On Mon, 26 Feb 2024 13:24:05 GMT, Emanuel Peter <epe...@openjdk.org> wrote:
>> To avoid invariant initializations to happen within the loop, compiler will >> unroll this small loop and will forward the initializations, if it does not >> then we can save redundant allocation within loop. > > At the risk of becoming too nit-picky: which allocations are you talking > about? Given you only have a single src and a single dst for this label/jump. > So you won't use `_patch_overflow`. And therefore, all allocations are on the > stack. The way you do it now, it seems you would allocate 4x the stack memory > here, compared to doing it locally in the loop, where the stack space could > potentially be reused between the iterations. > It seems to me this is an optimization at the cost of code-style. Having them > local makes it more clear that you are only jumping inside a iteration, and > not between iterations. I could not find any other case with the same pattern, of initializing a list of Labels. On the other hand, I can find cases where we already do what I am saying: `C2_MacroAssembler::rtm_counters_update` ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/16354#discussion_r1502617942
