cirrus75 <cirru...@uol.com.br> writes: > I am trying to improve combine pass (for all backends). One approach is > changing the order of some insns before combine pass starts. The first > problem I have is about the REGNOTES, they need to be rebuilt after changing > insn order. Does anyone know how to do that ?
It's not clear to me why changing insn order will help combine. Can you give us an example? In current mainline, the regnotes are added at the start of the combine pass by df_note_add_problem and df_analyze at the start of rest_of_handle_combine (please do not ask why it works this way). So if you reshuffle the insns in a pass before combine, and handle DF information appropriately, then you don't have to worry about the regnotes at all. Ian
