Re: drm/amd/display: Restructuring and cleaning up DML

[Dave Jones <davej@codemonkey.org.uk>]

On Sat, Nov 18, 2017 at 12:02:01AM +0000, Linux Kernel wrote:
 > Web:        https://git.kernel.org/torvalds/c/6d04ee9dc10149db842d41de66eca201c9d91b60
 > Commit:     6d04ee9dc10149db842d41de66eca201c9d91b60
 > Parent:     19b7fe4a48efbe0f7e8c496b040c4eb16ff02313
 > Refname:    refs/heads/master
 > Author:     Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
 > AuthorDate: Wed Aug 23 16:43:17 2017 -0400
 > Committer:  Alex Deucher <alexander.deucher@amd.com>
 > CommitDate: Sat Oct 21 16:45:24 2017 -0400
 > 
 >     drm/amd/display: Restructuring and cleaning up DML
 >     
 >     Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
 >     Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
 >     Acked-by: Harry Wentland <Harry.Wentland@amd.com>
 >     Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
 > ---


 > diff --git a/drivers/gpu/drm/amd/display/dc/calcs/dcn_calc_math.c b/drivers/gpu/drm/amd/display/dc/calcs/dcn_calc_math.c
 > index a18474437990..b6abe0f3bb15 100644
 > --- a/drivers/gpu/drm/amd/display/dc/calcs/dcn_calc_math.c
 > +++ b/drivers/gpu/drm/amd/display/dc/calcs/dcn_calc_math.c
 > @@ -27,20 +27,36 @@
 >  
 >  float dcn_bw_mod(const float arg1, const float arg2)
 >  {
 > +	if (arg1 != arg1)
 > +		return arg2;
 > +	if (arg2 != arg2)
 > +		return arg1;
 >  	return arg1 - arg1 * ((int) (arg1 / arg2));
 >  }
 >  
 >  float dcn_bw_min2(const float arg1, const float arg2)
 >  {
 > +	if (arg1 != arg1)
 > +		return arg2;
 > +	if (arg2 != arg2)
 > +		return arg1;
 >  	return arg1 < arg2 ? arg1 : arg2;
 >  }
 >  
 >  unsigned int dcn_bw_max(const unsigned int arg1, const unsigned int arg2)
 >  {
 > +	if (arg1 != arg1)
 > +		return arg2;
 > +	if (arg2 != arg2)
 > +		return arg1;
 >  	return arg1 > arg2 ? arg1 : arg2;
 >  }
 >  float dcn_bw_max2(const float arg1, const float arg2)
 >  {
 > +	if (arg1 != arg1)
 > +		return arg2;
 > +	if (arg2 != arg2)
 > +		return arg1;
 >  	return arg1 > arg2 ? arg1 : arg2;
 >  }

This looks really, really bizarre. What was the intention here ?

(This, and a bunch of other stuff in this driver picked up by Coverity,
 sign up at scan.coverity.com if you want access, and I'll approve.)

	Dave