[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/cuda/equal.cu

@@ -0,0 +1,120 @@
+#include <thrust/equal.h>
+#include <thrust/execution_policy.h>
+#include <thrust/functional.h>
+
+#include <unittest/unittest.h>
+
+#ifdef THRUST_TEST_DEVICE_SIDE
+template <typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename Iterator3>
+__global__ void equal_kernel(ExecutionPolicy exec, Iterator1 first1, Iterator1 last1, Iterator2 first2, Iterator3 result)
+{
+  *result = thrust::equal(exec, first1, last1, first2);
+}
+
+template <typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename BinaryPredicate, typename Iterator3>
+__global__ void equal_kernel(
+  ExecutionPolicy exec, Iterator1 first1, Iterator1 last1, Iterator2 first2, BinaryPredicate pred, Iterator3 result)
+{
+  *result = thrust::equal(exec, first1, last1, first2, pred);
+}
+
+template <typename T, typename ExecutionPolicy>
+void TestEqualDevice(ExecutionPolicy exec, const size_t n)
+{
+  thrust::device_vector<T> d_data1 = unittest::random_samples<T>(n);
+  thrust::device_vector<T> d_data2 = unittest::random_samples<T>(n);
+  thrust::device_vector<bool> d_result(1, false);
+
+  // empty ranges
+  equal_kernel<<<1, 1>>>(exec, d_data1.begin(), d_data1.begin(), d_data1.begin(), d_result.begin());
+  {
+    cudaError_t const err = cudaDeviceSynchronize();
+    ASSERT_EQUAL(cudaSuccess, err);
+  }
+
+  ASSERT_EQUAL(d_result[0], true);
+
+  // symmetric cases
+  equal_kernel<<<1, 1>>>(exec, d_data1.begin(), d_data1.end(), d_data1.begin(), d_result.begin());
+  {
+    cudaError_t const err = cudaDeviceSynchronize();
+    ASSERT_EQUAL(cudaSuccess, err);
+  }
+
+  ASSERT_EQUAL(d_result[0], true);
+
+  if (n > 0)
+  {
+    d_data1[0] = 0;
+    d_data2[0] = 1;
+
+    // different vectors
+    equal_kernel<<<1, 1>>>(exec, d_data1.begin(), d_data1.end(), d_data2.begin(), d_result.begin());
+    {
+      cudaError_t const err = cudaDeviceSynchronize();
+      ASSERT_EQUAL(cudaSuccess, err);
+    }
+
+    ASSERT_EQUAL(d_result[0], false);
+
+    // different predicates
+    equal_kernel<<<1, 1>>>(
+      exec, d_data1.begin(), d_data1.begin() + 1, d_data2.begin(), ::cuda::std::less<T>(), d_result.begin());
+    {
+      cudaError_t const err = cudaDeviceSynchronize();
+      ASSERT_EQUAL(cudaSuccess, err);
+    }
+
+    ASSERT_EQUAL(d_result[0], true);
+
+    equal_kernel<<<1, 1>>>(
+      exec, d_data1.begin(), d_data1.begin() + 1, d_data2.begin(), ::cuda::std::greater<T>(), d_result.begin());
+    {
+      cudaError_t const err = cudaDeviceSynchronize();
+      ASSERT_EQUAL(cudaSuccess, err);
+    }
+
+    ASSERT_EQUAL(d_result[0], false);
+  }
+}
+
+template <typename T>
+void TestEqualDeviceSeq(const size_t n)
+{
+  TestEqualDevice<T>(thrust::seq, n);
+}
+DECLARE_VARIABLE_UNITTEST(TestEqualDeviceSeq);
+
+template <typename T>
+void TestEqualDeviceDevice(const size_t n)
+{
+  TestEqualDevice<T>(thrust::device, n);
+}
+DECLARE_VARIABLE_UNITTEST(TestEqualDeviceDevice);
+#endif
+
+void TestEqualCudaStreams()
+{
+  thrust::device_vector<int> v1 = {5, 2, 0, 0, 0};
+  thrust::device_vector<int> v2 = {5, 2, 0, 6, 1};
+
+  cudaStream_t s;
+  cudaStreamCreate(&s);
+
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.end(), v1.begin()), true);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.end(), v2.begin()), false);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v2.begin(), v2.end(), v2.begin()), true);
+
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.begin() + 0, v1.begin()), true);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.begin() + 1, v1.begin()), true);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.begin() + 3, v2.begin()), true);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.begin() + 4, v2.begin()), false);
+
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.end(), v2.begin(), ::cuda::std::less_equal<int>()),
+               true);
+  ASSERT_EQUAL(thrust::equal(thrust::cuda::par.on(s), v1.begin(), v1.end(), v2.begin(), ::cuda::std::greater<int>()),
+               false);
+
+  cudaStreamDestroy(s);
+}
+DECLARE_UNITTEST(TestEqualCudaStreams);