[Mesa-dev] [PATCH v2 01/23] mesa/format_utils: Fix a bug in unorm_to_float helper function

[Ian Romanick]

This patch is

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

Should it also be tagged for 10.4?

On 12/01/2014 03:04 AM, Iago Toral Quiroga wrote:
> From: Jason Ekstrand <jason.ekstrand at intel.com>
> 
> This patch fixes the return of a wrong value when x is lower than
> -MAX_INT(src_bits) as the result would not be between [-1.0 1.0].
> 
> v2 by Samuel Iglesias <siglesias at igalia.com>:
>     - Modify unorm_to_float() to avoid doing the division when
>       x == -MAX_INT(src_bits)
> ---
>  src/mesa/main/format_utils.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/mesa/main/format_utils.c b/src/mesa/main/format_utils.c
> index 93a0cea..5dd0848 100644
> --- a/src/mesa/main/format_utils.c
> +++ b/src/mesa/main/format_utils.c
> @@ -152,7 +152,7 @@ unorm_to_float(unsigned x, unsigned src_bits)
>  static inline float
>  snorm_to_float(int x, unsigned src_bits)
>  {
> -   if (x == -MAX_INT(src_bits))
> +   if (x <= -MAX_INT(src_bits))
>        return -1.0f;
>     else
>        return x * (1.0f / (float)MAX_INT(src_bits));
>