From 3bd01e211e4252a1b6ae2728c6c8579fa18a5995 Mon Sep 17 00:00:00 2001
From: Adrian Conlon <Adrian.conlon@gmail.com>
Date: Tue, 9 Jan 2018 23:30:51 +0000
Subject: [PATCH] Try to avoid so many virtual calls in the Z80 by hanging onto
 AF a little longer.

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
---
 Z80/inc/Z80.h   |  6 +++---
 Z80/src/Z80.cpp | 22 ++++++++++------------
 2 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/Z80/inc/Z80.h b/Z80/inc/Z80.h
index 63d7edc..a07dd23 100644
--- a/Z80/inc/Z80.h
+++ b/Z80/inc/Z80.h
@@ -302,9 +302,9 @@ namespace EightBit {
 
 		static void subtract(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0);
 
-		void executeCB(int x, int y, int z);
-		void executeED(int x, int y, int z, int p, int q);
-		void executeOther(int x, int y, int z, int p, int q);
+		void executeCB(uint8_t& a, uint8_t& f, int x, int y, int z);
+		void executeED(uint8_t& a, uint8_t& f, int x, int y, int z, int p, int q);
+		void executeOther(uint8_t& a, uint8_t& f, int x, int y, int z, int p, int q);
 
 		static void increment(uint8_t& f, uint8_t& operand);
 		static void decrement(uint8_t& f, uint8_t& operand);
diff --git a/Z80/src/Z80.cpp b/Z80/src/Z80.cpp
index 7cf39d1..7791d5e 100644
--- a/Z80/src/Z80.cpp
+++ b/Z80/src/Z80.cpp
@@ -710,14 +710,18 @@ int EightBit::Z80::execute(const uint8_t opcode) {
 	const auto p = decoded.p;
 	const auto q = decoded.q;
 
+	auto& af = AF();
+	auto& a = af.high;
+	auto& f = af.low;
+
 	auto prefixed = m_prefixCB || m_prefixED;
 	if (LIKELY(!prefixed)) {
-		executeOther(x, y, z, p, q);
+		executeOther(a, f, x, y, z, p, q);
 	} else {
 		if (m_prefixCB)
-			executeCB(x, y, z);
+			executeCB(a, f, x, y, z);
 		else if (m_prefixED)
-			executeED(x, y, z, p, q);
+			executeED(a, f, x, y, z, p, q);
 		else
 			UNREACHABLE;
 	}
@@ -728,9 +732,7 @@ int EightBit::Z80::execute(const uint8_t opcode) {
 	return cycles();
 }
 
-void EightBit::Z80::executeCB(const int x, const int y, const int z) {
-	auto& a = A();
-	auto& f = F();
+void EightBit::Z80::executeCB(uint8_t& a, uint8_t& f, const int x, const int y, const int z) {
 	switch (x) {
 	case 0:	{ // rot[y] r[z]
 		auto operand = LIKELY(!m_displaced) ? R(z, a) : getByte(displacedAddress());
@@ -824,9 +826,7 @@ void EightBit::Z80::executeCB(const int x, const int y, const int z) {
 	}
 }
 
-void EightBit::Z80::executeED(const int x, const int y, const int z, const int p, const int q) {
-	auto& a = A();
-	auto& f = F();
+void EightBit::Z80::executeED(uint8_t& a, uint8_t& f, const int x, const int y, const int z, const int p, const int q) {
 	switch (x) {
 	case 0:
 	case 3:	// Invalid instruction, equivalent to NONI followed by NOP
@@ -1060,9 +1060,7 @@ void EightBit::Z80::executeED(const int x, const int y, const int z, const int p
 	}
 }
 
-void EightBit::Z80::executeOther(const int x, const int y, const int z, const int p, const int q) {
-	auto& a = A();
-	auto& f = F();
+void EightBit::Z80::executeOther(uint8_t& a, uint8_t& f, const int x, const int y, const int z, const int p, const int q) {
 	switch (x) {
 	case 0:
 		switch (z) {