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Fixes RTR: the whole top half of the SR should be preserved.

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Specifically, the 68000 Reference Manual says: "The supervisor portion of the status register is unaffected." Clearly when I first read that I misread it as the supervisor _flag_ (rather than _portion_) should be preserved.
This commit is contained in:
Thomas Harte 2019-12-25 19:49:20 -05:00
parent daacd6805e
commit 3cb5684d95
1 changed files with 4 additions and 4 deletions
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8
Processors/68000/Implementation/68000Implementation.hpp
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@ -1854,11 +1854,11 @@ template <class T, bool dtack_is_implicit, bool signal_will_perform> void Proces
RTE and RTR share an implementation.
*/
case Operation::RTE_RTR:
// If this is RTR, patch out the is_supervisor bit.
// If this is RTR, patch out the supervisor half of the status register.
if(decoded_instruction_.full == 0x4e77) {
source_bus_data_[0].full =
(source_bus_data_[0].full & uint32_t(~(1 << 13))) |
uint32_t(is_supervisor_ << 13);
const auto current_status = get_status();
source_bus_data_[0].halves.low.halves.high =
uint8_t(current_status >> 8);
}
set_status(source_bus_data_[0].full);
break;