On 7 December 2015 at 14:53, Edward Nevill <edward.nev...@linaro.org> wrote: >> adrp, x0, dest >> add x0, x0, #:lo12:dest > > Thanks! Thats the syntax I wanted. > > The use case is I want to benchmark this as a way of generating far > calls, for use within the JIT for when code cache becomes > 128m. > > At the moment we generate trampolines > > tramp: > ldr Xn, here > br Xn > here > .dword dest > > and then do > > bl dest > > but if on relocation in the code cache it doen't reach then relocate this to > > bl tramp > > but I think it may be better to simply always generate > > adrp Xn, dest > add Xn, Xn, :lo12:dest > blr Xn >
I don't suppose the branch predictor would like that very much, though. Can't you keep the original arrangement, and use this sequence instead? Or use the new sequence unconditionally, but nop out the add instruction and change the blr for a straight bl if the target is in range? _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org https://lists.linaro.org/mailman/listinfo/linaro-dev
