splitting load immediates using high and lo_sum

[Dale Johannesen]

On Jul 21, 2005, at 5:04 PM, Tabony, Charles wrote:

>> From: Dale Johannesen [mailto:dalej@apple.com]
>>
>> On Jul 21, 2005, at 4:36 PM, Tabony, Charles wrote:
>>
>>> Hi,
>>>
>>> I am working on a port for a processor that has 32 bit registers but
>>> can
>>> only load 16 bit immediates.
>>>   ""
>>>   "%0.h = #HI(%1)")
>>
>> What are the semantics of this?  Low bits zeroed, or untouched?
>> If the former, your semantics are identical to Sparc; look at that.
>
> The low bits are untouched.  However, I would expect the compiler to
> always follow setting the high bits with setting the low bits.

OK, if you're willing to accept that limitation (your architecture could
handle putting the LO first, which Sparc can't) then Sparc is still a
good model to look at.  What it does should work for you.