[CI] Explicitly compute needed runtime targets

This patch adjusts the compute_projects script to explicitly determine
what runtimes should be built and what runtimes should be tested. This
is mainly to support enabling runtimes for LLDB testing but not test
them unless we are building clang.

Reviewers: Endilll, tstellar, DavidSpickett, lnihlen

Reviewed By: DavidSpickett

Pull Request: #142695

Author: boomanaiden154

.ci/compute_projects.py

@@ -57,6 +57,13 @@
     ".ci": {"llvm", "clang", "lld", "lldb"},
 }
 
+# This mapping describes runtimes that should be enabled for a specific project,
+# but not necessarily run for testing. The only case of this currently is lldb
+# which needs some runtimes enabled for tests.
+DEPENDENT_RUNTIMES_TO_BUILD = {"lldb": {"libcxx", "libcxxabi", "libunwind"}}
+
+# This mapping describes runtimes that should be tested when the key project is
+# touched.
 DEPENDENT_RUNTIMES_TO_TEST = {"clang": {"libcxx", "libcxxabi", "libunwind"}}
 
 EXCLUDE_LINUX = {
@@ -180,16 +187,20 @@ def _compute_project_check_targets(projects_to_test: Set[str]) -> Set[str]:
 def _compute_runtimes_to_test(projects_to_test: Set[str]) -> Set[str]:
     runtimes_to_test = set()
     for project_to_test in projects_to_test:
-        if project_to_test not in DEPENDENT_RUNTIMES_TO_TEST:
-            continue
-        runtimes_to_test.update(DEPENDENT_RUNTIMES_TO_TEST[project_to_test])
+        if project_to_test in DEPENDENT_RUNTIMES_TO_TEST:
+            runtimes_to_test.update(DEPENDENT_RUNTIMES_TO_TEST[project_to_test])
+        if project_to_test in DEPENDENT_RUNTIMES_TO_BUILD:
+            runtimes_to_test.update(DEPENDENT_RUNTIMES_TO_BUILD[project_to_test])
     return runtimes_to_test
 
 
-def _compute_runtime_check_targets(runtimes_to_test: Set[str]) -> Set[str]:
+def _compute_runtime_check_targets(projects_to_test: Set[str]) -> Set[str]:
     check_targets = set()
-    for runtime_to_test in runtimes_to_test:
-        check_targets.add(PROJECT_CHECK_TARGETS[runtime_to_test])
+    for project_to_test in projects_to_test:
+        if project_to_test not in DEPENDENT_RUNTIMES_TO_TEST:
+            continue
+        for runtime_to_test in DEPENDENT_RUNTIMES_TO_TEST[project_to_test]:
+            check_targets.add(PROJECT_CHECK_TARGETS[runtime_to_test])
     return check_targets
 
 
@@ -216,16 +227,16 @@ def get_env_variables(modified_files: list[str], platform: str) -> Set[str]:
     projects_to_test = _compute_projects_to_test(modified_projects, platform)
     projects_to_build = _compute_projects_to_build(projects_to_test)
     projects_check_targets = _compute_project_check_targets(projects_to_test)
-    runtimes_to_test = _compute_runtimes_to_test(projects_to_test)
-    runtimes_check_targets = _compute_runtime_check_targets(runtimes_to_test)
+    runtimes_to_build = _compute_runtimes_to_test(projects_to_test)
+    runtimes_check_targets = _compute_runtime_check_targets(projects_to_test)
     # We use a semicolon to separate the projects/runtimes as they get passed
     # to the CMake invocation and thus we need to use the CMake list separator
     # (;). We use spaces to separate the check targets as they end up getting
     # passed to ninja.
     return {
         "projects_to_build": ";".join(sorted(projects_to_build)),
         "project_check_targets": " ".join(sorted(projects_check_targets)),
-        "runtimes_to_build": ";".join(sorted(runtimes_to_test)),
+        "runtimes_to_build": ";".join(sorted(runtimes_to_build)),
         "runtimes_check_targets": " ".join(sorted(runtimes_check_targets)),
     }
 

.ci/compute_projects_test.py

@@ -205,6 +205,17 @@ def test_ci(self):
             "check-cxx check-cxxabi check-unwind",
         )
 
+    def test_lldb(self):
+        env_variables = compute_projects.get_env_variables(
+            ["lldb/CMakeLists.txt"], "Linux"
+        )
+        self.assertEqual(env_variables["projects_to_build"], "clang;lldb;llvm")
+        self.assertEqual(env_variables["project_check_targets"], "check-lldb")
+        self.assertEqual(
+            env_variables["runtimes_to_build"], "libcxx;libcxxabi;libunwind"
+        )
+        self.assertEqual(env_variables["runtimes_check_targets"], "")
+
 
 if __name__ == "__main__":
     unittest.main()

.ci/monolithic-linux.sh

@@ -55,6 +55,8 @@ trap at-exit EXIT
 
 projects="${1}"
 targets="${2}"
+runtimes="${3}"
+runtime_targets="${4}"
 
 lit_args="-v --xunit-xml-output ${BUILD_DIR}/test-results.xml --use-unique-output-file-name --timeout=1200 --time-tests"
 
@@ -70,7 +72,7 @@ export LLVM_SYMBOLIZER_PATH=`which llvm-symbolizer`
 # It will not be built unless it is used.
 cmake -S "${MONOREPO_ROOT}"/llvm -B "${BUILD_DIR}" \
       -D LLVM_ENABLE_PROJECTS="${projects}" \
-      -D LLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
+      -D LLVM_ENABLE_RUNTIMES="${runtimes}" \
       -G Ninja \
       -D CMAKE_PREFIX_PATH="${HOME}/.local" \
       -D CMAKE_BUILD_TYPE=Release \
@@ -91,17 +93,9 @@ echo "--- ninja"
 # Targets are not escaped as they are passed as separate arguments.
 ninja -C "${BUILD_DIR}" -k 0 ${targets}
 
-runtimes="${3}"
-runtime_targets="${4}"
-
 # Compiling runtimes with just-built Clang and running their tests
 # as an additional testing for Clang.
-if [[ "${runtimes}" != "" ]]; then
-  if [[ "${runtime_targets}" == "" ]]; then
-    echo "Runtimes to build are specified, but targets are not."
-    exit 1
-  fi
-
+if [[ "${runtimes_targets}" != "" ]]; then
   echo "--- cmake runtimes C++26"
 
   cmake \