[CI] Enable clang-tidy in precommit

.github/workflows/sycl-clang-tidy.yml

@@ -0,0 +1,80 @@
+name: clang-tidy
+
+on:
+  workflow_call:
+
+permissions: read-all
+
+jobs:
+  run-clang-tidy:
+    runs-on: [Linux, build]
+    container:
+      image: ghcr.io/intel/llvm/sycl_ubuntu2404_nightly:latest
+      options: -u 1001:1001
+    steps:
+      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+        with:
+          sparse-checkout: |
+            devops/actions
+            devops/scripts
+      - name: Register cleanup after job is finished
+        uses: ./devops/actions/cleanup
+
+      - name: Check diff
+        id: should_run_tidy
+        run: |
+          echo "Downloading the diff"
+          curl -L "${{ github.server_url }}/${{ github.repository }}/pull/${{ github.event.pull_request.number }}.diff" -o pr.diff
+
+          if python3 devops/scripts/should_run_clang-tidy.py pr.diff; then
+            echo "run=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "run=false" >> "$GITHUB_OUTPUT"
+          fi
+
+      - if: steps.should_run_tidy.outputs.run == 'true'
+        uses: ./devops/actions/cached_checkout
+        with:
+          path: src
+          ref: ${{ github.sha }}
+          cache_path: "/__w/repo_cache/"
+      - name: Configure
+        if: steps.should_run_tidy.outputs.run == 'true'
+        env:
+          CC: gcc
+          CXX: g++
+          CUDA_LIB_PATH: "/usr/local/cuda/lib64/stubs"
+        run: |
+          mkdir -p $GITHUB_WORKSPACE/build
+          cd $GITHUB_WORKSPACE/build
+          python3 $GITHUB_WORKSPACE/src/buildbot/configure.py -w $GITHUB_WORKSPACE \
+            -s $GITHUB_WORKSPACE/src -o $GITHUB_WORKSPACE/build -t Release \
+            --ci-defaults -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
+
+      - name: Preprocess compile_commands.json
+        if: steps.should_run_tidy.outputs.run == 'true'
+        run: |
+          # Remove commands containing "-D__INTEL_PREVIEW_BREAKING_CHANGES" to avoid running on the same file twice.
+          jq '[ .[] | select(.command | contains("-D__INTEL_PREVIEW_BREAKING_CHANGES") | not) ]' $GITHUB_WORKSPACE/build/compile_commands.json > $GITHUB_WORKSPACE/build/compile_commands.temp.json
+          mv $GITHUB_WORKSPACE/build/compile_commands.temp.json $GITHUB_WORKSPACE/build/compile_commands.json
+
+          # Remove gcc-specific flags
+          perl -0777 -pe '
+            s/(?:^|[ \t])\-Wno-class-memaccess(?=$|[ \t])//g;
+            s/(?:^|[ \t])\-Wno-dangling-reference(?=$|[ \t])//g;
+            s/(?:^|[ \t])\-Wno-stringop-overread(?=$|[ \t])//g;
+            s/[ \t]{2,}/ /g;
+          ' -i  $GITHUB_WORKSPACE/build/compile_commands.json
+
+      - name: Run clang-tidy on modified files
+        if: steps.should_run_tidy.outputs.run == 'true'
+        # Exeprimental workflow, it won't affect the pre-commit status in case of failure.
+        continue-on-error: true
+        run: |
+          cd "$GITHUB_WORKSPACE/src"
+          python3 "$GITHUB_WORKSPACE/src/clang-tools-extra/clang-tidy/tool/clang-tidy-diff.py" \
+            -clang-tidy-binary "/opt/sycl/bin/clang-tidy" \
+            -p 1 \
+            -path "$GITHUB_WORKSPACE/build" \
+            -checks "clang-analyzer-*,bugprone-*,performance-*,-bugprone-std-namespace-modification" \
+            < "$GITHUB_WORKSPACE/pr.diff"

.github/workflows/sycl-linux-precommit.yml

@@ -68,6 +68,10 @@ jobs:
       e2e_binaries_preview_artifact: e2e_bin_preview
       e2e_binaries_new_offload_model_artifact: e2e_bin_new_offload_model
 
+  clang-tidy:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'disable-lint') }}
+    uses: ./.github/workflows/sycl-clang-tidy.yml
+
   # Build and run native cpu e2e tests separately as cannot currently
   # build all the e2e tests
   build_run_native_cpu_e2e_tests:

devops/scripts/should_run_clang-tidy.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+
+# This script checks if a diff contains changes that should be inspected by
+# clang-tidy.
+
+from __future__ import annotations
+import re
+import sys
+from typing import Iterator
+
+EXCLUDE_PATH_RE = re.compile(r"(?:^|/)(test|test-e2e|unittests)(?:/|$)")
+
+
+def is_relevant_path(path: str) -> bool:
+    return EXCLUDE_PATH_RE.search(path) is None
+
+
+# This iterator splits a diff  file into separate sections like:
+# diff --git a/path-to/file b/path-to/file
+# ... code changes ...
+def iter_diff_sections(diff_content: str) -> Iterator[str]:
+    section_lines: list[str] = []
+    started = False
+
+    for line in diff_content.splitlines(True):  # keep '\n'
+        if line.startswith("diff --git "):
+            if started and section_lines:
+                yield "".join(section_lines)
+                section_lines = []
+            started = True
+
+        if started:
+            section_lines.append(line)
+
+    if started and section_lines:
+        yield "".join(section_lines)
+
+
+def main() -> int:
+    diff_path = sys.argv[1]
+    with open(diff_path, "r", encoding="utf-8", errors="replace") as f:
+        diff_content = f.read()
+
+    should_run = False
+    for section in iter_diff_sections(diff_content):
+        lines = section.splitlines()
+        # Skip removed files.
+        if lines[4] == "+++ /dev/null":
+            continue
+        result_file = lines[3]
+        # Skip non-c++ files.
+        if not result_file.endswith((".cpp", ".hpp", ".h")):
+            continue
+        # Skip tests etc.
+        if not is_relevant_path(result_file):
+            continue
+        # Check if any non-comment string was added.
+        for line in lines[4:]:
+            if line.startswith("+") and not line[1:].lstrip().startswith("//"):
+                should_run = True
+                break
+        if should_run == True:
+            break
+
+    sys.exit(0 if should_run else 1)
+
+
+if __name__ == "__main__":
+    sys.exit(main())