[INFRA] Import NVIDIA/CCCL upstream as optimization reference library

CCCL (CUDA C++ Core Libraries) provides:
- CUB: device/block/warp-level GPU primitives (reduce, scan, sort, topk)
- Thrust: high-level parallel algorithms (transform_reduce, sort, scan)
- libcudacxx: CUDA C++ standard library (atomics, barriers, memory)
- cudax: experimental features (memory resources, allocators)
- Tuning policies: per-SM hardware-specific algorithm parameters

Competition optimization vectors mapped to CCCL:
- Output TPS (83% weight): warp_reduce, block_reduce, device_topk
- Input TPS (14% weight): device_scan, block_load, prefetch
- Cache TPS (3% weight): prefix caching strategy patterns
- Memory (0.9 util): pooled/cached/buddy allocators

Source: https://github.com/NVIDIA/cccl (shallow clone, HEAD only)
License: Apache-2.0

cccl_upstream/thrust/testing/reverse.cu

@@ -0,0 +1,171 @@
+#include <thrust/iterator/discard_iterator.h>
+#include <thrust/iterator/retag.h>
+#include <thrust/reverse.h>
+
+#include <unittest/unittest.h>
+
+using ReverseTypes = unittest::type_list<unittest::int8_t, unittest::int16_t, unittest::int32_t>;
+
+template <typename Vector>
+void TestReverseSimple()
+{
+  Vector data{1, 2, 3, 4, 5};
+
+  thrust::reverse(data.begin(), data.end());
+
+  Vector ref{5, 4, 3, 2, 1};
+
+  ASSERT_EQUAL(ref, data);
+}
+DECLARE_VECTOR_UNITTEST(TestReverseSimple);
+
+template <typename BidirectionalIterator>
+void reverse(my_system& system, BidirectionalIterator, BidirectionalIterator)
+{
+  system.validate_dispatch();
+}
+
+void TestReverseDispatchExplicit()
+{
+  thrust::device_vector<int> vec(1);
+
+  my_system sys(0);
+  thrust::reverse(sys, vec.begin(), vec.begin());
+
+  ASSERT_EQUAL(true, sys.is_valid());
+}
+DECLARE_UNITTEST(TestReverseDispatchExplicit);
+
+template <typename BidirectionalIterator>
+void reverse(my_tag, BidirectionalIterator first, BidirectionalIterator)
+{
+  *first = 13;
+}
+
+void TestReverseDispatchImplicit()
+{
+  thrust::device_vector<int> vec(1);
+
+  thrust::reverse(thrust::retag<my_tag>(vec.begin()), thrust::retag<my_tag>(vec.begin()));
+
+  ASSERT_EQUAL(13, vec.front());
+}
+DECLARE_UNITTEST(TestReverseDispatchImplicit);
+
+template <typename Vector>
+void TestReverseCopySimple()
+{
+#if _CCCL_COMPILER(GCC, >=, 8) && _CCCL_COMPILER(GCC, <, 10)
+
+  if (typeid(Vector) == typeid(thrust::host_vector<custom_numeric>))
+  {
+    KNOWN_FAILURE // WAR NVBug 2481122
+  }
+#endif // _CCCL_COMPILER(GCC, >=, 8) && _CCCL_COMPILER(GCC, <, 10)
+
+  using Iterator = typename Vector::iterator;
+
+  Vector input{1, 2, 3, 4, 5};
+  Vector output(8); // arm GCC is complaining about destination size
+
+  Iterator iter = thrust::reverse_copy(input.begin(), input.end(), output.begin());
+
+  output.resize(5);
+  Vector ref{5, 4, 3, 2, 1};
+  ASSERT_EQUAL(5, iter - output.begin());
+  ASSERT_EQUAL(ref, output);
+}
+DECLARE_VECTOR_UNITTEST(TestReverseCopySimple);
+
+template <typename BidirectionalIterator, typename OutputIterator>
+OutputIterator reverse_copy(my_system& system, BidirectionalIterator, BidirectionalIterator, OutputIterator result)
+{
+  system.validate_dispatch();
+  return result;
+}
+
+void TestReverseCopyDispatchExplicit()
+{
+  thrust::device_vector<int> vec(1);
+
+  my_system sys(0);
+  thrust::reverse_copy(sys, vec.begin(), vec.end(), vec.begin());
+
+  ASSERT_EQUAL(true, sys.is_valid());
+}
+DECLARE_UNITTEST(TestReverseCopyDispatchExplicit);
+
+template <typename BidirectionalIterator, typename OutputIterator>
+OutputIterator reverse_copy(my_tag, BidirectionalIterator, BidirectionalIterator, OutputIterator result)
+{
+  *result = 13;
+  return result;
+}
+
+void TestReverseCopyDispatchImplicit()
+{
+  thrust::device_vector<int> vec(1);
+
+  thrust::reverse_copy(
+    thrust::retag<my_tag>(vec.begin()), thrust::retag<my_tag>(vec.end()), thrust::retag<my_tag>(vec.begin()));
+
+  ASSERT_EQUAL(13, vec.front());
+}
+DECLARE_UNITTEST(TestReverseCopyDispatchImplicit);
+
+template <typename T>
+struct TestReverse
+{
+  void operator()(const size_t n)
+  {
+    thrust::host_vector<T> h_data   = unittest::random_integers<T>(n);
+    thrust::device_vector<T> d_data = h_data;
+
+    thrust::reverse(h_data.begin(), h_data.end());
+    thrust::reverse(d_data.begin(), d_data.end());
+
+    ASSERT_EQUAL(h_data, d_data);
+  }
+};
+VariableUnitTest<TestReverse, ReverseTypes> TestReverseInstance;
+
+template <typename T>
+struct TestReverseCopy
+{
+  void operator()(const size_t n)
+  {
+    thrust::host_vector<T> h_data   = unittest::random_integers<T>(n);
+    thrust::device_vector<T> d_data = h_data;
+
+    thrust::host_vector<T> h_result(n);
+    thrust::device_vector<T> d_result(n);
+
+    thrust::reverse_copy(h_data.begin(), h_data.end(), h_result.begin());
+    thrust::reverse_copy(d_data.begin(), d_data.end(), d_result.begin());
+
+    ASSERT_EQUAL(h_result, d_result);
+  }
+};
+VariableUnitTest<TestReverseCopy, ReverseTypes> TestReverseCopyInstance;
+
+template <typename T>
+struct TestReverseCopyToDiscardIterator
+{
+  void operator()(const size_t n)
+  {
+    thrust::host_vector<T> h_data   = unittest::random_integers<T>(n);
+    thrust::device_vector<T> d_data = h_data;
+
+    thrust::discard_iterator<> h_result =
+      thrust::reverse_copy(h_data.begin(), h_data.end(), thrust::make_discard_iterator());
+
+    thrust::discard_iterator<> d_result =
+      thrust::reverse_copy(d_data.begin(), d_data.end(), thrust::make_discard_iterator());
+
+    thrust::discard_iterator<> reference(static_cast<std::ptrdiff_t>(n));
+
+    ASSERT_EQUAL_QUIET(reference, h_result);
+    ASSERT_EQUAL_QUIET(reference, d_result);
+  }
+};
+VariableUnitTest<TestReverseCopyToDiscardIterator, ReverseTypes> TestReverseCopyToDiscardIteratorInstance;