On Tue, Jun 24, 2014 at 1:32 AM, Abdiel Janulgue <abdiel.janul...@linux.intel.com> wrote: > Signed-off-by: Abdiel Janulgue <abdiel.janul...@linux.intel.com> > --- > src/glsl/opt_algebraic.cpp | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/src/glsl/opt_algebraic.cpp b/src/glsl/opt_algebraic.cpp > index 8d7609d..0d694b6 100644 > --- a/src/glsl/opt_algebraic.cpp > +++ b/src/glsl/opt_algebraic.cpp > @@ -589,6 +589,10 @@ ir_algebraic_visitor::handle_expression(ir_expression > *ir) > /* Found a min (max(x, 0), 1.0) */ > if (outer_const->is_one() && inner_val_a->is_zero()) > return saturate(inner_val_b); > + > + /* Found a min (max(x, 0.0) b), where b < 1.0 */ > + if ((outer_const->get_float_component(0) < 1.0f) && > inner_val_b->is_zero()) > + return saturate(expr(ir_binop_min, inner_val_a, outer_const));
Not sure about other GPU's, but on reasonably modern nvidia gpu's, in addition to being able to just saturate a single var, some other instructions take a "saturate" modifier (like fp add/multiply). But not min/max. If you were to write this as min(saturate(a), b) then it would be easier to propagate the saturate as a modifier to whatever expression produces 'a' without having a clever optimization that moves it through min/max. Cheers, -ilia > } > } > > -- > 1.9.1 > > _______________________________________________ > mesa-dev mailing list > mesa-dev@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/mesa-dev _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
