Adding 8-bit Increment & Decrement Operations

Creating a generic function to set Negative and Zero flags with a value

CMakeLists.txt

@@ -81,7 +81,7 @@ add_executable(unit_tests
         sources/APU/Instructions/16bitArithmetic.cpp
         sources/APU/Instructions/16bitDataTransmission.cpp
         sources/APU/Instructions/8bitShiftRotation.cpp
-)
+        sources/APU/Instructions/8bitIncrementDecrement.cpp)
 
 # include criterion & coverage
 target_link_libraries(unit_tests criterion -lgcov)
@@ -173,7 +173,7 @@ add_executable(ComSquare
         sources/APU/Instructions/16bitArithmetic.cpp
         sources/APU/Instructions/16bitDataTransmission.cpp
         sources/APU/Instructions/8bitShiftRotation.cpp
-)
+        sources/APU/Instructions/8bitIncrementDecrement.cpp)
 
 target_compile_definitions(ComSquare PUBLIC DEBUGGER_ENABLED)
 

sources/APU/APU.cpp

@@ -194,6 +194,8 @@ namespace ComSquare::APU
 			return this->ASL(this->_getDirectAddrByX(), 5);
 		case 0x1C:
 			return this->ASL(this->_internalRegisters.a, 2, true);
+		case 0x1D:
+			return this->DECreg(this->_internalRegisters.x);
 		case 0x1F:
 			return this->JMP(this->_getAbsoluteAddrByX(), true);
 		case 0x20:
@@ -230,6 +232,8 @@ namespace ComSquare::APU
 			return this->ROL(this->_getAbsoluteAddrByX(), 5);
 		case 0x3C:
 			return this->ROL(this->_internalRegisters.a, 2, true);
+		case 0x3D:
+			return this->INCreg(this->_internalRegisters.x);
 		case 0x3F:
 			return this->CALL(this->_getAbsoluteAddr());
 		case 0x40:
@@ -314,6 +318,10 @@ namespace ComSquare::APU
 			return this->BBS(this->_getDirectAddr(), 4);
 		case 0x8A:
 			return this->EOR1(this->_getAbsoluteBit());
+		case 0x8B:
+			return this->DEC(this->_getDirectAddr(), 4);
+		case 0x8C:
+			return this->DEC(this->_getAbsoluteAddr(), 5);
 		case 0x8E:
 			return this->POP(this->_internalRegisters.psw);
 		case 0x90:
@@ -326,6 +334,10 @@ namespace ComSquare::APU
 			return this->BBC(this->_getDirectAddr(), 4);
 		case 0x9A:
 			return this->SUBW(this->_getDirectAddr());
+		case 0x9B:
+			return this->DEC(this->_getDirectAddrByX(), 5);
+		case 0x9C:
+			return this->DECreg(this->_internalRegisters.a);
 		case 0x9E:
 			return this->DIV();
 		case 0x9F:
@@ -340,6 +352,10 @@ namespace ComSquare::APU
 			return this->BBS(this->_getDirectAddr(), 5);
 		case 0xAA:
 			return this->MOV1(this->_getAbsoluteBit(), true);
+		case 0xAB:
+			return this->INC(this->_getDirectAddr(), 4);
+		case 0xAC:
+			return this->INC(this->_getAbsoluteAddr(), 5);
 		case 0xAE:
 			return this->POP(this->_internalRegisters.a);
 		case 0xB0:
@@ -352,6 +368,10 @@ namespace ComSquare::APU
 			return this->BBC(this->_getDirectAddr(), 5);
 		case 0xBA:
 			return this->MOVW(this->_getDirectAddr(), true);
+		case 0xBB:
+			return this->INC(this->_getDirectAddrByX(), 5);
+		case 0xBC:
+			return this->INCreg(this->_internalRegisters.a);
 		case 0xBE:
 			return this->DAS();
 		case 0xC0:
@@ -378,6 +398,8 @@ namespace ComSquare::APU
 			return this->BBC(this->_getDirectAddr(), 6);
 		case 0xDA:
 			return this->MOVW(this->_getDirectAddr());
+		case 0xDC:
+			return this->DECreg(this->_internalRegisters.y);
 		case 0xDE:
 			return this->CBNE(this->_getDirectAddrByX(), true);
 		case 0xDF:
@@ -398,6 +420,8 @@ namespace ComSquare::APU
 			return this->CLR1(this->_getDirectAddr(), 7);
 		case 0xF3:
 			return this->BBC(this->_getDirectAddr(), 7);
+		case 0xFC:
+			return this->INCreg(this->_internalRegisters.y);
 		case 0xEA:
 			return this->NOT1(this->_getAbsoluteBit());
 		case 0xED:
@@ -424,6 +448,12 @@ namespace ComSquare::APU
 			this->_paddingCycles = total - cycles;
 	}
 
+	void APU::_setNZflags(uint8_t value)
+	{
+		this->_internalRegisters.n = value & 0x80u;
+		this->_internalRegisters.z = !value;
+	}
+
 	MemoryMap::MemoryMap() :
 		Page0(0x00F0),
 		Page1(0x0100),

sources/APU/APU.hpp

@@ -174,6 +174,9 @@ namespace ComSquare::APU
 		//! @brief Get absolute offset and separate its bits
 		std::pair<uint24_t, uint24_t> _getAbsoluteBit();
 
+		//! @brief Set Negative and Zero flags with value after an instruction
+		void _setNZflags(uint8_t value);
+
 		//! @brief Execute a single instruction.
 		//! @return The number of cycles that the instruction took.
 		virtual int _executeInstruction();
@@ -302,6 +305,15 @@ namespace ComSquare::APU
 		int ROR(uint24_t operand, int cycles, bool accumulator = false);
 		//! @brief Exchange Nibbles.
 		int XCN();
+
+		//! @brief Increment a value at an address.
+		int INC(uint24_t addr, int cycles);
+		//! @brief Increment a register.
+		int INCreg(uint8_t &value);
+		//! @brief Decrement a value at an address.
+		int DEC(uint24_t addr, int cycles);
+		//! @brief Decrement a register.
+		int DECreg(uint8_t &value);
 	public:
 		explicit APU(std::shared_ptr<MemoryMap> &map);
 		APU(const APU &) = default;

sources/APU/Instructions/16bitDataTransmission.cpp

@@ -14,8 +14,7 @@ namespace ComSquare::APU
 			uint16_t value = ((this->_internalRead(addr2) << 8u) | this->_internalRead(addr));
 
 			this->_internalRegisters.ya = value;
-			this->_internalRegisters.n = value & 0x8000u;
+			this->_setNZflags(value);
-			this->_internalRegisters.z = !value;
 		}
 		else {
 			this->_internalWrite(addr, this->_internalRegisters.a);

sources/APU/Instructions/8bitIncrementDecrement.cpp

@@ -0,0 +1,40 @@
+//
+// Created by Melefo on 26/02/2020.
+//
+
+#include "../APU.hpp"
+
+namespace ComSquare::APU
+{
+	int APU::INC(uint24_t addr, int cycles)
+	{
+		uint8_t value = this->_internalRead(addr);
+
+		this->_internalWrite(addr, ++value);
+		this->_setNZflags(value);
+		return cycles;
+	}
+
+	int APU::INCreg(uint8_t &value)
+	{
+		value++;
+		this->_setNZflags(value);
+		return 2;
+	}
+
+	int APU::DEC(uint24_t addr, int cycles)
+	{
+		uint8_t value = this->_internalRead(addr);
+
+		this->_internalWrite(addr, --value);
+		this->_setNZflags(value);
+		return cycles;
+	}
+
+	int APU::DECreg(uint8_t &value)
+	{
+		value--;
+		this->_setNZflags(value);
+		return 2;
+	}
+}

sources/APU/Instructions/8bitShiftRotation.cpp

@@ -16,8 +16,7 @@ namespace ComSquare::APU
 			this->_internalRegisters.a = value;
 		else
 			this->_internalWrite(operand, value);
-		this->_internalRegisters.n = value & 0x80u;
+		this->_setNZflags(value);
-		this->_internalRegisters.z = !value;
 		return cycles;
 	}
 
@@ -46,8 +45,7 @@ namespace ComSquare::APU
 			this->_internalRegisters.a = result;
 		else
 			this->_internalWrite(operand, result);
-		this->_internalRegisters.n = result & 0x80u;
+		this->_setNZflags(result);
-		this->_internalRegisters.z = !result;
 		return cycles;
 	}
 
@@ -69,8 +67,7 @@ namespace ComSquare::APU
 	int APU::XCN()
 	{
 		this->_internalRegisters.a = (this->_internalRegisters.a >> 4u) | (this->_internalRegisters.a << 4u);
-		this->_internalRegisters.n = this->_internalRegisters.a & 0x80u;
+		this->_setNZflags(this->_internalRegisters.a);
-		this->_internalRegisters.z =  !this->_internalRegisters.a;
 		return 5;
 	}
 }

sources/APU/Instructions/Bit.cpp

@@ -28,8 +28,7 @@ namespace ComSquare::APU
 		uint8_t data = this->_internalRead(abs);
 
 		this->_internalWrite(abs, data | this->_internalRegisters.a);
-		this->_internalRegisters.n = data & 0x80u;
+		this->_setNZflags(data);
-		this->_internalRegisters.z = !data;
 		return 6;
 	}
 
@@ -38,8 +37,7 @@ namespace ComSquare::APU
 		uint8_t data = this->_internalRead(abs);
 
 		this->_internalWrite(abs, data & ~this->_internalRegisters.a);
-		this->_internalRegisters.n = data & 0x80u;
+		this->_setNZflags(data);
-		this->_internalRegisters.z = !data;
 		return 6;
 	}
 

sources/APU/Instructions/DecimalCompensation.cpp

@@ -15,8 +15,7 @@ namespace ComSquare::APU
 		if (this->_internalRegisters.h || (this->_internalRegisters.a & 0x0Fu) > 0x09) {
 			this->_internalRegisters.a += 0x06;
 		}
-		this->_internalRegisters.n = this->_internalRegisters.a & 0x80u;
+		this->_setNZflags(this->_internalRegisters.a);
-		this->_internalRegisters.z = !this->_internalRegisters.a;
 		return 3;
 	}
 
@@ -29,8 +28,7 @@ namespace ComSquare::APU
 		if (!this->_internalRegisters.h || (this->_internalRegisters.a & 0x0Fu) > 0x09) {
 			this->_internalRegisters.a -= 0x06;
 		}
-		this->_internalRegisters.n = this->_internalRegisters.a & 0x80u;
+		this->_setNZflags(this->_internalRegisters.a);
-		this->_internalRegisters.z = !this->_internalRegisters.a;
 		return 3;
 	}
 }

sources/APU/Instructions/MultiplicationDivision.cpp

@@ -28,8 +28,7 @@ namespace ComSquare::APU
 			this->_internalRegisters.a = 0xFF - (ya - (this->_internalRegisters.x << 9u)) / (0x100 - this->_internalRegisters.x);
 			this->_internalRegisters.y = this->_internalRegisters.x + (ya - (this->_internalRegisters.x << 9u)) % (0x100 - this->_internalRegisters.x);
 		}
-		this->_internalRegisters.z = !this->_internalRegisters.a;
+		this->_setNZflags(this->_internalRegisters.a);
-		this->_internalRegisters.n = this->_internalRegisters.a & 0x80u;
 		return 12;
 	}
 }

tests/APU/testAPUInstructions.cpp

@@ -891,7 +891,7 @@ Test(XVIbitDataTransmission, MOVW)
 //									//
 //////////////////////////////////////
 
-Test(VIIIShiftRotation, ASL)
+Test(VIIIbitShiftRotation, ASL)
 {
 	auto apu = Init().second.apu;
 	int result = 0;
@@ -913,7 +913,7 @@ Test(VIIIShiftRotation, ASL)
 	cr_assert_eq(apu->_internalRegisters.z, false);
 }
 
-Test(VIIIShiftRotation, LSR)
+Test(VIIIbitShiftRotation, LSR)
 {
 	auto apu = Init().second.apu;
 	int result = 0;
@@ -935,7 +935,7 @@ Test(VIIIShiftRotation, LSR)
 	cr_assert_eq(apu->_internalRegisters.z, false);
 }
 
-Test(VIIIShiftRotation, ROL)
+Test(VIIIbitShiftRotation, ROL)
 {
 	auto apu = Init().second.apu;
 	int result = 0;
@@ -957,7 +957,7 @@ Test(VIIIShiftRotation, ROL)
 	cr_assert_eq(apu->_internalRegisters.z, false);
 }
 
-Test(VIIIShiftRotation, ROR)
+Test(VIIIbitShiftRotation, ROR)
 {
 	auto apu = Init().second.apu;
 	int result = 0;
@@ -990,4 +990,64 @@ Test(VIIIShiftRotation, XCN)
 	cr_assert_eq(apu->_internalRegisters.a, 0xAA);
 	cr_assert_eq(apu->_internalRegisters.n, true);
 	cr_assert_eq(apu->_internalRegisters.z, false);
+}
+
+///////////////////////////////////////////
+//										 //
+// (VIII)8-bit Increment Decrement tests //
+//										 //
+///////////////////////////////////////////
+
+Test(VIIIbitIncrementDecrement, INC)
+{
+	auto apu = Init().second.apu;
+	int result = 0;
+
+	apu->_internalWrite(apu->_internalRegisters.pc, 0x55);
+	apu->_internalWrite(0x55, 0xDD);
+	result = apu->INC(apu->_getDirectAddr(), 4);
+	cr_assert_eq(result, 4);
+	cr_assert_eq(apu->_internalRead(0x55), 0xDE);
+	cr_assert_eq(apu->_internalRegisters.z, false);
+	cr_assert_eq(apu->_internalRegisters.n, true);
+}
+
+Test(VIIIbitIncrementDecrement, INCreg)
+{
+	auto apu = Init().second.apu;
+	int result = 0;
+
+	apu->_internalRegisters.a = 0x76;
+	result = apu->INCreg(apu->_internalRegisters.a);
+	cr_assert_eq(result, 2);
+	cr_assert_eq(apu->_internalRegisters.a, 0x77);
+	cr_assert_eq(apu->_internalRegisters.z, false);
+	cr_assert_eq(apu->_internalRegisters.n, false);
+}
+
+Test(VIIIbitIncrementDecrement, DEC)
+{
+	auto apu = Init().second.apu;
+	int result = 0;
+
+	apu->_internalWrite(apu->_internalRegisters.pc, 0x55);
+	apu->_internalWrite(0x55, 0xDD);
+	result = apu->DEC(apu->_getDirectAddr(), 4);
+	cr_assert_eq(result, 4);
+	cr_assert_eq(apu->_internalRead(0x55), 0xDC);
+	cr_assert_eq(apu->_internalRegisters.z, false);
+	cr_assert_eq(apu->_internalRegisters.n, true);
+}
+
+Test(VIIIbitIncrementDecrement, DECreg)
+{
+	auto apu = Init().second.apu;
+	int result = 0;
+
+	apu->_internalRegisters.a = 0x76;
+	result = apu->DECreg(apu->_internalRegisters.a);
+	cr_assert_eq(result, 2);
+	cr_assert_eq(apu->_internalRegisters.a, 0x75);
+	cr_assert_eq(apu->_internalRegisters.z, false);
+	cr_assert_eq(apu->_internalRegisters.n, false);
 }