public ExprMathNodeForgeEval(
ExprMathNodeForge forge,
ExprEvaluator evaluatorLeft,
ExprEvaluator evaluatorRight)
{
this.forge = forge;
this.evaluatorLeft = evaluatorLeft;
this.evaluatorRight = evaluatorRight;
}
public static CodegenMethod Codegen(
ExprMathNodeForge forge,
CodegenMethodScope codegenMethodScope,
ExprForgeCodegenSymbol exprSymbol,
CodegenClassScope codegenClassScope,
ExprNode lhs,
ExprNode rhs)
{
var methodNode = codegenMethodScope.MakeChild(
forge.EvaluationType,
typeof(ExprMathNodeForgeEval),
codegenClassScope);
var lhsType = lhs.Forge.EvaluationType;
var rhsType = rhs.Forge.EvaluationType;
var block = methodNode.Block
.DeclareVar(
lhsType,
"left",
lhs.Forge.EvaluateCodegen(lhsType, methodNode, exprSymbol, codegenClassScope));
if (lhsType.CanBeNull()) {
block.IfRefNullReturnNull("left");
}
block.DeclareVar(
rhsType,
"right",
rhs.Forge.EvaluateCodegen(rhsType, methodNode, exprSymbol, codegenClassScope));
if (rhsType.CanBeNull()) {
block.IfRefNullReturnNull("right");
}
block.MethodReturn(
CodegenLegoCast.CastSafeFromObjectType(
forge.EvaluationType,
forge.ArithTypeEnumComputer.Codegen(
methodNode,
codegenClassScope,
Ref("left"),
Ref("right"),
lhsType,
rhsType)));
return methodNode;
}
public override ExprNode Validate(ExprValidationContext validationContext)
{
if (ChildNodes.Length != 2) {
throw new ExprValidationException("Arithmatic node must have 2 parameters");
}
foreach (var child in ChildNodes) {
var childType = child.Forge.EvaluationType;
if (!childType.IsNumeric()) {
throw new ExprValidationException(
"Implicit conversion from datatype '" +
childType.CleanName() +
"' to numeric is not allowed");
}
}
// Determine result type, set up compute function
var lhs = ChildNodes[0];
var rhs = ChildNodes[1];
var lhsType = lhs.Forge.EvaluationType;
var rhsType = rhs.Forge.EvaluationType;
Type resultType;
// If both sides are unboxed, then the result is also unboxed
if (!lhsType.IsNullable() && !rhsType.IsNullable()) {
if ((lhsType == typeof(short)) && (rhsType == typeof(short))) {
resultType = typeof(int);
} else if (lhsType == typeof(byte) && (rhsType == typeof(byte))) {
resultType = typeof(int);
} else if (lhsType == rhsType) {
resultType = rhsType;
}
else {
resultType = lhsType
.GetArithmaticCoercionType(rhsType)
.GetUnboxedType();
}
}
else if ((lhsType == typeof(short) || lhsType == typeof(short?)) &&
(rhsType == typeof(short) || rhsType == typeof(short?))) {
resultType = typeof(int?);
}
else if ((lhsType == typeof(byte) || lhsType == typeof(byte?)) &&
(rhsType == typeof(byte) || rhsType == typeof(byte?))) {
resultType = typeof(int?);
}
else if (lhsType == rhsType) {
resultType = rhsType.GetBoxedType();
}
else {
resultType = lhsType.GetArithmaticCoercionType(rhsType);
}
if (MathArithTypeEnum == MathArithTypeEnum.DIVIDE && !_isIntegerDivision) {
if (!resultType.IsDecimal()) {
resultType = typeof(double?);
}
}
// If ths isDivisionByZeroReturnsNull is set, it requires promotion to boxed types
// to support passing back null.
if (_isDivisionByZeroReturnsNull) {
resultType = resultType.GetBoxedType();
}
var arithTypeEnumComputer = MathArithType.GetComputer(
MathArithTypeEnum,
resultType,
lhsType,
rhsType,
_isIntegerDivision,
_isDivisionByZeroReturnsNull,
validationContext.ImportService.DefaultMathContext);
_forge = new ExprMathNodeForge(this, arithTypeEnumComputer, resultType);
return null;
}