Re: [Qemu-devel] [PATCH v2 01/13] target-arm: A64: add support for conditional select

[Peter Maydell]

On 6 December 2013 16:59, Richard Henderson <address@hidden> wrote:
> Sorry for missing this in the first round: For the silly corner case of Rd ==
> XZR, tcg_rd is dead after the branch.
>
> We could either move the tcg_rd assignment down into each basic block with the
> assignment to tcg_src, or simply add
>
>     if (rd == 31) {
>         /* silly no-op write; until we use movcond we must special-case
>            this to avoid a dead temporary across basic blocks.  */
>         return;
>     }
>
> Either solution is ok by me.

That specialcase looks simplest to me.

thanks
-- PMM