[llvm-commits] [llvm] r116348 - in /llvm/trunk: lib/Target/ARM/ARMInstrVFP.td test/MC/ARM/simple-fp-encoding.ll

[Bob Wilson]

On Oct 12, 2010, at 3:47 PM, Jim Grosbach wrote:

> Not really. It might make sense to put some of those bits on the same line, though, which would help (the portions that are encoding different pieces of the same operand, e.g.). Something like:
> 
>  bits<5> Dd;  bits<5> Dn;  bits<5> Dm;
>  let Inst{3-0} = Dm{3-0};  let Inst{5} = Dm{4};
>  let Inst{19-16} = Dn{3-0}; let Inst{7} = Dn{4};
>  let Inst{15-12} = Dd{3-0}; let Inst{22} = Dd{4};
> 
> We may also be able to later refactor some of this sort of thing to put lots of stuff in the base classes rather than the per-instruction patterns. That would help even more. I'm not sure our definitions are laid out in a way that makes that very easy, though (dunno that they're not, either).

Can we try to put it in the base classes?  It would be worth the effort to do some refactoring to make that possible.  I think it will be less work to do it that way from the start rather than doing it this way first and then refactoring it all later.