llvm_tools: add package stabilization script

This allows a dev to make all changes in their LLVM ebuilds stable with
a single command. Critically, if used with `--llvm-next`, a user can run
`cros-tree bootstrap-sdk` in the tree this was run in, and they'll get
something very close to an SDK run with llvm-next, but locally.

No tests are included, since this has near zero conditional logic. Vast
majority of that is elsewhere.

BUG=b:333737743
TEST=Ran the script with --llvm-next, with an updated llvm-next.
TEST=New ebuilds were created, as expected.

Change-Id: Iad7bdcd4c51828e185fea698cd43922be47dd75f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5444011
Commit-Queue: George Burgess <gbiv@chromium.org>
Reviewed-by: Ryan Beltran <ryanbeltran@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>

1 files changed, 141 insertions, 0 deletions

diff --git a/llvm_tools/stabilize_all_llvm_packages.py b/llvm_tools/stabilize_all_llvm_packages.py
new file mode 100755
index 00000000..40ca29f5
--- /dev/null
+++ b/llvm_tools/stabilize_all_llvm_packages.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+# Copyright 2024 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Marks all LLVM packages as stable.
+
+This essentially performs the job of annealing: take whatever's in the 9999
+ebuilds, and put it in non-9999 ebuilds. The result is committed to
+chromiumos-overlay, unless there are no changes to make. If the stabilization
+does nothing, no new ebuilds will be created, and nothing will be committed.
+
+The results of this script should _not_ be uploaded. Annealing should be
+responsible for actually stabilizing our ebuilds upstream.
+
+Run this from inside of the chroot.
+"""
+
+import argparse
+import contextlib
+import logging
+from pathlib import Path
+import subprocess
+import sys
+from typing import List
+
+import chroot
+import get_upstream_patch
+import manifest_utils
+import patch_utils
+
+
+CROS_SOURCE_ROOT = Path("/mnt/host/source")
+
+
+@contextlib.contextmanager
+def llvm_checked_out_to(checkout_sha: str):
+    """Checks out LLVM to `checkout_sha`, if necessary.
+
+    Restores LLVM to the prior SHA when exited.
+    """
+    llvm_dir = CROS_SOURCE_ROOT / manifest_utils.LLVM_PROJECT_PATH
+    original_sha = subprocess.run(
+        ["git", "rev-parse", "HEAD"],
+        check=True,
+        cwd=llvm_dir,
+        stdout=subprocess.PIPE,
+        encoding="utf-8",
+    ).stdout.strip()
+    if checkout_sha == original_sha:
+        logging.info(
+            "LLVM is already checked out to %s; not checking out", checkout_sha
+        )
+        yield
+        return
+
+    return_code = subprocess.run(
+        ["git", "status", "--porcelain"],
+        check=False,
+        cwd=llvm_dir,
+    ).returncode
+    if return_code:
+        raise ValueError(
+            f"LLVM checkout at {llvm_dir} is unclean; refusing to modify"
+        )
+
+    logging.info("Checking %s out to SHA %s...", llvm_dir, checkout_sha)
+
+    subprocess.run(
+        ["git", "checkout", checkout_sha],
+        check=True,
+        cwd=llvm_dir,
+    )
+    try:
+        yield
+    finally:
+        logging.info("Restoring %s to original checkout...", llvm_dir)
+        return_code = subprocess.run(
+            ["git", "checkout", original_sha],
+            check=False,
+            cwd=llvm_dir,
+        ).returncode
+        if return_code:
+            logging.error(
+                "Failed checking llvm-project back out to %s :(",
+                original_sha,
+            )
+
+
+def resolve_llvm_sha(llvm_next: bool) -> str:
+    sys_devel_llvm = (
+        CROS_SOURCE_ROOT / "src/third_party/chromiumos-overlay/sys-devel/llvm"
+    )
+    sha = "llvm-next" if llvm_next else "llvm"
+    return get_upstream_patch.resolve_symbolic_sha(sha, str(sys_devel_llvm))
+
+
+def main(argv: List[str]) -> None:
+    chroot.VerifyInsideChroot()
+
+    logging.basicConfig(
+        format=">> %(asctime)s: %(levelname)s: %(filename)s:%(lineno)d: "
+        "%(message)s",
+        level=logging.INFO,
+    )
+
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+    )
+    parser.add_argument(
+        "--llvm-next",
+        action="store_true",
+        help="""
+        If passed, the ebuilds will be stabilized using the current llvm-next
+        hash.
+        """,
+    )
+    opts = parser.parse_args(argv)
+    desired_sha = resolve_llvm_sha(opts.llvm_next)
+
+    with llvm_checked_out_to(desired_sha):
+        packages_to_stabilize = patch_utils.CHROMEOS_PATCHES_JSON_PACKAGES
+        logging.info("Stabilizing %s...", ", ".join(packages_to_stabilize))
+
+        cros_overlay = CROS_SOURCE_ROOT / "src/third_party/chromiumos-overlay"
+        return_code = subprocess.run(
+            [
+                "cros_mark_as_stable",
+                f"--overlays={cros_overlay}",
+                "--packages=" + ":".join(packages_to_stabilize),
+                "commit",
+            ],
+            check=False,
+            stdin=subprocess.DEVNULL,
+        ).returncode
+        sys.exit(return_code)
+
+
+if __name__ == "__main__":
+    main(sys.argv[1:])