Implement Git hook for clang-formatting

[dorde-antic]

Motivation

Resolves https://github.com/ROCm/rocMLIR-internal/issues/1882

Technical Details

This PR introduces clang format in pre-commit hook. Temporarily, yapf part is disabled (by putting it as a comment) until refactored py files are merged. Therefore, pre-commit hook won't trigger yapf on py files changes (if there are some changes) when we want it to do only clang format.

Test Plan

Tested locally

Test Result

✅

Submission Checklist

• Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

[Copilot]

Pull Request Overview

This PR implements a Git pre-commit hook for clang-formatting C/C++ files. It adds a Python utility to handle clang-format operations and integrates it into the existing pre-commit hook workflow.

• Adds a new Python utility (clangformat.py) that wraps git-clang-format functionality
• Updates the pre-commit hook to run clang-format on C/C++ files in addition to the existing yapf formatting for Python files
• Adds error handling and validation for required tools (yapf and clang-format)

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
mlir/utils/widgets/clangformat.py	New Python utility providing clang-format integration with Git workflow
.githooks/pre-commit	Updated pre-commit hook to include clang-format execution and improved tool validation

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[justinrosner]

Right now our CI gives us a way to turn off formatting for external LLVM files that we don't necessarily want to format. Do we have a way of implementing this kind of logic here?

[dorde-antic]

Yes, we can exclude external llvm files (same as we did for yapf) @justinrosner

[dorde-antic]

Todo: uncomment yapf part since it's now being used

Test: if both cpp and py files are changed and separate cases only

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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[Copilot]

This conditional check always prints the message when there are cached changes, but doesn't provide actionable information. Since the files are already staged by line 45, this check is redundant. Consider removing this block or making it informative by indicating which files were modified.

Suggested change

	if ! git diff --cached --quiet -- "${cxxfiles[@]}"; then
	echo "Applied clang-format changes and staged them."
	# List files that were modified and staged by clang-format
	changed_cxxfiles=$(git diff --cached --name-only -- "${cxxfiles[@]}")
	if [[ -n "$changed_cxxfiles" ]]; then
	echo "Applied clang-format changes and staged the following files:"
	echo "$changed_cxxfiles"