99263 2012-10-13 23:15:40 -0700 Structure checks that are hoisted should contribute their OSR exit profiling to the bytecode instructions that would have had the checks had they not been hoisted 2012-10-13 23:15:40 -0700 1 1 1 Unclassified WebKit JavaScriptCore 528+ (Nightly build) All All NEW P2 Normal --- 98606 1 fpizlo fpizlo barraclough ggaren mark.lam mhahnenberg msaboff oliver oldest_to_newest 741553 0 fpizlo 2012-10-13 23:15:40 -0700 Currently structure check hoisting almost completely breaks OSR exit profiling of structure checks. If a hoisted structure check fails, it only tells OSR exit profiling not to hoist that check in the future. But that implies that we might have to do one additional round of recompilation just to discover that we shouldn't have been emitting a structure check to begin with.