| commit | 506ed4d4a5ed65f40e1b2d4b68b5f79883c8c3fa | [log] [tgz] |
|---|---|---|
| author | Jonathan Roelofs <jonathan@codesourcery.com> | Wed Aug 20 23:38:50 2014 +0000 |
| committer | Jonathan Roelofs <jonathan@codesourcery.com> | Wed Aug 20 23:38:50 2014 +0000 |
| tree | 46ef139ddb0f4cd0754455bfe9a0709acf547179 | |
| parent | 400bc218f8798781ea2ff6eb63a5e017ea05d007 [diff] |
Lower thumbv4t & thumbv5 lo->lo copies through a push-pop sequence On pre-v6 hardware, 'MOV lo, lo' gives undefined results, so such copies need to be avoided. This patch trades simplicity for implementation time at the expense of performance... As they say: correctness first, then performance. See http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075998.html for a few ideas on how to make this better. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216138 91177308-0d34-0410-b5e6-96231b3b80d8