On Mon, Jul 7, 2014 at 7:18 PM, Matt Turner <matts...@gmail.com> wrote: > On Mon, Jul 7, 2014 at 6:57 AM, Abdiel Janulgue > <abdiel.janul...@linux.intel.com> wrote: >> v2: Check that the base type is float (Ian Romanick) >> >> Signed-off-by: Abdiel Janulgue <abdiel.janul...@linux.intel.com> >> --- >> src/glsl/opt_algebraic.cpp | 34 ++++++++++++++++++++++++++++++++++ >> 1 file changed, 34 insertions(+) >> >> diff --git a/src/glsl/opt_algebraic.cpp b/src/glsl/opt_algebraic.cpp >> index ac7514a..2ad561c 100644 >> --- a/src/glsl/opt_algebraic.cpp >> +++ b/src/glsl/opt_algebraic.cpp >> @@ -614,6 +614,40 @@ ir_algebraic_visitor::handle_expression(ir_expression >> *ir) >> >> break; >> >> + case ir_binop_min: >> + case ir_binop_max: >> + if (ir->type->base_type != GLSL_TYPE_FLOAT) >> + break; >> + /* Replace min(max) operations and its commutative combinations with >> + * a saturate operation >> + */ >> + for (int op = 0; op < 2; op++) { >> + ir_expression *minmax = op_expr[op]; >> + ir_constant *outer_const = op_const[(op == 0) ? 1 : 0]; > > We use (1 - op) in other places in opt_algebraic. (Same comment below) > >> + ir_expression_operation op_cond = (ir->operation == ir_binop_max) ? >> + ir_binop_min : ir_binop_max; >> + >> + if (!minmax || !outer_const || (minmax->operation != op_cond)) >> + continue; >> + >> + /* Found a min/max operation. Now try to see if its operands >> + * meet our conditions that we can do just a single saturate >> operation >> + */ >> + for (int minmax_op = 0; minmax_op < 2; minmax_op++) { >> + ir_rvalue *inner_val_a = minmax->operands[minmax_op]; >> + ir_rvalue *inner_val_b = minmax->operands[(minmax_op == 0) ? 1 >> : 0]; >> + >> + if (!inner_val_a || !inner_val_b) >> + continue; >> + >> + /* Found a min (max(x, 0), 1.0) */ > > This comment tripped me up for a second. This really means that you've > found either > > - min(max(x, 0.0), 1.0); or > - max(min(x, 1.0), 0.0)
Hmm, but are optimizing both of these to saturate OK? Shouldn't min(max(NaN, 0.0), 1.0) give 0.0, whereas max(min(NaN, 1.0), 0.0) give 1.0? _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev