Remove expression statements without side effects

[libs/gl.git] / source / glsl / optimize.cpp

diff --git a/source/glsl/optimize.cpp b/source/glsl/optimize.cpp
index 2215f8335cd06a23ea71e2c381cb1776362b81cd..d6e5fa5592576ce3080bd46afb756d8e7dbb5c1e 100644 (file)
--- a/source/glsl/optimize.cpp
+++ b/source/glsl/optimize.cpp
@@ -39,14 +39,54 @@ void InlineableFunctionLocator::visit(FunctionDeclaration &func)
 }
 
 
+void InlineDependencyCollector::visit(VariableReference &var)
+{
+       if(var.declaration)
+       {
+               dependencies.insert(var.declaration);
+               var.declaration->visit(*this);
+       }
+}
+
+void InlineDependencyCollector::visit(InterfaceBlockReference &iface)
+{
+       if(iface.declaration)
+       {
+               dependencies.insert(iface.declaration);
+               iface.declaration->visit(*this);
+       }
+}
+
+void InlineDependencyCollector::visit(FunctionCall &call)
+{
+       if(call.declaration)
+               dependencies.insert(call.declaration);
+       TraversingVisitor::visit(call);
+}
+
+void InlineDependencyCollector::visit(VariableDeclaration &var)
+{
+       if(var.type_declaration)
+       {
+               dependencies.insert(var.type_declaration);
+               var.type_declaration->visit(*this);
+       }
+}
+
+
 FunctionInliner::FunctionInliner():
-       extract_result(0)
+       current_function(0),
+       extract_result(0),
+       any_inlined(false)
 { }
 
-void FunctionInliner::apply(Stage &stage)
+bool FunctionInliner::apply(Stage &s)
 {
-       inlineable = InlineableFunctionLocator().apply(stage);
-       stage.content.visit(*this);
+       stage = &s;
+       inlineable = InlineableFunctionLocator().apply(s);
+       any_inlined = false;
+       s.content.visit(*this);
+       return any_inlined;
 }
 
 void FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
@@ -54,7 +94,10 @@ void FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
        inline_result = 0;
        ptr->visit(*this);
        if(inline_result)
+       {
                ptr = inline_result;
+               any_inlined = true;
+       }
 }
 
 void FunctionInliner::visit(Block &block)
@@ -102,6 +145,9 @@ void FunctionInliner::visit(FunctionCall &call)
        {
                extract_result = 2;
                def->visit(*this);
+
+               if(inline_result)
+                       NodeReorderer().apply(*stage, *current_function, InlineDependencyCollector().apply(*def));
        }
        else
                inline_result = 0;
@@ -114,6 +160,12 @@ void FunctionInliner::visit(VariableDeclaration &var)
        inline_result = 0;
 }
 
+void FunctionInliner::visit(FunctionDeclaration &func)
+{
+       SetForScope<FunctionDeclaration *> set_func(current_function, &func);
+       TraversingVisitor::visit(func);
+}
+
 void FunctionInliner::visit(Return &ret)
 {
        TraversingVisitor::visit(ret);
@@ -231,7 +283,8 @@ UnusedVariableRemover::UnusedVariableRemover():
        aggregate(0),
        assignment(0),
        assignment_target(false),
-       assign_to_subscript(false)
+       assign_to_subscript(false),
+       side_effects(false)
 { }
 
 bool UnusedVariableRemover::apply(Stage &stage)
@@ -281,6 +334,13 @@ void UnusedVariableRemover::visit(MemberAccess &memacc)
        unused_nodes.erase(memacc.declaration);
 }
 
+void UnusedVariableRemover::visit(UnaryExpression &unary)
+{
+       TraversingVisitor::visit(unary);
+       if(unary.oper=="++" || unary.oper=="--")
+               side_effects = true;
+}
+
 void UnusedVariableRemover::visit(BinaryExpression &binary)
 {
        if(binary.oper=="[")
@@ -304,6 +364,13 @@ void UnusedVariableRemover::visit(Assignment &assign)
        }
        assign.right->visit(*this);
        assignment = &assign;
+       side_effects = true;
+}
+
+void UnusedVariableRemover::visit(FunctionCall &call)
+{
+       TraversingVisitor::visit(call);
+       side_effects = true;
 }
 
 void UnusedVariableRemover::record_assignment(VariableDeclaration &var, Node &node, bool chained)
@@ -328,9 +395,12 @@ void UnusedVariableRemover::clear_assignments(VariableInfo &var_info, bool mark_
 void UnusedVariableRemover::visit(ExpressionStatement &expr)
 {
        assignment = 0;
+       side_effects = false;
        TraversingVisitor::visit(expr);
        if(assignment && assignment->target_declaration)
                record_assignment(*assignment->target_declaration, expr, (assignment->self_referencing || assign_to_subscript));
+       if(!side_effects)
+               unused_nodes.insert(&expr);
 }
 
 void UnusedVariableRemover::visit(StructDeclaration &strct)