[Mesa-dev] [PATCH] gallium: fixed modulo zero crashes in tgsi interpreter (v2)

[Roland Scheidegger]

Pushed, thanks!

Roland

Am 09.06.2017 um 15:39 schrieb Marius Gräfe:
> softpipe throws integer division by zero exceptions on windows
> when using % with integers in a geometry shader.
> 
> v2: Made error results consistent with existing div/mod zero handling in
>     tgsi. 64 bit signed integer division by zero returns zero like in
>     micro_idiv, unsigned returns ~0u like in micro_udiv.
>     Modulo operations always set all result bits to one (like in
>     micro_umod).
> ---
>  src/gallium/auxiliary/tgsi/tgsi_exec.c | 40 +++++++++++++++++-----------------
>  1 file changed, 20 insertions(+), 20 deletions(-)
> 
> diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
> index c41954c..97c75e9 100644
> --- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
> +++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
> @@ -846,40 +846,40 @@ static void
>  micro_u64div(union tgsi_double_channel *dst,
>               const union tgsi_double_channel *src)
>  {
> -   dst->u64[0] = src[0].u64[0] / src[1].u64[0];
> -   dst->u64[1] = src[0].u64[1] / src[1].u64[1];
> -   dst->u64[2] = src[0].u64[2] / src[1].u64[2];
> -   dst->u64[3] = src[0].u64[3] / src[1].u64[3];
> +   dst->u64[0] = src[1].u64[0] ? src[0].u64[0] / src[1].u64[0] : ~0ull;
> +   dst->u64[1] = src[1].u64[1] ? src[0].u64[1] / src[1].u64[1] : ~0ull;
> +   dst->u64[2] = src[1].u64[2] ? src[0].u64[2] / src[1].u64[2] : ~0ull;
> +   dst->u64[3] = src[1].u64[3] ? src[0].u64[3] / src[1].u64[3] : ~0ull;
>  }
>  
>  static void
>  micro_i64div(union tgsi_double_channel *dst,
>               const union tgsi_double_channel *src)
>  {
> -   dst->i64[0] = src[0].i64[0] / src[1].i64[0];
> -   dst->i64[1] = src[0].i64[1] / src[1].i64[1];
> -   dst->i64[2] = src[0].i64[2] / src[1].i64[2];
> -   dst->i64[3] = src[0].i64[3] / src[1].i64[3];
> +   dst->i64[0] = src[1].i64[0] ? src[0].i64[0] / src[1].i64[0] : 0;
> +   dst->i64[1] = src[1].i64[1] ? src[0].i64[1] / src[1].i64[1] : 0;
> +   dst->i64[2] = src[1].i64[2] ? src[0].i64[2] / src[1].i64[2] : 0;
> +   dst->i64[3] = src[1].i64[3] ? src[0].i64[3] / src[1].i64[3] : 0;
>  }
>  
>  static void
>  micro_u64mod(union tgsi_double_channel *dst,
>               const union tgsi_double_channel *src)
>  {
> -   dst->u64[0] = src[0].u64[0] % src[1].u64[0];
> -   dst->u64[1] = src[0].u64[1] % src[1].u64[1];
> -   dst->u64[2] = src[0].u64[2] % src[1].u64[2];
> -   dst->u64[3] = src[0].u64[3] % src[1].u64[3];
> +   dst->u64[0] = src[1].u64[0] ? src[0].u64[0] % src[1].u64[0] : ~0ull;
> +   dst->u64[1] = src[1].u64[1] ? src[0].u64[1] % src[1].u64[1] : ~0ull;
> +   dst->u64[2] = src[1].u64[2] ? src[0].u64[2] % src[1].u64[2] : ~0ull;
> +   dst->u64[3] = src[1].u64[3] ? src[0].u64[3] % src[1].u64[3] : ~0ull;
>  }
>  
>  static void
>  micro_i64mod(union tgsi_double_channel *dst,
>               const union tgsi_double_channel *src)
>  {
> -   dst->i64[0] = src[0].i64[0] % src[1].i64[0];
> -   dst->i64[1] = src[0].i64[1] % src[1].i64[1];
> -   dst->i64[2] = src[0].i64[2] % src[1].i64[2];
> -   dst->i64[3] = src[0].i64[3] % src[1].i64[3];
> +   dst->i64[0] = src[1].i64[0] ? src[0].i64[0] % src[1].i64[0] : ~0ll;
> +   dst->i64[1] = src[1].i64[1] ? src[0].i64[1] % src[1].i64[1] : ~0ll;
> +   dst->i64[2] = src[1].i64[2] ? src[0].i64[2] % src[1].i64[2] : ~0ll;
> +   dst->i64[3] = src[1].i64[3] ? src[0].i64[3] % src[1].i64[3] : ~0ll;
>  }
>  
>  static void
> @@ -4653,10 +4653,10 @@ micro_mod(union tgsi_exec_channel *dst,
>            const union tgsi_exec_channel *src0,
>            const union tgsi_exec_channel *src1)
>  {
> -   dst->i[0] = src0->i[0] % src1->i[0];
> -   dst->i[1] = src0->i[1] % src1->i[1];
> -   dst->i[2] = src0->i[2] % src1->i[2];
> -   dst->i[3] = src0->i[3] % src1->i[3];
> +   dst->i[0] = src1->i[0] ? src0->i[0] % src1->i[0] : ~0;
> +   dst->i[1] = src1->i[1] ? src0->i[1] % src1->i[1] : ~0;
> +   dst->i[2] = src1->i[2] ? src0->i[2] % src1->i[2] : ~0;
> +   dst->i[3] = src1->i[3] ? src0->i[3] % src1->i[3] : ~0;
>  }
>  
>  static void
>