[LLVMdev] i128 backend or frontend lowering

[Andrew Lenharth]

I am seeing i128 from llvm-gcc on Alpha.  I know the calling
convention for them, they are split into two registers, but I don't
know if that should be handled in the frontend or the backend.  I
would just as soon do it in the backend, but I didn't see any support
in the new calling convention work for automatically splitting an
argument into multiple registers.

Is the backend the best place to do this or should I attempt to make
llvm-gcc not generate i128 in the first place?

e.g. I need to convert foo(i128) -> foo(i64 (low bits), i64 (high bits))

Andrew