How do we access higher order bits of a register?

Ian Lance Taylor iant@google.com
Tue Nov 22 22:10:00 GMT 2011


Ayonam Ray <ayonam@gmail.com> writes:

> On 22 November 2011 20:30, Ian Lance Taylor <iant@google.com> wrote:
>> Ayonam Ray <ayonam@gmail.com> writes:
>>
>>> I wanted to write an RTL that would access the higher order bits of a
>>> register.  I saw that high:<mode> works only with constants or labels.
>>>  The subreg:<mode> only takes the lower order bits.  Can't find any
>>> way to address the higher order bits.  Any help would be appreciated.
>>
>> If it is a single hard register, use a shift.
>>
>> Ian
>>
>
> Thanks for your reply.
> It is indeed a single hard register.  But I need it as an lvalue.

Use zero_extract.

Ian



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