Reorder declarations in shaders

[libs/gl.git] / source / programcompiler.cpp

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index 86ea8da93d7e6866590a563c150555393903cafe..7224df1efba672d4afb7ecb12923a0109ae9f6f6 100644 (file)
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -165,14 +165,13 @@ void ProgramCompiler::generate(Stage &stage)
        apply<InterfaceGenerator>(stage);
        apply<VariableResolver>(stage);
        apply<VariableRenamer>(stage);
+       apply<DeclarationReorderer>(stage);
        apply<LegacyConverter>(stage);
-       apply<VariableResolver>(stage);
 }
 
 bool ProgramCompiler::optimize(Stage &stage)
 {
        apply<ConstantConditionEliminator>(stage);
-       apply<VariableResolver>(stage);
 
        set<Node *> unused = apply<UnusedVariableLocator>(stage);
        set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
@@ -919,6 +918,45 @@ void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
 }
 
 
+ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
+       kind(NO_DECLARATION)
+{ }
+
+void ProgramCompiler::DeclarationReorderer::visit(Block &block)
+{
+       list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
+       list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
+
+       for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+       {
+               kind = NO_DECLARATION;
+               (*i)->visit(*this);
+
+               bool moved = false;
+               if(kind==STRUCT && struct_insert_point!=block.body.end())
+               {
+                       block.body.insert(struct_insert_point, *i);
+                       moved = true;
+               }
+               else if(kind>STRUCT && struct_insert_point==block.body.end())
+                       struct_insert_point = i;
+
+               if(kind==VARIABLE && variable_insert_point!=block.body.end())
+               {
+                       block.body.insert(variable_insert_point, *i);
+                       moved = true;
+               }
+               else if(kind>VARIABLE && variable_insert_point==block.body.end())
+                       variable_insert_point = i;
+
+               if(moved)
+                       block.body.erase(i++);
+               else
+                       ++i;
+       }
+}
+
+
 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
        variable_values(0),
        result(0.0f),