void lc3_step_one(lc3machine* state)
{
// If the machine is not halted
// Fetch an instruction
// And call lc3_execute
if (state->mem[state->pc] != LC3_TRAP_FULL_HALT) {
u16 instruction = lc3_fetch(state);
lc3_execute(state, instruction);
}
}
/** lc3_step_one
*
* Get the next instrution and execute it if not halted
*
* @param state LC3 simulator
*/
void lc3_step_one(lc3machine* state)
{
// check if machine is running
if (state->halted)
return;
// get the next instruciton
unsigned short instruction = lc3_fetch(state);
// run it
lc3_execute(state, instruction);
}
void lc3_step_one(lc3machine* state)
{
state->halted = 0;
unsigned short instr = lc3_fetch(state); // get instruction returned from fetch
lc3_execute(state, instr); // execute that instruction
}
/** lc3_step
*
* Executes one instruction
*/
void lc3_step(lc3_state& state)
{
// If we are halted then don't step.
if (state.halted) return;
// Tick all plugins
lc3_tick_plugins(state);
// Fetch Instruction
unsigned short data = state.mem[state.pc];
// Test for blackbox (If the line was a JSR statement and it had a blackbox).
bool blackbox_finish = lc3_blackbox_test(state);
// Increment PC
state.pc++;
// Form Instruction
lc3_instr instr = lc3_decode(state, data);
// Execute Instruction
const lc3_state_change change = lc3_execute(state, instr);
// Test for blackbox (If the first line of subroutine had a blackbox).
if (instr.data.opcode == JSR_INSTR || (instr.data.opcode == TRAP_INSTR && state.true_traps))
blackbox_finish = blackbox_finish || lc3_blackbox_test(state);
// Increment executions
state.executions++;
if (state.max_stack_size != 0)
{
// If the change is INTERRUPT END
if (change.changes == LC3_INTERRUPT_END)
{
// After you've scrubbed all of the floors in hyrule (remove all instructions that have been added except the LC3_INTERRUPT change.
lc3_state_change* hmm = &state.undo_stack.back();
while (hmm->changes != LC3_INTERRUPT_BEGIN)
{
state.undo_stack.pop_back();
hmm = &state.undo_stack.back();
}
// Please sire have mercy (Change LC3_INTERRUPT_BEGIN to LC3_INTERRUPT to signal a completed interrupt)
lc3_state_change& lib = state.undo_stack.back();
lib.changes = LC3_INTERRUPT;
}
else
{
// Push Old into state
state.undo_stack.push_back(change);
}
// Never pop if you are in privileged mode.
if (state.privilege && state.max_stack_size < state.undo_stack.size())
state.undo_stack.pop_front();
}
// Tock all plugins
lc3_tock_plugins(state);
if (blackbox_finish)
lc3_finish(state);
// If we hit an error or a halt instruction return. no need to do any breakpoint tests.
if (state.halted) return;
// Breakpoint test
lc3_break_test(state, &change);
if (!state.interrupt_enabled) return;
// Chime in on all observers.
std::list<interrupt_test_func>::iterator i;
for (i = state.interrupt_test.begin(); i != state.interrupt_test.end(); ++i)
{
interrupt_test_func func = *i;
func();
}
// Interrupt?
if (!lc3_interrupt(state)) return;
lc3_state_change interrupt;
interrupt.changes = LC3_INTERRUPT_BEGIN;
interrupt.warnings = state.warnings;
interrupt.executions = state.executions;
if (state.max_stack_size != 0)
state.undo_stack.push_back(interrupt);
// Another breakpoint test
lc3_break_test(state, &interrupt);
}
instr = lc3_decode(state, 0xF100);
BOOST_REQUIRE_EQUAL(instr.trap.opcode, TRAP_INSTR);
BOOST_CHECK_EQUAL(instr.trap.unused, 1);
BOOST_CHECK_EQUAL(instr.trap.vector, 0);
}
BOOST_FIXTURE_TEST_CASE(MalformedInstructionTest, LC3BasicTest)
{
const std::vector<unsigned short> malformed_instructions = {0, 1, 0x1008, 0x4001, 0x4200, 0x5008, 0x8001, 0x903E, 0xC001, 0xC200, 0xF100};
for (const auto& data : malformed_instructions)
{
BOOST_TEST_MESSAGE("data = x" << std::hex << data);
lc3_instr instr = lc3_decode(state, data);
lc3_state_change change = lc3_execute(state, instr);
BOOST_CHECK(state.halted);
BOOST_CHECK_EQUAL(state.warnings, 1);
BOOST_CHECK_EQUAL(state.pc, 0x2FFF);
BOOST_CHECK_EQUAL(change.pc, 0x3000);
BOOST_CHECK(!change.halted);
lc3_init(state, false, false);
}
}
BOOST_FIXTURE_TEST_CASE(MalformedInstructionDisassemble, LC3BasicTest)
{
const std::vector<unsigned short> malformed_instructions = {0, 1, 0x1008, 0x4001, 0x4200, 0x5008, 0x8001, 0x903E, 0xC001, 0xC200, 0xF100};
const std::vector<std::string> answers = {"NOP *", "NOP *", "ADD R0, R0, R0 *", "JSRR R0 *", "JSRR R0 *", "AND R0, R0, R0 *", "RTI *", "NOT R0, R0 *", "JMP R0 *", "JMP R0 *", "TRAP x00 *"};