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Re: PATCH: PR target/39590: inline asm %z on amd64 says "ll" instead of "q"


On Wed, Apr 22, 2009 at 6:45 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Wed, Apr 22, 2009 at 5:54 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
>> On Wed, Apr 22, 2009 at 2:28 PM, Jakub Jelinek <jakub@redhat.com> wrote:
>>
>>>> I think that we should move special fild/fist handling out of 'z' into
>>>> new 'Z' operand modifier. This simplifies code a lot, and enables all
>>>> sorts of special fild/fist handling to be handled in one place without
>>>> overloading (otherwise undocumented!) 'z' modifier too much.
>>>
>>> Wouldn't it be better to keep %zN as is and add %ZN which would expand
>>> to q instead of ll for 64-bit operand?
>>> When a new modifier is added, I don't see any advantages of modifying the
>>> behaviour of %zN.
>>
>> This is in fact the core of the problem. People are using %z, and this
>> modifier will generate "ll" suffix when DImode memory operand is
>> processed. We are changing %z to avoid this, so %z will always
>> generate "q", no matter if assembler supports fildq or not.
>>
>
> Do we need a testcase for "%z"?
>

We also need to document 'Z' in i386.md.

-- 
H.J.


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