private static void PatchDistributedUpdate(PatchContext ctx, MethodBase callerMethod)
{
var foundAnyIterate = false;
var msil = PatchUtilities.ReadInstructions(callerMethod).ToList();
for (var i = 0; i < msil.Count; i++)
{
var insn = msil[i];
if ((insn.OpCode != OpCodes.Callvirt && insn.OpCode != OpCodes.Call) ||
!IsDistributedIterate((insn.Operand as MsilOperandInline <MethodBase>)?.Value as MethodInfo))
{
continue;
}
foundAnyIterate = true;
// Call to Iterate(). Backtrace up the instruction stack to find the statement creating the delegate.
var foundNewDel = false;
for (var j = i - 1; j >= 1; j--)
{
var insn2 = msil[j];
if (insn2.OpCode != OpCodes.Newobj)
{
continue;
}
var ctorType = (insn2.Operand as MsilOperandInline <MethodBase>)?.Value?.DeclaringType;
if (ctorType == null || !ctorType.IsGenericType || ctorType.GetGenericTypeDefinition() != typeof(Action <>))
{
continue;
}
foundNewDel = true;
// Find the instruction loading the function pointer this delegate is created with
var ldftn = msil[j - 1];
if (ldftn.OpCode != OpCodes.Ldftn ||
!(ldftn.Operand is MsilOperandInline <MethodBase> targetMethod))
{
Log.Error(
$"Unable to find ldftn instruction for call to Iterate in {callerMethod.DeclaringType}#{callerMethod}");
}
else
{
Log.Debug(
$"Patching {targetMethod.Value.DeclaringType}#{targetMethod.Value} for {callerMethod.DeclaringType}#{callerMethod}");
PatchDistUpdateDel(ctx, targetMethod.Value);
}
break;
}
if (!foundNewDel)
{
Log.Error(
$"Unable to find new Action() call for Iterate in {callerMethod.DeclaringType}#{callerMethod}");
}
}
if (!foundAnyIterate)
{
Log.Error($"Unable to find any calls to {_distributedUpdaterIterate} in {callerMethod.DeclaringType}#{callerMethod}");
}
}
static MethodBase FindAction(MethodBase caller)
{
var msil = PatchUtilities.ReadInstructions(caller).ToList();
for (var i = 0; i < msil.Count; i++)
{
Log.Trace($"insn: {i} {msil[i]}");
var newobj = msil[i];
if (newobj.OpCode != OpCodes.Newobj)
{
continue;
}
Log.Trace("newobj found");
var newobjType = (newobj.Operand as MsilOperandInline <MethodBase>)?.Value?.DeclaringType;
if (newobjType == null)
{
continue;
}
if (newobjType != typeof(GenericLoop.VoidAction))
{
continue;
}
var ldftn = msil[i - 1];
Log.Trace($"ldftn found: {ldftn}");
if (ldftn.OpCode != OpCodes.Ldftn)
{
continue;
}
if (!(ldftn.Operand is MsilOperandInline <MethodBase> action))
{
continue;
}
return(action.Value);
}
throw new Exception("Failed to patch: action not found in FixedLoop.Run()");
}