ping
> -----Original Message-----
> From: Wilco Dijkstra [mailto:wilco.dijks...@arm.com]
> Sent: 13 November 2015 16:03
> To: 'gcc-patches@gcc.gnu.org'
> Subject: [PATCH 3/4][AArch64] Add CCMP to rtx costs
>
> This patch adds support for rtx costing of CCMP. The cost is the same as
> int/FP compare, however comparisons with zero get a slightly
> larger cost. This means we prefer emitting compares with zero so they can be
> merged with ALU operations.
>
> OK for commit?
>
> ChangeLog:
> 2015-11-13 Wilco Dijkstra <wdijk...@arm.com>
>
> * gcc/config/aarch64/aarch64.c (aarch64_if_then_else_costs):
> Add support for CCMP costing.
>
> ---
> gcc/config/aarch64/aarch64.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
> index a224982..b789841 100644
> --- a/gcc/config/aarch64/aarch64.c
> +++ b/gcc/config/aarch64/aarch64.c
> @@ -5638,6 +5638,26 @@ aarch64_if_then_else_costs (rtx op0, rtx op1, rtx op2,
> int *cost, bool speed)
> }
> else if (GET_MODE_CLASS (GET_MODE (inner)) == MODE_CC)
> {
> + /* CCMP. */
> + if ((GET_CODE (op1) == COMPARE) && CONST_INT_P (op2))
> + {
> + /* Increase cost of CCMP reg, 0, imm, CC to prefer CMP reg, 0. */
> + if (XEXP (op1, 1) == const0_rtx)
> + *cost += 1;
> + if (speed)
> + {
> + machine_mode mode = GET_MODE (XEXP (op1, 0));
> + const struct cpu_cost_table *extra_cost
> + = aarch64_tune_params.insn_extra_cost;
> +
> + if (GET_MODE_CLASS (mode) == MODE_INT)
> + *cost += extra_cost->alu.arith;
> + else
> + *cost += extra_cost->fp[mode == DFmode].compare;
> + }
> + return true;
> + }
> +
> /* It's a conditional operation based on the status flags,
> so it must be some flavor of CSEL. */
>
> --
> 1.9.1
