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Is const_int zero extended or sign-extended?

From: "Bingfeng Mei" <bmei at broadcom dot com>
To: "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>
Date: Thu, 12 Mar 2009 10:24:36 -0700
Subject: Is const_int zero extended or sign-extended?

Hello,
I am confused by one very basic concept :).  In the following rtx expression, if const_int is 32-bit and DImode is 64-bit, will the const_int sign-extended or zero-extended. In other word, is the content of reg:DI 95 0xffffffffffffffff9 or 0xffffffff9 after this instruction? 

(set:DI (reg:DI 95)
        (const_int -7 [0xfffffff9]))

Thanks,
Bingfeng Mei

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- Re: Is const_int zero extended or sign-extended?
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