JumpTable BuildJumpTable(Method method)
{
var jumpTable = new JumpTable();
int gotoCounter = 0;
int ifCounter = 0;
int switchCounter = 0;
foreach (var opcode in method.GetInstructions())
{
switch (opcode.Instruction)
{
case Instructions.Goto:
case Instructions.Goto16:
case Instructions.Goto32:
var gotoOpCode = (dynamic)opcode;
jumpTable.AddTarget(gotoOpCode.OpCodeOffset, gotoOpCode.GetTargetAddress(), "goto_", ref gotoCounter);
break;
case Instructions.PackedSwitch:
case Instructions.SparseSwitch:
dynamic switchOpCode = opcode;
foreach (var switchTarget in switchOpCode.GetTargetAddresses())
{
jumpTable.AddTarget(switchOpCode.OpCodeOffset, switchTarget, "switch_", ref switchCounter);
}
break;
case Instructions.IfEq:
case Instructions.IfNe:
case Instructions.IfLt:
case Instructions.IfGe:
case Instructions.IfGt:
case Instructions.IfLe:
case Instructions.IfEqz:
case Instructions.IfNez:
case Instructions.IfLtz:
case Instructions.IfGez:
case Instructions.IfGtz:
case Instructions.IfLez:
dynamic ifOpCode = opcode;
jumpTable.AddTarget(ifOpCode.OpCodeOffset, ifOpCode.GetTargetAddress(), "if_", ref ifCounter);
break;
}
}
var catchCounter = 0;
if (method.TryCatchBlocks != null)
{
foreach (var tryBlock in method.TryCatchBlocks)
{
foreach (var catchBlock in tryBlock.Handlers)
{
jumpTable.AddHandler(catchBlock, "catch_", ref catchCounter);
}
}
}
return(jumpTable);
}
