From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <36de4d46283ce3f7afeed7cf21c23271@hamnavoe.com>
To: 9fans@9fans.net
From: Richard Miller <9fans@hamnavoe.com>
Date: Wed, 30 Jan 2013 10:35:56 +0000
In-Reply-To: <d1329b9babc534669c4b183f34394a01@kw.quanstro.net>
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Subject: Re: [9fans] emulated fp on arm
Topicbox-Message-UUID: 11c8e032-ead8-11e9-9d60-3106f5b1d025

> ARM 	-1 + 1 = -0 cmp 0 fail; cmp -0 fail
> 	1 + -1 = 0 cmp 0 ok; cmp -0 ok

I know floating point add isn't associative, but I thought it was at
least meant to be commutative.  The bug may not be where you think.

> the fpi guts are independent of the emulation on top, aren't they?

More or less.  There's the question of how many secret extra bits
of precision to maintain internally, beyond the ones you get when
you store from a register.