Messages in this thread | | | From | Andy Lutomirski <> | Date | Fri, 6 Jun 2014 14:44:51 -0700 | Subject | Re: [GIT PULL] x86/vdso changes for v3.16 |
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On Fri, Jun 6, 2014 at 2:42 PM, H. Peter Anvin <hpa@zytor.com> 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 <luto@amacapital.net>
The generated vdso-image-*.c files are identical.
--Andy
> > -hpa >
-- Andy Lutomirski AMA Capital Management, LLC
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