On Fri, Aug 17, 2007 at 06:02:06PM +0200, Rask Ingemann Lambertsen wrote: > What happened to the experiments you described at > <URL:http://gcc.gnu.org/ml/gcc/2004-06/msg01178.html>? Emitting a no-op move > of the (set (reg) (reg)) form won't work, but maybe something like > > (insn (use (reg) (expr_list:REG_EQUAL ...))) > > would work?
And if not, the required no-op move pattern could look like this: (define_insn "*no-op-move" [(set (match_operand 0 "register_operand") (match_dup 0))] "REG_P (operands[0]) && !reload_completed" { gcc_abort (); } Reload will delete such an insn even at -O0. -- Rask Ingemann Lambertsen Danish law requires addresses in e-mail to be logged and stored for a year