5 Commits

Author	SHA1	Message	Date
Jeff Cohen	8ea6f9e821	Fixed the following LSR bugs: ... * Loop invariant code does not dominate the loop header, but rather the end of the loop preheader. * The base for a reduced GEP isn't a constant unless all of its operands (preceding the induction variable) are constant. * Allow induction variable elimination for the simple case after all. Also made changes recommended by Chris for properly deleting instructions. llvm-svn: 20383	2005-03-01 03:46:11 +00:00
Jeff Cohen	dcaa48b5c4	Fix crash in LSR due to attempt to remove original induction variable. However, ... for reasons explained in the comments, I also deactivated this code as it needs more thought. llvm-svn: 20367	2005-02-28 00:08:56 +00:00
Jeff Cohen	fd63d3af0d	PHI nodes were incorrectly placed when more than one GEP is reduced in a loop. ... llvm-svn: 20360	2005-02-27 21:08:04 +00:00
Jeff Cohen	39751c3b7c	First pass at improved Loop Strength Reduction. Still not yet ready for prime time. ... llvm-svn: 20358	2005-02-27 19:37:07 +00:00
Nate Begeman	b18121e6a9	Initial implementation of the strength reduction for GEP instructions in ... loops. This optimization is not turned on by default yet, but may be run with the opt tool's -loop-reduce flag. There are many FIXMEs listed in the code that will make it far more applicable to a wide range of code, but you have to start somewhere :) This limited version currently triggers on the following tests in the MultiSource directory: pcompress2: 7 times cfrac: 5 times anagram: 2 times ks: 6 times yacr2: 2 times llvm-svn: 17134	2004-10-18 21:08:22 +00:00