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Author: ldionne

libcxx/utils/ci/run-buildbot

@@ -546,12 +546,15 @@ benchmark-comparison)
     clean
     LIT_ARGS="-sv -j1 --param optimization=speed libcxx/test/benchmarks/hash.bench.cpp libcxx/test/benchmarks/join_view.bench.cpp"
 
-    if [[ "${BASELINE_COMMIT}" == "" ]]; then
-        BASELINE_COMMIT=$(git merge-base main HEAD)
+    if [[ "${GITHUB_BASE_REF}" != "" ]]; then # triggered from a PR
+        baseline_commit=$(git merge-base ${GITHUB_BASE_REF} ${GITHUB_SHA})
+    else
+        baseline_commit=$(git merge-base main HEAD)
     fi
-    step "Building and running the baseline at ${BASELINE_COMMIT}"
+
+    step "Building and running the baseline at ${baseline_commit}"
     rm -rf "${BUILD_DIR}-baseline"
-    ./libcxx/utils/test-at-commit --commit ${BASELINE_COMMIT} -B "${BUILD_DIR}-baseline" -- ${LIT_ARGS}
+    ./libcxx/utils/test-at-commit --commit ${baseline_commit} -B "${BUILD_DIR}-baseline" -- ${LIT_ARGS}
 
     # Build and run the candidate
     step "Building and running the candidate"