On Tue, Apr 18, 2017 at 12:44 PM, Bin Cheng <bin.ch...@arm.com> wrote: > Hi, > This patch handles more cheap cases in function force_expr_to_var_cost, > specifically, > TRUNC_DIV_EXPR, BIT_AND_EXPR, BIT_IOR_EXPR, RSHIFT_EXPR and BIT_NOT_EXPR. > > Is it OK?
I wonder if using add_cost is good here. TRUNC_DIV by power of two better matches shift_cost, no, or div_pow2_cheap? Likewise for LSHIFT/RSHIFT. We do have [us]div_cost as well btw. And we have neg_cost. I mean if we're going all the way of using target based costs in force_expr_to_var_cost rather than estimate_num_insns then we should do as good as we can? Richard. > Thanks, > bin > 2017-04-11 Bin Cheng <bin.ch...@arm.com> > > * tree-ssa-loop-ivopts.c (force_expr_to_var_cost): Handle more > operators: TRUNC_DIV_EXPR, BIT_AND_EXPR, BIT_IOR_EXPR, RSHIFT_EXPR > and BIT_NOT_EXPR.
