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Couple of small simplifications.

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-06-13 23:43:21 +01:00
parent 828e081a6e
commit 66d3a5ae29
5 changed files with 17 additions and 17 deletions
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22
Intel8080/inc/Intel8080.h
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@ -83,8 +83,8 @@ namespace EightBit {
return cycles + instruction.count; return cycles + instruction.count;
} }
void adjustSign(uint8_t value) { F().S = ((value & 0x80) != 0); } void adjustSign(uint8_t value) { F().S = ((value & Bit7) != 0); }
void adjustZero(uint8_t value) { F().Z = (value == 0); } void adjustZero(uint8_t value) { F().Z = !value; }
void adjustParity(uint8_t value) { void adjustParity(uint8_t value) {
static const uint8_t lookup[0x10] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 }; static const uint8_t lookup[0x10] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 };
@ -108,12 +108,12 @@ namespace EightBit {
void postIncrement(uint8_t value) { void postIncrement(uint8_t value) {
adjustSZP(value); adjustSZP(value);
F().AC = lowNibble(value) == 0; F().AC = !lowNibble(value);
} }
void postDecrement(uint8_t value) { void postDecrement(uint8_t value) {
adjustSZP(value); adjustSZP(value);
F().AC = lowNibble(value) != 0xf; F().AC = lowNibble(value) != Mask4;
} }
static Instruction INS(instruction_t method, AddressingMode mode, std::string disassembly, int cycles); static Instruction INS(instruction_t method, AddressingMode mode, std::string disassembly, int cycles);
@ -127,11 +127,11 @@ namespace EightBit {
uint16_t subtraction = A() - value; uint16_t subtraction = A() - value;
adjustSZP((uint8_t)subtraction); adjustSZP((uint8_t)subtraction);
adjustAuxiliaryCarrySub(value, subtraction); adjustAuxiliaryCarrySub(value, subtraction);
F().C = subtraction > 0xff; F().C = subtraction & Bit8;
} }
void anda(uint8_t value) { void anda(uint8_t value) {
F().AC = (((A() | value) & 0x8) != 0); F().AC = (((A() | value) & Bit3) != 0);
F().C = false; F().C = false;
adjustSZP(A() &= value); adjustSZP(A() &= value);
} }
@ -151,7 +151,7 @@ namespace EightBit {
sum.word = A() + value + carry; sum.word = A() + value + carry;
adjustAuxiliaryCarryAdd(value, sum.word); adjustAuxiliaryCarryAdd(value, sum.word);
A() = sum.low; A() = sum.low;
F().C = sum.word > 0xff; F().C = sum.word & Bit8;
adjustSZP(A()); adjustSZP(A());
} }
@ -170,7 +170,7 @@ namespace EightBit {
difference.word = A() - value - carry; difference.word = A() - value - carry;
adjustAuxiliaryCarrySub(value, difference.word); adjustAuxiliaryCarrySub(value, difference.word);
A() = difference.low; A() = difference.low;
F().C = difference.word > 0xff; F().C = difference.word & Bit8;
adjustSZP(A()); adjustSZP(A());
} }
@ -592,7 +592,7 @@ namespace EightBit {
// rotate // rotate
void rlc() { void rlc() {
auto carry = A() & 0x80; auto carry = A() & Bit7;
A() <<= 1; A() <<= 1;
A() |= carry >> 7; A() |= carry >> 7;
F().C = carry != 0; F().C = carry != 0;
@ -606,7 +606,7 @@ namespace EightBit {
} }
void ral() { void ral() {
auto carry = A() & 0x80; auto carry = A() & Bit7;
A() <<= 1; A() <<= 1;
A() |= (uint8_t)F().C; A() |= (uint8_t)F().C;
F().C = carry != 0; F().C = carry != 0;
@ -621,7 +621,7 @@ namespace EightBit {
// specials // specials
void cma() { A() ^= 0xff; } void cma() { A() ^= Mask8; }
void stc() { F().C = true; } void stc() { F().C = true; }
void cmc() { F().C = !F().C; } void cmc() { F().C = !F().C; }

2
LR35902/inc/Bus.h
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@ -95,7 +95,7 @@ namespace EightBit {
void loadBootRom(const std::string& path); void loadBootRom(const std::string& path);
bool isBootRom(uint16_t address) const { bool isBootRom(uint16_t address) const {
return (address < m_boot.size()) && (peek(BASE + BOOT_DISABLE) == 0); return (address < m_boot.size()) && !peek(BASE + BOOT_DISABLE);
} }
virtual uint8_t peek(uint16_t address) const; virtual uint8_t peek(uint16_t address) const;

2
LR35902/src/LR35902.cpp
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@ -356,7 +356,7 @@ void EightBit::LR35902::daa() {
uint8_t a = A(); uint8_t a = A();
auto lowAdjust = (F() & HC) | ((A() & 0xf) > 9); auto lowAdjust = (F() & HC) | ((A() & Mask4) > 9);
auto highAdjust = (F() & CF) | (A() > 0x99); auto highAdjust = (F() & CF) | (A() > 0x99);
if (F() & NF) { if (F() & NF) {

4
Z80/src/Z80.cpp
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@ -516,7 +516,7 @@ void EightBit::Z80::neg() {
auto original = A(); auto original = A();
A() = 0; A() = 0;
sub(A(), original); sub(A(), original);
setFlag(PF, original == 0x80); setFlag(PF, original == Bit7);
setFlag(CF, original); setFlag(CF, original);
} }
@ -524,7 +524,7 @@ void EightBit::Z80::daa() {
uint8_t a = A(); uint8_t a = A();
auto lowAdjust = (F() & HC) | ((A() & 0xf) > 9); auto lowAdjust = (F() & HC) | ((A() & Mask4) > 9);
auto highAdjust = (F() & CF) | (A() > 0x99); auto highAdjust = (F() & CF) | (A() > 0x99);
if (F() & NF) { if (F() & NF) {

4
inc/IntelProcessor.h
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@ -22,12 +22,12 @@ namespace EightBit {
bool calculateHalfCarryAdd(uint8_t before, uint8_t value, int calculation) { bool calculateHalfCarryAdd(uint8_t before, uint8_t value, int calculation) {
auto index = buildHalfCarryIndex(before, value, calculation); auto index = buildHalfCarryIndex(before, value, calculation);
return m_halfCarryTableAdd[index & 0x7]; return m_halfCarryTableAdd[index & Mask3];
} }
bool calculateHalfCarrySub(uint8_t before, uint8_t value, int calculation) { bool calculateHalfCarrySub(uint8_t before, uint8_t value, int calculation) {
auto index = buildHalfCarryIndex(before, value, calculation); auto index = buildHalfCarryIndex(before, value, calculation);
return m_halfCarryTableSub[index & 0x7]; return m_halfCarryTableSub[index & Mask3];
} }
void push(uint8_t value); void push(uint8_t value);