lkml.org 
[lkml]   [2023]   [Sep]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 08/17] alpha: Implement xor_unlock_is_negative_byte
On Fri, 15 Sept 2023 at 11:37, Matthew Wilcox (Oracle)
<willy@infradead.org> wrote:
>
> + "1: ldl_l %0,%4\n"
> + " xor %0,%3,%0\n"
> + " xor %0,%3,%2\n"
> + " stl_c %0,%1\n"

What an odd thing to do.

Why don't you just save the old value? That double xor looks all kinds
of strange, and is a data dependency for no good reason that I can
see.

Why isn't this "ldl_l + mov %0,%2 + xor + stl_c" instead?

Not that I think alpha matters, but since I was looking through the
series, this just made me go "Whaa?"

Linus

\
 
 \ /
  Last update: 2023-09-16 02:30    [W:0.247 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site