[llvm-branch-commits] [UTC] Strip only standalone positional %s in update_test_checks.py (PR #221153)

[Vitaly Buka via llvm-branch-commits]

https://github.com/vitalybuka created https://github.com/llvm/llvm-project/pull/221153

Previously, update_test_checks.py used tool_cmd_args.replace("%s", "")
to strip the input file when passing the IR via stdin. However, this
blindly removed "%s" from any option argument (such as
-lowertypetests-read-summary=%s or other pass options taking %s), leaving
an empty value and causing the tool to fail to load expected input files.

Update the argument stripping to only remove standalone positional
"< %s" or "%s", preserving option arguments with "%s" values so they can
be expanded via common substitutions.

Assisted-by: Gemini