Re: [PATCH v2 17/54] tcg: Introduce tcg_out_xchg

[Philippe Mathieu-Daudé]

On 11/4/23 03:04, Richard Henderson wrote:
> We will want a backend interface for register swapping.
> This is only properly defined for x86; all others get a
> stub version that always indicates failure.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   tcg/tcg.c                        | 2 ++
>   tcg/aarch64/tcg-target.c.inc     | 5 +++++
>   tcg/arm/tcg-target.c.inc         | 5 +++++
>   tcg/i386/tcg-target.c.inc        | 8 ++++++++
>   tcg/loongarch64/tcg-target.c.inc | 5 +++++
>   tcg/mips/tcg-target.c.inc        | 5 +++++
>   tcg/ppc/tcg-target.c.inc         | 5 +++++
>   tcg/riscv/tcg-target.c.inc       | 5 +++++
>   tcg/s390x/tcg-target.c.inc       | 5 +++++
>   tcg/sparc64/tcg-target.c.inc     | 5 +++++
>   tcg/tci/tcg-target.c.inc         | 5 +++++
>   11 files changed, 55 insertions(+)
>
> diff --git a/tcg/tcg.c b/tcg/tcg.c
> index 328e018a80..fde5ccc57c 100644
> --- a/tcg/tcg.c
> +++ b/tcg/tcg.c
> @@ -115,6 +115,8 @@ static void tcg_out_exts_i32_i64(TCGContext *s, TCGReg ret, 
> TCGReg arg);
>   static void tcg_out_extu_i32_i64(TCGContext *s, TCGReg ret, TCGReg arg);
>   static void tcg_out_extrl_i64_i32(TCGContext *s, TCGReg ret, TCGReg arg);
>   static void tcg_out_addi_ptr(TCGContext *s, TCGReg, TCGReg, tcg_target_long);
> +static bool tcg_out_xchg(TCGContext *s, TCGType type, TCGReg r1, TCGReg r2)
> +    __attribute__((unused));

Can you document this in docs/devel/tcg-ops.rst?

Otherwise,

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>