private bool InstrumentMethodCallInstruction(MethodDefinition method, Instruction instruction)
{
var methodName = $"{method.DeclaringType.FullName}::{method.Name}";
var processor = method.Body.GetILProcessor();
var calleeRef = (MethodReference)instruction.Operand;
var calleeName = $"{calleeRef.DeclaringType.FullName}::{calleeRef.Name}";
if (Constants.MethodPrefixBlackList.Any(x => calleeName.StartsWith(x)))
{
return(false);
}
if (calleeRef.DeclaringType.IsValueType)
{
return(false); // method in struct
}
var patchTarget = instruction;
var isValueType = false;
if (patchTarget.Previous != null && patchTarget.Previous.OpCode == OpCodes.Constrained)
{
patchTarget = patchTarget.Previous;
if (patchTarget.Operand is GenericInstanceType)
{
isValueType |= ((GenericInstanceType)patchTarget.Operand).IsValueType;
}
else if (patchTarget.Operand is TypeReference)
{
var typeRef = (TypeReference)patchTarget.Operand;
isValueType |= typeRef.IsValueType;
}
}
if (isValueType)
{
return(false); // method in struct
}
var signature = calleeRef.GetResolvedMethodSignature();
var isNewObj = instruction.OpCode == OpCodes.Newobj;
Instruction patchStart = null;
VariableDefinition instanceVarDef = null;
if (!isNewObj && calleeRef.HasThis)
{
instanceVarDef = new VariableDefinition(method.Module.TypeSystem.Object);
method.Body.Variables.Add(instanceVarDef);
var loadThisInstruction = MSILHelper.LocateLoadThisInstruction(processor, instruction);
if (loadThisInstruction == null)
{
return(false);
}
var patch1 = new List <Instruction>()
{
processor.Create(OpCodes.Dup),
processor.Create(OpCodes.Stloc, instanceVarDef),
};
processor.InsertAfter(loadThisInstruction, patch1);
patchStart = patch1[0];
}
VariableDefinition contextVarDef = null;
var afterMethodCallbackWillBeCalled = calleeRef.Name.Equals("Dispose");
if (afterMethodCallbackWillBeCalled)
{
contextVarDef = new VariableDefinition(method.Module.TypeSystem.Object);
method.Body.Variables.Add(contextVarDef);
}
var patch = this.GetPatchForBeforeMethodCall(
processor,
instanceVarDef,
methodName,
calleeRef,
instruction.Offset,
isValueType,
contextVarDef);
if (patchStart == null)
{
patchStart = patch[0];
}
processor.InsertBefore(patchTarget, patch);
method.UpdateInstructionReferences(patchTarget, patchStart, true);
/*
* if (contextVarDef != null)
* {
* patch = this.GetPatchForAfterMethodCall(processor, contextVarDef);
* processor.InsertAfter(instruction, patch);
* }
*/
return(true);
}
