Commit Graph

3 Commits

Author SHA1 Message Date
Nick Lewycky
5d52c4501a Revert r54876 r54877 r54906 and r54907. Evan found that these caused a 20%
slowdown in bzip2.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55113 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-21 05:56:10 +00:00
Nick Lewycky
91a0f78265 Consider the case where xor by -1 and xor by 128 have been combined already to
produce an xor by 127.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54906 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-17 19:58:24 +00:00
Nick Lewycky
1b344bc986 Xor'ing both sides of icmp by sign-bit is equivalent to swapping signedness of
the predicate.

Also, make this optz'n apply in more cases where it's safe to do so.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54876 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-17 07:34:14 +00:00