Re: [Qemu-devel] [PATCH v3 15/50] tcg: add MO_HADDR to TCGMemOp

[Richard Henderson]

On 6/14/19 10:11 AM, Alex Bennée wrote:
> +    /*
> +     * SoftMMU-only: if set, the TCG backend puts the corresponding host 
> address
> +     * in CPUArchState.hostaddr.
> +     */
> +    MO_HSHIFT = MO_ASHIFT + 3,
> +    MO_HADDR = 1 << MO_HSHIFT,

FYI, Alex and I talked about recomputing the host address within the helper.

For at least a few of the hosts, we currently never compute the full host
address into a single register -- we use reg+reg addressing when possible.
It's only a couple of instructions to re-compute, given that we know that the
tlb lookup succeeded, and importantly they are all out of line and not bloating
the inline code further.


r~