private void EmitListIn(FleeILGenerator ilg, IServiceProvider services, BranchManager bm)
{
var ce = new CompareElement();
var endLabel = bm.FindLabel("endLabel");
var trueTerminal = bm.FindLabel("trueTerminal");
// Cache the operand since we will be comparing against it a lot
var lb = ilg.DeclareLocal(MyOperand.ResultType);
int targetIndex = lb.LocalIndex;
MyOperand.Emit(ilg, services);
Utility.EmitStoreLocal(ilg, targetIndex);
// Wrap our operand in a local shim
var targetShim = new LocalBasedElement(MyOperand, targetIndex);
// Emit the compares
foreach (var argumentElement in MyArguments) {
ce.Initialize(targetShim, argumentElement, LogicalCompareOperation.Equal);
ce.Emit(ilg, services);
EmitBranchToTrueTerminal(ilg, trueTerminal, bm);
}
ilg.Emit(OpCodes.Ldc_I4_0);
ilg.Emit(OpCodes.Br_S, endLabel);
bm.MarkLabel(ilg, trueTerminal);
ilg.MarkLabel(trueTerminal);
ilg.Emit(OpCodes.Ldc_I4_1);
bm.MarkLabel(ilg, endLabel);
ilg.MarkLabel(endLabel);
}
// Emit the end cases for a short-circuit
private static void EmitTerminals(ShortCircuitInfo info, FleeILGenerator ilg, Label endLabel)
{
// Emit the false case if it was used
if (info.Branches.HasLabel(OurFalseTerminalKey) == true)
{
Label falseLabel = info.Branches.FindLabel(OurFalseTerminalKey);
// Mark the label and note its position
ilg.MarkLabel(falseLabel);
MarkBranchTarget(info, falseLabel, ilg);
ilg.Emit(OpCodes.Ldc_I4_0);
// If we also have a true terminal, then skip over it
if (info.Branches.HasLabel(OurTrueTerminalKey) == true)
{
ilg.Emit(OpCodes.Br_S, endLabel);
}
}
// Emit the true case if it was used
if (info.Branches.HasLabel(OurTrueTerminalKey) == true)
{
Label trueLabel = info.Branches.FindLabel(OurTrueTerminalKey);
// Mark the label and note its position
ilg.MarkLabel(trueLabel);
MarkBranchTarget(info, trueLabel, ilg);
ilg.Emit(OpCodes.Ldc_I4_1);
}
}
// 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.
private void EmitLogical(FleeILGenerator ilg, ShortCircuitInfo info, IServiceProvider services)
{
// We always have an end label
info.Branches.GetLabel(OurEndLabelKey, ilg);
// 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);
// And jump to the end
Label endLabel = info.Branches.FindLabel(OurEndLabelKey);
ilg.Emit(OpCodes.Br_S, endLabel);
// Emit our true/false terminals
EmitTerminals(info, ilg, endLabel);
// Mark the end
ilg.MarkLabel(endLabel);
}
private static void EmitOperand(ExpressionElement operand, ShortCircuitInfo info, FleeILGenerator ilg, IServiceProvider services)
{
// Is this operand the target of a label?
if (info.Branches.HasLabel(operand) == true)
{
// Yes, so mark it
Label leftLabel = info.Branches.FindLabel(operand);
ilg.MarkLabel(leftLabel);
// Note the label's position
MarkBranchTarget(info, leftLabel, ilg);
}
// Emit the operand
operand.Emit(ilg, services);
}
private void EmitConditional(FleeILGenerator ilg, IServiceProvider services, BranchManager bm)
{
var falseLabel = bm.FindLabel("falseLabel");
var endLabel = bm.FindLabel("endLabel");
// Emit the condition
MyCondition.Emit(ilg, services);
// On false go to the false operand
if (ilg.IsTemp == true) {
bm.AddBranch(ilg, falseLabel);
ilg.Emit(OpCodes.Brfalse_S, falseLabel);
} else if (bm.IsLongBranch(ilg, falseLabel) == false) {
ilg.Emit(OpCodes.Brfalse_S, falseLabel);
} else {
ilg.Emit(OpCodes.Brfalse, falseLabel);
}
// Emit the true operand
MyWhenTrue.Emit(ilg, services);
ImplicitConverter.EmitImplicitConvert(MyWhenTrue.ResultType, MyResultType, ilg);
// Jump to end
if (ilg.IsTemp == true) {
bm.AddBranch(ilg, endLabel);
ilg.Emit(OpCodes.Br_S, endLabel);
} else if (bm.IsLongBranch(ilg, endLabel) == false) {
ilg.Emit(OpCodes.Br_S, endLabel);
} else {
ilg.Emit(OpCodes.Br, endLabel);
}
bm.MarkLabel(ilg, falseLabel);
ilg.MarkLabel(falseLabel);
// Emit the false operand
MyWhenFalse.Emit(ilg, services);
ImplicitConverter.EmitImplicitConvert(MyWhenFalse.ResultType, MyResultType, ilg);
// Fall through to end
bm.MarkLabel(ilg, endLabel);
ilg.MarkLabel(endLabel);
}
