On Fri, Apr 13, 2018 at 12:10:33PM +0000, Wilco Dijkstra wrote: > > Anyway, here is what I think Richard was asking for, that I'm currently > > bootstrapping/regtesting. It can be easily combined with Martin's target > > hook if needed, or do it only for > > endp == 1 && target != const0_rtx && CALL_EXPR_TAILCALL (exp) > > This patch causes regressions on AArch64 since it now always calls mempcpy > again, so yes either it would need to be done only for tailcalls (which fixes > the
No, it only uses mempcpy if we'd otherwise call memcpy library function and user wrote mempcpy. AFAIK 7.x and earlier behaved that way too, so it isn't a regression, regression is only from released GCC versions. And, a fix is easy, just implement fast mempcpy on aarch64 ;) Jakub