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Re: Modes on CONST_INTs
- To: hans-peter dot nilsson at axis dot com
- Subject: Re: Modes on CONST_INTs
- From: Geoff Keating <geoffk at geoffk dot org>
- Date: Mon, 27 Nov 2000 14:56:02 -0800
- CC: hans-peter dot nilsson at axis dot com, bernds at redhat dot com, gcc at gcc dot gnu dot org
- References: <200011272033.VAA03226@ignucius.axis.se>
- Reply-to: Geoff Keating <geoffk at redhat dot com>
> Date: Mon, 27 Nov 2000 21:33:54 +0100
> From: Hans-Peter Nilsson <hans-peter.nilsson@axis.com>
> Right. Also, having the signedness/unsignedness property
> available would find more bugs, as Michael Meissner pointed out.
> You can't really have a canonical representation of a number
> unless you know how it was used. Currently we have two
> representations, for example both 255 and -1 for
> all-bits-in-a-byte to track that, with inevitable bugs like the
> ones at the URL; "QImode/U -1" might be an alternative.
No, we only have one. All the 255 occurrences in the RTL are wrong.
--
- Geoffrey Keating <geoffk@geoffk.org>