/// <summary>
///
/// </summary>
internal static void FillInTypes(IMetadataHost host, ControlAndDataFlowGraph <BasicBlock, Instruction> cfg)
{
Contract.Requires(host != null);
Contract.Requires(cfg != null);
var stack = new Stack <Instruction>(cfg.MethodBody.MaxStack, new List <Instruction>(0));
var numberOfBlocks = cfg.BlockFor.Count;
var blocksToVisit = new Queue <BasicBlock>((int)numberOfBlocks);
var blocksAlreadyVisited = new SetOfObjects(numberOfBlocks);
var inferencer = new TypeInferencer <BasicBlock, Instruction>(host, cfg, stack, blocksToVisit, blocksAlreadyVisited);
foreach (var root in cfg.RootBlocks)
{
blocksToVisit.Enqueue(root);
while (blocksToVisit.Count != 0)
{
inferencer.DequeueBlockAndFillInItsTypes();
}
}
//At this point, all reachable code blocks have had their types inferred. Now look for unreachable blocks.
foreach (var block in cfg.AllBlocks)
{
if (blocksAlreadyVisited.Contains(block))
{
continue;
}
blocksToVisit.Enqueue(block);
while (blocksToVisit.Count != 0)
{
inferencer.DequeueBlockAndFillInItsTypes();
}
}
}
private void DequeueBlockAndFillInItsTypes()
{
var block = this.blocksToVisit.Dequeue();
Contract.Assume(block != null); //this.blocksToVisit only has non null elements, but we can't put that in a contract that satisfies the checker
if (!this.blocksAlreadyVisited.Add(block))
{
return; //The same block can be added multiple times to the queue.
}
//The block either has no operand stack setup instructions, or we presume that a predecessor block has already assigned types to them.
foreach (var stackSetupInstruction in block.OperandStack)
{
Contract.Assume(stackSetupInstruction != null); //block.OperandStack only has non null elements, but we can't put that in a contract that satisfies the checker
this.stack.Push(stackSetupInstruction);
}
foreach (var instruction in block.Instructions)
{
Contract.Assume(instruction != null); //block.Instructions only has non null elements, but we can't put that in a contract that satisfies the checker
this.InferTypeAndUpdateStack(instruction);
}
foreach (var successor in this.cfg.SuccessorsFor(block))
{
Contract.Assume(successor != null); //block.Successors only has non null elements, but we can't put that in a contract that satisfies the checker
this.TransferTypesFromStackTo(successor);
if (blocksAlreadyVisited.Contains(successor))
{
continue;
}
blocksToVisit.Enqueue(successor); //The block might already be in the queue, but we can deal with this more efficiently by checking blocksAlreadyVisited when dequeueing.
}
this.stack.Clear();
}
private void AddEdgesForSwitch(IOperation ilOperation, BasicBlock currentBlock, List <BasicBlock> edges, Instruction instruction)
{
Contract.Requires(ilOperation != null);
Contract.Requires(currentBlock != null);
Contract.Requires(ilOperation.OperationCode == OperationCode.Switch);
Contract.Requires(edges != null);
Contract.Requires(instruction != null);
Contract.Assume(ilOperation.Value is uint[]); //This is an informally specified property of the Metadata model.
uint[] branches = (uint[])ilOperation.Value;
SetOfObjects currentSuccesors = new SetOfObjects((uint)branches.Length);
foreach (uint targetAddress in branches)
{
this.blocksThatTarget.Add(targetAddress, currentBlock);
var target = this.cdfg.BlockFor[targetAddress];
Contract.Assume(target != null); //All branch targets must have blocks, but we can't put that in a contract that satisfies the checker.
if (currentSuccesors.Contains(target))
{
continue;
}
currentSuccesors.Add(target);
edges.Add(target);
}
}
private void SetupTraversalOrders()
{
Contract.Ensures(this.postOrder != null);
Contract.Ensures(this.preOrder != null);
var n = cfg.AllBlocks.Count;
this.postOrder = new BasicBlock[n];
this.preOrder = new BasicBlock[n];
uint preorderCounter = 0;
uint postorderCounter = 0;
var alreadyTraversed = new SetOfObjects((uint)n);
foreach (var rootBlock in cfg.RootBlocks)
{
Contract.Assume(rootBlock != null);
this.SetupTraversalOrders(rootBlock, alreadyTraversed, ref preorderCounter, ref postorderCounter);
}
Contract.Assume(preorderCounter == postorderCounter);
if (preorderCounter != n)
{
//Add unreachable blocks to traversal order, treating them as if they were roots.
foreach (var block in cfg.AllBlocks)
{
Contract.Assume(block != null);
if (alreadyTraversed.Contains(block))
{
continue;
}
this.SetupTraversalOrders(block, alreadyTraversed, ref preorderCounter, ref postorderCounter);
}
}
Contract.Assume(this.postOrder != null);
Contract.Assume(this.preOrder != null);
}
private void DequeueBlockAndSetupDataFlow()
{
var block = this.blocksToVisit.Dequeue();
Contract.Assume(block != null); //this.blocksToVisit only has non null elements, but we can't put that in a contract that satisfies the checker
if (!this.blocksAlreadyVisited.Add(block))
{
return; //The same block can be added multiple times to the queue.
}
foreach (var instruction in block.OperandStack)
{
Contract.Assume(instruction != null); //block.OperandStack only has non null elements, but we can't put that in a contract that satisfies the checker
this.stack.Push(instruction);
}
foreach (var instruction in block.Instructions)
{
Contract.Assume(instruction != null); //block.Instructions only has non null elements, but we can't put that in a contract that satisfies the checker
this.SetupDataFlowFor(instruction);
}
foreach (var successor in this.cdfg.SuccessorsFor(block))
{
Contract.Assume(successor != null); //block.Successors only has non null elements, but we can't put that in a contract that satisfies the checker
this.SetupStackFor(successor);
if (blocksAlreadyVisited.Contains(successor))
{
continue;
}
blocksToVisit.Enqueue(successor); //The block might already be in the queue, but we can deal with this more efficiently by checking blocksAlreadyVisited when dequeueing.
}
this.stack.Clear();
}
private void AddTransferInstructions(BasicBlock block, BasicBlock succ, int successorIndex, SetOfObjects definedSSAVariables)
{
Contract.Requires(block != null);
Contract.Requires(succ != null);
Contract.Requires(definedSSAVariables != null);
if (succ.Joins == null)
{
return;
}
foreach (var join in succ.Joins)
{
Contract.Assume(join.Join1 != null);
if (definedSSAVariables.Contains(join.Join1))
{
this.AddTransferInstruction(block, succ, successorIndex, join.NewLocal, join.Join1, join.Type);
continue;
}
if (join.Join2 == null)
{
continue;
}
if (definedSSAVariables.Contains(join.Join2))
{
this.AddTransferInstruction(block, succ, successorIndex, join.NewLocal, join.Join2, join.Type);
continue;
}
if (join.OtherJoins == null)
{
continue;
}
foreach (var joini in join.OtherJoins)
{
if (!definedSSAVariables.Contains(joini))
{
continue;
}
this.AddTransferInstruction(block, succ, successorIndex, join.NewLocal, joini, join.Type);
}
}
}
private bool NextReferenceIsAssignment(ILocalDefinition local, BasicBlock<Instruction> bb, int offset, SetOfObjects blocksAlreadyVisited) {
Contract.Requires(bb != null);
Contract.Requires(offset >= 0);
Contract.Requires(blocksAlreadyVisited != null);
blocksAlreadyVisited.Add(bb);
for (int i = offset, n = bb.Instructions.Count; i < n; i++) {
var instruction = bb.Instructions[i];
switch (instruction.Operation.OperationCode) {
case OperationCode.Ldloc:
case OperationCode.Ldloc_0:
case OperationCode.Ldloc_1:
case OperationCode.Ldloc_2:
case OperationCode.Ldloc_3:
case OperationCode.Ldloc_S:
case OperationCode.Ldloca:
case OperationCode.Ldloca_S:
if (instruction.Operation.Value == local) return false;
break;
case OperationCode.Stloc:
case OperationCode.Stloc_0:
case OperationCode.Stloc_1:
case OperationCode.Stloc_2:
case OperationCode.Stloc_3:
case OperationCode.Stloc_S:
if (instruction.Operation.Value == local) return true;
break;
}
}
var result = true;
foreach (var successor in this.cdfg.SuccessorsFor(bb)) {
Contract.Assume(successor != null);
if (blocksAlreadyVisited.Contains(successor)) continue;
result &= this.NextReferenceIsAssignment(local, successor, 0, blocksAlreadyVisited);
if (!result) break;
}
return result;
}
/// <summary>
/// Provides the host with an opportunity to add, remove or substitute assembly references in the given list.
/// This avoids the cost of rewriting the entire unit in order to make such changes.
/// </summary>
/// <param name="referringUnit">The unit that contains these references.</param>
/// <param name="assemblyReferences">The assembly references to substitute.</param>
/// <returns>Usually assemblyReferences, but occasionally a modified enumeration.</returns>
public override IEnumerable<IAssemblyReference> Redirect(IUnit referringUnit, IEnumerable<IAssemblyReference> assemblyReferences) {
if (!this.projectToCLRTypes) return assemblyReferences;
var referringModule = referringUnit as IModule;
if (referringModule == null || referringModule.ContainingAssembly == null || !(referringModule.ContainingAssembly.ContainsForeignTypes)) return assemblyReferences;
var platformType = (WindowsRuntimePlatform)this.PlatformType;
var standardRefs = new SetOfObjects();
if (string.Equals(this.CoreAssemblySymbolicIdentity.Name.Value, "System.Runtime", StringComparison.OrdinalIgnoreCase)) {
standardRefs.Add(platformType.SystemObjectModel.AssemblyIdentity);
} else {
standardRefs.Add(platformType.System.AssemblyIdentity);
}
standardRefs.Add(platformType.CoreAssemblyRef.AssemblyIdentity);
standardRefs.Add(platformType.SystemRuntimeWindowsRuntime.AssemblyIdentity);
standardRefs.Add(platformType.SystemRuntimeWindowsRuntimeUIXaml.AssemblyIdentity);
var result = new List<IAssemblyReference>();
foreach (var aref in assemblyReferences) {
if (string.Equals(aref.Name.Value, "mscorlib", StringComparison.OrdinalIgnoreCase)) continue;
result.Add(aref);
standardRefs.Remove(aref.AssemblyIdentity);
}
if (standardRefs.Contains(platformType.CoreAssemblyRef.AssemblyIdentity)) result.Add(platformType.CoreAssemblyRef);
if (standardRefs.Contains(platformType.SystemRuntimeInteropServicesWindowsRuntime.AssemblyIdentity)) result.Add(platformType.SystemRuntimeInteropServicesWindowsRuntime);
if (standardRefs.Contains(platformType.SystemRuntimeWindowsRuntime.AssemblyIdentity)) result.Add(platformType.SystemRuntimeWindowsRuntime);
if (standardRefs.Contains(platformType.SystemRuntimeWindowsRuntimeUIXaml.AssemblyIdentity)) result.Add(platformType.SystemRuntimeWindowsRuntimeUIXaml);
if (standardRefs.Contains(platformType.SystemObjectModel.AssemblyIdentity)) result.Add(platformType.SystemObjectModel);
if (standardRefs.Contains(platformType.System.AssemblyIdentity)) result.Add(platformType.System);
return IteratorHelper.GetReadonly(result.ToArray());
}
