private bool ParseExpression(TokenReader reader, out Expression result)
{
result = null;
Token start = reader.Peek();
Expression firstTerm = null;
if (!this.ParseSimpleExpression(reader, out firstTerm))
{
return false;
}
Token tok = reader.Peek();
if (tok.IsRelationalOperator())
{
reader.Read();
Expression term = null;
if (!this.ParseSimpleExpression(reader, out term))
{
return false;
}
result = new RelationalExpression(start, firstTerm, ((KeywordToken)tok).Value, term);
}
else
{
result = firstTerm;
}
return true;
}
private bool TryEmitRelationExpresion(
RelationalExpression relExpr,
CompilerContext context,
Scope scope,
MethodImpl method,
out TypeDefinition valueType)
{
context.TryFindTypeByName("boolean", out valueType);
TypeDefinition rightSideType = null;
if (!this.TryEmitExpression(relExpr.Right, context, scope, method, out rightSideType))
{
return false;
}
this.PushResult(method, rightSideType);
TypeDefinition leftSideType = null;
if (!this.TryEmitExpression(relExpr.Left, context, scope, method, out leftSideType))
{
return false;
}
if (rightSideType.IsFloatingPoint)
{
if (leftSideType.IsFloatingPoint)
{
switch (rightSideType.Size)
{
case 4:
method.Statements.Add(new AsmStatement { Instruction = "fld dword ptr [esp]" });
break;
case 8:
method.Statements.Add(new AsmStatement { Instruction = "fld qword ptr [esp]" });
break;
default:
method.Statements.Add(new AsmStatement { Instruction = "fld tword ptr [esp]" });
break;
}
method.Statements.Add(new AsmStatement { Instruction = string.Format("add esp,{0}", rightSideType.Size) });
method.Statements.Add(new AsmStatement { Instruction = "fcompp" });
method.Statements.Add(new AsmStatement { Instruction = "fnstsw ax" });
method.Statements.Add(new AsmStatement { Instruction = "sahf" });
switch (relExpr.Operator)
{
case Keyword.Equals:
{
method.Statements.Add(new AsmStatement { Instruction = "sete al" });
} break;
case Keyword.LessThan:
{
method.Statements.Add(new AsmStatement { Instruction = "seta al" });
} break;
case Keyword.LessThanOrEquals:
{
method.Statements.Add(new AsmStatement { Instruction = "setae al" });
} break;
case Keyword.GreaterThan:
{
method.Statements.Add(new AsmStatement { Instruction = "setb al" });
} break;
case Keyword.GreaterThanOrEquals:
{
method.Statements.Add(new AsmStatement { Instruction = "setbe al" });
} break;
case Keyword.NotEqual:
{
method.Statements.Add(new AsmStatement { Instruction = "setne al" });
} break;
}
}
else
{
string message = string.Format(
System.Globalization.CultureInfo.InvariantCulture,
Properties.Resources.CodeGenerator_NoAutomaticConversion,
leftSideType.FullName,
rightSideType.FullName);
this.log.Write(new Message(
relExpr.Start.Path,
relExpr.Start.Line,
relExpr.Start.Column,
Severity.Error,
message));
return false;
}
}
else if(leftSideType.IsFloatingPoint)
{
string message = string.Format(
System.Globalization.CultureInfo.InvariantCulture,
Properties.Resources.CodeGenerator_NoAutomaticConversion,
leftSideType.FullName,
rightSideType.FullName);
this.log.Write(new Message(
relExpr.Start.Path,
relExpr.Start.Line,
relExpr.Start.Column,
Severity.Error,
message));
return false;
}
else
{
if(leftSideType.Size <= 4 && rightSideType.Size <= 4)
{
method.Statements.Add(new AsmStatement { Instruction = "pop ecx"});
method.Statements.Add(new AsmStatement { Instruction = "cmp eax,ecx"});
switch (relExpr.Operator)
{
case Keyword.Equals:
{
method.Statements.Add(new AsmStatement { Instruction = "sete al" });
} break;
case Keyword.LessThan:
{
method.Statements.Add(new AsmStatement { Instruction = "setl al" });
} break;
case Keyword.LessThanOrEquals:
{
method.Statements.Add(new AsmStatement { Instruction = "setle al" });
} break;
case Keyword.GreaterThan:
{
method.Statements.Add(new AsmStatement { Instruction = "setg al" });
} break;
case Keyword.GreaterThanOrEquals:
{
method.Statements.Add(new AsmStatement { Instruction = "setge al" });
} break;
case Keyword.NotEqual:
{
method.Statements.Add(new AsmStatement { Instruction = "setne al" });
} break;
}
}
}
return true;
}
