Re: [Qemu-devel] [PATCH 8/9] target-arm: A64: add support for 3 src data proc insns

[Richard Henderson]

On 12/09/2013 10:12 AM, Peter Maydell wrote:
> +    if (is_high) {
> +        /* SMULH and UMULH go via helpers for the 64x64->128 multiply */
> +        if (is_signed) {
> +            gen_helper_smulh(cpu_reg(s, rd), cpu_reg(s, rn), cpu_reg(s, rm));
> +        } else {
> +            gen_helper_umulh(cpu_reg(s, rd), cpu_reg(s, rn), cpu_reg(s, rm));
> +        }

Should use tcg_gen_mul[su]2_i64, with a dummy temp for the first arg; the
highpart result is placed into the second arg.



r~