Shader: Add support for while loops

src/Nazara/Shader/Ast/AstCloner.cpp

@@ -193,6 +193,15 @@ namespace Nz::ShaderAst
 		return clone;
 	}
 
+	StatementPtr AstCloner::Clone(WhileStatement& node)
+	{
+		auto clone = std::make_unique<WhileStatement>();
+		clone->condition = CloneExpression(node.condition);
+		clone->body = CloneStatement(node.body);
+
+		return clone;
+	}
+
 	ExpressionPtr AstCloner::Clone(AccessIdentifierExpression& node)
 	{
 		auto clone = std::make_unique<AccessIdentifierExpression>();

src/Nazara/Shader/Ast/AstRecursiveVisitor.cpp

@@ -175,4 +175,13 @@ namespace Nz::ShaderAst
 		if (node.returnExpr)
 			node.returnExpr->Visit(*this);
 	}
+
+	void AstRecursiveVisitor::Visit(WhileStatement& node)
+	{
+		if (node.condition)
+			node.condition->Visit(*this);
+
+		if (node.body)
+			node.body->Visit(*this);
+	}
 }

src/Nazara/Shader/Ast/AstSerializer.cpp

@@ -318,6 +318,12 @@ namespace Nz::ShaderAst
 		Node(node.returnExpr);
 	}
 
+	void AstSerializerBase::Serialize(WhileStatement& node)
+	{
+		Node(node.condition);
+		Node(node.body);
+	}
+
 	void ShaderAstSerializer::Serialize(StatementPtr& shader)
 	{
 		m_stream << s_magicNumber << s_currentVersion;

src/Nazara/Shader/Ast/SanitizeVisitor.cpp

@@ -460,12 +460,11 @@ namespace Nz::ShaderAst
 		{
 			case Identifier::Type::Constant:
 			{
-				// Replace IdentifierExpression by ConstantExpression
-				auto constantExpr = std::make_unique<ConstantExpression>();
-				constantExpr->cachedExpressionType = GetExpressionType(m_context->constantValues[identifier->index]);
-				constantExpr->constantId = identifier->index;
+				// Replace IdentifierExpression by Constant(Value)Expression
+				ConstantExpression constantExpr;
+				constantExpr.constantId = identifier->index;
 
-				return constantExpr;
+				return Clone(constantExpr); //< Turn ConstantExpression into ConstantValueExpression
 			}
 
 			case Identifier::Type::Variable:
@@ -951,6 +950,19 @@ namespace Nz::ShaderAst
 		return clone;
 	}
 
+	StatementPtr SanitizeVisitor::Clone(WhileStatement& node)
+	{
+		MandatoryExpr(node.condition);
+		MandatoryStatement(node.body);
+
+		auto clone = static_unique_pointer_cast<WhileStatement>(AstCloner::Clone(node));
+
+		if (GetExpressionType(*clone->condition) != ExpressionType{ PrimitiveType::Boolean })
+			throw AstError{ "expected a boolean value" };
+
+		return clone;
+	}
+
 	auto SanitizeVisitor::FindIdentifier(const std::string_view& identifierName) const -> const Identifier*
 	{
 		auto it = std::find_if(m_context->identifiersInScope.rbegin(), m_context->identifiersInScope.rend(), [&](const Identifier& identifier) { return identifier.name == identifierName; });