On 2024/10/17 03:31, Richard Henderson wrote:
> Use vrsub.vi to subtract from a constant.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> tcg/riscv/tcg-target-con-set.h | 1 +
> tcg/riscv/tcg-target.c.inc | 8 ++++++--
> 2 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/tcg/riscv/tcg-target-con-set.h b/tcg/riscv/tcg-target-con-set.h
> index 97e6ecdb0f..d8ce5414f5 100644
> --- a/tcg/riscv/tcg-target-con-set.h
> +++ b/tcg/riscv/tcg-target-con-set.h
> @@ -25,6 +25,7 @@ C_O0_I2(v, r)
> C_O1_I1(v, r)
> C_O1_I1(v, v)
> C_O1_I2(v, v, v)
> +C_O1_I2(v, vK, v)
> C_O1_I2(v, v, vK)
> C_O1_I2(v, v, vL)
> C_O1_I4(v, v, vL, vK, vK)
> diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc
> index ce8d6d0293..1ce2f291d3 100644
> --- a/tcg/riscv/tcg-target.c.inc
> +++ b/tcg/riscv/tcg-target.c.inc
> @@ -2350,7 +2350,11 @@ static void tcg_out_vec_op(TCGContext *s, TCGOpcode opc,
> break;
> case INDEX_op_sub_vec:
> set_vtype_len_sew(s, type, vece);
> - tcg_out_opc_vv(s, OPC_VSUB_VV, a0, a1, a2);
> + if (const_args[1]) {
> + tcg_out_opc_vi(s, OPC_VRSUB_VI, a0, a2, a1);
> + } else {
> + tcg_out_opc_vv(s, OPC_VSUB_VV, a0, a1, a2);
> + }
> break;
> case INDEX_op_and_vec:
> set_vtype_len(s, type);
> @@ -2565,7 +2569,7 @@ static TCGConstraintSetIndex tcg_target_op_def(TCGOpcode op)
> case INDEX_op_xor_vec:
> return C_O1_I2(v, v, vK);
> case INDEX_op_sub_vec:
> - return C_O1_I2(v, v, v);
> + return C_O1_I2(v, vK, v);
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Zhiwei
> case INDEX_op_cmp_vec:
> return C_O1_I2(v, v, vL);
> case INDEX_op_cmpsel_vec: