| commit | e3d920699c6df959f3e0844aeadd983b2955b23e | [log] [tgz] |
|---|---|---|
| author | Dan Gohman <gohman@apple.com> | Thu Aug 07 02:54:50 2008 +0000 |
| committer | Dan Gohman <gohman@apple.com> | Thu Aug 07 02:54:50 2008 +0000 |
| tree | 7578dc6bd96037d61f965d03bac25fbe96259ad7 | |
| parent | 865db4566e84b788e5738fec462804a779223b8b [diff] |
Re-enable elimination of unnecessary SUBREG_TO_REG instructions in LowerSubregs, and fix an x86-64 isel bug that this exposed. SUBREG_TO_REG for x86-64 implicit zero extension is only safe for isel to generate when the source is known to always have zeros in the high 32 bits. The EXTRACT_SUBREG instruction does not clear the high 32 bits. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54444 91177308-0d34-0410-b5e6-96231b3b80d8