Calling Convention

Entry conventions are very conventional: the first N arguments in registers and the rest on the stack.

Return Convention

All returns are now direct; that is, a return is made by jumping to the code associated with the info table of the topmost stack frame.

GHC used to have a more complex return convention called vectored returns in which some stack frames pointed to vectors of return addresses; this was dropped in GHC 6.8 after measurements that showed it was not (any longer) worthwhile.