private void EmitConditional(FleeILGenerator ilg, IServiceProvider services)
{
Label falseLabel = ilg.DefineLabel();
Label endLabel = ilg.DefineLabel();
// Emit the condition
_myCondition.Emit(ilg, services);
// On false go to the false operand
ilg.EmitBranchFalse(falseLabel);
// Emit the true operand
_myWhenTrue.Emit(ilg, services);
ImplicitConverter.EmitImplicitConvert(_myWhenTrue.ResultType, _myResultType, ilg);
// Jump to end
ilg.EmitBranch(endLabel);
ilg.MarkLabel(falseLabel);
// Emit the false operand
_myWhenFalse.Emit(ilg, services);
ImplicitConverter.EmitImplicitConvert(_myWhenFalse.ResultType, _myResultType, ilg);
// Fall through to end
ilg.MarkLabel(endLabel);
}
/// <summary>
/// Emit a short-circuited logical operation sequence
/// The idea: Store all the leaf operands in a stack with the leftmost at the top and rightmost at the bottom.
/// For each operand, emit it and try to find an end point for when it short-circuits. This means we go up through
/// the stack of operators (ignoring siblings) until we find a different operation (then emit a branch to its right operand)
/// or we reach the root (emit a branch to a true/false).
/// Repeat the process for all operands and then emit the true/false/last operand end cases.
/// </summary>
/// <param name="ilg"></param>
/// <param name="info"></param>
/// <param name="services"></param>
private void EmitLogical(FleeILGenerator ilg, ShortCircuitInfo info, IServiceProvider services)
{
// We always have an end label
Label endLabel = ilg.DefineLabel();
// Populate our data structures
this.PopulateData(info);
// Emit the sequence
EmitLogicalShortCircuit(ilg, info, services);
// Get the last operand
ExpressionElement terminalOperand = (ExpressionElement)info.Operands.Pop();
// Emit it
EmitOperand(terminalOperand, info, ilg, services);
// only 1-3 opcodes, always a short branch
ilg.EmitBranch(endLabel);
// Emit our true/false terminals
EmitTerminals(info, ilg, endLabel);
// Mark the end
ilg.MarkLabel(endLabel);
}
