public virtual void Write(ILSwitch f)
{
InsertLineInfo(f);
Write("switch(");
Write(f.Condition);
WriteLine(") {");
Indent++;
foreach (var c in f.Cases)
{
if (c.Values == null)
{
WriteLine("default:");
}
else
{
foreach (var v in c.Values)
{
Write("case ");
Write(v);
WriteLine(":");
}
}
Write((ILBlock)c); // write it as a block
}
if (f.Default != null && f.Default.Body.Count > 0)
{
Write("default:");
Write(f.Default);
}
Indent--;
Write("}");
}
protected virtual ILSwitch VisitSwitch(ILSwitch switchStatement)
{
foreach (var child in switchStatement.GetChildren())
{
Visit(child);
}
return(switchStatement);
}
private void CompileSwitch(ILSwitch node)
{
CompileExpression(node.Condition, ExpectType.Primitive); //TODO: Switch on long
JavaBytecodeWriter.LookupswitchOperand operand = new JavaBytecodeWriter.LookupswitchOperand();
JavaInstruction switchInstr = new JavaInstruction(Java.OpCodes.lookupswitch, null, node);
codeGenerator.AddInstruction(switchInstr);
string labelsSufix = rnd.Next().ToString();
string defaultLabel = "default" + labelsSufix;
string exitLabel = "exit" + labelsSufix;
bool wasDefault = false;
List <Tuple <int, string> > pairs = new List <Tuple <int, string> >();
loopOrSwitchExitLabel.Push(exitLabel);
int index = 0;
foreach (ILSwitch.CaseBlock caseBlock in node.CaseBlocks)
{
if (caseBlock.Values == null)
{
codeGenerator.Label(defaultLabel);
wasDefault = true;
}
else
{
string thisCaseLabel = "case" + (index++) + labelsSufix;
foreach (int val in caseBlock.Values)
{
pairs.Add(new Tuple <int, string>(val, thisCaseLabel));
}
codeGenerator.Label(thisCaseLabel);
}
CompileBlock(caseBlock);
}
loopOrSwitchExitLabel.Pop();
if (!wasDefault)
{
codeGenerator.Label(defaultLabel);
}
codeGenerator.Label(exitLabel);
pairs.Sort((T1, T2) => (T1.Item1 <T2.Item1 ? -1 : T1.Item1> T2.Item1 ? 1 : 0));
operand.DefaultLabel = defaultLabel;
operand.Pairs = pairs.ToArray();
switchInstr.Operand = operand;
}
public JSSwitchCase TranslateNode(ILSwitch.CaseBlock block, TypeReference conditionType = null)
{
JSExpression[] values = null;
if (block.Values != null) {
if ((conditionType != null) && (conditionType.MetadataType == MetadataType.Char)) {
values = (from v in block.Values select JSLiteral.New(Convert.ToChar(v))).ToArray();
} else {
values = (from v in block.Values select JSLiteral.New(v)).ToArray();
}
}
return new JSSwitchCase(
values,
TranslateNode(new ILBlock(block.Body))
);
}
List<ILNode> FindConditions(HashSet<ControlFlowNode> scope, ControlFlowNode entryNode)
{
List<ILNode> result = new List<ILNode>();
HashSet<ControlFlowNode> agenda = new HashSet<ControlFlowNode>();
agenda.Add(entryNode);
while(agenda.Any()) {
ControlFlowNode node = agenda.First();
// Attempt for a good order
while(agenda.Contains(node.ImmediateDominator)) {
node = node.ImmediateDominator;
}
agenda.Remove(node);
// Find a block that represents a simple condition
if (scope.Contains(node)) {
ILBasicBlock block = node.UserData as ILBasicBlock;
if (block != null && block.Body.Count == 1) {
ILExpression condBranch = block.Body[0] as ILExpression;
// Switch
if (condBranch != null && condBranch.Operand is ILLabel[] && condBranch.Arguments.Count > 0) {
ILSwitch ilSwitch = new ILSwitch() {
Condition = condBranch,
DefaultGoto = block.FallthoughGoto
};
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue((ILLabel)block.FallthoughGoto.Operand, out fallTarget);
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (fallTarget != null)
frontiers.UnionWith(fallTarget.DominanceFrontier);
foreach(ILLabel condLabel in (ILLabel[])condBranch.Operand) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier);
}
foreach(ILLabel condLabel in (ILLabel[])condBranch.Operand) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
ILBlock caseBlock = new ILBlock() {
EntryGoto = new ILExpression(ILCode.Br, condLabel)
};
if (condTarget != null && !frontiers.Contains(condTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, condTarget));
}
ilSwitch.CaseBlocks.Add(caseBlock);
}
// The labels will not be used - kill them
condBranch.Operand = null;
result.Add(new ILBasicBlock() {
EntryLabel = block.EntryLabel, // Keep the entry label
Body = { ilSwitch }
});
scope.Remove(node);
}
// Two-way branch
ILCondition ilCond;
HashSet<ControlFlowNode> matchedNodes;
ILLabel condEntryLabel;
if (TryMatchCondition(scope, new ControlFlowNode[] {}, node, out ilCond, out matchedNodes, out condEntryLabel)) {
// The branch labels will not be used - kill them
foreach(ILExpression expr in ilCond.Condition.GetSelfAndChildrenRecursive<ILExpression>()) {
if (expr.GetBranchTargets().Any()) {
expr.Operand = null;
}
}
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue((ILLabel)ilCond.TrueBlock.EntryGoto.Operand, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue((ILLabel)ilCond.FalseBlock.EntryGoto.Operand, out falseTarget);
// Pull in the conditional code
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (trueTarget != null)
frontiers.UnionWith(trueTarget.DominanceFrontier);
if (falseTarget != null)
frontiers.UnionWith(falseTarget.DominanceFrontier);
if (trueTarget != null && !frontiers.Contains(trueTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
ilCond.TrueBlock.Body.AddRange(FindConditions(content, trueTarget));
}
if (falseTarget != null && !frontiers.Contains(falseTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
ilCond.FalseBlock.Body.AddRange(FindConditions(content, falseTarget));
}
result.Add(new ILBasicBlock() {
EntryLabel = condEntryLabel, // Keep the entry label
Body = { ilCond }
});
scope.ExceptWith(matchedNodes);
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node)) {
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// Using the dominator tree should ensure we find the the widest loop first
foreach(var child in node.DominatorTreeChildren) {
agenda.Add(child);
}
}
// Add whatever is left
foreach(var node in scope) {
result.Add((ILNode)node.UserData);
}
return result;
}
private List <ILVariable> PreprocessorCheckUninitializedLocalVarsBranch(ILBlock branch, List <ILVariable> initializedVars)
{
List <ILVariable> result = new List <ILVariable>(initializedVars);
foreach (ILNode node in branch.Body)
{
if (node is ILExpression)
{
PreprocessorCheckUninitializedLocalVarsExpression((ILExpression)node, result);
}
else if (node is ILBlock)
{
result = PreprocessorCheckUninitializedLocalVarsBranch((ILBlock)node, result);
}
else if (node is ILTryCatchBlock)
{
ILTryCatchBlock block = (ILTryCatchBlock)node;
List <ILVariable> newResult = new List <ILVariable>(result);
if (block.TryBlock != null)
{
newResult = newResult.Union(PreprocessorCheckUninitializedLocalVarsBranch(block.TryBlock, result)).ToList();
}
if (block.FaultBlock != null)
{
newResult = newResult.Union(PreprocessorCheckUninitializedLocalVarsBranch(block.FaultBlock, result)).ToList();
}
if (block.FinallyBlock != null)
{
newResult = newResult.Union(PreprocessorCheckUninitializedLocalVarsBranch(block.FinallyBlock, result)).ToList();
}
if (block.CatchBlocks != null)
{
foreach (ILTryCatchBlock.CatchBlock c in block.CatchBlocks)
{
newResult = newResult.Union(PreprocessorCheckUninitializedLocalVarsBranch(c, result)).ToList();
}
}
result = newResult;
}
else if (node is ILWhileLoop)
{
PreprocessorCheckUninitializedLocalVarsExpression(((ILWhileLoop)node).Condition, result);
result = PreprocessorCheckUninitializedLocalVarsBranch(((ILWhileLoop)node).BodyBlock, result);
}
else if (node is ILCondition)
{
ILCondition cond = (ILCondition)node;
PreprocessorCheckUninitializedLocalVarsExpression(cond.Condition, result);
List <ILVariable> fromTrue = PreprocessorCheckUninitializedLocalVarsBranch(cond.TrueBlock, result);
List <ILVariable> fromFalse = PreprocessorCheckUninitializedLocalVarsBranch(cond.FalseBlock, result);
result = fromTrue.Union(fromFalse).ToList();
}
else if (node is ILSwitch)
{
ILSwitch sw = (ILSwitch)node;
PreprocessorCheckUninitializedLocalVarsExpression(sw.Condition, result);
List <ILVariable> newResult = new List <ILVariable>(result);
foreach (var cas in sw.CaseBlocks)
{
newResult = newResult.Union(PreprocessorCheckUninitializedLocalVarsBranch(cas, result)).ToList();
}
result = newResult;
}
}
return(result);
}
/// <summary>
/// Get the first expression to be excecuted if the instruction pointer is at the start of the given node.
/// Try blocks may not be entered in any way. If possible, the try block is returned as the node to be executed.
/// </summary>
ILNode Enter(ILNode node, HashSet <ILNode> visitedNodes)
{
if (node == null)
{
throw new ArgumentNullException();
}
if (!visitedNodes.Add(node))
{
return(null); // Infinite loop
}
ILLabel label = node as ILLabel;
if (label != null)
{
return(Exit(label, visitedNodes));
}
ILExpression expr = node as ILExpression;
if (expr != null)
{
if (expr.Code == GMCode.B)
{
ILLabel target = (ILLabel)expr.Operand;
return(Enter(target, visitedNodes));
}
else if (expr.Code == GMCode.BadOp || expr.Code == GMCode.Constant || expr.Code == GMCode.Var)
{
return(Exit(expr, visitedNodes));
}
else if (expr.Code == GMCode.LoopOrSwitchBreak)
{
ILNode breakBlock = GetParents(expr).First(n => n is ILWhileLoop || n is ILSwitch || n is ILWithStatement);
return(Exit(breakBlock, new HashSet <ILNode>()
{
expr
}));
}
else if (expr.Code == GMCode.LoopContinue)
{
ILNode continueBlock = GetParents(expr).First(n => n is ILWhileLoop || n is ILWithStatement);
return(Enter(continueBlock, new HashSet <ILNode>()
{
expr
}));
}
else
{
return(expr);
}
}
ILBlock block = node as ILBlock;
if (block != null)
{
if (block.EntryGoto != null)
{
return(Enter(block.EntryGoto, visitedNodes));
}
else if (block.Body.Count > 0)
{
return(Enter(block.Body[0], visitedNodes));
}
else
{
return(Exit(block, visitedNodes));
}
}
ILCondition cond = node as ILCondition;
if (cond != null)
{
return(cond.Condition);
}
ILWhileLoop loop = node as ILWhileLoop;
if (loop != null)
{
if (loop.Condition != null)
{
return(loop.Condition);
}
else
{
return(Enter(loop.Body, visitedNodes));
}
}
ILSwitch ilSwitch = node as ILSwitch;
if (ilSwitch != null)
{
return(ilSwitch.Condition);
}
throw new NotSupportedException(node.GetType().ToString());
}
/// <summary>
/// Get the first expression to be excecuted if the instruction pointer is at the start of the given node.
/// Try blocks may not be entered in any way. If possible, the try block is returned as the node to be executed.
/// </summary>
ILNode Enter(ILNode node, HashSet <ILNode> visitedNodes)
{
if (node == null)
{
throw new ArgumentNullException();
}
if (!visitedNodes.Add(node))
{
return(null); // Infinite loop
}
ILLabel label = node as ILLabel;
if (label != null)
{
return(Exit(label, visitedNodes));
}
ILExpression expr = node as ILExpression;
if (expr != null)
{
if (expr.Code == ILCode.Br || expr.Code == ILCode.Leave)
{
ILLabel target = (ILLabel)expr.Operand;
// Early exit - same try-block
if (GetParents(expr).OfType <ILTryCatchBlock>().FirstOrDefault() == GetParents(target).OfType <ILTryCatchBlock>().FirstOrDefault())
{
return(Enter(target, visitedNodes));
}
// Make sure we are not entering any try-block
var srcTryBlocks = GetParents(expr).OfType <ILTryCatchBlock>().Reverse().ToList();
var dstTryBlocks = GetParents(target).OfType <ILTryCatchBlock>().Reverse().ToList();
// Skip blocks that we are already in
int i = 0;
while (i < srcTryBlocks.Count && i < dstTryBlocks.Count && srcTryBlocks[i] == dstTryBlocks[i])
{
i++;
}
if (i == dstTryBlocks.Count)
{
return(Enter(target, visitedNodes));
}
else
{
ILTryCatchBlock dstTryBlock = dstTryBlocks[i];
// Check that the goto points to the start
ILTryCatchBlock current = dstTryBlock;
while (current != null)
{
foreach (ILNode n in current.TryBlock.Body)
{
if (n is ILLabel)
{
if (n == target)
{
return(dstTryBlock);
}
}
else if (!n.Match(ILCode.Nop))
{
current = n as ILTryCatchBlock;
break;
}
}
}
return(null);
}
}
else if (expr.Code == ILCode.Nop)
{
return(Exit(expr, visitedNodes));
}
else if (expr.Code == ILCode.LoopOrSwitchBreak)
{
ILNode breakBlock = GetParents(expr).First(n => n is ILWhileLoop || n is ILSwitch);
return(Exit(breakBlock, new HashSet <ILNode>()
{
expr
}));
}
else if (expr.Code == ILCode.LoopContinue)
{
ILNode continueBlock = GetParents(expr).First(n => n is ILWhileLoop);
return(Enter(continueBlock, new HashSet <ILNode>()
{
expr
}));
}
else
{
return(expr);
}
}
ILBlock block = node as ILBlock;
if (block != null)
{
if (block.EntryGoto != null)
{
return(Enter(block.EntryGoto, visitedNodes));
}
else if (block.Body.Count > 0)
{
return(Enter(block.Body[0], visitedNodes));
}
else
{
return(Exit(block, visitedNodes));
}
}
ILCondition cond = node as ILCondition;
if (cond != null)
{
return(cond.Condition);
}
ILWhileLoop loop = node as ILWhileLoop;
if (loop != null)
{
if (loop.Condition != null)
{
return(loop.Condition);
}
else
{
return(Enter(loop.BodyBlock, visitedNodes));
}
}
ILTryCatchBlock tryCatch = node as ILTryCatchBlock;
if (tryCatch != null)
{
return(tryCatch);
}
ILSwitch ilSwitch = node as ILSwitch;
if (ilSwitch != null)
{
return(ilSwitch.Condition);
}
throw new NotSupportedException(node.GetType().ToString());
}
protected virtual ILSwitch VisitSwitch(ILSwitch switchStatement)
{
foreach (var child in switchStatement.GetChildren())
Visit(child);
return switchStatement;
}
List<ILNode> FindConditions(HashSet<ControlFlowNode> nodes, ControlFlowNode entryNode)
{
List<ILNode> result = new List<ILNode>();
Queue<ControlFlowNode> agenda = new Queue<ControlFlowNode>();
agenda.Enqueue(entryNode);
while(agenda.Count > 0) {
ControlFlowNode node = agenda.Dequeue();
// Find a block that represents a simple condition
if (nodes.Contains(node)) {
ILMoveableBlock block = node.UserData as ILMoveableBlock;
if (block != null && block.Body.Count == 3) {
ILLabel label = block.Body[0] as ILLabel;
ILExpression condBranch = block.Body[1] as ILExpression;
ILExpression statBranch = block.Body[2] as ILExpression;
// Switch
if (label != null &&
condBranch != null && condBranch.Operand is ILLabel[] && condBranch.Arguments.Count > 0 &&
statBranch != null && statBranch.Operand is ILLabel && statBranch.Arguments.Count == 0)
{
ILSwitch ilSwitch = new ILSwitch() { Condition = condBranch };
// Replace the two branches with a conditional structure - this preserves the node label
block.Body.Remove(condBranch);
block.Body.Remove(statBranch);
block.Body.Add(ilSwitch);
ControlFlowNode statTarget = null;
labelToCfNode.TryGetValue((ILLabel)statBranch.Operand, out statTarget);
// Pull in the conditional code
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (statTarget != null)
frontiers.UnionWith(statTarget.DominanceFrontier);
foreach(ILLabel condLabel in (ILLabel[])condBranch.Operand) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier);
}
foreach(ILLabel condLabel in (ILLabel[])condBranch.Operand) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
ILBlock caseBlock = new ILBlock() { EntryPoint = condLabel };
if (condTarget != null && !frontiers.Contains(condTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(nodes, condTarget);
nodes.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, condTarget));
}
ilSwitch.CaseBlocks.Add(caseBlock);
}
// The labels will not be used - kill them
condBranch.Operand = null;
result.Add(block);
nodes.Remove(node);
}
// Two-way branch
if (label != null &&
condBranch != null && condBranch.Operand is ILLabel && condBranch.Arguments.Count > 0 &&
statBranch != null && statBranch.Operand is ILLabel && statBranch.Arguments.Count == 0)
{
ControlFlowNode statTarget = null;
labelToCfNode.TryGetValue((ILLabel)statBranch.Operand, out statTarget);
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue((ILLabel)condBranch.Operand, out condTarget);
ILCondition condition = new ILCondition() {
Condition = condBranch,
TrueBlock = new ILBlock() { EntryPoint = (ILLabel)condBranch.Operand },
FalseBlock = new ILBlock() { EntryPoint = (ILLabel)statBranch.Operand }
};
// Replace the two branches with a conditional structure - this preserves the node label
block.Body.Remove(condBranch);
block.Body.Remove(statBranch);
block.Body.Add(condition);
// Pull in the conditional code
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (statTarget != null)
frontiers.UnionWith(statTarget.DominanceFrontier);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier);
if (condTarget != null && !frontiers.Contains(condTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(nodes, condTarget);
nodes.ExceptWith(content);
condition.TrueBlock.Body.AddRange(FindConditions(content, condTarget));
}
if (statTarget != null && !frontiers.Contains(statTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(nodes, statTarget);
nodes.ExceptWith(content);
condition.FalseBlock.Body.AddRange(FindConditions(content, statTarget));
}
// The label will not be used - kill it
condBranch.Operand = null;
result.Add(block);
nodes.Remove(node);
}
}
// Add the node now so that we have good ordering
if (nodes.Contains(node)) {
result.Add((ILNode)node.UserData);
nodes.Remove(node);
}
}
// Using the dominator tree should ensure we find the the widest loop first
foreach(var child in node.DominatorTreeChildren) {
agenda.Enqueue(child);
}
}
// Add whatever is left
foreach(var node in nodes) {
result.Add((ILNode)node.UserData);
}
return result;
}
List <ILNode> FindConditions(HashSet <ControlFlowNode> scope, ControlFlowNode entryNode)
{
List <ILNode> result = new List <ILNode>();
// Do not modify entry data
scope = new HashSet <ControlFlowNode>(scope);
Stack <ControlFlowNode> agenda = new Stack <ControlFlowNode>();
agenda.Push(entryNode);
while (agenda.Count > 0)
{
ControlFlowNode node = agenda.Pop();
// Find a block that represents a simple condition
if (scope.Contains(node))
{
ILBasicBlock block = (ILBasicBlock)node.UserData;
{
IList <ILExpression> conditions;
ILLabel fallLabel;
// Switch
FakeSwitch fswitch;
if (block.MatchLastAndBr(GMCode.Switch, out fswitch, out conditions, out fallLabel))
{
ILSwitch ilSwitch = new ILSwitch()
{
Condition = fswitch.SwitchExpression
};
block.Body[block.Body.Count - 2] = ilSwitch; // replace it, nothing else needs to be done!
result.Add(block); // except add it to the result, DOLT
scope.RemoveOrThrow(node); // Remove the item so that it is not picked up as content
// Pull in code of cases
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue(fallLabel, out fallTarget);
HashSet <ControlFlowNode> frontiers = new HashSet <ControlFlowNode>();
if (fallTarget != null)
{
frontiers.UnionWith(fallTarget.DominanceFrontier.Except(new[] { fallTarget }));
}
foreach (ILLabel condLabel in fswitch.CaseExpressions.Select(x => x.Value))
{
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
{
frontiers.UnionWith(condTarget.DominanceFrontier.Except(new[] { condTarget }));
}
}
for (int i = 0; i < fswitch.CaseExpressions.Count; i++)
{
ILLabel condLabel = fswitch.CaseExpressions[i].Value;
// Find or create new case block
ILSwitch.ILCase caseBlock = ilSwitch.Cases.FirstOrDefault(b => b.EntryGoto.Operand == condLabel);
if (caseBlock == null)
{
caseBlock = new ILSwitch.ILCase()
{
Values = new List <ILExpression>(),
EntryGoto = new ILExpression(GMCode.B, condLabel)
};
ilSwitch.Cases.Add(caseBlock);
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null && !frontiers.Contains(condTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, condTarget))
{
caseBlock.Body.Add(con);
}
// caseBlock.Body.AddRange(FindConditions(content, condTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body =
{
ILLabel.Generate("SwitchBreak", (int)nextLabelIndex++),
new ILExpression(GMCode.LoopOrSwitchBreak, null)
}
});
}
}
caseBlock.Values.Add(fswitch.CaseExpressions[i].Key);
}
// Heuristis to determine if we want to use fallthough as default case
if (fallTarget != null && !frontiers.Contains(fallTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, fallTarget);
if (content.Any())
{
var caseBlock = new ILSwitch.ILCase()
{
EntryGoto = new ILExpression(GMCode.B, fallLabel)
};
ilSwitch.Cases.Add(caseBlock);
block.Body.RemoveTail(GMCode.B);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, fallTarget))
{
caseBlock.Body.Add(con);
}
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body =
{
ILLabel.Generate("SwitchBreak", (int)nextLabelIndex++),
new ILExpression(GMCode.LoopOrSwitchBreak, null)
}
});
}
}
}
// Debug.Assert((block.Body.First() as ILLabel).Name != "L1938");
// Two-way branch
ILLabel trueLabel;
ILLabel falseLabel;
IList <ILExpression> condExprs;
if (block.MatchLastAndBr(GMCode.Bt, out trueLabel, out condExprs, out falseLabel) && // be sure to invert this condition
condExprs.Count > 0) // its resolved
{
ILExpression condExpr = condExprs[0];
IList <ILNode> body = block.Body;
// this is a simple condition, skip anything short curiket for now
// Match a condition patern
// Convert the brtrue to ILCondition
ILCondition ilCond = new ILCondition()
{
Condition = condExpr, //code == GMCode.Bf ? condExpr : condExpr.NegateCondition(),
TrueBlock = new ILBlock()
{
EntryGoto = new ILExpression(GMCode.B, trueLabel)
},
FalseBlock = new ILBlock()
{
EntryGoto = new ILExpression(GMCode.B, falseLabel)
}
};
block.Body.RemoveTail(GMCode.Bt, GMCode.B);
block.Body.Add(ilCond);
result.Add(block);
// Remove the item immediately so that it is not picked up as content
scope.RemoveOrThrow(node);
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue(trueLabel, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue(falseLabel, out falseTarget);
// Pull in the conditional code
if (trueTarget != null && HasSingleEdgeEnteringBlock(trueTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, trueTarget))
{
ilCond.TrueBlock.Body.Add(con);
}
}
if (falseTarget != null && HasSingleEdgeEnteringBlock(falseTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, falseTarget))
{
ilCond.FalseBlock.Body.Add(con);
}
}
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node))
{
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// depth-first traversal of dominator tree
for (int i = node.DominatorTreeChildren.Count - 1; i >= 0; i--)
{
agenda.Push(node.DominatorTreeChildren[i]);
}
}
// Add whatever is left
foreach (var node in scope)
{
result.Add((ILNode)node.UserData);
}
return(result);
}
List<ILNode> FindConditions(HashSet<ControlFlowNode> scope, ControlFlowNode entryNode)
{
List<ILNode> result = new List<ILNode>();
// Do not modify entry data
scope = new HashSet<ControlFlowNode>(scope);
Stack<ControlFlowNode> agenda = new Stack<ControlFlowNode>();
agenda.Push(entryNode);
while (agenda.Count > 0)
{
ControlFlowNode node = agenda.Pop();
// Find a block that represents a simple condition
if (scope.Contains(node))
{
ILBasicBlock block = (ILBasicBlock)node.UserData;
{
IList<ILExpression> conditions;
ILLabel fallLabel;
// Switch
FakeSwitch fswitch;
if (block.MatchLastAndBr(GMCode.Switch, out fswitch, out conditions, out fallLabel))
{
ILSwitch ilSwitch = new ILSwitch() { Condition = fswitch.SwitchExpression };
block.Body[block.Body.Count - 2] = ilSwitch; // replace it, nothing else needs to be done!
result.Add(block); // except add it to the result, DOLT
scope.RemoveOrThrow(node);// Remove the item so that it is not picked up as content
// Pull in code of cases
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue(fallLabel, out fallTarget);
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (fallTarget != null)
frontiers.UnionWith(fallTarget.DominanceFrontier.Except(new[] { fallTarget }));
foreach (ILLabel condLabel in fswitch.CaseExpressions.Select(x => x.Value))
{
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier.Except(new[] { condTarget }));
}
for (int i = 0; i < fswitch.CaseExpressions.Count; i++)
{
ILLabel condLabel = fswitch.CaseExpressions[i].Value;
// Find or create new case block
ILSwitch.ILCase caseBlock = ilSwitch.Cases.FirstOrDefault(b => b.EntryGoto.Operand == condLabel);
if (caseBlock == null)
{
caseBlock = new ILSwitch.ILCase()
{
Values = new List<ILExpression>(),
EntryGoto = new ILExpression(GMCode.B, condLabel)
};
ilSwitch.Cases.Add(caseBlock);
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null && !frontiers.Contains(condTarget))
{
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, condTarget)) caseBlock.Body.Add(con);
// caseBlock.Body.AddRange(FindConditions(content, condTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body = {
ILLabel.Generate("SwitchBreak" ,(int)nextLabelIndex++),
new ILExpression(GMCode.LoopOrSwitchBreak, null)
}
});
}
}
caseBlock.Values.Add(fswitch.CaseExpressions[i].Key);
}
// Heuristis to determine if we want to use fallthough as default case
if (fallTarget != null && !frontiers.Contains(fallTarget))
{
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, fallTarget);
if (content.Any())
{
var caseBlock = new ILSwitch.ILCase() { EntryGoto = new ILExpression(GMCode.B, fallLabel) };
ilSwitch.Cases.Add(caseBlock);
block.Body.RemoveTail(GMCode.B);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, fallTarget)) caseBlock.Body.Add(con);
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body = {
ILLabel.Generate("SwitchBreak" ,(int)nextLabelIndex++),
new ILExpression(GMCode.LoopOrSwitchBreak, null)
}
});
}
}
}
// Debug.Assert((block.Body.First() as ILLabel).Name != "L1938");
// Two-way branch
ILLabel trueLabel;
ILLabel falseLabel;
IList<ILExpression> condExprs;
if (block.MatchLastAndBr(GMCode.Bt, out trueLabel, out condExprs, out falseLabel) // be sure to invert this condition
&& condExprs.Count > 0) // its resolved
{
ILExpression condExpr = condExprs[0];
IList<ILNode> body = block.Body;
// this is a simple condition, skip anything short curiket for now
// Match a condition patern
// Convert the brtrue to ILCondition
ILCondition ilCond = new ILCondition()
{
Condition = condExpr, //code == GMCode.Bf ? condExpr : condExpr.NegateCondition(),
TrueBlock = new ILBlock() { EntryGoto = new ILExpression(GMCode.B, trueLabel) },
FalseBlock = new ILBlock() { EntryGoto = new ILExpression(GMCode.B, falseLabel) }
};
block.Body.RemoveTail(GMCode.Bt, GMCode.B);
block.Body.Add(ilCond);
result.Add(block);
// Remove the item immediately so that it is not picked up as content
scope.RemoveOrThrow(node);
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue(trueLabel, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue(falseLabel, out falseTarget);
// Pull in the conditional code
if (trueTarget != null && HasSingleEdgeEnteringBlock(trueTarget))
{
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, trueTarget)) ilCond.TrueBlock.Body.Add(con);
}
if (falseTarget != null && HasSingleEdgeEnteringBlock(falseTarget))
{
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
foreach (var con in FindConditions(content, falseTarget)) ilCond.FalseBlock.Body.Add(con);
}
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node))
{
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// depth-first traversal of dominator tree
for (int i = node.DominatorTreeChildren.Count - 1; i >= 0; i--)
{
agenda.Push(node.DominatorTreeChildren[i]);
}
}
// Add whatever is left
foreach (var node in scope)
{
result.Add((ILNode)node.UserData);
}
return result;
}
List<ILNode> FindConditions(HashSet<ControlFlowNode> scope, ControlFlowNode entryNode)
{
List<ILNode> result = new List<ILNode>();
// Do not modify entry data
scope = new HashSet<ControlFlowNode>(scope);
HashSet<ControlFlowNode> agenda = new HashSet<ControlFlowNode>();
agenda.Add(entryNode);
while(agenda.Any()) {
ControlFlowNode node = agenda.First();
// Attempt for a good order
while(agenda.Contains(node.ImmediateDominator)) {
node = node.ImmediateDominator;
}
agenda.Remove(node);
// Find a block that represents a simple condition
if (scope.Contains(node)) {
ILBasicBlock block = node.UserData as ILBasicBlock;
if (block != null && block.Body.Count == 1) {
ILExpression condBranch = block.Body[0] as ILExpression;
// Switch
if (condBranch != null && condBranch.Operand is ILLabel[] && condBranch.Arguments.Count > 0) {
ILLabel[] caseLabels = (ILLabel[])condBranch.Operand;
// The labels will not be used - kill them
condBranch.Operand = null;
ILSwitch ilSwitch = new ILSwitch() {
Condition = condBranch,
DefaultGoto = block.FallthoughGoto
};
result.Add(new ILBasicBlock() {
EntryLabel = block.EntryLabel, // Keep the entry label
Body = { ilSwitch }
});
// Remove the item so that it is not picked up as content
if (!scope.Remove(node))
throw new Exception("Item is not in set");
// Pull in code of cases
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue((ILLabel)block.FallthoughGoto.Operand, out fallTarget);
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (fallTarget != null)
frontiers.UnionWith(fallTarget.DominanceFrontier);
foreach(ILLabel condLabel in caseLabels) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier);
}
foreach(ILLabel condLabel in caseLabels) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
ILBlock caseBlock = new ILBlock() {
EntryGoto = new ILExpression(ILCode.Br, condLabel)
};
if (condTarget != null && !frontiers.Contains(condTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, condTarget));
}
ilSwitch.CaseBlocks.Add(caseBlock);
}
}
// Two-way branch
ILExpression branchExpr = null;
ILLabel trueLabel = null;
ILLabel falseLabel = null;
if(IsConditionalBranch(block, ref branchExpr, ref trueLabel, ref falseLabel)) {
// The branch label will not be used - kill it
branchExpr.Operand = null;
// Convert the basic block to ILCondition
ILCondition ilCond = new ILCondition() {
Condition = branchExpr,
TrueBlock = new ILBlock() { EntryGoto = new ILExpression(ILCode.Br, trueLabel) },
FalseBlock = new ILBlock() { EntryGoto = new ILExpression(ILCode.Br, falseLabel) }
};
result.Add(new ILBasicBlock() {
EntryLabel = block.EntryLabel, // Keep the entry label
Body = { ilCond }
});
// Remove the item immediately so that it is not picked up as content
if (!scope.Remove(node))
throw new Exception("Item is not in set");
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue(trueLabel, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue(falseLabel, out falseTarget);
// Pull in the conditional code
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (trueTarget != null)
frontiers.UnionWith(trueTarget.DominanceFrontier);
if (falseTarget != null)
frontiers.UnionWith(falseTarget.DominanceFrontier);
if (trueTarget != null && !frontiers.Contains(trueTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
ilCond.TrueBlock.Body.AddRange(FindConditions(content, trueTarget));
}
if (falseTarget != null && !frontiers.Contains(falseTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
ilCond.FalseBlock.Body.AddRange(FindConditions(content, falseTarget));
}
if (scope.Count == 0) {
// We have removed the whole scope - eliminte one of the condition bodies
int trueSize = ilCond.TrueBlock.GetSelfAndChildrenRecursive<ILNode>().Count();
int falseSize = ilCond.FalseBlock.GetSelfAndChildrenRecursive<ILNode>().Count();
// The block are protected
Debug.Assert(ilCond.TrueBlock.EntryGoto != null);
Debug.Assert(ilCond.FalseBlock.EntryGoto != null);
if (falseSize > trueSize) {
// Move the false body out
result.AddRange(ilCond.FalseBlock.Body);
ilCond.FalseBlock.Body.Clear();
} else {
// Move the true body out
result.AddRange(ilCond.TrueBlock.Body);
ilCond.TrueBlock.Body.Clear();
}
}
// If true body is empty, swap bodies.
// Might happend because there was not any to start with or we moved it out.
if (ilCond.TrueBlock.Body.Count == 0 && ilCond.FalseBlock.Body.Count > 0) {
ILBlock tmp = ilCond.TrueBlock;
ilCond.TrueBlock = ilCond.FalseBlock;
ilCond.FalseBlock = tmp;
ilCond.Condition = new ILExpression(ILCode.LogicNot, null, ilCond.Condition);
}
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node)) {
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// Using the dominator tree should ensure we find the the widest loop first
foreach(var child in node.DominatorTreeChildren) {
agenda.Add(child);
}
}
// Add whatever is left
foreach(var node in scope) {
result.Add((ILNode)node.UserData);
}
return result;
}
List <ILNode> FindConditions(HashSet <ControlFlowNode> scope, ControlFlowNode entryNode)
{
List <ILNode> result = new List <ILNode>();
// Do not modify entry data
scope = new HashSet <ControlFlowNode>(scope);
Stack <ControlFlowNode> agenda = new Stack <ControlFlowNode>();
agenda.Push(entryNode);
while (agenda.Count > 0)
{
ControlFlowNode node = agenda.Pop();
// Find a block that represents a simple condition
if (scope.Contains(node))
{
ILBasicBlock block = (ILBasicBlock)node.UserData;
{
// Switch
ILLabel[] caseLabels;
ILExpression switchArg;
ILLabel fallLabel;
if (block.MatchLastAndBr(ILCode.Switch, out caseLabels, out switchArg, out fallLabel))
{
// Replace the switch code with ILSwitch
ILSwitch ilSwitch = new ILSwitch()
{
Condition = switchArg
};
block.Body.RemoveTail(ILCode.Switch, ILCode.Br);
block.Body.Add(ilSwitch);
block.Body.Add(new ILExpression(ILCode.Br, fallLabel));
result.Add(block);
// Remove the item so that it is not picked up as content
scope.RemoveOrThrow(node);
// Find the switch offset
int addValue = 0;
List <ILExpression> subArgs;
if (ilSwitch.Condition.Match(ILCode.Sub, out subArgs) && subArgs[1].Match(ILCode.Ldc_I4, out addValue))
{
ilSwitch.Condition = subArgs[0];
}
// Pull in code of cases
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue(fallLabel, out fallTarget);
HashSet <ControlFlowNode> frontiers = new HashSet <ControlFlowNode>();
if (fallTarget != null)
{
frontiers.UnionWith(fallTarget.DominanceFrontier.Except(new [] { fallTarget }));
}
foreach (ILLabel condLabel in caseLabels)
{
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
{
frontiers.UnionWith(condTarget.DominanceFrontier.Except(new [] { condTarget }));
}
}
for (int i = 0; i < caseLabels.Length; i++)
{
ILLabel condLabel = caseLabels[i];
// Find or create new case block
ILSwitch.CaseBlock caseBlock = ilSwitch.CaseBlocks.FirstOrDefault(b => b.EntryGoto.Operand == condLabel);
if (caseBlock == null)
{
caseBlock = new ILSwitch.CaseBlock()
{
Values = new List <int>(),
EntryGoto = new ILExpression(ILCode.Br, condLabel)
};
ilSwitch.CaseBlocks.Add(caseBlock);
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null && !frontiers.Contains(condTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, condTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body =
{
new ILLabel()
{
Name = "SwitchBreak_" + (nextLabelIndex++)
},
new ILExpression(ILCode.LoopOrSwitchBreak, null)
}
});
}
}
caseBlock.Values.Add(i + addValue);
}
// Heuristis to determine if we want to use fallthough as default case
if (fallTarget != null && !frontiers.Contains(fallTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, fallTarget);
if (content.Any())
{
var caseBlock = new ILSwitch.CaseBlock()
{
EntryGoto = new ILExpression(ILCode.Br, fallLabel)
};
ilSwitch.CaseBlocks.Add(caseBlock);
block.Body.RemoveTail(ILCode.Br);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, fallTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock()
{
Body =
{
new ILLabel()
{
Name = "SwitchBreak_" + (nextLabelIndex++)
},
new ILExpression(ILCode.LoopOrSwitchBreak, null)
}
});
}
}
}
// Two-way branch
ILExpression condExpr;
ILLabel trueLabel;
ILLabel falseLabel;
if (block.MatchLastAndBr(ILCode.Brtrue, out trueLabel, out condExpr, out falseLabel))
{
// Swap bodies since that seems to be the usual C# order
ILLabel temp = trueLabel;
trueLabel = falseLabel;
falseLabel = temp;
condExpr = new ILExpression(ILCode.LogicNot, null, condExpr);
// Convert the brtrue to ILCondition
ILCondition ilCond = new ILCondition()
{
Condition = condExpr,
TrueBlock = new ILBlock()
{
EntryGoto = new ILExpression(ILCode.Br, trueLabel)
},
FalseBlock = new ILBlock()
{
EntryGoto = new ILExpression(ILCode.Br, falseLabel)
}
};
block.Body.RemoveTail(ILCode.Brtrue, ILCode.Br);
block.Body.Add(ilCond);
result.Add(block);
// Remove the item immediately so that it is not picked up as content
scope.RemoveOrThrow(node);
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue(trueLabel, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue(falseLabel, out falseTarget);
// Pull in the conditional code
if (trueTarget != null && HasSingleEdgeEnteringBlock(trueTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
ilCond.TrueBlock.Body.AddRange(FindConditions(content, trueTarget));
}
if (falseTarget != null && HasSingleEdgeEnteringBlock(falseTarget))
{
HashSet <ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
ilCond.FalseBlock.Body.AddRange(FindConditions(content, falseTarget));
}
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node))
{
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// depth-first traversal of dominator tree
for (int i = node.DominatorTreeChildren.Count - 1; i >= 0; i--)
{
agenda.Push(node.DominatorTreeChildren[i]);
}
}
// Add whatever is left
foreach (var node in scope)
{
result.Add((ILNode)node.UserData);
}
return(result);
}
public JSSwitchStatement TranslateNode(ILSwitch swtch)
{
var condition = TranslateNode(swtch.Condition);
var conditionType = condition.GetExpectedType(TypeSystem);
var result = new JSSwitchStatement(condition);
Blocks.Push(result);
result.Cases.AddRange(
(from cb in swtch.CaseBlocks select TranslateNode(cb, conditionType))
);
Blocks.Pop();
return result;
}
public Dictionary <int, EventRegistration[]> DecompileEventMappings(string fullTypeName)
{
var result = new Dictionary <int, EventRegistration[]>();
TypeDefinition type = this.assembly.MainModule.GetType(fullTypeName);
if (type == null)
{
return(result);
}
MethodDefinition def = null;
foreach (var method in type.Methods)
{
if (method.Name == "System.Windows.Markup.IComponentConnector.Connect")
{
def = method;
break;
}
}
if (def == null)
{
return(result);
}
// decompile method and optimize the switch
ILBlock ilMethod = new ILBlock();
ILAstBuilder astBuilder = new ILAstBuilder();
ilMethod.Body = astBuilder.Build(def, true);
ILAstOptimizer optimizer = new ILAstOptimizer();
var context = new DecompilerContext(type.Module)
{
CurrentMethod = def, CurrentType = type
};
optimizer.Optimize(context, ilMethod, ILAstOptimizationStep.RemoveRedundantCode3);
ILSwitch ilSwitch = ilMethod.Body.OfType <ILSwitch>().FirstOrDefault();
ILCondition condition = ilMethod.Body.OfType <ILCondition>().FirstOrDefault();
if (ilSwitch != null)
{
foreach (var caseBlock in ilSwitch.CaseBlocks)
{
if (caseBlock.Values == null)
{
continue;
}
var events = FindEvents(caseBlock);
foreach (int id in caseBlock.Values)
{
result.Add(id, events);
}
}
}
else if (condition != null)
{
result.Add(1, FindEvents(condition.FalseBlock));
}
return(result);
}
/// <summary>
/// Responsible for detecting switch cases with values that are actually also the default case
/// </summary>
static void AnointDefaultSwitchCases (ILSwitch swtch) {
var defaultCase = swtch.CaseBlocks.FirstOrDefault((cse) => cse.IsDefault);
if (defaultCase == null)
return;
var lastBlock = defaultCase.Body.LastOrDefault() as ILBasicBlock;
if (
(lastBlock != null) &&
(lastBlock.Body.Count == 2) &&
(lastBlock.Body[0] is ILLabel) &&
(lastBlock.Body[1] is ILExpression) &&
(((ILExpression)lastBlock.Body[1]).Code == ILCode.LoopOrSwitchBreak)
) {
// This is a delegating default case. Ensure the target is another case in this switch block.
var targetCase = swtch.CaseBlocks.FirstOrDefault(
(cse) => (
(cse.EntryGoto.Operand == defaultCase.EntryGoto.Operand) &&
(cse != defaultCase)
)
);
if (targetCase != null) {
// The target is another case in this switch block, so fold the current case into that one.
swtch.CaseBlocks.Remove(defaultCase);
targetCase.IsDefault = true;
}
}
}
List<ILNode> FindConditions(HashSet<ControlFlowNode> scope, ControlFlowNode entryNode)
{
List<ILNode> result = new List<ILNode>();
// Do not modify entry data
scope = new HashSet<ControlFlowNode>(scope);
Stack<ControlFlowNode> agenda = new Stack<ControlFlowNode>();
agenda.Push(entryNode);
while(agenda.Count > 0) {
ControlFlowNode node = agenda.Pop();
// Find a block that represents a simple condition
if (scope.Contains(node)) {
ILBasicBlock block = (ILBasicBlock)node.UserData;
{
// Switch
ILLabel[] caseLabels;
ILExpression switchArg;
ILLabel fallLabel;
if (block.MatchLastAndBr(ILCode.Switch, out caseLabels, out switchArg, out fallLabel)) {
// Replace the switch code with ILSwitch
ILSwitch ilSwitch = new ILSwitch() { Condition = switchArg };
block.Body.RemoveTail(ILCode.Switch, ILCode.Br);
block.Body.Add(ilSwitch);
block.Body.Add(new ILExpression(ILCode.Br, fallLabel));
result.Add(block);
// Remove the item so that it is not picked up as content
scope.RemoveOrThrow(node);
// Find the switch offset
int addValue = 0;
List<ILExpression> subArgs;
if (ilSwitch.Condition.Match(ILCode.Sub, out subArgs) && subArgs[1].Match(ILCode.Ldc_I4, out addValue)) {
ilSwitch.Condition = subArgs[0];
}
// Pull in code of cases
ControlFlowNode fallTarget = null;
labelToCfNode.TryGetValue(fallLabel, out fallTarget);
HashSet<ControlFlowNode> frontiers = new HashSet<ControlFlowNode>();
if (fallTarget != null)
frontiers.UnionWith(fallTarget.DominanceFrontier.Except(new [] { fallTarget }));
foreach(ILLabel condLabel in caseLabels) {
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null)
frontiers.UnionWith(condTarget.DominanceFrontier.Except(new [] { condTarget }));
}
for (int i = 0; i < caseLabels.Length; i++) {
ILLabel condLabel = caseLabels[i];
// Find or create new case block
ILSwitch.CaseBlock caseBlock = ilSwitch.CaseBlocks.FirstOrDefault(b => b.EntryGoto.Operand == condLabel);
if (caseBlock == null) {
caseBlock = new ILSwitch.CaseBlock() {
Values = new List<int>(),
EntryGoto = new ILExpression(ILCode.Br, condLabel)
};
ilSwitch.CaseBlocks.Add(caseBlock);
ControlFlowNode condTarget = null;
labelToCfNode.TryGetValue(condLabel, out condTarget);
if (condTarget != null && !frontiers.Contains(condTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, condTarget);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, condTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock() {
Body = {
new ILLabel() { Name = "SwitchBreak_" + (nextLabelIndex++) },
new ILExpression(ILCode.LoopOrSwitchBreak, null)
}
});
}
}
caseBlock.Values.Add(i + addValue);
}
// Heuristis to determine if we want to use fallthough as default case
if (fallTarget != null && !frontiers.Contains(fallTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, fallTarget);
if (content.Any()) {
var caseBlock = new ILSwitch.CaseBlock() { EntryGoto = new ILExpression(ILCode.Br, fallLabel) };
ilSwitch.CaseBlocks.Add(caseBlock);
block.Body.RemoveTail(ILCode.Br);
scope.ExceptWith(content);
caseBlock.Body.AddRange(FindConditions(content, fallTarget));
// Add explicit break which should not be used by default, but the goto removal might decide to use it
caseBlock.Body.Add(new ILBasicBlock() {
Body = {
new ILLabel() { Name = "SwitchBreak_" + (nextLabelIndex++) },
new ILExpression(ILCode.LoopOrSwitchBreak, null)
}
});
}
}
}
// Two-way branch
ILExpression condExpr;
ILLabel trueLabel;
ILLabel falseLabel;
if(block.MatchLastAndBr(ILCode.Brtrue, out trueLabel, out condExpr, out falseLabel)) {
// Swap bodies since that seems to be the usual C# order
ILLabel temp = trueLabel;
trueLabel = falseLabel;
falseLabel = temp;
condExpr = new ILExpression(ILCode.LogicNot, null, condExpr);
// Convert the brtrue to ILCondition
ILCondition ilCond = new ILCondition() {
Condition = condExpr,
TrueBlock = new ILBlock() { EntryGoto = new ILExpression(ILCode.Br, trueLabel) },
FalseBlock = new ILBlock() { EntryGoto = new ILExpression(ILCode.Br, falseLabel) }
};
block.Body.RemoveTail(ILCode.Brtrue, ILCode.Br);
block.Body.Add(ilCond);
result.Add(block);
// Remove the item immediately so that it is not picked up as content
scope.RemoveOrThrow(node);
ControlFlowNode trueTarget = null;
labelToCfNode.TryGetValue(trueLabel, out trueTarget);
ControlFlowNode falseTarget = null;
labelToCfNode.TryGetValue(falseLabel, out falseTarget);
// Pull in the conditional code
if (trueTarget != null && HasSingleEdgeEnteringBlock(trueTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, trueTarget);
scope.ExceptWith(content);
ilCond.TrueBlock.Body.AddRange(FindConditions(content, trueTarget));
}
if (falseTarget != null && HasSingleEdgeEnteringBlock(falseTarget)) {
HashSet<ControlFlowNode> content = FindDominatedNodes(scope, falseTarget);
scope.ExceptWith(content);
ilCond.FalseBlock.Body.AddRange(FindConditions(content, falseTarget));
}
}
}
// Add the node now so that we have good ordering
if (scope.Contains(node)) {
result.Add((ILNode)node.UserData);
scope.Remove(node);
}
}
// depth-first traversal of dominator tree
for (int i = node.DominatorTreeChildren.Count - 1; i >= 0; i--) {
agenda.Push(node.DominatorTreeChildren[i]);
}
}
// Add whatever is left
foreach(var node in scope) {
result.Add((ILNode)node.UserData);
}
return result;
}
private void ProcessMethodDecencies(InterMethod method, ILNode node, List <InterGenericArgument> genericArgs)
{
if (node is ILBlock)
{
ILBlock block = node as ILBlock;
foreach (ILNode n in block.Body)
{
ProcessMethodDecencies(method, n, genericArgs);
}
}
else if (node is ILBasicBlock)
{
ILBasicBlock block = node as ILBasicBlock;
foreach (ILNode n in block.Body)
{
ProcessMethodDecencies(method, n, genericArgs);
}
}
else if (node is ILTryCatchBlock)
{
ILTryCatchBlock block = node as ILTryCatchBlock;
foreach (ILNode n in block.TryBlock.Body)
{
ProcessMethodDecencies(method, n, genericArgs);
}
if (block.FaultBlock != null)
{
foreach (ILNode n in block.FaultBlock.Body)
{
ProcessMethodDecencies(method, n, genericArgs);
}
}
if (block.FinallyBlock != null)
{
foreach (ILNode n in block.FinallyBlock.Body)
{
ProcessMethodDecencies(method, n, genericArgs);
}
}
foreach (var catchBlock in block.CatchBlocks)
{
((IResolver)this).Resolve(catchBlock.ExceptionType, genericArgs);
ProcessMethodDecencies(method, catchBlock, genericArgs);
}
}
else if (node is ILExpression)
{
ILExpression e = node as ILExpression;
foreach (var n in e.Arguments)
{
ProcessMethodDecencies(method, n, genericArgs);
}
if ((e.Code == ILCode.Mkrefany) || (e.Code == ILCode.Refanyval))
{
((IResolver)this).Resolve(ClassNames.SystemTypedReference.ClassName);
}
if (e.Code == ILCode.Refanytype)
{
((IResolver)this).Resolve(ClassNames.SystemTypedReference.ClassName);
((IResolver)this).Resolve(ClassNames.SystemRuntimeTypeHandle.ClassName);
}
if (e.Code == ILCode.Arglist)
{
((IResolver)this).Resolve(ClassNames.SystemRuntimeArgumentHandle.ClassName);
}
if (e.Code.IsExternalRealization())
{
((IResolver)this).Resolve(ClassNames.CIL2JavaVESInstructions.ClassName);
}
if (e.Code == ILCode.Ldc_Decimal)
{
((IResolver)this).Resolve(ClassNames.SystemDecimal.ClassNames);
}
if (e.Code == ILCode.Ldtoken)
{
if (e.Operand is TypeReference)
{
((IResolver)this).Resolve(ClassNames.SystemRuntimeTypeHandle.ClassName);
}
else if (e.Operand is FieldReference)
{
((IResolver)this).Resolve(ClassNames.SystemRuntimeFieldHandle.ClassName);
}
else if (e.Operand is MethodReference)
{
((IResolver)this).Resolve(ClassNames.SystemRuntimeMethodHandle.ClassName);
}
}
if (e.Operand is ILVariable)
{
((IResolver)this).Resolve(((ILVariable)e.Operand).Type, genericArgs);
}
if (e.Operand is TypeReference)
{
((IResolver)this).Resolve((TypeReference)e.Operand, genericArgs);
}
if (e.Operand is MethodReference)
{
((IResolver)this).Resolve((MethodReference)e.Operand, genericArgs);
}
if (e.Operand is FieldReference)
{
InterField fld = ((IResolver)this).Resolve((FieldReference)e.Operand, genericArgs);
bool needAccessor = false;
if ((fld.IsPrivate) && (fld.DeclaringType != method.DeclaringType))
{
needAccessor = true;
}
else if ((fld.IsProtected) && (fld.DeclaringType != method.DeclaringType) &&
(!method.DeclaringType.IsSuper(fld.DeclaringType)))
{
needAccessor = true;
}
if (needAccessor)
{
switch (e.Code)
{
case ILCode.Ldflda:
case ILCode.Ldsflda:
if (fld.FieldType.IsValueType)
{
fld.DeclaringType.AddFieldAccessor(new FieldAccessor(FieldAccessorType.Getter, fld));
}
break;
case ILCode.Ldfld:
case ILCode.Ldsfld:
fld.DeclaringType.AddFieldAccessor(new FieldAccessor(FieldAccessorType.Getter, fld));
break;
case ILCode.Stfld:
case ILCode.Stsfld:
fld.DeclaringType.AddFieldAccessor(new FieldAccessor(FieldAccessorType.Setter, fld));
break;
}
}
}
InterType expected = null;
InterType inferred = null;
if (e.ExpectedType != null)
{
expected = ((IResolver)this).Resolve(e.ExpectedType, genericArgs);
}
if (e.InferredType != null)
{
inferred = ((IResolver)this).Resolve(e.InferredType, genericArgs);
}
if ((expected != null) && (expected.IsInterface) && (inferred != null) && (inferred.IsArray))
{
((IResolver)this).Resolve(ClassNames.ArraysInterfaceAdapterTypeName,
new List <InterGenericArgument>()
{
new InterGenericArgument(GenericArgumentOwnerType.Type, 0, inferred.ElementType)
});
}
}
else if (node is ILWhileLoop)
{
ILWhileLoop loop = node as ILWhileLoop;
ProcessMethodDecencies(method, loop.Condition, genericArgs);
ProcessMethodDecencies(method, loop.BodyBlock, genericArgs);
}
else if (node is ILCondition)
{
ILCondition cond = node as ILCondition;
ProcessMethodDecencies(method, cond.Condition, genericArgs);
ProcessMethodDecencies(method, cond.TrueBlock, genericArgs);
ProcessMethodDecencies(method, cond.FalseBlock, genericArgs);
}
else if (node is ILSwitch)
{
ILSwitch sw = node as ILSwitch;
ProcessMethodDecencies(method, sw.Condition, genericArgs);
foreach (var c in sw.CaseBlocks)
{
ProcessMethodDecencies(method, c, genericArgs);
}
}
else if (node is ILFixedStatement)
{
ILFixedStatement fs = node as ILFixedStatement;
foreach (var n in fs.Initializers)
{
ProcessMethodDecencies(method, n, genericArgs);
}
ProcessMethodDecencies(method, fs.BodyBlock, genericArgs);
}
}
