[Libclc-dev] [PATCH 3/3] powr: Use denormal path only

[Aaron Watry via Libclc-dev]

These 3 look ok to me, and I just ran them through 1.2 CTS on my RX580
as well (passed).

I did notice that clicking through the patches on the mailing list
archive, the contents of the affected parts of these files are
identical. Maybe a possible thing we can de-duplicate at some point
once things are in better shape.

--Aaron

On Thu, 2018-04-12 at 14:53 -0400, Jan Vesely via Libclc-dev wrote:
> It's OK to either flush to 0 or return denormal result if the device
> does not support denormals. See sec 7.2 and 7.5.3 of OCL specs
> Fixes CTS on carrizo and turks.
> Signed-off-by: Jan Vesely <jan.vesely at rutgers.edu>
> ---
>  generic/lib/math/clc_powr.cl | 12 +-----------
>  1 file changed, 1 insertion(+), 11 deletions(-)
> 
> diff --git a/generic/lib/math/clc_powr.cl
> b/generic/lib/math/clc_powr.cl
> index 9074a8b..ef97d3c 100644
> --- a/generic/lib/math/clc_powr.cl
> +++ b/generic/lib/math/clc_powr.cl
> @@ -165,17 +165,7 @@ _CLC_DEF _CLC_OVERLOAD float __clc_powr(float x,
> float y)
>      tv = USE_TABLE(exp_tbl_ep, j);
>  
>      float expylogx = mad(tv.s0, poly, mad(tv.s1, poly, tv.s1)) +
> tv.s0;
> -    float sexpylogx;
> -    if (!__clc_fp32_subnormals_supported()) {
> -		int explg = ((as_uint(expylogx) & EXPBITS_SP32 >>
> 23) - 127);
> -		m = (23-(m + 149)) == 0 ? 1: m;
> -		uint mantissa =  ((as_uint(expylogx) &
> MANTBITS_SP32)|IMPBIT_SP32) >> (23-(m + 149));
> -		sexpylogx = as_float(mantissa);
> -    } else {
> -		sexpylogx = expylogx * as_float(0x1 << (m + 149));
> -    }
> -
> -
> +    float sexpylogx = expylogx * as_float(0x1 << (m + 149));
>      float texpylogx = as_float(as_int(expylogx) + m2);
>      expylogx = m < -125 ? sexpylogx : texpylogx;
>