On Jun 17, 2011, at 10:21 AM, Tom Rodriguez wrote: >> >> Sorry, I was thinking recording which branch of the GWT is taken and >> storing them in the GWT. >> Two GWTs should not share the same metadata. > > This is the major problem with GWT/selectAlternative. Previously when GWT > was bytecodes we at least had a chance to get some profile information on > which way the branch was likely to go but with the ricochet frame version we > have no knowledge so each side of the if has equal probability. The were no > guarantees that the GWT would always be used as a fast/slow idiom but in > practice it was so we used to get good data. We'll have to find someway to > capture profiles for this if we can to treat fast/slow in a more aggressive > way.
selectAlternative has a branch profile. As long as GWT is being used as expected (for fast/slow splits), selectAlternative will have a fast/slow profile, just like the original GWT invokers. The PROB_FAIR in CallGenerator::for_method_handle_inline could be made "smarter", by feeding from the control inputs of the Phi; that would be a good start. -- John _______________________________________________ mlvm-dev mailing list mlvm-dev@openjdk.java.net http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev