From 0e2ba3ee827f77af0b1f322d95c650f6f7f4da88 Mon Sep 17 00:00:00 2001 From: Abdiel Janulgue Date: Tue, 8 Jul 2014 14:12:50 +0300 Subject: glsl: Optimize clamp(x, b, 1.0), where b > 0.0 as max(saturate(x),b) v2: - Output max(saturate(x),b) instead of saturate(max(x,b)) - Make sure we do component-wise comparison for vectors (Ian Romanick) v3: - Add missing condition where the outer constant value is > 0.0 and inner constant is 1.0. - Fix comments to show that the optimization is a commutative operation (Matt Turner) Reviewed-by: Ian Romanick Signed-off-by: Abdiel Janulgue --- src/glsl/opt_algebraic.cpp | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'src/glsl') diff --git a/src/glsl/opt_algebraic.cpp b/src/glsl/opt_algebraic.cpp index 6dfb6819820..447618f9ef9 100644 --- a/src/glsl/opt_algebraic.cpp +++ b/src/glsl/opt_algebraic.cpp @@ -137,6 +137,21 @@ is_less_than_one(ir_constant *ir) return (component == ir->type->vector_elements); } +static inline bool +is_greater_than_zero(ir_constant *ir) +{ + if (!is_valid_vec_const(ir)) + return false; + + unsigned component = 0; + for (int c = 0; c < ir->type->vector_elements; c++) { + if (ir->get_float_component(c) > 0.0f) + component++; + } + + return (component == ir->type->vector_elements); +} + static void update_type(ir_expression *ir) { @@ -684,6 +699,14 @@ ir_algebraic_visitor::handle_expression(ir_expression *ir) if (is_less_than_one(inner_val_b->as_constant()) && outer_const->is_zero()) return expr(ir_binop_min, saturate(inner_val_a), inner_val_b); + + /* Found a {min|max} ({max|min} (x, b), 1.0), where b > 0.0 + * and its variations + */ + if (outer_const->is_one() && is_greater_than_zero(inner_val_b->as_constant())) + return expr(ir_binop_max, saturate(inner_val_a), inner_val_b); + if (inner_val_b->as_constant()->is_one() && is_greater_than_zero(outer_const)) + return expr(ir_binop_max, saturate(inner_val_a), outer_const); } } -- cgit v1.2.3