commit | 3112581441cd22ac955b1af2d08effe3bab975da | [log] [tgz] |
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author | Dan Gohman <gohman@apple.com> | Sat Mar 07 01:58:32 2009 +0000 |
committer | Dan Gohman <gohman@apple.com> | Sat Mar 07 01:58:32 2009 +0000 |
tree | 75390e19a279468681deb75b5286359ae3a3e714 | |
parent | 4b5051b0f91c35fed0d0d443ae435c51147d3d03 [diff] |
Arithmetic instructions don't set EFLAGS bits OF and CF bits the same say the "test" instruction does in overflow cases, so eliminating the test is only safe when those bits aren't needed, as is the case for COND_E and COND_NE, or if it can be proven that no overflow will occur. For now, just restrict the optimization to COND_E and COND_NE and don't do any overflow analysis. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66318 91177308-0d34-0410-b5e6-96231b3b80d8