> The problem I see is that for registers 100,101 I get best register > class D instead of R - actually they get the same cost and D is chosen > (maybe because it is first).
Hi Frank. Do D and R overlap? It would be useful to know which regs are in which class, before trying to understand what is going on. Can you paste an example of your define_insn from your MD file to show how operands from D or R are both valid? I ask this because it is possible to express that D is more expensive than R with operand constraints. For general IRA info, you might like to look over my long thread on here called "Understanding IRA". Cheers, Ian
