Hi!
On Thu, Oct 08, 2020 at 09:27:57AM +1030, Alan Modra wrote:
> * config/rs6000/rs6000.c (rotate_insert_cost): New function.
> (rs6000_rtx_costs): Cost IOR.
>
> diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> index 383d2901c9f..15a806fe307 100644
> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -21206,6 +21206,91 @@ rs6000_cannot_copy_insn_p (rtx_insn *insn)
> && get_attr_cannot_copy (insn);
> }
>
> +/* Handle rtx_costs for scalar integer rotate and insert insns. */
You need to document here what the return value means, and what the
preconditions for "left" (and "right") are.
> +static bool
> +rotate_insert_cost (rtx left, rtx right, machine_mode mode, bool speed,
> + int *total)
> +{
> + if (GET_CODE (right) == AND
... because you never check the CODE of "left".
> + && CONST_INT_P (XEXP (right, 1))
> + && UINTVAL (XEXP (left, 1)) + UINTVAL (XEXP (right, 1)) + 1 == 0)
HOST_WIDE_INT is always exactly 64 bits now, so you could do "== -1".
> + {
> + rtx leftop = XEXP (left, 0);
> + rtx rightop = XEXP (right, 0);
> +
> + /* rotlsi3_insert_5. */
> + if (REG_P (leftop)
> + && REG_P (rightop)
> + && mode == SImode
> + && UINTVAL (XEXP (left, 1)) != 0
> + && UINTVAL (XEXP (right, 1)) != 0
> + && rs6000_is_valid_mask (XEXP (left, 1), NULL, NULL, mode))
> + return true;
Empty line after return please.
> + /* rotldi3_insert_6. */
> + if (REG_P (leftop)
> + && REG_P (rightop)
> + && mode == DImode
> + && exact_log2 (-UINTVAL (XEXP (left, 1))) > 0)
> + return true;
> + /* rotldi3_insert_7. */
> + if (REG_P (leftop)
> + && REG_P (rightop)
> + && mode == DImode
> + && exact_log2 (-UINTVAL (XEXP (right, 1))) > 0)
> + return true;
Those could just use rs6000_is_valid_mask as well?
> + rtx mask = 0;
> + rtx shift = leftop;
> + rtx_code shift_code = GET_CODE (shift);
> + /* rotl<mode>3_insert. */
> + if (shift_code == ROTATE
> + || shift_code == ASHIFT
> + || shift_code == LSHIFTRT)
> + mask = right;
> + else
> + {
> + shift = rightop;
> + shift_code = GET_CODE (shift);
> + /* rotl<mode>3_insert_2. */
> + if (shift_code == ROTATE
> + || shift_code == ASHIFT
> + || shift_code == LSHIFTRT)
> + mask = left;
> + }
> + if (mask
> + && CONST_INT_P (XEXP (shift, 1))
> + && rs6000_is_valid_insert_mask (XEXP (mask, 1), shift, mode))
> + {
> + *total += rtx_cost (XEXP (shift, 0), mode, shift_code, 0, speed);
> + *total += rtx_cost (XEXP (mask, 0), mode, AND, 0, speed);
> + return true;
> + }
> + }
> + /* rotl<mode>3_insert_3. */
> + if (GET_CODE (right) == ASHIFT
> + && CONST_INT_P (XEXP (right, 1))
> + && (INTVAL (XEXP (right, 1))
> + == exact_log2 (UINTVAL (XEXP (left, 1)) + 1)))
> + {
> + *total += rtx_cost (XEXP (left, 0), mode, AND, 0, speed);
> + *total += rtx_cost (XEXP (right, 0), mode, ASHIFT, 0, speed);
> + return true;
> + }
> + /* rotl<mode>3_insert_4. */
> + if (GET_CODE (right) == LSHIFTRT
> + && CONST_INT_P (XEXP (right, 1))
> + && mode == SImode
> + && (INTVAL (XEXP (right, 1))
> + + exact_log2 (-UINTVAL (XEXP (left, 1)))) == 32)
> + {
> + *total += rtx_cost (XEXP (left, 0), mode, AND, 0, speed);
> + *total += rtx_cost (XEXP (right, 0), mode, LSHIFTRT, 0, speed);
> + return true;
> + }
> + return false;
> +}
> +
> /* Compute a (partial) cost for rtx X. Return true if the complete
> cost has been computed, and false if subexpressions should be
> scanned. In either case, *TOTAL contains the cost result.
> @@ -21253,7 +21338,7 @@ static bool
> rs6000_rtx_costs (rtx x, machine_mode mode, int outer_code,
> int opno ATTRIBUTE_UNUSED, int *total, bool speed)
> {
> - rtx right;
> + rtx left, right;
> int code = GET_CODE (x);
>
> switch (code)
> @@ -21435,7 +21520,7 @@ rs6000_rtx_costs (rtx x, machine_mode mode, int
> outer_code,
> right = XEXP (x, 1);
> if (CONST_INT_P (right))
> {
> - rtx left = XEXP (x, 0);
> + left = XEXP (x, 0);
> rtx_code left_code = GET_CODE (left);
>
> /* rotate-and-mask: 1 insn. */
> @@ -21452,9 +21537,16 @@ rs6000_rtx_costs (rtx x, machine_mode mode, int
> outer_code,
> return false;
>
> case IOR:
> - /* FIXME */
> *total = COSTS_N_INSNS (1);
> - return true;
> + left = XEXP (x, 0);
> + if (GET_CODE (left) == AND
> + && CONST_INT_P (XEXP (left, 1)))
> + {
> + right = XEXP (x, 1);
> + if (rotate_insert_cost (left, right, mode, speed, total))
> + return true;
> + }
> + return false;
>
> case CLZ:
> case XOR:
Please wait this until stage 1. Sorry.
Segher
