Re: [PATCH 1/2] x86: optimize XCHG to MOV for same-register forms
"H.J. Lu" <[email protected]>
| Newsgroups | gmane.comp.debugging.valgrind.devel,gmane.comp.gnu.binutils |
|---|---|
| Message-ID | <CAMe9rOq98WkhTBBXyAu_LHjxaresYihVRCjcv+ue=ybRBZERZg@mail.gmail.com> |
On Tue, Jul 7, 2026 at 1:53 PM Jan Beulich <[email protected]> wrote: > > On 06.07.2026 23:12, H.J. Lu wrote: > > We should consider benefits vs drawbacks for this optimization. Do we have > > a list of applications which benefit from this optimization? > > This question was raised before (in different words), and the answer is still > the same - how could we possibly know? The same is true though for about any > other of the optimizations we meanwhile have. IOW to me that's _still_ not a > viable criteria to work from. For assembler optimizations, we can give them benefits of doubt. Since we now know there is a significant drawback, its benefits should outweigh its drawbacks to enable this optimization. We can't assume that this optimization improves anything without evidence. -- H.J. _______________________________________________ Valgrind-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/valgrind-developers