llvm-project

History

Nico Weber f6544934b9 Make check-llvm run 50% faster on macOS, 18% faster on Windows. While looking at cycle time graphs of some of my bots, I noticed that `327894859c` made check-llvm noticeably slower on macOS and Windows. As it turns out, the 5 substitutions added in that change were enough to cause lit to thrash the build-in cache in re.compile() (re.sub() is implemented as re.compile().sub()), and apparently applySubstitutions() is on the cricital path and slow when all regexes need to compile all the time. (See `_MAXCACHE = 512` in cpython/Lib/re.py) Supporting full regexes for lit substitutions seems a bit like overkill, but for now add a simple unbounded cache to recover the lost performance. No intended behavior change.		2020-01-06 12:57:42 -05:00
..
examples	Fix lit/example/many-tests pickling issue	2018-09-14 19:44:09 +00:00
lit	Make check-llvm run 50% faster on macOS, 18% faster on Windows.	2020-01-06 12:57:42 -05:00
tests	Fix buildbot failures after removing REQUIRES-ANY	2019-12-17 15:27:45 -06:00
utils	…
CMakeLists.txt	…
MANIFEST.in	lit: Make sure the builtin_commands directory is packaged by setup.py	2018-09-26 14:56:11 +00:00
README.txt	…
lit.py	[lit] Small cleanups. NFCI	2019-12-13 17:00:04 -08:00
setup.py	lit: Use a License classifier that pypi will accept	2019-08-08 17:23:33 +00:00

README.txt

===============================
 lit - A Software Testing Tool
===============================

lit is a portable tool for executing LLVM and Clang style test suites,
summarizing their results, and providing indication of failures. lit is designed
to be a lightweight testing tool with as simple a user interface as possible.

=====================
 Contributing to lit
=====================

Please browse the Test Suite > lit category in LLVM's Bugzilla for ideas on
what to work on.

Before submitting patches, run the test suite to ensure nothing has regressed:

    # From within your LLVM source directory.
    utils/lit/lit.py \
        --path /path/to/your/llvm/build/bin \
        utils/lit/tests

Note that lit's tests depend on 'not' and 'FileCheck', LLVM utilities.
You will need to have built LLVM tools in order to run lit's test suite
successfully.

You'll also want to confirm that lit continues to work when testing LLVM.
Follow the instructions in http://llvm.org/docs/TestingGuide.html to run the
regression test suite:

    make check-llvm

And be sure to run the llvm-lit wrapper script as well:

    /path/to/your/llvm/build/bin/llvm-lit utils/lit/tests

Finally, make sure lit works when installed via setuptools:

    python utils/lit/setup.py install
    lit --path /path/to/your/llvm/build/bin utils/lit/tests