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Re: help about new porting (.h file)


Hi Gabriele,

Gabriele Caracausi wrote:
Hi all,
* POINTER_SIZE is setted to 16 bit
* Pmode is setted to HImode
* INT_TYPE_SIZE is setted to 16 bit so HImode should be 8 bit.

No, HImode is 16 bits for the IP2k.


In MODES_TIEBLE_P is written that QImode and HImode are readable as the same type and this should mean that they have both the same size, but if HImode is 16 bit wide QImode should be 8 bit wide and so they should not

When the modes are tieable it means that we can avoid copying things around. I just reviewed this code though and the current definition for the IP2k is just plain wrong (as was the predecessor to it). The code suffers some minor size regressions if I just define it to be "1" but also wins in a number of other places.


In this particular port the key thing is to avoid gcc thinking that it can tie certain HImode or QImode regs to SImode or DImode because the 16-bit IP and DP pointer regs are not contiguous with the 32 8-bit GPRs.


Regards, Dave



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