3 Commits

Author	SHA1	Message	Date
Evan Cheng	2afc417122	Re-enable extension optimization pass. ... llvm-svn: 93313	2010-01-13 08:45:40 +00:00
Evan Cheng	973fceab0c	Disable opt-ext pass to unbreak the build for now. ... llvm-svn: 93286	2010-01-13 01:51:43 +00:00
Evan Cheng	76db3bb18e	Add a quick pass to optimize sign / zero extension instructions. For targets where the pre-extension values are available in the subreg of the result of the extension, replace the uses of the pre-extension value with the result + extract_subreg. ... For now, this pass is fairly conservative. It only perform the replacement when both the pre- and post- extension values are used in the block. It will miss cases where the post-extension values are live, but not used. llvm-svn: 93278	2010-01-13 00:30:23 +00:00