EightBit/Z80/inc/Z80.h
Adrian Conlon c6eb68ba13 Further return by value, rather than reference.
Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
2018-02-26 19:47:35 +00:00

398 lines
8.8 KiB
C++

#pragma once
#include <cstdint>
#include <cassert>
#include <stdexcept>
#include <Bus.h>
#include <InputOutput.h>
#include <IntelProcessor.h>
#include <Signal.h>
#include <Register.h>
#include <EightBitCompilerDefinitions.h>
namespace EightBit {
class Z80 final : public IntelProcessor {
public:
struct refresh_t {
bool high : 1;
uint8_t variable : 7;
refresh_t(uint8_t value)
: high((value & Bit7) != 0),
variable(value & Mask7)
{ }
operator uint8_t() const {
return (high << 7) | variable;
}
refresh_t& operator++() {
++variable;
return *this;
}
};
enum StatusBits {
SF = Bit7,
ZF = Bit6,
YF = Bit5,
HC = Bit4,
XF = Bit3,
PF = Bit2,
VF = Bit2,
NF = Bit1,
CF = Bit0,
};
Z80(Bus& bus, InputOutput& ports);
Signal<Z80> ExecutingInstruction;
PinLevel& M1() { return m_m1Line; } // Out
virtual int execute(uint8_t opcode) final;
virtual int step() final;
virtual register16_t& AF() final;
virtual register16_t& BC() final;
virtual register16_t& DE() final;
virtual register16_t& HL() final;
register16_t& IX() { return m_ix; }
uint8_t& IXH() { return IX().high; }
uint8_t& IXL() { return IX().low; }
register16_t& IY() { return m_iy; }
uint8_t& IYH() { return IY().high; }
uint8_t& IYL() { return IY().low; }
refresh_t& REFRESH() { return m_refresh; }
uint8_t& IV() { return iv; }
int& IM() { return m_interruptMode; }
bool& IFF1() { return m_iff1; }
bool& IFF2() { return m_iff2; }
void exx() {
m_registerSet ^= 1;
}
void exxAF() {
m_accumulatorFlagsSet = !m_accumulatorFlagsSet;
}
protected:
virtual void reset() final;
private:
PinLevel m_m1Line = Low;
InputOutput& m_ports;
enum { BC_IDX, DE_IDX, HL_IDX };
std::array<std::array<register16_t, 3>, 2> m_registers;
int m_registerSet = 0;
std::array<register16_t, 2> m_accumulatorFlags;
int m_accumulatorFlagsSet = 0;
register16_t m_ix = { { 0xff, 0xff } };
register16_t m_iy = { { 0xff, 0xff } };
refresh_t m_refresh = 0x7f;
uint8_t iv = 0xff;
int m_interruptMode = 0;
bool m_iff1 = false;
bool m_iff2 = false;
bool m_prefixCB = false;
bool m_prefixDD = false;
bool m_prefixED = false;
bool m_prefixFD = false;
int8_t m_displacement = 0;
bool m_displaced = false;
uint16_t displacedAddress() {
assert(m_displaced);
return MEMPTR().word = (m_prefixDD ? IX() : IY()).word + m_displacement;
}
void fetchDisplacement() {
m_displacement = fetchByte();
}
uint8_t R(int r, uint8_t a) {
switch (r) {
case 0:
return B();
case 1:
return C();
case 2:
return D();
case 3:
return E();
case 4:
return HL2().high;
case 5:
return HL2().low;
case 6:
return getByte(LIKELY(!m_displaced) ? HL().word : displacedAddress());
case 7:
return a;
default:
UNREACHABLE;
}
throw std::logic_error("Unhandled registry mechanism");
}
void R(int r, uint8_t& a, uint8_t value) {
switch (r) {
case 0:
B() = value;
break;
case 1:
C() = value;
break;
case 2:
D() = value;
break;
case 3:
E() = value;
break;
case 4:
HL2().high = value;
break;
case 5:
HL2().low = value;
break;
case 6:
setByte(LIKELY(!m_displaced) ? HL().word : displacedAddress(), value);
break;
case 7:
a = value;
break;
default:
UNREACHABLE;
}
}
uint8_t R2(int r, const uint8_t& a) {
switch (r) {
case 0:
return B();
case 1:
return C();
case 2:
return D();
case 3:
return E();
case 4:
return H();
case 5:
return L();
case 6:
return getByte(HL());
case 7:
return a;
default:
UNREACHABLE;
}
throw std::logic_error("Unhandled registry mechanism");
}
void R2(int r, uint8_t& a, uint8_t value) {
switch (r) {
case 0:
B() = value;
break;
case 1:
C() = value;
break;
case 2:
D() = value;
break;
case 3:
E() = value;
break;
case 4:
H() = value;
break;
case 5:
L() = value;
break;
case 6:
setByte(HL(), value);
break;
case 7:
a = value;
break;
default:
UNREACHABLE;
}
}
register16_t& RP(int rp) {
switch (rp) {
case 0:
return BC();
case 1:
return DE();
case 2:
return HL2();
case 3:
return SP();
default:
UNREACHABLE;
}
}
register16_t& HL2() {
if (LIKELY(!m_displaced))
return HL();
if (m_prefixDD)
return IX();
// Must be FD prefix
return IY();
}
register16_t& RP2(int rp) {
switch (rp) {
case 0:
return BC();
case 1:
return DE();
case 2:
return HL2();
case 3:
return AF();
default:
UNREACHABLE;
}
}
static void adjustHalfCarryAdd(uint8_t& f, uint8_t before, uint8_t value, int calculation) {
setFlag(f, HC, calculateHalfCarryAdd(before, value, calculation));
}
static void adjustHalfCarrySub(uint8_t& f, uint8_t before, uint8_t value, int calculation) {
setFlag(f, HC, calculateHalfCarrySub(before, value, calculation));
}
static void adjustOverflowAdd(uint8_t& f, uint8_t before, uint8_t value, uint8_t calculation) {
adjustOverflowAdd(f, before & SF, value & SF, calculation & SF);
}
static void adjustOverflowAdd(uint8_t& f, int beforeNegative, int valueNegative, int afterNegative) {
auto overflow = (beforeNegative == valueNegative) && (beforeNegative != afterNegative);
setFlag(f, VF, overflow);
}
static void adjustOverflowSub(uint8_t& f, uint8_t before, uint8_t value, uint8_t calculation) {
adjustOverflowSub(f, before & SF, value & SF, calculation & SF);
}
static void adjustOverflowSub(uint8_t& f, int beforeNegative, int valueNegative, int afterNegative) {
auto overflow = (beforeNegative != valueNegative) && (beforeNegative != afterNegative);
setFlag(f, VF, overflow);
}
static void subtract(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0);
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);
void di();
void ei();
void retn();
void reti();
bool jrConditionalFlag(uint8_t f, int flag);
bool returnConditionalFlag(uint8_t f, int flag);
bool jumpConditionalFlag(uint8_t f, int flag);
bool callConditionalFlag(uint8_t f, int flag);
void sbc(uint8_t& f, register16_t& operand, register16_t value);
void adc(uint8_t& f, register16_t& operand, register16_t value);
void add(uint8_t& f, register16_t& operand, register16_t value);
static void add(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0);
static void adc(uint8_t& f, uint8_t& operand, uint8_t value);
static void sub(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0);
static void sbc(uint8_t& f, uint8_t& operand, uint8_t value);
static void andr(uint8_t& f, uint8_t& operand, uint8_t value);
static void xorr(uint8_t& f, uint8_t& operand, uint8_t value);
static void orr(uint8_t& f, uint8_t& operand, uint8_t value);
static void compare(uint8_t& f, uint8_t check, uint8_t value);
static uint8_t rlc(uint8_t& f, uint8_t operand);
static uint8_t rrc(uint8_t& f, uint8_t operand);
static uint8_t rl(uint8_t& f, uint8_t operand);
static uint8_t rr(uint8_t& f, uint8_t operand);
static uint8_t sla(uint8_t& f, uint8_t operand);
static uint8_t sra(uint8_t& f, uint8_t operand);
static uint8_t sll(uint8_t& f, uint8_t operand);
static uint8_t srl(uint8_t& f, uint8_t operand);
static uint8_t bit(uint8_t& f, int n, uint8_t operand);
static uint8_t res(int n, uint8_t operand);
static uint8_t set(int n, uint8_t operand);
static void daa(uint8_t& a, uint8_t& f);
static void scf(uint8_t a, uint8_t& f);
static void ccf(uint8_t a, uint8_t& f);
static void cpl(uint8_t& a, uint8_t& f);
void xhtl(register16_t& operand);
void blockCompare(uint8_t a, uint8_t& f);
void cpi(uint8_t a, uint8_t& f);
bool cpir(uint8_t a, uint8_t& f);
void cpd(uint8_t a, uint8_t& f);
bool cpdr(uint8_t a, uint8_t& f);
void blockLoad(uint8_t a, uint8_t& f, register16_t source, register16_t destination);
void ldi(uint8_t a, uint8_t& f);
bool ldir(uint8_t a, uint8_t& f);
void ldd(uint8_t a, uint8_t& f);
bool lddr(uint8_t a, uint8_t& f);
void ini(uint8_t& f);
bool inir(uint8_t& f);
void ind(uint8_t& f);
bool indr(uint8_t& f);
void blockOut(uint8_t& f);
void outi(uint8_t& f);
bool otir(uint8_t& f);
void outd(uint8_t& f);
bool otdr(uint8_t& f);
static void neg(uint8_t& a, uint8_t& f);
void rrd(uint8_t& a, uint8_t& f);
void rld(uint8_t& a, uint8_t& f);
void writePort(uint8_t port, uint8_t a);
void writePort();
void readPort(uint8_t port, uint8_t& a);
void readPort();
};
}