Setting ARM PIC register (Was: RE: GCC 4.5.0 Status Report (2009-05-05))

[Mark Mitchell]

Richard Earnshaw wrote:

>>>> The easiest solution would be to just make a note that you need the  
>>>> PIC register and then, when expanding the prologue emit the  
>>>> necessary instructions.  IMO that makes sense as PIC register setup  
>>>> usually is something the prologue does, like all the other register  
>>>> setups necessary.

>> How about emitting a set at each place the PIC register is needed,
>> and making sure that gcse will will common these sets where
>> appropriate?

> I'd rather not.  -O0 code is bad enough already; and this just makes
> more work for the compiler.

I agree.

What was the underlying fundamental change here that made the ARM
strategy stop working?

-- 
Mark Mitchell
CodeSourcery
mark@codesourcery.com
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