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Simplification of bitwise operators.

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Signed-off-by: Adrian.Conlon <adrian.conlon@arup.com>
This commit is contained in:
Adrian.Conlon 2017-06-29 12:19:22 +01:00
parent ea4588992d
commit 366c3fc601
1 changed files with 32 additions and 52 deletions
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84
Z80/src/Z80.cpp
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@ -335,22 +335,19 @@ void EightBit::Z80::sbc(uint8_t& f, uint8_t& operand, uint8_t value) {
}
void EightBit::Z80::andr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand &= value;
setFlag(f, HC);
clearFlag(f, CF | NF);
adjustSZPXY<Z80>(f, operand);
adjustSZPXY<Z80>(f, operand &= value);
}
void EightBit::Z80::xorr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand ^= value;
clearFlag(f, HC | CF | NF);
adjustSZPXY<Z80>(f, operand);
adjustSZPXY<Z80>(f, operand ^= value);
}
void EightBit::Z80::orr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand |= value;
clearFlag(f, HC | CF | NF);
adjustSZPXY<Z80>(f, operand);
adjustSZPXY<Z80>(f, operand |= value);
}
void EightBit::Z80::compare(uint8_t& f, uint8_t check, uint8_t value) {
@ -363,41 +360,35 @@ void EightBit::Z80::compare(uint8_t& f, uint8_t check, uint8_t value) {
#pragma region Shift and rotate
uint8_t& EightBit::Z80::rlc(uint8_t& f, uint8_t& operand) {
const auto carry = operand & Bit7;
operand = _rotl8(operand, 1);
setFlag(f, CF, carry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit7);
operand = _rotl8(operand, 1);
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::rrc(uint8_t& f, uint8_t& operand) {
const auto carry = operand & Bit0;
operand = _rotr8(operand, 1);
setFlag(f, CF, carry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit0);
operand = _rotr8(operand, 1);
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::rl(uint8_t& f, uint8_t& operand) {
const auto oldCarry = f & CF;
const auto newCarry = operand & Bit7;
operand <<= 1;
oldCarry ? operand |= Bit0 : operand &= ~Bit0;
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
const auto carry = f & CF;
setFlag(f, CF, operand & Bit7);
operand = (operand << 1) | carry;
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::rr(uint8_t& f, uint8_t& operand) {
const auto oldCarry = f & CF;
const auto newCarry = operand & Bit0;
operand >>= 1;
operand |= oldCarry << 7;
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
const auto carry = f & CF;
setFlag(f, CF, operand & Bit0);
operand = (operand >> 1) | (carry << 7);
adjustXY<Z80>(f, operand);
return operand;
}
@ -405,41 +396,33 @@ uint8_t& EightBit::Z80::rr(uint8_t& f, uint8_t& operand) {
//
uint8_t& EightBit::Z80::sla(uint8_t& f, uint8_t& operand) {
const auto newCarry = operand & Bit7;
operand <<= 1;
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit7);
operand <<= 1;
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::sra(uint8_t& f, uint8_t& operand) {
const auto new7 = operand & Bit7;
const auto newCarry = operand & Bit0;
operand >>= 1;
operand |= new7;
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit0);
operand = (operand >> 1) | operand & Bit7;
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::sll(uint8_t& f, uint8_t& operand) {
const auto newCarry = operand & Bit7;
operand <<= 1;
operand |= 1;
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit7);
operand = (operand << 1) | Bit0;
adjustXY<Z80>(f, operand);
return operand;
}
uint8_t& EightBit::Z80::srl(uint8_t& f, uint8_t& operand) {
const auto newCarry = operand & Bit0;
operand >>= 1;
operand &= ~Bit7; // clear bit 7
setFlag(f, CF, newCarry);
clearFlag(f, NF | HC);
setFlag(f, CF, operand & Bit0);
operand = (operand >> 1) & ~Bit7;
adjustXY<Z80>(f, operand);
setFlag(f, ZF, operand);
return operand;
@ -450,22 +433,20 @@ uint8_t& EightBit::Z80::srl(uint8_t& f, uint8_t& operand) {
#pragma region BIT/SET/RES
uint8_t& EightBit::Z80::bit(uint8_t& f, int n, uint8_t& operand) {
const uint8_t discarded = operand & (1 << n);
setFlag(f, HC);
clearFlag(f, NF);
const uint8_t discarded = operand & (1 << n);
adjustSZXY<Z80>(f, discarded);
clearFlag(f, PF, discarded);
return operand;
}
uint8_t& EightBit::Z80::res(int n, uint8_t& operand) {
operand &= ~(1 << n);
return operand;
return operand &= ~(1 << n);
}
uint8_t& EightBit::Z80::set(int n, uint8_t& operand) {
operand |= (1 << n);
return operand;
return operand |= (1 << n);
}
#pragma endregion BIT/SET/RES
@ -514,22 +495,21 @@ void EightBit::Z80::daa(uint8_t& a, uint8_t& f) {
}
void EightBit::Z80::cpl(uint8_t& a, uint8_t& f) {
a = ~a;
adjustXY<Z80>(f, a);
setFlag(f, HC | NF);
adjustXY<Z80>(f, a = ~a);
}
void EightBit::Z80::scf(uint8_t a, uint8_t& f) {
setFlag(f, CF);
adjustXY<Z80>(f, a);
clearFlag(f, HC | NF);
adjustXY<Z80>(f, a);
}
void EightBit::Z80::ccf(uint8_t a, uint8_t& f) {
clearFlag(f, NF);
const auto carry = f & CF;
setFlag(f, HC, carry);
clearFlag(f, CF, carry);
clearFlag(f, NF);
adjustXY<Z80>(f, a);
}
@ -784,6 +764,11 @@ int EightBit::Z80::execute(uint8_t opcode) {
if (!M1())
throw std::logic_error("M1 cannot be high");
if (!(m_prefixCB && m_displaced)) {
++REFRESH();
M1() = false;
}
const auto& decoded = m_decodedOpcodes[opcode];
auto x = decoded.x;
@ -793,11 +778,6 @@ int EightBit::Z80::execute(uint8_t opcode) {
auto p = decoded.p;
auto q = decoded.q;
if (!(m_prefixCB && m_displaced)) {
++REFRESH();
M1() = false;
}
if (m_prefixCB)
executeCB(x, y, z);
else if (m_prefixED)