[Beignet] [PATCH] GBE: don't split instruction for some special case.

[Zhigang Gong]

Ping for review comments.

On Fri, Nov 07, 2014 at 09:54:18AM +0800, Zhigang Gong wrote:
> If the src and dst are the same byte vector or the src
> is scalar, we don't need to split the instruction.
> 
> Thus the following instructions:
> (     269)  (-f1) sel(8)    g95<2>:B        g100<16,8,2>:B  0W              { align1 WE_normal 1Q };
> (     271)  (-f1) sel(8)    g95.16<2>:B     g100.16<16,8,2>:B 0W            { align1 WE_normal 2Q };
> 
> could be optimized to one sind16 instruction:
> (     263)  (-f1) sel(16)   g95<2>:B        g100<16,8,2>:B  0W              { align1 WE_normal 1H };
> 
> Signed-off-by: Zhigang Gong <zhigang.gong at intel.com>
> ---
>  backend/src/backend/gen_encoder.cpp | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/backend/src/backend/gen_encoder.cpp b/backend/src/backend/gen_encoder.cpp
> index 51e999e..094c894 100644
> --- a/backend/src/backend/gen_encoder.cpp
> +++ b/backend/src/backend/gen_encoder.cpp
> @@ -69,6 +69,10 @@ namespace gbe
>  
>    INLINE bool needToSplitAlu1(GenEncoder *p, GenRegister dst, GenRegister src) {
>      if (p->curr.execWidth != 16 || src.hstride == GEN_HORIZONTAL_STRIDE_0) return false;
> +    if (isVectorOfBytes(dst) == true &&
> +        ((isVectorOfBytes(src) == true && src.hstride == dst.hstride)
> +          || src.hstride == GEN_HORIZONTAL_STRIDE_0))
> +      return false;
>      if (isVectorOfBytes(dst) == true) return true;
>      if (isVectorOfBytes(src) == true) return true;
>      return false;
> @@ -79,7 +83,13 @@ namespace gbe
>           (src0.hstride == GEN_HORIZONTAL_STRIDE_0 &&
>            src1.hstride == GEN_HORIZONTAL_STRIDE_0))
>        return false;
> -    if (isVectorOfBytes(dst) == true) return true;
> +    if (isVectorOfBytes(dst) == true &&
> +        ((isVectorOfBytes(src0) == true && src0.hstride == dst.hstride) ||
> +          src0.hstride == GEN_HORIZONTAL_STRIDE_0) &&
> +        ((isVectorOfBytes(src1) == true && src1.hstride == dst.hstride) ||
> +          src1.hstride == GEN_HORIZONTAL_STRIDE_0))
> +      return false;
> +    if (isVectorOfBytes(dst) == true ) return true;
>      if (isVectorOfBytes(src0) == true) return true;
>      if (isVectorOfBytes(src1) == true) return true;
>      return false;
> -- 
> 1.8.3.2
> 
> _______________________________________________
> Beignet mailing list
> Beignet at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/beignet