Introduce an IntelProcessor base class to allow known good implementation to be shared.

Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>

Intel8080/inc/Intel8080.h

@@ -2,12 +2,12 @@
 
 // Auxiliary carry logic from https://github.com/begoon/i8080-core
 
-#include "Processor.h"
+#include "IntelProcessor.h"
 #include "StatusFlags.h"
 #include "InputOutput.h"
 
 namespace EightBit {
-	class Intel8080 : public Processor {
+	class Intel8080 : public IntelProcessor {
 	public:
 		typedef std::function<void()> instruction_t;
 
@@ -69,9 +69,6 @@ namespace EightBit {
 
 		std::array<Instruction, 0x100> instructions;
 
-		std::array<bool, 8> m_halfCarryTableAdd = { { false, false, true, false, true, false, true, true } };
-		std::array<bool, 8> m_halfCarryTableSub = { { false, true, true, true, false, false, false, true } };
-
 		uint8_t a;
 		StatusFlags f;
 
@@ -104,28 +101,22 @@ namespace EightBit {
 			adjustParity(value);
 		}
 
-		int buildAuxiliaryCarryIndex(uint8_t value, int calculation) {
-			return ((A() & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
-		}
-
 		void adjustAuxiliaryCarryAdd(uint8_t value, int calculation) {
-			auto index = buildAuxiliaryCarryIndex(value, calculation);
+			F().AC = calculateHalfCarryAdd(A(), value, calculation);
-			F().AC = m_halfCarryTableAdd[index & 0x7];
 		}
 
 		void adjustAuxiliaryCarrySub(uint8_t value, int calculation) {
-			auto index = buildAuxiliaryCarryIndex(value, calculation);
+			F().AC = !calculateHalfCarrySub(A(), value, calculation);
-			F().AC = !m_halfCarryTableSub[index & 0x7];
 		}
 
 		void postIncrement(uint8_t value) {
 			adjustSZP(value);
-			F().AC = (value & 0x0f) == 0;
+			F().AC = lowNibble(value) == 0;
 		}
 
 		void postDecrement(uint8_t value) {
 			adjustSZP(value);
-			F().AC = (value & 0x0f) != 0xf;
+			F().AC = lowNibble(value) != 0xf;
 		}
 
 		static Instruction INS(instruction_t method, AddressingMode mode, std::string disassembly, int cycles);
@@ -135,14 +126,6 @@ namespace EightBit {
 
 		//
 
-		register16_t fetchWord() {
-			register16_t returned;
-			Processor::fetchWord(returned);
-			return returned;
-		}
-
-		//
-
 		void compare(uint8_t value) {
 			uint16_t subtraction = A() - value;
 			adjustSZP((uint8_t)subtraction);
@@ -164,9 +147,9 @@ namespace EightBit {
 		}
 
 		void jmpConditional(int conditional) {
-			auto destination = fetchWord();
+			fetchWord();
 			if (conditional)
-				pc = destination;
+				pc = MEMPTR();
 		}
 
 		void callConditional(int condition) {
@@ -344,22 +327,23 @@ namespace EightBit {
 		void ldax_d() { A() = m_memory.get(DE().word); }
 
 		void sta() {
-			auto destination = fetchWord();
+			fetchWord();
-			m_memory.set(destination.word, A());
+			m_memory.set(MEMPTR().word, A());
 		}
 
 		void lda() {
-			auto source = fetchWord();
+			fetchWord();
-			A() = m_memory.get(source.word);
+			A() = m_memory.get(MEMPTR().word);
 		}
 
 		void shld() {
-			auto destination = fetchWord();
+			fetchWord();
-			m_memory.setWord(destination.word, HL());
+			m_memory.setWord(MEMPTR().word, HL());
 		}
 
 		void lhld() {
-			HL() = m_memory.getWord(fetchWord().word);
+			fetchWord();
+			HL() = m_memory.getWord(MEMPTR().word);
 		}
 
 		void xchg() {
@@ -427,7 +411,7 @@ namespace EightBit {
 
 		// call
 
-		void call() {
+		virtual void call() override {
 			auto destination = m_memory.getWord(pc.word);
 			callAddress(destination.word);
 		}

Intel8080/src/Intel8080.cpp

@@ -5,7 +5,7 @@
 #include "Disassembler.h"
 
 EightBit::Intel8080::Intel8080(Memory& memory, InputOutput& ports)
-:	Processor(memory),
+:	IntelProcessor(memory),
 	a(0),
 	f(0),
 	m_interrupt(false),

LR35902/inc/LR35902.h

@@ -2,11 +2,12 @@
 
 #include <cstdint>
 
-#include "Processor.h"
+#include "IntelProcessor.h"
 #include "Bus.h"
+#include "Signal.h"
 
 namespace EightBit {
-	class LR35902 : public Processor {
+	class LR35902 : public IntelProcessor {
 	public:
 		enum StatusBits {
 			ZF = Bit7,
@@ -64,8 +65,6 @@ namespace EightBit {
 		uint8_t& H() { return HL().high; }
 		uint8_t& L() { return HL().low; }
 
-		register16_t& MEMPTR() { return m_memptr; }
-
 		virtual void reset();
 		virtual void initialise();
 
@@ -77,8 +76,6 @@ namespace EightBit {
 
 		bool m_ime;
 
-		register16_t m_memptr;
-
 		bool m_prefixCB;
 
 		bool m_stopped;
@@ -86,10 +83,6 @@ namespace EightBit {
 		std::array<bool, 8> m_halfCarryTableAdd = { { false, false, true, false, true, false, true, true } };
 		std::array<bool, 8> m_halfCarryTableSub = { { false, true, true, true, false, false, false, true } };
 
-		void fetchWord() {
-			Processor::fetchWord(MEMPTR());
-		}
-
 		int fetchExecute() {
 			return execute(fetchByte());
 		}
@@ -146,18 +139,12 @@ namespace EightBit {
 			}
 		}
 
-		int buildHalfCarryIndex(uint8_t before, uint8_t value, int calculation) {
-			return ((before & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
-		}
-
 		void adjustHalfCarryAdd(uint8_t before, uint8_t value, int calculation) {
-			auto index = buildHalfCarryIndex(before, value, calculation);
+			setFlag(HC, calculateHalfCarryAdd(before, value, calculation));
-			setFlag(HC, m_halfCarryTableAdd[index & 0x7]);
 		}
 
 		void adjustHalfCarrySub(uint8_t before, uint8_t value, int calculation) {
-			auto index = buildHalfCarryIndex(before, value, calculation);
+			setFlag(HC, calculateHalfCarrySub(before, value, calculation));
-			setFlag(HC, m_halfCarryTableSub[index & 0x7]);
 		}
 
 		void executeCB(int x, int y, int z, int p, int q);
@@ -182,7 +169,6 @@ namespace EightBit {
 		void jumpConditional(int condition);
 		void jumpConditionalFlag(int flag);
 
-		void call();
 		void callConditional(int condition);
 		void callConditionalFlag(int flag);
 

LR35902/src/LR35902.cpp

@@ -5,7 +5,7 @@
 // Half carry flag help from https://github.com/oubiwann/z80
 
 EightBit::LR35902::LR35902(Bus& memory)
-: Processor(memory),
+: IntelProcessor(memory),
   m_ime(false),
   m_prefixCB(false) {
 	MEMPTR().word = 0;
@@ -214,11 +214,6 @@ void EightBit::LR35902::returnConditionalFlag(int flag) {
 	}
 }
 
-void EightBit::LR35902::call() {
-	pushWord(pc);
-	pc = MEMPTR();
-}
-
 void EightBit::LR35902::callConditional(int condition) {
 	if (condition) {
 		call();

Z80/inc/Z80.h

@@ -2,11 +2,11 @@
 
 #include <cstdint>
 
-#include "Processor.h"
+#include "IntelProcessor.h"
 #include "InputOutput.h"
 
 namespace EightBit {
-	class Z80 : public Processor {
+	class Z80 : public IntelProcessor {
 	public:
 		enum StatusBits {
 			SF = Bit7,
@@ -82,8 +82,6 @@ namespace EightBit {
 		bool& IFF1() { return m_iff1; }
 		bool& IFF2() { return m_iff2; }
 
-		register16_t& MEMPTR() { return m_memptr; }
-
 		bool& M1() { return m1; }
 
 		void exx() {
@@ -97,7 +95,7 @@ namespace EightBit {
 		virtual void reset();
 		virtual void initialise();
 
-	private:
+	protected:
 		InputOutput& m_ports;
 
 		enum { BC_IDX, DE_IDX, HL_IDX };
@@ -117,8 +115,6 @@ namespace EightBit {
 		bool m_iff1;
 		bool m_iff2;
 
-		register16_t m_memptr;
-
 		bool m1;
 
 		bool m_prefixCB;
@@ -128,13 +124,6 @@ namespace EightBit {
 
 		int8_t m_displacement;
 
-		std::array<bool, 8> m_halfCarryTableAdd = { { false, false, true, false, true, false, true, true } };
-		std::array<bool, 8> m_halfCarryTableSub = { { false, true, true, true, false, false, false, true } };
-
-		void fetchWord() {
-			Processor::fetchWord(MEMPTR());
-		}
-
 		int fetchExecute() {
 			M1() = true;
 			return execute(fetchByteExecute());
@@ -299,18 +288,12 @@ namespace EightBit {
 			adc(hl, operand);
 		}
 
-		int buildHalfCarryIndex(uint8_t before, uint8_t value, int calculation) {
-			return ((before & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
-		}
-
 		void adjustHalfCarryAdd(uint8_t before, uint8_t value, int calculation) {
-			auto index = buildHalfCarryIndex(before, value, calculation);
+			setFlag(HC, calculateHalfCarryAdd(before, value, calculation));
-			setFlag(HC, m_halfCarryTableAdd[index & 0x7]);
 		}
 
 		void adjustHalfCarrySub(uint8_t before, uint8_t value, int calculation) {
-			auto index = buildHalfCarryIndex(before, value, calculation);
+			setFlag(HC, calculateHalfCarrySub(before, value, calculation));
-			setFlag(HC, m_halfCarryTableSub[index & 0x7]);
 		}
 
 		void adjustOverflowAdd(uint8_t before, uint8_t value, uint8_t calculation) {
@@ -362,7 +345,7 @@ namespace EightBit {
 		void jumpConditional(int condition);
 		void jumpConditionalFlag(int flag);
 
-		void call();
+		virtual void call() override;
 		void callConditional(int condition);
 		void callConditionalFlag(int flag);
 

Z80/src/Z80.cpp

@@ -5,7 +5,7 @@
 // Half carry flag help from https://github.com/oubiwann/z80
 
 EightBit::Z80::Z80(Memory& memory, InputOutput& ports)
-: Processor(memory),
+: IntelProcessor(memory),
   m_ports(ports),
   m_registerSet(0),
   m_accumulatorFlagsSet(0),
@@ -21,17 +21,16 @@ EightBit::Z80::Z80(Memory& memory, InputOutput& ports)
   m_prefixFD(false) {
 	IX().word = 0xffff;
 	IY().word = 0xffff;
-	MEMPTR().word = 0;
 }
 
 void EightBit::Z80::reset() {
-	Processor::reset();
+	IntelProcessor::reset();
 	IFF1() = IFF2() = false;
 }
 
 void EightBit::Z80::initialise() {
 
-	Processor::initialise();
+	IntelProcessor::initialise();
 
 	IM() = 0;
 
@@ -55,7 +54,6 @@ void EightBit::Z80::initialise() {
 
 	REFRESH() = 0x7f;
 	IV() = 0xff;
-	MEMPTR().word = 0;
 
 	m_prefixCB = false;
 	m_prefixDD = false;
@@ -294,8 +292,7 @@ void EightBit::Z80::returnConditionalFlag(int flag) {
 }
 
 void EightBit::Z80::call() {
-	pushWord(pc);
+	IntelProcessor::call();
-	pc = MEMPTR();
 	cycles += 7;
 }
 

inc/IntelProcessor.h

@@ -0,0 +1,53 @@
+#pragma once
+
+#include "Processor.h"
+
+namespace EightBit {
+	class IntelProcessor : public Processor
+	{
+	public:
+		virtual ~IntelProcessor();
+
+		register16_t& MEMPTR() { return m_memptr; }
+
+		virtual void initialise();
+
+	protected:
+		IntelProcessor(Memory& memory);
+
+		std::array<bool, 8> m_halfCarryTableAdd = { { false, false, true, false, true, false, true, true } };
+		std::array<bool, 8> m_halfCarryTableSub = { { false, true, true, true, false, false, false, true } };
+
+		int buildHalfCarryIndex(uint8_t before, uint8_t value, int calculation) {
+			return ((before & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
+		}
+
+		bool calculateHalfCarryAdd(uint8_t before, uint8_t value, int calculation) {
+			auto index = buildHalfCarryIndex(before, value, calculation);
+			return m_halfCarryTableAdd[index & 0x7];
+		}
+
+		bool calculateHalfCarrySub(uint8_t before, uint8_t value, int calculation) {
+			auto index = buildHalfCarryIndex(before, value, calculation);
+			return m_halfCarryTableSub[index & 0x7];
+		}
+
+		void push(uint8_t value);
+		void pushWord(register16_t value);
+
+		uint8_t pop();
+		void popWord(register16_t& output);
+
+		void fetchWord() {
+			Processor::fetchWord(MEMPTR());
+		}
+
+		virtual void call() {
+			pushWord(pc);
+			pc = MEMPTR();
+		}
+
+	private:
+		register16_t m_memptr;
+	};
+}

inc/Processor.h

@@ -44,8 +44,6 @@ namespace EightBit {
 		static uint8_t promoteNibble(uint8_t value) { return value << 4; }
 		static uint8_t demoteNibble(uint8_t value) { return highNibble(value); }
 
-		Processor(Memory& memory);
-
 		const Memory& getMemory() const { return m_memory; }
 
 		register16_t getProgramCounter() const { return pc; }
@@ -62,6 +60,8 @@ namespace EightBit {
 		void reset();
 
 	protected:
+		Processor(Memory& memory);
+
 		Memory& m_memory;
 
 		int cycles;
@@ -71,12 +71,6 @@ namespace EightBit {
 
 		bool m_halted;
 
-		void push(uint8_t value);
-		void pushWord(register16_t value);
-
-		uint8_t pop();
-		void popWord(register16_t& output);
-
 		uint8_t fetchByte() {
 			m_memory.ADDRESS().word = pc.word++;
 			return m_memory.reference();

src/EightBit.vcxproj

@@ -143,6 +143,7 @@
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClInclude Include="..\inc\EventArgs.h" />
+    <ClInclude Include="..\inc\IntelProcessor.h" />
     <ClInclude Include="..\inc\Memory.h" />
     <ClInclude Include="..\inc\Processor.h" />
     <ClInclude Include="..\inc\Signal.h" />
@@ -150,6 +151,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="EventArgs.cpp" />
+    <ClCompile Include="IntelProcessor.cpp" />
     <ClCompile Include="Memory.cpp" />
     <ClCompile Include="Processor.cpp" />
     <ClCompile Include="stdafx.cpp">

src/EightBit.vcxproj.filters

@@ -26,6 +26,9 @@
     <ClInclude Include="..\inc\Signal.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\inc\IntelProcessor.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="stdafx.cpp">
@@ -40,5 +43,8 @@
     <ClCompile Include="Processor.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="IntelProcessor.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
 </Project>

src/IntelProcessor.cpp

@@ -0,0 +1,36 @@
+#include "stdafx.h"
+#include "IntelProcessor.h"
+
+EightBit::IntelProcessor::IntelProcessor(Memory& memory)
+: Processor(memory) {
+	MEMPTR().word = 0;
+}
+
+EightBit::IntelProcessor::~IntelProcessor() {
+}
+
+void EightBit::IntelProcessor::initialise() {
+	Processor::initialise();
+	MEMPTR().word = 0;
+}
+
+
+void EightBit::IntelProcessor::push(uint8_t value) {
+	m_memory.ADDRESS().word = --sp.word;
+	m_memory.reference() = value;
+}
+
+void EightBit::IntelProcessor::pushWord(register16_t value) {
+	push(value.high);
+	push(value.low);
+}
+
+uint8_t EightBit::IntelProcessor::pop() {
+	m_memory.ADDRESS().word = sp.word++;
+	return m_memory.reference();
+}
+
+void EightBit::IntelProcessor::popWord(register16_t& output) {
+	output.low = pop();
+	output.high = pop();
+}

src/Processor.cpp

@@ -17,23 +17,3 @@ void EightBit::Processor::initialise() {
 	sp.word = 0xffff;
 	reset();
 }
-
-void EightBit::Processor::push(uint8_t value) {
-	m_memory.ADDRESS().word = --sp.word;
-	m_memory.reference() = value;
-}
-
-void EightBit::Processor::pushWord(register16_t value) {
-	push(value.high);
-	push(value.low);
-}
-
-uint8_t EightBit::Processor::pop() {
-	m_memory.ADDRESS().word = sp.word++;
-	return m_memory.reference();
-}
-
-void EightBit::Processor::popWord(register16_t& output) {
-	output.low = pop();
-	output.high = pop();
-}