[libcxx-commits] [libcxx] [libc++] Allow running the test suite with optimizations (PR #68753)

[Louis Dionne via libcxx-commits]

https://github.com/ldionne created https://github.com/llvm/llvm-project/pull/68753

This patch adds a configuration of the libc++ test suite that enables optimizations when building the tests. It also adds a new CI configuration to exercise this on a regular basis. This is added in the context of [1], which requires building with optimizations in order to hit the bug.

[1]: https://github.com/llvm/llvm-project/issues/68552

>From 6d27185b34d30e06477d647f500428252510e5da Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Tue, 10 Oct 2023 16:35:11 -0700
Subject: [PATCH] [libc++] Allow running the test suite with optimizations

This patch adds a configuration of the libc++ test suite that enables
optimizations when building the tests. It also adds a new CI configuration
to exercise this on a regular basis. This is added in the context of [1],
which requires building with optimizations in order to hit the bug.

[1]: https://github.com/llvm/llvm-project/issues/68552
---
 libcxx/cmake/caches/Generic-optimized.cmake |  4 +++
 libcxx/utils/ci/buildkite-pipeline.yml      | 18 +++++++++++++
 libcxx/utils/ci/run-buildbot                |  5 ++++
 libcxx/utils/libcxx/test/params.py          | 28 ++++++++++++++++++++-
 4 files changed, 54 insertions(+), 1 deletion(-)
 create mode 100644 libcxx/cmake/caches/Generic-optimized.cmake

diff --git a/libcxx/cmake/caches/Generic-optimized.cmake b/libcxx/cmake/caches/Generic-optimized.cmake
new file mode 100644
index 000000000000000..577a5de9f34c539
--- /dev/null
+++ b/libcxx/cmake/caches/Generic-optimized.cmake
@@ -0,0 +1,4 @@
+set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
+set(LIBCXX_TEST_PARAMS "optimization=speed" CACHE STRING "")
+set(LIBCXXABI_TEST_PARAMS "${LIBCXX_TEST_PARAMS}" CACHE STRING "")
+set(LIBUNWIND_TEST_PARAMS "${LIBCXX_TEST_PARAMS}" CACHE STRING "")
diff --git a/libcxx/utils/ci/buildkite-pipeline.yml b/libcxx/utils/ci/buildkite-pipeline.yml
index ebfb35eee91e1ed..1b52d994081c46f 100644
--- a/libcxx/utils/ci/buildkite-pipeline.yml
+++ b/libcxx/utils/ci/buildkite-pipeline.yml
@@ -743,6 +743,24 @@ steps:
           limit: 2
     timeout_in_minutes: 120
 
+  - label: "Optimized build and test suite"
+    command: "libcxx/utils/ci/run-buildbot generic-optimized"
+    artifact_paths:
+      - "**/test-results.xml"
+      - "**/*.abilist"
+    env:
+        CC: "clang-${LLVM_HEAD_VERSION}"
+        CXX: "clang++-${LLVM_HEAD_VERSION}"
+        ENABLE_CLANG_TIDY: "On"
+    agents:
+      queue: "libcxx-builders"
+      os: "linux"
+    retry:
+      automatic:
+        - exit_status: -1  # Agent was lost
+          limit: 2
+    timeout_in_minutes: 120
+
   # Other non-testing CI jobs
   - label: "Benchmarks"
     command: "libcxx/utils/ci/run-buildbot benchmarks"
diff --git a/libcxx/utils/ci/run-buildbot b/libcxx/utils/ci/run-buildbot
index a71318123db3b12..18243b44a3d745c 100755
--- a/libcxx/utils/ci/run-buildbot
+++ b/libcxx/utils/ci/run-buildbot
@@ -479,6 +479,11 @@ generic-abi-unstable)
     generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-abi-unstable.cmake"
     check-runtimes
 ;;
+generic-optimized)
+    clean
+    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-optimized.cmake"
+    check-runtimes
+;;
 apple-system)
     clean
 
diff --git a/libcxx/utils/libcxx/test/params.py b/libcxx/utils/libcxx/test/params.py
index 456794b9b1cce95..9452f179aea3fec 100644
--- a/libcxx/utils/libcxx/test/params.py
+++ b/libcxx/utils/libcxx/test/params.py
@@ -11,7 +11,7 @@
 from pathlib import Path
 
 from libcxx.test.dsl import *
-from libcxx.test.features import _isMSVC
+from libcxx.test.features import _isClang, _isAppleClang, _isGCC, _isMSVC
 
 
 _warningFlags = [
@@ -90,6 +90,21 @@ def getStdFlag(cfg, std):
         return "-std=" + fallbacks[std]
     return None
 
+def getSpeedOptimizationFlag(cfg):
+    if _isClang(cfg) or _isAppleClang(cfg) or _isGCC(cfg):
+        return "-O3"
+    elif _isMSVC(cfg):
+        return "/O2"
+    else:
+        raise RuntimeError("Can't figure out what compiler is used in the configuration")
+
+def getSizeOptimizationFlag(cfg):
+    if _isClang(cfg) or _isAppleClang(cfg) or _isGCC(cfg):
+        return "-Os"
+    elif _isMSVC(cfg):
+        return "/O1"
+    else:
+        raise RuntimeError("Can't figure out what compiler is used in the configuration")
 
 # fmt: off
 DEFAULT_PARAMETERS = [
@@ -121,6 +136,17 @@ def getStdFlag(cfg, std):
             AddCompileFlag(lambda cfg: getStdFlag(cfg, std)),
         ],
     ),
+    Parameter(
+        name="optimization",
+        choices=["none", "speed", "size"],
+        type=str,
+        help="The version of the standard to compile the test suite with.",
+        default="none",
+        actions=lambda opt: filter(None, [
+            AddCompileFlag(lambda cfg: getSpeedOptimizationFlag(cfg)) if opt == "speed" else None,
+            AddCompileFlag(lambda cfg: getSizeOptimizationFlag(cfg)) if opt == "size" else None,
+        ]),
+    ),
     Parameter(
         name="enable_modules",
         choices=["none", "clang", "clang-lsv"],