diff --git a/oscar64/InterCode.cpp b/oscar64/InterCode.cpp
index 43b6fbe..8e002cb 100644
--- a/oscar64/InterCode.cpp
+++ b/oscar64/InterCode.cpp
@@ -7670,6 +7670,66 @@ void InterCodeBasicBlock::PerformValueForwarding(const GrowingInstructionPtrArra
 						ins->mSrc[1].mTemp = cai->mDst.mTemp;
 					}
 				}
+				else if (mi0 && mi1 && mi0->mCode == IC_CONSTANT && mi1->mCode == IC_BINARY_OPERATOR && mi1->mOperator == IA_SUB)
+				{
+					InterInstruction* ai0 = ltvalue[mi1->mSrc[0].mTemp], * ai1 = ltvalue[mi1->mSrc[1].mTemp];
+					if (ai0 && ai0->mCode == IC_CONSTANT)
+					{
+						InterInstruction* nai = new InterInstruction();
+						nai->mCode = IC_BINARY_OPERATOR;
+						nai->mOperator = IA_MUL;
+						nai->mSrc[0].mTemp = mi1->mSrc[1].mTemp;
+						nai->mSrc[0].mType = IT_INT16;
+						nai->mSrc[1].mTemp = ins->mSrc[0].mTemp;
+						nai->mSrc[1].mType = IT_INT16;
+						nai->mDst.mTemp = spareTemps++;
+						nai->mDst.mType = IT_INT16;
+						mInstructions.Insert(i, nai);
+
+						ltvalue[nai->mDst.mTemp] = nullptr;
+
+						InterInstruction* cai = new InterInstruction();
+						cai->mCode = IC_CONSTANT;
+						cai->mDst.mTemp = spareTemps++;
+						cai->mDst.mType = IT_INT16;
+						cai->mConst.mIntConst = ai0->mConst.mIntConst * mi0->mConst.mIntConst;
+						mInstructions.Insert(i, cai);
+
+						ltvalue[cai->mDst.mTemp] = nullptr;
+
+						ins->mOperator = IA_SUB;
+						ins->mSrc[1].mTemp = nai->mDst.mTemp;
+						ins->mSrc[0].mTemp = cai->mDst.mTemp;
+					}
+					else if (ai1 && ai1->mCode == IC_CONSTANT)
+					{
+						InterInstruction* nai = new InterInstruction();
+						nai->mCode = IC_BINARY_OPERATOR;
+						nai->mOperator = IA_MUL;
+						nai->mSrc[0].mTemp = mi1->mSrc[0].mTemp;
+						nai->mSrc[0].mType = IT_INT16;
+						nai->mSrc[1].mTemp = ins->mSrc[0].mTemp;
+						nai->mSrc[1].mType = IT_INT16;
+						nai->mDst.mTemp = spareTemps++;
+						nai->mDst.mType = IT_INT16;
+						mInstructions.Insert(i, nai);
+
+						ltvalue[nai->mDst.mTemp] = nullptr;
+
+						InterInstruction* cai = new InterInstruction();
+						cai->mCode = IC_CONSTANT;
+						cai->mDst.mTemp = spareTemps++;
+						cai->mDst.mType = IT_INT16;
+						cai->mConst.mIntConst = ai1->mConst.mIntConst * mi0->mConst.mIntConst;
+						mInstructions.Insert(i, cai);
+
+						ltvalue[cai->mDst.mTemp] = nullptr;
+
+						ins->mOperator = IA_SUB;
+						ins->mSrc[1].mTemp = nai->mDst.mTemp;
+						ins->mSrc[0].mTemp = cai->mDst.mTemp;
+					}
+				}
 			}
 #endif
 #if 1
@@ -12568,6 +12628,8 @@ void InterCodeProcedure::Close(void)
 		ResetVisited();
 		mEntryBlock->PerformValueForwarding(mValueForwardingTable, valueSet, tvalidSet, mLocalAliasedSet, mParamAliasedSet, numTemps, mModule->mGlobalVars);
 
+		DisassembleDebug("PerformValueForwarding");
+
 		ResetVisited();
 		eliminated = mEntryBlock->EliminateDeadBranches();
 		if (eliminated)
diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index a8cf622..b7427e3 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -24657,6 +24657,7 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(NativeCodeProcedure* proc, int pass
 						(mIns[i + 0].mType == ASMIT_INX || mIns[i + 0].mType == ASMIT_DEX) &&
 						mIns[i + 1].mType == ASMIT_TXA && !(mIns[i + 1].mLive & LIVE_CPU_REG_A))
 					{
+						mIns[i + 0].mLive |= LIVE_CPU_REG_Z;
 						mIns[i + 1].mType = ASMIT_NOP; mIns[i + 1].mMode = ASMIM_IMPLIED;
 						progress = true;
 					}
@@ -24664,6 +24665,7 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(NativeCodeProcedure* proc, int pass
 						(mIns[i + 0].mType == ASMIT_INY || mIns[i + 0].mType == ASMIT_DEY) &&
 						mIns[i + 1].mType == ASMIT_TYA && !(mIns[i + 1].mLive & LIVE_CPU_REG_A))
 					{
+						mIns[i + 0].mLive |= LIVE_CPU_REG_Z;
 						mIns[i + 1].mType = ASMIT_NOP; mIns[i + 1].mMode = ASMIM_IMPLIED;
 						progress = true;
 					}