On Tue, 2020-09-15 at 10:49 +0930, Alan Modra via Gcc-patches wrote:
> The existing "case AND" in this function is not sufficient for
> optabs.c:avoid_expensive_constant usage, where the AND is passed in
> outer_code.
>
> * config/rs6000/rs6000.c (rs6000_rtx_costs): Move costing for
> AND to CONST_INT case.
>
> diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> index 32044d33977..523d029800a 100644
> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -21150,16 +21150,13 @@ rs6000_rtx_costs (rtx x, machine_mode mode,
> int outer_code,
> || outer_code == MINUS)
> && (satisfies_constraint_I (x)
> || satisfies_constraint_L (x)))
> - || (outer_code == AND
> - && (satisfies_constraint_K (x)
> - || (mode == SImode
> - ? satisfies_constraint_L (x)
> - : satisfies_constraint_J (x))))
> - || ((outer_code == IOR || outer_code == XOR)
> + || ((outer_code == AND || outer_code == IOR || outer_code ==
> XOR)
> && (satisfies_constraint_K (x)
> || (mode == SImode
> ? satisfies_constraint_L (x)
> : satisfies_constraint_J (x))))
> + || (outer_code == AND
> + && rs6000_is_valid_and_mask (x, mode))
> || outer_code == ASHIFT
> || outer_code == ASHIFTRT
> || outer_code == LSHIFTRT
> @@ -21196,7 +21193,9 @@ rs6000_rtx_costs (rtx x, machine_mode mode,
> int outer_code,
> || outer_code == IOR
> || outer_code == XOR)
> && (INTVAL (x)
> - & ~ (unsigned HOST_WIDE_INT) 0xffffffff) == 0))
> + & ~ (unsigned HOST_WIDE_INT) 0xffffffff) == 0)
> + || (outer_code == AND
> + && rs6000_is_valid_2insn_and (x, mode)))
> {
> *total = COSTS_N_INSNS (1);
> return true;
> @@ -21334,26 +21333,6 @@ rs6000_rtx_costs (rtx x, machine_mode mode,
> int outer_code,
> *total += COSTS_N_INSNS (1);
> return true;
> }
> -
> - /* rotate-and-mask (no rotate), andi., andis.: 1 insn. */
> - HOST_WIDE_INT val = INTVAL (XEXP (x, 1));
> - if (rs6000_is_valid_and_mask (XEXP (x, 1), mode)
> - || (val & 0xffff) == val
> - || (val & 0xffff0000) == val
> - || ((val & 0xffff) == 0 && mode == SImode))
> - {
> - *total = rtx_cost (left, mode, AND, 0, speed);
> - *total += COSTS_N_INSNS (1);
> - return true;
> - }
> -
> - /* 2 insns. */
> - if (rs6000_is_valid_2insn_and (XEXP (x, 1), mode))
> - {
> - *total = rtx_cost (left, mode, AND, 0, speed);
> - *total += COSTS_N_INSNS (2);
> - return true;
> - }
> }
It's not exactly 1x1.. I tentatively conclude that the /* rotate-and-
mask */ lump of code here does go dead with the "case AND" changes
above.
thanks
-Will
>
> *total = COSTS_N_INSNS (1);
