From 6477d6c21eb3d8e2afbd80053beb1227e6ac5f26 Mon Sep 17 00:00:00 2001
From: Ben Vanik <ben.vanik@gmail.com>
Date: Sun, 27 Oct 2013 12:06:02 -0700
Subject: [PATCH] --scribble_heap, which memsets all allocated memory. Already
 exposing bugs.

---
 src/xenia/memory.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/xenia/memory.cc b/src/xenia/memory.cc
index b7127af34..73de43739 100644
--- a/src/xenia/memory.cc
+++ b/src/xenia/memory.cc
@@ -40,6 +40,9 @@ DEFINE_bool(
 DEFINE_uint64(
     heap_guard_pages, 0,
     "Allocate the given number of guard pages around all heap chunks.");
+DEFINE_bool(
+    scribble_heap, false,
+    "Scribble 0xCD into all allocated heap memory.");
 
 
 /**
@@ -524,6 +527,11 @@ uint32_t xe_memory_heap_t::Alloc(
         PAGE_READWRITE);
   }
 
+  if (FLAGS_scribble_heap) {
+    // Trash the memory so that we can see bad read-before-write bugs easier.
+    memset(p, 0xCD, alloc_size);
+  }
+
   return (uint32_t)((uintptr_t)p - (uintptr_t)memory->mapping_base);
 }
 
@@ -539,6 +547,11 @@ uint32_t xe_memory_heap_t::Free(uint32_t address, uint32_t size) {
     return 0;
   }
 
+  if (FLAGS_scribble_heap) {
+    // Trash the memory so that we can see bad read-before-write bugs easier.
+    memset(p, 0xDC, size);
+  }
+
   XEIGNORE(xe_mutex_lock(mutex));
   if (FLAGS_heap_guard_pages) {
     DWORD old_protect;