internal static BoundStatement Rewrite(
BoundStatement body,
MethodSymbol method,
int methodOrdinal,
ArrayBuilder <StateMachineStateDebugInfo> stateMachineStateDebugInfoBuilder,
VariableSlotAllocator slotAllocatorOpt,
TypeCompilationState compilationState,
BindingDiagnosticBag diagnostics,
out IteratorStateMachine stateMachineType)
{
TypeWithAnnotations elementType = method.IteratorElementTypeWithAnnotations;
if (elementType.IsDefault || method.IsAsync)
{
stateMachineType = null;
return(body);
}
// Figure out what kind of iterator we are generating.
bool isEnumerable;
switch (method.ReturnType.OriginalDefinition.SpecialType)
{
case SpecialType.System_Collections_IEnumerable:
case SpecialType.System_Collections_Generic_IEnumerable_T:
isEnumerable = true;
break;
case SpecialType.System_Collections_IEnumerator:
case SpecialType.System_Collections_Generic_IEnumerator_T:
isEnumerable = false;
break;
default:
throw ExceptionUtilities.UnexpectedValue(method.ReturnType.OriginalDefinition.SpecialType);
}
stateMachineType = new IteratorStateMachine(slotAllocatorOpt, compilationState, method, methodOrdinal, isEnumerable, elementType);
compilationState.ModuleBuilderOpt.CompilationState.SetStateMachineType(method, stateMachineType);
var rewriter = new IteratorRewriter(body, method, isEnumerable, stateMachineType, stateMachineStateDebugInfoBuilder, slotAllocatorOpt, compilationState, diagnostics);
if (!rewriter.VerifyPresenceOfRequiredAPIs())
{
return(body);
}
return(rewriter.Rewrite());
}
/// <summary>
/// Rewrite an iterator method into a state machine class.
/// </summary>
internal static BoundStatement Rewrite(
BoundStatement body,
MethodSymbol method,
int methodOrdinal,
VariableSlotAllocator slotAllocatorOpt,
TypeCompilationState compilationState,
DiagnosticBag diagnostics,
out IteratorStateMachine stateMachineType)
{
TypeSymbol elementType = method.IteratorElementType;
if ((object)elementType == null)
{
stateMachineType = null;
return body;
}
// Figure out what kind of iterator we are generating.
bool isEnumerable;
switch (method.ReturnType.OriginalDefinition.SpecialType)
{
case SpecialType.System_Collections_IEnumerable:
case SpecialType.System_Collections_Generic_IEnumerable_T:
isEnumerable = true;
break;
case SpecialType.System_Collections_IEnumerator:
case SpecialType.System_Collections_Generic_IEnumerator_T:
isEnumerable = false;
break;
default:
throw ExceptionUtilities.UnexpectedValue(method.ReturnType.OriginalDefinition.SpecialType);
}
stateMachineType = new IteratorStateMachine(slotAllocatorOpt, compilationState, method, methodOrdinal, isEnumerable, elementType);
compilationState.ModuleBuilderOpt.CompilationState.SetStateMachineType(method, stateMachineType);
var rewriter = new IteratorRewriter(body, method, isEnumerable, stateMachineType, slotAllocatorOpt, compilationState, diagnostics);
if (!rewriter.VerifyPresenceOfRequiredAPIs())
{
return body;
}
return rewriter.Rewrite();
}
