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Re: patches to reorg.c for c4x
- To: law at cygnus dot com
- Subject: Re: patches to reorg.c for c4x
- From: Michael Hayes <m dot hayes at elec dot canterbury dot ac dot nz>
- Date: Thu, 01 Oct 1998 17:40:05 +1200 (NZST)
- Cc: Herman ten Brugge <Haj dot Ten dot Brugge at net dot HCC dot nl>, egcs-patches at cygnus dot com
- References: <"199809291822.TAA12533"@htbrug.net.HCC.nl><4239.907203662@hurl.cygnus.com>
Jeffrey A Law writes:
> My first question is how did we end up with an insn which sets CC0
> in a delay slot? I think that is the real root of the problem -- I
> do not think that should be happening.
> I suspect there's something funny going on in the c4x backend which
> is leading to this problem. The conditional branch should
> (effectively) use the cc0 reg, which should in turn prevent an insn
> which sets the cc0 reg from being placed in its delay slot. Right?
The c4x doesn't use cc0, it uses a hard register for CC.
I think the problem this patch fixes is not exposed by other targets
which only have a single delay slot.
Michael.