> 2013-03-25 Bin Cheng <bin.ch...@arm.com> > > * ifcvt.c (ifcvt_after_combine): New static variable. > (cheap_bb_rtx_cost_p): Set scale to REG_BR_PROB_BASE when optimizing > for size. > (rest_of_handle_if_conversion, rest_of_handle_if_after_combine): > Clear/set the variable ifcvt_after_combine.
The idea looks sensible. Some remarks: - add an after_combine parameter to if_convert and set the global from within this function instead of the pass functions (True, not TRUE, in the comment). - explain in the comment why you use optimize_function_for_speed_p instead of the 'speed' variable defined just above in cheap_bb_rtx_cost_p, - set the 'scale' variable only once in cheap_bb_rtx_cost_p (otherwise this is gratuitously confusing) and explain in the comment the reasoning for choosing REG_BR_PROB_BASE in the !speed case (I presume it's to void the identical scaling applied to the insns of the block). -- Eric Botcazou
