private ExceptionHandler BeginHandler(HandlerKind kind)
//^ requires InTryBody;
{
ILGeneratorLabel handlerStart = new ILGeneratorLabel(false);
this.MarkLabel(handlerStart);
TryBody currentTryBody = this.tryBodyStack.Peek();
ExceptionHandler handler = new ExceptionHandler(kind, currentTryBody, handlerStart);
if (currentTryBody.end == null)
{
currentTryBody.end = handlerStart;
}
else if (this.handlers.Count > 0)
{
for (int i = this.handlers.Count - 1; i >= 0; i--)
{
if (this.handlers[i].HandlerEnd == null)
{
this.handlers[i].HandlerEnd = handlerStart;
break;
}
}
}
this.handlers.Add(handler);
return(handler);
}
internal ExceptionHandler(HandlerKind kind, TryBody tryBlock, ILGeneratorLabel handlerStart)
{
this.ExceptionType = Dummy.TypeReference;
this.kind = kind;
this.HandlerStart = handlerStart;
this.tryBlock = tryBlock;
}
/// <summary>
/// Begins the body of a try statement.
/// </summary>
public void BeginTryBody()
//^ ensures InTryBody;
{
ILGeneratorLabel tryBodyStart = new ILGeneratorLabel(false);
this.MarkLabel(tryBodyStart);
this.tryBodyStack.Push(new TryBody(tryBodyStart));
}
/// <summary>
/// Begins the part of a filter handler that is invoked on the second pass if the filter condition returns true on the first pass.
/// </summary>
public void BeginFilterBody()
{
this.Emit(OperationCode.Endfilter);
ILGeneratorLabel handlerStart = new ILGeneratorLabel(false);
this.MarkLabel(handlerStart);
this.handlers[handlers.Count - 1].HandlerStart = handlerStart;
}
/// <summary>
/// Returns a label that represents the given offset in the original IL. This label must be marked
/// at the corresponding location in the rewritten IL.
/// </summary>
protected virtual ILGeneratorLabel GetLabelFor(uint offset)
{
Contract.Ensures(Contract.Result <ILGeneratorLabel>() != null);
var result = this.labelFor[offset];
if (result == null)
{
this.labelFor[offset] = result = new ILGeneratorLabel();
}
return(result);
}
/// <summary>
/// Puts the specified instruction onto the Microsoft intermediate language (MSIL) stream and leaves space to include a label when fixes are done.
/// </summary>
/// <param name="opcode">The Microsoft intermediate language (MSIL) instruction to be put onto the stream.</param>
/// <param name="label">The label to which to branch from this location.</param>
public void Emit(OperationCode opcode, ILGeneratorLabel label)
{
if (opcode == OperationCode.Br && this.operations.Count > 0)
{
Operation previousOp = this.operations[this.operations.Count - 1];
if (previousOp.OperationCode == (OperationCode)int.MaxValue)
{
ILGeneratorLabel labelOfBranch = (ILGeneratorLabel)previousOp.value;
if (labelOfBranch.mayAlias)
{
labelOfBranch.alias = label;
}
}
}
this.operations.Add(new Operation(opcode, this.offset, this.GetCurrentSequencePoint(), label));
this.offset += SizeOfOperationCode(opcode) + SizeOfOffset(opcode);
}
/// <summary>
/// Ends a try body.
/// </summary>
public void EndTryBody()
//^ requires InTryBody;
{
this.tryBodyStack.Pop();
if (this.handlers.Count > 0)
{
ILGeneratorLabel handlerEnd = new ILGeneratorLabel(false);
this.MarkLabel(handlerEnd);
for (int i = this.handlers.Count - 1; i >= 0; i--)
{
if (this.handlers[i].HandlerEnd == null)
{
this.handlers[i].HandlerEnd = handlerEnd;
break;
}
}
}
}
/// <summary>
/// Puts the specified instruction onto the stream of instructions.
/// </summary>
/// <param name="opcode">The Intermediate Language (IL) instruction to be put onto the stream.</param>
public void Emit(OperationCode opcode)
{
if (opcode == OperationCode.Ret)
{
int i = this.operations.Count;
while (--i >= 0)
{
Operation previousOp = this.operations[i];
if (previousOp.OperationCode != (OperationCode)int.MaxValue)
{
break;
}
ILGeneratorLabel labelOfBranch = (ILGeneratorLabel)previousOp.value;
labelOfBranch.labelsReturnInstruction = true;
}
}
this.operations.Add(new Operation(opcode, this.offset, this.GetCurrentSequencePoint(), null));
this.offset += SizeOfOperationCode(opcode);
}
/// <summary>
/// Ends a try body.
/// </summary>
public void EndTryBody()
//^ requires InTryBody;
{
this.tryBodyStack.Pop();
if (this.handlers.Count > 0)
{
ILGeneratorLabel handlerEnd = new ILGeneratorLabel(false);
this.MarkLabel(handlerEnd);
for (int i = this.handlers.Count - 1; i >= 0; i--)
{
var handler = this.handlers[i];
if (handler.HandlerEnd == null)
{
handler.HandlerEnd = handlerEnd;
if (i < this.handlers.Count - 1)
{
this.handlers.RemoveAt(i);
this.handlers.Add(handler);
}
break;
}
}
}
}
/// <summary>
/// Generates IL for the specified conditional.
/// </summary>
/// <param name="conditional">The conditional.</param>
public override void TraverseChildren(IConditional conditional)
{
ILGeneratorLabel falseCase = new ILGeneratorLabel();
ILGeneratorLabel endif = new ILGeneratorLabel();
this.VisitBranchIfFalse(conditional.Condition, falseCase);
this.Traverse(conditional.ResultIfTrue);
this.generator.Emit(OperationCode.Br, endif);
this.generator.MarkLabel(falseCase);
this.StackSize--;
this.Traverse(conditional.ResultIfFalse);
this.generator.MarkLabel(endif);
}
/// <summary>
/// Marks the Microsoft intermediate language (MSIL) stream's current position with the given label.
/// </summary>
public void MarkLabel(ILGeneratorLabel label)
{
label.Offset = this.offset;
this.operations.Add(new Operation((OperationCode)int.MaxValue, this.offset, Dummy.Location, label));
}
public void Compile(string fileName)
{
string appName = Path.GetFileNameWithoutExtension(fileName);
string exeName = appName + ".exe";
string src = "";
using (TextReader file = new StreamReader(fileName))
{
src = file.ReadToEnd();
}
var nameTable = new NameTable();
using (var host = new PeReader.DefaultHost(nameTable))
{
// Load Mirage types
IModule module = host.LoadUnitFrom("Mirage.dll") as IModule;
if (module == null || module is Dummy)
{
return;
}
var machineType = module.GetAllTypes().First(x => x.Name.Value == "Machine");
var inputType = module.GetAllTypes().First(x => x.Name.Value == "ConsoleInput");
var outputType = module.GetAllTypes().First(x => x.Name.Value == "ConsoleOutput");
// Create assembly
var coreAssembly = host.LoadAssembly(host.CoreAssemblySymbolicIdentity);
var assembly = new Assembly()
{
Name = nameTable.GetNameFor(appName),
ModuleName = nameTable.GetNameFor(exeName),
PlatformType = host.PlatformType,
Kind = ModuleKind.ConsoleApplication,
RequiresStartupStub = host.PointerSize == 4,
TargetRuntimeVersion = coreAssembly.TargetRuntimeVersion,
};
assembly.AssemblyReferences.Add(coreAssembly);
// Create namespace
var rootUnitNamespace = new RootUnitNamespace();
assembly.UnitNamespaceRoot = rootUnitNamespace;
rootUnitNamespace.Unit = assembly;
// Create module class
var moduleClass = new NamespaceTypeDefinition()
{
ContainingUnitNamespace = rootUnitNamespace,
InternFactory = host.InternFactory,
IsClass = true,
Name = nameTable.GetNameFor("<Module>"),
};
assembly.AllTypes.Add(moduleClass);
// Create program class
var programClass = new NamespaceTypeDefinition()
{
ContainingUnitNamespace = rootUnitNamespace,
InternFactory = host.InternFactory,
IsClass = true,
IsPublic = true,
Methods = new List<IMethodDefinition>(1),
Name = nameTable.GetNameFor("Program"),
};
programClass.BaseClasses = new List<ITypeReference>() { host.PlatformType.SystemObject };
rootUnitNamespace.Members.Add(programClass);
// Add types to the assembly
assembly.AllTypes.Add(machineType);
foreach (var t in machineType.NestedTypes)
{
assembly.AllTypes.Add(t);
}
assembly.AllTypes.Add(inputType);
assembly.AllTypes.Add(outputType);
assembly.AllTypes.Add(programClass);
// Create main method
var mainMethod = new MethodDefinition()
{
ContainingTypeDefinition = programClass,
InternFactory = host.InternFactory,
IsCil = true,
IsStatic = true,
Name = nameTable.GetNameFor("Main"),
Type = host.PlatformType.SystemVoid,
Visibility = TypeMemberVisibility.Public,
};
assembly.EntryPoint = mainMethod;
programClass.Methods.Add(mainMethod);
// Create constructors and methods
IMethodReference machineConstructor = new Microsoft.Cci.MethodReference(
host,
machineType,
CallingConvention.HasThis,
host.PlatformType.SystemVoid,
host.NameTable.Ctor,
0
);
IMethodReference inputConstructor = new Microsoft.Cci.MethodReference(
host,
inputType,
CallingConvention.HasThis,
host.PlatformType.SystemVoid,
host.NameTable.Ctor,
0
);
var inputCast = TypeHelper.GetMethod(inputType, nameTable.GetNameFor("op_Implicit"), inputType);
IMethodReference outputConstructor = new Microsoft.Cci.MethodReference(
host,
outputType,
CallingConvention.HasThis,
host.PlatformType.SystemVoid,
host.NameTable.Ctor,
0
);
var outputCast = TypeHelper.GetMethod(outputType, nameTable.GetNameFor("op_Implicit"), outputType);
var opIncPointers = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("IncPointers"));
var opDecPointers = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("DecPointers"));
var opIncHiPointer = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("IncHiPointer"));
var opDecHiPointer = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("DecHiPointer"));
var opReflectHiPointer = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("ReflectHiPointer"));
var opLoadHiPointer = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("LoadHiPointer"));
var opDragLoPointer = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("DragLoPointer"));
var opXchPointers = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("XchPointers"));
var opClear = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Clear"));
var opAdd = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Add"));
var opDec = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Dec"));
var opNot = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Not"));
var opAnd = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("And"));
var opOr = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Or"));
var opXor = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Xor"));
var opSal = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Sal"));
var opSar = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Sar"));
var opLoadData = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("LoadData"), host.PlatformType.SystemString);
var opInput = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Input"), inputCast.Type);
var opOutput = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Output"), outputCast.Type);
var opJz = TypeHelper.GetMethod(machineType, nameTable.GetNameFor("Jz"));
// Create program code
var labels = new Stack<ILGeneratorLabel>(100);
var ilGenerator = new ILGenerator(host, mainMethod);
ilGenerator.Emit(OperationCode.Newobj, machineConstructor);
ilGenerator.Emit(OperationCode.Stloc_0);
ilGenerator.Emit(OperationCode.Newobj, inputConstructor);
ilGenerator.Emit(OperationCode.Stloc_1);
ilGenerator.Emit(OperationCode.Newobj, outputConstructor);
ilGenerator.Emit(OperationCode.Stloc_2);
int pc = 0;
while (pc < src.Length)
{
char opcode = src[pc++];
switch (opcode)
{
case '>':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opIncPointers);
break;
case '<':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opDecPointers);
break;
case ']':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opIncHiPointer);
break;
case '[':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opDecHiPointer);
break;
case '#':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opReflectHiPointer);
break;
case '$':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opLoadHiPointer);
break;
case '=':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opDragLoPointer);
break;
case '%':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opXchPointers);
break;
case '_':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opClear);
break;
case '+':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opAdd);
break;
case '-':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opDec);
break;
case '~':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opNot);
break;
case '&':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opAnd);
break;
case '|':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opOr);
break;
case '^':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opXor);
break;
case '*':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opSal);
break;
case '/':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opSar);
break;
case '(':
int dataStart = pc;
int dataEnd = dataStart;
while (src[pc++] != ')')
{
dataEnd = pc;
}
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Ldstr, src.Substring(dataStart, dataEnd - dataStart));
ilGenerator.Emit(OperationCode.Callvirt, opLoadData);
break;
case '?':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Ldloc_1);
ilGenerator.Emit(OperationCode.Call, inputCast);
ilGenerator.Emit(OperationCode.Callvirt, opInput);
break;
case '!':
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Ldloc_2);
ilGenerator.Emit(OperationCode.Call, outputCast);
ilGenerator.Emit(OperationCode.Callvirt, opOutput);
break;
case '{':
var cycleStart = new ILGeneratorLabel();
var cycleEnd = new ILGeneratorLabel();
labels.Push(cycleStart);
labels.Push(cycleEnd);
ilGenerator.Emit(OperationCode.Br, cycleEnd);
ilGenerator.MarkLabel(cycleStart);
break;
case '}':
ilGenerator.MarkLabel(labels.Pop());
ilGenerator.Emit(OperationCode.Ldloc_0);
ilGenerator.Emit(OperationCode.Callvirt, opJz);
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Stloc_3);
ilGenerator.Emit(OperationCode.Ldloc_3);
ilGenerator.Emit(OperationCode.Brtrue, labels.Pop());
break;
default:
break;
}
}
ilGenerator.Emit(OperationCode.Ret);
mainMethod.Body = new ILGeneratorMethodBody(
ilGenerator,
true,
8,
mainMethod,
new List<ILocalDefinition>() {
new LocalDefinition() { Type = machineType },
new LocalDefinition() { Type = inputType },
new LocalDefinition() { Type = outputType },
new LocalDefinition() { Type = host.PlatformType.SystemInt32 },
},
Enumerable<ITypeDefinition>.Empty
);
using (var peStream = File.Create(exeName))
{
PeWriter.WritePeToStream(assembly, host, peStream);
}
}
}
/// <summary>
/// Begins the part of a filter handler that is invoked on the second pass if the filter condition returns true on the first pass.
/// </summary>
public void BeginFilterBody()
{
this.Emit(OperationCode.Endfilter);
ILGeneratorLabel handlerStart = new ILGeneratorLabel(false);
this.MarkLabel(handlerStart);
this.handlers[handlers.Count-1].HandlerStart = handlerStart;
}
/// <summary>
/// Puts the specified instruction onto the Microsoft intermediate language (MSIL) stream and leaves space to include a label when fixes are done.
/// </summary>
/// <param name="opcode">The Microsoft intermediate language (MSIL) instruction to be put onto the stream.</param>
/// <param name="label">The label to which to branch from this location.</param>
public void Emit(OperationCode opcode, ILGeneratorLabel label)
{
if (opcode == OperationCode.Br && this.operations.Count > 0) {
Operation previousOp = this.operations[this.operations.Count-1];
if (previousOp.OperationCode == (OperationCode)int.MaxValue) {
ILGeneratorLabel labelOfBranch = (ILGeneratorLabel)previousOp.value;
if (labelOfBranch.mayAlias) labelOfBranch.alias = label;
}
}
this.operations.Add(new Operation(opcode, this.offset, this.GetCurrentSequencePoint(), label));
this.offset += SizeOfOperationCode(opcode)+SizeOfOffset(opcode);
}
private ILGeneratorLabel GetLabelFor(uint offset) {
var result = this.labelFor[offset];
if (result == null)
this.labelFor[offset] = result = new ILGeneratorLabel();
return result;
}
internal ExceptionHandler(HandlerKind kind, TryBody tryBlock, ILGeneratorLabel handlerStart)
{
this.ExceptionType = Dummy.TypeReference;
this.kind = kind;
this.HandlerStart = handlerStart;
this.tryBlock = tryBlock;
}
private void GenerateDownLevelLockStatement(ILockStatement lockStatement)
{
var systemThreading = new NestedUnitNamespaceReference(this.host.PlatformType.SystemObject.ContainingUnitNamespace,
this.host.NameTable.GetNameFor("Threading"));
var systemThreadingMonitor = new NamespaceTypeReference(this.host, systemThreading, this.host.NameTable.GetNameFor("Monitor"), 0,
isEnum: false, isValueType: false, typeCode: PrimitiveTypeCode.NotPrimitive);
var parameters = new IParameterTypeInformation[2];
var monitorEnter = new MethodReference(this.host, systemThreadingMonitor, CallingConvention.Default, this.host.PlatformType.SystemVoid,
this.host.NameTable.GetNameFor("Enter"), 0, this.host.PlatformType.SystemObject);
var monitorExit = new MethodReference(this.host, systemThreadingMonitor, CallingConvention.Default, this.host.PlatformType.SystemVoid,
this.host.NameTable.GetNameFor("Exit"), 0, this.host.PlatformType.SystemObject);
this.EmitSequencePoint(lockStatement.Locations);
var guardObject = new TemporaryVariable(lockStatement.Guard.Type, this.method);
this.Traverse(lockStatement.Guard);
this.generator.Emit(OperationCode.Dup); this.StackSize++;
this.VisitAssignmentTo(guardObject);
this.generator.Emit(OperationCode.Call, monitorEnter);
this.StackSize--;
//try
var savedCurrentTryCatch = this.currentTryCatch;
this.currentTryCatch = lockStatement;
var savedCurrentTryCatchFinallyEnd = this.currentTryCatchFinallyEnd;
this.currentTryCatchFinallyEnd = new ILGeneratorLabel();
this.generator.BeginTryBody();
this.Traverse(lockStatement.Body);
if (!this.lastStatementWasUnconditionalTransfer)
this.generator.Emit(OperationCode.Leave, this.currentTryCatchFinallyEnd);
//finally
this.generator.BeginFinallyBlock();
//if (status)
this.LoadLocal(guardObject);
this.generator.Emit(OperationCode.Call, monitorExit);
this.StackSize--;
//monitor exit
this.generator.Emit(OperationCode.Endfinally);
this.generator.EndTryBody();
this.generator.MarkLabel(this.currentTryCatchFinallyEnd);
this.currentTryCatchFinallyEnd = savedCurrentTryCatchFinallyEnd;
this.currentTryCatch = savedCurrentTryCatch;
this.lastStatementWasUnconditionalTransfer = false;
}
internal bool LabelIsOutsideCurrentExceptionBlock(ILGeneratorLabel label)
{
IStatement tryCatchContainingTarget = null;
this.mostNestedTryCatchFor.TryGetValue(label, out tryCatchContainingTarget);
return this.currentTryCatch != tryCatchContainingTarget;
}
// creates a method for a given method CFG (IMPORTANT: it updates the operations
// and exception handlers of the existing method, does not create a new method)
public void createMethodFromCfg(MethodCfg methodCfg) {
// list of basic blocks that belong together logically (i.e. BB2 lies directly behind BB1 because it reaches it without a branch)
IList<BasicBlockUnion> basicBlockUnions = new List<BasicBlockUnion>();
// first step: create basic block unions
// create first basic block union starting from the start basic block
BasicBlockUnion firstBasicBlockUnion = new BasicBlockUnion();
this.createRecursivelyBasicBlockUnion(basicBlockUnions, firstBasicBlockUnion, methodCfg.startBasicBlock);
basicBlockUnions.Add(firstBasicBlockUnion);
// create basic block unions for the rest of the basic blocks
foreach (BasicBlock tempBB in methodCfg.basicBlocks) {
// create a basic block union (if basic block is not contained by another existing basic block union)
BasicBlockUnion basicBlockUnion = new BasicBlockUnion();
this.createRecursivelyBasicBlockUnion(basicBlockUnions, basicBlockUnion, tempBB);
// if the newly created basic block union contains basic blocks
// => add to list of basic block unions
if (basicBlockUnion.basicBlocks.Count() != 0) {
basicBlockUnions.Add(basicBlockUnion);
}
}
// step two: merge basic block unions with respect to the exception handler
foreach (OperationExceptionInformation exceptionHandler in methodCfg.method.Body.OperationExceptionInformation) {
// create a temporary object to reorder the basic block unions with respect to the exception handler
BasicBlockUnionExceptionHandlerOrder tempNewOrder = new BasicBlockUnionExceptionHandlerOrder();
tempNewOrder.exceptionHandler = exceptionHandler;
// find all basic blocks that are connected to the current exception handler
foreach (BasicBlockUnion basicBlockUnion in basicBlockUnions) {
foreach (BasicBlock basicBlock in basicBlockUnion.basicBlocks) {
// ignore all basic blocks that do not have any try/catch/finally handler in it
if (basicBlock.tryBlocks.Count() == 0 && basicBlock.handlerBlocks.Count() == 0) {
continue;
}
// find the try block that is connected to the current exception handler
foreach (TryBlock tryBlock in basicBlock.tryBlocks) {
// ignore try blocks that do not belong to the current exception handler
if (tryBlock.exceptionHandler != exceptionHandler) {
continue;
}
// check if basic block union already resides in try body
// if not => add to try body
if (!tempNewOrder.tryBody.Contains(basicBlockUnion)) {
tempNewOrder.tryBody.Add(basicBlockUnion);
}
// check if the basic block starts the try block
if (tryBlock.firstBasicBlockOfTryBlock) {
tempNewOrder.tryStart = basicBlockUnion;
}
// check if the basic block ends the try block
if (tryBlock.lastBasicBlockOfTryBlock) {
tempNewOrder.tryEnd = basicBlockUnion;
}
}
// find the handler block that is connected to the current exception handler
foreach (HandlerBlock handlerBlock in basicBlock.handlerBlocks) {
// ignore handler blocks that do not belong to the current exception handler
if (handlerBlock.exceptionHandler != exceptionHandler) {
continue;
}
// check if basic block union already resides in handler body
// if not => add to handler body
if (!tempNewOrder.handlerBody.Contains(basicBlockUnion)) {
tempNewOrder.handlerBody.Add(basicBlockUnion);
}
// check if the basic block starts the handler block
if (handlerBlock.firstBasicBlockOfHandlerBlock) {
tempNewOrder.handlerStart = basicBlockUnion;
}
// check if the basic block ends the handler block
if (handlerBlock.lastBasicBlockOfHandlerBlock) {
tempNewOrder.handlerEnd = basicBlockUnion;
}
}
}
}
if (tempNewOrder.tryStart == null
|| tempNewOrder.tryEnd == null
|| tempNewOrder.handlerStart == null
|| tempNewOrder.handlerEnd == null) {
throw new ArgumentException("Could not find all try/catch beginnings/ends.");
}
// merge basic block unions with respect to the current exception handler
// check if the complete exception handling is done in only one basic block union
// => ignore it
if (tempNewOrder.tryStart == tempNewOrder.tryEnd
&& tempNewOrder.handlerStart == tempNewOrder.handlerEnd
&& tempNewOrder.tryStart == tempNewOrder.handlerStart) {
continue;
}
// if not everything lies in the same basic block union
// extend the basic block union that starts the try block
BasicBlockUnion extendedUnion = tempNewOrder.tryStart;
// if try block start and end are the same => nothing to merge
// else merge the basic block unions
if (tempNewOrder.tryStart != tempNewOrder.tryEnd) {
foreach (BasicBlockUnion tryBodyBasicBlockUnion in tempNewOrder.tryBody) {
// ignore the basic block union that starts the try block (already in extended union)
// and ignore the basic block union that ends the try block (is added last)
if (tryBodyBasicBlockUnion == tempNewOrder.tryStart
|| tryBodyBasicBlockUnion == tempNewOrder.tryEnd) {
continue;
}
// extend first basic block union with the basic block union of the
// try block body and remove the added one from the list of basic block unions
extendedUnion.basicBlocks.AddRange(tryBodyBasicBlockUnion.basicBlocks);
basicBlockUnions.Remove(tryBodyBasicBlockUnion);
}
// extend first basic block union with the basic block union of the
// try block end and remove the added one from the list of basic block unions
extendedUnion.basicBlocks.AddRange(tempNewOrder.tryEnd.basicBlocks);
basicBlockUnions.Remove(tempNewOrder.tryEnd);
}
// if the try block end and the handler block start are not the same basic block union
// => merge the union of the handler block start to the current basic block union
if (tempNewOrder.tryEnd != tempNewOrder.handlerStart) {
extendedUnion.basicBlocks.AddRange(tempNewOrder.handlerStart.basicBlocks);
basicBlockUnions.Remove(tempNewOrder.handlerStart);
}
// if handler block start and end are the same => nothing to merge
// else merge the basic block unions
if (tempNewOrder.handlerStart != tempNewOrder.handlerEnd) {
foreach (BasicBlockUnion handlerBodyBasicBlockUnion in tempNewOrder.handlerBody) {
// ignore the basic block union that starts the handler block (already in extended union)
// and ignore the basic block union that ends the handler block (is added last)
if (handlerBodyBasicBlockUnion == tempNewOrder.handlerStart
|| handlerBodyBasicBlockUnion == tempNewOrder.handlerEnd) {
continue;
}
// add basic block union of the handler block body to the extended basic block union
// and remove the added one from the list of basic block unions
extendedUnion.basicBlocks.AddRange(handlerBodyBasicBlockUnion.basicBlocks);
basicBlockUnions.Remove(handlerBodyBasicBlockUnion);
}
// extend the extended basic block union with the basic block union of the
// handler block end and remove the added one from the list of basic block unions
extendedUnion.basicBlocks.AddRange(tempNewOrder.handlerEnd.basicBlocks);
basicBlockUnions.Remove(tempNewOrder.handlerEnd);
}
}
// step three: create one list of operations and modify jump offsets
// create a list of operations from the basic blocks,
// update basic block start/end indices accordingly
// and update the offsets of the operations (needed to update branch operations)
IList<IOperation> methodOperations = new List<IOperation>();
int operationIdx = 0;
uint currentOffset = 0;
foreach (BasicBlockUnion basicBlockUnion in basicBlockUnions) {
foreach (BasicBlock basicBlock in basicBlockUnion.basicBlocks) {
basicBlock.startIdx = operationIdx;
//foreach (IOperation operation in basicBlock.operations) {
for (int opIdx = 0; opIdx < basicBlock.operations.Count(); opIdx++) {
IOperation operation = basicBlock.operations.ElementAt(opIdx);
// a new operation object is needed because the old operations
// are read only due to cci
InternalOperation newOperation = new InternalOperation();
// exchange every short instruction with its larger one
switch (operation.OperationCode) {
case OperationCode.Beq_S:
newOperation.OperationCode = OperationCode.Beq;
break;
case OperationCode.Bge_S:
newOperation.OperationCode = OperationCode.Bge;
break;
case OperationCode.Bge_Un_S:
newOperation.OperationCode = OperationCode.Bge_Un;
break;
case OperationCode.Bgt_S:
newOperation.OperationCode = OperationCode.Bgt;
break;
case OperationCode.Bgt_Un_S:
newOperation.OperationCode = OperationCode.Bgt_Un;
break;
case OperationCode.Ble_S:
newOperation.OperationCode = OperationCode.Ble;
break;
case OperationCode.Ble_Un_S:
newOperation.OperationCode = OperationCode.Ble_Un;
break;
case OperationCode.Blt_S:
newOperation.OperationCode = OperationCode.Blt;
break;
case OperationCode.Blt_Un_S:
newOperation.OperationCode = OperationCode.Blt_Un;
break;
case OperationCode.Bne_Un_S:
newOperation.OperationCode = OperationCode.Bne_Un;
break;
case OperationCode.Br_S:
newOperation.OperationCode = OperationCode.Br;
break;
case OperationCode.Brfalse_S:
newOperation.OperationCode = OperationCode.Brfalse;
break;
case OperationCode.Brtrue_S:
newOperation.OperationCode = OperationCode.Brtrue;
break;
case OperationCode.Ldarg_S:
newOperation.OperationCode = OperationCode.Ldarg;
break;
case OperationCode.Ldarga_S:
newOperation.OperationCode = OperationCode.Ldarga;
break;
case OperationCode.Ldc_I4_S:
newOperation.OperationCode = OperationCode.Ldc_I4;
break;
case OperationCode.Ldloc_S:
newOperation.OperationCode = OperationCode.Ldloc;
break;
case OperationCode.Ldloca_S:
newOperation.OperationCode = OperationCode.Ldloca;
break;
case OperationCode.Leave_S:
newOperation.OperationCode = OperationCode.Leave;
break;
case OperationCode.Starg_S:
newOperation.OperationCode = OperationCode.Starg;
break;
case OperationCode.Stloc_S:
newOperation.OperationCode = OperationCode.Stloc;
break;
default:
newOperation.OperationCode = operation.OperationCode;
break;
}
newOperation.Value = operation.Value;
newOperation.Location = operation.Location;
newOperation.Offset = currentOffset;
methodOperations.Add(newOperation);
// replace old operation in basic block with newly created one
basicBlock.operations[opIdx] = newOperation;
operationIdx++;
currentOffset += CfgBuilder.getSizeOfOperation(newOperation);
}
basicBlock.endIdx = operationIdx - 1;
}
}
// step four: update branches with new target offsets
foreach (BasicBlock tempBB in methodCfg.basicBlocks) {
InternalOperation branchOperation = (InternalOperation)methodOperations.ElementAt(tempBB.endIdx);
// check which kind of exit branch is used by this basic block and update its operation accordingly
if (tempBB.exitBranch as NoBranchTarget != null) {
continue;
}
else if (tempBB.exitBranch as TryBlockTarget != null) {
continue;
}
else if (tempBB.exitBranch as ConditionalBranchTarget != null) {
ConditionalBranchTarget tempExitBranch = (tempBB.exitBranch as ConditionalBranchTarget);
// check if the branch is done by a branch operation
if (!CfgBuilder.isBranchOperation(branchOperation)) {
throw new ArgumentException("Branch is not done by a valid branch operation.");
}
// get index of the branch target
int targetBranchIdx = tempExitBranch.takenTarget.startIdx;
// update offset of the taken branch
branchOperation.Value = methodOperations.ElementAt(targetBranchIdx).Offset;
}
else if (tempBB.exitBranch as SwitchBranchTarget != null) {
SwitchBranchTarget tempExitBranch = (tempBB.exitBranch as SwitchBranchTarget);
// check if the branch is done by a branch operation
if (!CfgBuilder.isBranchOperation(branchOperation)) {
throw new ArgumentException("Branch is not done by a valid branch operation.");
}
// update all switch branches
for (int switchIdx = 0; switchIdx < tempExitBranch.takenTarget.Count(); switchIdx++) {
// get index of the branch target
int targetBranchIdx = tempExitBranch.takenTarget.ElementAt(switchIdx).startIdx;
// update offset of the taken branch
((uint[])branchOperation.Value)[switchIdx] = methodOperations.ElementAt(targetBranchIdx).Offset;
}
}
else if (tempBB.exitBranch as UnconditionalBranchTarget != null) {
UnconditionalBranchTarget tempExitBranch = (tempBB.exitBranch as UnconditionalBranchTarget);
// check if the branch is done by a branch operation
if (!CfgBuilder.isBranchOperation(branchOperation)) {
throw new ArgumentException("Branch is not done by a valid branch operation.");
}
// get index of the branch target
int targetBranchIdx = tempExitBranch.takenTarget.startIdx;
// update offset of the taken branch
branchOperation.Value = methodOperations.ElementAt(targetBranchIdx).Offset;
}
else if (tempBB.exitBranch as ExitBranchTarget != null) {
continue;
}
else if (tempBB.exitBranch as ThrowBranchTarget != null) {
continue;
}
else if (tempBB.exitBranch as ExceptionBranchTarget != null) {
ExceptionBranchTarget tempExitBranch = (tempBB.exitBranch as ExceptionBranchTarget);
// check if the branch is done by a branch operation
if (!CfgBuilder.isBranchOperation(branchOperation)) {
throw new ArgumentException("Branch is not done by a valid branch operation.");
}
// get index of the branch target
int targetBranchIdx = tempExitBranch.exitTarget.startIdx;
// update offset of the taken branch
branchOperation.Value = methodOperations.ElementAt(targetBranchIdx).Offset;
}
else {
throw new ArgumentException("Do not know how to handle exit branch.");
}
}
// step five: create new exception handler with updated offsets and
// create new method body of the cci method
MethodDefinition method = methodCfg.method;
var ilGenerator = new ILGenerator(this.host, method);
// emit all operations to the new body
foreach (IOperation operation in methodOperations) {
ilGenerator.Emit(operation.OperationCode, operation.Value);
}
// list that is used to replace the pointer to the old exception handler in the basic blocks to the new exception handler
List<OldExceptionHandlerMapping> oldExceptionHandlerMappings = new List<OldExceptionHandlerMapping>();
// create for each old exception handler a new one with updated data
foreach (IOperationExceptionInformation exceptionHandler in method.Body.OperationExceptionInformation) {
// create mapping object for old exception handler
OldExceptionHandlerMapping oldExceptionHandlerMapping = new OldExceptionHandlerMapping();
oldExceptionHandlerMapping.oldExceptionHandler = exceptionHandler;
oldExceptionHandlerMappings.Add(oldExceptionHandlerMapping);
ILGeneratorLabel tryStart = new ILGeneratorLabel();
ILGeneratorLabel tryEnd = new ILGeneratorLabel();
ILGeneratorLabel handlerStart = new ILGeneratorLabel();
ILGeneratorLabel handlerEnd = new ILGeneratorLabel();
ILGeneratorLabel filterStart = new ILGeneratorLabel();
// search for the basic blocks that start/end the try block and handler block
foreach (BasicBlock tempBB in methodCfg.basicBlocks) {
foreach (TryBlock tempTryBlock in tempBB.tryBlocks) {
// ignore try blocks that do not belong to the current exception handler
if (tempTryBlock.exceptionHandler != exceptionHandler) {
continue;
}
// get offset of the instruction that starts the try block
if (tempTryBlock.firstBasicBlockOfTryBlock) {
tryStart.Offset = tempBB.operations.ElementAt(0).Offset;
oldExceptionHandlerMapping.tryStartOffset = tryStart.Offset;
}
// get offset of the instruction that ends the try block (always the last instruction of the basic block)
if (tempTryBlock.lastBasicBlockOfTryBlock) {
tryEnd.Offset = tempBB.operations.ElementAt(tempBB.operations.Count() - 1).Offset;
// exception handler object needs offset of the end of the instruction (not the beginning)
tryEnd.Offset += CfgBuilder.getSizeOfOperation(tempBB.operations.ElementAt(tempBB.operations.Count() - 1));
oldExceptionHandlerMapping.tryEndOffset = tryEnd.Offset;
}
}
foreach (HandlerBlock tempHandlerBlock in tempBB.handlerBlocks) {
// ignore handler blocks that do not belong to the current exception handler
if (tempHandlerBlock.exceptionHandler != exceptionHandler) {
continue;
}
// get offset ot the instruction that starts the handler block
if (tempHandlerBlock.firstBasicBlockOfHandlerBlock) {
handlerStart.Offset = tempBB.operations.ElementAt(0).Offset;
oldExceptionHandlerMapping.handlerStartOffset = handlerStart.Offset;
}
// get offset of the instruction that ends the handler block
if (tempHandlerBlock.lastBasicBlockOfHandlerBlock) {
handlerEnd.Offset = tempBB.operations.ElementAt(tempBB.operations.Count() - 1).Offset;
// exception handler object needs offset of the end of the instruction (not the beginning)
handlerEnd.Offset += CfgBuilder.getSizeOfOperation(tempBB.operations.ElementAt(tempBB.operations.Count() - 1));
oldExceptionHandlerMapping.handlerEndOffset = handlerEnd.Offset;
}
}
}
// copy the exception handler filter
filterStart.Offset = exceptionHandler.FilterDecisionStartOffset;
oldExceptionHandlerMapping.filterStartOffset = filterStart.Offset;
// add new exception handler
oldExceptionHandlerMapping.exceptionType = exceptionHandler.ExceptionType;
oldExceptionHandlerMapping.handlerKind = exceptionHandler.HandlerKind;
ilGenerator.AddExceptionHandlerInformation(exceptionHandler.HandlerKind, exceptionHandler.ExceptionType, tryStart, tryEnd, handlerStart, handlerEnd, filterStart);
}
// create the body
List<ILocalDefinition> variableListCopy = new List<ILocalDefinition>(method.Body.LocalVariables);
List<ITypeDefinition> privateHelperTypesListCopy = new List<ITypeDefinition>(method.Body.PrivateHelperTypes);
var newBody = new ILGeneratorMethodBody(ilGenerator, method.Body.LocalsAreZeroed, 8, method, variableListCopy, privateHelperTypesListCopy); // TODO dynamic max stack size?
method.Body = newBody;
// step six: replace pointer to the old exception handler with the new exception handler
// map all old exception handler to the new objects
foreach (IOperationExceptionInformation exceptionHandler in method.Body.OperationExceptionInformation) {
// search for the new exception handler object to get the mapping to the old one
bool found = false;
foreach (OldExceptionHandlerMapping oldExceptionHandlerMapping in oldExceptionHandlerMappings) {
if (oldExceptionHandlerMapping.exceptionType == exceptionHandler.ExceptionType
&& oldExceptionHandlerMapping.handlerKind == exceptionHandler.HandlerKind
&& oldExceptionHandlerMapping.filterStartOffset == exceptionHandler.FilterDecisionStartOffset
&& oldExceptionHandlerMapping.tryStartOffset == exceptionHandler.TryStartOffset
&& oldExceptionHandlerMapping.tryEndOffset == exceptionHandler.TryEndOffset
&& oldExceptionHandlerMapping.handlerStartOffset == exceptionHandler.HandlerStartOffset
&& oldExceptionHandlerMapping.handlerEndOffset == exceptionHandler.HandlerEndOffset) {
oldExceptionHandlerMapping.newExceptionHandler = exceptionHandler;
found = true;
break;
}
}
if (!found) {
throw new ArgumentException("Not able to map old exception handler to new one.");
}
}
// replace all old exception handler in the basic blocks with the new exception handler
foreach (BasicBlock tempBB in methodCfg.basicBlocks) {
// replace all exception handler in the try blocks
foreach (TryBlock tryBlock in tempBB.tryBlocks) {
foreach (OldExceptionHandlerMapping oldExceptionHandlerMapping in oldExceptionHandlerMappings) {
if (tryBlock.exceptionHandler == oldExceptionHandlerMapping.oldExceptionHandler) {
tryBlock.exceptionHandler = oldExceptionHandlerMapping.newExceptionHandler;
break;
}
}
}
// replace all exception handler in the handler blocks
foreach (HandlerBlock handlerBlock in tempBB.handlerBlocks) {
foreach (OldExceptionHandlerMapping oldExceptionHandlerMapping in oldExceptionHandlerMappings) {
if (handlerBlock.exceptionHandler == oldExceptionHandlerMapping.oldExceptionHandler) {
handlerBlock.exceptionHandler = oldExceptionHandlerMapping.newExceptionHandler;
break;
}
}
}
}
// TODO
// DEBUG
/*
// sanitize method name to store it as a file
String invalidChars = System.Text.RegularExpressions.Regex.Escape(new string(System.IO.Path.GetInvalidFileNameChars()));
String invalidRegStr = string.Format(@"([{0}]*\.+$)|([{0}]+)", invalidChars);
String fileName = System.Text.RegularExpressions.Regex.Replace(methodCfg.method.ToString(), invalidRegStr, "_");
fileName = fileName.Length >= 230 ? fileName.Substring(0, 230) : fileName;
// dump cfg created from the exit branches
System.IO.StreamWriter dotFile = new System.IO.StreamWriter("e:\\" + "\\BBUnion_" + fileName + ".dot");
// start .dot file graph
dotFile.WriteLine("digraph G {");
for (int bbuidx = 0; bbuidx < basicBlockUnions.Count(); bbuidx++) {
BasicBlockUnion basicBlockUnion = basicBlockUnions.ElementAt(bbuidx);
// write all basic blocks to .dot file
for (int idx = 0; idx < basicBlockUnion.basicBlocks.Count(); idx++) {
BasicBlock currentBasicBlock = basicBlockUnion.basicBlocks.ElementAt(idx);
// write the current basic block to the file and all its instructions
dotFile.WriteLine("BB" + bbuidx.ToString() + "_" + idx.ToString() + " [shape=record]");
bool first = true;
for (int opIdx = 0; opIdx < currentBasicBlock.operations.Count(); opIdx++) {
var operation = currentBasicBlock.operations.ElementAt(opIdx);
if (first) {
dotFile.Write("BB" + bbuidx.ToString() + "_" + idx.ToString() + " [label=\"{");
first = false;
}
else {
dotFile.Write("|");
}
// insert try block beginnings
foreach (var tryBlock in currentBasicBlock.tryBlocks) {
if (tryBlock.firstBasicBlockOfTryBlock && opIdx == 0) {
dotFile.Write("TRY START (" + tryBlock.exceptionHandler.ExceptionType.ToString() + ")|");
}
}
// insert catch block beginnings
foreach (var handlerBlock in currentBasicBlock.handlerBlocks) {
if (handlerBlock.firstBasicBlockOfHandlerBlock && opIdx == 0) {
if (handlerBlock.typeOfHandler == HandlerKind.Catch) {
dotFile.Write("CATCH START (" + handlerBlock.exceptionHandler.ExceptionType.ToString() + ")|");
}
else if (handlerBlock.typeOfHandler == HandlerKind.Finally) {
dotFile.Write("FINALLY START (" + handlerBlock.exceptionHandler.ExceptionType.ToString() + ")|");
}
else {
throw new ArgumentException("Do not know how to handle handler.");
}
}
}
// check if instruction has an argument
if (operation.Value != null) {
dotFile.Write(operation.OperationCode.ToString() + " " + operation.Value.ToString());
}
else {
dotFile.Write(operation.OperationCode.ToString());
}
// insert try block endings
foreach (var tryBlock in currentBasicBlock.tryBlocks) {
if (tryBlock.lastBasicBlockOfTryBlock && (currentBasicBlock.operations.Count() - 1) == opIdx) {
dotFile.Write("|TRY END (" + tryBlock.exceptionHandler.ExceptionType.ToString() + ")");
}
}
// insert catch block endings
foreach (var handlerBlock in currentBasicBlock.handlerBlocks) {
if (handlerBlock.lastBasicBlockOfHandlerBlock && (currentBasicBlock.operations.Count() - 1) == opIdx) {
if (handlerBlock.typeOfHandler == HandlerKind.Catch) {
dotFile.Write("|CATCH END (" + handlerBlock.exceptionHandler.ExceptionType.ToString() + ")");
}
else if (handlerBlock.typeOfHandler == HandlerKind.Finally) {
dotFile.Write("|FINALLY END (" + handlerBlock.exceptionHandler.ExceptionType.ToString() + ")");
}
else {
throw new ArgumentException("Do not know how to handle handler.");
}
}
}
}
dotFile.WriteLine("}\"]");
if ((idx + 1) < basicBlockUnion.basicBlocks.Count()) {
dotFile.WriteLine("BB" + bbuidx.ToString() + "_" + idx.ToString() + " -> BB" + bbuidx.ToString() + "_" + (idx + 1).ToString() + "[ color=\"blue\" ]");
}
}
}
// finish graph
dotFile.WriteLine("}");
dotFile.Close();
*/
}
private void GenerateSwitchInstruction(IEnumerable<ISwitchCase> switchCases, uint maxValue)
{
ILGeneratorLabel[] labels = new ILGeneratorLabel[maxValue+1];
ILGeneratorLabel defaultLabel = new ILGeneratorLabel();
for (uint i = 0; i <= maxValue; i++) labels[i] = defaultLabel;
Dictionary<ISwitchCase, ILGeneratorLabel> labelFor = new Dictionary<ISwitchCase, ILGeneratorLabel>();
bool foundDefault = false;
foreach (ISwitchCase switchCase in switchCases) {
if (switchCase.IsDefault) {
labelFor.Add(switchCase, defaultLabel);
foundDefault = true;
} else {
ILGeneratorLabel caseLabel = new ILGeneratorLabel();
uint i = (uint)((IConvertible)switchCase.Expression.Value).ToUInt64(null);
labels[i] = caseLabel;
labelFor.Add(switchCase, caseLabel);
}
}
this.generator.Emit(OperationCode.Switch, labels);
this.generator.Emit(OperationCode.Br, defaultLabel);
ILGeneratorLabel savedCurrentBreakTarget = this.currentBreakTarget;
if (!foundDefault)
this.currentBreakTarget = defaultLabel;
else
this.currentBreakTarget = new ILGeneratorLabel();
if (this.currentTryCatch != null)
this.mostNestedTryCatchFor.Add(this.currentBreakTarget, this.currentTryCatch);
foreach (ISwitchCase switchCase in switchCases) {
this.generator.MarkLabel(labelFor[switchCase]);
this.Traverse(switchCase);
}
this.generator.MarkLabel(this.currentBreakTarget);
this.currentBreakTarget = savedCurrentBreakTarget;
}
/// <summary>
/// Generates IL for the specified for statement.
/// </summary>
/// <param name="forStatement">For statement.</param>
public override void TraverseChildren(IForStatement forStatement)
{
ILGeneratorLabel savedCurrentBreakTarget = this.currentBreakTarget;
ILGeneratorLabel savedCurrentContinueTarget = this.currentContinueTarget;
this.currentBreakTarget = new ILGeneratorLabel();
this.currentContinueTarget = new ILGeneratorLabel();
if (this.currentTryCatch != null) {
this.mostNestedTryCatchFor.Add(this.currentBreakTarget, this.currentTryCatch);
this.mostNestedTryCatchFor.Add(this.currentContinueTarget, this.currentTryCatch);
}
ILGeneratorLabel conditionCheck = new ILGeneratorLabel();
ILGeneratorLabel loopStart = new ILGeneratorLabel();
this.Traverse(forStatement.InitStatements);
this.generator.Emit(OperationCode.Br, conditionCheck);
this.generator.MarkLabel(loopStart);
this.Traverse(forStatement.Body);
this.generator.MarkLabel(this.currentContinueTarget);
this.Traverse(forStatement.IncrementStatements);
this.generator.MarkLabel(conditionCheck);
this.EmitSequencePoint(forStatement.Condition.Locations);
this.VisitBranchIfTrue(forStatement.Condition, loopStart);
this.generator.MarkLabel(this.currentBreakTarget);
this.currentBreakTarget = savedCurrentBreakTarget;
this.currentContinueTarget = savedCurrentContinueTarget;
this.lastStatementWasUnconditionalTransfer = false;
}
/// <summary>
/// Generates IL for the specified do until statement.
/// </summary>
/// <param name="doUntilStatement">The do until statement.</param>
public override void TraverseChildren(IDoUntilStatement doUntilStatement)
{
ILGeneratorLabel savedCurrentBreakTarget = this.currentBreakTarget;
ILGeneratorLabel savedCurrentContinueTarget = this.currentContinueTarget;
this.currentBreakTarget = new ILGeneratorLabel();
this.currentContinueTarget = new ILGeneratorLabel();
if (this.currentTryCatch != null) {
this.mostNestedTryCatchFor.Add(this.currentBreakTarget, this.currentTryCatch);
this.mostNestedTryCatchFor.Add(this.currentContinueTarget, this.currentTryCatch);
}
this.generator.MarkLabel(this.currentContinueTarget);
this.Traverse(doUntilStatement.Body);
this.EmitSequencePoint(doUntilStatement.Condition.Locations);
this.VisitBranchIfFalse(doUntilStatement.Condition, this.currentContinueTarget);
this.generator.MarkLabel(this.currentBreakTarget);
this.currentBreakTarget = savedCurrentBreakTarget;
this.currentContinueTarget = savedCurrentContinueTarget;
this.lastStatementWasUnconditionalTransfer = false;
}
/// <summary>
/// Generates IL for the specified conditional statement.
/// </summary>
/// <param name="conditionalStatement">The conditional statement.</param>
public override void TraverseChildren(IConditionalStatement conditionalStatement)
{
this.EmitSequencePoint(conditionalStatement.Condition.Locations);
ILGeneratorLabel/*?*/ endif = null;
if (conditionalStatement.TrueBranch is IBreakStatement && !this.LabelIsOutsideCurrentExceptionBlock(this.currentBreakTarget))
this.VisitBranchIfTrue(conditionalStatement.Condition, this.currentBreakTarget);
else if (conditionalStatement.TrueBranch is IContinueStatement && !this.LabelIsOutsideCurrentExceptionBlock(this.currentContinueTarget))
this.VisitBranchIfTrue(conditionalStatement.Condition, this.currentContinueTarget);
else {
ILGeneratorLabel falseCase = new ILGeneratorLabel();
this.VisitBranchIfFalse(conditionalStatement.Condition, falseCase);
this.Traverse(conditionalStatement.TrueBranch);
if (!this.lastStatementWasUnconditionalTransfer) {
endif = new ILGeneratorLabel();
this.generator.Emit(OperationCode.Br, endif);
} else {
}
this.generator.MarkLabel(falseCase);
}
this.Traverse(conditionalStatement.FalseBranch);
if (endif != null)
this.generator.MarkLabel(endif);
this.lastStatementWasUnconditionalTransfer = false;
}
/// <summary>
/// Generates IL for the specified logical not.
/// </summary>
/// <param name="logicalNot">The logical not.</param>
public override void TraverseChildren(ILogicalNot logicalNot)
{
if (logicalNot.Operand.Type.IsValueType) {
//The type should be a primitive integer, a boolean or an enum.
this.Traverse(logicalNot.Operand);
var opsize = TypeHelper.SizeOfType(logicalNot.Operand.Type);
if (opsize == 1 || opsize == 2 || opsize == 4) {
this.generator.Emit(OperationCode.Ldc_I4_0);
this.StackSize++;
this.generator.Emit(OperationCode.Ceq);
this.StackSize--;
} else if (opsize == 8) {
this.generator.Emit(OperationCode.Ldc_I4_0);
this.StackSize++;
this.generator.Emit(OperationCode.Conv_I8);
this.generator.Emit(OperationCode.Ceq);
this.StackSize--;
} else {
Contract.Assert(opsize == 0); //If not, the CodeModel is invalid.
//the type is an unresolved reference, typically an enum, so we just don't know what size it is (at compile time, that is).
var trueCase = new ILGeneratorLabel();
var done = new ILGeneratorLabel();
this.generator.Emit(OperationCode.Brtrue_S, trueCase);
this.generator.Emit(OperationCode.Ldc_I4_0);
this.generator.Emit(OperationCode.Br_S, done);
this.generator.MarkLabel(trueCase);
this.generator.Emit(OperationCode.Ldc_I4_1);
this.generator.MarkLabel(done);
}
} else {
//pointer non null test
this.Traverse(logicalNot.Operand);
this.generator.Emit(OperationCode.Ldnull);
this.StackSize++;
this.generator.Emit(OperationCode.Ceq);
this.StackSize--;
}
}
/// <summary>
/// Generates IL code for the given for each statement for the special case where the collection is known
/// to be vector type.
/// </summary>
/// <param name="forEachStatement">The foreach statement to visit.</param>
/// <param name="arrayType">The vector type of the collection.</param>
public virtual void VisitForeachArrayElement(IForEachStatement forEachStatement, IArrayTypeReference arrayType)
{
Contract.Requires(arrayType.IsVector);
ILGeneratorLabel savedCurrentBreakTarget = this.currentBreakTarget;
ILGeneratorLabel savedCurrentContinueTarget = this.currentContinueTarget;
this.currentBreakTarget = new ILGeneratorLabel();
this.currentContinueTarget = new ILGeneratorLabel();
if (this.currentTryCatch != null) {
this.mostNestedTryCatchFor.Add(this.currentBreakTarget, this.currentTryCatch);
this.mostNestedTryCatchFor.Add(this.currentContinueTarget, this.currentTryCatch);
}
ILGeneratorLabel conditionCheck = new ILGeneratorLabel();
ILGeneratorLabel loopStart = new ILGeneratorLabel();
this.EmitSequencePoint(forEachStatement.Variable.Locations);
this.Traverse(forEachStatement.Collection);
this.generator.Emit(OperationCode.Dup);
var array = new TemporaryVariable(arrayType, this.method);
this.VisitAssignmentTo(array);
var length = new TemporaryVariable(this.host.PlatformType.SystemInt32, this.method);
this.generator.Emit(OperationCode.Ldlen);
this.generator.Emit(OperationCode.Conv_I4);
this.VisitAssignmentTo(length);
var counter = new TemporaryVariable(this.host.PlatformType.SystemInt32, this.method);
this.generator.Emit(OperationCode.Ldc_I4_0);
this.StackSize++;
this.VisitAssignmentTo(counter);
this.generator.Emit(OperationCode.Br, conditionCheck);
this.generator.MarkLabel(loopStart);
this.LoadLocal(array);
this.LoadLocal(counter);
this.LoadVectorElement(arrayType.ElementType);
this.VisitAssignmentTo(forEachStatement.Variable);
this.Traverse(forEachStatement.Body);
this.generator.MarkLabel(this.currentContinueTarget);
this.LoadLocal(counter);
this.generator.Emit(OperationCode.Ldc_I4_1);
this.StackSize++;
this.generator.Emit(OperationCode.Add);
this.StackSize--;
this.VisitAssignmentTo(counter);
this.generator.MarkLabel(conditionCheck);
this.EmitSequencePoint(forEachStatement.Collection.Locations);
this.LoadLocal(counter);
this.LoadLocal(length);
this.generator.Emit(OperationCode.Blt, loopStart);
this.generator.MarkLabel(this.currentBreakTarget);
this.currentBreakTarget = savedCurrentBreakTarget;
this.currentContinueTarget = savedCurrentContinueTarget;
}
private void InstrumentBlock(BasicBlock<Instruction> block) {
var blockOffset = block.Instructions[0].Operation.Offset;
this.ilGenerator.MarkLabel(this.GetLabelFor(blockOffset));
for (int i = 0, n = block.Instructions.Count-1; i < n; i++) {
var operation = block.Instructions[i].Operation;
this.EmitDebugInformationFor(operation);
this.ilGenerator.Emit(operation.OperationCode, operation.Value);
}
var lastOperation = block.Instructions[block.Instructions.Count-1].Operation;
this.EmitDebugInformationFor(lastOperation);
switch (lastOperation.OperationCode) {
case OperationCode.Beq:
case OperationCode.Beq_S:
case OperationCode.Bge:
case OperationCode.Bge_S:
case OperationCode.Bge_Un:
case OperationCode.Bge_Un_S:
case OperationCode.Bgt:
case OperationCode.Bgt_S:
case OperationCode.Bgt_Un:
case OperationCode.Bgt_Un_S:
case OperationCode.Ble:
case OperationCode.Ble_S:
case OperationCode.Ble_Un:
case OperationCode.Ble_Un_S:
case OperationCode.Blt:
case OperationCode.Blt_S:
case OperationCode.Blt_Un:
case OperationCode.Blt_Un_S:
case OperationCode.Bne_Un:
case OperationCode.Bne_Un_S:
case OperationCode.Brfalse:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue:
case OperationCode.Brtrue_S:
var unconditionalBranch = new ILGeneratorLabel();
var fallThrough = new ILGeneratorLabel();
this.ilGenerator.Emit(lastOperation.OperationCode, unconditionalBranch);
this.ilGenerator.Emit(OperationCode.Br_S, fallThrough);
this.ilGenerator.MarkLabel(unconditionalBranch);
this.EmitCounterIncrement(lastOperation.Offset);
this.ilGenerator.Emit(OperationCode.Br, this.GetLabelFor((uint)lastOperation.Value));
this.ilGenerator.MarkLabel(fallThrough);
this.EmitCounterIncrement(lastOperation.Offset+1);
break;
case OperationCode.Br:
case OperationCode.Br_S:
this.EmitCounterIncrement(lastOperation.Offset);
this.ilGenerator.Emit(OperationCode.Br, this.GetLabelFor((uint)lastOperation.Value));
break;
case OperationCode.Leave:
case OperationCode.Leave_S:
this.EmitCounterIncrement(lastOperation.Offset);
this.ilGenerator.Emit(OperationCode.Leave, this.GetLabelFor((uint)lastOperation.Value));
break;
case OperationCode.Endfilter:
case OperationCode.Endfinally:
case OperationCode.Jmp:
case OperationCode.Ret:
case OperationCode.Rethrow:
case OperationCode.Throw:
//No need to count the outgoing edge. Its count is the same as the number of times this block executes.
this.ilGenerator.Emit(lastOperation.OperationCode, lastOperation.Value);
break;
case OperationCode.Switch:
fallThrough = new ILGeneratorLabel();
uint[] targets = (uint[])lastOperation.Value;
ILGeneratorLabel[] counters = new ILGeneratorLabel[targets.Length];
for (int i = 0, n = counters.Length; i < n; i++) counters[i] = new ILGeneratorLabel();
this.ilGenerator.Emit(OperationCode.Switch, counters);
this.EmitCounterIncrement(lastOperation.Offset);
this.ilGenerator.Emit(OperationCode.Br, fallThrough);
for (int i = 0, n = counters.Length; i < n; i++) {
var counterLabel = counters[i];
this.ilGenerator.MarkLabel(counterLabel);
this.EmitCounterIncrement(lastOperation.Offset+1+(uint)i);
this.ilGenerator.Emit(OperationCode.Br, this.GetLabelFor(targets[i]));
}
this.ilGenerator.MarkLabel(fallThrough);
break;
default:
this.ilGenerator.Emit(lastOperation.OperationCode, lastOperation.Value);
this.EmitCounterIncrement(lastOperation.Offset);
break;
}
}
/// <summary>
/// Returns a label that represents the given offset in the original IL. This label must be marked
/// at the corresponding location in the rewritten IL.
/// </summary>
protected virtual ILGeneratorLabel GetLabelFor(uint offset) {
Contract.Ensures(Contract.Result<ILGeneratorLabel>() != null);
var result = this.labelFor[offset];
if (result == null)
this.labelFor[offset] = result = new ILGeneratorLabel();
return result;
}
private void ProcessOperations(IMethodBody methodBody) {
List<IOperation> operations = ((methodBody.Operations == null) ? new List<IOperation>(): new List<IOperation>(methodBody.Operations));
int count = operations.Count;
ILGenerator generator = new ILGenerator(this.host, methodBody.MethodDefinition);
if (this.pdbReader != null) {
foreach (var ns in this.pdbReader.GetNamespaceScopes(methodBody)) {
foreach (var uns in ns.UsedNamespaces)
generator.UseNamespace(uns.NamespaceName.Value);
}
}
this.currentGenerator = generator;
this.scopeEnumerator = this.pdbReader == null ? null : this.pdbReader.GetLocalScopes(methodBody).GetEnumerator();
this.scopeEnumeratorIsValid = this.scopeEnumerator != null && this.scopeEnumerator.MoveNext();
var methodName = MemberHelper.GetMemberSignature(methodBody.MethodDefinition, NameFormattingOptions.SmartTypeName);
#region Record all offsets that appear as part of an exception handler
Dictionary<uint, bool> offsetsUsedInExceptionInformation = new Dictionary<uint, bool>();
foreach (var exceptionInfo in methodBody.OperationExceptionInformation??Enumerable<IOperationExceptionInformation>.Empty) {
uint x = exceptionInfo.TryStartOffset;
if (!offsetsUsedInExceptionInformation.ContainsKey(x)) offsetsUsedInExceptionInformation.Add(x, true);
x = exceptionInfo.TryEndOffset;
if (!offsetsUsedInExceptionInformation.ContainsKey(x)) offsetsUsedInExceptionInformation.Add(x, true);
x = exceptionInfo.HandlerStartOffset;
if (!offsetsUsedInExceptionInformation.ContainsKey(x)) offsetsUsedInExceptionInformation.Add(x, true);
x = exceptionInfo.HandlerEndOffset;
if (!offsetsUsedInExceptionInformation.ContainsKey(x)) offsetsUsedInExceptionInformation.Add(x, true);
if (exceptionInfo.HandlerKind == HandlerKind.Filter) {
x = exceptionInfo.FilterDecisionStartOffset;
if (!offsetsUsedInExceptionInformation.ContainsKey(x)) offsetsUsedInExceptionInformation.Add(x, true);
}
}
#endregion Record all offsets that appear as part of an exception handler
Dictionary<uint, ILGeneratorLabel> offset2Label = new Dictionary<uint, ILGeneratorLabel>();
#region Pass 1: Make a label for each branch target
for (int i = 0; i < count; i++) {
IOperation op = operations[i];
switch (op.OperationCode) {
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.Br:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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.Br_S:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue_S:
case OperationCode.Leave_S:
uint x = (uint)op.Value;
if (!offset2Label.ContainsKey(x))
offset2Label.Add(x, new ILGeneratorLabel());
break;
case OperationCode.Switch:
uint[] offsets = op.Value as uint[];
foreach (var offset in offsets) {
if (!offset2Label.ContainsKey(offset))
offset2Label.Add(offset, new ILGeneratorLabel());
}
break;
default:
break;
}
}
#endregion Pass 1: Make a label for each branch target
#region Pass 2: Emit each operation, along with labels
for (int i = 0; i < count; i++) {
IOperation op = operations[i];
ILGeneratorLabel label;
this.EmitDebugInformationFor(op);
#region Mark operation if it is a label for a branch
if (offset2Label.TryGetValue(op.Offset, out label)) {
generator.MarkLabel(label);
}
#endregion Mark operation if it is a label for a branch
#region Mark operation if it is pointed to by an exception handler
bool ignore;
uint offset = op.Offset;
if (offsetsUsedInExceptionInformation.TryGetValue(offset, out ignore)) {
foreach (var exceptionInfo in methodBody.OperationExceptionInformation) {
if (offset == exceptionInfo.TryStartOffset)
generator.BeginTryBody();
// Never need to do anthing when offset == exceptionInfo.TryEndOffset because
// we pick up an EndTryBody from the HandlerEndOffset below
// generator.EndTryBody();
if (offset == exceptionInfo.HandlerStartOffset) {
switch (exceptionInfo.HandlerKind) {
case HandlerKind.Catch:
generator.BeginCatchBlock(exceptionInfo.ExceptionType);
break;
case HandlerKind.Fault:
generator.BeginFaultBlock();
break;
case HandlerKind.Filter:
generator.BeginFilterBody();
break;
case HandlerKind.Finally:
generator.BeginFinallyBlock();
break;
}
}
if (exceptionInfo.HandlerKind == HandlerKind.Filter && offset == exceptionInfo.FilterDecisionStartOffset) {
generator.BeginFilterBlock();
}
if (offset == exceptionInfo.HandlerEndOffset)
generator.EndTryBody();
}
}
#endregion Mark operation if it is pointed to by an exception handler
#region Emit operation along with any injection
switch (op.OperationCode) {
#region Branches
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.Br:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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.Br_S:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue_S:
case OperationCode.Leave_S:
generator.Emit(ILGenerator.LongVersionOf(op.OperationCode), offset2Label[(uint)op.Value]);
break;
case OperationCode.Switch:
uint[] offsets = op.Value as uint[];
ILGeneratorLabel[] labels = new ILGeneratorLabel[offsets.Length];
for (int j = 0, n = offsets.Length; j < n; j++) {
labels[j] = offset2Label[offsets[j]];
}
generator.Emit(OperationCode.Switch, labels);
break;
#endregion Branches
#region Everything else
case OperationCode.Stloc_0:
case OperationCode.Stloc_1:
case OperationCode.Stloc_2:
case OperationCode.Stloc_3:
generator.Emit(op.OperationCode);
EmitStoreLocal(generator, op);
break;
case OperationCode.Stloc:
case OperationCode.Stloc_S:
generator.Emit(op.OperationCode, op.Value);
EmitStoreLocal(generator, op);
break;
default:
if (op.Value == null) {
generator.Emit(op.OperationCode);
break;
}
var typeCode = System.Convert.GetTypeCode(op.Value);
switch (typeCode) {
case TypeCode.Byte:
generator.Emit(op.OperationCode, (byte)op.Value);
break;
case TypeCode.Double:
generator.Emit(op.OperationCode, (double)op.Value);
break;
case TypeCode.Int16:
generator.Emit(op.OperationCode, (short)op.Value);
break;
case TypeCode.Int32:
generator.Emit(op.OperationCode, (int)op.Value);
break;
case TypeCode.Int64:
generator.Emit(op.OperationCode, (long)op.Value);
break;
case TypeCode.Object:
IFieldReference fieldReference = op.Value as IFieldReference;
if (fieldReference != null) {
generator.Emit(op.OperationCode, this.Rewrite(fieldReference));
break;
}
ILocalDefinition localDefinition = op.Value as ILocalDefinition;
if (localDefinition != null) {
generator.Emit(op.OperationCode, localDefinition);
break;
}
IMethodReference methodReference = op.Value as IMethodReference;
if (methodReference != null) {
generator.Emit(op.OperationCode, this.Rewrite(methodReference));
break;
}
IParameterDefinition parameterDefinition = op.Value as IParameterDefinition;
if (parameterDefinition != null) {
generator.Emit(op.OperationCode, parameterDefinition);
break;
}
ISignature signature = op.Value as ISignature;
if (signature != null) {
generator.Emit(op.OperationCode, signature);
break;
}
ITypeReference typeReference = op.Value as ITypeReference;
if (typeReference != null) {
generator.Emit(op.OperationCode, this.Rewrite(typeReference));
break;
}
throw new ILMutatorException("Should never get here: no other IOperation argument types should exist");
case TypeCode.SByte:
generator.Emit(op.OperationCode, (sbyte)op.Value);
break;
case TypeCode.Single:
generator.Emit(op.OperationCode, (float)op.Value);
break;
case TypeCode.String:
generator.Emit(op.OperationCode, (string)op.Value);
break;
default:
// The other cases are the other enum values that TypeCode has.
// But no other argument types should be in the Operations. ILGenerator cannot handle anything else,
// so such IOperations should never exist.
//case TypeCode.Boolean:
//case TypeCode.Char:
//case TypeCode.DateTime:
//case TypeCode.DBNull:
//case TypeCode.Decimal:
//case TypeCode.Empty: // this would be the value for null, but the case when op.Value is null is handled before the switch statement
//case TypeCode.UInt16:
//case TypeCode.UInt32:
//case TypeCode.UInt64:
throw new ILMutatorException("Should never get here: no other IOperation argument types should exist");
}
break;
#endregion Everything else
}
#endregion Emit operation along with any injection
}
while (generator.InTryBody)
generator.EndTryBody();
while (this.scopeStack.Count > 0) {
this.currentGenerator.EndScope();
this.scopeStack.Pop();
}
#endregion Pass 2: Emit each operation, along with labels
}
/// <summary>
/// This method is called for all labels.
/// </summary>
/// <param name="op">The Microsoft intermediate language (MSIL) instruction that is marked as being a label.</param>
/// <param name="label">A label that can be used to designate locations in MSIL where an instruction may jump.</param>
protected virtual void RewriteLabel(IOperation op, ILGeneratorLabel label) {
Contract.Requires(this.generator != null);
Contract.Requires(op != null);
Contract.Requires(label != null);
this.generator.MarkLabel(label);
}
internal TryBody(ILGeneratorLabel start)
{
this.start = start;
}
/// <summary>
/// Generates IL for the specified try catch filter finally statement.
/// </summary>
/// <param name="tryCatchFilterFinallyStatement">The try catch filter finally statement.</param>
public override void TraverseChildren(ITryCatchFinallyStatement tryCatchFilterFinallyStatement)
{
var savedCurrentTryCatch = this.currentTryCatch;
this.currentTryCatch = tryCatchFilterFinallyStatement;
ILGeneratorLabel/*?*/ savedCurrentTryCatchFinallyEnd = this.currentTryCatchFinallyEnd;
this.currentTryCatchFinallyEnd = new ILGeneratorLabel();
this.generator.BeginTryBody();
this.Traverse(tryCatchFilterFinallyStatement.TryBody);
if (!this.lastStatementWasUnconditionalTransfer)
this.generator.Emit(OperationCode.Leave, this.currentTryCatchFinallyEnd);
this.Traverse(tryCatchFilterFinallyStatement.CatchClauses);
if (tryCatchFilterFinallyStatement.FinallyBody != null) {
this.generator.BeginFinallyBlock();
this.Traverse(tryCatchFilterFinallyStatement.FinallyBody);
this.generator.Emit(OperationCode.Endfinally);
}
if (tryCatchFilterFinallyStatement.FaultBody != null) {
this.generator.BeginFaultBlock();
this.Traverse(tryCatchFilterFinallyStatement.FaultBody);
this.generator.Emit(OperationCode.Endfinally);
}
this.generator.EndTryBody();
this.generator.MarkLabel(this.currentTryCatchFinallyEnd);
this.currentTryCatchFinallyEnd = savedCurrentTryCatchFinallyEnd;
this.currentTryCatch = savedCurrentTryCatch;
this.lastStatementWasUnconditionalTransfer = false;
}
//^ ensures InTryBody;
/// <summary>
/// Begins the body of a try statement.
/// </summary>
public void BeginTryBody()
{
ILGeneratorLabel tryBodyStart = new ILGeneratorLabel(false);
this.MarkLabel(tryBodyStart);
this.tryBodyStack.Push(new TryBody(tryBodyStart));
}
/// <summary>
/// Generates IL for the specified resource use statement.
/// </summary>
/// <param name="resourceUseStatement">The resource use statement.</param>
public override void TraverseChildren(IResourceUseStatement resourceUseStatement)
{
this.EmitSequencePoint(resourceUseStatement.Locations);
var systemIDisposable = new NamespaceTypeReference(this.host, this.host.PlatformType.SystemObject.ContainingUnitNamespace,
this.host.NameTable.GetNameFor("IDisposable"), 0, isEnum: false, isValueType: false, typeCode: PrimitiveTypeCode.NotPrimitive);
var dispose = new MethodReference(this.host, systemIDisposable, CallingConvention.Default, this.host.PlatformType.SystemVoid,
this.host.NameTable.GetNameFor("Dispose"), 0, Enumerable<IParameterTypeInformation>.Empty);
//Get resource into a local
ILocalDefinition resourceLocal;
var localDeclaration = resourceUseStatement.ResourceAcquisitions as ILocalDeclarationStatement;
if (localDeclaration != null) {
resourceLocal = localDeclaration.LocalVariable;
this.Traverse(localDeclaration.InitialValue);
} else {
var expressionStatement = (IExpressionStatement)resourceUseStatement.ResourceAcquisitions;
this.Traverse(expressionStatement.Expression);
resourceLocal = new TemporaryVariable(systemIDisposable, this.method);
}
this.VisitAssignmentTo(resourceLocal);
//try
var savedCurrentTryCatch = this.currentTryCatch;
this.currentTryCatch = resourceUseStatement;
var savedCurrentTryCatchFinallyEnd = this.currentTryCatchFinallyEnd;
this.currentTryCatchFinallyEnd = new ILGeneratorLabel();
this.generator.BeginTryBody();
this.Traverse(resourceUseStatement.Body);
if (!this.lastStatementWasUnconditionalTransfer)
this.generator.Emit(OperationCode.Leave, this.currentTryCatchFinallyEnd);
//finally
this.generator.BeginFinallyBlock();
var endOfFinally = new ILGeneratorLabel();
if (!resourceLocal.Type.IsValueType) {
this.generator.Emit(OperationCode.Ldloc, resourceLocal);
this.generator.Emit(OperationCode.Brfalse_S, endOfFinally);
}
this.generator.Emit(OperationCode.Ldloc, resourceLocal);
this.generator.Emit(OperationCode.Callvirt, dispose);
this.generator.MarkLabel(endOfFinally);
this.generator.Emit(OperationCode.Endfinally);
this.generator.EndTryBody();
this.generator.MarkLabel(this.currentTryCatchFinallyEnd);
this.currentTryCatchFinallyEnd = savedCurrentTryCatchFinallyEnd;
this.currentTryCatch = savedCurrentTryCatch;
this.lastStatementWasUnconditionalTransfer = false;
}
//^ requires InTryBody;
/// <summary>
/// Ends a try body.
/// </summary>
public void EndTryBody()
{
this.tryBodyStack.Pop();
if (this.handlers.Count > 0) {
ILGeneratorLabel handlerEnd = new ILGeneratorLabel(false);
this.MarkLabel(handlerEnd);
for (int i = this.handlers.Count-1; i >= 0; i--) {
var handler = this.handlers[i];
if (handler.HandlerEnd == null) {
handler.HandlerEnd = handlerEnd;
if (i < this.handlers.Count-1) {
this.handlers.RemoveAt(i);
this.handlers.Add(handler);
}
break;
}
}
}
}
/// <summary>
/// Performs one or more extra passes over the list of operations, changing long branches to short if possible and short branches to
/// long branches if necessary.
/// </summary>
/// <remarks>If any long branches in this.operations could have been short, they are adjusted to be short.
/// This can result in an updated version of this.operations where some branches that had to be long in the previous
/// version can now be short as well. Consequently, the adjustment process iterates until no further changes are possible.
/// Note that all decisions are made based on the offsets at the start of an iteration. </remarks>
public void AdjustBranchSizesToBestFit()
{
int adjustment;
uint numberOfAdjustments;
do
{
adjustment = 0;
numberOfAdjustments = 0;
for (int i = 0, n = this.operations.Count; i < n; i++)
{
Operation operation = this.operations[i];
uint oldOffset = operation.offset;
uint newOffset = (uint)(((int)oldOffset) + adjustment);
operation.offset = newOffset;
ILGeneratorLabel /*?*/ label = operation.value as ILGeneratorLabel;
if (label != null)
{
if (operation.OperationCode == (OperationCode)int.MaxValue)
{
//Dummy operation that serves as label definition.
label.Offset = operation.offset;
continue;
}
// REVIEW: Do we really want to do this? Should it be an optimization that is made upstream?
if (label.labelsReturnInstruction && (operation.OperationCode == OperationCode.Br || operation.OperationCode == OperationCode.Br_S))
{
numberOfAdjustments++;
adjustment -= (operation.OperationCode == OperationCode.Br ? 4 : 1);
this.operations[i] = new Operation(OperationCode.Ret, operation.offset, label.locationOfReturnInstruction, null);
continue;
}
//For backward branches, this test will compare the new offset of the label with the old offset of the current
//instruction. This is OK, because the new offset of the label will be less than or equal to its old offset.
bool isForwardBranch = label.Offset >= oldOffset;
// Short offsets are calculated from the start of the instruction *after* the current instruction, which takes up 2 bytes
// (1 for the opcode and 1 for the signed byte).
bool shortOffsetOk = isForwardBranch ? label.Offset - oldOffset <= 129 : newOffset - label.Offset <= 126;
OperationCode oldOpCode = operation.OperationCode;
if (shortOffsetOk)
{
operation.operationCode = ShortVersionOf(operation.OperationCode);
if (operation.operationCode != oldOpCode)
{
numberOfAdjustments++; adjustment -= 3;
}
}
else
{
if (operation.operationCode != LongVersionOf(operation.operationCode))
{
throw new InvalidOperationException(); //A short branch was specified for an offset that is long.
}
//The test for isForwardBranch depends on label offsets only decreasing, so it is not an option to replace the short branch with a long one.
}
if (operation.OperationCode == OperationCode.Br_S && operation.offset + 2 == label.Offset)
{
//eliminate branch to the next instruction
operation.operationCode = (OperationCode)int.MaxValue;
numberOfAdjustments++; adjustment -= 2;
}
}
}
} while (numberOfAdjustments > 0);
}
//^ requires InTryBody;
private ExceptionHandler BeginHandler(HandlerKind kind)
{
ILGeneratorLabel handlerStart = new ILGeneratorLabel(false);
this.MarkLabel(handlerStart);
TryBody currentTryBody = this.tryBodyStack.Peek();
ExceptionHandler handler = new ExceptionHandler(kind, currentTryBody, handlerStart);
if (currentTryBody.end == null)
currentTryBody.end = handlerStart;
else if (this.handlers.Count > 0) {
for (int i = this.handlers.Count-1; i >= 0; i--) {
if (this.handlers[i].HandlerEnd == null) {
this.handlers[i].HandlerEnd = handlerStart;
break;
}
}
}
this.handlers.Add(handler);
return handler;
}
/// <summary>
/// Emits the given operation at the current position of the new IL stream. Also tracks any referenced local definitions,
/// so that this.localVariables will contain the exact list of locals used in the new method body.
/// </summary>
/// <param name="operation"></param>
protected virtual void EmitOperation(IOperation operation)
{
Contract.Requires(operation != null);
var operationCode = operation.OperationCode;
var value = operation.Value;
switch (operationCode)
{
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.Br:
case OperationCode.Br_S:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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:
case OperationCode.Leave_S:
operationCode = ILGenerator.LongVersionOf(operationCode);
Contract.Assume(operation.Value is uint);
value = this.GetLabelFor(+(uint)operation.Value);
break;
case OperationCode.Switch:
uint[] offsets = operation.Value as uint[];
Contract.Assume(offsets != null);
var n = offsets.Length;
ILGeneratorLabel[] labels = new ILGeneratorLabel[n];
for (int i = 0; i < n; i++)
{
var offset = offsets[i];
labels[i] = this.GetLabelFor(offset);
}
value = labels;
break;
//Avoid the short forms because the locals can get reordered.
case OperationCode.Ldloc_0:
case OperationCode.Ldloc_1:
case OperationCode.Ldloc_2:
case OperationCode.Ldloc_3:
case OperationCode.Ldloc_S:
operationCode = OperationCode.Ldloc;
break;
case OperationCode.Ldloca_S:
operationCode = OperationCode.Ldloca;
break;
case OperationCode.Stloc_0:
case OperationCode.Stloc_1:
case OperationCode.Stloc_2:
case OperationCode.Stloc_3:
case OperationCode.Stloc_S:
operationCode = OperationCode.Stloc;
break;
}
this.generator.Emit(operationCode, value);
}
/// <summary>
/// Emits the given operation at the current position of the new IL stream. Also tracks any referenced local definitions,
/// so that this.localVariables will contain the exact list of locals used in the new method body.
/// </summary>
/// <param name="operation"></param>
protected virtual void EmitOperation(IOperation operation) {
Contract.Requires(operation != null);
var operationCode = operation.OperationCode;
var value = operation.Value;
switch (operationCode) {
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.Br:
case OperationCode.Br_S:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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:
case OperationCode.Leave_S:
operationCode = ILGenerator.LongVersionOf(operationCode);
Contract.Assume(operation.Value is uint);
value = this.GetLabelFor(+(uint)operation.Value);
break;
case OperationCode.Switch:
uint[] offsets = operation.Value as uint[];
Contract.Assume(offsets != null);
var n = offsets.Length;
ILGeneratorLabel[] labels = new ILGeneratorLabel[n];
for (int i = 0; i < n; i++) {
var offset = offsets[i];
labels[i] = this.GetLabelFor(offset);
}
value = labels;
break;
//Avoid the short forms because the locals can get reordered.
case OperationCode.Ldloc_0:
case OperationCode.Ldloc_1:
case OperationCode.Ldloc_2:
case OperationCode.Ldloc_3:
case OperationCode.Ldloc_S:
operationCode = OperationCode.Ldloc;
break;
case OperationCode.Ldloca_S:
operationCode = OperationCode.Ldloca;
break;
case OperationCode.Stloc_0:
case OperationCode.Stloc_1:
case OperationCode.Stloc_2:
case OperationCode.Stloc_3:
case OperationCode.Stloc_S:
operationCode = OperationCode.Stloc;
break;
}
this.generator.Emit(operationCode, value);
}
private void VisitBranchIfTrue(IExpression expression, ILGeneratorLabel targetLabel)
{
OperationCode branchOp = OperationCode.Brtrue;
IBinaryOperation/*?*/ binaryOperation = expression as IBinaryOperation;
bool signedPrimitive = binaryOperation != null && TypeHelper.IsSignedPrimitive(binaryOperation.LeftOperand.Type);
if (binaryOperation is IEquality) {
branchOp = OperationCode.Beq;
if (ExpressionHelper.IsIntegralZero(binaryOperation.LeftOperand) || ExpressionHelper.IsNullLiteral(binaryOperation.LeftOperand) ||
binaryOperation.LeftOperand is IDefaultValue || ExpressionHelper.IsZeroIntPtr(binaryOperation.LeftOperand)) {
branchOp = OperationCode.Brfalse;
expression = binaryOperation.RightOperand;
} else if (ExpressionHelper.IsIntegralZero(binaryOperation.RightOperand) || ExpressionHelper.IsNullLiteral(binaryOperation.RightOperand) ||
binaryOperation.RightOperand is IDefaultValue || ExpressionHelper.IsZeroIntPtr(binaryOperation.RightOperand)) {
branchOp = OperationCode.Brfalse;
expression = binaryOperation.LeftOperand;
}
} else if (binaryOperation is INotEquality) {
branchOp = OperationCode.Bne_Un;
if (ExpressionHelper.IsIntegralZero(binaryOperation.LeftOperand) || ExpressionHelper.IsNullLiteral(binaryOperation.LeftOperand) ||
binaryOperation.LeftOperand is IDefaultValue || ExpressionHelper.IsZeroIntPtr(binaryOperation.LeftOperand)) {
branchOp = OperationCode.Brtrue;
expression = binaryOperation.RightOperand;
} else if (ExpressionHelper.IsIntegralZero(binaryOperation.RightOperand) || ExpressionHelper.IsNullLiteral(binaryOperation.RightOperand) ||
binaryOperation.RightOperand is IDefaultValue || ExpressionHelper.IsZeroIntPtr(binaryOperation.RightOperand)) {
branchOp = OperationCode.Brtrue;
expression = binaryOperation.LeftOperand;
}
} else if (binaryOperation is ILessThan) branchOp = ((ILessThan)binaryOperation).IsUnsignedOrUnordered ? OperationCode.Blt_Un : OperationCode.Blt;
else if (binaryOperation is ILessThanOrEqual) branchOp = ((ILessThanOrEqual)binaryOperation).IsUnsignedOrUnordered ? OperationCode.Ble_Un : OperationCode.Ble;
else if (binaryOperation is IGreaterThan) branchOp = ((IGreaterThan)binaryOperation).IsUnsignedOrUnordered ? OperationCode.Bgt_Un : OperationCode.Bgt;
else if (binaryOperation is IGreaterThanOrEqual) branchOp = ((IGreaterThanOrEqual)binaryOperation).IsUnsignedOrUnordered ? OperationCode.Bge_Un : OperationCode.Bge;
else {
IConditional/*?*/ conditional = expression as IConditional;
if (conditional != null) {
ICompileTimeConstant/*?*/ resultIfFalse = conditional.ResultIfFalse as ICompileTimeConstant;
if (resultIfFalse != null && (ExpressionHelper.IsIntegralZero(resultIfFalse) || (resultIfFalse.Value is bool && !((bool)resultIfFalse.Value)))) {
//conditional.Condition && conditional.ResultIfTrue
ILGeneratorLabel fallThrough = new ILGeneratorLabel();
this.VisitBranchIfFalse(conditional.Condition, fallThrough);
this.VisitBranchIfTrue(conditional.ResultIfTrue, targetLabel);
this.generator.MarkLabel(fallThrough);
return;
}
ICompileTimeConstant/*?*/ resultIfTrue = conditional.ResultIfTrue as ICompileTimeConstant;
if (resultIfTrue != null && (ExpressionHelper.IsIntegralOne(resultIfTrue) || (resultIfTrue.Value is bool && (bool)resultIfTrue.Value))) {
//conditional.Condition || conditional.ResultIfFalse
this.VisitBranchIfTrue(conditional.Condition, targetLabel);
this.VisitBranchIfTrue(conditional.ResultIfFalse, targetLabel);
return;
}
}
IMethodCall/*?*/ methodCall = expression as IMethodCall;
if (methodCall != null) {
int mkey = methodCall.MethodToCall.Name.UniqueKey;
if ((mkey == this.host.NameTable.OpEquality.UniqueKey || mkey == this.host.NameTable.OpInequality.UniqueKey) &&
TypeHelper.TypesAreEquivalent(methodCall.MethodToCall.ContainingType, methodCall.Type.PlatformType.SystemMulticastDelegate)) {
List<IExpression> operands = new List<IExpression>(methodCall.Arguments);
if (operands.Count == 2) {
if (ExpressionHelper.IsNullLiteral(operands[0]))
expression = operands[1];
else if (ExpressionHelper.IsNullLiteral(operands[1]))
expression = operands[0];
if (expression != methodCall)
branchOp = methodCall.MethodToCall.Name.UniqueKey == this.host.NameTable.OpEquality.UniqueKey ? OperationCode.Brfalse : OperationCode.Brtrue;
}
}
} else {
ILogicalNot/*?*/ logicalNot = expression as ILogicalNot;
if (logicalNot != null) {
this.VisitBranchIfFalse(logicalNot.Operand, targetLabel);
return;
}
}
}
if (branchOp == OperationCode.Brfalse || branchOp == OperationCode.Brtrue) {
this.Traverse(expression);
this.StackSize--;
} else {
this.Traverse(binaryOperation.LeftOperand);
this.Traverse(binaryOperation.RightOperand);
this.StackSize-=2;
}
this.generator.Emit(branchOp, targetLabel);
}
/// <summary>
/// Emits the specified number of operations from the original method body.
/// </summary>
/// <param name="count"></param>
public void EmitOperations(int count)
{
for (int i = 0; i < count; i++)
{
IOperation op = operations[0];
operations.RemoveAt(0);
ILGeneratorLabel label;
if (op.Location is IILLocation)
MarkSequencePoint(op.Location);
// Mark operation if it is a label for a branch
if (offset2Label.TryGetValue(op.Offset, out label))
MarkLabel(label);
// Mark operation if it is pointed to by an exception handler
bool ignore;
uint offset = op.Offset;
if (offsetsUsedInExceptionInformation.TryGetValue(offset, out ignore))
{
foreach (var exceptionInfo in methodBody.OperationExceptionInformation)
{
if (offset == exceptionInfo.TryStartOffset)
BeginTryBody();
// Never need to do anthing when offset == exceptionInfo.TryEndOffset because
// we pick up an EndTryBody from the HandlerEndOffset below
// EndTryBody();
if (offset == exceptionInfo.HandlerStartOffset)
{
switch (exceptionInfo.HandlerKind)
{
case HandlerKind.Catch:
BeginCatchBlock(exceptionInfo.ExceptionType);
break;
case HandlerKind.Fault:
BeginFaultBlock();
break;
case HandlerKind.Filter:
BeginFilterBody();
break;
case HandlerKind.Finally:
BeginFinallyBlock();
break;
}
}
if (exceptionInfo.HandlerKind == HandlerKind.Filter && offset == exceptionInfo.FilterDecisionStartOffset)
BeginFilterBlock();
if (offset == exceptionInfo.HandlerEndOffset)
EndTryBody();
}
}
// Emit operation along with any injection
switch (op.OperationCode)
{
// Branches
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.Br:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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.Br_S:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue_S:
case OperationCode.Leave_S:
Emit(ILGenerator.LongVersionOf(op.OperationCode), offset2Label[(uint)op.Value]);
break;
case OperationCode.Switch:
uint[] offsets = op.Value as uint[];
ILGeneratorLabel[] labels = new ILGeneratorLabel[offsets.Length];
for (int j = 0, n = offsets.Length; j < n; j++)
{
labels[j] = offset2Label[offsets[j]];
}
Emit(OperationCode.Switch, labels);
break;
// Everything else
default:
if (op.Value == null)
{
Emit(op.OperationCode);
break;
}
var typeCode = System.Convert.GetTypeCode(op.Value);
switch (typeCode)
{
case TypeCode.Byte:
Emit(op.OperationCode, (byte)op.Value);
break;
case TypeCode.Double:
Emit(op.OperationCode, (double)op.Value);
break;
case TypeCode.Int16:
Emit(op.OperationCode, (short)op.Value);
break;
case TypeCode.Int32:
Emit(op.OperationCode, (int)op.Value);
break;
case TypeCode.Int64:
Emit(op.OperationCode, (long)op.Value);
break;
case TypeCode.Object:
IFieldReference fieldReference = op.Value as IFieldReference;
if (fieldReference != null)
{
Emit(op.OperationCode, fieldReference);
break;
}
ILocalDefinition localDefinition = op.Value as ILocalDefinition;
if (localDefinition != null)
{
Emit(op.OperationCode, localDefinition);
break;
}
IMethodReference methodReference = op.Value as IMethodReference;
if (methodReference != null)
{
Emit(op.OperationCode, methodReference);
break;
}
IParameterDefinition parameterDefinition = op.Value as IParameterDefinition;
if (parameterDefinition != null)
{
Emit(op.OperationCode, parameterDefinition);
break;
}
ISignature signature = op.Value as ISignature;
if (signature != null)
{
Emit(op.OperationCode, signature);
break;
}
ITypeReference typeReference = op.Value as ITypeReference;
if (typeReference != null)
{
Emit(op.OperationCode, typeReference);
break;
}
throw new Exception("Should never get here: no other IOperation argument types should exist");
case TypeCode.SByte:
Emit(op.OperationCode, (sbyte)op.Value);
break;
case TypeCode.Single:
Emit(op.OperationCode, (float)op.Value);
break;
case TypeCode.String:
Emit(op.OperationCode, (string)op.Value);
break;
default:
throw new Exception("Should never get here: no other IOperation argument types should exist");
}
break;
}
}
}
/// <summary>
/// Marks the Microsoft intermediate language (MSIL) stream's current position with the given label.
/// </summary>
public void MarkLabel(ILGeneratorLabel label)
{
label.Offset = this.offset;
this.operations.Add(new Operation((OperationCode)int.MaxValue, this.offset, Dummy.Location, label));
}
/// <summary>
/// This method is called for all opcodes related to branches:
/// OperationCode.Beq:
/// OperationCode.Bge:
/// OperationCode.Bge_Un:
/// OperationCode.Bgt:
/// OperationCode.Bgt_Un:
/// OperationCode.Ble:
/// OperationCode.Ble_Un:
/// OperationCode.Blt:
/// OperationCode.Blt_Un:
/// OperationCode.Bne_Un:
/// OperationCode.Br:
/// OperationCode.Brfalse:
/// OperationCode.Brtrue:
/// OperationCode.Leave:
/// OperationCode.Beq_S:
/// OperationCode.Bge_S:
/// OperationCode.Bge_Un_S:
/// OperationCode.Bgt_S:
/// OperationCode.Bgt_Un_S:
/// OperationCode.Ble_S:
/// OperationCode.Ble_Un_S:
/// OperationCode.Blt_S:
/// OperationCode.Blt_Un_S:
/// OperationCode.Bne_Un_S:
/// OperationCode.Br_S:
/// OperationCode.Brfalse_S:
/// OperationCode.Brtrue_S:
/// OperationCode.Leave_S:
/// </summary>
/// <param name="op">The Microsoft intermediate language (MSIL) instruction to be copied.</param>
protected virtual void RewriteBranch(IOperation op) {
Contract.Requires(this.generator != null);
Contract.Requires(op != null);
// handle branches
switch (op.OperationCode) {
// Branches
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.Br:
case OperationCode.Brfalse:
case OperationCode.Brtrue:
case OperationCode.Leave:
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.Br_S:
case OperationCode.Brfalse_S:
case OperationCode.Brtrue_S:
case OperationCode.Leave_S:
this.generator.Emit(ILGenerator.LongVersionOf(op.OperationCode),
this.offset2Label[(uint)op.Value]);
break;
case OperationCode.Switch:
uint[] offsets = op.Value as uint[];
ILGeneratorLabel[] labels = new ILGeneratorLabel[offsets.Length];
for (int j = 0, n = offsets.Length; j < n; j++) {
labels[j] = offset2Label[offsets[j]];
}
this.generator.Emit(OperationCode.Switch, labels);
break;
default:
throw new Exception("Only branches should be handled here");
}
}
internal TryBody(ILGeneratorLabel start)
{
this.start = start;
}