[libc++][NFC] Add missing license headers

Also standardize the license comment in several files where it was
different from what we normally do.

NOKEYCHECK=True
GitOrigin-RevId: 6a54dfbfe534276d644d7f9c027f0deeb748dd53

Author: ldionne

test/benchmarks/GenerateInput.h

@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #ifndef BENCHMARK_GENERATE_INPUT_H
 #define BENCHMARK_GENERATE_INPUT_H
 

test/benchmarks/algorithms.partition_point.bench.cpp

@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include <algorithm>
 #include <array>
 #include <cassert>

test/benchmarks/algorithms/min.bench.cpp

@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include <algorithm>
 #include <cassert>
 

test/benchmarks/algorithms/minmax.bench.cpp

@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include <algorithm>
 #include <cassert>
 

test/benchmarks/atomic_wait.bench.cpp

@@ -1,4 +1,5 @@
 //===----------------------------------------------------------------------===//
+//
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

test/benchmarks/atomic_wait_vs_mutex_lock.bench.cpp

@@ -1,4 +1,5 @@
 //===----------------------------------------------------------------------===//
+//
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

test/benchmarks/filesystem.bench.cpp

@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include <filesystem>
 
 #include "GenerateInput.h"

test/benchmarks/format.bench.cpp

@@ -1,4 +1,5 @@
 //===----------------------------------------------------------------------===//
+//
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

test/benchmarks/format_to.bench.cpp

@@ -1,4 +1,5 @@
 //===----------------------------------------------------------------------===//
+//
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

test/benchmarks/format_to_n.bench.cpp

@@ -1,4 +1,5 @@
 //===----------------------------------------------------------------------===//
+//
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception