From 3dbab0f42bb22106747844dedeed51eeffedf2e0 Mon Sep 17 00:00:00 2001
From: Brian Fiete <bfiete@gmail.com>
Date: Mon, 20 Feb 2023 14:46:08 -0500
Subject: [PATCH] Fixed hotswap target memory allocation

---
 IDEHelper/WinDebugger.cpp | 36 +++++++++++++++++++++++++++---------
 IDEHelper/WinDebugger.h   |  6 ++++++
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/IDEHelper/WinDebugger.cpp b/IDEHelper/WinDebugger.cpp
index a694e127..4584c0ef 100644
--- a/IDEHelper/WinDebugger.cpp
+++ b/IDEHelper/WinDebugger.cpp
@@ -13065,7 +13065,7 @@ void WinDebugger::ReserveHotTargetMemory(int size)
 #endif
 	}
 
-	BfLogDbg("ReserveHotTargetMemory %p %d", hotTargetMemory.mPtr, hotTargetMemory.mSize);
+	BfLogDbg("ReserveHotTargetMemory %p %d\n", hotTargetMemory.mPtr, hotTargetMemory.mSize);
 	int err = GetLastError();
 	mHotTargetMemory.push_back(hotTargetMemory);
 }
@@ -13078,16 +13078,34 @@ addr_target WinDebugger::AllocHotTargetMemory(int size, bool canExecute, bool ca
 	else if (canExecute)
 		prot = PAGE_EXECUTE_READ;
 
-	auto hotTargetMemory = (HotTargetMemory*)&mHotTargetMemory.back();
-
-	if (hotTargetMemory->mPtr == 0)
-	{
-		Fail("Failed to allocate memory for hot loading");
-		return 0;
-	}
-
 	size = (size + (mPageSize - 1)) & ~(mPageSize - 1);
 	*outAllocSize = size;
+
+	HotTargetMemory* hotTargetMemory = NULL;
+	bool foundHotTargetMemory = false;
+	for (int i = mHotTargetMemory.mSize - 1; i >= BF_MAX(mHotTargetMemory.mSize - 32, 0); i--)
+	{
+		hotTargetMemory = &mHotTargetMemory[i];
+		if (hotTargetMemory->mPtr == 0)
+		{
+			Fail("Failed to allocate memory for hot loading");
+			return 0;
+		}
+
+		if (hotTargetMemory->GetSizeLeft() >= size)
+		{
+			foundHotTargetMemory = true;
+			break;
+		}
+	}
+
+	if (!foundHotTargetMemory)
+	{
+		ReserveHotTargetMemory(size);
+		foundHotTargetMemory = true;
+		hotTargetMemory = &mHotTargetMemory.back();
+	}
+
 	BF_ASSERT(hotTargetMemory->mOffset + size <= hotTargetMemory->mSize);
 	addr_target result = hotTargetMemory->mPtr + hotTargetMemory->mOffset;
 
diff --git a/IDEHelper/WinDebugger.h b/IDEHelper/WinDebugger.h
index 17fd0b90..580c91c6 100644
--- a/IDEHelper/WinDebugger.h
+++ b/IDEHelper/WinDebugger.h
@@ -301,6 +301,12 @@ public:
 	addr_target mPtr;
 	int mOffset;
 	int mSize;
+
+public:
+	int GetSizeLeft()
+	{
+		return mSize - mOffset;
+	}
 };
 
 #define WD_MEMCACHE_SIZE 8*1024