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setBitPSW without conditional

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This commit is contained in:
folkert van heusden 2023-03-20 15:11:20 +01:00
parent ce730c6ea1
commit e85e204179
Signed by untrusted user who does not match committer: folkert
GPG key ID: 6B6455EDFEED3BD1
1 changed files with 4 additions and 9 deletions
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13
cpu.cpp
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@ -206,12 +206,8 @@ bool cpu::getPSW_n() const
void cpu::setBitPSW(const int bit, const bool v)
{
const uint16_t mask = 1 << bit;
if (v)
psw |= mask;
else
psw &= ~mask;
psw &= ~(1 << bit);
psw |= v << bit;
}
void cpu::setPSW_c(const bool v)
@ -512,7 +508,7 @@ bool cpu::double_operand_instructions(const uint16_t instr)
bool set_flags = g_dst.addr.has_value() ? g_dst.addr.value() != ADDR_PSW : true;
if (instr & 0x8000) {
if (instr & 0x8000) { // SUB
result = (g_dst.value.value() - g_ssrc.value.value()) & 0xffff;
if (set_flags) {
@ -520,13 +516,12 @@ bool cpu::double_operand_instructions(const uint16_t instr)
setPSW_c(uint16_t(g_dst.value.value()) < uint16_t(g_ssrc.value.value()));
}
}
else {
else { // ADD
uint32_t temp = g_dst.value.value() + g_ssrc.value.value();
result = temp;
if (set_flags) {
setPSW_v((temp ^ g_ssrc.value.value()) & (temp ^ g_dst.value.value()));
setPSW_v(SIGN((~g_ssrc.value.value() ^ g_dst.value.value()) & (g_ssrc.value.value() ^ (temp & 0xffff)), false));
setPSW_c(uint16_t(result) < uint16_t(g_ssrc.value.value()));
}