On 04/02/10 05:26, Steven Bosscher wrote:
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).
And that rewrite would use standard, well known & understood dependence
analysis. reorg's methods for determine what insns can go into delay
slots is utterly insane and can get extremely expensive.
jeff
