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Re: I want to rid ugly float load/stores used only for data movement



> MLR> What I want to do is modify gcc to stop generating code like that, but
> MLR> not shut down generating float instructions entirely, as in
> MLR> "soft_float".  

>       Your intent cannot be implemented safely in GCC.  If GCC knows it
> has FPRs and FPRs hold 64-bit values (which they must), it will use them
> for 64-bit moves.  Cannot be avoided safely.

It ought to be possible to severely discourage use of fp registers for non 
fp objects by arranging for MEMORY_MOVE_COST to return a large value when 
given an FP register class and a non-FP mode.

This won't eliminate the use of such registers but it should cut it down 
significantly if the compiler respects this correctly.

R.




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