Add Pair type and Boruvka's MST algorithm

CMakeLists.txt

@@ -402,6 +402,7 @@ if (SPLA_BUILD_EXAMPLES)
     spla_example_application(tc)
     spla_example_application(pi)
     spla_example_application(convert)
+    spla_example_application(mst)
 endif ()
 
 ######################################################################

examples/mst.cpp

@@ -0,0 +1,132 @@
+/**********************************************************************************/
+/* This file is part of spla project */
+/* https://github.com/SparseLinearAlgebra/spla */
+/**********************************************************************************/
+/* MIT License */
+/*                                                                                */
+/* Copyright (c) 2023 SparseLinearAlgebra */
+/*                                                                                */
+/* Permission is hereby granted, free of charge, to any person obtaining a copy
+ */
+/* of this software and associated documentation files (the "Software"), to deal
+ */
+/* in the Software without restriction, including without limitation the rights
+ */
+/* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell */
+/* copies of the Software, and to permit persons to whom the Software is */
+/* furnished to do so, subject to the following conditions: */
+/*                                                                                */
+/* The above copyright notice and this permission notice shall be included in
+ * all */
+/* copies or substantial portions of the Software. */
+/*                                                                                */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR */
+/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, */
+/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ */
+/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER */
+/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ */
+/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ */
+/* SOFTWARE. */
+/**********************************************************************************/
+
+#include "common.hpp"
+#include "options.hpp"
+
+#include <iostream>
+#include <spla.hpp>
+
+int main(int argc, const char* const* argv) {
+    auto options = make_options(
+            "mst", "Boruvka's Minimum Spanning Tree algorithm with spla library");
+
+    cxxopts::ParseResult args;
+    int                  ret;
+
+    if (parse_options(argc, argv, options, args, ret)) {
+        std::cerr << "failed to parse options" << std::endl;
+        return ret;
+    }
+
+    spla::Timer     timer_total;
+    spla::Timer     timer_gpu;
+    spla::Timer     timer_ref;
+    spla::MtxLoader loader;
+
+    timer_total.start();
+
+    if (!loader.load(args["mtxpath"].as<std::string>())) {
+        std::cerr << "failed to load graph";
+        return 1;
+    }
+
+    std::string    acc_info;
+    spla::Library* library = spla::Library::get();
+
+    library->set_platform(args["platform"].as<int>());
+    library->set_device(args["device"].as<int>());
+    library->set_queues_count(1);
+    library->get_accelerator_info(acc_info);
+    std::cout << "env: " << acc_info << std::endl;
+
+    const spla::uint N = loader.get_n_rows();
+    auto             S = spla::Matrix::make(N, N, spla::PAIR);
+
+    const auto& Ai = loader.get_Ai();
+    const auto& Aj = loader.get_Aj();
+    const auto& Aw = loader.get_Aw();
+
+    for (std::size_t k = 0; k < loader.get_n_values(); ++k) {
+        S->set_pair(Ai[k], Aj[k], spla::T_PAIR(Aw[k], Aj[k]));
+    }
+
+    auto T_gpu = spla::Matrix::make(N, N, spla::FLOAT);
+
+    auto desc = spla::Descriptor::make();
+
+    const int n_iters = args["niters"].as<int>();
+
+    double total_weight_gpu = 0.0;
+
+    if (args["run-gpu"].as<bool>()) {
+        library->set_force_no_acceleration(false);
+
+        for (int i = 0; i < n_iters; ++i) {
+            T_gpu->clear();
+            S = spla::Matrix::make(N, N, spla::PAIR);
+            for (std::size_t k = 0; k < loader.get_n_values(); ++k) {
+                S->set_pair(Ai[k], Aj[k], spla::T_PAIR(Aw[k], Aj[k]));
+            }
+            timer_gpu.lap_begin();
+            spla::mst(T_gpu, S, desc, nullptr);
+            timer_gpu.lap_end();
+        }
+
+        total_weight_gpu = 0;
+        for (spla::uint i = 0; i < N; ++i) {
+            for (spla::uint j = i + 1; j < N; ++j) {
+                float w;
+                T_gpu->get_float(i, j, w);
+                if (w != 0.0) {
+                    total_weight_gpu += w;
+                }
+            }
+        }
+
+        std::cout << "GPU MST total weight: " << total_weight_gpu << std::endl;
+    }
+
+    spla::Library::get()->finalize();
+
+    timer_total.stop();
+
+    std::cout << "\n=== Timing Results ===" << std::endl;
+    std::cout << "total(ms):" << timer_total.get_elapsed_ms() << std::endl;
+    std::cout << "gpu(ms): ";
+    timer_gpu.print();
+    std::cout << std::endl;
+
+    return 0;
+}

include/spla.hpp

@@ -39,6 +39,7 @@
 #include "spla/memview.hpp"
 #include "spla/object.hpp"
 #include "spla/op.hpp"
+#include "spla/pair.hpp"
 #include "spla/ref.hpp"
 #include "spla/scalar.hpp"
 #include "spla/schedule.hpp"