[infra] Support extra arguments for llvm-cov + update the binaries. (#1629)

* [infra] Support extra arguments for llvm-cov + update the binaries.

* Slightly change the doc to be less confusing.

docs/code_coverage.md

@@ -72,6 +72,17 @@ via `--corpus-dir` to be used instead of the corpus downloaded from OSS-Fuzz:
 python infra/helper.py profile --fuzz-target=<fuzz_target_name> --corpus-dir=<my_local_corpus_dir> $project_name
 ```
 
+### Additional arguments for `llvm-cov`
+
+You may want to use some of the options of [llvm-cov tool], for example,
+`-ignore-filename-regex=` or `-tab-size=`. You can pass those to the helper
+script after `--`:
+
+```bash
+python infra/helper.py profile $project_name -- -ignore-filename-regex='.*code/to/be/ignored/.*' -tab-size=2
+```
+
 
 [Clang Source-based Code Coverage]: https://clang.llvm.org/docs/SourceBasedCodeCoverage.html
 [gsutil tool]: https://cloud.google.com/storage/docs/gsutil_install
+[llvm-cov tool]: https://llvm.org/docs/CommandGuide/llvm-cov.html

infra/base-images/base-runner/coverage

@@ -23,7 +23,10 @@ else
 fi
 
 LOGS_DIR="$OUT/logs"
-mkdir -p $LOGS_DIR
+rm -rf $LOGS_DIR && mkdir -p $LOGS_DIR
+
+REPORT_DIR="$OUT/report"
+rm -rf $REPORT_DIR
 
 # This will be used by llvm-cov command to generate the actual report.
 objects=""
@@ -75,10 +78,10 @@ rm *.profraw
 # TODO(mmoroz): add script from Chromium for rendering directory view reports.
 
 # Generate HTML report.
-llvm-cov show -format=html -output-dir=report -path-equivalence="/,$OUT" \
-		-instr-profile merged.profdata $objects
+llvm-cov show -format=html -output-dir=$REPORT_DIR -path-equivalence="/,$OUT" \
+    $COVERAGE_EXTRA_ARGS -instr-profile merged.profdata $objects
 
 # Serve the report locally.
 echo "Serving the report on http://127.0.0.1:$HTTP_PORT/"
-cd report
+cd $REPORT_DIR
 python3 -m http.server $HTTP_PORT

infra/helper.py

@@ -122,7 +122,6 @@ def main():
 
   profile_parser = subparsers.add_parser(
       'profile', help='Generate code coverage report for the project.')
-  profile_parser.add_argument('project_name', help='name of the project')
   profile_parser.add_argument('--no-corpus-download', action='store_true',
                               help='do not download corpus backup from OSS-Fuzz; '
                               'use corpus located in build/corpus/<project>/<fuzz_target>/')
@@ -132,6 +131,9 @@ def main():
                               'target to be run for generating coverage report')
   profile_parser.add_argument('--corpus-dir', help='specify location of corpus '
                               'to be used (requires --fuzz-target argument)')
+  profile_parser.add_argument('project_name', help='name of the project')
+  profile_parser.add_argument('extra_args', help='additional arguments to '
+                              'pass to llvm-cov utility.', nargs='*')
 
   reproduce_parser = subparsers.add_parser(
       'reproduce', help='Reproduce a crash.')
@@ -621,6 +623,7 @@ def profile(args):
       'PROJECT=%s' % args.project_name,
       'SANITIZER=profile',
       'HTTP_PORT=%s' % args.port,
+      'COVERAGE_EXTRA_ARGS=%s' % ' '.join(args.extra_args),
   ]
 
   run_args = _env_to_docker_args(env)