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| author | Chris Lattner <sabre@nondot.org> | 2003-02-06 19:39:21 +0000 |
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| committer | Chris Lattner <sabre@nondot.org> | 2003-02-06 19:39:21 +0000 |
| commit | b71310982a1782f435e3836c8b9bdc489d4135e2 (patch) | |
| tree | 00c2897523ee05a2dd15d17f4053b9ac0ea38016 /docs/OpenProjects.html | |
| parent | 5d2745801c9585780228553377b984810f4f5e73 (diff) | |
| download | llvm-b71310982a1782f435e3836c8b9bdc489d4135e2.tar.gz llvm-b71310982a1782f435e3836c8b9bdc489d4135e2.tar.bz2 llvm-b71310982a1782f435e3836c8b9bdc489d4135e2.tar.xz | |
New "open projects" document
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5497 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs/OpenProjects.html')
| -rw-r--r-- | docs/OpenProjects.html | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/docs/OpenProjects.html b/docs/OpenProjects.html new file mode 100644 index 0000000000..b79c0aae92 --- /dev/null +++ b/docs/OpenProjects.html @@ -0,0 +1,287 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html><head><title>Open LLVM Projects</title></head> + +<body bgcolor=white> +<center><h1><font size=7>Open LLVM Projects</font></h1></center> + +<ul> + <li><a href="#what">What is this?</a> + <li><a href="#improving">Improving the current system</a> + <ol> + <li><a href="#glibc">Port glibc to LLVM</a> + <li><a href="#NightlyTest">Improving the Nightly Tester</a> + <li><a href="#programs">Compile programs with the LLVM Compiler</a> + <li><a href="#llvm_ir">Extend the LLVM intermediate representation</a> + <li><a href="#misc_imp">Miscellaneous Improvements</a> + </ol> + + <li><a href="#new">Adding new capabilities to LLVM</a> + <ol> + <li><a href="#pointeranalysis">Pointer and Alias Analysis</a> + <li><a href="#profileguided">Profile Guided Optimization</a> + <li><a href="#xforms">New Transformations and Analyses</a> + <li><a href="#x86be">X86 Back-end Improvements</a> + <li><a href="#misc_new">Miscellaneous Additions</a> + </ol> +</ul> + +<br><br> + +<!-- *********************************************************************** --> +<table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0> +<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b> +<a name="what">What is this? +</b></font></td></tr></table><ul> +<!-- *********************************************************************** --> + +This document is meant to be a sort of "big TODO list" for LLVM. Each project +in this document is something that would be useful for LLVM to have, and would +also be a great way to get familiar with the system. Some of these projects are +small and self-contained, which may be implemented in a couple of days, others +are larger. Several of these projects may lead to interesting research projects +in their own right. In any case, we welcome all contributions.<p> + +If you are thinking about tackling one of these projects, please send a mail to +the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM +Developer's</a> mailing list, so that we know the project is being worked on. +Additionally this is a good way to get more information about a specific project +or to suggest other projects to add to this page.<p> + + +<!-- *********************************************************************** --> +</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0> +<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b> +<a name="improving">Improving the current system +</b></font></td></tr></table><ul> +<!-- *********************************************************************** --> + +Improvements to the current infrastructure are always very welcome and tend to +be fairly straight-forward to implement. Here are some of the key areas that +can use improvement...<p> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="glibc">Port glibc to LLVM +</b></font></td></tr></table><ul> + +It would be very useful to <a +href="http://www.gnu.org/software/libc/porting.html">port</a> <a +href="http://www.gnu.org/software/glibc/">glibc</a> to LLVM. This would allow a +variety of interprocedural algorithms to be much more effective in the face of +library calls. The most important pieces to port are things like the string +library and the <tt>stdio</tt> related functions... low-level system calls like +'<tt>read</tt>' should stay unimplemented in LLVM.<p> + + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="NightlyTest">Improving the Nightly Tester +</b></font></td></tr></table><ul> + +The <a href="/testresults/">Nightly Tester</a> is a simple perl script (located +in utils/NightlyTest.pl) which runs every night to generate a daily report. It +could use the following improvements:<p> + +<ol> +<li>Olden timings - Time the compilation and execution times for the Olden + benchmark suite, keeping track of these values over time. + +<li>Graphs - It would be great to have gnuplot graphs to keep track of how the + tree is changing over time. We already gather a several statistics, it + just neccesary to add the script-fu to gnuplotize it. + +<li>Regression tests - We should run the regression tests in addition to the + program tests... +</ol><p> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="programs">Compile programs with the LLVM Compiler +</b></font></td></tr></table><ul> + +We are always looking for new testcases and benchmarks for use with LLVM. In +particular, it is useful to try compiling your favorite C source code with LLVM. +If it doesn't compile, try to figure out why or report it to the <a +href="http://mail.cs.uiuc.edu/pipermail/llvmbugs/">llvm-bugs</a> list. If you +get the program to compile, it would be extremely useful to convert the build +system to be compatible with the LLVM Programs testsuite so that we can check it +into CVS and the automated tester can use it to track progress of the compiler. + + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="llvm_ir">Extend the LLVM intermediate representation +</b></font></td></tr></table><ul> + +<ol> +<li>Transform <tt>setjmp</tt> and <tt>longjmp</tt> calls to use the LLVM + <tt>invoke</tt> mechanism. +<li>Add support for a volatile attribute on loads and stores +<li>Support for variable argument functions +<li>Add a new conditional move instruction: <tt>X = select bool Cond, Y, Z</tt> +<li>Add support for platform independant prefetch support. The GCC <a + href="http://gcc.gnu.org/projects/prefetch.html">prefetch project</a> page + has a good survey of the prefetching capabilities of a variety of modern + processors. +</ol> + + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="misc_imp">Miscellaneous Improvements +</b></font></td></tr></table><ul> + +<ol> +<li>Improve the efficiency of the bytecode loader/writer, allow streaming lazy + loading of functions from the bytecode (for use by the JIT, for example)<br> +<li>Rework the PassManager +<li>Do not encode zero intializers for large arrays into the bytecode + +<li>Some transformations and analyses only work on reducible flow graphs. It +would be nice to have a transformation which could be "required" by these passes +which makes irreducible graphs reducible. This can easily be accomplished +through code duplication. See <a +href="http://citeseer.nj.nec.com/janssen97making.html">Making Graphs Reducible +with Controlled Node Splitting</a> and perhaps <a +href="http://doi.acm.org/10.1145/262004.262005">Nesting of Reducible and +Irreducible Loops</a>. +</ol> + + +<!-- *********************************************************************** --> +</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0> +<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b> +<a name="new">Adding new capabilities to LLVM +</b></font></td></tr></table><ul> +<!-- *********************************************************************** --> + +Sometimes creating new things is more fun that improving existing things. These +projects tend to be more involved and perhaps require more work, but can also be +very rewarding.<p> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="pointeranalysis">Pointer and Alias Analysis +</b></font></td></tr></table><ul> + +We have a strong base for development of both pointer analysis based +optimizations as well as pointer analyses themselves. It seems natural to want +to take advantage of this...<p> + +<ol> +<li>Implement a flow-sensitive context-sensitive alias analysis algorithm<br> + - Pick one of the somewhat efficient algorithms, but strive for maximum + precision +<li>Implement a flow-sensitive context-insensitive alias anlaysis algorithm<br> + - Just an efficient local algorithm perhaps? + +<li>Implement an interface to update analyses in response to common code motion + transformations +<li>Implement alias analysis based optimizations: + <ul> + <li>Dead store elimination + <li>Location invariant Code Motion (LcICM) + <li>Store+Reload or "store forwarding" elimination:<p> + Change: + <pre> + store int X, int* P + Y = load int* P</pre> + into: + <pre> + store int X, int *P + Y = X</pre> + <li>Register promotion (move loads and stores out of loop bodies, for example) + </ul> +</ol> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="profileguided">Profile Guided Optimization +</b></font></td></tr></table><ul> + +We are getting to the point where we really need a unified infrastructure for +profile guided optimizations. It would be wonderful to be able to write profile +guided transformations which can be performed either at static compile time +(compile time or offline optimization time) or at runtime in a JIT type setup. +The LLVM transformation itself shouldn't need to know how it is being used.<p> + +Ideas for profile guided transformations:<p> + +<ol> +<li>Superblock formation (with many optimizations) +<li>Loop unrolling/peeling +<li>Profile directed inlining +<li>Code layout +<li>... +</ol><p> + + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="xforms">New Transformations and Analyses +</b></font></td></tr></table><ul> + +<ol> +<li>Implement a Dependence Analysis Infrastructure<br> + - Design some way to represent and query dep analysis +<li>Implement a faster Dominator Set Construction Algorithm<br> + - A linear time or nearly so algorithm +<li>Implement a strength reduction pass +<li>Value range propagation pass +<li>Implement a tail recursion elimination pass +<li>Implement an unswitching pass +</ol> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="x86be">X86 Back-end Improvements +</b></font></td></tr></table><ul> + +<ol> +<li>Implement a global register allocator +<li>Implement a better instruction selector +<li>Implement a static compiler in addition to the JIT (easy project) +</ol> + +<!-- ======================================================================= --> +</ul><table width="50%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0> +<tr><td> </td><td width=100%> +<font color="#EEEEFF" size=+1 face="Georgia,Palatino"><b> +<a name="misc_new">Miscellaneous Additions +</b></font></td></tr></table><ul> + +<ol> +<li>Write a new frontend for some language (Java? OCaml? Forth?) +<li>Write a new backend for a target (IA64? MIPS? MMIX?) +</ol> + + +<!-- *********************************************************************** --> +</ul> +<!-- *********************************************************************** --> + +<hr><font size-1> +<address><a href="mailto:sabre@nondot.org">Chris Lattner</a></address> +<!-- Created: Tue Aug 6 15:00:33 CDT 2002 --> +<!-- hhmts start --> +Last modified: Thu Feb 6 13:38:41 CST 2003 +<!-- hhmts end --> +</font></body></html> |