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34 #include "base/refcnt.hh"
35 #include "cpu/base_dyn_inst.hh"
36 #include "cpu/checker/cpu.hh"
37 #include "cpu/simple_thread.hh"
38 #include "cpu/thread_context.hh"
39 #include "cpu/static_inst.hh"
40 #include "sim/sim_object.hh"
41 #include "sim/stats.hh"
44 #include "arch/vtophys.hh"
48 //The CheckerCPU does alpha only
49 using namespace AlphaISA;
51 template <class DynInstPtr>
53 Checker<DynInstPtr>::verify(DynInstPtr &completed_inst)
57 // Either check this instruction, or add it to a list of
58 // instructions waiting to be checked. Instructions must be
59 // checked in program order, so if a store has committed yet not
60 // completed, there may be some instructions that are waiting
61 // behind it that have completed and must be checked.
62 if (!instList.empty()) {
63 if (youngestSN < completed_inst->seqNum) {
64 DPRINTF(Checker, "Adding instruction [sn:%lli] PC:%#x to list.\n",
65 completed_inst->seqNum, completed_inst->readPC());
66 instList.push_back(completed_inst);
67 youngestSN = completed_inst->seqNum;
70 if (!instList.front()->isCompleted()) {
73 inst = instList.front();
77 if (!completed_inst->isCompleted()) {
78 if (youngestSN < completed_inst->seqNum) {
79 DPRINTF(Checker, "Adding instruction [sn:%lli] PC:%#x to list.\n",
80 completed_inst->seqNum, completed_inst->readPC());
81 instList.push_back(completed_inst);
82 youngestSN = completed_inst->seqNum;
86 if (youngestSN < completed_inst->seqNum) {
87 inst = completed_inst;
88 youngestSN = completed_inst->seqNum;
95 unverifiedInst = inst;
97 // Try to check all instructions that are completed, ending if we
98 // run out of instructions to check or if an instruction is not
101 DPRINTF(Checker, "Processing instruction [sn:%lli] PC:%#x.\n",
102 inst->seqNum, inst->readPC());
103 unverifiedResult.integer = inst->readIntResult();
104 unverifiedReq = inst->req;
105 unverifiedMemData = inst->memData;
108 Fault fault = NoFault;
110 // maintain $r0 semantics
111 thread->setIntReg(ZeroReg, 0);
113 thread->setFloatRegDouble(ZeroReg, 0.0);
114 #endif // TARGET_ALPHA
116 // Check if any recent PC changes match up with anything we
117 // expect to happen. This is mostly to check if traps or
118 // PC-based events have occurred in both the checker and CPU.
120 DPRINTF(Checker, "Changed PC recently to %#x\n",
123 if (newPC == thread->readPC()) {
124 DPRINTF(Checker, "Changed PC matches expected PC\n");
126 warn("%lli: Changed PC does not match expected PC, "
127 "changed: %#x, expected: %#x",
128 curTick, thread->readPC(), newPC);
129 CheckerCPU::handleError();
131 willChangePC = false;
136 DPRINTF(Checker, "Changed NextPC recently to %#x\n",
137 thread->readNextPC());
138 changedNextPC = false;
141 // Try to fetch the instruction
144 #define IFETCH_FLAGS(pc) ((pc) & 1) ? PHYSICAL : 0
146 #define IFETCH_FLAGS(pc) 0
149 uint64_t fetch_PC = thread->readPC() & ~3;
151 // set up memory request for instruction fetch
152 memReq = new Request(inst->threadNumber, fetch_PC,
154 IFETCH_FLAGS(thread->readPC()),
155 fetch_PC, thread->contextId(),
158 bool succeeded = translateInstReq(memReq);
161 if (inst->getFault() == NoFault) {
162 // In this case the instruction was not a dummy
163 // instruction carrying an ITB fault. In the single
164 // threaded case the ITB should still be able to
165 // translate this instruction; in the SMT case it's
166 // possible that its ITB entry was kicked out.
167 warn("%lli: Instruction PC %#x was not found in the ITB!",
168 curTick, thread->readPC());
171 // go to the next instruction
172 thread->setPC(thread->readNextPC());
173 thread->setNextPC(thread->readNextPC() + sizeof(MachInst));
177 // The instruction is carrying an ITB fault. Handle
178 // the fault and see if our results match the CPU on
180 fault = inst->getFault();
184 if (fault == NoFault) {
185 PacketPtr pkt = new Packet(memReq, Packet::ReadReq,
188 pkt->dataStatic(&machInst);
190 icachePort->sendFunctional(pkt);
194 // keep an instruction count
197 // decode the instruction
198 machInst = gtoh(machInst);
199 // Checks that the instruction matches what we expected it to be.
200 // Checks both the machine instruction and the PC.
203 #if THE_ISA == ALPHA_ISA
204 curStaticInst = StaticInst::decode(makeExtMI(machInst,
206 #elif THE_ISA == SPARC_ISA
207 curStaticInst = StaticInst::decode(makeExtMI(machInst,
212 thread->setInst(machInst);
213 #endif // FULL_SYSTEM
215 fault = inst->getFault();
218 // Discard fetch's memReq.
222 // Either the instruction was a fault and we should process the fault,
223 // or we should just go ahead execute the instruction. This assumes
224 // that the instruction is properly marked as a fault.
225 if (fault == NoFault) {
227 thread->funcExeInst++;
229 if (!inst->isUnverifiable())
230 fault = curStaticInst->execute(this, NULL);
232 // Checks to make sure instrution results are correct.
233 validateExecution(inst);
235 if (curStaticInst->isLoad()) {
240 if (fault != NoFault) {
244 newPC = thread->readPC();
245 DPRINTF(Checker, "Fault, PC is now %#x\n", newPC);
248 #if THE_ISA != MIPS_ISA
249 // go to the next instruction
250 thread->setPC(thread->readNextPC());
251 thread->setNextPC(thread->readNextPC() + sizeof(MachInst));
253 // go to the next instruction
254 thread->setPC(thread->readNextPC());
255 thread->setNextPC(thread->readNextNPC());
256 thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst));
262 // @todo: Determine if these should happen only if the
263 // instruction hasn't faulted. In the SimpleCPU case this may
264 // not be true, but in the O3 or Ozone case this may be true.
268 oldpc = thread->readPC();
269 system->pcEventQueue.service(tc);
271 } while (oldpc != thread->readPC());
274 newPC = thread->readPC();
275 DPRINTF(Checker, "PC Event, PC is now %#x\n", newPC);
279 // @todo: Optionally can check all registers. (Or just those
280 // that have been modified).
288 // Continue verifying instructions if there's another completed
289 // instruction waiting to be verified.
290 if (instList.empty()) {
292 } else if (instList.front()->isCompleted()) {
293 inst = instList.front();
294 instList.pop_front();
299 unverifiedInst = NULL;
302 template <class DynInstPtr>
304 Checker<DynInstPtr>::switchOut()
309 template <class DynInstPtr>
311 Checker<DynInstPtr>::takeOverFrom(BaseCPU *oldCPU)
315 template <class DynInstPtr>
317 Checker<DynInstPtr>::validateInst(DynInstPtr &inst)
319 if (inst->readPC() != thread->readPC()) {
320 warn("%lli: PCs do not match! Inst: %#x, checker: %#x",
321 curTick, inst->readPC(), thread->readPC());
323 warn("%lli: Changed PCs recently, may not be an error",
330 MachInst mi = static_cast<MachInst>(inst->staticInst->machInst);
332 if (mi != machInst) {
333 warn("%lli: Binary instructions do not match! Inst: %#x, "
335 curTick, mi, machInst);
340 template <class DynInstPtr>
342 Checker<DynInstPtr>::validateExecution(DynInstPtr &inst)
344 bool result_mismatch = false;
345 if (inst->numDestRegs()) {
346 // @todo: Support more destination registers.
347 if (inst->isUnverifiable()) {
348 // Unverifiable instructions assume they were executed
349 // properly by the CPU. Grab the result from the
350 // instruction and write it to the register.
352 } else if (result.integer != inst->readIntResult()) {
353 result_mismatch = true;
357 if (result_mismatch) {
358 warn("%lli: Instruction results do not match! (Values may not "
359 "actually be integers) Inst: %#x, checker: %#x",
360 curTick, inst->readIntResult(), result.integer);
362 // It's useful to verify load values from memory, but in MP
363 // systems the value obtained at execute may be different than
364 // the value obtained at completion. Similarly DMA can
365 // present the same problem on even UP systems. Thus there is
366 // the option to only warn on loads having a result error.
367 if (inst->isLoad() && warnOnlyOnLoadError) {
374 if (inst->readNextPC() != thread->readNextPC()) {
375 warn("%lli: Instruction next PCs do not match! Inst: %#x, "
377 curTick, inst->readNextPC(), thread->readNextPC());
381 // Checking side effect registers can be difficult if they are not
382 // checked simultaneously with the execution of the instruction.
383 // This is because other valid instructions may have modified
384 // these registers in the meantime, and their values are not
385 // stored within the DynInst.
386 while (!miscRegIdxs.empty()) {
387 int misc_reg_idx = miscRegIdxs.front();
390 if (inst->tcBase()->readMiscRegNoEffect(misc_reg_idx) !=
391 thread->readMiscRegNoEffect(misc_reg_idx)) {
392 warn("%lli: Misc reg idx %i (side effect) does not match! "
393 "Inst: %#x, checker: %#x",
394 curTick, misc_reg_idx,
395 inst->tcBase()->readMiscRegNoEffect(misc_reg_idx),
396 thread->readMiscRegNoEffect(misc_reg_idx));
402 template <class DynInstPtr>
404 Checker<DynInstPtr>::validateState()
406 if (updateThisCycle) {
407 warn("%lli: Instruction PC %#x results didn't match up, copying all "
408 "registers from main CPU", curTick, unverifiedInst->readPC());
409 // Heavy-weight copying of all registers
410 thread->copyArchRegs(unverifiedInst->tcBase());
411 // Also advance the PC. Hopefully no PC-based events happened.
412 #if THE_ISA != MIPS_ISA
413 // go to the next instruction
414 thread->setPC(thread->readNextPC());
415 thread->setNextPC(thread->readNextPC() + sizeof(MachInst));
417 // go to the next instruction
418 thread->setPC(thread->readNextPC());
419 thread->setNextPC(thread->readNextNPC());
420 thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst));
422 updateThisCycle = false;
426 template <class DynInstPtr>
428 Checker<DynInstPtr>::copyResult(DynInstPtr &inst)
430 RegIndex idx = inst->destRegIdx(0);
431 if (idx < TheISA::FP_Base_DepTag) {
432 thread->setIntReg(idx, inst->readIntResult());
433 } else if (idx < TheISA::Fpcr_DepTag) {
434 thread->setFloatRegBits(idx, inst->readIntResult());
436 thread->setMiscRegNoEffect(idx, inst->readIntResult());
440 template <class DynInstPtr>
442 Checker<DynInstPtr>::dumpAndExit(DynInstPtr &inst)
444 cprintf("Error detected, instruction information:\n");
445 cprintf("PC:%#x, nextPC:%#x\n[sn:%lli]\n[tid:%i]\n"
451 inst->isCompleted());
453 CheckerCPU::dumpAndExit();
456 template <class DynInstPtr>
458 Checker<DynInstPtr>::dumpInsts()
462 InstListIt inst_list_it = --(instList.end());
464 cprintf("Inst list size: %i\n", instList.size());
466 while (inst_list_it != instList.end())
468 cprintf("Instruction:%i\n",
471 cprintf("PC:%#x\n[sn:%lli]\n[tid:%i]\n"
473 (*inst_list_it)->readPC(),
474 (*inst_list_it)->seqNum,
475 (*inst_list_it)->threadNumber,
476 (*inst_list_it)->isCompleted());