/****************************************************************************** * Copyright (c) 2011, Duane Merrill. All rights reserved. * Copyright (c) 2011-2018, NVIDIA CORPORATION. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of the NVIDIA CORPORATION nor the * names of its contributors may be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ******************************************************************************/ /****************************************************************************** * Simple example of DeviceSelect::If(). * * Selects items from from a sequence of int keys using a * section functor (greater-than) * * To compile using the command line: * nvcc -arch=sm_XX example_device_select_if.cu -I../.. -lcudart -O3 * ******************************************************************************/ // Ensure printing of CUDA runtime errors to console #define CUB_STDERR #include #include #include #include "../../test/test_util.h" using namespace cub; //--------------------------------------------------------------------- // Globals, constants and typedefs //--------------------------------------------------------------------- bool g_verbose = false; // Whether to display input/output to console CachingDeviceAllocator g_allocator(true); // Caching allocator for device memory /// Selection functor type struct GreaterThan { int compare; __host__ __device__ __forceinline__ GreaterThan(int compare) : compare(compare) {} __host__ __device__ __forceinline__ bool operator()(const int &a) const { return (a > compare); } }; //--------------------------------------------------------------------- // Test generation //--------------------------------------------------------------------- /** * Initialize problem, setting runs of random length chosen from [1..max_segment] */ void Initialize( int *h_in, int num_items, int max_segment) { int key = 0; int i = 0; while (i < num_items) { // Randomly select number of repeating occurrences uniformly from [1..max_segment] unsigned short max_short = (unsigned short) -1; unsigned short repeat; RandomBits(repeat); repeat = (unsigned short) ((float(repeat) * (float(max_segment) / float(max_short)))); repeat = CUB_MAX(1, repeat); int j = i; while (j < CUB_MIN(i + repeat, num_items)) { h_in[j] = key; j++; } i = j; key++; } if (g_verbose) { printf("Input:\n"); DisplayResults(h_in, num_items); printf("\n\n"); } } /** * Solve unique problem */ template int Solve( int *h_in, SelectOp select_op, int *h_reference, int num_items) { int num_selected = 0; for (int i = 0; i < num_items; ++i) { if (select_op(h_in[i])) { h_reference[num_selected] = h_in[i]; num_selected++; } else { h_reference[num_items - (i - num_selected) - 1] = h_in[i]; } } return num_selected; } //--------------------------------------------------------------------- // Main //--------------------------------------------------------------------- /** * Main */ int main(int argc, char** argv) { int num_items = 150; int max_segment = 40; // Maximum segment length // Initialize command line CommandLineArgs args(argc, argv); g_verbose = args.CheckCmdLineFlag("v"); args.GetCmdLineArgument("n", num_items); args.GetCmdLineArgument("maxseg", max_segment); // Print usage if (args.CheckCmdLineFlag("help")) { printf("%s " "[--n= " "[--device=] " "[--maxseg=]" "[--v] " "\n", argv[0]); exit(0); } // Initialize device CubDebugExit(args.DeviceInit()); // Allocate host arrays int *h_in = new int[num_items]; int *h_reference = new int[num_items]; // Select a pivot index unsigned int pivot_index; unsigned int max_int = (unsigned int) -1; RandomBits(pivot_index); pivot_index = (unsigned int) ((float(pivot_index) * (float(num_items - 1) / float(max_int)))); printf("Pivot idx: %d\n", pivot_index); fflush(stdout); // Initialize problem and solution Initialize(h_in, num_items, max_segment); GreaterThan select_op(h_in[pivot_index]); int num_selected = Solve(h_in, select_op, h_reference, num_items); printf("cub::DeviceSelect::If %d items, %d selected (avg run length %d), %d-byte elements\n", num_items, num_selected, (num_selected > 0) ? num_items / num_selected : 0, (int) sizeof(int)); fflush(stdout); // Allocate problem device arrays int *d_in = NULL; CubDebugExit(g_allocator.DeviceAllocate((void**)&d_in, sizeof(int) * num_items)); // Initialize device input CubDebugExit(cudaMemcpy(d_in, h_in, sizeof(int) * num_items, cudaMemcpyHostToDevice)); // Allocate device output array and num selected int *d_out = NULL; int *d_num_selected_out = NULL; CubDebugExit(g_allocator.DeviceAllocate((void**)&d_out, sizeof(int) * num_items)); CubDebugExit(g_allocator.DeviceAllocate((void**)&d_num_selected_out, sizeof(int))); // Allocate temporary storage void *d_temp_storage = NULL; size_t temp_storage_bytes = 0; CubDebugExit(DeviceSelect::If(d_temp_storage, temp_storage_bytes, d_in, d_out, d_num_selected_out, num_items, select_op)); CubDebugExit(g_allocator.DeviceAllocate(&d_temp_storage, temp_storage_bytes)); // Run CubDebugExit(DeviceSelect::If(d_temp_storage, temp_storage_bytes, d_in, d_out, d_num_selected_out, num_items, select_op)); // Check for correctness (and display results, if specified) int compare = CompareDeviceResults(h_reference, d_out, num_selected, true, g_verbose); printf("\t Data %s ", compare ? "FAIL" : "PASS"); compare = compare | CompareDeviceResults(&num_selected, d_num_selected_out, 1, true, g_verbose); printf("\t Count %s ", compare ? "FAIL" : "PASS"); AssertEquals(0, compare); // Cleanup if (h_in) delete[] h_in; if (h_reference) delete[] h_reference; if (d_in) CubDebugExit(g_allocator.DeviceFree(d_in)); if (d_out) CubDebugExit(g_allocator.DeviceFree(d_out)); if (d_num_selected_out) CubDebugExit(g_allocator.DeviceFree(d_num_selected_out)); if (d_temp_storage) CubDebugExit(g_allocator.DeviceFree(d_temp_storage)); printf("\n\n"); return 0; }