From e08f7d177bf59382536ef07074f70c0c8dc5de69 Mon Sep 17 00:00:00 2001
From: Alex Guteniev <gutenev@gmail.com>
Date: Mon, 12 Feb 2024 20:04:59 +0200
Subject: [PATCH 1/2] Add `find` / `count` benchmark

Ported from #2434 description, dropping unnecessary parts
---
 benchmarks/CMakeLists.txt         |  1 +
 benchmarks/src/find_and_count.cpp | 73 +++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+)
 create mode 100644 benchmarks/src/find_and_count.cpp

diff --git a/benchmarks/CMakeLists.txt b/benchmarks/CMakeLists.txt
index 1a5071ea583..4b586a786d1 100644
--- a/benchmarks/CMakeLists.txt
+++ b/benchmarks/CMakeLists.txt
@@ -109,6 +109,7 @@ function(add_benchmark name)
 endfunction()
 
 add_benchmark(bitset_to_string src/bitset_to_string.cpp)
+add_benchmark(find_and_count src/find_and_count.cpp)
 add_benchmark(locale_classic src/locale_classic.cpp)
 add_benchmark(minmax_element src/minmax_element.cpp)
 add_benchmark(path_lexically_normal src/path_lexically_normal.cpp)
diff --git a/benchmarks/src/find_and_count.cpp b/benchmarks/src/find_and_count.cpp
new file mode 100644
index 00000000000..1126f3f2b01
--- /dev/null
+++ b/benchmarks/src/find_and_count.cpp
@@ -0,0 +1,73 @@
+// Copyright (c) Microsoft Corporation.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <algorithm>
+#include <benchmark/benchmark.h>
+#include <cstddef>
+#include <cstdint>
+#include <ranges>
+#include <type_traits>
+
+enum class Op {
+    FindSized,
+    FindUnsized,
+    Count,
+};
+
+using namespace std;
+
+template <class T, size_t Size, size_t Pos, Op Operation>
+void bm(benchmark::State& state) {
+    T a[Size];
+
+    std::fill_n(a, Size, T{'0'});
+    if constexpr (Pos < Size) {
+        a[Pos] = T{'1'};
+    } else {
+        static_assert(Operation != Op::FindUnsized);
+    }
+
+    for (auto _ : state) {
+        if constexpr (Operation == Op::FindSized) {
+            benchmark::DoNotOptimize(ranges::find(a, a + Size, T{'1'}));
+        } else if constexpr (Operation == Op::FindUnsized) {
+            benchmark::DoNotOptimize(ranges::find(a, std::unreachable_sentinel, T{'1'}));
+        } else if constexpr (Operation == Op::Count) {
+            benchmark::DoNotOptimize(ranges::count(a, a + Size, T{'1'}));
+        }
+    }
+}
+
+BENCHMARK(bm<uint8_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<uint8_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<uint8_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<uint16_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<uint16_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<uint16_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<uint32_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<uint32_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<uint32_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<uint64_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<uint64_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<uint64_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<int8_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<int8_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<int8_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<int16_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<int16_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<int16_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<int32_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<int32_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<int32_t, 8021, 3056, Op::Count>);
+
+BENCHMARK(bm<int64_t, 8021, 3056, Op::FindSized>);
+BENCHMARK(bm<int64_t, 8021, 3056, Op::FindUnsized>);
+BENCHMARK(bm<int64_t, 8021, 3056, Op::Count>);
+
+BENCHMARK_MAIN();

From f10b441a71f77f74883355a9830fa8e6f2596e05 Mon Sep 17 00:00:00 2001
From: "Stephan T. Lavavej" <stl@nuwen.net>
Date: Mon, 12 Feb 2024 15:27:14 -0800
Subject: [PATCH 2/2] Code review nitpicks.

---
 benchmarks/src/find_and_count.cpp | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/benchmarks/src/find_and_count.cpp b/benchmarks/src/find_and_count.cpp
index 1126f3f2b01..0b7561d4a9a 100644
--- a/benchmarks/src/find_and_count.cpp
+++ b/benchmarks/src/find_and_count.cpp
@@ -6,7 +6,6 @@
 #include <cstddef>
 #include <cstdint>
 #include <ranges>
-#include <type_traits>
 
 enum class Op {
     FindSized,
@@ -20,7 +19,7 @@ template <class T, size_t Size, size_t Pos, Op Operation>
 void bm(benchmark::State& state) {
     T a[Size];
 
-    std::fill_n(a, Size, T{'0'});
+    fill_n(a, Size, T{'0'});
     if constexpr (Pos < Size) {
         a[Pos] = T{'1'};
     } else {
@@ -31,7 +30,7 @@ void bm(benchmark::State& state) {
         if constexpr (Operation == Op::FindSized) {
             benchmark::DoNotOptimize(ranges::find(a, a + Size, T{'1'}));
         } else if constexpr (Operation == Op::FindUnsized) {
-            benchmark::DoNotOptimize(ranges::find(a, std::unreachable_sentinel, T{'1'}));
+            benchmark::DoNotOptimize(ranges::find(a, unreachable_sentinel, T{'1'}));
         } else if constexpr (Operation == Op::Count) {
             benchmark::DoNotOptimize(ranges::count(a, a + Size, T{'1'}));
         }