Reorder declarations in shaders

So that structs appear before variables and variables appear before
functions.  This ensures that the declarations stay visible if an
expression is moved to an earlier point while inlining functions.

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index fdb2576eff5afb14c6870c02ddd5e013bf2182b3..7224df1efba672d4afb7ecb12923a0109ae9f6f6 100644 (file)
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -165,6 +165,7 @@ void ProgramCompiler::generate(Stage &stage)
        apply<InterfaceGenerator>(stage);
        apply<VariableResolver>(stage);
        apply<VariableRenamer>(stage);
+       apply<DeclarationReorderer>(stage);
        apply<LegacyConverter>(stage);
 }
 
@@ -917,6 +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),

diff --git a/source/programcompiler.h b/source/programcompiler.h
index 398bb214d10568800d69e757dec8eadad82efda5..8c4034d4e906baae7812ee66ecc1b84abff39448 100644 (file)
--- a/source/programcompiler.h
+++ b/source/programcompiler.h
@@ -156,6 +156,29 @@ private:
                virtual void visit(ProgramSyntax::VariableDeclaration &);
        };
 
+       struct DeclarationReorderer: Visitor
+       {
+               enum DeclarationKind
+               {
+                       NO_DECLARATION,
+                       LAYOUT,
+                       STRUCT,
+                       VARIABLE,
+                       FUNCTION
+               };
+
+               DeclarationKind kind;
+
+               DeclarationReorderer();
+
+               virtual void visit(ProgramSyntax::Block &);
+               virtual void visit(ProgramSyntax::InterfaceLayout &) { kind = LAYOUT; }
+               virtual void visit(ProgramSyntax::StructDeclaration &) { kind = STRUCT; }
+               virtual void visit(ProgramSyntax::VariableDeclaration &) { kind = VARIABLE; }
+               virtual void visit(ProgramSyntax::InterfaceBlock &) { kind = VARIABLE; }
+               virtual void visit(ProgramSyntax::FunctionDeclaration &) { kind = FUNCTION; }
+       };
+
        struct ExpressionEvaluator: ProgramSyntax::NodeVisitor
        {
                typedef std::map<ProgramSyntax::VariableDeclaration *, ProgramSyntax::Expression *> ValueMap;