Aurelien Buhrig <aurelien.buhrig.gcc@xxxxxxxxx> writes: > When is it safe to generate a FAIL in the define_expand of a mov pattern? > Is it enough to test !can_create_pseudo_p() before a FAIL ? > > If no such test is performed, some mov insns can be omitted (ex: > expand_call/store_one_arg), without any error message or warning and > it can be difficult to debug it. > Is it a desirable behavior? In general, a mov pattern may not FAIL. The reload pass relies on the ability to generate moves even when no pseudo-registers are available. It's true that the middle-end does not use assertions to enforce this. Ian
