On Fri, Jun 6, 2014 at 2:42 PM, H. Peter Anvin <[email protected]> wrote: > On 06/06/2014 02:39 PM, Andy Lutomirski wrote: >>> >>> For accessing memory members doing it via a pointer is pretty much TRT, >>> but for things that might be in register it is undesirable to force it >>> out to memory. >> >> Do you also believe in the folklore that GCC can optimize code >> sequences like the things in that header? Because I'm pretty sure >> that no clang or gcc version I've ever seen can do it. >> > > I have seen gcc do some pretty sophisticated memory elision lately. > Don't know if that includes byte swaps. > >> On the other hand, even a factor of ten in the time it takes to run >> vdso2c is completely irrelevant. > > Yep, as I noted in the patch I sent (which is broken - updated one > included here.)
Acked-by: Andy Lutomirski <[email protected]> The generated vdso-image-*.c files are identical. --Andy > > -hpa > -- Andy Lutomirski AMA Capital Management, LLC -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
