43#include <map>
44
45#include "cpu/o3/inst_queue.hh"
46#include "cpu/o3/mem_dep_unit.hh"
47#include "debug/MemDepUnit.hh"
48#include "params/DerivO3CPU.hh"
49
50template <class MemDepPred, class Impl>
51MemDepUnit<MemDepPred, Impl>::MemDepUnit()
52 : loadBarrier(false), loadBarrierSN(0), storeBarrier(false),
53 storeBarrierSN(0), iqPtr(NULL)
54{
55}
56
57template <class MemDepPred, class Impl>
58MemDepUnit<MemDepPred, Impl>::MemDepUnit(DerivO3CPUParams *params)
59 : _name(params->name + ".memdepunit"),
60 depPred(params->store_set_clear_period, params->SSITSize,
61 params->LFSTSize),
62 loadBarrier(false), loadBarrierSN(0), storeBarrier(false),
63 storeBarrierSN(0), iqPtr(NULL)
64{
65 DPRINTF(MemDepUnit, "Creating MemDepUnit object.\n");
66}
67
68template <class MemDepPred, class Impl>
69MemDepUnit<MemDepPred, Impl>::~MemDepUnit()
70{
71 for (ThreadID tid = 0; tid < Impl::MaxThreads; tid++) {
72
73 ListIt inst_list_it = instList[tid].begin();
74
75 MemDepHashIt hash_it;
76
77 while (!instList[tid].empty()) {
78 hash_it = memDepHash.find((*inst_list_it)->seqNum);
79
80 assert(hash_it != memDepHash.end());
81
82 memDepHash.erase(hash_it);
83
84 instList[tid].erase(inst_list_it++);
85 }
86 }
87
88#ifdef DEBUG
89 assert(MemDepEntry::memdep_count == 0);
90#endif
91}
92
93template <class MemDepPred, class Impl>
94void
95MemDepUnit<MemDepPred, Impl>::init(DerivO3CPUParams *params, ThreadID tid)
96{
97 DPRINTF(MemDepUnit, "Creating MemDepUnit %i object.\n",tid);
98
99 _name = csprintf("%s.memDep%d", params->name, tid);
100 id = tid;
101
102 depPred.init(params->store_set_clear_period, params->SSITSize,
103 params->LFSTSize);
104}
105
106template <class MemDepPred, class Impl>
107void
108MemDepUnit<MemDepPred, Impl>::regStats()
109{
110 insertedLoads
111 .name(name() + ".insertedLoads")
112 .desc("Number of loads inserted to the mem dependence unit.");
113
114 insertedStores
115 .name(name() + ".insertedStores")
116 .desc("Number of stores inserted to the mem dependence unit.");
117
118 conflictingLoads
119 .name(name() + ".conflictingLoads")
120 .desc("Number of conflicting loads.");
121
122 conflictingStores
123 .name(name() + ".conflictingStores")
124 .desc("Number of conflicting stores.");
125}
126
127template <class MemDepPred, class Impl>
128void
129MemDepUnit<MemDepPred, Impl>::drainSanityCheck() const
130{
131 assert(instsToReplay.empty());
132 assert(memDepHash.empty());
133 for (int i = 0; i < Impl::MaxThreads; ++i)
134 assert(instList[i].empty());
135 assert(instsToReplay.empty());
136 assert(memDepHash.empty());
137}
138
139template <class MemDepPred, class Impl>
140void
141MemDepUnit<MemDepPred, Impl>::takeOverFrom()
142{
143 // Be sure to reset all state.
144 loadBarrier = storeBarrier = false;
145 loadBarrierSN = storeBarrierSN = 0;
146 depPred.clear();
147}
148
149template <class MemDepPred, class Impl>
150void
151MemDepUnit<MemDepPred, Impl>::setIQ(InstructionQueue<Impl> *iq_ptr)
152{
153 iqPtr = iq_ptr;
154}
155
156template <class MemDepPred, class Impl>
157void
158MemDepUnit<MemDepPred, Impl>::insert(DynInstPtr &inst)
159{
160 ThreadID tid = inst->threadNumber;
161
162 MemDepEntryPtr inst_entry = new MemDepEntry(inst);
163
164 // Add the MemDepEntry to the hash.
165 memDepHash.insert(
166 std::pair<InstSeqNum, MemDepEntryPtr>(inst->seqNum, inst_entry));
167#ifdef DEBUG
168 MemDepEntry::memdep_insert++;
169#endif
170
171 instList[tid].push_back(inst);
172
173 inst_entry->listIt = --(instList[tid].end());
174
175 // Check any barriers and the dependence predictor for any
176 // producing memrefs/stores.
177 InstSeqNum producing_store;
178 if (inst->isLoad() && loadBarrier) {
179 DPRINTF(MemDepUnit, "Load barrier [sn:%lli] in flight\n",
180 loadBarrierSN);
181 producing_store = loadBarrierSN;
182 } else if (inst->isStore() && storeBarrier) {
183 DPRINTF(MemDepUnit, "Store barrier [sn:%lli] in flight\n",
184 storeBarrierSN);
185 producing_store = storeBarrierSN;
186 } else {
187 producing_store = depPred.checkInst(inst->instAddr());
188 }
189
190 MemDepEntryPtr store_entry = NULL;
191
192 // If there is a producing store, try to find the entry.
193 if (producing_store != 0) {
194 DPRINTF(MemDepUnit, "Searching for producer\n");
195 MemDepHashIt hash_it = memDepHash.find(producing_store);
196
197 if (hash_it != memDepHash.end()) {
198 store_entry = (*hash_it).second;
199 DPRINTF(MemDepUnit, "Proucer found\n");
200 }
201 }
202
203 // If no store entry, then instruction can issue as soon as the registers
204 // are ready.
205 if (!store_entry) {
206 DPRINTF(MemDepUnit, "No dependency for inst PC "
207 "%s [sn:%lli].\n", inst->pcState(), inst->seqNum);
208
209 inst_entry->memDepReady = true;
210
211 if (inst->readyToIssue()) {
212 inst_entry->regsReady = true;
213
214 moveToReady(inst_entry);
215 }
216 } else {
217 // Otherwise make the instruction dependent on the store/barrier.
218 DPRINTF(MemDepUnit, "Adding to dependency list; "
219 "inst PC %s is dependent on [sn:%lli].\n",
220 inst->pcState(), producing_store);
221
222 if (inst->readyToIssue()) {
223 inst_entry->regsReady = true;
224 }
225
226 // Clear the bit saying this instruction can issue.
227 inst->clearCanIssue();
228
229 // Add this instruction to the list of dependents.
230 store_entry->dependInsts.push_back(inst_entry);
231
232 if (inst->isLoad()) {
233 ++conflictingLoads;
234 } else {
235 ++conflictingStores;
236 }
237 }
238
239 if (inst->isStore()) {
240 DPRINTF(MemDepUnit, "Inserting store PC %s [sn:%lli].\n",
241 inst->pcState(), inst->seqNum);
242
243 depPred.insertStore(inst->instAddr(), inst->seqNum, inst->threadNumber);
244
245 ++insertedStores;
246 } else if (inst->isLoad()) {
247 ++insertedLoads;
248 } else {
249 panic("Unknown type! (most likely a barrier).");
250 }
251}
252
253template <class MemDepPred, class Impl>
254void
255MemDepUnit<MemDepPred, Impl>::insertNonSpec(DynInstPtr &inst)
256{
257 ThreadID tid = inst->threadNumber;
258
259 MemDepEntryPtr inst_entry = new MemDepEntry(inst);
260
261 // Insert the MemDepEntry into the hash.
262 memDepHash.insert(
263 std::pair<InstSeqNum, MemDepEntryPtr>(inst->seqNum, inst_entry));
264#ifdef DEBUG
265 MemDepEntry::memdep_insert++;
266#endif
267
268 // Add the instruction to the list.
269 instList[tid].push_back(inst);
270
271 inst_entry->listIt = --(instList[tid].end());
272
273 // Might want to turn this part into an inline function or something.
274 // It's shared between both insert functions.
275 if (inst->isStore()) {
276 DPRINTF(MemDepUnit, "Inserting store PC %s [sn:%lli].\n",
277 inst->pcState(), inst->seqNum);
278
279 depPred.insertStore(inst->instAddr(), inst->seqNum, inst->threadNumber);
280
281 ++insertedStores;
282 } else if (inst->isLoad()) {
283 ++insertedLoads;
284 } else {
285 panic("Unknown type! (most likely a barrier).");
286 }
287}
288
289template <class MemDepPred, class Impl>
290void
291MemDepUnit<MemDepPred, Impl>::insertBarrier(DynInstPtr &barr_inst)
292{
293 InstSeqNum barr_sn = barr_inst->seqNum;
294 // Memory barriers block loads and stores, write barriers only stores.
295 if (barr_inst->isMemBarrier()) {
296 loadBarrier = true;
297 loadBarrierSN = barr_sn;
298 storeBarrier = true;
299 storeBarrierSN = barr_sn;
300 DPRINTF(MemDepUnit, "Inserted a memory barrier %s SN:%lli\n",
301 barr_inst->pcState(),barr_sn);
302 } else if (barr_inst->isWriteBarrier()) {
303 storeBarrier = true;
304 storeBarrierSN = barr_sn;
305 DPRINTF(MemDepUnit, "Inserted a write barrier\n");
306 }
307
308 ThreadID tid = barr_inst->threadNumber;
309
310 MemDepEntryPtr inst_entry = new MemDepEntry(barr_inst);
311
312 // Add the MemDepEntry to the hash.
313 memDepHash.insert(
314 std::pair<InstSeqNum, MemDepEntryPtr>(barr_sn, inst_entry));
315#ifdef DEBUG
316 MemDepEntry::memdep_insert++;
317#endif
318
319 // Add the instruction to the instruction list.
320 instList[tid].push_back(barr_inst);
321
322 inst_entry->listIt = --(instList[tid].end());
323}
324
325template <class MemDepPred, class Impl>
326void
327MemDepUnit<MemDepPred, Impl>::regsReady(DynInstPtr &inst)
328{
329 DPRINTF(MemDepUnit, "Marking registers as ready for "
330 "instruction PC %s [sn:%lli].\n",
331 inst->pcState(), inst->seqNum);
332
333 MemDepEntryPtr inst_entry = findInHash(inst);
334
335 inst_entry->regsReady = true;
336
337 if (inst_entry->memDepReady) {
338 DPRINTF(MemDepUnit, "Instruction has its memory "
339 "dependencies resolved, adding it to the ready list.\n");
340
341 moveToReady(inst_entry);
342 } else {
343 DPRINTF(MemDepUnit, "Instruction still waiting on "
344 "memory dependency.\n");
345 }
346}
347
348template <class MemDepPred, class Impl>
349void
350MemDepUnit<MemDepPred, Impl>::nonSpecInstReady(DynInstPtr &inst)
351{
352 DPRINTF(MemDepUnit, "Marking non speculative "
353 "instruction PC %s as ready [sn:%lli].\n",
354 inst->pcState(), inst->seqNum);
355
356 MemDepEntryPtr inst_entry = findInHash(inst);
357
358 moveToReady(inst_entry);
359}
360
361template <class MemDepPred, class Impl>
362void
363MemDepUnit<MemDepPred, Impl>::reschedule(DynInstPtr &inst)
364{
365 instsToReplay.push_back(inst);
366}
367
368template <class MemDepPred, class Impl>
369void
370MemDepUnit<MemDepPred, Impl>::replay(DynInstPtr &inst)
371{
372 DynInstPtr temp_inst;
373
374 // For now this replay function replays all waiting memory ops.
375 while (!instsToReplay.empty()) {
376 temp_inst = instsToReplay.front();
377
378 MemDepEntryPtr inst_entry = findInHash(temp_inst);
379
380 DPRINTF(MemDepUnit, "Replaying mem instruction PC %s [sn:%lli].\n",
381 temp_inst->pcState(), temp_inst->seqNum);
382
383 moveToReady(inst_entry);
384
385 instsToReplay.pop_front();
386 }
387}
388
389template <class MemDepPred, class Impl>
390void
391MemDepUnit<MemDepPred, Impl>::completed(DynInstPtr &inst)
392{
393 DPRINTF(MemDepUnit, "Completed mem instruction PC %s [sn:%lli].\n",
394 inst->pcState(), inst->seqNum);
395
396 ThreadID tid = inst->threadNumber;
397
398 // Remove the instruction from the hash and the list.
399 MemDepHashIt hash_it = memDepHash.find(inst->seqNum);
400
401 assert(hash_it != memDepHash.end());
402
403 instList[tid].erase((*hash_it).second->listIt);
404
405 (*hash_it).second = NULL;
406
407 memDepHash.erase(hash_it);
408#ifdef DEBUG
409 MemDepEntry::memdep_erase++;
410#endif
411}
412
413template <class MemDepPred, class Impl>
414void
415MemDepUnit<MemDepPred, Impl>::completeBarrier(DynInstPtr &inst)
416{
417 wakeDependents(inst);
418 completed(inst);
419
420 InstSeqNum barr_sn = inst->seqNum;
421 DPRINTF(MemDepUnit, "barrier completed: %s SN:%lli\n", inst->pcState(),
422 inst->seqNum);
423 if (inst->isMemBarrier()) {
424 if (loadBarrierSN == barr_sn)
425 loadBarrier = false;
426 if (storeBarrierSN == barr_sn)
427 storeBarrier = false;
428 } else if (inst->isWriteBarrier()) {
429 if (storeBarrierSN == barr_sn)
430 storeBarrier = false;
431 }
432}
433
434template <class MemDepPred, class Impl>
435void
436MemDepUnit<MemDepPred, Impl>::wakeDependents(DynInstPtr &inst)
437{
438 // Only stores and barriers have dependents.
439 if (!inst->isStore() && !inst->isMemBarrier() && !inst->isWriteBarrier()) {
440 return;
441 }
442
443 MemDepEntryPtr inst_entry = findInHash(inst);
444
445 for (int i = 0; i < inst_entry->dependInsts.size(); ++i ) {
446 MemDepEntryPtr woken_inst = inst_entry->dependInsts[i];
447
448 if (!woken_inst->inst) {
449 // Potentially removed mem dep entries could be on this list
450 continue;
451 }
452
453 DPRINTF(MemDepUnit, "Waking up a dependent inst, "
454 "[sn:%lli].\n",
455 woken_inst->inst->seqNum);
456
457 if (woken_inst->regsReady && !woken_inst->squashed) {
458 moveToReady(woken_inst);
459 } else {
460 woken_inst->memDepReady = true;
461 }
462 }
463
464 inst_entry->dependInsts.clear();
465}
466
467template <class MemDepPred, class Impl>
468void
469MemDepUnit<MemDepPred, Impl>::squash(const InstSeqNum &squashed_num,
470 ThreadID tid)
471{
472 if (!instsToReplay.empty()) {
473 ListIt replay_it = instsToReplay.begin();
474 while (replay_it != instsToReplay.end()) {
475 if ((*replay_it)->threadNumber == tid &&
476 (*replay_it)->seqNum > squashed_num) {
477 instsToReplay.erase(replay_it++);
478 } else {
479 ++replay_it;
480 }
481 }
482 }
483
484 ListIt squash_it = instList[tid].end();
485 --squash_it;
486
487 MemDepHashIt hash_it;
488
489 while (!instList[tid].empty() &&
490 (*squash_it)->seqNum > squashed_num) {
491
492 DPRINTF(MemDepUnit, "Squashing inst [sn:%lli]\n",
493 (*squash_it)->seqNum);
494
495 if ((*squash_it)->seqNum == loadBarrierSN)
496 loadBarrier = false;
497
498 if ((*squash_it)->seqNum == storeBarrierSN)
499 storeBarrier = false;
500
501 hash_it = memDepHash.find((*squash_it)->seqNum);
502
503 assert(hash_it != memDepHash.end());
504
505 (*hash_it).second->squashed = true;
506
507 (*hash_it).second = NULL;
508
509 memDepHash.erase(hash_it);
510#ifdef DEBUG
511 MemDepEntry::memdep_erase++;
512#endif
513
514 instList[tid].erase(squash_it--);
515 }
516
517 // Tell the dependency predictor to squash as well.
518 depPred.squash(squashed_num, tid);
519}
520
521template <class MemDepPred, class Impl>
522void
523MemDepUnit<MemDepPred, Impl>::violation(DynInstPtr &store_inst,
524 DynInstPtr &violating_load)
525{
526 DPRINTF(MemDepUnit, "Passing violating PCs to store sets,"
527 " load: %#x, store: %#x\n", violating_load->instAddr(),
528 store_inst->instAddr());
529 // Tell the memory dependence unit of the violation.
530 depPred.violation(store_inst->instAddr(), violating_load->instAddr());
531}
532
533template <class MemDepPred, class Impl>
534void
535MemDepUnit<MemDepPred, Impl>::issue(DynInstPtr &inst)
536{
537 DPRINTF(MemDepUnit, "Issuing instruction PC %#x [sn:%lli].\n",
538 inst->instAddr(), inst->seqNum);
539
540 depPred.issued(inst->instAddr(), inst->seqNum, inst->isStore());
541}
542
543template <class MemDepPred, class Impl>
544inline typename MemDepUnit<MemDepPred,Impl>::MemDepEntryPtr &
545MemDepUnit<MemDepPred, Impl>::findInHash(const DynInstPtr &inst)
546{
547 MemDepHashIt hash_it = memDepHash.find(inst->seqNum);
548
549 assert(hash_it != memDepHash.end());
550
551 return (*hash_it).second;
552}
553
554template <class MemDepPred, class Impl>
555inline void
556MemDepUnit<MemDepPred, Impl>::moveToReady(MemDepEntryPtr &woken_inst_entry)
557{
558 DPRINTF(MemDepUnit, "Adding instruction [sn:%lli] "
559 "to the ready list.\n", woken_inst_entry->inst->seqNum);
560
561 assert(!woken_inst_entry->squashed);
562
563 iqPtr->addReadyMemInst(woken_inst_entry->inst);
564}
565
566
567template <class MemDepPred, class Impl>
568void
569MemDepUnit<MemDepPred, Impl>::dumpLists()
570{
571 for (ThreadID tid = 0; tid < Impl::MaxThreads; tid++) {
572 cprintf("Instruction list %i size: %i\n",
573 tid, instList[tid].size());
574
575 ListIt inst_list_it = instList[tid].begin();
576 int num = 0;
577
578 while (inst_list_it != instList[tid].end()) {
579 cprintf("Instruction:%i\nPC: %s\n[sn:%i]\n[tid:%i]\nIssued:%i\n"
580 "Squashed:%i\n\n",
581 num, (*inst_list_it)->pcState(),
582 (*inst_list_it)->seqNum,
583 (*inst_list_it)->threadNumber,
584 (*inst_list_it)->isIssued(),
585 (*inst_list_it)->isSquashed());
586 inst_list_it++;
587 ++num;
588 }
589 }
590
591 cprintf("Memory dependence hash size: %i\n", memDepHash.size());
592
593#ifdef DEBUG
594 cprintf("Memory dependence entries: %i\n", MemDepEntry::memdep_count);
595#endif
596}
| 46#include <map>
47
48#include "cpu/o3/inst_queue.hh"
49#include "cpu/o3/mem_dep_unit.hh"
50#include "debug/MemDepUnit.hh"
51#include "params/DerivO3CPU.hh"
52
53template <class MemDepPred, class Impl>
54MemDepUnit<MemDepPred, Impl>::MemDepUnit()
55 : loadBarrier(false), loadBarrierSN(0), storeBarrier(false),
56 storeBarrierSN(0), iqPtr(NULL)
57{
58}
59
60template <class MemDepPred, class Impl>
61MemDepUnit<MemDepPred, Impl>::MemDepUnit(DerivO3CPUParams *params)
62 : _name(params->name + ".memdepunit"),
63 depPred(params->store_set_clear_period, params->SSITSize,
64 params->LFSTSize),
65 loadBarrier(false), loadBarrierSN(0), storeBarrier(false),
66 storeBarrierSN(0), iqPtr(NULL)
67{
68 DPRINTF(MemDepUnit, "Creating MemDepUnit object.\n");
69}
70
71template <class MemDepPred, class Impl>
72MemDepUnit<MemDepPred, Impl>::~MemDepUnit()
73{
74 for (ThreadID tid = 0; tid < Impl::MaxThreads; tid++) {
75
76 ListIt inst_list_it = instList[tid].begin();
77
78 MemDepHashIt hash_it;
79
80 while (!instList[tid].empty()) {
81 hash_it = memDepHash.find((*inst_list_it)->seqNum);
82
83 assert(hash_it != memDepHash.end());
84
85 memDepHash.erase(hash_it);
86
87 instList[tid].erase(inst_list_it++);
88 }
89 }
90
91#ifdef DEBUG
92 assert(MemDepEntry::memdep_count == 0);
93#endif
94}
95
96template <class MemDepPred, class Impl>
97void
98MemDepUnit<MemDepPred, Impl>::init(DerivO3CPUParams *params, ThreadID tid)
99{
100 DPRINTF(MemDepUnit, "Creating MemDepUnit %i object.\n",tid);
101
102 _name = csprintf("%s.memDep%d", params->name, tid);
103 id = tid;
104
105 depPred.init(params->store_set_clear_period, params->SSITSize,
106 params->LFSTSize);
107}
108
109template <class MemDepPred, class Impl>
110void
111MemDepUnit<MemDepPred, Impl>::regStats()
112{
113 insertedLoads
114 .name(name() + ".insertedLoads")
115 .desc("Number of loads inserted to the mem dependence unit.");
116
117 insertedStores
118 .name(name() + ".insertedStores")
119 .desc("Number of stores inserted to the mem dependence unit.");
120
121 conflictingLoads
122 .name(name() + ".conflictingLoads")
123 .desc("Number of conflicting loads.");
124
125 conflictingStores
126 .name(name() + ".conflictingStores")
127 .desc("Number of conflicting stores.");
128}
129
130template <class MemDepPred, class Impl>
131void
132MemDepUnit<MemDepPred, Impl>::drainSanityCheck() const
133{
134 assert(instsToReplay.empty());
135 assert(memDepHash.empty());
136 for (int i = 0; i < Impl::MaxThreads; ++i)
137 assert(instList[i].empty());
138 assert(instsToReplay.empty());
139 assert(memDepHash.empty());
140}
141
142template <class MemDepPred, class Impl>
143void
144MemDepUnit<MemDepPred, Impl>::takeOverFrom()
145{
146 // Be sure to reset all state.
147 loadBarrier = storeBarrier = false;
148 loadBarrierSN = storeBarrierSN = 0;
149 depPred.clear();
150}
151
152template <class MemDepPred, class Impl>
153void
154MemDepUnit<MemDepPred, Impl>::setIQ(InstructionQueue<Impl> *iq_ptr)
155{
156 iqPtr = iq_ptr;
157}
158
159template <class MemDepPred, class Impl>
160void
161MemDepUnit<MemDepPred, Impl>::insert(DynInstPtr &inst)
162{
163 ThreadID tid = inst->threadNumber;
164
165 MemDepEntryPtr inst_entry = new MemDepEntry(inst);
166
167 // Add the MemDepEntry to the hash.
168 memDepHash.insert(
169 std::pair<InstSeqNum, MemDepEntryPtr>(inst->seqNum, inst_entry));
170#ifdef DEBUG
171 MemDepEntry::memdep_insert++;
172#endif
173
174 instList[tid].push_back(inst);
175
176 inst_entry->listIt = --(instList[tid].end());
177
178 // Check any barriers and the dependence predictor for any
179 // producing memrefs/stores.
180 InstSeqNum producing_store;
181 if (inst->isLoad() && loadBarrier) {
182 DPRINTF(MemDepUnit, "Load barrier [sn:%lli] in flight\n",
183 loadBarrierSN);
184 producing_store = loadBarrierSN;
185 } else if (inst->isStore() && storeBarrier) {
186 DPRINTF(MemDepUnit, "Store barrier [sn:%lli] in flight\n",
187 storeBarrierSN);
188 producing_store = storeBarrierSN;
189 } else {
190 producing_store = depPred.checkInst(inst->instAddr());
191 }
192
193 MemDepEntryPtr store_entry = NULL;
194
195 // If there is a producing store, try to find the entry.
196 if (producing_store != 0) {
197 DPRINTF(MemDepUnit, "Searching for producer\n");
198 MemDepHashIt hash_it = memDepHash.find(producing_store);
199
200 if (hash_it != memDepHash.end()) {
201 store_entry = (*hash_it).second;
202 DPRINTF(MemDepUnit, "Proucer found\n");
203 }
204 }
205
206 // If no store entry, then instruction can issue as soon as the registers
207 // are ready.
208 if (!store_entry) {
209 DPRINTF(MemDepUnit, "No dependency for inst PC "
210 "%s [sn:%lli].\n", inst->pcState(), inst->seqNum);
211
212 inst_entry->memDepReady = true;
213
214 if (inst->readyToIssue()) {
215 inst_entry->regsReady = true;
216
217 moveToReady(inst_entry);
218 }
219 } else {
220 // Otherwise make the instruction dependent on the store/barrier.
221 DPRINTF(MemDepUnit, "Adding to dependency list; "
222 "inst PC %s is dependent on [sn:%lli].\n",
223 inst->pcState(), producing_store);
224
225 if (inst->readyToIssue()) {
226 inst_entry->regsReady = true;
227 }
228
229 // Clear the bit saying this instruction can issue.
230 inst->clearCanIssue();
231
232 // Add this instruction to the list of dependents.
233 store_entry->dependInsts.push_back(inst_entry);
234
235 if (inst->isLoad()) {
236 ++conflictingLoads;
237 } else {
238 ++conflictingStores;
239 }
240 }
241
242 if (inst->isStore()) {
243 DPRINTF(MemDepUnit, "Inserting store PC %s [sn:%lli].\n",
244 inst->pcState(), inst->seqNum);
245
246 depPred.insertStore(inst->instAddr(), inst->seqNum, inst->threadNumber);
247
248 ++insertedStores;
249 } else if (inst->isLoad()) {
250 ++insertedLoads;
251 } else {
252 panic("Unknown type! (most likely a barrier).");
253 }
254}
255
256template <class MemDepPred, class Impl>
257void
258MemDepUnit<MemDepPred, Impl>::insertNonSpec(DynInstPtr &inst)
259{
260 ThreadID tid = inst->threadNumber;
261
262 MemDepEntryPtr inst_entry = new MemDepEntry(inst);
263
264 // Insert the MemDepEntry into the hash.
265 memDepHash.insert(
266 std::pair<InstSeqNum, MemDepEntryPtr>(inst->seqNum, inst_entry));
267#ifdef DEBUG
268 MemDepEntry::memdep_insert++;
269#endif
270
271 // Add the instruction to the list.
272 instList[tid].push_back(inst);
273
274 inst_entry->listIt = --(instList[tid].end());
275
276 // Might want to turn this part into an inline function or something.
277 // It's shared between both insert functions.
278 if (inst->isStore()) {
279 DPRINTF(MemDepUnit, "Inserting store PC %s [sn:%lli].\n",
280 inst->pcState(), inst->seqNum);
281
282 depPred.insertStore(inst->instAddr(), inst->seqNum, inst->threadNumber);
283
284 ++insertedStores;
285 } else if (inst->isLoad()) {
286 ++insertedLoads;
287 } else {
288 panic("Unknown type! (most likely a barrier).");
289 }
290}
291
292template <class MemDepPred, class Impl>
293void
294MemDepUnit<MemDepPred, Impl>::insertBarrier(DynInstPtr &barr_inst)
295{
296 InstSeqNum barr_sn = barr_inst->seqNum;
297 // Memory barriers block loads and stores, write barriers only stores.
298 if (barr_inst->isMemBarrier()) {
299 loadBarrier = true;
300 loadBarrierSN = barr_sn;
301 storeBarrier = true;
302 storeBarrierSN = barr_sn;
303 DPRINTF(MemDepUnit, "Inserted a memory barrier %s SN:%lli\n",
304 barr_inst->pcState(),barr_sn);
305 } else if (barr_inst->isWriteBarrier()) {
306 storeBarrier = true;
307 storeBarrierSN = barr_sn;
308 DPRINTF(MemDepUnit, "Inserted a write barrier\n");
309 }
310
311 ThreadID tid = barr_inst->threadNumber;
312
313 MemDepEntryPtr inst_entry = new MemDepEntry(barr_inst);
314
315 // Add the MemDepEntry to the hash.
316 memDepHash.insert(
317 std::pair<InstSeqNum, MemDepEntryPtr>(barr_sn, inst_entry));
318#ifdef DEBUG
319 MemDepEntry::memdep_insert++;
320#endif
321
322 // Add the instruction to the instruction list.
323 instList[tid].push_back(barr_inst);
324
325 inst_entry->listIt = --(instList[tid].end());
326}
327
328template <class MemDepPred, class Impl>
329void
330MemDepUnit<MemDepPred, Impl>::regsReady(DynInstPtr &inst)
331{
332 DPRINTF(MemDepUnit, "Marking registers as ready for "
333 "instruction PC %s [sn:%lli].\n",
334 inst->pcState(), inst->seqNum);
335
336 MemDepEntryPtr inst_entry = findInHash(inst);
337
338 inst_entry->regsReady = true;
339
340 if (inst_entry->memDepReady) {
341 DPRINTF(MemDepUnit, "Instruction has its memory "
342 "dependencies resolved, adding it to the ready list.\n");
343
344 moveToReady(inst_entry);
345 } else {
346 DPRINTF(MemDepUnit, "Instruction still waiting on "
347 "memory dependency.\n");
348 }
349}
350
351template <class MemDepPred, class Impl>
352void
353MemDepUnit<MemDepPred, Impl>::nonSpecInstReady(DynInstPtr &inst)
354{
355 DPRINTF(MemDepUnit, "Marking non speculative "
356 "instruction PC %s as ready [sn:%lli].\n",
357 inst->pcState(), inst->seqNum);
358
359 MemDepEntryPtr inst_entry = findInHash(inst);
360
361 moveToReady(inst_entry);
362}
363
364template <class MemDepPred, class Impl>
365void
366MemDepUnit<MemDepPred, Impl>::reschedule(DynInstPtr &inst)
367{
368 instsToReplay.push_back(inst);
369}
370
371template <class MemDepPred, class Impl>
372void
373MemDepUnit<MemDepPred, Impl>::replay(DynInstPtr &inst)
374{
375 DynInstPtr temp_inst;
376
377 // For now this replay function replays all waiting memory ops.
378 while (!instsToReplay.empty()) {
379 temp_inst = instsToReplay.front();
380
381 MemDepEntryPtr inst_entry = findInHash(temp_inst);
382
383 DPRINTF(MemDepUnit, "Replaying mem instruction PC %s [sn:%lli].\n",
384 temp_inst->pcState(), temp_inst->seqNum);
385
386 moveToReady(inst_entry);
387
388 instsToReplay.pop_front();
389 }
390}
391
392template <class MemDepPred, class Impl>
393void
394MemDepUnit<MemDepPred, Impl>::completed(DynInstPtr &inst)
395{
396 DPRINTF(MemDepUnit, "Completed mem instruction PC %s [sn:%lli].\n",
397 inst->pcState(), inst->seqNum);
398
399 ThreadID tid = inst->threadNumber;
400
401 // Remove the instruction from the hash and the list.
402 MemDepHashIt hash_it = memDepHash.find(inst->seqNum);
403
404 assert(hash_it != memDepHash.end());
405
406 instList[tid].erase((*hash_it).second->listIt);
407
408 (*hash_it).second = NULL;
409
410 memDepHash.erase(hash_it);
411#ifdef DEBUG
412 MemDepEntry::memdep_erase++;
413#endif
414}
415
416template <class MemDepPred, class Impl>
417void
418MemDepUnit<MemDepPred, Impl>::completeBarrier(DynInstPtr &inst)
419{
420 wakeDependents(inst);
421 completed(inst);
422
423 InstSeqNum barr_sn = inst->seqNum;
424 DPRINTF(MemDepUnit, "barrier completed: %s SN:%lli\n", inst->pcState(),
425 inst->seqNum);
426 if (inst->isMemBarrier()) {
427 if (loadBarrierSN == barr_sn)
428 loadBarrier = false;
429 if (storeBarrierSN == barr_sn)
430 storeBarrier = false;
431 } else if (inst->isWriteBarrier()) {
432 if (storeBarrierSN == barr_sn)
433 storeBarrier = false;
434 }
435}
436
437template <class MemDepPred, class Impl>
438void
439MemDepUnit<MemDepPred, Impl>::wakeDependents(DynInstPtr &inst)
440{
441 // Only stores and barriers have dependents.
442 if (!inst->isStore() && !inst->isMemBarrier() && !inst->isWriteBarrier()) {
443 return;
444 }
445
446 MemDepEntryPtr inst_entry = findInHash(inst);
447
448 for (int i = 0; i < inst_entry->dependInsts.size(); ++i ) {
449 MemDepEntryPtr woken_inst = inst_entry->dependInsts[i];
450
451 if (!woken_inst->inst) {
452 // Potentially removed mem dep entries could be on this list
453 continue;
454 }
455
456 DPRINTF(MemDepUnit, "Waking up a dependent inst, "
457 "[sn:%lli].\n",
458 woken_inst->inst->seqNum);
459
460 if (woken_inst->regsReady && !woken_inst->squashed) {
461 moveToReady(woken_inst);
462 } else {
463 woken_inst->memDepReady = true;
464 }
465 }
466
467 inst_entry->dependInsts.clear();
468}
469
470template <class MemDepPred, class Impl>
471void
472MemDepUnit<MemDepPred, Impl>::squash(const InstSeqNum &squashed_num,
473 ThreadID tid)
474{
475 if (!instsToReplay.empty()) {
476 ListIt replay_it = instsToReplay.begin();
477 while (replay_it != instsToReplay.end()) {
478 if ((*replay_it)->threadNumber == tid &&
479 (*replay_it)->seqNum > squashed_num) {
480 instsToReplay.erase(replay_it++);
481 } else {
482 ++replay_it;
483 }
484 }
485 }
486
487 ListIt squash_it = instList[tid].end();
488 --squash_it;
489
490 MemDepHashIt hash_it;
491
492 while (!instList[tid].empty() &&
493 (*squash_it)->seqNum > squashed_num) {
494
495 DPRINTF(MemDepUnit, "Squashing inst [sn:%lli]\n",
496 (*squash_it)->seqNum);
497
498 if ((*squash_it)->seqNum == loadBarrierSN)
499 loadBarrier = false;
500
501 if ((*squash_it)->seqNum == storeBarrierSN)
502 storeBarrier = false;
503
504 hash_it = memDepHash.find((*squash_it)->seqNum);
505
506 assert(hash_it != memDepHash.end());
507
508 (*hash_it).second->squashed = true;
509
510 (*hash_it).second = NULL;
511
512 memDepHash.erase(hash_it);
513#ifdef DEBUG
514 MemDepEntry::memdep_erase++;
515#endif
516
517 instList[tid].erase(squash_it--);
518 }
519
520 // Tell the dependency predictor to squash as well.
521 depPred.squash(squashed_num, tid);
522}
523
524template <class MemDepPred, class Impl>
525void
526MemDepUnit<MemDepPred, Impl>::violation(DynInstPtr &store_inst,
527 DynInstPtr &violating_load)
528{
529 DPRINTF(MemDepUnit, "Passing violating PCs to store sets,"
530 " load: %#x, store: %#x\n", violating_load->instAddr(),
531 store_inst->instAddr());
532 // Tell the memory dependence unit of the violation.
533 depPred.violation(store_inst->instAddr(), violating_load->instAddr());
534}
535
536template <class MemDepPred, class Impl>
537void
538MemDepUnit<MemDepPred, Impl>::issue(DynInstPtr &inst)
539{
540 DPRINTF(MemDepUnit, "Issuing instruction PC %#x [sn:%lli].\n",
541 inst->instAddr(), inst->seqNum);
542
543 depPred.issued(inst->instAddr(), inst->seqNum, inst->isStore());
544}
545
546template <class MemDepPred, class Impl>
547inline typename MemDepUnit<MemDepPred,Impl>::MemDepEntryPtr &
548MemDepUnit<MemDepPred, Impl>::findInHash(const DynInstPtr &inst)
549{
550 MemDepHashIt hash_it = memDepHash.find(inst->seqNum);
551
552 assert(hash_it != memDepHash.end());
553
554 return (*hash_it).second;
555}
556
557template <class MemDepPred, class Impl>
558inline void
559MemDepUnit<MemDepPred, Impl>::moveToReady(MemDepEntryPtr &woken_inst_entry)
560{
561 DPRINTF(MemDepUnit, "Adding instruction [sn:%lli] "
562 "to the ready list.\n", woken_inst_entry->inst->seqNum);
563
564 assert(!woken_inst_entry->squashed);
565
566 iqPtr->addReadyMemInst(woken_inst_entry->inst);
567}
568
569
570template <class MemDepPred, class Impl>
571void
572MemDepUnit<MemDepPred, Impl>::dumpLists()
573{
574 for (ThreadID tid = 0; tid < Impl::MaxThreads; tid++) {
575 cprintf("Instruction list %i size: %i\n",
576 tid, instList[tid].size());
577
578 ListIt inst_list_it = instList[tid].begin();
579 int num = 0;
580
581 while (inst_list_it != instList[tid].end()) {
582 cprintf("Instruction:%i\nPC: %s\n[sn:%i]\n[tid:%i]\nIssued:%i\n"
583 "Squashed:%i\n\n",
584 num, (*inst_list_it)->pcState(),
585 (*inst_list_it)->seqNum,
586 (*inst_list_it)->threadNumber,
587 (*inst_list_it)->isIssued(),
588 (*inst_list_it)->isSquashed());
589 inst_list_it++;
590 ++num;
591 }
592 }
593
594 cprintf("Memory dependence hash size: %i\n", memDepHash.size());
595
596#ifdef DEBUG
597 cprintf("Memory dependence entries: %i\n", MemDepEntry::memdep_count);
598#endif
599}
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