Re: [PATCH 6/8] qemu/bswap: Add const_le64()

[Philippe Mathieu-Daudé]

On 11/1/23 15:24, Jonathan Cameron via wrote:
> From: Ira Weiny <ira.weiny@intel.com>
>
> Gcc requires constant versions of cpu_to_le* calls.
>
> Add a 64 bit version.
>
> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>   include/qemu/bswap.h | 10 ++++++++++
>   1 file changed, 10 insertions(+)
>
> diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h
> index 346d05f2aa..e1eca22f25 100644
> --- a/include/qemu/bswap.h
> +++ b/include/qemu/bswap.h
> @@ -187,6 +187,15 @@ CPU_CONVERT(le, 64, uint64_t)
>    * used to initialize static variables.
>    */
>   #if HOST_BIG_ENDIAN
> +# define const_le64(_x)                          \
> +    ((((_x) & 0x00000000000000ffU) << 56) |      \
> +     (((_x) & 0x000000000000ff00U) << 40) |      \
> +     (((_x) & 0x0000000000ff0000U) << 24) |      \
> +     (((_x) & 0x00000000ff000000U) <<  8) |      \
> +     (((_x) & 0x000000ff00000000U) >>  8) |      \
> +     (((_x) & 0x0000ff0000000000U) >> 24) |      \
> +     (((_x) & 0x00ff000000000000U) >> 40) |      \
> +     (((_x) & 0xff00000000000000U) >> 56))

So looking back at 
https://lore.kernel.org/qemu-devel/20200917163106.49351-4-philmd@redhat.com/
this patch missed to update the function description:

 /*
- * Same as cpu_to_{be,le}{16,32} described below, except that gcc will
+ * Same as cpu_to_{be,le}{16,32,64} described below, except that gcc will
  * figure the result is a compile-time constant if you pass in a constant.
  * So this can be used to initialize static variables.
  */