> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc > index fb93a6fdd0a..be5e27fc391 100644 > --- a/gcc/config/i386/i386.cc > +++ b/gcc/config/i386/i386.cc > @@ -20600,12 +20600,26 @@ ix86_class_likely_spilled_p (reg_class_t rclass) > return false; > } > > -/* Implement TARGET_IRA_CALLEE_SAVED_REGISTER_COST_SCALE. */ > +/* Implement TARGET_CALLEE_SAVE_COST. */ > > static int > -ix86_ira_callee_saved_register_cost_scale (int) > -{ > - return 1; > +ix86_callee_save_cost (spill_cost_type, unsigned int hard_regno, > machine_mode, > + unsigned int, int mem_cost, const HARD_REG_SET &, bool) > +{ > + /* Account for the fact that push and pop are shorter and do their > + own allocation and deallocation. */ > + if (GENERAL_REGNO_P (hard_regno)) > + { > + /* push is 1 byte while typical spill is 4-5 bytes. > + ??? We probably should adjust size costs accordingly. > + Costs are relative to reg-reg move that has 2 bytes for 32bit > + and 3 bytes otherwise. Be sure that no cost table sets cost > + to 2, so we end up with 0. */ > + if (mem_cost <= 2 || optimize_function_for_size_p (cfun)) > + return 1; > + return mem_cost - 2; > + } > + return mem_cost;
This is OK. In general, I think we could also go with assert on mem_cost <= 2, since that is kind of bogus setting (I don't think we will ever need to support x86 CPU with memory stores being as cheap as reg-reg moves), but current form is good. Honza