Rename cxx-benchmark-unittests target and convert to LIT.
This patch renames the cxx-benchmark-unittests to check-cxx-benchmarks
and converts the target to use LIT in order to make the tests run faster
and provide better output.
In particular this runs each benchmark in a suite one by one, allowing
more parallelism while ensuring output isn't garbage with multiple threads.
Additionally, it adds the CMake flag '-DLIBCXX_BENCHMARK_TEST_ARGS=<list>'
to specify what options are passed when running the benchmarks.
llvm-svn: 346888
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 336a1a681189bf2b50b7bd0f8229656c58ac1b37
diff --git a/docs/BuildingLibcxx.rst b/docs/BuildingLibcxx.rst
index 66cfb7b..12acd0b 100644
--- a/docs/BuildingLibcxx.rst
+++ b/docs/BuildingLibcxx.rst
@@ -316,6 +316,15 @@
Build the libc++ benchmark tests and the Google Benchmark library needed
to support them.
+.. option:: LIBCXX_BENCHMARK_TEST_ARGS:STRING
+
+ **Default**: ``--benchmark_min_time=0.01``
+
+ A semicolon list of arguments to pass when running the libc++ benchmarks using the
+ ``check-cxx-benchmarks`` rule. By default we run the benchmarks for a very short amount of time,
+ since the primary use of ``check-cxx-benchmarks`` is to get test and sanitizer coverage, not to
+ get accurate measurements.
+
.. option:: LIBCXX_BENCHMARK_NATIVE_STDLIB:STRING
**Default**:: ``""``