From: roy rosen <roy.1rosen@gmail.com>
To: Richard Guenther <richard.guenther@gmail.com>
Cc: gcc@gcc.gnu.org
Subject: Re: vectorization, scheduling and aliasing
Date: Tue, 27 Apr 2010 08:04:00 -0000 [thread overview]
Message-ID: <o2zbba479b11004270057o57d4b9a2ndde26e75ec98b60@mail.gmail.com> (raw)
In-Reply-To: <m2s84fc9c001004260731s9a185937l10c2f703ac94846f@mail.gmail.com>
Hi,
I have looked a bit more and tried also ia-64 and bfin and actually I
can't find a single example where vectorized code using __restrict__
variables would break the dependency between stores and loads.
for this simple program:
unsigned short xxx(unsigned short* __restrict__ a, unsigned short*
__restrict__ b)
{
int i;
for (i = 0; i < 8; i++)
{
a[i] = b[i];
}
return 0;
}
After unrolling and vectorization I get for all architectures that
there is a dependency between the first store (to a) and the second
load (from b).
since these are restrict variables I think this behavior is incorrect.
Can someone please show me such an example? Or is this feature not yet
supported?
Thanks, Roy.
prev parent reply other threads:[~2010-04-27 7:57 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-14 8:40 roy rosen
2010-04-14 11:07 ` Richard Guenther
2010-04-22 16:22 ` roy rosen
2010-04-23 12:12 ` Richard Guenther
2010-04-26 7:57 ` roy rosen
2010-04-26 11:24 ` Richard Guenther
2010-04-26 13:51 ` roy rosen
2010-04-26 14:34 ` Richard Guenther
2010-04-27 8:04 ` roy rosen [this message]
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