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More consolidation of instruction implementations.

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-08-28 21:18:08 +01:00
parent 329fd269ed
commit d710a28526
4 changed files with 54 additions and 63 deletions
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6
M6502/inc/mos6502.h
View File

@ -72,8 +72,6 @@ namespace EightBit {
virtual int execute(uint8_t opcode);
private:
register16_t& MEMPTR() { return m_memptr; }
void adjustZero(uint8_t datum) { clearFlag(P(), ZF, datum); }
void adjustNegative(uint8_t datum) { setFlag(P(), NF, datum & NF); }
@ -90,7 +88,7 @@ namespace EightBit {
#pragma region Addresses
void Address_Absolute() {
fetchWord(MEMPTR());
fetchWord();
}
void Address_ZeroPage() {
@ -530,8 +528,6 @@ namespace EightBit {
uint8_t s; // stack pointer
uint8_t p; // processor status
register16_t m_memptr;
std::array<int, 0x100> m_timings;
std::array<opcode_decoded_t, 0x100> m_decodedOpcodes;
};

11
M6502/src/mos6502.cpp
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@ -515,28 +515,27 @@ void EightBit::MOS6502::PLP() {
void EightBit::MOS6502::JSR_abs() {
Address_Absolute();
PC().word--;
pushWord(PC());
PC() = MEMPTR();
call();
}
void EightBit::MOS6502::RTI() {
PLP();
popWord(PC());
ret();
}
void EightBit::MOS6502::RTS() {
popWord(PC());
ret();
PC().word++;
}
void EightBit::MOS6502::JMP_abs() {
Address_Absolute();
PC() = MEMPTR();
jump();
}
void EightBit::MOS6502::JMP_ind() {
Address_Indirect();
PC() = MEMPTR();
jump();
}
void EightBit::MOS6502::BRK() {

26
inc/IntelProcessor.h
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@ -34,8 +34,6 @@ namespace EightBit {
return m_decodedOpcodes[i];
}
register16_t& MEMPTR() { return m_memptr; }
virtual void initialise();
register16_t& SP() { return sp; }
@ -68,9 +66,7 @@ namespace EightBit {
}
template<class T> static void adjustParity(uint8_t& f, uint8_t value) {
static const int lookup[0x10] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 };
auto set = lookup[highNibble(value)] + lookup[lowNibble(value)];
clearFlag(f, T::PF, set % 2);
clearFlag(f, T::PF, __popcnt(value) % 2);
}
template<class T> static void adjustSZ(uint8_t& f, uint8_t value) {
@ -127,10 +123,6 @@ namespace EightBit {
return getByte(SP().word++);
}
void fetchWord() {
Processor::fetchWord(MEMPTR());
}
//
void memptrReference() {
@ -154,15 +146,6 @@ namespace EightBit {
//
void jump() {
PC() = MEMPTR();
}
void call() {
pushWord(PC());
jump();
}
void restart(uint8_t address) {
MEMPTR().low = address;
MEMPTR().high = 0;
@ -183,11 +166,6 @@ namespace EightBit {
return conditional != 0;
}
void ret() {
popWord(MEMPTR());
jump();
}
bool returnConditional(int condition) {
if (condition)
ret();
@ -208,8 +186,6 @@ namespace EightBit {
private:
std::array<opcode_decoded_t, 0x100> m_decodedOpcodes;
register16_t m_memptr;
register16_t sp;
};
}

74
inc/Processor.h
View File

@ -7,35 +7,35 @@
namespace EightBit {
class Processor {
public:
enum Masks {
Mask1 = 0x01,
Mask2 = 0x03,
Mask3 = 0x07,
Mask4 = 0x0f,
Mask5 = 0x1f,
Mask6 = 0x3f,
Mask7 = 0x7f,
Mask8 = 0xff,
enum Bits {
Bit0 = 1,
Bit1 = Bit0 << 1,
Bit2 = Bit1 << 1,
Bit3 = Bit2 << 1,
Bit4 = Bit3 << 1,
Bit5 = Bit4 << 1,
Bit6 = Bit5 << 1,
Bit7 = Bit6 << 1,
Bit8 = Bit7 << 1,
Bit9 = Bit8 << 1,
Bit10 = Bit9 << 1,
Bit11 = Bit10 << 1,
Bit12 = Bit11 << 1,
Bit13 = Bit12 << 1,
Bit14 = Bit13 << 1,
Bit15 = Bit14 << 1,
Bit16 = Bit15 << 1,
};
enum Bits {
Bit16 = 0x10000,
Bit15 = 0x8000,
Bit14 = 0x4000,
Bit13 = 0x2000,
Bit12 = 0x1000,
Bit11 = 0x800,
Bit10 = 0x400,
Bit9 = 0x200,
Bit8 = 0x100,
Bit7 = 0x80,
Bit6 = 0x40,
Bit5 = 0x20,
Bit4 = 0x10,
Bit3 = 0x8,
Bit2 = 0x4,
Bit1 = 0x2,
Bit0 = 0x1,
enum Masks {
Mask1 = Bit1 - 1,
Mask2 = Bit2 - 1,
Mask3 = Bit3 - 1,
Mask4 = Bit4 - 1,
Mask5 = Bit5 - 1,
Mask6 = Bit6 - 1,
Mask7 = Bit7 - 1,
Mask8 = Bit8 - 1,
};
static int highNibble(int value) { return value >> 4; }
@ -47,6 +47,7 @@ namespace EightBit {
Memory& getMemory() { return m_memory; }
register16_t& PC() { return pc; }
register16_t& MEMPTR() { return m_memptr; }
bool isHalted() const { return m_halted; }
void halt() { --PC().word; m_halted = true; }
@ -84,6 +85,10 @@ namespace EightBit {
output.high = fetchByte();
}
void fetchWord() {
fetchWord(MEMPTR());
}
virtual int fetchExecute() {
return execute(fetchByte());
}
@ -107,8 +112,23 @@ namespace EightBit {
output.high = pop();
}
void jump() {
PC() = MEMPTR();
}
void call() {
pushWord(PC());
jump();
}
void ret() {
popWord(MEMPTR());
jump();
}
private:
register16_t pc;
register16_t m_memptr;
bool m_halted;
};
}