[libcxx-commits] [libcxx] [libc++] Optimize {std, ranges}::for_each for iterating over __trees (PR #164405)

[Louis Dionne via libcxx-commits]

================
@@ -44,12 +46,98 @@ int main(int argc, char** argv) {
           ->Arg(50) // non power-of-two
           ->Arg(8192);
     };
-    bm.operator()<std::vector<int>>("std::for_each(vector<int>)", std_for_each);
-    bm.operator()<std::deque<int>>("std::for_each(deque<int>)", std_for_each);
-    bm.operator()<std::list<int>>("std::for_each(list<int>)", std_for_each);
-    bm.operator()<std::vector<int>>("rng::for_each(vector<int>)", std::ranges::for_each);
-    bm.operator()<std::deque<int>>("rng::for_each(deque<int>)", std::ranges::for_each);
-    bm.operator()<std::list<int>>("rng::for_each(list<int>)", std::ranges::for_each);
+    sequence_bm.operator()<std::vector<int>>("std::for_each(vector<int>)", std_for_each);
+    sequence_bm.operator()<std::deque<int>>("std::for_each(deque<int>)", std_for_each);
+    sequence_bm.operator()<std::list<int>>("std::for_each(list<int>)", std_for_each);
+    sequence_bm.operator()<std::vector<int>>("rng::for_each(vector<int>)", std::ranges::for_each);
+    sequence_bm.operator()<std::deque<int>>("rng::for_each(deque<int>)", std::ranges::for_each);
+    sequence_bm.operator()<std::list<int>>("rng::for_each(list<int>)", std::ranges::for_each);
+
+    auto associative_bm =
+        []<class Container, bool IsMapLike>(
+            std::type_identity<Container>, std::bool_constant<IsMapLike>, std::string name, auto for_each) {
----------------
ldionne wrote:

I don't think you actually need `auto for_each` to be a parameter to this function.

https://github.com/llvm/llvm-project/pull/164405