On 12/10/13 00:01, bin.cheng wrote:
Emm, some kind of. See the cost of iv candidate set consists of several parts, the representation cost in cost pair; the register pressure cost falls in dependence on invariant expressions, etc.. Here iv_ca_has_deps checks whether new cost pair depends on other invariant expression which is not involved before, if so, current algorithm considers the new cost pair has higher cost and just skips. In fact, the new cost pair may give us lower overall cost even it introduces new dependence(similar to the case I gave). That's why I used the overall cost comparison for good.
OK. Thanks for the explanation.
Is this new version patch looks good to you? I will re-test if it's ok.
It does. Please do some final testing and it should be good to go. jeff
