From: Eric Anholt <eric@anholt.net>
Date: Fri, 11 Mar 2011 21:17:03 +0000 (-0800)
Subject: glsl: Reduce processing of expression trees in do_structure_splitting.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=05cf1ad82eb903eb07d7b379d0ea610bb43dd84a;p=mesa.git

glsl: Reduce processing of expression trees in do_structure_splitting.

Most of the time we don't have a non-uniform struct variable in the
shader, so this cuts the time spent in do_structure_splitting during
glean texCombine by about 2/3.
---

diff --git a/src/glsl/opt_structure_splitting.cpp b/src/glsl/opt_structure_splitting.cpp
index 014407c0be2..2c1f6bb227a 100644
--- a/src/glsl/opt_structure_splitting.cpp
+++ b/src/glsl/opt_structure_splitting.cpp
@@ -151,6 +151,12 @@ ir_structure_reference_visitor::visit_enter(ir_dereference_record *ir)
 ir_visitor_status
 ir_structure_reference_visitor::visit_enter(ir_assignment *ir)
 {
+   /* If there are no structure references yet, no need to bother with
+    * processing the expression tree.
+    */
+   if (this->variable_list.is_empty())
+      return visit_continue_with_parent;
+
    if (ir->lhs->as_dereference_variable() &&
        ir->rhs->as_dereference_variable() &&
        !ir->condition) {