diff --git a/oscar64/Linker.cpp b/oscar64/Linker.cpp
index b7ee445..b47295a 100644
--- a/oscar64/Linker.cpp
+++ b/oscar64/Linker.cpp
@@ -4,7 +4,7 @@
 
 
 LinkerRegion::LinkerRegion(void)
-	: mSections(nullptr)
+	: mSections(nullptr), mFreeChunks(FreeChunk{ 0, 0 } )
 {}
 
 LinkerSection::LinkerSection(void)
@@ -176,6 +176,62 @@ void Linker::ReferenceObject(LinkerObject* obj)
 	}
 }
 
+bool LinkerRegion::Allocate(LinkerObject* lobj)
+{
+	int i = 0;
+	while (i < mFreeChunks.Size())
+	{
+		int start = (mFreeChunks[i].mStart + lobj->mAlignment - 1) & ~(lobj->mAlignment - 1);
+		int end = start + lobj->mSize;
+
+		if (end <= mFreeChunks[i].mEnd)
+		{
+			lobj->mFlags |= LOBJF_PLACED;
+			lobj->mAddress = start;
+			lobj->mRegion = this;
+
+			if (start == mFreeChunks[i].mStart)
+			{
+				if (end == mFreeChunks[i].mEnd)
+					mFreeChunks.Remove(i);
+				else
+					mFreeChunks[i].mStart = end;
+			}
+			else if (end == mFreeChunks[i].mEnd)
+			{
+				mFreeChunks[i].mEnd = start;
+			}
+			else
+			{
+				mFreeChunks.Insert(i + 1, FreeChunk{ end, mFreeChunks[i].mEnd } );
+				mFreeChunks[i].mEnd = start;
+			}
+
+			return true;
+		}
+		i++;
+	}
+
+	int start = (mStart + mUsed + lobj->mAlignment - 1) & ~(lobj->mAlignment - 1);
+	int end = start + lobj->mSize;
+
+	if (end <= mEnd)
+	{
+		lobj->mFlags |= LOBJF_PLACED;
+		lobj->mAddress = start;
+		lobj->mRegion = this;
+#if 1
+		if (start != mStart + mUsed)
+			mFreeChunks.Push( FreeChunk{ mStart + mUsed, start } );
+#endif
+		mUsed = end - mStart;
+
+		return true;
+	}
+
+	return false;
+}
+
 void Linker::Link(void)
 {
 	if (mErrors->mErrorCount == 0)
@@ -199,21 +255,18 @@ void Linker::Link(void)
 				for (int k = 0; k < lsec->mObjects.Size(); k++)
 				{
 					LinkerObject* lobj = lsec->mObjects[k];
-					if ((lobj->mFlags & LOBJF_REFERENCED) && !(lobj->mFlags & LOBJF_PLACED) && lrgn->mStart + lrgn->mUsed + lobj->mSize <= lrgn->mEnd)
+					if ((lobj->mFlags & LOBJF_REFERENCED) && !(lobj->mFlags & LOBJF_PLACED) && lrgn->Allocate(lobj) )
 					{
-						lobj->mFlags |= LOBJF_PLACED;
-						lobj->mAddress = (lrgn->mStart + lrgn->mUsed + lobj->mAlignment - 1) & ~(lobj->mAlignment - 1);
-						lrgn->mUsed = lobj->mAddress + lobj->mSize - lrgn->mStart;
-
-						lobj->mRegion = lrgn;
-
 						if (lsec->mType == LST_DATA)
 							lrgn->mNonzero = lrgn->mUsed;
 
-						if (lobj->mAddress < lsec->mStart)
-							lsec->mStart = lobj->mAddress;
-						if (lobj->mAddress + lobj->mSize > lsec->mEnd)
-							lsec->mEnd = lobj->mAddress + lobj->mSize;
+						if (lobj->mAddress + lobj->mSize == lrgn->mStart + lrgn->mUsed)
+						{
+							if (lobj->mAddress < lsec->mStart)
+								lsec->mStart = lobj->mAddress;
+							if (lobj->mAddress + lobj->mSize > lsec->mEnd)
+								lsec->mEnd = lobj->mAddress + lobj->mSize;
+						}
 					}
 				}
 			}
diff --git a/oscar64/Linker.h b/oscar64/Linker.h
index a829a23..7eb38eb 100644
--- a/oscar64/Linker.h
+++ b/oscar64/Linker.h
@@ -48,6 +48,15 @@ public:
 	GrowingArray<LinkerSection*>	mSections;
 
 	LinkerRegion(void);
+
+	struct FreeChunk
+	{
+		int	mStart, mEnd;
+	};
+
+	GrowingArray<FreeChunk>		mFreeChunks;
+	
+	bool Allocate(LinkerObject* obj);
 };
 
 static const uint32	LREF_LOWBYTE	=	0x00000001;
diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index ae178b8..a717f7c 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -9353,6 +9353,7 @@ bool NativeCodeBasicBlock::PatchAddressSumY(int at, int reg, int apos, int breg,
 		}
 		else if (mIns[i].mMode == ASMIM_INDIRECT_Y && mIns[i].mAddress == reg)
 		{
+			mIns[i].mFlags &= ~NCIF_YZERO;
 			mIns[i].mAddress = breg;
 		}
 	}
@@ -13026,17 +13027,18 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(int pass)
 						mIns[i + 2].mAddress = mIns[i + 0].mAddress;
 						progress = true;
 					}
+#if 1
 					else if (
 						mIns[i + 0].mType == ASMIT_CLC &&
 						mIns[i + 1].mType == ASMIT_LDA && mIns[i + 1].mMode == ASMIM_ZERO_PAGE &&
 						mIns[i + 2].mType == ASMIT_ADC && mIns[i + 2].mMode == ASMIM_IMMEDIATE && (mIns[i + 2].mAddress == 1 || mIns[i + 2].mAddress == 2) &&
-						mIns[i + 3].mType == ASMIT_STA && mIns[i + 3].mMode == ASMIM_ZERO_PAGE && mIns[i + 1].mAddress == mIns[i + 3].mAddress &&
+						mIns[i + 3].mType == ASMIT_STA && mIns[i + 3].mMode == ASMIM_ZERO_PAGE && 
 						mIns[i + 4].mType == ASMIT_TAY && !(mIns[i + 4].mLive & (LIVE_CPU_REG_A | LIVE_CPU_REG_C)))
 					{
 						mIns[i + 0].mType = ASMIT_NOP;
 						mIns[i + 1].mType = ASMIT_LDY; mIns[i + 1].mFlags |= LIVE_CPU_REG_Y;
 						mIns[i + 2].mType = ASMIT_INY; mIns[i + 2].mMode = ASMIM_IMPLIED; mIns[i + 2].mFlags |= LIVE_CPU_REG_Y;
-						mIns[i + 3].mType == ASMIT_STY; mIns[i + 3].mFlags |= LIVE_CPU_REG_Y;
+						mIns[i + 3].mType = ASMIT_STY; mIns[i + 3].mFlags |= LIVE_CPU_REG_Y;
 						mIns[i + 4].mType = ASMIT_NOP;
 						if (mIns[i + 2].mAddress == 2)
 						{
@@ -13045,6 +13047,7 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(int pass)
 
 						progress = true;
 					}
+#endif
 #if 1
 					else if (
 						mIns[i + 0].mType == ASMIT_LDY && mIns[i + 0].mMode == ASMIM_IMMEDIATE && mIns[i + 0].mAddress == 0 &&
@@ -14167,6 +14170,7 @@ void NativeCodeProcedure::Optimize(void)
 				changed = true;
 		}
 #endif
+#if 1
 		if (step == 3)
 		{
 			ResetVisited();
@@ -14176,6 +14180,7 @@ void NativeCodeProcedure::Optimize(void)
 			if (mEntryBlock->ReduceLocalYPressure())
 				changed = true;
 		}
+#endif
 #if 1
 		else if (step == 4)
 		{