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Date: Fri, 29 Jul 2011 10:56:00 -0000
Message-ID: <CAGs3Rfth_Ds57WT8-Wg0=c3tFEvwkUE3Hg4nJ=kx-+fvxEtrvQ@mail.gmail.com>
Subject: Defining constraint for registers tuple
From: Kirill Yukhin <kirill.yukhin@gmail.com>
To: gcc@gcc.gnu.org
Cc: Kirill Yukhin <kirill.yukhin@gmail.com>
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Hi guys,
I'm working on implementation of `mulx` (which is part of BMI2). One
of improvements compared generic `mul` is that it allows to specify
destination registers.
For `mul` we have `A` constraint, which stands for AX:DX pair.
So, is there a possibility to relax such cinstraint and allow any pair
of registers as destination?

Thanks, K