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Couple of small tidy ups on the LR35902 implementation.

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Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
This commit is contained in:
Adrian Conlon 2017-12-10 21:57:32 +00:00
parent 1edabd79f3
commit a1c753d63e
2 changed files with 13 additions and 15 deletions
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2
LR35902/inc/LR35902.h
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@ -160,8 +160,6 @@ namespace EightBit {
static void subtract(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0); static void subtract(uint8_t& f, uint8_t& operand, uint8_t value, int carry = 0);
// int interrupt(uint8_t value);
void executeCB(int x, int y, int z, int p, int q); void executeCB(int x, int y, int z, int p, int q);
void executeOther(int x, int y, int z, int p, int q); void executeOther(int x, int y, int z, int p, int q);

26
LR35902/src/LR35902.cpp
View File

@ -355,12 +355,12 @@ int EightBit::GameBoy::LR35902::execute(uint8_t opcode) {
const auto p = decoded.p; const auto p = decoded.p;
const auto q = decoded.q; const auto q = decoded.q;
if (m_prefixCB) if (LIKELY(!m_prefixCB))
executeCB(x, y, z, p, q);
else
executeOther(x, y, z, p, q); executeOther(x, y, z, p, q);
else
executeCB(x, y, z, p, q);
if (cycles() == 0) if (UNLIKELY(cycles() == 0))
throw std::logic_error("Unhandled opcode"); throw std::logic_error("Unhandled opcode");
return clockCycles(); return clockCycles();
@ -403,25 +403,25 @@ void EightBit::GameBoy::LR35902::executeCB(int x, int y, int z, int p, int q) {
addCycles(2); addCycles(2);
R(z, a, operand); R(z, a, operand);
adjustZero<LR35902>(f, operand); adjustZero<LR35902>(f, operand);
if (z == 6) if (UNLIKELY(z == 6))
addCycles(2); addCycles(2);
break; break;
} case 1: // BIT y, r[z] } case 1: // BIT y, r[z]
bit(f, y, R(z, a)); bit(f, y, R(z, a));
addCycles(2); addCycles(2);
if (z == 6) if (UNLIKELY(z == 6))
addCycles(2); addCycles(2);
break; break;
case 2: // RES y, r[z] case 2: // RES y, r[z]
R(z, a, res(y, R(z, a))); R(z, a, res(y, R(z, a)));
addCycles(2); addCycles(2);
if (z == 6) if (UNLIKELY(z == 6))
addCycles(2); addCycles(2);
break; break;
case 3: // SET y, r[z] case 3: // SET y, r[z]
R(z, a, set(y, R(z, a))); R(z, a, set(y, R(z, a)));
addCycles(2); addCycles(2);
if (z == 6) if (UNLIKELY(z == 6))
addCycles(2); addCycles(2);
break; break;
default: default:
@ -547,7 +547,7 @@ void EightBit::GameBoy::LR35902::executeOther(int x, int y, int z, int p, int q)
increment(f, operand); increment(f, operand);
R(y, a, operand); R(y, a, operand);
addCycle(); addCycle();
if (y == 6) if (UNLIKELY(y == 6))
addCycles(2); addCycles(2);
break; break;
} case 5: { // 8-bit DEC } case 5: { // 8-bit DEC
@ -555,7 +555,7 @@ void EightBit::GameBoy::LR35902::executeOther(int x, int y, int z, int p, int q)
decrement(f, operand); decrement(f, operand);
R(y, a, operand); R(y, a, operand);
addCycle(); addCycle();
if (y == 6) if (UNLIKELY(y == 6))
addCycles(2); addCycles(2);
break; break;
} case 6: // 8-bit load immediate } case 6: // 8-bit load immediate
@ -598,11 +598,11 @@ void EightBit::GameBoy::LR35902::executeOther(int x, int y, int z, int p, int q)
} }
break; break;
case 1: // 8-bit loading case 1: // 8-bit loading
if (z == 6 && y == 6) { // Exception (replaces LD (HL), (HL)) if (UNLIKELY(z == 6 && y == 6)) { // Exception (replaces LD (HL), (HL))
halt(); halt();
} else { } else {
R(y, a, R(z, a)); R(y, a, R(z, a));
if ((y == 6) || (z == 6)) // M operations if (UNLIKELY((y == 6) || (z == 6))) // M operations
addCycle(); addCycle();
} }
addCycle(); addCycle();
@ -637,7 +637,7 @@ void EightBit::GameBoy::LR35902::executeOther(int x, int y, int z, int p, int q)
UNREACHABLE; UNREACHABLE;
} }
addCycle(); addCycle();
if (z == 6) if (UNLIKELY(z == 6))
addCycle(); addCycle();
break; break;
case 3: case 3: