internal override void Visit(ExceptionHandlerNode node)
{
}
protected static void CreateCatchHandlerEntryBlock(ProgramState state,
ExceptionHandlerNode handlerNode,
CfgNode handlerEntryPredecessor,
Identifier exceptionIdentifier)
{
(var trueBranch, var falseBranch) = CreateExceptionTypeCheckBranchNodes(
state, handlerNode.ExceptionHandler, exceptionIdentifier);
handlerEntryPredecessor.Successors.Add(trueBranch);
handlerEntryPredecessor.Successors.Add(falseBranch);
if (!state.ExceptionHandlerToCatchVarNode.ContainsKey(handlerNode.ExceptionHandler))
{
state.ExceptionHandlerToCatchVarNode[handlerNode.ExceptionHandler] =
CreateLoadCatchVarNode(state, handlerNode.ExceptionHandler);
// The CIL specification dictates that the exception object is on top of
// the stack when the catch handler is entered; the first instruction of
// the catch handler will handle the object pushed onto the stack.
state.PushExpr(new VarExpression(exceptionIdentifier),
new Tptr(Tptr.PtrKind.Pk_pointer,
new Tstruct("System.Object")));
state.PushInstruction(
handlerNode.ExceptionHandler.HandlerStart,
state.ExceptionHandlerToCatchVarNode[handlerNode.ExceptionHandler].node);
}
(var loadCatchVarNode, _) = GetHandlerCatchVarNode(
state, handlerNode.ExceptionHandler);
trueBranch.Successors.Add(loadCatchVarNode);
if (handlerNode.NextCatchBlock != null)
{
// Continues translation with catch handler's first instruction from
// the handler's catch variable load node.
CreateCatchHandlerEntryBlock(state,
handlerNode.NextCatchBlock,
falseBranch,
exceptionIdentifier);
}
// Last catch handler of set; need to route control flow through the false
// exception type-matching node.
else
{
if (handlerNode.FinallyBlock != null)
{
var finallyBranchNode = CreateFinallyExceptionBranchNode(
state, handlerNode.ExceptionHandler);
falseBranch.Successors
.Add(finallyBranchNode);
(var finallyLoadCatchVar, _) = GetHandlerCatchVarNode(
state, handlerNode.FinallyBlock);
finallyBranchNode.Successors.Add(finallyLoadCatchVar);
}
else
{
var returnVariable = new LvarExpression(
new LocalVariable(Identifier.ReturnIdentifier, state.Method));
var retType = state.Method.ReturnType.GetElementType();
var retInstr = new Store(
returnVariable,
new ExnExpression(new VarExpression(exceptionIdentifier)),
Typ.FromTypeReference(retType),
GetHandlerStartLocation(state,
handlerNode.ExceptionHandler));
falseBranch.Instructions
.Add(retInstr);
falseBranch.Successors
.Add(state.ProcDesc.ExceptionSinkNode);
}
}
}
