35a8988d50
In previous allmodules&autoloading patch, we used callback from DeserializationListener to get Decl and loaded corresponding libraries. It worked, but the performance was bad because ROOT was loading excessive libraries. In this patch, we use TCling::LazyFunctionCreatorAutoloadForModule. This function gets callback when "mangled_name" was not found in loaded libraries thus we have to the load corresponding library and lookup again. I used unordered_map to store mangled identifier and library pair. I'm doing an optimization by hashing mangled name and storing library not by name but by uint8 and hold uint8-name information in another vector. Also tried std::map but unorderd_map was more performant. There are better hash table like: https://probablydance.com/2018/05/28/a-new-fast-hash-table-in-response-to-googles-new-fast-hash-table/ we can try to use them if this part gets crucial. With this patch: ``` Processing tutorials/hsimple.C... hsimple : Real Time = 0.04 seconds Cpu Time = 0.03 seconds (TFile *) 0x562b37a14fe0 Processing /home/yuka/CERN/ROOT/memory.C... cpu time = 0.362307 seconds sys time = 0.039741 seconds res memory = 278.215 Mbytes vir memory = 448.973 Mbytes ``` W/o this patch: ``` Processing tutorials/hsimple.C... hsimple : Real Time = 0.08 seconds Cpu Time = 0.07 seconds (TFile *) 0x5563018a1d30 Processing /home/yuka/CERN/ROOT/memory.C... cpu time = 1.524314 seconds sys time = 0.157075 seconds res memory = 546.867 Mbytes vir memory = 895.184 Mbytes ``` So it improves time by 4x times and memory by 2x.
Cling - The Interactive C++ Interpreter
The main repository is at https://github.com/root-project/cling
Overview
Cling is an interactive C++ interpreter, built on top of Clang and LLVM compiler infrastructure. Cling realizes the read-eval-print loop (REPL) concept, in order to leverage rapid application development. Implemented as a small extension to LLVM and Clang, the interpreter reuses their strengths such as the praised concise and expressive compiler diagnostics.
See also cling's web page.
Please note that some of the resources are rather old and most of the stated limitations are outdated.
- talks
- http://blog.coldflake.com/posts/2012-08-09-On-the-fly-C++.html
- http://solarianprogrammer.com/2012/08/14/cling-cpp-11-interpreter/
- https://www.youtube.com/watch?v=f9Xfh8pv3Fs
- https://www.youtube.com/watch?v=BrjV1ZgYbbA
- https://www.youtube.com/watch?v=wZZdDhf2wDw
- https://www.youtube.com/watch?v=eoIuqLNvzFs
Installation
Release Notes
See our release notes to find what's new.
Binaries
Our nightly binary snapshots can be found here.
Building from Source with Cling Packaging Tool
Cling's tree has a user-friendly, command-line utility written in Python called Cling Packaging Tool (CPT) which can build Cling from source and generate installer bundles for a wide range of platforms. CPT requires Python 2.7 or later.
If you have Cling's source cloned locally, you can find the tool in
tools/packaging directory. Alternatively, you can download the script
manually, or by using wget:
wget https://raw.githubusercontent.com/root-project/cling/master/tools/packaging/cpt.py
chmod +x cpt.py
./cpt.py --check-requirements && ./cpt.py --create-dev-env Debug --with-workdir=./cling-build/
Full documentation of CPT can be found in tools/packaging.
Usage
./cling '#include <stdio.h>' 'printf("Hello World!\n")'
To get started run:
./cling --help
or type
./cling
[cling]$ .help
Jupyter
Cling comes with a Jupyter kernel. After building cling,
install Jupyter and run jupyter kernelspec install cling. It requires a fairly
new Jupyter. Make sure cling is in your PATH when you start jupyter!
See also the tools/Jupyter subdirectory for more information.
Developers' Corner
Cling's latest doxygen documentation
Contributions
Every contribution is considered a donation and its copyright and any other related rights become exclusive ownership of the person who merged the code or in any other case the main developers of the "Cling Project".
We warmly welcome external contributions to the Cling! By providing code, you agree to transfer your copyright on the code to the "Cling project". Of course you will be duly credited and your name will appear on the contributors page, the release notes, and in the CREDITS file shipped with every binary and source distribution. The copyright transfer is necessary for us to be able to effectively defend the project in case of litigation.
License
Please see our LICENSE.
Releases
Our release steps to follow when cutting a new release:
- Update release notes
- Remove
~devsuffix from VERSION - Add a new entry in the news section of our website
- Commit the changes.
git tag -a v0.x -m "Tagging release v0.x"- Create a draft release in github and copy the contents of the release notes.
- Wait for green builds.
- Upload binaries to github (Travis should do this automatically).
- Publish the tag and announce it on the mailing list.
- Increment the current version and append
~dev.