[lkml]   [2017]   [Mar]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Question Regarding ERMS memcpy
On March 4, 2017 4:33:49 PM PST, Borislav Petkov <> wrote:
>On Sat, Mar 04, 2017 at 04:23:17PM -0800, wrote:
>> What are the compilation flags? It may be that gcc still does TRT
>> depending on this call site. I'd check what gcc6 or 7 generates,
>> though.
>Well, I don't think that matters: if you're building a kernel on one
>machine to boot on another machine, the compiler can't know at build
>time what the best MOVS* variant would be for the target machine.
>why we're doing the alternatives patching at *boot* time.
>However, if the size is small enough, the CALL/patch overhead would be
>definitely too much.
>Hmm, I wish we were able to say, "let gcc decide for small sizes and
>us do the patching for larger ones."

That's what the -march= and -mtune= option do!
Sent from my Android device with K-9 Mail. Please excuse my brevity.

 \ /
  Last update: 2017-03-05 01:57    [W:10.029 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site