• SummerOfCode

Google's Summer Of Code

Thanks for your interest in the GNU Compiler Collection as your mentoring organization in Google's Summer of Code.

Summer of Code 2009 Accepted GCC Projects

Application

The Drupal project has a great page on How to write an SOC application. A gcc Summer of Code participant for 2006, Laurynas Biveinis, wrote a blog about it.

Project Ideas

There are several pages with general ideas for GCC. These ideas are not just one project but many different projects linked here for easy of access.

Relatively simple tasks:

• Ideas for speeding up GCC

• Improvements to GCC on Windows

• Partial_Transitions

• Improve the regression testing system, for example to detect places where the generated code changed (useful for refactoring).
• Fix -ftrapv so that it works.

New optimization passes:

• Implement code motion of stores towards entry (and use this to improve code for int to float conversion on rs6000-based targets)
• Implement a prototype for early instruction selection
• Propagate interprocedural dataflow from GIMPLE to RTL
• Propagate alias information from GIMPLE to RTL
• Improve support for the restrict qualifier
• Add Factored Use-Def (FUD) chains to RTL

• Loop optimizations and automatic parallelization based on Graphite ( Graphite Summer of Code ideas)

Language front-ends and run-time libraries:

• C++0x Support in GCC and libstdc++

• gcj, libgcj, and GNU Classpath ideas

• libstdc++ todo

• libstdc++ ideas

• Refactor libstdc++ for optional smaller footprint configuration, e.g., iostreams without templates

• Fortran front end: Unimplemented Fortran 2003 (and Fortran 2008) features, 4.5 plan and action list

• OpenMP 3.0 support and other runtime improvements: openmp

Other projects:

• Develop XML format to represent GCC optimization flow (function, loop, block enumeration) and IDE/visualization environment for fine-grain program optimization or tuning of the default GCC optimization heuristic

• Extend GCC generic function cloning to be able to create static binaries adaptable to different architectures at run-time (including multiple ISA generation). Cupertino Miranda has been extending this work recently and we may need to sync on that ... GCC function adaptation, GCC function specific optimization

• Extend GCC plugin framework/ICI/MILEPOST framework to enable fine-grain transformation parameter tuning. Currently we can perform search for good combination of passes, their orders and parameter tuning on function level and we would like to be able to do it for each individual transformation to tune optimization heuristic for Graphite loop transformations, loop vectorization, inlining, unrolling, etc. Maybe the project can be separated in several sub-projects to focus on some specific optimizations such as GRAPHITE/vectorization optimization heuristic tuning.

• Extend GCC plugin framework/ICI to enable code instrumentation (insert calls to external function after individual instructions) for dynamic code analysis. We need it to extend our TM/TLS models.
• Port and stabilize GCC4NET to the trunk together with the plugin system.
• Converting different program representation levels of GCC back to the source code. It's not a trivial task but I saw substantial interest to that recently.

• GCC projects page

• Separate the frontends from the middle-end (near bottom of page)

• Make -O2 (and other -On options) be a sum of individual -f* options, by adding a -fother-O2-optimizations (and same for other -On levels)
• When running the testsuite, run multiple tests in parallel
• Separate frontend folder from middle-end folder
• Emit debug information about types and declarations early (needed for LTO)
• Change the way thunks are emitted to be compatible with LTO

If you are interested in learning your way around the GCC codebase, the Partial_Transitions is a good place to start.

Other project ideas can be found in the bug database. Look for old bugs which are still open.

Or invent your own project. We're always open to good ideas. But note that we are probably not too interested in projects to add new extensions to the C or C++ languages. We've found over time that these tend to introduce more problems than they solve.

Thanks, and we look forward to your submissions!

Summer of Code 2008 Accepted GCC Projects

Summer of Code 2007 Accepted GCC Projects

Summer of Code 2006 Accepted GCC Projects