Commit Graph

3 Commits

Author SHA1 Message Date
Evan Cheng
a5e1362f96 Revert r122955. It seems using movups to lower memcpy can cause massive regression (even on Nehalem) in edge cases. I also didn't see any real performance benefit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123015 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-07 19:35:30 +00:00
Evan Cheng
461f1fc359 Use movups to lower memcpy and memset even if it's not fast (like corei7).
The theory is it's still faster than a pair of movq / a quad of movl. This
will probably hurt older chips like P4 but should run faster on current
and future Intel processors. rdar://8817010


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122955 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-06 07:58:36 +00:00
Evan Cheng
a57fabe815 Coalescer should not delete copy instructions whose defs are partially dead. e.g.
%RDI<def,dead> = MOV64rr %RAX<kill>, %EDI<imp-def>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100804 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 20:02:37 +00:00