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Brought the LR35902 a little closer to the Z80

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-08-08 13:32:51 +01:00
parent 99c2e2a719
commit 9fcb349e1f
1 changed files with 26 additions and 17 deletions
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43
LR35902/src/LR35902.cpp
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@ -77,6 +77,8 @@ bool EightBit::LR35902::jrConditionalFlag(uint8_t& f, int flag) {
return jrConditional(!(f & CF));
case 3: // C
return jrConditional(f & CF);
default:
__assume(0);
}
throw std::logic_error("Unhandled JR conditional");
}
@ -91,6 +93,8 @@ bool EightBit::LR35902::jumpConditionalFlag(uint8_t& f, int flag) {
return jumpConditional(!(f & CF));
case 3: // C
return jumpConditional(f & CF);
default:
__assume(0);
}
throw std::logic_error("Unhandled JP conditional");
}
@ -110,6 +114,8 @@ bool EightBit::LR35902::returnConditionalFlag(uint8_t& f, int flag) {
return returnConditional(!(f & CF));
case 3: // C
return returnConditional(f & CF);
default:
__assume(0);
}
throw std::logic_error("Unhandled RET conditional");
}
@ -124,6 +130,8 @@ bool EightBit::LR35902::callConditionalFlag(uint8_t& f, int flag) {
return callConditional(!(f & CF));
case 3: // C
return callConditional(f & CF);
default:
__assume(0);
}
throw std::logic_error("Unhandled CALL conditional");
}
@ -134,15 +142,15 @@ bool EightBit::LR35902::callConditionalFlag(uint8_t& f, int flag) {
void EightBit::LR35902::add(uint8_t& f, register16_t& operand, register16_t value) {
auto before = operand;
MEMPTR() = operand;
auto result = before.word + value.word;
const auto result = MEMPTR().word + value.word;
operand.word = result;
clearFlag(f, NF);
setFlag(f, CF, result & Bit16);
adjustHalfCarryAdd(f, before.high, value.high, operand.high);
adjustHalfCarryAdd(f, MEMPTR().high, value.high, operand.high);
}
#pragma endregion 16-bit arithmetic
@ -164,7 +172,7 @@ void EightBit::LR35902::add(uint8_t& f, uint8_t& operand, uint8_t value, int car
}
void EightBit::LR35902::adc(uint8_t& f, uint8_t& operand, uint8_t value) {
add(operand, value, (f & CF) >> 4);
add(f, operand, value, (f & CF) >> 4);
}
void EightBit::LR35902::subtract(uint8_t& f, uint8_t& operand, uint8_t value, int carry) {
@ -182,26 +190,23 @@ void EightBit::LR35902::subtract(uint8_t& f, uint8_t& operand, uint8_t value, in
}
void EightBit::LR35902::sbc(uint8_t& f, uint8_t& operand, uint8_t value) {
subtract(operand, value, (f & CF) >> 4);
subtract(f, operand, value, (f & CF) >> 4);
}
void EightBit::LR35902::andr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand &= value;
setFlag(f, HC);
clearFlag(f, CF | NF);
adjustZero<LR35902>(f, operand);
adjustZero<LR35902>(f, operand &= value);
}
void EightBit::LR35902::xorr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand ^= value;
clearFlag(f, HC | CF | NF);
adjustZero<LR35902>(f, operand);
adjustZero<LR35902>(f, operand ^= value);
}
void EightBit::LR35902::orr(uint8_t& f, uint8_t& operand, uint8_t value) {
operand |= value;
clearFlag(f, HC | CF | NF);
adjustZero<LR35902>(f, operand);
adjustZero<LR35902>(f, operand |= value);
}
void EightBit::LR35902::compare(uint8_t& f, uint8_t check, uint8_t value) {
@ -320,8 +325,8 @@ void EightBit::LR35902::daa(uint8_t& a, uint8_t& f) {
}
void EightBit::LR35902::cpl(uint8_t& a, uint8_t& f) {
a = ~a;
setFlag(f, HC | NF);
a = ~a;
}
void EightBit::LR35902::scf(uint8_t& a, uint8_t& f) {
@ -378,7 +383,7 @@ void EightBit::LR35902::executeCB(int x, int y, int z, int p, int q) {
auto& a = A();
auto& f = F();
switch (x) {
case 0: { // rot[y] r[z]
case 0: { // rot[y] r[z]
auto operand = R(z, a);
switch (y) {
case 0:
@ -413,7 +418,7 @@ void EightBit::LR35902::executeCB(int x, int y, int z, int p, int q) {
if (z == 6)
cycles += 2;
break;
} case 1: // BIT y, r[z]
} case 1: // BIT y, r[z]
bit(f, y, R(z, a));
cycles += 2;
if (z == 6)
@ -474,7 +479,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
break;
case 1: // 16-bit load immediate/add
switch (q) {
case 0: // LD rp,nn
case 0: // LD rp,nn
Processor::fetchWord(RP(p));
cycles += 3;
break;
@ -532,6 +537,8 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
__assume(0);
}
break;
default:
__assume(0);
}
break;
case 3: // 16-bit INC/DEC
@ -563,7 +570,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
if (y == 6)
cycles += 2;
break;
} case 6: // 8-bit load immediate
} case 6: // 8-bit load immediate
R(y, a, fetchByte()); // LD r,n
cycles += 2;
break;
@ -598,6 +605,8 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
}
cycles++;
break;
default:
__assume(0);
}
break;
case 1: // 8-bit loading
@ -707,7 +716,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
break;
case 2: // JP HL
PC() = HL();
cycles += 1;
cycles++;
break;
case 3: // LD SP,HL
SP() = HL();