// insert the given new target basic block (given by start and end block) between the given conditional branch to manipulate
public void insertBasicBlockBetweenBranch(ConditionalBranchTarget branchToManipulate, bool manipulateTakenBranch, BasicBlock newTargetStart, BasicBlock newTargetEnd, NoBranchTarget exitBranch) {
// get the basic block from that the branch is taken and the basic block to that the branch is taken
BasicBlock introBasicBlock = branchToManipulate.sourceBasicBlock;
BasicBlock outroBasicBlock = null;
// manipulate the correct branch
if (manipulateTakenBranch) {
outroBasicBlock = branchToManipulate.takenTarget;
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.takenTarget, newTargetStart, newTargetEnd, exitBranch, ref exitBranch.takenTarget);
}
else {
outroBasicBlock = branchToManipulate.notTakenTarget;
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.notTakenTarget, newTargetStart, newTargetEnd, exitBranch, ref exitBranch.takenTarget);
}
}
// this function splits a basic block on the given index
public void splitBasicBlock(BasicBlock firstPartBB, int splitIndex) {
// check if the index is out of bounds
if (splitIndex >= firstPartBB.operations.Count()) {
throw new ArgumentException("Index is equal or greater than existing basic block operations.");
}
// check if there are at least 2 operations inside the basic block to split
if (firstPartBB.operations.Count() < 2) {
throw new ArgumentException("Too few operations in basic block for splitting.");
}
// create the new basic block that will become the second part of the basic block to split
BasicBlock secondPartBB = new BasicBlock();
// move the exit basic blocks to the new created basic block
// and make the new created basic block the exit of the splitted one
secondPartBB.exitBranch = firstPartBB.exitBranch;
secondPartBB.exitBranch.sourceBasicBlock = secondPartBB;
NoBranchTarget tempExitBranch = new NoBranchTarget();
tempExitBranch.takenTarget = secondPartBB;
tempExitBranch.sourceBasicBlock = firstPartBB;
firstPartBB.exitBranch = tempExitBranch;
// add splitted basic block branch
// to the entries of the new basic block
secondPartBB.entryBranches.Add(tempExitBranch);
// distribute the instructions to the basic blocks
List<IOperation> previousOperations = new List<IOperation>();
List<IOperation> nextOperations = new List<IOperation>();
for (int operationIdx = 0; operationIdx < firstPartBB.operations.Count(); operationIdx++) {
if (operationIdx < splitIndex) {
previousOperations.Add(firstPartBB.operations.ElementAt(operationIdx));
}
else {
nextOperations.Add(firstPartBB.operations.ElementAt(operationIdx));
}
}
firstPartBB.operations = previousOperations;
secondPartBB.operations = nextOperations;
// add a semantic id to the new basic block
if (firstPartBB.semanticId == -1) {
secondPartBB.semanticId = -1;
}
else {
int highestSemanticId = 0;
foreach (BasicBlock tempBB in methodCfg.basicBlocks) {
if (tempBB.semanticId > highestSemanticId) {
highestSemanticId = tempBB.semanticId;
}
}
secondPartBB.semanticId = highestSemanticId + 1;
}
// add new basic block to the cfg
methodCfg.basicBlocks.Add(secondPartBB);
}
// insert the given new target basic block between the given conditional branch to manipulate
public void insertBasicBlockBetweenBranch(NoBranchTarget branchToManipulate, BasicBlock newTarget, SwitchBranchTarget exitBranch, int switchTakenBranchIdx) {
// get the basic block from that the branch is taken and the basic block to that the branch is taken
BasicBlock introBasicBlock = branchToManipulate.sourceBasicBlock;
BasicBlock outroBasicBlock = branchToManipulate.takenTarget;
BasicBlock tempTakenTarget = null;
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.takenTarget, newTarget, newTarget, exitBranch, ref tempTakenTarget);
// fill switch taken branch list with null when index is out of range
while (exitBranch.takenTarget.Count() <= switchTakenBranchIdx) {
exitBranch.takenTarget.Add(null);
}
exitBranch.takenTarget[switchTakenBranchIdx] = tempTakenTarget;
}
// insert the given new target basic block (given by start and end block) between the given unconditional branch to manipulate
public void insertBasicBlockBetweenBranch(UnconditionalBranchTarget branchToManipulate, BasicBlock newTargetStart, BasicBlock newTargetEnd, NoBranchTarget exitBranch) {
// get the basic block from that the branch is taken and the basic block to that the branch is taken
BasicBlock introBasicBlock = branchToManipulate.sourceBasicBlock;
BasicBlock outroBasicBlock = branchToManipulate.takenTarget;
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.takenTarget, newTargetStart, newTargetEnd, exitBranch, ref exitBranch.takenTarget);
}
// build recursively the cfg of the given operations
private void buildRecursivelyCfg(MethodCfg methodCfg, IEnumerable<IOperation> operations, int currentIdx, IBranchTarget entryBranch, ref BasicBlock currentBasicBlock) {
// check if a new basic block has to be created
for (int bbIdx = 0; bbIdx < methodCfg.basicBlocks.Count(); bbIdx++) {
// check if the current index points into an existing basic block
// => split basic block
BasicBlock tempBB = methodCfg.basicBlocks.ElementAt(bbIdx);
if (tempBB.startIdx < currentIdx && tempBB.endIdx >= currentIdx) {
// create new basic block which will be the second half of the found one
BasicBlock newBasicBlock = new BasicBlock(this.semanticId);
this.semanticId++;
newBasicBlock.startIdx = currentIdx;
newBasicBlock.endIdx = tempBB.endIdx;
tempBB.endIdx = currentIdx - 1;
// move the exit basic blocks to the new created basic block
// and make the new created basic block the exit of the splitted one
newBasicBlock.exitBranch = tempBB.exitBranch;
newBasicBlock.exitBranch.sourceBasicBlock = newBasicBlock;
NoBranchTarget tempExitBranch = new NoBranchTarget();
tempExitBranch.takenTarget = newBasicBlock;
tempExitBranch.sourceBasicBlock = tempBB;
tempBB.exitBranch = tempExitBranch;
// set the current basic block to the new created basic block
currentBasicBlock = newBasicBlock;
// add splitted basic block branch and basic block branch that leads to this split
// to the entries of the new one
newBasicBlock.entryBranches.Add(entryBranch);
newBasicBlock.entryBranches.Add(tempExitBranch);
// distribute the instructions to the basic blocks
List<IOperation> previousOperations = new List<IOperation>();
List<IOperation> nextOperations = new List<IOperation>();
for (int operationIdx = 0; (operationIdx + tempBB.startIdx) <= newBasicBlock.endIdx; operationIdx++) {
if ((operationIdx + tempBB.startIdx) < currentIdx) {
previousOperations.Add(tempBB.operations.ElementAt(operationIdx));
}
else {
nextOperations.Add(tempBB.operations.ElementAt(operationIdx));
}
}
tempBB.operations = previousOperations;
newBasicBlock.operations = nextOperations;
// add new basic block to the cfg
methodCfg.basicBlocks.Add(newBasicBlock);
return;
}
// if the current index of the operation points to the start index of an existing basic block
// => update entry branches
else if (tempBB.startIdx == currentIdx && entryBranch != null && currentBasicBlock != null) {
tempBB.entryBranches.Add(entryBranch);
// set the found basic block as the current basic block
currentBasicBlock = tempBB;
return;
}
// if the current index of the operation points to the start index of an existing basic block, has no entry branch
// and is not the first instruction
// set the current basic block to the found one
else if (currentIdx != 0 && tempBB.startIdx == currentIdx && currentBasicBlock != null) {
// set the found basic block as the current basic block
currentBasicBlock = tempBB;
return;
}
}
// set index of current basic block and add it to the cfg
currentBasicBlock.startIdx = currentIdx;
methodCfg.basicBlocks.Add(currentBasicBlock);
// check if the basic block was jumped to from another basic block
// => update entry branches
if (entryBranch != null) {
currentBasicBlock.entryBranches.Add(entryBranch);
}
// parse every instruction to find branches etc
for (int idx = currentIdx; idx < operations.Count(); idx++) {
// check if the current instruction is the start instruction of an already existing basic block (except the current basic block)
// => add the current basic block to the list of entry basic blocks, the found basic block to the list of exit basic blocks and set the index
for (int bbIdx = 0; bbIdx < methodCfg.basicBlocks.Count(); bbIdx++) {
BasicBlock tempBB = methodCfg.basicBlocks.ElementAt(bbIdx);
if (tempBB.startIdx == idx && tempBB != currentBasicBlock) {
currentBasicBlock.endIdx = idx - 1;
// create new exit branch and add it
NoBranchTarget currentExitBranch = new NoBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.takenTarget = tempBB;
currentBasicBlock.exitBranch = currentExitBranch;
// add current exit branch as entry for the found one
tempBB.entryBranches.Add(currentExitBranch);
return;
}
}
// add current instruction to the basic block
var operation = operations.ElementAt(idx);
currentBasicBlock.operations.Add(operation);
// check for special instructions like branches
switch (operation.OperationCode) {
// conditional branch instructions
case OperationCode.Beq:
case OperationCode.Bge:
case OperationCode.Bge_Un:
case OperationCode.Bgt:
case OperationCode.Bgt_Un:
case OperationCode.Ble:
case OperationCode.Ble_Un:
case OperationCode.Blt:
case OperationCode.Blt_Un:
case OperationCode.Bne_Un:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Beq_S:
case OperationCode.Bge_S:
case OperationCode.Bge_Un_S:
case OperationCode.Bgt_S:
case OperationCode.Bgt_Un_S:
case OperationCode.Ble_S:
case OperationCode.Ble_Un_S:
case OperationCode.Blt_S:
case OperationCode.Blt_Un_S:
case OperationCode.Bne_Un_S:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue_S: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// calculate the target index of the branch
int branchTargetIdx = 0;
uint branchTargetOffset;
// do operation value can be of type long which can not be casted in this way
if (operation.Value is long) {
branchTargetOffset = Convert.ToUInt32(operation.Value);
}
else {
branchTargetOffset = (uint)operation.Value;
}
while (true) {
if (operations.ElementAt(branchTargetIdx).Offset == branchTargetOffset) {
break;
}
else if (operations.ElementAt(branchTargetIdx).Offset > branchTargetOffset) {
throw new ArgumentException("Could not find target off branch.");
}
branchTargetIdx++;
}
// create new exit branch object
ConditionalBranchTarget currentExitBranch = new ConditionalBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.notTakenTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentExitBranch.takenTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentBasicBlock.exitBranch = currentExitBranch;
// start two new basic blocks from this branch on and end current execution
this.buildRecursivelyCfg(methodCfg, operations, idx + 1, currentExitBranch, ref currentExitBranch.notTakenTarget);
this.buildRecursivelyCfg(methodCfg, operations, branchTargetIdx, currentExitBranch, ref currentExitBranch.takenTarget);
return;
}
// unconditional branch instructions
case OperationCode.Br:
case OperationCode.Br_S: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// calculate the target index of the branch
int branchTargetIdx = 0;
uint branchTargetOffset = (uint)operation.Value;
while (true) {
if (operations.ElementAt(branchTargetIdx).Offset == branchTargetOffset) {
break;
}
else if (operations.ElementAt(branchTargetIdx).Offset > branchTargetOffset) {
throw new ArgumentException("Could not find target off branch.");
}
branchTargetIdx++;
}
// create new exit branch object
UnconditionalBranchTarget currentExitBranch = new UnconditionalBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.takenTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentBasicBlock.exitBranch = currentExitBranch;
// start one new basic block from this branch on and end current execution
this.buildRecursivelyCfg(methodCfg, operations, branchTargetIdx, currentExitBranch, ref currentExitBranch.takenTarget);
return;
}
// exit operation
case OperationCode.Ret: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// create new exit branch object
ExitBranchTarget currentExitBranch = new ExitBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentBasicBlock.exitBranch = currentExitBranch;
// end current execution
return;
}
// operations that exit the current function/control flow
case OperationCode.Throw: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// create new exit branch object
ThrowBranchTarget currentExitBranch = new ThrowBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentBasicBlock.exitBranch = currentExitBranch;
// start a new basic block if this was not the last instruction of the method
// (needed because some control flows that are reached via throw are not found without it)
if ((idx + 1) < operations.Count()) {
BasicBlock newStartBasicBlock = new BasicBlock(this.semanticId);
this.semanticId++;
this.buildRecursivelyCfg(methodCfg, operations, idx + 1, null, ref newStartBasicBlock);
}
// end current execution
return;
}
// switch instruction (has a variable set of jump targets)
case OperationCode.Switch: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// create new exit branch object
SwitchBranchTarget currentExitBranch = new SwitchBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.notTakenTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentBasicBlock.exitBranch = currentExitBranch;
// calculate the target index of all switch branches
int counter = 0;
foreach (uint branchTargetOffset in (uint[])operation.Value) {
int branchTargetIdx = 0;
while (true) {
if (operations.ElementAt(branchTargetIdx).Offset == branchTargetOffset) {
break;
}
else if (operations.ElementAt(branchTargetIdx).Offset > branchTargetOffset) {
throw new ArgumentException("Could not find target off branch.");
}
branchTargetIdx++;
}
// start a new basic block from this branch on
BasicBlock tempNextBasicBlock = new BasicBlock(this.semanticId);
this.semanticId++;
this.buildRecursivelyCfg(methodCfg, operations, branchTargetIdx, currentExitBranch, ref tempNextBasicBlock);
// add new basic block to branch targets
currentExitBranch.takenTarget.Add(tempNextBasicBlock);
counter++;
}
// start a new basic block directly after the switch instruction and end current execution
this.buildRecursivelyCfg(methodCfg, operations, idx + 1, currentExitBranch, ref currentExitBranch.notTakenTarget);
return;
}
// exception handler beginning or end (end of try block or catch block)
case OperationCode.Leave:
case OperationCode.Leave_S: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// calculate the target index of the branch
int branchTargetIdx = 0;
uint branchTargetOffset = (uint)operation.Value;
while (true) {
if (operations.ElementAt(branchTargetIdx).Offset == branchTargetOffset) {
break;
}
else if (operations.ElementAt(branchTargetIdx).Offset > branchTargetOffset) {
throw new ArgumentException("Could not find target off branch.");
}
branchTargetIdx++;
}
// create new exit branch object
ExceptionBranchTarget currentExitBranch = new ExceptionBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.exceptionTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentExitBranch.exitTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentBasicBlock.exitBranch = currentExitBranch;
// start two new basic blocks from this branch on and end current execution
this.buildRecursivelyCfg(methodCfg, operations, idx + 1, currentExitBranch, ref currentExitBranch.exceptionTarget);
this.buildRecursivelyCfg(methodCfg, operations, branchTargetIdx, currentExitBranch, ref currentExitBranch.exitTarget);
return;
}
// create a virtual basic block at the end of a catch/finally handler
case OperationCode.Rethrow:
case OperationCode.Endfinally: {
// the current basic block ends here
currentBasicBlock.endIdx = idx;
// create new exit branch object
NoBranchTarget currentExitBranch = new NoBranchTarget();
currentExitBranch.sourceBasicBlock = currentBasicBlock;
currentExitBranch.takenTarget = new BasicBlock(this.semanticId);
this.semanticId++;
currentBasicBlock.exitBranch = currentExitBranch;
// start a new basic block from this branch on and end current execution
this.buildRecursivelyCfg(methodCfg, operations, idx + 1, currentExitBranch, ref currentExitBranch.takenTarget);
return;
}
default:
break;
}
}
}
// insert the given new target basic block between the given no branch to manipulate
public void insertBasicBlockBetweenBranch(NoBranchTarget branchToManipulate, BasicBlock newTarget, ConditionalBranchTarget exitBranch, bool useTakenBranch) {
// get the basic block from that the branch is taken and the basic block to that the branch is taken
BasicBlock introBasicBlock = branchToManipulate.sourceBasicBlock;
BasicBlock outroBasicBlock = branchToManipulate.takenTarget;
// check wether to use the taken or not taken part of the exit branch
if (useTakenBranch) {
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.takenTarget, newTarget, newTarget, exitBranch, ref exitBranch.takenTarget);
}
else {
this.insertBasicBlockBetweenBranch(introBasicBlock, outroBasicBlock, branchToManipulate, ref branchToManipulate.takenTarget, newTarget, newTarget, exitBranch, ref exitBranch.notTakenTarget);
}
}
// this constructor copies the given source method cfg and all its elements
// NOTE: it ignores the transformation metadata
public MethodCfg(MethodCfg sourceMethodCfg) {
// copy link to the method
this.method = sourceMethodCfg.method;
// generate a list of already processed basic blocks
List<BasicBlock> processedBasicBlocks = new List<BasicBlock>();
// set start basic block of the CFG as already processed
processedBasicBlocks.Add(sourceMethodCfg.startBasicBlock);
// create copy of start basic block
BasicBlock copiedStartBasicBlock = new BasicBlock();
this.startBasicBlock = copiedStartBasicBlock;
this.basicBlocks.Add(copiedStartBasicBlock);
// copy simple values
copiedStartBasicBlock.id = sourceMethodCfg.startBasicBlock.id;
copiedStartBasicBlock.semanticId = sourceMethodCfg.startBasicBlock.semanticId;
copiedStartBasicBlock.startIdx = sourceMethodCfg.startBasicBlock.startIdx;
copiedStartBasicBlock.endIdx = sourceMethodCfg.startBasicBlock.endIdx;
// copy all operations of the basic block
foreach (IOperation operation in sourceMethodCfg.startBasicBlock.operations) {
InternalOperation copiedOperation = new InternalOperation();
copiedOperation.OperationCode = operation.OperationCode;
copiedOperation.Value = operation.Value;
copiedOperation.Offset = operation.Offset;
copiedOperation.Location = operation.Location;
copiedStartBasicBlock.operations.Add(copiedOperation);
}
// process rest of the cfg and copy the exit branch
if ((sourceMethodCfg.startBasicBlock.exitBranch as NoBranchTarget) != null) {
NoBranchTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as NoBranchTarget);
// create a copied exit branch
NoBranchTarget copiedExitBranch = new NoBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as UnconditionalBranchTarget != null) {
UnconditionalBranchTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as UnconditionalBranchTarget);
// create a copied exit branch
UnconditionalBranchTarget copiedExitBranch = new UnconditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as ConditionalBranchTarget != null) {
ConditionalBranchTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as ConditionalBranchTarget);
// create a copied exit branch
ConditionalBranchTarget copiedExitBranch = new ConditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch, true);
// process branch and next basic block
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.notTakenTarget, ref nextCopiedBasicBlock, copiedExitBranch, false);
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as SwitchBranchTarget != null) {
SwitchBranchTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as SwitchBranchTarget);
// create a copied exit branch
SwitchBranchTarget copiedExitBranch = new SwitchBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// first process not taken branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.notTakenTarget, ref nextCopiedBasicBlock, copiedExitBranch, -1);
// process all taken branches and next basic blocks
for (int idx = 0; idx < exitBranch.takenTarget.Count(); idx++) {
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget.ElementAt(idx), ref nextCopiedBasicBlock, copiedExitBranch, idx);
}
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as ExitBranchTarget != null) {
// create a copied exit branch
ExitBranchTarget copiedExitBranch = new ExitBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as ThrowBranchTarget != null) {
// create a copied exit branch
ThrowBranchTarget copiedExitBranch = new ThrowBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as TryBlockTarget != null) {
TryBlockTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as TryBlockTarget);
// create a copied exit branch
TryBlockTarget copiedExitBranch = new TryBlockTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceMethodCfg.startBasicBlock.exitBranch as ExceptionBranchTarget != null) {
ExceptionBranchTarget exitBranch = (sourceMethodCfg.startBasicBlock.exitBranch as ExceptionBranchTarget);
// create a copied exit branch
ExceptionBranchTarget copiedExitBranch = new ExceptionBranchTarget();
copiedExitBranch.sourceBasicBlock = copiedStartBasicBlock;
copiedStartBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.exceptionTarget, ref nextCopiedBasicBlock, copiedExitBranch, true);
// process branch and next basic block
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.exitTarget, ref nextCopiedBasicBlock, copiedExitBranch, false);
}
else {
throw new ArgumentException("Do not know how to handle exit branch.");
}
// copy all try blocks
foreach (TryBlock sourceTryBlock in sourceMethodCfg.startBasicBlock.tryBlocks) {
TryBlock copiedTryBlock = new TryBlock();
copiedTryBlock.exceptionHandler = sourceTryBlock.exceptionHandler;
copiedTryBlock.firstBasicBlockOfTryBlock = sourceTryBlock.firstBasicBlockOfTryBlock;
copiedTryBlock.lastBasicBlockOfTryBlock = sourceTryBlock.lastBasicBlockOfTryBlock;
copiedStartBasicBlock.tryBlocks.Add(copiedTryBlock);
}
// copy all handler blocks
foreach (HandlerBlock sourceHandlerBlock in sourceMethodCfg.startBasicBlock.handlerBlocks) {
HandlerBlock copiedHandlerBlock = new HandlerBlock();
copiedHandlerBlock.exceptionHandler = sourceHandlerBlock.exceptionHandler;
copiedHandlerBlock.typeOfHandler = sourceHandlerBlock.typeOfHandler;
copiedHandlerBlock.firstBasicBlockOfHandlerBlock = sourceHandlerBlock.firstBasicBlockOfHandlerBlock;
copiedHandlerBlock.lastBasicBlockOfHandlerBlock = sourceHandlerBlock.lastBasicBlockOfHandlerBlock;
copiedStartBasicBlock.handlerBlocks.Add(copiedHandlerBlock);
}
}
// copies recursively the next basic block of the method CFG (with a switch branch as entry branch)
private void copyMethodCfgRecursively(List<BasicBlock> processedBasicBlocks, BasicBlock sourceBasicBlock, ref BasicBlock targetBasicBlock, SwitchBranchTarget copiedEntryBranch, int takenEntryBranchIdx) {
// check if source basic block was already processed
if (processedBasicBlocks.Contains(sourceBasicBlock)) {
bool found = false;
foreach (BasicBlock searchBasicBlock in this.basicBlocks) {
if (searchBasicBlock.id == sourceBasicBlock.id) {
// set entry branch target
if (takenEntryBranchIdx == -1) {
copiedEntryBranch.notTakenTarget = searchBasicBlock;
}
else {
// fill switch taken branch list with empty elements when index is out of range
while (copiedEntryBranch.takenTarget.Count() <= takenEntryBranchIdx) {
copiedEntryBranch.takenTarget.Add(null);
}
copiedEntryBranch.takenTarget[takenEntryBranchIdx] = searchBasicBlock;
}
searchBasicBlock.entryBranches.Add(copiedEntryBranch);
found = true;
break;
}
}
if (!found) {
throw new ArgumentException("Copied basic block was not found.");
}
return;
}
// add source basic block to the list of already processed basic blocks
processedBasicBlocks.Add(sourceBasicBlock);
// create copy of the source basic block
targetBasicBlock = new BasicBlock();
this.basicBlocks.Add(targetBasicBlock);
// set entry branch target
if (takenEntryBranchIdx == -1) {
copiedEntryBranch.notTakenTarget = targetBasicBlock;
}
else {
// fill switch taken branch list with empty elements when index is out of range
while (copiedEntryBranch.takenTarget.Count() <= takenEntryBranchIdx) {
copiedEntryBranch.takenTarget.Add(null);
}
copiedEntryBranch.takenTarget[takenEntryBranchIdx] = targetBasicBlock;
}
targetBasicBlock.entryBranches.Add(copiedEntryBranch);
// copy simple values
targetBasicBlock.id = sourceBasicBlock.id;
targetBasicBlock.semanticId = sourceBasicBlock.semanticId;
targetBasicBlock.startIdx = sourceBasicBlock.startIdx;
targetBasicBlock.endIdx = sourceBasicBlock.endIdx;
// copy all operations of the basic block
foreach (IOperation operation in sourceBasicBlock.operations) {
InternalOperation copiedOperation = new InternalOperation();
copiedOperation.OperationCode = operation.OperationCode;
copiedOperation.Value = operation.Value;
copiedOperation.Offset = operation.Offset;
copiedOperation.Location = operation.Location;
targetBasicBlock.operations.Add(copiedOperation);
}
// process rest of the cfg and copy the exit branch
if ((sourceBasicBlock.exitBranch as NoBranchTarget) != null) {
NoBranchTarget exitBranch = (sourceBasicBlock.exitBranch as NoBranchTarget);
// create a copied exit branch
NoBranchTarget copiedExitBranch = new NoBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceBasicBlock.exitBranch as UnconditionalBranchTarget != null) {
UnconditionalBranchTarget exitBranch = (sourceBasicBlock.exitBranch as UnconditionalBranchTarget);
// create a copied exit branch
UnconditionalBranchTarget copiedExitBranch = new UnconditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceBasicBlock.exitBranch as ConditionalBranchTarget != null) {
ConditionalBranchTarget exitBranch = (sourceBasicBlock.exitBranch as ConditionalBranchTarget);
// create a copied exit branch
ConditionalBranchTarget copiedExitBranch = new ConditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch, true);
// process branch and next basic block
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.notTakenTarget, ref nextCopiedBasicBlock, copiedExitBranch, false);
}
else if (sourceBasicBlock.exitBranch as SwitchBranchTarget != null) {
SwitchBranchTarget exitBranch = (sourceBasicBlock.exitBranch as SwitchBranchTarget);
// create a copied exit branch
SwitchBranchTarget copiedExitBranch = new SwitchBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// first process not taken branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.notTakenTarget, ref nextCopiedBasicBlock, copiedExitBranch, -1);
// process all taken branches and next basic blocks
for (int idx = 0; idx < exitBranch.takenTarget.Count(); idx++) {
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget.ElementAt(idx), ref nextCopiedBasicBlock, copiedExitBranch, idx);
}
}
else if (sourceBasicBlock.exitBranch as ExitBranchTarget != null) {
// create a copied exit branch
ExitBranchTarget copiedExitBranch = new ExitBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
}
else if (sourceBasicBlock.exitBranch as ThrowBranchTarget != null) {
// create a copied exit branch
ThrowBranchTarget copiedExitBranch = new ThrowBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
}
else if (sourceBasicBlock.exitBranch as TryBlockTarget != null) {
TryBlockTarget exitBranch = (sourceBasicBlock.exitBranch as TryBlockTarget);
// create a copied exit branch
TryBlockTarget copiedExitBranch = new TryBlockTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.takenTarget, ref nextCopiedBasicBlock, copiedExitBranch);
}
else if (sourceBasicBlock.exitBranch as ExceptionBranchTarget != null) {
ExceptionBranchTarget exitBranch = (sourceBasicBlock.exitBranch as ExceptionBranchTarget);
// create a copied exit branch
ExceptionBranchTarget copiedExitBranch = new ExceptionBranchTarget();
copiedExitBranch.sourceBasicBlock = targetBasicBlock;
targetBasicBlock.exitBranch = copiedExitBranch;
// process branch and next basic block
BasicBlock nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.exceptionTarget, ref nextCopiedBasicBlock, copiedExitBranch, true);
// process branch and next basic block
nextCopiedBasicBlock = null;
this.copyMethodCfgRecursively(processedBasicBlocks, exitBranch.exitTarget, ref nextCopiedBasicBlock, copiedExitBranch, false);
}
else {
throw new ArgumentException("Do not know how to handle exit branch.");
}
// copy all try blocks
foreach (TryBlock sourceTryBlock in sourceBasicBlock.tryBlocks) {
TryBlock copiedTryBlock = new TryBlock();
copiedTryBlock.exceptionHandler = sourceTryBlock.exceptionHandler;
copiedTryBlock.firstBasicBlockOfTryBlock = sourceTryBlock.firstBasicBlockOfTryBlock;
copiedTryBlock.lastBasicBlockOfTryBlock = sourceTryBlock.lastBasicBlockOfTryBlock;
targetBasicBlock.tryBlocks.Add(copiedTryBlock);
}
// copy all handler blocks
foreach (HandlerBlock sourceHandlerBlock in sourceBasicBlock.handlerBlocks) {
HandlerBlock copiedHandlerBlock = new HandlerBlock();
copiedHandlerBlock.exceptionHandler = sourceHandlerBlock.exceptionHandler;
copiedHandlerBlock.typeOfHandler = sourceHandlerBlock.typeOfHandler;
copiedHandlerBlock.firstBasicBlockOfHandlerBlock = sourceHandlerBlock.firstBasicBlockOfHandlerBlock;
copiedHandlerBlock.lastBasicBlockOfHandlerBlock = sourceHandlerBlock.lastBasicBlockOfHandlerBlock;
targetBasicBlock.handlerBlocks.Add(copiedHandlerBlock);
}
}
void createNoBranch(BasicBlock deadCodeBasicBlock)
{
// Set the dead code block above some other block.
var exitBranch = new NoBranchTarget();
exitBranch.sourceBasicBlock = deadCodeBasicBlock;
deadCodeBasicBlock.exitBranch = exitBranch;
BasicBlock targetBlock = null;
do {
targetBlock = randomTargetBlock();
// Skip blocks that already have a "no branch" as entry.
foreach(var entryBranch in targetBlock.entryBranches) {
if(entryBranch is NoBranchTarget) {
targetBlock = null;
break;
}
}
} while(targetBlock == null);
targetBlock.entryBranches.Add(exitBranch);
exitBranch.takenTarget = targetBlock;
}
// this function creates all methods that are needed for the generated graph
public void createGraphMethods() {
this.logger.writeLine("Adding graph methods to \"" + this.targetClass.ToString() + "\"");
// check if the graph is already initialized (needed to create the methods)
if (this.graph == null) {
throw new ArgumentException("Graph is not initialized.");
}
// if debugging is activated
// => add field for the basic block trace file
if (this.debugging
|| this.trace) {
this.logger.writeLine("Debugging activated: Adding field for a basic block tracer file");
// add trace writer field
this.debuggingTraceWriter = new FieldDefinition();
this.debuggingTraceWriter.IsCompileTimeConstant = false;
this.debuggingTraceWriter.IsNotSerialized = false;
this.debuggingTraceWriter.IsReadOnly = false;
this.debuggingTraceWriter.IsRuntimeSpecial = false;
this.debuggingTraceWriter.IsSpecialName = false;
this.debuggingTraceWriter.Type = this.helperClass.systemIOStreamWriter;
this.debuggingTraceWriter.IsStatic = false;
this.debuggingTraceWriter.Name = host.NameTable.GetNameFor("DEBUG_traceWriter");
this.debuggingTraceWriter.Visibility = TypeMemberVisibility.Public;
this.debuggingTraceWriter.InternFactory = host.InternFactory;
this.debuggingTraceWriter.ContainingTypeDefinition = this.targetClass;
this.targetClass.Fields.Add(this.debuggingTraceWriter);
}
// create a method that can be called to generate the graph
this.buildGraphMethod = this.helperClass.createNewMethod("buildGraph", this.targetClass, host.PlatformType.SystemVoid, TypeMemberVisibility.Public, null, CallingConvention.HasThis, false, false, true); // TODO RENAME
ILGenerator ilGenerator = new ILGenerator(host, this.buildGraphMethod);
// check if graph was already build
// => if it was jump to exit
ILGeneratorLabel buildGraphExitLabel = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerGet);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brfalse, buildGraphExitLabel);
// set initial node (root of the tree)
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Ldarg_0); // needed as argument for the constructor
ilGenerator.Emit(OperationCode.Newobj, this.graph.startingNode.constructorToUse);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerSet);
// build rest of graph in a "pseudo recursive" manner
MethodDefinition newMethodToCall = this.addNodeRecursively(this.graph.startingNode, 1, "addNode_0"); // TODO: method name
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerGet);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Callvirt, newMethodToCall);
// exit
ilGenerator.MarkLabel(buildGraphExitLabel);
ilGenerator.Emit(OperationCode.Ret);
// create body
IMethodBody body = new ILGeneratorMethodBody(ilGenerator, true, 8, this.buildGraphMethod, Enumerable<ILocalDefinition>.Empty, Enumerable<ITypeDefinition>.Empty);
this.buildGraphMethod.Body = body;
// create exchangeNodes method
List<IParameterDefinition> parameters = new List<IParameterDefinition>();
// node type parameter
ParameterDefinition parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.nodeInterface;
parameters.Add(parameter);
// int array parameter for path to node one
VectorTypeReference intArrayType = new VectorTypeReference();
intArrayType.ElementType = this.host.PlatformType.SystemInt32;
intArrayType.Rank = 1;
intArrayType.IsFrozen = true;
intArrayType.IsValueType = false;
intArrayType.InternFactory = host.InternFactory;
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = intArrayType;
parameters.Add(parameter);
// int array parameter for path to node two
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = intArrayType;
parameters.Add(parameter);
this.exchangeNodesMethod = this.helperClass.createNewMethod("exchangeNodes", this.targetClass, host.PlatformType.SystemVoid, TypeMemberVisibility.Public, parameters, CallingConvention.HasThis, false, false, true); // TODO RENAME
ilGenerator = new ILGenerator(host, this.exchangeNodesMethod);
List<ILocalDefinition> localVariables = new List<ILocalDefinition>();
// create local integer variable needed for the loops
LocalDefinition loopIntLocal = new LocalDefinition();
loopIntLocal.IsReference = false;
loopIntLocal.IsPinned = false;
loopIntLocal.IsModified = false;
loopIntLocal.Type = this.host.PlatformType.SystemInt32;
loopIntLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(loopIntLocal);
// create local iNode variable needed for nodeOne
LocalDefinition nodeOneLocal = new LocalDefinition();
nodeOneLocal.IsReference = false;
nodeOneLocal.IsPinned = false;
nodeOneLocal.IsModified = false;
nodeOneLocal.Type = this.nodeInterface;
nodeOneLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(nodeOneLocal);
// create local iNode variable needed for prevNodeOne
LocalDefinition prevNodeOneLocal = new LocalDefinition();
prevNodeOneLocal.IsReference = false;
prevNodeOneLocal.IsPinned = false;
prevNodeOneLocal.IsModified = false;
prevNodeOneLocal.Type = this.nodeInterface;
prevNodeOneLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(prevNodeOneLocal);
// create local integer variable needed for prevNodeOneIdx
LocalDefinition prevNodeOneIdxLocal = new LocalDefinition();
prevNodeOneIdxLocal.IsReference = false;
prevNodeOneIdxLocal.IsPinned = false;
prevNodeOneIdxLocal.IsModified = false;
prevNodeOneIdxLocal.Type = this.host.PlatformType.SystemInt32;
prevNodeOneIdxLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(prevNodeOneIdxLocal);
// create local iNode variable needed for nodeTwo
LocalDefinition nodeTwoLocal = new LocalDefinition();
nodeTwoLocal.IsReference = false;
nodeTwoLocal.IsPinned = false;
nodeTwoLocal.IsModified = false;
nodeTwoLocal.Type = this.nodeInterface;
nodeTwoLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(nodeTwoLocal);
// create local iNode variable needed for prevNodeOne
LocalDefinition prevNodeTwoLocal = new LocalDefinition();
prevNodeTwoLocal.IsReference = false;
prevNodeTwoLocal.IsPinned = false;
prevNodeTwoLocal.IsModified = false;
prevNodeTwoLocal.Type = this.nodeInterface;
prevNodeTwoLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(prevNodeTwoLocal);
// create local integer variable needed for prevNodeOneIdx
LocalDefinition prevNodeTwoIdxLocal = new LocalDefinition();
prevNodeTwoIdxLocal.IsReference = false;
prevNodeTwoIdxLocal.IsPinned = false;
prevNodeTwoIdxLocal.IsModified = false;
prevNodeTwoIdxLocal.Type = this.host.PlatformType.SystemInt32;
prevNodeTwoIdxLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(prevNodeTwoIdxLocal);
// create local iNode variable needed for temp
LocalDefinition tempNodeLocal = new LocalDefinition();
tempNodeLocal.IsReference = false;
tempNodeLocal.IsPinned = false;
tempNodeLocal.IsModified = false;
tempNodeLocal.Type = this.nodeInterface;
tempNodeLocal.MethodDefinition = this.exchangeNodesMethod;
localVariables.Add(tempNodeLocal);
// initialize local variables
/*
iNode nodeOne = givenStartingNode;
iNode prevNodeOne = null;
int prevNodeOneIdx = 0;
*/
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Stloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Stloc, prevNodeOneLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, prevNodeOneIdxLocal);
// initialize loop
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
ILGeneratorLabel loopConditionAndIncBranch = new ILGeneratorLabel();
ILGeneratorLabel loopConditionBranch = new ILGeneratorLabel();
ILGeneratorLabel loopStartBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, loopConditionBranch);
// start of the code in the loop
/*
if (nodeOne.getNode(pathToNodeOne[i]) != null) {
*/
ilGenerator.MarkLabel(loopStartBranch);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldelem_I4);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, loopConditionAndIncBranch);
// get the node of the graph that should be exchanged (nodeOne)
/*
prevNodeOne = nodeOne;
prevNodeOneIdx = pathToNodeOne[i];
nodeOne = nodeOne.getNode(pathToNodeOne[i]);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Stloc, prevNodeOneLocal);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldelem_I4);
ilGenerator.Emit(OperationCode.Stloc, prevNodeOneIdxLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, prevNodeOneIdxLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Stloc, nodeOneLocal);
// increment counter of loop
ilGenerator.MarkLabel(loopConditionAndIncBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
// loop condition
/*
for (int i = 0; i < pathToNodeOne.Length; i++) {
*/
ilGenerator.MarkLabel(loopConditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldlen);
ilGenerator.Emit(OperationCode.Conv_I4);
ilGenerator.Emit(OperationCode.Clt);
ilGenerator.Emit(OperationCode.Brtrue, loopStartBranch);
// initialize local variables
/*
iNode nodeTwo = givenStartingNode;
iNode prevNodeTwo = null;
int prevNodeTwoIdx = 0;
*/
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Stloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Stloc, prevNodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, prevNodeTwoIdxLocal);
// initialize loop
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
loopConditionAndIncBranch = new ILGeneratorLabel();
loopConditionBranch = new ILGeneratorLabel();
loopStartBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, loopConditionBranch);
// start of the code in the loop
/*
if (nodeTwo.getNode(pathToNodeTwo[i]) != null) {
*/
ilGenerator.MarkLabel(loopStartBranch);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldelem_I4);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, loopConditionAndIncBranch);
// get the node of the graph that should be exchanged (nodeTwo)
/*
prevNodeTwo = nodeTwo;
prevNodeTwoIdx = pathToNodeTwo[i];
nodeTwo = nodeTwo.getNode(pathToNodeTwo[i]);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Stloc, prevNodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldelem_I4);
ilGenerator.Emit(OperationCode.Stloc, prevNodeTwoIdxLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, prevNodeTwoIdxLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Stloc, nodeTwoLocal);
// increment counter of loop
ilGenerator.MarkLabel(loopConditionAndIncBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
// loop condition
/*
for (int i = 0; i < pathToNodeTwo.Length; i++) {
*/
ilGenerator.MarkLabel(loopConditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ldlen);
ilGenerator.Emit(OperationCode.Conv_I4);
ilGenerator.Emit(OperationCode.Clt);
ilGenerator.Emit(OperationCode.Brtrue, loopStartBranch);
// initialize loop
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
loopConditionAndIncBranch = new ILGeneratorLabel();
loopConditionBranch = new ILGeneratorLabel();
loopStartBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, loopConditionBranch);
// start of the code in the loop
ilGenerator.MarkLabel(loopStartBranch);
/*
if (nodeOne.getNode(i) == nodeTwo) {
*/
ILGeneratorLabel conditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brfalse, conditionBranch);
/*
nodeOne.setNode(nodeTwo.getNode(i), i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
/*
nodeTwo.setNode(nodeOne, i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
ilGenerator.Emit(OperationCode.Br, loopConditionAndIncBranch);
/*
else if (nodeTwo.getNode(i) == nodeOne) {
*/
ilGenerator.MarkLabel(conditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ceq);
conditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brfalse, conditionBranch);
/*
nodeTwo.setNode(nodeOne.getNode(i), i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
/*
nodeOne.setNode(nodeTwo, i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
ilGenerator.Emit(OperationCode.Br, loopConditionAndIncBranch);
/*
else {
*/
ilGenerator.MarkLabel(conditionBranch);
/*
temp = nodeOne.getNode(i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Stloc, tempNodeLocal);
/*
nodeOne.setNode(nodeTwo.getNode(i), i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
/*
nodeTwo.setNode(temp, i);
*/
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, tempNodeLocal);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
// increment counter of loop
ilGenerator.MarkLabel(loopConditionAndIncBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
ilGenerator.Emit(OperationCode.Stloc, loopIntLocal);
// loop condition
/*
for (int i = 0; i < GRAPH_DIMENSION; i++) {
*/
ilGenerator.MarkLabel(loopConditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, loopIntLocal);
ilGenerator.Emit(OperationCode.Ldc_I4, this.graphDimension);
ilGenerator.Emit(OperationCode.Clt);
ilGenerator.Emit(OperationCode.Brtrue, loopStartBranch);
/*
if (prevNodeOne != null) {
*/
conditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldloc, prevNodeOneLocal);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, conditionBranch);
/*
if (prevNodeOne != nodeTwo) {
*/
ILGeneratorLabel exitConditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldloc, prevNodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, exitConditionBranch);
/*
prevNodeOne.setNode(nodeTwo, prevNodeOneIdx);
*/
ilGenerator.Emit(OperationCode.Ldloc, prevNodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, prevNodeOneIdxLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
ilGenerator.Emit(OperationCode.Br, exitConditionBranch);
/*
else {
*/
ilGenerator.MarkLabel(conditionBranch);
/*
this.graphStartNode = nodeTwo;
*/
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Ldloc, nodeTwoLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerSet);
ilGenerator.MarkLabel(exitConditionBranch);
/*
if (prevNodeTwo != null) {
*/
conditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldloc, prevNodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldnull);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, conditionBranch);
/*
if (prevNodeTwo != nodeOne) {
*/
exitConditionBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Ldloc, prevNodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Brtrue, exitConditionBranch);
/*
prevNodeTwo.setNode(nodeOne, prevNodeTwoIdx);
*/
ilGenerator.Emit(OperationCode.Ldloc, prevNodeTwoLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Ldloc, prevNodeTwoIdxLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
ilGenerator.Emit(OperationCode.Br, exitConditionBranch);
/*
else {
*/
ilGenerator.MarkLabel(conditionBranch);
/*
this.graphStartNode = nodeOne;
*/
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Ldloc, nodeOneLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerSet);
ilGenerator.MarkLabel(exitConditionBranch);
ilGenerator.Emit(OperationCode.Ret);
// create body
body = new ILGeneratorMethodBody(ilGenerator, true, 8, this.exchangeNodesMethod, localVariables, Enumerable<ITypeDefinition>.Empty);
this.exchangeNodesMethod.Body = body;
// check if debugging is activated
// => add function to dump graph as .dot file
if (this.debugging) {
this.logger.writeLine("Debugging activated: Adding code to dump graph as .dot file");
// create dumpGraph method
parameters = new List<IParameterDefinition>();
// string parameter
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.host.PlatformType.SystemString;
parameter.Index = 0;
parameters.Add(parameter);
// node type parameter (current pointer of debug method)
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.nodeInterface;
parameter.Index = 1;
parameters.Add(parameter);
// node type parameter (current pointer of caller)
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.nodeInterface;
parameter.Index = 2;
parameters.Add(parameter);
this.debuggingDumpGraphMethod = this.helperClass.createNewMethod("DEBUG_dumpGraph", this.targetClass, host.PlatformType.SystemVoid, TypeMemberVisibility.Public, parameters, CallingConvention.HasThis, false, false, true);
// create dumpGraphRec method
parameters = new List<IParameterDefinition>();
// stream writer parameter
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.helperClass.systemIOStreamWriter;
parameter.Index = 0;
parameters.Add(parameter);
// string parameter
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.host.PlatformType.SystemString;
parameter.Index = 1;
parameters.Add(parameter);
// node type parameter (current pointer of debug method)
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.nodeInterface;
parameter.Index = 2;
parameters.Add(parameter);
// node type parameter (current pointer of caller)
ParameterDefinition currentNodeCallerParameter = new ParameterDefinition();
currentNodeCallerParameter.IsIn = false;
currentNodeCallerParameter.IsOptional = false;
currentNodeCallerParameter.IsOut = false;
currentNodeCallerParameter.Type = this.nodeInterface;
currentNodeCallerParameter.Index = 3;
parameters.Add(currentNodeCallerParameter);
MethodDefinition dumpGraphRecMethod = this.helperClass.createNewMethod("DEBUG_dumpGraphRec", this.targetClass, host.PlatformType.SystemVoid, TypeMemberVisibility.Public, parameters, CallingConvention.HasThis, false, false, true);
currentNodeCallerParameter.ContainingSignature = dumpGraphRecMethod; // is needed when parameter is accessed via Ldarg
// create body for dumpGraph method
ilGenerator = new ILGenerator(host, this.debuggingDumpGraphMethod);
localVariables = new List<ILocalDefinition>();
// create local string variable needed for debugging code
LocalDefinition nodeNameLocal = new LocalDefinition();
nodeNameLocal.IsReference = false;
nodeNameLocal.IsPinned = false;
nodeNameLocal.IsModified = false;
nodeNameLocal.Type = this.host.PlatformType.SystemString;
nodeNameLocal.MethodDefinition = this.debuggingDumpGraphMethod;
localVariables.Add(nodeNameLocal);
// create local stream writer variable needed for debugging code
LocalDefinition streamWriterLocal = new LocalDefinition();
streamWriterLocal.IsReference = false;
streamWriterLocal.IsPinned = false;
streamWriterLocal.IsModified = false;
streamWriterLocal.Type = this.helperClass.systemIOStreamWriter;
streamWriterLocal.MethodDefinition = this.debuggingDumpGraphMethod;
localVariables.Add(streamWriterLocal);
// create local integer variable for the for loop needed for debugging code
LocalDefinition forIntegerLocal = new LocalDefinition();
forIntegerLocal.IsReference = false;
forIntegerLocal.IsPinned = false;
forIntegerLocal.IsModified = false;
forIntegerLocal.Type = this.host.PlatformType.SystemInt32;
forIntegerLocal.MethodDefinition = this.debuggingDumpGraphMethod;
localVariables.Add(forIntegerLocal);
// generate dump file location string
ilGenerator.Emit(OperationCode.Ldstr, this.debuggingDumpLocation + this.debuggingDumpFilePrefix);
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldstr, ".dot");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// initialize io stream writer
ilGenerator.Emit(OperationCode.Newobj, this.helperClass.streamWriterCtor);
ilGenerator.Emit(OperationCode.Stloc, streamWriterLocal);
// initialize .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldstr, "digraph G {");
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// check if the node to dump is the same as the current node of the class
// if it is => color the current dumped node
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ceq);
ILGeneratorLabel currentNodeEqualDumpedNodeBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brtrue, currentNodeEqualDumpedNodeBranch);
// case: current dumped node is not the current node of the class
// create name for the nodes
ilGenerator.Emit(OperationCode.Ldstr, "node_0");
ilGenerator.Emit(OperationCode.Stloc, nodeNameLocal);
// write current node to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, " [shape=record]");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// jump to the end of this case
ILGeneratorLabel currentNodeDumpedBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, currentNodeDumpedBranch);
// case: current dumped node is the current node of the class
ilGenerator.MarkLabel(currentNodeEqualDumpedNodeBranch);
// create name for the nodes
ilGenerator.Emit(OperationCode.Ldstr, "node_0");
ilGenerator.Emit(OperationCode.Stloc, nodeNameLocal);
// write current node to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, " [shape=record, color=blue]");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// end of the case
ilGenerator.MarkLabel(currentNodeDumpedBranch);
// write start of label of the current node to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, " [label=\"{");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write current node name to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldstr, "Node: ");
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, "|");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write current node id to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldstr, "Id: ");
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Callvirt, this.debuggingInterfaceIdGet);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write end of label of the current node to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldstr, "}\"]");
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// initialize counter of for loop
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, forIntegerLocal);
// jump to loop condition
loopConditionBranch = new ILGeneratorLabel();
loopStartBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, loopConditionBranch);
// start of loop
ilGenerator.MarkLabel(loopStartBranch);
// check if childNodes[i] == startNode
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerGet);
ilGenerator.Emit(OperationCode.Ceq);
loopConditionAndIncBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brtrue, loopConditionAndIncBranch);
// write connection of current node to next node to .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
// generate first part of the string
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, " -> ");
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// generate second part of string and concat to first part
ilGenerator.Emit(OperationCode.Ldstr, "_");
ilGenerator.Emit(OperationCode.Ldloca, forIntegerLocal);
ilGenerator.Emit(OperationCode.Call, this.helperClass.int32ToString);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// write to .dot file
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// call method that dumps graph recursively ( this.dumpGraphRec(streamWriter, String name, nextNode) )
ilGenerator.Emit(OperationCode.Ldarg_0);
// push stream writer parameter
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
// push string parameter
ilGenerator.Emit(OperationCode.Ldloc, nodeNameLocal);
ilGenerator.Emit(OperationCode.Ldstr, "_");
ilGenerator.Emit(OperationCode.Ldloca, forIntegerLocal);
ilGenerator.Emit(OperationCode.Call, this.helperClass.int32ToString);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// push node parameter (current pointer of debug method)
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
// push node parameter (current pointer of the caller)
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Callvirt, dumpGraphRecMethod);
// increment loop counter
ilGenerator.MarkLabel(loopConditionAndIncBranch);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
ilGenerator.Emit(OperationCode.Stloc, forIntegerLocal);
// loop condition
ilGenerator.MarkLabel(loopConditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Ldc_I4, this.graphDimension);
ilGenerator.Emit(OperationCode.Clt);
ilGenerator.Emit(OperationCode.Brtrue, loopStartBranch);
// end .dot file
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Ldstr, "}");
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// close io stream writer
ilGenerator.Emit(OperationCode.Ldloc, streamWriterLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterClose);
ilGenerator.Emit(OperationCode.Ret);
// create body
body = new ILGeneratorMethodBody(ilGenerator, true, 8, this.debuggingDumpGraphMethod, localVariables, Enumerable<ITypeDefinition>.Empty);
this.debuggingDumpGraphMethod.Body = body;
// create body for dumpGraphRec method
localVariables = new List<ILocalDefinition>();
ilGenerator = new ILGenerator(host, dumpGraphRecMethod);
// create local integer variable for the for loop needed for debugging code
forIntegerLocal = new LocalDefinition();
forIntegerLocal.IsReference = false;
forIntegerLocal.IsPinned = false;
forIntegerLocal.IsModified = false;
forIntegerLocal.Type = this.host.PlatformType.SystemInt32;
forIntegerLocal.MethodDefinition = dumpGraphRecMethod;
localVariables.Add(forIntegerLocal);
// check if the node to dump is the same as the current node of the class
// if it is => color the current dumped node
ilGenerator.Emit(OperationCode.Ldarg, currentNodeCallerParameter);
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ceq);
currentNodeEqualDumpedNodeBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brtrue, currentNodeEqualDumpedNodeBranch);
// case: current dumped node is not the current node of the class
// write current node to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, " [shape=record]");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// jump to the end of this case
currentNodeDumpedBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, currentNodeDumpedBranch);
// case: current dumped node is the current node of the class
ilGenerator.MarkLabel(currentNodeEqualDumpedNodeBranch);
// write current node to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, " [shape=record, color=blue]");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// end of the case
ilGenerator.MarkLabel(currentNodeDumpedBranch);
// write start of label of the current node to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, " [label=\"{");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write current node name to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldstr, "Node: ");
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, "|");
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write current node id to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldstr, "Id: ");
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Callvirt, this.debuggingInterfaceIdGet);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatTwo);
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWrite);
// write end of label of the current node to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldstr, "}\"]");
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// initialize counter of for loop
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Stloc, forIntegerLocal);
// jump to loop condition
loopConditionBranch = new ILGeneratorLabel();
loopStartBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Br, loopConditionBranch);
// start of loop
ilGenerator.MarkLabel(loopStartBranch);
// check if childNodes[i] == startNode
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerGet);
ilGenerator.Emit(OperationCode.Ceq);
loopConditionAndIncBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brtrue, loopConditionAndIncBranch);
// write connection of current node to next node to .dot file
ilGenerator.Emit(OperationCode.Ldarg_1);
// generate first part of the string
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, " -> ");
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// generate second part of string and concat to first part
ilGenerator.Emit(OperationCode.Ldstr, "_");
ilGenerator.Emit(OperationCode.Ldloca, forIntegerLocal);
ilGenerator.Emit(OperationCode.Call, this.helperClass.int32ToString);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// write to .dot file
ilGenerator.Emit(OperationCode.Callvirt, this.helperClass.textWriterWriteLine);
// call method that dumps graph recursively ( this.dumpGraphRec(streamWriter, String name, nextNode) )
ilGenerator.Emit(OperationCode.Ldarg_0);
// push stream writer parameter
ilGenerator.Emit(OperationCode.Ldarg_1);
// push string parameter
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldstr, "_");
ilGenerator.Emit(OperationCode.Ldloca, forIntegerLocal);
ilGenerator.Emit(OperationCode.Call, this.helperClass.int32ToString);
ilGenerator.Emit(OperationCode.Call, this.helperClass.stringConcatThree);
// push node parameter (current pointer of debug method)
ilGenerator.Emit(OperationCode.Ldarg_3);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
// push node parameter (current pointer of the caller)
ilGenerator.Emit(OperationCode.Ldarg, currentNodeCallerParameter);
ilGenerator.Emit(OperationCode.Callvirt, dumpGraphRecMethod);
// increment loop counter
ilGenerator.MarkLabel(loopConditionAndIncBranch);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
ilGenerator.Emit(OperationCode.Stloc, forIntegerLocal);
// loop condition
ilGenerator.MarkLabel(loopConditionBranch);
ilGenerator.Emit(OperationCode.Ldloc, forIntegerLocal);
ilGenerator.Emit(OperationCode.Ldc_I4, this.graphDimension);
ilGenerator.Emit(OperationCode.Clt);
ilGenerator.Emit(OperationCode.Brtrue, loopStartBranch);
ilGenerator.Emit(OperationCode.Ret);
// create body
body = new ILGeneratorMethodBody(ilGenerator, true, 8, dumpGraphRecMethod, localVariables, Enumerable<ITypeDefinition>.Empty);
dumpGraphRecMethod.Body = body;
}
// inject code to build the graph to all constructors (except the artificial added ctor for a graph node)
foreach (MethodDefinition ctorMethod in this.targetClass.Methods) {
// only process constructors
if (!ctorMethod.IsConstructor) {
continue;
}
// skip the artificial added ctor with the node interface as parameter
bool skip = false;
if (ctorMethod.Parameters != null) {
foreach (IParameterDefinition ctorParameter in ctorMethod.Parameters) {
if (ctorParameter.Type == this.nodeInterface) {
skip = true;
break;
}
}
}
if (skip) {
continue;
}
this.logger.writeLine("Injecting code to build graph to \"" + this.logger.makeFuncSigString(ctorMethod) + "\"");
MethodCfg ctorMethodCfg = this.cfgBuilder.buildCfgForMethod(ctorMethod);
// create new basic block that builds the graph
// (will be the new starting basic block of the method)
BasicBlock startBasicBlock = new BasicBlock();
startBasicBlock.startIdx = 0;
startBasicBlock.endIdx = 0;
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.buildGraphMethod));
if (this.debugging) {
// dump generated graph
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(ctorMethodCfg.method)));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
}
// create exit branch for the new start basic block
NoBranchTarget startExitBranch = new NoBranchTarget();
startExitBranch.sourceBasicBlock = startBasicBlock;
startBasicBlock.exitBranch = startExitBranch;
// set the original start basic block as the target of the exit branch
startExitBranch.takenTarget = ctorMethodCfg.startBasicBlock;
ctorMethodCfg.startBasicBlock.entryBranches.Add(startExitBranch);
// set new start basic block as start basic block of the method cfg
ctorMethodCfg.startBasicBlock = startBasicBlock;
ctorMethodCfg.basicBlocks.Add(startBasicBlock);
this.cfgBuilder.createMethodFromCfg(ctorMethodCfg);
}
}
private void removeReplaceUnconditionalBranchesIter(CfgManipulator cfgManipulator, GraphRandomStateGenerator randomStateGenerator, MethodCfg originalMethodCfg, MethodCfg methodCfg, BasicBlock startBasicBlock, LocalDefinition intStateLocal, LocalDefinition currentNodeLocal) {
// create a list of basic blocks that still have to be processed by the algorithm
List<BasicBlock> basicBlocksToProcess = new List<BasicBlock>(methodCfg.basicBlocks);
System.Console.WriteLine("Basic Blocks to process (Replace Unconditional Branches): " + basicBlocksToProcess.Count());
while (true) {
List<BasicBlock> copiedList = new List<BasicBlock>(basicBlocksToProcess);
foreach (BasicBlock currentBasicBlock in copiedList) {
// check if basic block has entry branches that can be optimized
bool hasUnconditionalBranchTarget = false;
bool hasNoBranchTarget = false;
foreach (IBranchTarget entryBranch in currentBasicBlock.entryBranches) {
if ((entryBranch as NoBranchTarget) != null) {
hasNoBranchTarget = true;
continue;
}
else if ((entryBranch as UnconditionalBranchTarget) != null) {
hasUnconditionalBranchTarget = true;
continue;
}
}
// skip if basic block already has no branch target
if (hasNoBranchTarget) {
// remove currently processed basic block from the list of basic blocks to process
basicBlocksToProcess.Remove(currentBasicBlock);
continue;
}
// skip if basic block does not have an unconditional branch target
if (!hasUnconditionalBranchTarget) {
// remove currently processed basic block from the list of basic blocks to process
basicBlocksToProcess.Remove(currentBasicBlock);
continue;
}
// replace one unconditional branch by a no branch
List<IBranchTarget> copiedBranchList = new List<IBranchTarget>(currentBasicBlock.entryBranches);
foreach (IBranchTarget entryBranch in copiedBranchList) {
if ((entryBranch as UnconditionalBranchTarget) != null) {
BasicBlock sourceBasicBlock = entryBranch.sourceBasicBlock;
// create replacement branch
NoBranchTarget replacementBranch = new NoBranchTarget();
replacementBranch.sourceBasicBlock = sourceBasicBlock;
replacementBranch.takenTarget = currentBasicBlock;
// replace old branch with new one
sourceBasicBlock.exitBranch = replacementBranch;
currentBasicBlock.entryBranches.Remove(entryBranch);
currentBasicBlock.entryBranches.Add(replacementBranch);
// replace unconditional branch instruction with nop
IOperation lastOperation = sourceBasicBlock.operations.ElementAt(sourceBasicBlock.operations.Count() - 1);
if (!CfgBuilder.isUnconditionalBranchOperation(lastOperation)) {
throw new ArgumentException("Last instruction of basic block have to be an unconditional branch.");
}
IOperation replacementOperation = this.helperClass.createNewOperation(OperationCode.Nop);
sourceBasicBlock.operations[sourceBasicBlock.operations.Count() - 1] = replacementOperation;
break;
}
}
// remove currently processed basic block from the list of basic blocks to process
basicBlocksToProcess.Remove(currentBasicBlock);
}
System.Console.WriteLine("Basic Blocks to process (Replace Unconditional Branches): " + basicBlocksToProcess.Count());
// check if basic blocks exist to process => if not break loop
if (basicBlocksToProcess.Count() == 0) {
break;
}
}
}
public void addObfuscationToMethod(MethodCfg methodCfg) {
MethodCfg copyMethodCfg = new MethodCfg(methodCfg);
CfgManipulator cfgManipulator = new CfgManipulator(this.module, this.host, this.logger, methodCfg);
GraphRandomStateGenerator randomStateGenerator = new GraphRandomStateGenerator(this.module, this.host, this.logger, cfgManipulator, this.helperClass, this.graph, methodCfg, this.debugging);
// DEBUG
if (this.debugging) {
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
// add local state variable
LocalDefinition intStateLocal = new LocalDefinition();
intStateLocal.IsReference = false;
intStateLocal.IsPinned = false;
intStateLocal.IsModified = false;
intStateLocal.Type = this.host.PlatformType.SystemInt32;
intStateLocal.MethodDefinition = methodCfg.method;
cfgManipulator.addLocalVariable(intStateLocal);
// add local current graph node variable
LocalDefinition currentNodeLocal = new LocalDefinition();
currentNodeLocal.IsReference = false;
currentNodeLocal.IsPinned = false;
currentNodeLocal.IsModified = false;
currentNodeLocal.Type = this.nodeInterface;
currentNodeLocal.MethodDefinition = methodCfg.method;
cfgManipulator.addLocalVariable(currentNodeLocal);
// create new basic block that sets the current node to the start node and get the state
// (will be the new starting basic block of the method)
BasicBlock startBasicBlock = new BasicBlock();
startBasicBlock.startIdx = 0;
startBasicBlock.endIdx = 0;
// set the current node pointer to the start node
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
startBasicBlock.operations.Add(this.helperClass.createNewOperation(OperationCode.Stloc, currentNodeLocal));
// initialize the random state generator
List<IOperation> tempOperations = randomStateGenerator.generateCodeInitializeRandomState();
startBasicBlock.operations.AddRange(tempOperations);
// set global state
tempOperations = randomStateGenerator.generateCodeSetRandomState(intStateLocal);
startBasicBlock.operations.AddRange(tempOperations);
// create exit branch for the new start basic block
NoBranchTarget startExitBranch = new NoBranchTarget();
startExitBranch.sourceBasicBlock = startBasicBlock;
startBasicBlock.exitBranch = startExitBranch;
// set the original start basic block as the target of the exit branch
startExitBranch.takenTarget = methodCfg.startBasicBlock;
methodCfg.startBasicBlock.entryBranches.Add(startExitBranch);
// set new start basic block as start basic block of the method cfg
methodCfg.startBasicBlock = startBasicBlock;
methodCfg.basicBlocks.Add(startBasicBlock);
// obfuscate the control flow
this.addMetadataIter(cfgManipulator, randomStateGenerator, copyMethodCfg, methodCfg, startBasicBlock, intStateLocal, currentNodeLocal);
this.processExitBranchesIter(cfgManipulator, randomStateGenerator, copyMethodCfg, methodCfg, startBasicBlock, intStateLocal, currentNodeLocal);
this.addOpaquePredicatesIter(cfgManipulator, randomStateGenerator, copyMethodCfg, methodCfg, startBasicBlock, intStateLocal, currentNodeLocal);
this.removeReplaceUnconditionalBranchesIter(cfgManipulator, randomStateGenerator, copyMethodCfg, methodCfg, startBasicBlock, intStateLocal, currentNodeLocal);
// fill dead code basic blocks with actual dead code
this.fillDeadCodeBasicBlocks(methodCfg);
this.obfuscateSemanticallyEquivalentBlocks(methodCfg);
// TODO QUICK FIX
// mutateBlocks() does not work when debugging is deactivated
// but since we only focus on probabilistic control flow, ignore it for now
this.debugging = true;
this.mutateBlocks(methodCfg);
this.debugging = false;
// if debugging is activated => add code that allows to trace the control flow through the method
if (this.debugging
|| this.trace) {
List<IOperation> traceWriterOperations = null;
// add code to the beginning of each basic block that writes to the trace file
for (int idx = 0; idx < methodCfg.basicBlocks.Count(); idx++) {
traceWriterOperations = new List<IOperation>();
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldfld, this.debuggingTraceWriter));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, "BB" + idx.ToString() + ";ID" + methodCfg.basicBlocks.ElementAt(idx).id.ToString()));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.helperClass.textWriterWriteLine));
methodCfg.basicBlocks.ElementAt(idx).operations.InsertRange(0, traceWriterOperations);
// check if the basic block has an exit branch
// => add code that closes the file handler of the trace file before the ret instruction
if ((methodCfg.basicBlocks.ElementAt(idx).exitBranch as ExitBranchTarget) != null) {
traceWriterOperations = new List<IOperation>();
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldfld, this.debuggingTraceWriter));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.helperClass.textWriterClose));
methodCfg.basicBlocks.ElementAt(idx).operations.InsertRange(methodCfg.basicBlocks.ElementAt(idx).operations.Count() - 1, traceWriterOperations);
}
}
// create local integer variable needed for the trace file code
LocalDefinition intLocal = new LocalDefinition();
intLocal.IsReference = false;
intLocal.IsPinned = false;
intLocal.IsModified = false;
intLocal.Type = this.host.PlatformType.SystemInt32;
intLocal.MethodDefinition = methodCfg.method;
cfgManipulator.addLocalVariable(intLocal);
traceWriterOperations = new List<IOperation>();
// get the hash code of this instance as unique object id
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.helperClass.objectGetHashCode));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Stloc, intLocal));
// initialize io stream writer for trace file (use object hash as id for this trace and only append)
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingDumpLocation + "\\" + this.debuggingTraceFilePrefix + "_"));
// cast random integer to string and store in object id
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloca, intLocal));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Call, this.helperClass.int32ToString));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, ".txt"));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Call, this.helperClass.stringConcatThree));
// only append to file
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldc_I4_1));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Newobj, this.helperClass.streamWriterCtorAppend));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Stfld, this.debuggingTraceWriter));
// write marker to trace file that marks the beginning of this trace
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldfld, this.debuggingTraceWriter));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, "\n------NEWSTART------\n"));
traceWriterOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.helperClass.textWriterWriteLine));
// add code to the beginning of the start basic block
methodCfg.startBasicBlock.operations.InsertRange(0, traceWriterOperations);
}
logger.dumpMethodCfg(copyMethodCfg, "copy_final");
return;
}
// creates a duplicate of the given source basic block with the branch targets to semantically equivalent basic blocks
// (not necessary the target basic block of the given source basic block)
private BasicBlock duplicateBasicBlock(MethodCfg originalMethodCfg, MethodCfg methodCfg, BasicBlock sourceBasicBlock) {
// search for a semantically equal basic block in the unmodified method CFG
int searchSementicId = sourceBasicBlock.semanticId;
BasicBlock copiedOriginalTargetBasicBlock = null;
if (searchSementicId == -1) {
throw new ArgumentException("No distinct semantic id given to search for.");
}
foreach (BasicBlock searchBasicBlock in originalMethodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
copiedOriginalTargetBasicBlock = searchBasicBlock;
break;
}
}
if (copiedOriginalTargetBasicBlock == null) {
throw new ArgumentException("Not able to find semantically equal basic block in copied CFG.");
}
// create a new basic block
BasicBlock newBasicBlock = new BasicBlock();
// copy simple values
newBasicBlock.semanticId = copiedOriginalTargetBasicBlock.semanticId;
newBasicBlock.startIdx = copiedOriginalTargetBasicBlock.startIdx;
newBasicBlock.endIdx = copiedOriginalTargetBasicBlock.endIdx;
// copy all operations of the basic block
foreach (IOperation operation in copiedOriginalTargetBasicBlock.operations) {
newBasicBlock.operations.Add(this.helperClass.createNewOperation(operation.OperationCode, operation.Value, operation.Location, operation.Offset));
}
if (copiedOriginalTargetBasicBlock.tryBlocks.Count() != 0
|| copiedOriginalTargetBasicBlock.handlerBlocks.Count() != 0) {
throw new ArgumentException("Not implemented yet.");
}
// create an exit branch for the new basic block
if ((copiedOriginalTargetBasicBlock.exitBranch as NoBranchTarget) != null) {
//throw new ArgumentException("Not implemented yet."); // TODO: problem here with having 2 no branches before a basic block (but not necessarily because all branches are processed and exchanged)
NoBranchTarget exitBranch = (copiedOriginalTargetBasicBlock.exitBranch as NoBranchTarget);
// create a copied exit branch
NoBranchTarget copiedExitBranch = new NoBranchTarget();
copiedExitBranch.sourceBasicBlock = newBasicBlock;
newBasicBlock.exitBranch = copiedExitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
searchSementicId = exitBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock targetBasicBlock = possibleTargetBasicBlocks.ElementAt(randPosition);
// set basic block as target for the branch
targetBasicBlock.entryBranches.Add(copiedExitBranch);
copiedExitBranch.takenTarget = targetBasicBlock;
}
else if (copiedOriginalTargetBasicBlock.exitBranch as UnconditionalBranchTarget != null) {
UnconditionalBranchTarget exitBranch = (copiedOriginalTargetBasicBlock.exitBranch as UnconditionalBranchTarget);
// create a copied exit branch
UnconditionalBranchTarget copiedExitBranch = new UnconditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = newBasicBlock;
newBasicBlock.exitBranch = copiedExitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
searchSementicId = exitBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock targetBasicBlock = possibleTargetBasicBlocks.ElementAt(randPosition);
// set basic block as target for the branch
targetBasicBlock.entryBranches.Add(copiedExitBranch);
copiedExitBranch.takenTarget = targetBasicBlock;
}
else if (copiedOriginalTargetBasicBlock.exitBranch as ConditionalBranchTarget != null) {
ConditionalBranchTarget exitBranch = (copiedOriginalTargetBasicBlock.exitBranch as ConditionalBranchTarget);
// create a copied exit branch
ConditionalBranchTarget copiedExitBranch = new ConditionalBranchTarget();
copiedExitBranch.sourceBasicBlock = newBasicBlock;
newBasicBlock.exitBranch = copiedExitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets) (for "taken" branch)
searchSementicId = exitBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock targetBasicBlock = possibleTargetBasicBlocks.ElementAt(randPosition);
// set basic block as target for the branch
targetBasicBlock.entryBranches.Add(copiedExitBranch);
copiedExitBranch.takenTarget = targetBasicBlock;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets) (for "not taken" branch)
searchSementicId = exitBranch.notTakenTarget.semanticId;
possibleTargetBasicBlocks = new List<BasicBlock>();
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
// use a random possible basic block as target
randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
targetBasicBlock = possibleTargetBasicBlocks.ElementAt(randPosition);
// set basic block as target for the branch
targetBasicBlock.entryBranches.Add(copiedExitBranch);
copiedExitBranch.notTakenTarget = targetBasicBlock;
}
else if (copiedOriginalTargetBasicBlock.exitBranch as SwitchBranchTarget != null) {
throw new ArgumentException("Not implemented yet.");
}
else if (copiedOriginalTargetBasicBlock.exitBranch as ExitBranchTarget != null) {
// create a copied exit branch
ExitBranchTarget copiedExitBranch = new ExitBranchTarget();
copiedExitBranch.sourceBasicBlock = newBasicBlock;
newBasicBlock.exitBranch = copiedExitBranch;
}
else if (copiedOriginalTargetBasicBlock.exitBranch as ThrowBranchTarget != null) {
throw new ArgumentException("Not implemented yet.");
}
else if (copiedOriginalTargetBasicBlock.exitBranch as TryBlockTarget != null) {
throw new ArgumentException("Not implemented yet.");
}
else if (copiedOriginalTargetBasicBlock.exitBranch as ExceptionBranchTarget != null) {
throw new ArgumentException("Not implemented yet.");
}
else {
throw new ArgumentException("Do not know how to handle exit branch.");
}
return newBasicBlock;
}