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Re: PATCH [1/n] addr32: Properly use Pmode and word_mode


On Mon, Mar 5, 2012 at 9:20 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Mon, Mar 05, 2012 at 09:13:49AM -0800, H.J. Lu wrote:
>> >> We are expecting address to be 0x1001 - 1 == 0x1000. ?But, what we get
>> >> is 0x1000 + 0xffffffff, not 0x1000 since 0x67 address prefix only applies to
>> >> base register to zero-extend 0xffffffff to 64bit.
>> >
>> > I would call this a bug in the specification - I guess that
>> > 0x1001(%eax) works correctly.
>>
>> This is how hardware works.
>
> Do you really need to use addr32 prefixes for the direct TLS seg refs?
> Without that the addresses will be sign-extended from the 32-bit immediate
> (which is used in LP64 x86_64 code too) and everything will work fine, won't
> it?
>

32bit immediate is OK.  The problem is fs:(32bit register).


-- 
H.J.


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