using CLanguage.Types; using System; namespace CLanguage.Syntax { public abstract class Expression { public Location Location { get; set; } public bool HasError { get; set; } public void Emit(EmitContext ec) { DoEmit(ec); } public abstract CType GetEvaluatedCType(EmitContext ec); protected abstract void DoEmit(EmitContext ec); protected static int GetInstructionOffset(CBasicType aType, EmitContext ec) { if (!aType.IsIntegral) throw new NotSupportedException("Arithmetic on type '" + aType + "'"); int num = 0; switch (aType.GetSize(ec)) { case 2: num = 0; break; case 4: num = 2; break; default: throw new NotSupportedException("Arithmetic on type '" + aType + "'"); } if (aType.Signedness == Signedness.Unsigned) num++; return num; } protected static CBasicType GetPromotedType(Expression expr, string op, EmitContext ec) { CType evaluatedCType = expr.GetEvaluatedCType(ec); CBasicType cBasicType = evaluatedCType as CBasicType; if (cBasicType == null) { ec.Report.Error(19, "Operator '" + op + "' cannot be applied to operand of type '" + evaluatedCType + "'"); return CBasicType.SignedInt; } return cBasicType.IntegerPromote(ec); } protected static CBasicType GetArithmeticType(Expression leftExpr, Expression rightExpr, string op, EmitContext ec) { CType evaluatedCType = leftExpr.GetEvaluatedCType(ec); CType evaluatedCType2 = rightExpr.GetEvaluatedCType(ec); CBasicType cBasicType = evaluatedCType as CBasicType; CBasicType cBasicType2 = evaluatedCType2 as CBasicType; if (cBasicType == null || cBasicType2 == null) { ec.Report.Error(19, "Operator '" + op + "' cannot be applied to operands of type '" + evaluatedCType + "' and '" + evaluatedCType2 + "'"); return CBasicType.SignedInt; } return cBasicType.ArithmeticConvert(cBasicType2, ec); } } }