Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1206951
| From | Linus Torvalds <torvalds@linux-foundation.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl |
| Date | 2015-08-13 18:30 +0200 |
| Message-ID | <pX3ya-92-27@gated-at.bofh.it> (permalink) |
| References | <pWU1P-3lW-1@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Wed, Aug 12, 2015 at 11:11 PM, George Spelvin <linux@horizon.com> wrote:
>
> Agreed. But some x86 code I'm working on now, I have a *lot* of
> asm("divl") calls because even do_div isn't great for 64/32->32 division.
Yeah.
I'm not convinced that "64/32->32" is all that generic, though. If
the dividend in 64-bit, there's no fundamental type-based guarantee
that things will fit.
So your case is rather special, and depends (intimately) on knowing
the actual ranges and how they interact.
That's not a generic situation like "do_div()".
Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl "George Spelvin" <linux@horizon.com> - 2015-08-13 08:20 +0200
Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl Linus Torvalds <torvalds@linux-foundation.org> - 2015-08-13 18:30 +0200
Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl "George Spelvin" <linux@horizon.com> - 2015-08-13 20:20 +0200
Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl Linus Torvalds <torvalds@linux-foundation.org> - 2015-08-13 20:30 +0200
Re: enabling libgcc for 64-bit divisions, was Re: PROBLEM: XFS on ARM corruption 'Structure needs cl "George Spelvin" <linux@horizon.com> - 2015-08-13 21:10 +0200
csiph-web