From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Henderson <rth@twiddle.net>
Subject: Re: [PATCH] memory: use signed arithmetic
Date: Tue, 02 Aug 2011 14:59:47 -0700
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Cc: Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org,
	kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On 08/02/2011 01:50 PM, Avi Kivity wrote:
>  struct AddrRange {
> -    uint64_t start;
> -    uint64_t size;
> +    int64_t start;
> +    int64_t size;

I'm must say I'm not keen on this.  My primary objection is that
a "range" can no longer properly represent the entire address space.
Or, indeed, anything in the second half of it.

It sounds like your problem would be better solved by re-arranging
things such that you perform X < Y comparisons rather than DELTA < 0.



r~