From 39840b5fb15ea7647cc6e482e6bde6a075851120 Mon Sep 17 00:00:00 2001
From: drmortalwombat <90205530+drmortalwombat@users.noreply.github.com>
Date: Tue, 18 Feb 2025 11:35:06 +0100
Subject: [PATCH] Convert add to compare if only flags needed

---
 oscar64/NativeCodeGenerator.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index 52cf556..0fbfffd 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -47197,6 +47197,17 @@ bool NativeCodeBasicBlock::PeepHoleOptimizerIterate3(int i, int pass)
 		}
 	}
 
+	if (mIns[i + 0].mType == ASMIT_TXA && mIns[i + 1].mType == ASMIT_CLC &&
+		mIns[i + 2].mType == ASMIT_ADC && mIns[i + 2].mMode == ASMIM_IMMEDIATE &&
+		!(mIns[i + 2].mLive & LIVE_CPU_REG_A))
+	{
+		mIns[i + 0].mType = ASMIT_NOP;
+		mIns[i + 1].mType = ASMIT_NOP;
+		mIns[i + 2].mType = ASMIT_CPX; mIns[i + 2].mAddress = (256 - mIns[i + 2].mAddress) & 255;
+
+		return true;
+	}
+
 	return false;
 }