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Corrects return address of JSR (An).

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Thomas Harte
2019-04-22 21:11:49 -04:00
parent 6d6046757d
commit 20e774be1e
1 changed files with 11 additions and 3 deletions
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14
Processors/68000/Implementation/68000Implementation.hpp
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@@ -75,7 +75,7 @@ template <class T, bool dtack_is_implicit> void Processor<T, dtack_is_implicit>:
std::cerr << "68000 Abilities exhausted; can't manage instruction " << std::hex << decoded_instruction_ << " from " << (program_counter_.full - 4) << std::endl; std::cerr << "68000 Abilities exhausted; can't manage instruction " << std::hex << decoded_instruction_ << " from " << (program_counter_.full - 4) << std::endl;
return; return;
} else { } else {
// if(0x4f7a == program_counter_.full - 4)return; // if(0x4f7a == program_counter_.full - 4) return;
// std::cout << std::hex << (program_counter_.full - 4) << ": " << std::setw(4) << decoded_instruction_ << '\t'; // std::cout << std::hex << (program_counter_.full - 4) << ": " << std::setw(4) << decoded_instruction_ << '\t';
} }
@@ -1152,11 +1152,19 @@ template <class T, bool dtack_is_implicit> void Processor<T, dtack_is_implicit>:
} }
} break; } break;
case int(MicroOp::Action::PrepareJSR): case int(MicroOp::Action::PrepareJSR): {
const auto mode = (decoded_instruction_ >> 3) & 7;
// Determine the proper resumption address.
switch(mode) {
case 2: destination_bus_data_[0].full = program_counter_.full - 2; break; /* (An) */
default:
destination_bus_data_[0].full = program_counter_.full; /* Everything other than (An) */
break;
}
destination_bus_data_[0].full = program_counter_.full; destination_bus_data_[0].full = program_counter_.full;
address_[7].full -= 4; address_[7].full -= 4;
effective_address_[1].full = address_[7].full; effective_address_[1].full = address_[7].full;
break; } break;
case int(MicroOp::Action::PrepareBSR): case int(MicroOp::Action::PrepareBSR):
destination_bus_data_[0].full = (decoded_instruction_ & 0xff) ? program_counter_.full - 2 : program_counter_.full; destination_bus_data_[0].full = (decoded_instruction_ & 0xff) ? program_counter_.full - 2 : program_counter_.full;