diff --git a/src/gamedata/d_dehacked.cpp b/src/gamedata/d_dehacked.cpp
index b8ba618901..2e309514ca 100644
--- a/src/gamedata/d_dehacked.cpp
+++ b/src/gamedata/d_dehacked.cpp
@@ -739,7 +739,7 @@ static void (*MBFCodePointerFactories[])(FunctionCallEmitter&, int, int) =
 
 // Creates new functions for the given state so as to convert MBF-args (misc1 and misc2) into real args.
 
-void SetDehParams(FState *state, int codepointer)
+static void SetDehParams(FState *state, int codepointer, VMDisassemblyDumper &disasmdump)
 {
 	static const uint8_t regts[] = { REGT_POINTER, REGT_POINTER, REGT_POINTER };
 	int value1 = state->GetMisc1();
@@ -795,15 +795,8 @@ void SetDehParams(FState *state, int codepointer)
 		state->SetAction(sfunc);
 		sfunc->PrintableName.Format("Dehacked.%s.%d.%d", MBFCodePointers[codepointer].name.GetChars(), value1, value2);
 
-		if (Args->CheckParm("-dumpdisasm"))
-		{
-			FILE *dump = fopen("disasm.txt", "a");
-			if (dump != nullptr)
-			{
-				DumpFunction(dump, sfunc, sfunc->PrintableName.GetChars(), (int)sfunc->PrintableName.Len());
-			}
-			fclose(dump);
-		}
+		disasmdump.Write(sfunc, sfunc->PrintableName);
+
 #ifdef HAVE_VM_JIT
 		if (Args->CheckParm("-dumpjit"))
 		{
@@ -2651,10 +2644,12 @@ static void UnloadDehSupp ()
 {
 	if (--DehUseCount <= 0)
 	{
+		VMDisassemblyDumper disasmdump(VMDisassemblyDumper::Append);
+
 		// Handle MBF params here, before the required arrays are cleared
 		for (unsigned int i=0; i < MBFParamStates.Size(); i++)
 		{
-			SetDehParams(MBFParamStates[i].state, MBFParamStates[i].pointer);
+			SetDehParams(MBFParamStates[i].state, MBFParamStates[i].pointer, disasmdump);
 		}
 		MBFParamStates.Clear();
 		MBFParamStates.ShrinkToFit();
diff --git a/src/scripting/backend/vmbuilder.cpp b/src/scripting/backend/vmbuilder.cpp
index b787f8b587..8a6800d46b 100644
--- a/src/scripting/backend/vmbuilder.cpp
+++ b/src/scripting/backend/vmbuilder.cpp
@@ -809,11 +809,7 @@ VMFunction *FFunctionBuildList::AddFunction(PNamespace *gnspc, const VersionInfo
 
 void FFunctionBuildList::Build()
 {
-	int codesize = 0;
-	int datasize = 0;
-	FILE *dump = nullptr;
-
-	if (Args->CheckParm("-dumpdisasm")) dump = fopen("disasm.txt", "w");
+	VMDisassemblyDumper disasmdump(VMDisassemblyDumper::Overwrite);
 
 	for (auto &item : mItems)
 	{
@@ -900,13 +896,8 @@ void FFunctionBuildList::Build()
 					}
 				}
 
-				if (dump != nullptr)
-				{
-					DumpFunction(dump, sfunc, item.PrintableName.GetChars(), (int)item.PrintableName.Len());
-					codesize += sfunc->CodeSize;
-					datasize += sfunc->LineInfoCount * sizeof(FStatementInfo) + sfunc->ExtraSpace + sfunc->NumKonstD * sizeof(int) +
-						sfunc->NumKonstA * sizeof(void*) + sfunc->NumKonstF * sizeof(double) + sfunc->NumKonstS * sizeof(FString);
-				}
+				disasmdump.Write(sfunc, item.PrintableName);
+
 				sfunc->Unsafe = ctx.Unsafe;
 			}
 			catch (CRecoverableError &err)
@@ -916,15 +907,7 @@ void FFunctionBuildList::Build()
 			}
 		}
 		delete item.Code;
-		if (dump != nullptr)
-		{
-			fflush(dump);
-		}
-	}
-	if (dump != nullptr)
-	{
-		fprintf(dump, "\n*************************************************************************\n%i code bytes\n%i data bytes", codesize * 4, datasize);
-		fclose(dump);
+		disasmdump.Flush();
 	}
 	VMFunction::CreateRegUseInfo();
 	FScriptPosition::StrictErrors = false;
@@ -1122,3 +1105,50 @@ ExpEmit FunctionCallEmitter::EmitCall(VMFunctionBuilder *build, TArray<ExpEmit>
 	return retreg;
 }
 
+
+VMDisassemblyDumper::VMDisassemblyDumper(const FileOperationType operation)
+{
+	static const char *const DUMP_ARG_NAME = "-dumpdisasm";
+
+	if (Args->CheckParm(DUMP_ARG_NAME))
+	{
+		dump = fopen("disasm.txt", operation == Overwrite ? "w" : "a");
+		namefilter = Args->CheckValue(DUMP_ARG_NAME);
+		namefilter.ToLower();
+	}
+}
+
+VMDisassemblyDumper::~VMDisassemblyDumper()
+{
+	if (dump != nullptr)
+	{
+		fprintf(dump, "\n*************************************************************************\n%i code bytes\n%i data bytes\n", codesize * 4, datasize);
+		fclose(dump);
+	}
+}
+
+void VMDisassemblyDumper::Write(VMScriptFunction *sfunc, const FString &fname)
+{
+	if (dump != nullptr)
+	{
+		if (namefilter.Len() > 0 && fname.MakeLower().IndexOf(namefilter) == -1)
+		{
+			return;
+		}
+
+		assert(sfunc != nullptr);
+
+		DumpFunction(dump, sfunc, fname, (int)fname.Len());
+		codesize += sfunc->CodeSize;
+		datasize += sfunc->LineInfoCount * sizeof(FStatementInfo) + sfunc->ExtraSpace + sfunc->NumKonstD * sizeof(int) +
+			sfunc->NumKonstA * sizeof(void*) + sfunc->NumKonstF * sizeof(double) + sfunc->NumKonstS * sizeof(FString);
+	}
+}
+
+void VMDisassemblyDumper::Flush()
+{
+	if (dump != nullptr)
+	{
+		fflush(dump);
+	}
+}
diff --git a/src/scripting/backend/vmbuilder.h b/src/scripting/backend/vmbuilder.h
index 856e2afca3..8bb43565e6 100644
--- a/src/scripting/backend/vmbuilder.h
+++ b/src/scripting/backend/vmbuilder.h
@@ -211,4 +211,26 @@ public:
 	}
 };
 
+class VMDisassemblyDumper
+{
+public:
+	enum FileOperationType
+	{
+		Overwrite,
+		Append
+	};
+
+	explicit VMDisassemblyDumper(const FileOperationType operation);
+	~VMDisassemblyDumper();
+
+	void Write(VMScriptFunction *sfunc, const FString &fname);
+	void Flush();
+
+private:
+	FILE *dump = nullptr;
+	FString namefilter;
+	int codesize = 0;
+	int datasize = 0;
+};
+
 #endif