On Fri, Mar 20, 2015 at 11:27 AM, Thomas Preud'homme wrote: > Sorry, I missed the parenthesis. REG_P needs indeed to be kept. I'd be > tempted to use !HARD_REGISTER_P instead since REG_P is already > checked but I don't mind either way.
I put the cprop_reg_p check there instead of !HARD_REGISTER_P because I like to be able to quickly find all places where a similar check is performed. The check is whether the reg is something that copy propagation can handle, and that is what I added cprop_reg_p for. (Note that cprop can _currently_ handle only pseudos but there is no reason why a limited set of hard regs can't be handled also, e.g. the flag registers like in targetm.fixed_condition_code_regs). In this case, the result is that REG_P is checked twice. But then again, cprop_reg_p will be inlined and the double check optimized away. Anyway, I guess we've bikeshedded long enough over this patch as it is :-) Let's post a final form and declare it OK for stage1. As for PSEUDO_REG_P: If it were up to me, I'd like to have in rtl.h: static bool hard_register_p (rtx x) { return (REG_P (x) && HARD_REGISTER_NUM_P (REGNO (x))); } static bool pseudo_register_p (rtx x) { return (REG_P (x) && !HARD_REGISTER_NUM_P (REGNO (x))); } and do away with all the FIRST_PSEUDO_REGISTER tests. But I've proposed this in the past and there was opposition. Perhaps when we introduce a rtx_reg class... Ciao! Steven