[PATCH] ARM: Homogeneous aggregates must be allocated to contiguous registers

[Oliver Stannard]

  I would prefer to think of this as a refactoring to move the existing logic for handling HAs into the backend. It looks like it would be possible to solve this by re-ordering the arguments, but any other frontend which wants to generate ABI-compliant code would have to implement the same process.

  > It also doubled the attribute size just for one (rare) and target-specific case...

  I'm not sure what you mean by this. If you are referring to ArgFlagsTy, I re-used the top two bits from the ByValSize field, so the size stays the same.

http://llvm-reviews.chandlerc.com/D3082