Add different copy methods

benchmarks/memory/BUILD.bazel

@@ -5,6 +5,7 @@ cc_binary(
     srcs = ["memcpy_benchmark.cpp"],
     deps = [
         "//lib/memory:memcpy",
+        "//lib/memory/copy:copy",
         "@google_benchmark//:benchmark_main",
     ],
 )

benchmarks/memory/memcpy_benchmark.cpp

@@ -1,3 +1,4 @@
+#include "lib/memory/copy/copy.h"
 #include "lib/memory/memcpy.h"
 
 #include <cstddef>
@@ -18,14 +19,14 @@ std::vector<std::byte> MakeInput(std::size_t size) {
   return input;
 }
 
-void BM_Memcpy(benchmark::State& state) {
+template <auto CopyFn>
+void BM_Copy(benchmark::State& state) {
   const auto size = static_cast<std::size_t>(state.range(0));
   const std::vector<std::byte> source = MakeInput(size);
   std::vector<std::byte> destination(size);
 
   for (auto _ : state) {
-    memcopy_bench::memory::CopyWithMemcpy(
-        destination.data(), source.data(), size);
+    CopyFn(destination.data(), source.data(), size);
     benchmark::DoNotOptimize(destination.data());
     benchmark::ClobberMemory();
   }
@@ -34,8 +35,42 @@ void BM_Memcpy(benchmark::State& state) {
                           static_cast<std::int64_t>(size));
 }
 
-BENCHMARK(BM_Memcpy)->RangeMultiplier(4)->Range(64, 64 << 20);
+inline void* CopyNaiveWrapper(void* d, const void* s, std::size_t n) {
+  return memory_bench::copy_naive(d, s, n);
+}
+
+} // namespace
+
+template <auto Fn>
+void RegisterBMCopy(const char *name)
+{
+  benchmark::RegisterBenchmark(name, BM_Copy<Fn>)
+    ->RangeMultiplier(4)
+    ->Range(64, 64 << 20);
+}
+
+static const bool Registered = []
+{
+  RegisterBMCopy<memcopy_bench::memory::CopyWithMemcpy>("BM_Memcpy");
+  RegisterBMCopy<CopyNaiveWrapper>("BM_CopyNaive");
+  RegisterBMCopy<memory_bench::copy_duff>("BM_CopyDuff");
+  RegisterBMCopy<memory_bench::copy_words64>("BM_CopyWords64");
+  RegisterBMCopy<memory_bench::copy_words64_unrolled4>("BM_CopyWords64Unrolled4");
+  RegisterBMCopy<memory_bench::copy_small_overlapping>("BM_CopySmallOverlapping");
+  return true;
+}();
 
-}  // namespace
+#if defined(__x86_64__) || defined(_M_X64)
+static const bool x86Registered = []
+{
+  RegisterBMCopy<memory_bench::copy_rep_movsb>("BM_CopyRepMovsb");
+  RegisterBMCopy<memory_bench::copy_rep_movsq>("BM_CopyRepMovsq");
+  RegisterBMCopy<memory_bench::copy_sse2>("BM_CopySSE2");
+  RegisterBMCopy<memory_bench::copy_avx2>("BM_CopyAVX2");
+  RegisterBMCopy<memory_bench::copy_avx2_stream>("BM_CopyAVX2Stream");
+  RegisterBMCopy<memory_bench::copy_avx2_prefetch>("BM_CopyAVX2Prefetch");
+  return true;
+}();
+#endif
 
 BENCHMARK_MAIN();

justfile

@@ -0,0 +1,39 @@
+# Set default recipe to show available commands
+default:
+    @just --list
+
+# Build all targets in the workspace
+build:
+    bazel build //...
+
+# Run all unit tests with error logs on failure
+test:
+    bazel test //... --test_output=errors
+
+# Run AddressSanitizer and UndefinedBehaviorSanitizer checks
+sanitizers:
+    bazel test --config=asan //... --test_output=errors
+    bazel test --config=ubsan //... --test_output=errors
+
+# Run C++ linter (clang-tidy)
+lint:
+    sh tools/run-clang-tidy.sh
+
+# Run complete local verification (format, lint, tests, and sanitizers)
+check: lint test sanitizers
+
+# Run benchmarks (optional filter argument: `just bench BM_Memcpy`)
+bench filter="":
+    bazel run //benchmarks/memory:memcpy_benchmark -- {{ if filter != "" { "--benchmark_filter=" + filter } else { "" } }}
+
+# Refresh compile_commands.json for clangd and IDE completion
+compile-commands:
+    bazel run @hedron_compile_commands//:refresh_all
+
+# Remove local build outputs and symlinks
+clean:
+    bazel clean
+
+# Wipe the entire local Bazel cache and reset external downloads
+clean-all:
+    bazel clean --expunge

lib/memory/copy/BUILD.bazel

@@ -0,0 +1,17 @@
+load("@rules_cc//cc:cc_library.bzl", "cc_library")
+load("@rules_cc//cc:cc_test.bzl", "cc_test")
+
+cc_library(
+    name = "copy",
+    hdrs = ["copy.h"],
+    visibility = ["//visibility:public"],
+)
+
+cc_test(
+    name = "copy_test",
+    srcs = ["copy_test.cpp"],
+    deps = [
+        ":copy",
+        "@googletest//:gtest_main",
+    ],
+)