Commit Graph

2 Commits

Author SHA1 Message Date
Chris Lattner
85b5eb0505 Fix folding of icmp's of i1 where the comparison is signed. The code
was using the algorithm for folding unsigned comparisons which is
completely wrong.  This has been broken since the signless types change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53444 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 04:20:58 +00:00
Chris Lattner
f299184565 Fix a bogus optimization: folding (slt (zext i1 A to i32), 1) -> (slt i1 A, true)
This cause a regression in InstCombine/JavaCompare, which was doing the right
thing on accident.  To handle the missed case, generalize the comparisons based
on masked bits a little bit to handle comparisons against the max value. For 
example, we can now xform (slt i32 (and X, 4), 4) -> (setne i32 (and X, 4), 4)




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53443 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 04:09:09 +00:00