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Small tidy up on the block instructions to separate PC changes.

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-06-14 22:33:02 +01:00
parent 1643844eaf
commit 705351d179
1 changed files with 33 additions and 38 deletions
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71
Z80/src/Z80.cpp
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@ -623,22 +623,17 @@ bool EightBit::Z80::cpir() {
cpi();
MEMPTR().word = pc.word;
auto again = (F() & PF) && !(F() & ZF); // See CPI
if (again) {
if (again)
MEMPTR().word--;
pc.word -= 2;
}
return again;
}
bool EightBit::Z80::cpdr() {
cpd();
MEMPTR().word = pc.word;
MEMPTR().word = pc.word - 1;
auto again = (F() & PF) && !(F() & ZF); // See CPD
if (again) {
if (!again) {
MEMPTR().word--;
pc.word -= 2;
} else {
MEMPTR().word -= 2;
}
return again;
}
@ -674,20 +669,16 @@ void EightBit::Z80::ldi() {
bool EightBit::Z80::ldir() {
ldi();
auto again = (F() & PF) != 0;
if (again) { // See LDI
if (again) // See LDI
MEMPTR().word = pc.word - 1;
pc.word -= 2;
}
return again;
}
bool EightBit::Z80::lddr() {
ldd();
auto again = (F() & PF) != 0;
if (F() & PF) { // See LDR
if (again) // See LDR
MEMPTR().word = pc.word - 1;
pc.word -= 2;
}
return again;
}
@ -719,18 +710,12 @@ void EightBit::Z80::ind() {
bool EightBit::Z80::inir() {
ini();
auto again = !(F() & ZF); // See INI
if (again)
pc.word -= 2;
return again;
return !(F() & ZF); // See INI
}
bool EightBit::Z80::indr() {
ind();
auto again = !(F() & ZF); // See IND
if (again)
pc.word -= 2;
return again;
return !(F() & ZF); // See IND
}
#pragma endregion Block input instructions
@ -761,18 +746,12 @@ void EightBit::Z80::outd() {
bool EightBit::Z80::otir() {
outi();
auto again = !(F() & ZF); // See OUTI
if (again)
pc.word -= 2;
return again;
return !(F() & ZF); // See OUTI
}
bool EightBit::Z80::otdr() {
outd();
auto again = !(F() & ZF); // See OUTD
if (again)
pc.word -= 2;
return again;
return !(F() & ZF); // See OUTD
}
#pragma endregion Block output instructions
@ -1105,12 +1084,16 @@ void EightBit::Z80::executeED(int x, int y, int z, int p, int q) {
ldd();
break;
case 6: // LDIR
if (ldir())
if (ldir()) {
pc.word -= 2;
cycles += 5;
}
break;
case 7: // LDDR
if (lddr())
if (lddr()) {
pc.word -= 2;
cycles += 5;
}
break;
}
break;
@ -1123,12 +1106,16 @@ void EightBit::Z80::executeED(int x, int y, int z, int p, int q) {
cpd();
break;
case 6: // CPIR
if (cpir())
if (cpir()) {
pc.word -= 2;
cycles += 5;
}
break;
case 7: // CPDR
if (cpdr())
if (cpdr()) {
pc.word -= 2;
cycles += 5;
}
break;
}
break;
@ -1141,12 +1128,16 @@ void EightBit::Z80::executeED(int x, int y, int z, int p, int q) {
ind();
break;
case 6: // INIR
if (inir())
if (inir()) {
pc.word -= 2;
cycles += 5;
}
break;
case 7: // INDR
if (indr())
if (indr()) {
pc.word -= 2;
cycles += 5;
}
break;
}
break;
@ -1159,12 +1150,16 @@ void EightBit::Z80::executeED(int x, int y, int z, int p, int q) {
outd();
break;
case 6: // OTIR
if (otir())
if (otir()) {
pc.word -= 2;
cycles += 5;
}
break;
case 7: // OTDR
if (otdr())
if (otdr()) {
pc.word -= 2;
cycles += 5;
}
break;
}
break;