Optimizer - Began working on constant folding

Makefile

@@ -34,6 +34,7 @@ COMMON = \
 	 \
 	 c-ops.cc \
 	 c-opast.cc \
+	 c-opopt.cc \
 	 c-opparser.cc \
 	 c-opcomp.cc \
 	 c-opmgr.cc \

c-opast.hh

@@ -215,6 +215,9 @@ class T_ArgumentNode : public A_Node
 		{ return *expr_; }
 	bool isIdentifier( ) const noexcept
 		{ return expr_->type( ) == EXPR_ID; }
+
+	void expression( P_ExpressionNode expr ) noexcept
+		{ assert( expr ); expr_ = std::move( expr ); }
 };
 using P_ArgumentNode = T_OwnPtr< T_ArgumentNode >;
 
@@ -454,6 +457,9 @@ class T_CondInstrNode : public A_InstructionNode
 
 		A_ExpressionNode& expression( ) const noexcept
 			{ return *expression_; }
+
+		void expression( P_ExpressionNode expr ) noexcept
+			{ assert( expr ); expression_ = std::move( expr ); }
 	};
 
 	class T_ValuedCase : public A_Node

c-opopt.cc

@@ -0,0 +1,172 @@
+#include "externals.hh"
+
+#include "c-opopt.hh"
+#include "c-sync.hh"
+
+using namespace ebcl;
+using namespace opast;
+using namespace opopt;
+
+
+// Macro to use either the specified visitor or a visitor created just for the
+// occation
+#define M_VISITOR_( E ) \
+	T_OwnPtr< T_Visitor< A_Node > > localVisitor_; \
+	if ( !(E) ) { \
+		localVisitor_ = NewOwned< T_Visitor< A_Node > >( ASTVisitorBrowser ); \
+	} \
+	T_Visitor< A_Node >& visitor{ (E) ? *(E) : *localVisitor_ }
+
+
+
+/*= CONSTANT FOLDING =========================================================*/
+
+namespace {
+
+struct T_ConstantFolder_
+{
+	// Input
+	T_Optional< std::pair< uint32_t , uint32_t > > fixedSize;
+	T_SyncCurves const* curves;
+
+	// Result
+	bool didFold{ false };
+
+	bool operator()( A_Node& node , bool exit ) noexcept;
+
+    private:
+	using F_ExprGet_ = std::function< A_ExpressionNode&( A_Node& ) >;
+	using F_ExprSet_ = std::function< void( A_Node& , P_ExpressionNode ) >;
+
+	void handleParentNode(
+			A_Node& node ,
+			F_ExprGet_ get ,
+			F_ExprSet_ set ) noexcept;
+
+	P_ExpressionNode checkExpression(
+			A_ExpressionNode const& node ) noexcept;
+};
+
+/*----------------------------------------------------------------------------*/
+
+bool T_ConstantFolder_::operator()(
+		A_Node& node ,
+		const bool exit ) noexcept
+{
+	if ( exit ) {
+		return true;
+	}
+
+	switch ( node.type( ) ) {
+
+	    case A_Node::TN_ARG:
+		handleParentNode( node ,
+			[]( A_Node& n ) -> A_ExpressionNode& {
+				return ((T_ArgumentNode&)n).expression( );
+			} ,
+			[]( A_Node& n , P_ExpressionNode e ) {
+				((T_ArgumentNode&)n).expression( std::move( e ) );
+			} );
+		return false;
+
+	    case A_Node::TN_CONDITION:
+		handleParentNode( node ,
+			[]( A_Node& n ) -> A_ExpressionNode& {
+				return ((T_CondInstrNode::T_Expression&)n).expression( );
+			} ,
+			[]( A_Node& n , P_ExpressionNode e ) {
+				((T_CondInstrNode::T_Expression&)n).expression( std::move( e ) );
+			} );
+		return false;
+
+	    case A_Node::OP_SET:
+		handleParentNode( node ,
+			[]( A_Node& n ) -> A_ExpressionNode& {
+				return ((T_SetInstrNode&)n).expression( );
+			} ,
+			[]( A_Node& n , P_ExpressionNode e ) {
+				((T_SetInstrNode&)n).setExpression( std::move( e ) );
+			} );
+		return false;
+
+	    default:
+		return true;
+	}
+}
+
+void T_ConstantFolder_::handleParentNode(
+		A_Node& node ,
+		F_ExprGet_ get ,
+		F_ExprSet_ set ) noexcept
+{
+	auto r{ checkExpression( get( node ) ) };
+	if ( r ) {
+		set( node , std::move( r ) );
+		didFold = true;
+	}
+}
+
+/*----------------------------------------------------------------------------*/
+
+P_ExpressionNode T_ConstantFolder_::checkExpression(
+		A_ExpressionNode const& node ) noexcept
+{
+#warning TODO optimize the fuck
+	// 1/ Replace inputs with value if no curve/constant curve
+	//    Replace $width/$height with value if fixedSize
+	// 2/ Replace UnOp( Cnst ) with result
+	//    Replace BinOp( Cnst , Cnst ) with result
+	// 3/ Try to find other optimisations, e.g. for Add( Cnst , Add( Cnst , Expr ) )
+
+	if ( node.type( ) == A_Node::EXPR_ID ) {
+		if ( !fixedSize ) {
+			return {};
+		}
+
+		T_IdentifierExprNode& n{ (T_IdentifierExprNode&) node };
+		if ( n.id( ) == "width" ) {
+			auto c{ NewOwned< T_ConstantExprNode >( n.parent( ) ,
+					double( fixedSize->first ) ) };
+			c->location( ) = n.location( );
+			return c;
+		}
+		if ( n.id( ) == "height" ) {
+			auto c{ NewOwned< T_ConstantExprNode >( n.parent( ) ,
+					float( fixedSize->second ) ) };
+			c->location( ) = n.location( );
+			return c;
+		}
+		return {};
+	}
+
+	return {};
+}
+
+} // namespace <anon>
+
+
+bool opopt::FoldConstants(
+		T_RootNode& root ,
+		const T_Optional< std::pair< uint32_t , uint32_t > > fixedSize ,
+		T_SyncCurves const* curves ,
+		T_Visitor< A_Node >* const extVisitor ) noexcept
+{
+	M_VISITOR_( extVisitor );
+	T_ConstantFolder_ folder;
+	folder.fixedSize = fixedSize;
+	folder.curves = curves;
+	visitor.visit( root , folder );
+	return folder.didFold;
+}
+
+
+/*= DEAD CODE REMOVAL ========================================================*/
+
+bool opopt::RemoveDeadCode( opast::T_RootNode& root ,
+		ebcl::T_Visitor< opast::A_Node >* extVisitor ) noexcept
+{
+	M_VISITOR_( extVisitor );
+
+#warning blargh
+	return false;
+}

c-opopt.hh

@@ -0,0 +1,37 @@
+#pragma once
+#include "c-opast.hh"
+
+#include <ebcl/Algorithms.hh>
+
+struct T_SyncCurves;
+
+namespace opopt {
+
+// Attempts to fold constant expressions into single constants. Returns true if
+// transformations were made, false if not.
+//
+// Parameters:
+//	root		the root node
+//	fixedSize	the size of the output, if it is fixed
+//	curves		the curves that will be bound to the inputs
+//	extVisitor	a node visitor instance to be used instead of creating
+//			one
+//
+bool FoldConstants( opast::T_RootNode& root ,
+		T_Optional< std::pair< uint32_t , uint32_t > > fixedSize = { } ,
+		T_SyncCurves const* curves = nullptr ,
+		ebcl::T_Visitor< opast::A_Node >* extVisitor = nullptr ) noexcept;
+
+// Attempt to remove blocks of code that will not be executed because of
+// constant conditions. Returns true if transformations were made, false if not.
+//
+// Parameters:
+//	root		the root node
+//	extVisitor	a node visitor instance to be used instead of creating
+//			one
+//
+bool RemoveDeadCode( opast::T_RootNode& root ,
+		ebcl::T_Visitor< opast::A_Node >* extVisitor = nullptr ) noexcept;
+
+
+} // namespace opopt