private void InferBasicBlocks()
{
List <BasicBlock <Ti> > bbs = new List <BasicBlock <Ti> >();
int curIndex = 0;
do
{
int startIndex = curIndex;
int lastIndex = curIndex;
while (!IsEndOfBB(lastIndex))
{
++lastIndex;
}
BasicBlock <Ti> bb = CreateBasicBlock(startIndex, lastIndex);
if (curIndex == Instructions.Count - 1)
{
bb.IsExitBlock = true;
}
else
{
IEnumerable <int> targets;
EBranchBehavior bbh = InstructionInfo.IsBranch(Instructions[lastIndex], out targets);
if (bbh == EBranchBehavior.Switch)
{
// Special case: evil switch instructions
bb.IsSwitch = true;
}
}
bbs.Add(bb);
curIndex = lastIndex + 1;
} while (curIndex < Instructions.Count);
BasicBlocks = bbs.ToArray();
}
private void AnalyzeBranches()
{
MarkAsBranchTarget(Instructions[_entryPoint]);
Ti[] term = new Ti[] { _marshal };
MarkAsBranch(_marshal);
MarkAsBranchTarget(_marshal);
foreach (Ti ili in Instructions)
{
if (_exitPoints != null && _exitPoints.Contains(ili.Index))
{
_successors[ili.Index] = term;
MarkAsBranch(ili);
}
else if (ili.Index == _marshal.Index)
{
_successors[ili.Index] = new Ti[0];
}
else
{
IEnumerable <int> targets;
EBranchBehavior bb = InstructionInfo.IsBranch(ili, out targets);
bool includeNext = false;
bool isBranch = false;
bool isTerm = false;
switch (bb)
{
case EBranchBehavior.NoBranch:
includeNext = true;
isBranch = false;
isTerm = false;
break;
case EBranchBehavior.UBranch:
includeNext = false;
isBranch = true;
isTerm = false;
break;
case EBranchBehavior.CBranch:
includeNext = true;
isBranch = true;
isTerm = false;
break;
case EBranchBehavior.Return:
case EBranchBehavior.Throw:
includeNext = false;
isBranch = true;
isTerm = true;
break;
case EBranchBehavior.Switch:
includeNext = true;
isBranch = true;
isTerm = false;
break;
default:
throw new NotImplementedException();
}
if (isBranch)
{
MarkAsBranch(ili);
}
foreach (int target in targets)
{
MarkAsBranchTarget(Instructions[target]);
}
if (isTerm && ili.Index < Instructions.Count - 1)
{
_successors[ili.Index] = term;
}
else if (includeNext)
{
List <Ti> succs = new List <Ti>();
succs.Add(Instructions[ili.Index + 1]);
succs.AddRange(targets.Select(t => Instructions[t]));
_successors[ili.Index] = succs.ToArray();
}
else
{
_successors[ili.Index] = targets.Select(t => Instructions[t]).ToArray();
}
}
}
}
