public bool NeedCombine(ExHandlerInfo other)
{
return(TryStart == other.TryStart &&
TryEnd == other.TryEnd &&
(HandlerType == ExceptionHandlerType.Catch || HandlerType == ExceptionHandlerType.Filter) &&
(other.HandlerType == ExceptionHandlerType.Catch || other.HandlerType == ExceptionHandlerType.Filter));
}
private void BuildInstructions(MethodX metX)
{
Debug.Assert(metX.InstList == null);
if (!metX.Def.HasBody || !metX.Def.Body.HasInstructions)
{
return;
}
IGenericReplacer replacer = new GenericReplacer(metX.DeclType, metX);
var defInstList = metX.Def.Body.Instructions;
int numInsts = defInstList.Count;
InstInfo[] instList = new InstInfo[numInsts];
Dictionary <uint, int> offsetMap = new Dictionary <uint, int>();
List <InstInfo> branchInsts = new List <InstInfo>();
// 构建指令列表
for (int ip = 0; ip < numInsts; ++ip)
{
var defInst = defInstList[ip];
var inst = instList[ip] = new InstInfo();
inst.OpCode = defInst.OpCode;
inst.Operand = defInst.Operand;
inst.Offset = ip;
offsetMap.Add(defInst.Offset, ip);
switch (inst.OpCode.OperandType)
{
case OperandType.InlineBrTarget:
case OperandType.ShortInlineBrTarget:
case OperandType.InlineSwitch:
branchInsts.Add(inst);
break;
default:
ResolveOperand(inst, replacer);
break;
}
}
// 重定向跳转位置
foreach (var inst in branchInsts)
{
if (inst.Operand is Instruction defInst)
{
int target;
inst.Operand = target = offsetMap[defInst.Offset];
instList[target].IsBrTarget = true;
}
else if (inst.Operand is Instruction[] defInsts)
{
int[] insts = new int[defInsts.Length];
for (int i = 0; i < defInsts.Length; ++i)
{
int target;
insts[i] = target = offsetMap[defInsts[i].Offset];
instList[target].IsBrTarget = true;
}
inst.Operand = insts;
}
}
// 展开异常处理信息
if (metX.Def.Body.HasExceptionHandlers)
{
List <Tuple <int, ExHandlerInfo> > sortedHandlers = new List <Tuple <int, ExHandlerInfo> >();
int idx = 0;
foreach (var eh in metX.Def.Body.ExceptionHandlers)
{
ExHandlerInfo info = new ExHandlerInfo();
info.TryStart = offsetMap[eh.TryStart.Offset];
info.TryEnd = offsetMap[eh.TryEnd.Offset];
if (eh.FilterStart != null)
{
info.FilterStart = offsetMap[eh.FilterStart.Offset];
}
else
{
info.FilterStart = -1;
}
info.HandlerStart = offsetMap[eh.HandlerStart.Offset];
if (eh.HandlerEnd != null)
{
info.HandlerEnd = offsetMap[eh.HandlerEnd.Offset];
}
else
{
info.HandlerEnd = instList.Length;
}
if (eh.CatchType != null)
{
info.CatchType = ResolveTypeDefOrRef(eh.CatchType, replacer);
}
info.HandlerType = eh.HandlerType;
sortedHandlers.Add(new Tuple <int, ExHandlerInfo>(idx++, info));
}
// 根据 try 位置排序, 如果相同则根据定义顺序排序
sortedHandlers.Sort((lhs, rhs) =>
{
int cmp = lhs.Item2.TryStart.CompareTo(rhs.Item2.TryStart);
if (cmp == 0)
{
cmp = rhs.Item2.TryEnd.CompareTo(lhs.Item2.TryEnd);
if (cmp == 0)
{
return(lhs.Item1.CompareTo(rhs.Item1));
}
}
return(cmp);
});
// 合并同范围的异常处理器
List <ExHandlerInfo> handlers = new List <ExHandlerInfo>();
ExHandlerInfo headInfo = null;
int count = sortedHandlers.Count;
for (int i = 0; i < count; ++i)
{
ExHandlerInfo currInfo = sortedHandlers[i].Item2;
if (headInfo != null && headInfo.NeedCombine(currInfo))
{
headInfo.CombinedHandlers.Add(currInfo);
}
else
{
headInfo = currInfo;
Debug.Assert(headInfo.CombinedHandlers.Count == 0);
headInfo.CombinedHandlers.Add(headInfo);
handlers.Add(headInfo);
}
instList[currInfo.HandlerOrFilterStart].IsBrTarget = true;
}
metX.ExHandlerList = handlers;
}
metX.InstList = instList;
}