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SiByte 1480 & Branch Likely instructions?

To: <linux-mips@linux-mips.org>
Subject: SiByte 1480 & Branch Likely instructions?
From: "Kaz Kylheku" <kaz@zeugmasystems.com>
Date: Fri, 7 Dec 2007 13:54:30 -0800
Original-recipient: rfc822;linux-mips@linux-mips.org
Sender: linux-mips-bounce@linux-mips.org
Thread-index: Acg5G75nLX9OzGDLQf6iiyb7ttVemw==
Thread-topic: SiByte 1480 & Branch Likely instructions?
Hi All,

Not really a kernel-related question. I've discovered that GCC 4.1.1
(which I'm not using for kernel compiling, but user space) generates
branch likely instructions by default, even though the documentation
says that their use is off by default for MIPS32 and MIPS64, because
they are considered deprecated. They are documented as obsolete for the
Broadcom chips I am working with.

I'm investigating a software anomaly which looks like might be caused by
failure to annul the delay slot of a branch-likely in the fall-through
case. 

In parallel with writing some tests, I thought I would ask whether
anyone happens know whether or not these instructions are known to
actually work correctly on the SB1480 silicon (and perhaps any
additional details, like what revisions, etc)?

Thanks

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