/// <summary>
/// Replaces the placeholder call in method with actual instruction sequence.
/// </summary>
/// <param name="method">The methodto process.</param>
/// <param name="repl">The function replacing the argument of placeholder call with actual instruction sequence.</param>
public static void ReplacePlaceholder(MethodDef method, Func<Instruction[], Instruction[]> repl) {
MethodTrace trace = new MethodTrace(method).Trace();
for (int i = 0; i < method.Body.Instructions.Count; i++) {
Instruction instr = method.Body.Instructions[i];
if (instr.OpCode == OpCodes.Call) {
var operand = (IMethod)instr.Operand;
if (operand.DeclaringType.FullName == mutationType &&
operand.Name == "Placeholder") {
int[] argIndexes = trace.TraceArguments(instr);
if (argIndexes == null)
throw new ArgumentException("Failed to trace placeholder argument.");
int argIndex = argIndexes[0];
Instruction[] arg = method.Body.Instructions.Skip(argIndex).Take(i - argIndex).ToArray();
for (int j = 0; j < arg.Length; j++)
method.Body.Instructions.RemoveAt(argIndex);
method.Body.Instructions.RemoveAt(argIndex);
arg = repl(arg);
for (int j = arg.Length - 1; j >= 0; j--)
method.Body.Instructions.Insert(argIndex, arg[j]);
return;
}
}
}
}
/// <inheritdoc />
public MethodTrace Trace(MethodDef method) {
if (method == null)
throw new ArgumentNullException("method");
return cache.GetValueOrDefaultLazy(method, m => cache[m] = new MethodTrace(m)).Trace();
}
LinkedList<Instruction[]> SpiltStatements(InstrBlock block, MethodTrace trace, CFContext ctx)
{
var statements = new LinkedList<Instruction[]>();
var currentStatement = new List<Instruction>();
for (int i = 0; i < block.Instructions.Count; i++) {
Instruction instr = block.Instructions[i];
currentStatement.Add(instr);
bool nextIsBrTarget = i + 1 < block.Instructions.Count && trace.IsBranchTarget(trace.OffsetToIndexMap(block.Instructions[i + 1].Offset));
if ((instr.OpCode.OpCodeType != OpCodeType.Prefix && trace.AfterStackDepths[trace.OffsetToIndexMap(instr.Offset)] == 0) &&
(nextIsBrTarget || ctx.Intensity > ctx.Random.NextDouble())) {
statements.AddLast(currentStatement.ToArray());
currentStatement.Clear();
}
}
if (currentStatement.Count > 0)
statements.AddLast(currentStatement.ToArray());
return statements;
}
