/// <summary>
/// Determines whether it is safe to move 'expressionBeingMoved' past 'expr'
/// </summary>
bool IsSafeForInlineOver(ILExpression expr, ILExpression expressionBeingMoved)
{
switch (expr.Code)
{
case ILCode.Ldloc:
ILVariable loadedVar = (ILVariable)expr.Operand;
if (numLdloca.GetOrDefault(loadedVar) != 0)
{
// abort, inlining is not possible
return(false);
}
foreach (ILExpression potentialStore in expressionBeingMoved.GetSelfAndChildrenRecursive <ILExpression>())
{
if (potentialStore.Code == ILCode.Stloc && potentialStore.Operand == loadedVar)
{
return(false);
}
}
// the expression is loading a non-forbidden variable
return(true);
case ILCode.Ldloca:
case ILCode.Ldflda:
case ILCode.Ldsflda:
case ILCode.Ldelema:
case ILCode.AddressOf:
case ILCode.ValueOf:
case ILCode.NullableOf:
// address-loading instructions are safe if their arguments are safe
foreach (ILExpression arg in expr.Arguments)
{
if (!IsSafeForInlineOver(arg, expressionBeingMoved))
{
return(false);
}
}
return(true);
default:
// instructions with no side-effects are safe (except for Ldloc and Ldloca which are handled separately)
return(expr.HasNoSideEffects());
}
}
