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problem with subregs.


Hi,

My team is working on a new port and we are trying a long time to solve a
problem, I was wondering whether other
architectures deal with it or if there's a solution for this problem we
haven't thought of.
In our architecture there are some short registers (HImode) and some long
ones (SImode).
The compiler can use a pair of HI regs to get a long one but if it uses a
long reg then it cannot refer to it's
upper word.
Still, the compiler turns  (subreg:HI (reg SI 67) 2)   -> refers to the
upper word of reg 67.
                                      to    (reg:HI 13 r13)
-> r13 is long reg.

And this is wrong since the second rtl generates code that refers to the
lower word. Can anyone advice?

Regards,

   Tal Agmon
   National Semiconductor.






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