This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH] Use long for mantissa for generic mp code
On Tue, Feb 26, 2013 at 07:28:22PM -0800, Richard Henderson wrote:
> On 2013-02-26 18:07, Siddhesh Poyarekar wrote:
> >>>+/* Truncate IN to a multiple of F, where F is a power of two. */
> >>>>>+#define TRUNCATE_TO_MUL(in, f) ((in) & ~(f))
> >>>
> >>>Err, ~f? Either this doesn't work at all, or the comment is wrong.
> >Ugh, it should be ~(f - 1).
> >
>
> Er... we are talking about in % f, when we can't necessarily
> prove that F is a power of 2?
>
> Then no ~ at all, just (f-1).
Not % f, it's 'align down to F'. This will only work for F as a power
of two and not any other input. I didn't put any validation since
that'll just slow things down.
Siddhesh