From 22506fa68992d32b9c4a462deb9f5066e8e03c56 Mon Sep 17 00:00:00 2001
From: Marvin D <41352111+IcePixelx@users.noreply.github.com>
Date: Sat, 24 Dec 2022 16:40:04 +0100
Subject: [PATCH] Fix VEH.

* Make sure IsMaterialInternal won't be inlined.
* Fix recurssive VEH throwing.
* Check if IsMaterialInternal caused exception and ignore it.
---
 r5dev/materialsystem/cmaterialsystem.cpp |  2 +-
 r5dev/materialsystem/cmaterialsystem.h   |  2 +-
 r5dev/public/utility/crashhandler.cpp    | 45 ++++++++++++++++++++----
 3 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/r5dev/materialsystem/cmaterialsystem.cpp b/r5dev/materialsystem/cmaterialsystem.cpp
index f997c8ee..d822951f 100644
--- a/r5dev/materialsystem/cmaterialsystem.cpp
+++ b/r5dev/materialsystem/cmaterialsystem.cpp
@@ -66,7 +66,7 @@ void* __fastcall DispatchDrawCall(int64_t a1, uint64_t a2, int a3, int a4, int64
 // Input  : **pCandidate - 
 // Output : true if valid and material, false otherwise
 //-----------------------------------------------------------------------------
-bool IsMaterialInternal(void** pCandidate)
+__declspec(noinline) bool IsMaterialInternal(void** pCandidate)
 {
 	// NOTE: this is a dirty fix, but for running technically broken BSP's, this is the only fix 
 	// besides going bare metal inline assembly (which on its own isn't directly the problem, but 
diff --git a/r5dev/materialsystem/cmaterialsystem.h b/r5dev/materialsystem/cmaterialsystem.h
index 8f77eeeb..16a88a88 100644
--- a/r5dev/materialsystem/cmaterialsystem.h
+++ b/r5dev/materialsystem/cmaterialsystem.h
@@ -43,7 +43,7 @@ inline int* g_nUnfreeStreamingTextureMemory   = nullptr;
 inline int* g_nUnusableStreamingTextureMemory = nullptr;
 #endif // !DEDICATED
 
-bool IsMaterialInternal(void** pCandidate);
+__declspec(noinline) bool IsMaterialInternal(void** pCandidate);
 void CMaterialSystem_Attach();
 void CMaterialSystem_Detach();
 ///////////////////////////////////////////////////////////////////////////////
diff --git a/r5dev/public/utility/crashhandler.cpp b/r5dev/public/utility/crashhandler.cpp
index 5ddad4bd..eae264dd 100644
--- a/r5dev/public/utility/crashhandler.cpp
+++ b/r5dev/public/utility/crashhandler.cpp
@@ -8,6 +8,14 @@
 
 #ifndef _DEBUG
 
+#include "tier1/cvar.h"
+#include "vpc/keyvalues.h"
+#include "rtech/rtech_utils.h"
+#include "engine/cmodel_bsp.h"
+#include "materialsystem/cmaterialglue.h"
+#include "materialsystem/cmaterialsystem.h"
+#include "bsplib/bsplib.h"
+
 // Class is just for DLL init and DLL close, so we can actually define it here fine.
 class CCrashHandler
 {
@@ -135,6 +143,34 @@ long __stdcall ExceptionFilter(EXCEPTION_POINTERS* exceptionInfo)
 	if (g_ExceptionToString.find(exceptionInfo->ExceptionRecord->ExceptionCode) == g_ExceptionToString.end())
 		return EXCEPTION_CONTINUE_SEARCH;
 
+#ifndef _DEBUG
+	// THIS WONT WORK ON DEBUG!!!
+	// THIS IS DUE TO A JMP TABLE CREATED BY MSVC!!
+	static void* imiRetAddr = nullptr;
+	static auto find_IMI_ref = CMemory(IsMaterialInternal).FindAllCallReferences(reinterpret_cast<uintptr_t>(BuildPropStaticFrustumCullMap), 1000);
+	if (!find_IMI_ref.empty())
+	{
+		imiRetAddr = find_IMI_ref.at(0).Offset(0x5).RCast<void*>();
+	}
+#endif // _DEBUG
+
+	// Now get the callstack..
+	constexpr DWORD NUM_FRAMES_TO_CAPTURE = 60;
+	void* pStackTrace[NUM_FRAMES_TO_CAPTURE] = { 0 };
+	WORD nCapturedFrames = RtlCaptureStackBackTrace(0, NUM_FRAMES_TO_CAPTURE, pStackTrace, NULL);
+
+#ifndef _DEBUG
+	// Check if we found IMI.
+	if (imiRetAddr)
+	{
+		for (WORD i = 0; i < 10; i++)
+		{
+			if (imiRetAddr == pStackTrace[i])
+				return EXCEPTION_CONTINUE_SEARCH;
+		}
+	}
+#endif // _DEBUG
+
 	CONTEXT* pExceptionContext = exceptionInfo->ContextRecord;
 
 	// Setup message.
@@ -157,11 +193,6 @@ long __stdcall ExceptionFilter(EXCEPTION_POINTERS* exceptionInfo)
 
 	svMessage += "\r\nStacktrace:\r\n\r\n";
 
-	// Now get the callstack..
-	constexpr DWORD NUM_FRAMES_TO_CAPTURE = 60;
-	void* pStackTrace[NUM_FRAMES_TO_CAPTURE] = { 0 };
-	WORD nCapturedFrames = RtlCaptureStackBackTrace(0, NUM_FRAMES_TO_CAPTURE, pStackTrace, NULL);
-
 	for (WORD i = 0; i < nCapturedFrames; i++)
 	{
 		svMessage += GetModuleCrashOffsetAndName(reinterpret_cast<uintptr_t>(pStackTrace[i])) + "\n";
@@ -177,6 +208,8 @@ long __stdcall ExceptionFilter(EXCEPTION_POINTERS* exceptionInfo)
 
 	MessageBoxA(0, svMessage.c_str(), "R5R Crashed :/", MB_ICONERROR | MB_OK);
 
+	bLogged = true;
+
 	return EXCEPTION_EXECUTE_HANDLER;
 }
 
@@ -192,6 +225,6 @@ CCrashHandler::~CCrashHandler()
 
 // Init on DLL init!
 // Needs fixing for frustum culling, it triggers the SEH handler there which also triggers this, add address to whitelist/whitelist whole code page.
-//CCrashHandler* g_CrashHandler = new CCrashHandler();
+CCrashHandler* g_CrashHandler = new CCrashHandler();
 
 #endif // _DEBUG
\ No newline at end of file