Re: [PATCH 3/3] media: atomisp: Use max() macros
From: Hans Verkuil
Date: Fri Sep 27 2024 - 06:00:39 EST
On 27/09/2024 11:42, Ricardo Ribalda wrote:
> The max() macro produce nicer code and also fixes the following cocci
> errors:
>
> drivers/staging/media/atomisp/pci/sh_css_frac.h:40:17-18: WARNING opportunity for max()
> drivers/staging/media/atomisp/pci/sh_css_frac.h:50:17-18: WARNING opportunity for max()
>
> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> ---
> drivers/staging/media/atomisp/pci/sh_css_frac.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/media/atomisp/pci/sh_css_frac.h b/drivers/staging/media/atomisp/pci/sh_css_frac.h
> index 8ba65161f7a9..9642506d2388 100644
> --- a/drivers/staging/media/atomisp/pci/sh_css_frac.h
> +++ b/drivers/staging/media/atomisp/pci/sh_css_frac.h
> @@ -37,7 +37,7 @@ static inline int sDIGIT_FITTING(int v, int a, int b)
> int fit_shift = sFRACTION_BITS_FITTING(a) - b;
>
> v >>= sSHIFT;
> - v >>= fit_shift > 0 ? fit_shift : 0;
> + v >>= max(fit_shift, 0);
Does the warning go away if you change this to:
if (fit_shift > 0)
v >>= fit_shift;
Using 'max' for a shift is a bit weird in my opinion.
Also this change was done to reduce the min/max calls, so introducing
a new max call feels odd (although it should be fine).
Note that I think those cocci warnings should perhaps be ignored or
dropped. In part because of the huge macro expansion of min and max, but
also I often find the code that is not using min or max at least as readable,
if not more.
Regards,
Hans
>
> return clamp_t(int, v, sISP_VAL_MIN, sISP_VAL_MAX);
> }
> @@ -47,7 +47,7 @@ static inline unsigned int uDIGIT_FITTING(unsigned int v, int a, int b)
> int fit_shift = uFRACTION_BITS_FITTING(a) - b;
>
> v >>= uSHIFT;
> - v >>= fit_shift > 0 ? fit_shift : 0;
> + v >>= max(fit_shift, 0);
>
> return clamp_t(unsigned int, v, uISP_VAL_MIN, uISP_VAL_MAX);
> }
>