public override void EmitBranchFalse(CodeGen cg, Label label)
{
if (NodeType == AstNodeType.Not)
{
_operand.EmitBranchTrue(cg, label);
}
else
{
base.EmitBranchFalse(cg, label);
}
}
private bool EmitBranchTrue(CodeGen cg, AstNodeType nodeType, Label label)
{
switch (nodeType)
{
case AstNodeType.GreaterThan:
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Bgt, label);
cg.EmitSequencePointNone();
return(true);
case AstNodeType.GreaterThanOrEqual:
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Bge, label);
cg.EmitSequencePointNone();
return(true);
case AstNodeType.LessThan:
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Blt, label);
cg.EmitSequencePointNone();
return(true);
case AstNodeType.LessThanOrEqual:
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Ble, label);
cg.EmitSequencePointNone();
return(true);
case AstNodeType.Equal:
if (_left.IsConstant(null))
{
_right.EmitAsObject(cg);
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Brfalse, label);
cg.EmitSequencePointNone();
}
else if (_right.IsConstant(null))
{
_left.EmitAsObject(cg);
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Brfalse, label);
cg.EmitSequencePointNone();
}
else
{
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Beq, label);
cg.EmitSequencePointNone();
}
return(true);
case AstNodeType.NotEqual:
if (_left.IsConstant(null))
{
_right.EmitAsObject(cg);
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Brtrue, label);
cg.EmitSequencePointNone();
}
else if (_right.IsConstant(null))
{
_left.EmitAsObject(cg);
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Brtrue, label);
cg.EmitSequencePointNone();
}
else
{
_left.EmitAs(cg, GetEmitType());
_right.EmitAs(cg, GetEmitType());
//cg.Emit(OpCodes.Ceq);
cg.EmitSequencePointNone();
cg.Emit(OpCodes.Bne_Un, label);
cg.EmitSequencePointNone();
}
return(true);
case AstNodeType.AndAlso:
// if (left AND right) branch label
// if (left) then
// if (right) branch label
// endif
Label endif = cg.DefineLabel();
_left.EmitBranchFalse(cg, endif);
_right.EmitBranchTrue(cg, label);
cg.MarkLabel(endif);
return(true);
case AstNodeType.OrElse:
// if (left OR right) branch label
// if (left) then branch label endif
// if (right) then branch label endif
_left.EmitBranchTrue(cg, label);
_right.EmitBranchTrue(cg, label);
return(true);
default:
return(false);
}
}
