);
 
   /**
    * Gets the first iterator.
@@ -63,7 +63,7 @@ class ChunkDescriptor {
    * 
    * \waitfree
    */
-  ForwardIterator GetFirst() const;
+  RAI GetFirst() const;
 
   /**
    * Gets the last iterator.
@@ -72,7 +72,7 @@ class ChunkDescriptor {
    * 
    * \waitfree
    */
-  ForwardIterator GetLast() const;
+  RAI GetLast() const;
 };
 
 /**
@@ -80,9 +80,9 @@ class ChunkDescriptor {
  *        
  * Describes the interface for accessing a 1-dimensional partitioning. 
  *
- * \tparam  ForwardIterator  Type of the iterator.
+ * \tparam  RAI  Type of the iterator.
  */
-template<typename ForwardIterator>
+template<typename RAI>
 class IPartitioner {
  public:
   virtual ~IPartitioner() {}
@@ -106,7 +106,7 @@ class IPartitioner {
    * 
    * \waitfree
    */
-  virtual const ChunkDescriptor<ForwardIterator> operator[](
+  virtual const ChunkDescriptor<RAI> operator[](
     size_t const& index) const = 0;
 };
 
@@ -129,16 +129,16 @@ class IPartitioner {
  *    2: [6,7,8,9,10]  
  *    3: [11,12,13]
  * 
- * \tparam  ForwardIterator  Type of the iterator.
+ * \tparam  RAI  Type of the iterator.
  */
-template<typename ForwardIterator>
-class BlockSizePartitioner : IPartitioner < ForwardIterator > {
+template<typename RAI>
+class BlockSizePartitioner : IPartitioner < RAI > {
  private:
-  ForwardIterator first;
-  ForwardIterator last;
-  size_t chunkSize;
-  size_t elements_count;
-  size_t chunks;
+  RAI first_;
+  RAI last_;
+  size_t chunk_size_;
+  size_t elements_count_;
+  size_t chunks_;
 
  public:
   /**
@@ -150,7 +150,7 @@ class BlockSizePartitioner : IPartitioner < ForwardIterator > {
    * \param chunkSize (Optional) size of the chunk.
    */
   BlockSizePartitioner(
-    ForwardIterator first, ForwardIterator last, size_t chunkSize = 1);
+    RAI first, RAI last, size_t chunkSize = 1);
 
   /**
    * See IPartitioner
@@ -164,7 +164,7 @@ class BlockSizePartitioner : IPartitioner < ForwardIterator > {
    *
    * \waitfree
    */
-  virtual const ChunkDescriptor<ForwardIterator> operator[](
+  virtual const ChunkDescriptor<RAI> operator[](
     size_t const& index) const;
 };
 
@@ -196,17 +196,17 @@ class BlockSizePartitioner : IPartitioner < ForwardIterator > {
  * 4: [10,11]  
  * 5: [12,13]   
  *  
- * \tparam  ForwardIterator  Type of the iterator.
+ * \tparam  RAI  Type of the iterator.
  */
-template<typename ForwardIterator>
-class ChunkPartitioner : IPartitioner < ForwardIterator > {
+template<typename RAI>
+class ChunkPartitioner : IPartitioner < RAI > {
  private:
-  size_t size;
-  size_t elements_count;
-  ForwardIterator first;
-  ForwardIterator last;
-  size_t standard_chunk_size;
-  size_t bigger_chunk_count;
+  size_t size_;
+  size_t elements_count_;
+  RAI first_;
+  RAI last_;
+  size_t standard_chunk_size_;
+  size_t bigger_chunk_count_;
 
  public:
   /**
@@ -227,7 +227,7 @@ class ChunkPartitioner : IPartitioner < ForwardIterator > {
    * \param last           The last.
    * \param amountChunks  (Optional) the amount chunks.
    */
-  ChunkPartitioner(ForwardIterator first, ForwardIterator last,
+  ChunkPartitioner(RAI first, RAI last,
     size_t amountChunks = 0);
 
   /**
@@ -235,7 +235,7 @@ class ChunkPartitioner : IPartitioner < ForwardIterator > {
    *
    * \waitfree
    */
-  virtual const ChunkDescriptor<ForwardIterator> operator[](
+  virtual const ChunkDescriptor<RAI> operator[](
     size_t const& index) const;
 };
 

algorithms_cpp/test/partitioner_test.cc

@@ -33,9 +33,15 @@
 #include <vector>
 #include <list>
 
-PartitionerTest::PartitionerTest() {
-  CreateUnit("algorithms partitioner test").
-  Add(&PartitionerTest::TestBasic, this);
+PartitionerTest::PartitionerTest()
+: partitioned_array_size_(16384) {
+  // Size of array to be partitioned should be power of 2
+  CreateUnit("TestBasic")
+    .Add(&PartitionerTest::TestBasic, this);
+  CreateUnit("TestLargeRange")
+    .Pre(&PartitionerTest::TestLargeRangePre, this)
+    .Add(&PartitionerTest::TestLargeRange, this)
+    .Post(&PartitionerTest::TestLargeRangePost, this);
 }
 
 void PartitionerTest::TestBasic() {
@@ -70,3 +76,62 @@ void PartitionerTest::TestBasic() {
   PT_EXPECT_EQ_MSG(partitioner2.Size(), size_t(3), "Check count of partitions");
 }
 
+void PartitionerTest::TestLargeRangePre() {
+  partitioned_array_ = new int[partitioned_array_size_];
+  for (size_t i = 0; i < partitioned_array_size_; ++i) {
+    partitioned_array_[i] = static_cast<int>(i);
+  }
+}
+
+void PartitionerTest::TestLargeRangePost() {
+  delete[] partitioned_array_;
+}
+
+void PartitionerTest::TestLargeRange() {
+  // Test chunk partitioner with increasing number of chunks:
+  for (size_t num_chunks = 2;
+       num_chunks < partitioned_array_size_;
+       num_chunks *= 2) {
+    embb::algorithms::internal::ChunkPartitioner<int *>
+      chunk_partitioner(
+      partitioned_array_,
+      partitioned_array_ + partitioned_array_size_,
+      num_chunks);
+    int last_value_prev = -1;
+    PT_EXPECT_EQ(num_chunks, chunk_partitioner.Size());
+    // Iterate over chunks in partition:
+    for (size_t chunk = 0; chunk < chunk_partitioner.Size(); ++chunk) {
+      int first_value = *(chunk_partitioner[chunk].GetFirst());
+      int last_value  = *(chunk_partitioner[chunk].GetLast() - 1);
+      PT_EXPECT_LT(first_value, last_value);
+      // Test seams between chunks: chunk[i].last + 1 == chunk[i+1].first
+      PT_EXPECT_EQ((last_value_prev + 1), first_value);
+      last_value_prev = last_value;
+    }
+  }
+  // Test block size partitioner with increasing chunk size:
+  for (size_t block_size = 1;
+       block_size < partitioned_array_size_;
+       block_size *= 2) {
+    embb::algorithms::internal::BlockSizePartitioner<int *>
+      chunk_partitioner(
+      partitioned_array_,
+      partitioned_array_ + partitioned_array_size_,
+      block_size);
+    int last_value_prev = -1;
+    // Iterate over chunks in partition:
+    for (size_t chunk = 0; chunk < chunk_partitioner.Size(); ++chunk) {
+      int first_value = *(chunk_partitioner[chunk].GetFirst());
+      int last_value  = *(chunk_partitioner[chunk].GetLast() - 1);
+      if (block_size == 1) {
+        PT_EXPECT_EQ(first_value, last_value);
+      } else {
+        PT_EXPECT_LT(first_value, last_value);
+      }
+      // Test seams between chunks: chunk[i].last + 1 == chunk[i+1].first
+      PT_EXPECT_EQ((last_value_prev + 1), first_value);
+      last_value_prev = last_value;
+    }
+  }
+}
+

algorithms_cpp/test/partitioner_test.h

@@ -35,6 +35,13 @@ class PartitionerTest : public partest::TestCase {
 
  private:
   void TestBasic();
+
+  void TestLargeRangePre();
+  void TestLargeRangePost();
+  void TestLargeRange();
+
+  int * partitioned_array_;
+  size_t partitioned_array_size_;
 };
 
 #endif  // ALGORITHMS_CPP_TEST_PARTITIONER_TEST_H_