Andres Freund <and...@anarazel.de> writes: > On March 25, 2017 4:56:11 PM PDT, Ants Aasma <ants.aa...@eesti.ee> wrote: >> I haven't had the time to research this properly, but initial tests >> show that with GCC 6.2 adding >> >> #pragma GCC optimize ("no-crossjumping") >> >> fixes merging of the op tail jumps. >> >> Some quick and dirty benchmarking suggests that the benefit for the >> interpreter is about 15% (5% speedup on a workload that spends 1/3 in >> ExecInterpExpr). My idea of prefetching op->resnull/resvalue to local >> vars before the indirect jump is somewhere between a tiny benefit and >> no effect, certainly not worth introducing extra complexity. Clang 3.8 >> does the correct thing out of the box and is a couple of percent >> faster than GCC with the pragma.
> That's large enough to be worth doing (although I recall you seeing all jumps > commonalized). We should probably do this on a per function basis however > (either using pragma push option, or function attributes). Seems like it would be fine to do it on a per-file basis. If you're worried about pessimizing the out-of-line subroutines, we could move those to a different file --- it's pretty questionable that they're in execExprInterp.c in the first place, considering they're meant to be used by more than just that execution method. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers