public List<ILNode> ConvertToAst(List<Instruction> body, IEnumerable<ExceptionHandler> ehs)
{
List<ILNode> ast = new List<ILNode>();
while (ehs.Any()) {
ILTryCatchBlock tryCatchBlock = new ILTryCatchBlock();
// Find the first and widest scope
int tryStart = ehs.Min(eh => eh.TryStart.Offset);
int tryEnd = ehs.Where(eh => eh.TryStart.Offset == tryStart).Max(eh => eh.TryEnd.Offset);
var handlers = ehs.Where(eh => eh.TryStart.Offset == tryStart && eh.TryEnd.Offset == tryEnd).ToList();
// Cut all instructions up to the try block
{
int tryStartIdx;
for (tryStartIdx = 0; body[tryStartIdx].Offset != tryStart; tryStartIdx++);
ast.AddRange(ConvertToAst(body.CutRange(0, tryStartIdx)));
}
// Cut the try block
{
List<ExceptionHandler> nestedEHs = ehs.Where(eh => (tryStart <= eh.TryStart.Offset && eh.TryEnd.Offset < tryEnd) || (tryStart < eh.TryStart.Offset && eh.TryEnd.Offset <= tryEnd)).ToList();
int tryEndIdx;
for (tryEndIdx = 0; tryEndIdx < body.Count && body[tryEndIdx].Offset != tryEnd; tryEndIdx++);
tryCatchBlock.TryBlock = ConvertToAst(body.CutRange(0, tryEndIdx), nestedEHs);
}
// Cut all handlers
tryCatchBlock.CatchBlocks = new List<ILTryCatchBlock.CatchBlock>();
foreach(ExceptionHandler eh in handlers) {
int start;
for (start = 0; body[start] != eh.HandlerStart; start++);
int end;
for (end = 0; body[end] != eh.HandlerEnd; end++);
int count = end - start;
List<ExceptionHandler> nestedEHs = ehs.Where(e => (start <= e.TryStart.Offset && e.TryEnd.Offset < end) || (start < e.TryStart.Offset && e.TryEnd.Offset <= end)).ToList();
List<ILNode> handlerAst = ConvertToAst(body.CutRange(start, count), nestedEHs);
if (eh.HandlerType == ExceptionHandlerType.Catch) {
tryCatchBlock.CatchBlocks.Add(new ILTryCatchBlock.CatchBlock() {
ExceptionType = eh.CatchType,
Body = handlerAst
});
} else if (eh.HandlerType == ExceptionHandlerType.Finally) {
tryCatchBlock.FinallyBlock = handlerAst;
} else {
// TODO
}
}
ehs = ehs.Where(eh => eh.TryStart.Offset > tryEnd).ToList();
ast.Add(tryCatchBlock);
}
// Add whatever is left
ast.AddRange(ConvertToAst(body));
return ast;
}
List<ILNode> ConvertToAst(List<ByteCode> body, HashSet<ExceptionHandler> ehs)
{
List<ILNode> ast = new List<ILNode>();
while (ehs.Any()) {
ILTryCatchBlock tryCatchBlock = new ILTryCatchBlock();
// Find the first and widest scope
int tryStart = ehs.Min(eh => eh.TryStart.Offset);
int tryEnd = ehs.Where(eh => eh.TryStart.Offset == tryStart).Max(eh => eh.TryEnd.Offset);
var handlers = ehs.Where(eh => eh.TryStart.Offset == tryStart && eh.TryEnd.Offset == tryEnd).ToList();
// Cut all instructions up to the try block
{
int tryStartIdx;
for (tryStartIdx = 0; body[tryStartIdx].Offset != tryStart; tryStartIdx++);
ast.AddRange(ConvertToAst(body.CutRange(0, tryStartIdx)));
}
// Cut the try block
{
HashSet<ExceptionHandler> nestedEHs = new HashSet<ExceptionHandler>(ehs.Where(eh => (tryStart <= eh.TryStart.Offset && eh.TryEnd.Offset < tryEnd) || (tryStart < eh.TryStart.Offset && eh.TryEnd.Offset <= tryEnd)));
ehs.ExceptWith(nestedEHs);
int tryEndIdx;
for (tryEndIdx = 0; tryEndIdx < body.Count && body[tryEndIdx].Offset != tryEnd; tryEndIdx++);
tryCatchBlock.TryBlock = new ILBlock(ConvertToAst(body.CutRange(0, tryEndIdx), nestedEHs));
}
// Cut all handlers
tryCatchBlock.CatchBlocks = new List<ILTryCatchBlock.CatchBlock>();
foreach(ExceptionHandler eh in handlers) {
int startIndex;
for (startIndex = 0; body[startIndex].Offset != eh.HandlerStart.Offset; startIndex++);
int endInclusiveIndex;
// Note that the end(exclusiove) instruction may not necessarly be in our body
for (endInclusiveIndex = 0; body[endInclusiveIndex].Next.Offset != eh.HandlerEnd.Offset; endInclusiveIndex++);
int count = 1 + endInclusiveIndex - startIndex;
HashSet<ExceptionHandler> nestedEHs = new HashSet<ExceptionHandler>(ehs.Where(e => (eh.HandlerStart.Offset <= e.TryStart.Offset && e.TryEnd.Offset < eh.HandlerEnd.Offset) || (eh.HandlerStart.Offset < e.TryStart.Offset && e.TryEnd.Offset <= eh.HandlerEnd.Offset)));
ehs.ExceptWith(nestedEHs);
List<ILNode> handlerAst = ConvertToAst(body.CutRange(startIndex, count), nestedEHs);
if (eh.HandlerType == ExceptionHandlerType.Catch) {
tryCatchBlock.CatchBlocks.Add(new ILTryCatchBlock.CatchBlock() {
ExceptionType = eh.CatchType,
Body = handlerAst
});
} else if (eh.HandlerType == ExceptionHandlerType.Finally) {
tryCatchBlock.FinallyBlock = new ILBlock(handlerAst);
} else {
// TODO
}
}
ehs.ExceptWith(handlers);
ast.Add(tryCatchBlock);
}
// Add whatever is left
ast.AddRange(ConvertToAst(body));
return ast;
}