On Fri, Apr 2, 2010 at 12:41 PM, Amker.Cheng <amker.ch...@gmail.com> wrote: >> The CFG is not maintained during delay slot scheduling. This is, in >> fact, a very old and well-known problem. Look for any e-mail on this >> list that mentions reorg.c :-) >> > Thanks, further more , It seems cfg are not maintained after delay > slot scheduling. > also find that problem just before final pass.
Yes. The CFG is constructed on GIMPLE and then maintained all the way through to reorg.c (or actually pass_free_cfg). Once destroyed, we cannot resurrect the CFG. In a perfect world, reorg.c would get a rewrite and we'd maintain the CFG all the way through to final. But in practice, reorg.c is not the only problem (for example, var-tracking also destroys the CFG, as do most machine reorgs). Ciao! Steven
