[gcc/devel/omp/gcc-16] git_update_version.py: Support vendor-branch version bumps

https://gcc.gnu.org/g:75dc88863cfe75fe3e8d274a3408962f1b0c9c3b

commit 75dc88863cfe75fe3e8d274a3408962f1b0c9c3b
Author: Tobias Burnus <[email protected]>
Date:   Thu Apr 2 19:30:45 2026 +0000

    git_update_version.py: Support vendor-branch version bumps
    
    This patch incorporates commits dbd927be10e and subsequent bug fix
    cc7f48e65b9 from the OG15 branch.
    
    contrib/ChangeLog:
    
            * gcc-changelog/git_repository.py (parse_git_revisions): Optional
            exclude_branch_name argument.  Skip over merge commits for merges
            from exclude branch.
            * gcc-changelog/git_update_version.py: Add --suffix, --exclude-branch
            and --last-commit to handle vendor branches.  Handle merges.

Diff:
---
 contrib/gcc-changelog/git_repository.py     | 12 ++++-
 contrib/gcc-changelog/git_update_version.py | 70 +++++++++++++++++++++--------
 2 files changed, 63 insertions(+), 19 deletions(-)

diff --git a/contrib/gcc-changelog/git_repository.py b/contrib/gcc-changelog/git_repository.py
index 8703b45f8967..9fc036395b65 100755
--- a/contrib/gcc-changelog/git_repository.py
+++ b/contrib/gcc-changelog/git_repository.py
@@ -31,7 +31,8 @@ except ImportError:
 from git_commit import GitCommit, GitInfo, decode_path
 
 
-def parse_git_revisions(repo_path, revisions, ref_name=None):
+def parse_git_revisions(repo_path, revisions, ref_name=None,
+                        exclude_branch_name=None):
     repo = Repo(repo_path)
 
     def commit_to_info(commit):
@@ -67,6 +68,8 @@ def parse_git_revisions(repo_path, revisions, ref_name=None):
         except ValueError:
             return None
 
+    exclude_branch = (repo.commit(exclude_branch_name)
+                      if exclude_branch_name is not None else None)
     parsed_commits = []
     if '..' in revisions:
         commits = list(repo.iter_commits(revisions))
@@ -74,6 +77,13 @@ def parse_git_revisions(repo_path, revisions, ref_name=None):
         commits = [repo.commit(revisions)]
 
     for commit in commits:
+        if exclude_branch is not None:
+            if repo.is_ancestor(commit, exclude_branch):
+                continue
+            # Exlude merge commit
+            if (len(commit.parents) == 2
+                and repo.is_ancestor(commit.parents[1], exclude_branch)):
+                continue
         git_commit = GitCommit(commit_to_info(commit.hexsha),
                                commit_to_info_hook=commit_to_info,
                                ref_name=ref_name)
diff --git a/contrib/gcc-changelog/git_update_version.py b/contrib/gcc-changelog/git_update_version.py
index f4c024220113..da0e0421a381 100755
--- a/contrib/gcc-changelog/git_update_version.py
+++ b/contrib/gcc-changelog/git_update_version.py
@@ -23,6 +23,8 @@ import datetime
 import logging
 import os
 import re
+import shutil
+import sys
 
 from git import Repo
 
@@ -69,14 +71,14 @@ def read_timestamp(path):
         return f.read()
 
 
-def prepend_to_changelog_files(repo, folder, git_commit, add_to_git):
+def prepend_to_changelog_files(repo, folder, git_commit, add_to_git, suffix):
     if not git_commit.success:
         logging.info(f"While processing {git_commit.info.hexsha}:")
         for error in git_commit.errors:
             logging.info(error)
         raise AssertionError()
     for entry, output in git_commit.to_changelog_entries(use_commit_ts=True):
-        full_path = os.path.join(folder, entry, 'ChangeLog')
+        full_path = os.path.join(folder, entry, 'ChangeLog' + suffix)
         logging.info('writing to %s' % full_path)
         if os.path.exists(full_path):
             with open(full_path) as f:
@@ -96,7 +98,10 @@ active_refs = ['master',
                'releases/gcc-13', 'releases/gcc-14', 'releases/gcc-15']
 
 parser = argparse.ArgumentParser(description='Update DATESTAMP and generate '
-                                 'ChangeLog entries')
+                                 'ChangeLog entries',
+                                 epilog='For vendor branches, only; e.g: -s .suffix '
+                                 '-x releases/gcc-15 -l '
+                                 '`git log -1 --pretty=format:%H --grep "Vendor Bump"`')
 parser.add_argument('-g', '--git-path', default='.',
                     help='Path to git repository')
 parser.add_argument('-p', '--push', action='store_true',
@@ -109,26 +114,43 @@ parser.add_argument('-c', '--current', action='store_true',
                     help='Modify current branch (--push argument is ignored)')
 parser.add_argument('-i', '--ignore', action='append',
                     help='list of commits to ignore')
+# Useful only for vendor branches
+parser.add_argument('-s', '--suffix', default="",
+                    help='suffix for the ChangeLog and DATESTAMP files')
+parser.add_argument('-l', '--last-commit',
+                    help='hash of the last DATESTAMP commit')
+parser.add_argument('-x', '--exclude-branch',
+                    help='commits to be ignored if in this branch')
 args = parser.parse_args()
 
 repo = Repo(args.git_path)
 origin = repo.remotes['origin']
 
 
-def update_current_branch(ref_name=None):
+def update_current_branch(ref_name=None, suffix="", last_commit_ref=None,
+                          exclude_branch=None):
     commit = repo.head.commit
     commit_count = 1
-    while commit:
-        if (commit.author.email == '[email protected]'
-                and commit.message.strip() == 'Daily bump.'):
-            break
-        # We support merge commits but only with 2 parensts
-        assert len(commit.parents) <= 2
-        commit = commit.parents[-1]
-        commit_count += 1
-
-    logging.info('%d revisions since last Daily bump' % commit_count)
+    if last_commit_ref is not None:
+        commit = repo.commit(last_commit_ref)
+    else:
+        while commit:
+            if (commit.author.email == '[email protected]'
+                  and commit.message.strip() == 'Daily bump.'):
+                break
+            # We support merge commits but only with 2 parensts
+            assert len(commit.parents) <= 2
+            commit = commit.parents[-1]
+            commit_count += 1
+        logging.info('%d revisions since last Daily bump' % commit_count)
+
     datestamp_path = os.path.join(args.git_path, 'gcc/DATESTAMP')
+    if suffix != "":
+        if not os.path.exists(datestamp_path + suffix):
+            logging.info('Create DATESTAMP%s by copying DATESTAMP' % suffix)
+            shutil.copyfile(datestamp_path, datestamp_path + suffix)
+        datestamp_path += suffix
+
     if (read_timestamp(datestamp_path) != current_timestamp
             or args.dry_mode or args.current):
         head = repo.head.commit
@@ -138,11 +160,14 @@ def update_current_branch(ref_name=None):
         if len(head.parents) == 2:
             head = head.parents[1]
         commits = parse_git_revisions(args.git_path, '%s..%s'
-                                      % (commit.hexsha, head.hexsha), ref_name)
+                                      % (commit.hexsha, head.hexsha), ref_name,
+                                      exclude_branch)
         commits = [c for c in commits if c.info.hexsha not in ignored_commits]
+        if last_commit_ref is not None:
+            logging.info('%d revisions since last Daily bump' % len(commits))
         for git_commit in reversed(commits):
             prepend_to_changelog_files(repo, args.git_path, git_commit,
-                                       not args.dry_mode)
+                                       not args.dry_mode, args.suffix)
         if args.dry_mode:
             diff = repo.git.diff('HEAD')
             patch = os.path.join(args.dry_mode,
@@ -175,8 +200,17 @@ if args.ignore is not None:
 
 if args.current:
     logging.info('=== Working on the current branch ===')
-    update_current_branch()
+    if args.suffix != "" and args.last_commit is None:
+        logging.error('--suffix requires --last-commit')
+        sys.exit(1)
+    update_current_branch(None, args.suffix, args.last_commit,
+                          args.exclude_branch)
 else:
+    if args.suffix != "" or args.last_commit is not None \
+       or update_current_branch is not None:
+        logging.error('--suffix, --last-commit and --exclude-branch '
+                      'require --current')
+        sys.exit(1)
     for ref in origin.refs:
         assert ref.name.startswith('origin/')
         name = ref.name[len('origin/'):]
@@ -189,7 +223,7 @@ else:
             branch.checkout()
             origin.pull(rebase=True)
             logging.info('branch pulled and checked out')
-            update_current_branch(name)
+            update_current_branch(name, args.suffix)
             assert not repo.index.diff(None)
             logging.info('branch is done')
             logging.info('')