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Re: [PATCH] PR63404, gcc 5 miscompiles linux block layer
- From: Richard Henderson <rth at redhat dot com>
- To: Jiong Wang <jiong dot wang at arm dot com>, Jeff Law <law at redhat dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Fri, 10 Oct 2014 10:45:02 -0700
- Subject: Re: [PATCH] PR63404, gcc 5 miscompiles linux block layer
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On 10/10/2014 09:52 AM, Richard Henderson wrote:
> I wonder what kind of fallout there would be from changing LO_SUM to
> RTX_BIN_ARITH, which is what it should have been all along.
The answer is "a lot". Mostly throughout simplify-rtx.c, wherein we'd have to
move all sorts of code around to accommodate the class change.
I've abandoned that line and I'm just testing a one line change to
shrink-wrap.c to accept LO_SUM.