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Question about condition codes...
- From: "Mike Laman" <mlaman at cox dot net>
- To: "GCC" <gcc at gcc dot gnu dot org>
- Date: Mon, 4 Nov 2002 22:53:56 -0800
- Subject: Question about condition codes...
Hi,
I've looked at some implementations (md and c files). I'm trying to
understand
why the pdp11, mn10200, and v850 use the move instruction they say they
are a non_0hit and the condition code is not affected.
Also if they move a 0, they subtract the register from itself to zero the
value,
they clobber the condition codes.
What am I missing here? Why aren't the condition codes set by these moves
and move zeros to show the affects on the condition code bits insyead of
showing a no effect
I'm really misunderstanding something here.
Thanks,
Mike