new file mode 100755
@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+#
+# check-units.py: check the number of compilation units and identify
+# those that are rebuilt multiple times
+#
+# Copyright (C) 2025 Linaro Ltd.
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+from os import access, R_OK, path
+from sys import argv, exit
+import json
+from collections import Counter
+
+
+def extract_build_units(cc_path):
+ """
+ Extract the build units and their counds from compile_commands.json file.
+
+ Returns:
+ Hash table of ["unit"] = count
+ """
+
+ j = json.load(open(cc_path, 'r'))
+ files = [f['file'] for f in j]
+ build_units = Counter(files)
+
+ return build_units
+
+
+def analyse_units(build_units):
+ """
+ Analyse the build units and report stats and the top 10 rebuilds
+ """
+
+ print(f"Total source files: {len(build_units.keys())}")
+ print(f"Total build units: {sum(units.values())}")
+
+ # Create a sorted list by number of rebuilds
+ sorted_build_units = sorted(build_units.items(),
+ key=lambda item: item[1],
+ reverse=True)
+
+ print("Most rebuilt units:")
+ for unit, count in sorted_build_units[:20]:
+ print(f" {unit} built {count} times")
+
+ print("Least rebuilt units:")
+ for unit, count in sorted_build_units[-10:]:
+ print(f" {unit} built {count} times")
+
+
+if __name__ == "__main__":
+ if len(argv) != 2:
+ script_name = path.basename(argv[0])
+ print(f"Usage: {script_name} <path_to_compile_commands.json>")
+ exit(1)
+
+ cc_path = argv[1]
+ if path.isfile(cc_path) and access(cc_path, R_OK):
+ units = extract_build_units(cc_path)
+ analyse_units(units)
+ exit(0)
+ else:
+ print(f"{cc_path} doesn't exist or isn't readable")
+ exit(1)
@@ -70,3 +70,25 @@ check-rust-tools-nightly:
expire_in: 2 days
paths:
- rust/target/doc
+
+check-build-units:
+ extends: .base_job_template
+ stage: build
+ image: $CI_REGISTRY_IMAGE/qemu/debian:$QEMU_CI_CONTAINER_TAG
+ needs:
+ job: amd64-debian-container
+ before_script:
+ - source scripts/ci/gitlab-ci-section
+ - section_start setup "Install Tools"
+ - apt install --assume-yes --no-install-recommends jq
+ - section_end setup
+ script:
+ - mkdir build
+ - cd build
+ - section_start configure "Running configure"
+ - ../configure
+ - cd ..
+ - section_end configure
+ - section_start analyse "Analyse"
+ - .gitlab-ci.d/check-units.py build/compile_commands.json
+ - section_end analyse
We want to reduce the total number of build units in the system to get on our way to a single binary. It will help to have some numbers so lets add a job to gitlab to track our progress. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Cc: Pierrick Bouvier <pierrick.bouvier@linaro.org> Cc: Philippe Mathieu-Daudé <philmd@linaro.org> Cc: Richard Henderson <richard.henderson@linaro.org> --- v2 - do all json in python --- .gitlab-ci.d/check-units.py | 66 ++++++++++++++++++++++++++++++++++ .gitlab-ci.d/static_checks.yml | 22 ++++++++++++ 2 files changed, 88 insertions(+) create mode 100755 .gitlab-ci.d/check-units.py