On Thu, Jul 9, 2015 at 8:05 PM, H.J. Lu <hongjiu...@intel.com> wrote:
> We reduce code size for IA MCU by adjusting variable shift costs for IA
> MCU. OK for trunk?
IMO, tuning patches should fall into "obvious" category. I don't have
any data to to do any meaningful review of a cost metric for a new
target.
So, instead of rubberstamping them again and again, these kind of
patches are pre-approved for all non-algorithmic tuning changes for
IAMCU target.
Uros.
> Thanks.
>
>
> H.J.
> ---
> PR target/66821
> * config/i386/i386.c (iamcu_cost): Adjust variable shift costs.
> ---
> gcc/config/i386/i386.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index 85e59a8..e4e505c 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -420,7 +420,7 @@ static const
> struct processor_costs iamcu_cost = {
> COSTS_N_INSNS (1), /* cost of an add instruction */
> COSTS_N_INSNS (1) + 1, /* cost of a lea instruction */
> - COSTS_N_INSNS (4), /* variable shift costs */
> + COSTS_N_INSNS (1), /* variable shift costs */
> COSTS_N_INSNS (1), /* constant shift costs */
> {COSTS_N_INSNS (11), /* cost of starting multiply for QI */
> COSTS_N_INSNS (11), /* HI */
> --
> 2.4.3
>
