inst_queue_impl.hh revision 13449:2f7efa89c58b
1/*
2 * Copyright (c) 2011-2014 ARM Limited
3 * Copyright (c) 2013 Advanced Micro Devices, Inc.
4 * All rights reserved.
5 *
6 * The license below extends only to copyright in the software and shall
7 * not be construed as granting a license to any other intellectual
8 * property including but not limited to intellectual property relating
9 * to a hardware implementation of the functionality of the software
10 * licensed hereunder.  You may use the software subject to the license
11 * terms below provided that you ensure that this notice is replicated
12 * unmodified and in its entirety in all distributions of the software,
13 * modified or unmodified, in source code or in binary form.
14 *
15 * Copyright (c) 2004-2006 The Regents of The University of Michigan
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Kevin Lim
42 *          Korey Sewell
43 */
44
45#ifndef __CPU_O3_INST_QUEUE_IMPL_HH__
46#define __CPU_O3_INST_QUEUE_IMPL_HH__
47
48#include <limits>
49#include <vector>
50
51#include "base/logging.hh"
52#include "cpu/o3/fu_pool.hh"
53#include "cpu/o3/inst_queue.hh"
54#include "debug/IQ.hh"
55#include "enums/OpClass.hh"
56#include "params/DerivO3CPU.hh"
57#include "sim/core.hh"
58
59// clang complains about std::set being overloaded with Packet::set if
60// we open up the entire namespace std
61using std::list;
62
63template <class Impl>
64InstructionQueue<Impl>::FUCompletion::FUCompletion(const DynInstPtr &_inst,
65    int fu_idx, InstructionQueue<Impl> *iq_ptr)
66    : Event(Stat_Event_Pri, AutoDelete),
67      inst(_inst), fuIdx(fu_idx), iqPtr(iq_ptr), freeFU(false)
68{
69}
70
71template <class Impl>
72void
73InstructionQueue<Impl>::FUCompletion::process()
74{
75    iqPtr->processFUCompletion(inst, freeFU ? fuIdx : -1);
76    inst = NULL;
77}
78
79
80template <class Impl>
81const char *
82InstructionQueue<Impl>::FUCompletion::description() const
83{
84    return "Functional unit completion";
85}
86
87template <class Impl>
88InstructionQueue<Impl>::InstructionQueue(O3CPU *cpu_ptr, IEW *iew_ptr,
89                                         DerivO3CPUParams *params)
90    : cpu(cpu_ptr),
91      iewStage(iew_ptr),
92      fuPool(params->fuPool),
93      numEntries(params->numIQEntries),
94      totalWidth(params->issueWidth),
95      commitToIEWDelay(params->commitToIEWDelay)
96{
97    assert(fuPool);
98
99    numThreads = params->numThreads;
100
101    // Set the number of total physical registers
102    // As the vector registers have two addressing modes, they are added twice
103    numPhysRegs = params->numPhysIntRegs + params->numPhysFloatRegs +
104                    params->numPhysVecRegs +
105                    params->numPhysVecRegs * TheISA::NumVecElemPerVecReg +
106                    params->numPhysCCRegs;
107
108    //Create an entry for each physical register within the
109    //dependency graph.
110    dependGraph.resize(numPhysRegs);
111
112    // Resize the register scoreboard.
113    regScoreboard.resize(numPhysRegs);
114
115    //Initialize Mem Dependence Units
116    for (ThreadID tid = 0; tid < numThreads; tid++) {
117        memDepUnit[tid].init(params, tid);
118        memDepUnit[tid].setIQ(this);
119    }
120
121    resetState();
122
123    std::string policy = params->smtIQPolicy;
124
125    //Convert string to lowercase
126    std::transform(policy.begin(), policy.end(), policy.begin(),
127                   (int(*)(int)) tolower);
128
129    //Figure out resource sharing policy
130    if (policy == "dynamic") {
131        iqPolicy = Dynamic;
132
133        //Set Max Entries to Total ROB Capacity
134        for (ThreadID tid = 0; tid < numThreads; tid++) {
135            maxEntries[tid] = numEntries;
136        }
137
138    } else if (policy == "partitioned") {
139        iqPolicy = Partitioned;
140
141        //@todo:make work if part_amt doesnt divide evenly.
142        int part_amt = numEntries / numThreads;
143
144        //Divide ROB up evenly
145        for (ThreadID tid = 0; tid < numThreads; tid++) {
146            maxEntries[tid] = part_amt;
147        }
148
149        DPRINTF(IQ, "IQ sharing policy set to Partitioned:"
150                "%i entries per thread.\n",part_amt);
151    } else if (policy == "threshold") {
152        iqPolicy = Threshold;
153
154        double threshold =  (double)params->smtIQThreshold / 100;
155
156        int thresholdIQ = (int)((double)threshold * numEntries);
157
158        //Divide up by threshold amount
159        for (ThreadID tid = 0; tid < numThreads; tid++) {
160            maxEntries[tid] = thresholdIQ;
161        }
162
163        DPRINTF(IQ, "IQ sharing policy set to Threshold:"
164                "%i entries per thread.\n",thresholdIQ);
165   } else {
166       panic("Invalid IQ sharing policy. Options are: Dynamic, "
167              "Partitioned, Threshold");
168   }
169}
170
171template <class Impl>
172InstructionQueue<Impl>::~InstructionQueue()
173{
174    dependGraph.reset();
175#ifdef DEBUG
176    cprintf("Nodes traversed: %i, removed: %i\n",
177            dependGraph.nodesTraversed, dependGraph.nodesRemoved);
178#endif
179}
180
181template <class Impl>
182std::string
183InstructionQueue<Impl>::name() const
184{
185    return cpu->name() + ".iq";
186}
187
188template <class Impl>
189void
190InstructionQueue<Impl>::regStats()
191{
192    using namespace Stats;
193    iqInstsAdded
194        .name(name() + ".iqInstsAdded")
195        .desc("Number of instructions added to the IQ (excludes non-spec)")
196        .prereq(iqInstsAdded);
197
198    iqNonSpecInstsAdded
199        .name(name() + ".iqNonSpecInstsAdded")
200        .desc("Number of non-speculative instructions added to the IQ")
201        .prereq(iqNonSpecInstsAdded);
202
203    iqInstsIssued
204        .name(name() + ".iqInstsIssued")
205        .desc("Number of instructions issued")
206        .prereq(iqInstsIssued);
207
208    iqIntInstsIssued
209        .name(name() + ".iqIntInstsIssued")
210        .desc("Number of integer instructions issued")
211        .prereq(iqIntInstsIssued);
212
213    iqFloatInstsIssued
214        .name(name() + ".iqFloatInstsIssued")
215        .desc("Number of float instructions issued")
216        .prereq(iqFloatInstsIssued);
217
218    iqBranchInstsIssued
219        .name(name() + ".iqBranchInstsIssued")
220        .desc("Number of branch instructions issued")
221        .prereq(iqBranchInstsIssued);
222
223    iqMemInstsIssued
224        .name(name() + ".iqMemInstsIssued")
225        .desc("Number of memory instructions issued")
226        .prereq(iqMemInstsIssued);
227
228    iqMiscInstsIssued
229        .name(name() + ".iqMiscInstsIssued")
230        .desc("Number of miscellaneous instructions issued")
231        .prereq(iqMiscInstsIssued);
232
233    iqSquashedInstsIssued
234        .name(name() + ".iqSquashedInstsIssued")
235        .desc("Number of squashed instructions issued")
236        .prereq(iqSquashedInstsIssued);
237
238    iqSquashedInstsExamined
239        .name(name() + ".iqSquashedInstsExamined")
240        .desc("Number of squashed instructions iterated over during squash;"
241              " mainly for profiling")
242        .prereq(iqSquashedInstsExamined);
243
244    iqSquashedOperandsExamined
245        .name(name() + ".iqSquashedOperandsExamined")
246        .desc("Number of squashed operands that are examined and possibly "
247              "removed from graph")
248        .prereq(iqSquashedOperandsExamined);
249
250    iqSquashedNonSpecRemoved
251        .name(name() + ".iqSquashedNonSpecRemoved")
252        .desc("Number of squashed non-spec instructions that were removed")
253        .prereq(iqSquashedNonSpecRemoved);
254/*
255    queueResDist
256        .init(Num_OpClasses, 0, 99, 2)
257        .name(name() + ".IQ:residence:")
258        .desc("cycles from dispatch to issue")
259        .flags(total | pdf | cdf )
260        ;
261    for (int i = 0; i < Num_OpClasses; ++i) {
262        queueResDist.subname(i, opClassStrings[i]);
263    }
264*/
265    numIssuedDist
266        .init(0,totalWidth,1)
267        .name(name() + ".issued_per_cycle")
268        .desc("Number of insts issued each cycle")
269        .flags(pdf)
270        ;
271/*
272    dist_unissued
273        .init(Num_OpClasses+2)
274        .name(name() + ".unissued_cause")
275        .desc("Reason ready instruction not issued")
276        .flags(pdf | dist)
277        ;
278    for (int i=0; i < (Num_OpClasses + 2); ++i) {
279        dist_unissued.subname(i, unissued_names[i]);
280    }
281*/
282    statIssuedInstType
283        .init(numThreads,Enums::Num_OpClass)
284        .name(name() + ".FU_type")
285        .desc("Type of FU issued")
286        .flags(total | pdf | dist)
287        ;
288    statIssuedInstType.ysubnames(Enums::OpClassStrings);
289
290    //
291    //  How long did instructions for a particular FU type wait prior to issue
292    //
293/*
294    issueDelayDist
295        .init(Num_OpClasses,0,99,2)
296        .name(name() + ".")
297        .desc("cycles from operands ready to issue")
298        .flags(pdf | cdf)
299        ;
300
301    for (int i=0; i<Num_OpClasses; ++i) {
302        std::stringstream subname;
303        subname << opClassStrings[i] << "_delay";
304        issueDelayDist.subname(i, subname.str());
305    }
306*/
307    issueRate
308        .name(name() + ".rate")
309        .desc("Inst issue rate")
310        .flags(total)
311        ;
312    issueRate = iqInstsIssued / cpu->numCycles;
313
314    statFuBusy
315        .init(Num_OpClasses)
316        .name(name() + ".fu_full")
317        .desc("attempts to use FU when none available")
318        .flags(pdf | dist)
319        ;
320    for (int i=0; i < Num_OpClasses; ++i) {
321        statFuBusy.subname(i, Enums::OpClassStrings[i]);
322    }
323
324    fuBusy
325        .init(numThreads)
326        .name(name() + ".fu_busy_cnt")
327        .desc("FU busy when requested")
328        .flags(total)
329        ;
330
331    fuBusyRate
332        .name(name() + ".fu_busy_rate")
333        .desc("FU busy rate (busy events/executed inst)")
334        .flags(total)
335        ;
336    fuBusyRate = fuBusy / iqInstsIssued;
337
338    for (ThreadID tid = 0; tid < numThreads; tid++) {
339        // Tell mem dependence unit to reg stats as well.
340        memDepUnit[tid].regStats();
341    }
342
343    intInstQueueReads
344        .name(name() + ".int_inst_queue_reads")
345        .desc("Number of integer instruction queue reads")
346        .flags(total);
347
348    intInstQueueWrites
349        .name(name() + ".int_inst_queue_writes")
350        .desc("Number of integer instruction queue writes")
351        .flags(total);
352
353    intInstQueueWakeupAccesses
354        .name(name() + ".int_inst_queue_wakeup_accesses")
355        .desc("Number of integer instruction queue wakeup accesses")
356        .flags(total);
357
358    fpInstQueueReads
359        .name(name() + ".fp_inst_queue_reads")
360        .desc("Number of floating instruction queue reads")
361        .flags(total);
362
363    fpInstQueueWrites
364        .name(name() + ".fp_inst_queue_writes")
365        .desc("Number of floating instruction queue writes")
366        .flags(total);
367
368    fpInstQueueWakeupAccesses
369        .name(name() + ".fp_inst_queue_wakeup_accesses")
370        .desc("Number of floating instruction queue wakeup accesses")
371        .flags(total);
372
373    vecInstQueueReads
374        .name(name() + ".vec_inst_queue_reads")
375        .desc("Number of vector instruction queue reads")
376        .flags(total);
377
378    vecInstQueueWrites
379        .name(name() + ".vec_inst_queue_writes")
380        .desc("Number of vector instruction queue writes")
381        .flags(total);
382
383    vecInstQueueWakeupAccesses
384        .name(name() + ".vec_inst_queue_wakeup_accesses")
385        .desc("Number of vector instruction queue wakeup accesses")
386        .flags(total);
387
388    intAluAccesses
389        .name(name() + ".int_alu_accesses")
390        .desc("Number of integer alu accesses")
391        .flags(total);
392
393    fpAluAccesses
394        .name(name() + ".fp_alu_accesses")
395        .desc("Number of floating point alu accesses")
396        .flags(total);
397
398    vecAluAccesses
399        .name(name() + ".vec_alu_accesses")
400        .desc("Number of vector alu accesses")
401        .flags(total);
402
403}
404
405template <class Impl>
406void
407InstructionQueue<Impl>::resetState()
408{
409    //Initialize thread IQ counts
410    for (ThreadID tid = 0; tid <numThreads; tid++) {
411        count[tid] = 0;
412        instList[tid].clear();
413    }
414
415    // Initialize the number of free IQ entries.
416    freeEntries = numEntries;
417
418    // Note that in actuality, the registers corresponding to the logical
419    // registers start off as ready.  However this doesn't matter for the
420    // IQ as the instruction should have been correctly told if those
421    // registers are ready in rename.  Thus it can all be initialized as
422    // unready.
423    for (int i = 0; i < numPhysRegs; ++i) {
424        regScoreboard[i] = false;
425    }
426
427    for (ThreadID tid = 0; tid < numThreads; ++tid) {
428        squashedSeqNum[tid] = 0;
429    }
430
431    for (int i = 0; i < Num_OpClasses; ++i) {
432        while (!readyInsts[i].empty())
433            readyInsts[i].pop();
434        queueOnList[i] = false;
435        readyIt[i] = listOrder.end();
436    }
437    nonSpecInsts.clear();
438    listOrder.clear();
439    deferredMemInsts.clear();
440    blockedMemInsts.clear();
441    retryMemInsts.clear();
442    wbOutstanding = 0;
443}
444
445template <class Impl>
446void
447InstructionQueue<Impl>::setActiveThreads(list<ThreadID> *at_ptr)
448{
449    activeThreads = at_ptr;
450}
451
452template <class Impl>
453void
454InstructionQueue<Impl>::setIssueToExecuteQueue(TimeBuffer<IssueStruct> *i2e_ptr)
455{
456      issueToExecuteQueue = i2e_ptr;
457}
458
459template <class Impl>
460void
461InstructionQueue<Impl>::setTimeBuffer(TimeBuffer<TimeStruct> *tb_ptr)
462{
463    timeBuffer = tb_ptr;
464
465    fromCommit = timeBuffer->getWire(-commitToIEWDelay);
466}
467
468template <class Impl>
469bool
470InstructionQueue<Impl>::isDrained() const
471{
472    bool drained = dependGraph.empty() &&
473                   instsToExecute.empty() &&
474                   wbOutstanding == 0;
475    for (ThreadID tid = 0; tid < numThreads; ++tid)
476        drained = drained && memDepUnit[tid].isDrained();
477
478    return drained;
479}
480
481template <class Impl>
482void
483InstructionQueue<Impl>::drainSanityCheck() const
484{
485    assert(dependGraph.empty());
486    assert(instsToExecute.empty());
487    for (ThreadID tid = 0; tid < numThreads; ++tid)
488        memDepUnit[tid].drainSanityCheck();
489}
490
491template <class Impl>
492void
493InstructionQueue<Impl>::takeOverFrom()
494{
495    resetState();
496}
497
498template <class Impl>
499int
500InstructionQueue<Impl>::entryAmount(ThreadID num_threads)
501{
502    if (iqPolicy == Partitioned) {
503        return numEntries / num_threads;
504    } else {
505        return 0;
506    }
507}
508
509
510template <class Impl>
511void
512InstructionQueue<Impl>::resetEntries()
513{
514    if (iqPolicy != Dynamic || numThreads > 1) {
515        int active_threads = activeThreads->size();
516
517        list<ThreadID>::iterator threads = activeThreads->begin();
518        list<ThreadID>::iterator end = activeThreads->end();
519
520        while (threads != end) {
521            ThreadID tid = *threads++;
522
523            if (iqPolicy == Partitioned) {
524                maxEntries[tid] = numEntries / active_threads;
525            } else if (iqPolicy == Threshold && active_threads == 1) {
526                maxEntries[tid] = numEntries;
527            }
528        }
529    }
530}
531
532template <class Impl>
533unsigned
534InstructionQueue<Impl>::numFreeEntries()
535{
536    return freeEntries;
537}
538
539template <class Impl>
540unsigned
541InstructionQueue<Impl>::numFreeEntries(ThreadID tid)
542{
543    return maxEntries[tid] - count[tid];
544}
545
546// Might want to do something more complex if it knows how many instructions
547// will be issued this cycle.
548template <class Impl>
549bool
550InstructionQueue<Impl>::isFull()
551{
552    if (freeEntries == 0) {
553        return(true);
554    } else {
555        return(false);
556    }
557}
558
559template <class Impl>
560bool
561InstructionQueue<Impl>::isFull(ThreadID tid)
562{
563    if (numFreeEntries(tid) == 0) {
564        return(true);
565    } else {
566        return(false);
567    }
568}
569
570template <class Impl>
571bool
572InstructionQueue<Impl>::hasReadyInsts()
573{
574    if (!listOrder.empty()) {
575        return true;
576    }
577
578    for (int i = 0; i < Num_OpClasses; ++i) {
579        if (!readyInsts[i].empty()) {
580            return true;
581        }
582    }
583
584    return false;
585}
586
587template <class Impl>
588void
589InstructionQueue<Impl>::insert(const DynInstPtr &new_inst)
590{
591    if (new_inst->isFloating()) {
592        fpInstQueueWrites++;
593    } else if (new_inst->isVector()) {
594        vecInstQueueWrites++;
595    } else {
596        intInstQueueWrites++;
597    }
598    // Make sure the instruction is valid
599    assert(new_inst);
600
601    DPRINTF(IQ, "Adding instruction [sn:%lli] PC %s to the IQ.\n",
602            new_inst->seqNum, new_inst->pcState());
603
604    assert(freeEntries != 0);
605
606    instList[new_inst->threadNumber].push_back(new_inst);
607
608    --freeEntries;
609
610    new_inst->setInIQ();
611
612    // Look through its source registers (physical regs), and mark any
613    // dependencies.
614    addToDependents(new_inst);
615
616    // Have this instruction set itself as the producer of its destination
617    // register(s).
618    addToProducers(new_inst);
619
620    if (new_inst->isMemRef()) {
621        memDepUnit[new_inst->threadNumber].insert(new_inst);
622    } else {
623        addIfReady(new_inst);
624    }
625
626    ++iqInstsAdded;
627
628    count[new_inst->threadNumber]++;
629
630    assert(freeEntries == (numEntries - countInsts()));
631}
632
633template <class Impl>
634void
635InstructionQueue<Impl>::insertNonSpec(const DynInstPtr &new_inst)
636{
637    // @todo: Clean up this code; can do it by setting inst as unable
638    // to issue, then calling normal insert on the inst.
639    if (new_inst->isFloating()) {
640        fpInstQueueWrites++;
641    } else if (new_inst->isVector()) {
642        vecInstQueueWrites++;
643    } else {
644        intInstQueueWrites++;
645    }
646
647    assert(new_inst);
648
649    nonSpecInsts[new_inst->seqNum] = new_inst;
650
651    DPRINTF(IQ, "Adding non-speculative instruction [sn:%lli] PC %s "
652            "to the IQ.\n",
653            new_inst->seqNum, new_inst->pcState());
654
655    assert(freeEntries != 0);
656
657    instList[new_inst->threadNumber].push_back(new_inst);
658
659    --freeEntries;
660
661    new_inst->setInIQ();
662
663    // Have this instruction set itself as the producer of its destination
664    // register(s).
665    addToProducers(new_inst);
666
667    // If it's a memory instruction, add it to the memory dependency
668    // unit.
669    if (new_inst->isMemRef()) {
670        memDepUnit[new_inst->threadNumber].insertNonSpec(new_inst);
671    }
672
673    ++iqNonSpecInstsAdded;
674
675    count[new_inst->threadNumber]++;
676
677    assert(freeEntries == (numEntries - countInsts()));
678}
679
680template <class Impl>
681void
682InstructionQueue<Impl>::insertBarrier(const DynInstPtr &barr_inst)
683{
684    memDepUnit[barr_inst->threadNumber].insertBarrier(barr_inst);
685
686    insertNonSpec(barr_inst);
687}
688
689template <class Impl>
690typename Impl::DynInstPtr
691InstructionQueue<Impl>::getInstToExecute()
692{
693    assert(!instsToExecute.empty());
694    DynInstPtr inst = std::move(instsToExecute.front());
695    instsToExecute.pop_front();
696    if (inst->isFloating()) {
697        fpInstQueueReads++;
698    } else if (inst->isVector()) {
699        vecInstQueueReads++;
700    } else {
701        intInstQueueReads++;
702    }
703    return inst;
704}
705
706template <class Impl>
707void
708InstructionQueue<Impl>::addToOrderList(OpClass op_class)
709{
710    assert(!readyInsts[op_class].empty());
711
712    ListOrderEntry queue_entry;
713
714    queue_entry.queueType = op_class;
715
716    queue_entry.oldestInst = readyInsts[op_class].top()->seqNum;
717
718    ListOrderIt list_it = listOrder.begin();
719    ListOrderIt list_end_it = listOrder.end();
720
721    while (list_it != list_end_it) {
722        if ((*list_it).oldestInst > queue_entry.oldestInst) {
723            break;
724        }
725
726        list_it++;
727    }
728
729    readyIt[op_class] = listOrder.insert(list_it, queue_entry);
730    queueOnList[op_class] = true;
731}
732
733template <class Impl>
734void
735InstructionQueue<Impl>::moveToYoungerInst(ListOrderIt list_order_it)
736{
737    // Get iterator of next item on the list
738    // Delete the original iterator
739    // Determine if the next item is either the end of the list or younger
740    // than the new instruction.  If so, then add in a new iterator right here.
741    // If not, then move along.
742    ListOrderEntry queue_entry;
743    OpClass op_class = (*list_order_it).queueType;
744    ListOrderIt next_it = list_order_it;
745
746    ++next_it;
747
748    queue_entry.queueType = op_class;
749    queue_entry.oldestInst = readyInsts[op_class].top()->seqNum;
750
751    while (next_it != listOrder.end() &&
752           (*next_it).oldestInst < queue_entry.oldestInst) {
753        ++next_it;
754    }
755
756    readyIt[op_class] = listOrder.insert(next_it, queue_entry);
757}
758
759template <class Impl>
760void
761InstructionQueue<Impl>::processFUCompletion(const DynInstPtr &inst, int fu_idx)
762{
763    DPRINTF(IQ, "Processing FU completion [sn:%lli]\n", inst->seqNum);
764    assert(!cpu->switchedOut());
765    // The CPU could have been sleeping until this op completed (*extremely*
766    // long latency op).  Wake it if it was.  This may be overkill.
767   --wbOutstanding;
768    iewStage->wakeCPU();
769
770    if (fu_idx > -1)
771        fuPool->freeUnitNextCycle(fu_idx);
772
773    // @todo: Ensure that these FU Completions happen at the beginning
774    // of a cycle, otherwise they could add too many instructions to
775    // the queue.
776    issueToExecuteQueue->access(-1)->size++;
777    instsToExecute.push_back(inst);
778}
779
780// @todo: Figure out a better way to remove the squashed items from the
781// lists.  Checking the top item of each list to see if it's squashed
782// wastes time and forces jumps.
783template <class Impl>
784void
785InstructionQueue<Impl>::scheduleReadyInsts()
786{
787    DPRINTF(IQ, "Attempting to schedule ready instructions from "
788            "the IQ.\n");
789
790    IssueStruct *i2e_info = issueToExecuteQueue->access(0);
791
792    DynInstPtr mem_inst;
793    while (mem_inst = std::move(getDeferredMemInstToExecute())) {
794        addReadyMemInst(mem_inst);
795    }
796
797    // See if any cache blocked instructions are able to be executed
798    while (mem_inst = std::move(getBlockedMemInstToExecute())) {
799        addReadyMemInst(mem_inst);
800    }
801
802    // Have iterator to head of the list
803    // While I haven't exceeded bandwidth or reached the end of the list,
804    // Try to get a FU that can do what this op needs.
805    // If successful, change the oldestInst to the new top of the list, put
806    // the queue in the proper place in the list.
807    // Increment the iterator.
808    // This will avoid trying to schedule a certain op class if there are no
809    // FUs that handle it.
810    int total_issued = 0;
811    ListOrderIt order_it = listOrder.begin();
812    ListOrderIt order_end_it = listOrder.end();
813
814    while (total_issued < totalWidth && order_it != order_end_it) {
815        OpClass op_class = (*order_it).queueType;
816
817        assert(!readyInsts[op_class].empty());
818
819        DynInstPtr issuing_inst = readyInsts[op_class].top();
820
821        if (issuing_inst->isFloating()) {
822            fpInstQueueReads++;
823        } else if (issuing_inst->isVector()) {
824            vecInstQueueReads++;
825        } else {
826            intInstQueueReads++;
827        }
828
829        assert(issuing_inst->seqNum == (*order_it).oldestInst);
830
831        if (issuing_inst->isSquashed()) {
832            readyInsts[op_class].pop();
833
834            if (!readyInsts[op_class].empty()) {
835                moveToYoungerInst(order_it);
836            } else {
837                readyIt[op_class] = listOrder.end();
838                queueOnList[op_class] = false;
839            }
840
841            listOrder.erase(order_it++);
842
843            ++iqSquashedInstsIssued;
844
845            continue;
846        }
847
848        int idx = FUPool::NoCapableFU;
849        Cycles op_latency = Cycles(1);
850        ThreadID tid = issuing_inst->threadNumber;
851
852        if (op_class != No_OpClass) {
853            idx = fuPool->getUnit(op_class);
854            if (issuing_inst->isFloating()) {
855                fpAluAccesses++;
856            } else if (issuing_inst->isVector()) {
857                vecAluAccesses++;
858            } else {
859                intAluAccesses++;
860            }
861            if (idx > FUPool::NoFreeFU) {
862                op_latency = fuPool->getOpLatency(op_class);
863            }
864        }
865
866        // If we have an instruction that doesn't require a FU, or a
867        // valid FU, then schedule for execution.
868        if (idx != FUPool::NoFreeFU) {
869            if (op_latency == Cycles(1)) {
870                i2e_info->size++;
871                instsToExecute.push_back(issuing_inst);
872
873                // Add the FU onto the list of FU's to be freed next
874                // cycle if we used one.
875                if (idx >= 0)
876                    fuPool->freeUnitNextCycle(idx);
877            } else {
878                bool pipelined = fuPool->isPipelined(op_class);
879                // Generate completion event for the FU
880                ++wbOutstanding;
881                FUCompletion *execution = new FUCompletion(issuing_inst,
882                                                           idx, this);
883
884                cpu->schedule(execution,
885                              cpu->clockEdge(Cycles(op_latency - 1)));
886
887                if (!pipelined) {
888                    // If FU isn't pipelined, then it must be freed
889                    // upon the execution completing.
890                    execution->setFreeFU();
891                } else {
892                    // Add the FU onto the list of FU's to be freed next cycle.
893                    fuPool->freeUnitNextCycle(idx);
894                }
895            }
896
897            DPRINTF(IQ, "Thread %i: Issuing instruction PC %s "
898                    "[sn:%lli]\n",
899                    tid, issuing_inst->pcState(),
900                    issuing_inst->seqNum);
901
902            readyInsts[op_class].pop();
903
904            if (!readyInsts[op_class].empty()) {
905                moveToYoungerInst(order_it);
906            } else {
907                readyIt[op_class] = listOrder.end();
908                queueOnList[op_class] = false;
909            }
910
911            issuing_inst->setIssued();
912            ++total_issued;
913
914#if TRACING_ON
915            issuing_inst->issueTick = curTick() - issuing_inst->fetchTick;
916#endif
917
918            if (!issuing_inst->isMemRef()) {
919                // Memory instructions can not be freed from the IQ until they
920                // complete.
921                ++freeEntries;
922                count[tid]--;
923                issuing_inst->clearInIQ();
924            } else {
925                memDepUnit[tid].issue(issuing_inst);
926            }
927
928            listOrder.erase(order_it++);
929            statIssuedInstType[tid][op_class]++;
930        } else {
931            statFuBusy[op_class]++;
932            fuBusy[tid]++;
933            ++order_it;
934        }
935    }
936
937    numIssuedDist.sample(total_issued);
938    iqInstsIssued+= total_issued;
939
940    // If we issued any instructions, tell the CPU we had activity.
941    // @todo If the way deferred memory instructions are handeled due to
942    // translation changes then the deferredMemInsts condition should be removed
943    // from the code below.
944    if (total_issued || !retryMemInsts.empty() || !deferredMemInsts.empty()) {
945        cpu->activityThisCycle();
946    } else {
947        DPRINTF(IQ, "Not able to schedule any instructions.\n");
948    }
949}
950
951template <class Impl>
952void
953InstructionQueue<Impl>::scheduleNonSpec(const InstSeqNum &inst)
954{
955    DPRINTF(IQ, "Marking nonspeculative instruction [sn:%lli] as ready "
956            "to execute.\n", inst);
957
958    NonSpecMapIt inst_it = nonSpecInsts.find(inst);
959
960    assert(inst_it != nonSpecInsts.end());
961
962    ThreadID tid = (*inst_it).second->threadNumber;
963
964    (*inst_it).second->setAtCommit();
965
966    (*inst_it).second->setCanIssue();
967
968    if (!(*inst_it).second->isMemRef()) {
969        addIfReady((*inst_it).second);
970    } else {
971        memDepUnit[tid].nonSpecInstReady((*inst_it).second);
972    }
973
974    (*inst_it).second = NULL;
975
976    nonSpecInsts.erase(inst_it);
977}
978
979template <class Impl>
980void
981InstructionQueue<Impl>::commit(const InstSeqNum &inst, ThreadID tid)
982{
983    DPRINTF(IQ, "[tid:%i]: Committing instructions older than [sn:%i]\n",
984            tid,inst);
985
986    ListIt iq_it = instList[tid].begin();
987
988    while (iq_it != instList[tid].end() &&
989           (*iq_it)->seqNum <= inst) {
990        ++iq_it;
991        instList[tid].pop_front();
992    }
993
994    assert(freeEntries == (numEntries - countInsts()));
995}
996
997template <class Impl>
998int
999InstructionQueue<Impl>::wakeDependents(const DynInstPtr &completed_inst)
1000{
1001    int dependents = 0;
1002
1003    // The instruction queue here takes care of both floating and int ops
1004    if (completed_inst->isFloating()) {
1005        fpInstQueueWakeupAccesses++;
1006    } else if (completed_inst->isVector()) {
1007        vecInstQueueWakeupAccesses++;
1008    } else {
1009        intInstQueueWakeupAccesses++;
1010    }
1011
1012    DPRINTF(IQ, "Waking dependents of completed instruction.\n");
1013
1014    assert(!completed_inst->isSquashed());
1015
1016    // Tell the memory dependence unit to wake any dependents on this
1017    // instruction if it is a memory instruction.  Also complete the memory
1018    // instruction at this point since we know it executed without issues.
1019    // @todo: Might want to rename "completeMemInst" to something that
1020    // indicates that it won't need to be replayed, and call this
1021    // earlier.  Might not be a big deal.
1022    if (completed_inst->isMemRef()) {
1023        memDepUnit[completed_inst->threadNumber].wakeDependents(completed_inst);
1024        completeMemInst(completed_inst);
1025    } else if (completed_inst->isMemBarrier() ||
1026               completed_inst->isWriteBarrier()) {
1027        memDepUnit[completed_inst->threadNumber].completeBarrier(completed_inst);
1028    }
1029
1030    for (int dest_reg_idx = 0;
1031         dest_reg_idx < completed_inst->numDestRegs();
1032         dest_reg_idx++)
1033    {
1034        PhysRegIdPtr dest_reg =
1035            completed_inst->renamedDestRegIdx(dest_reg_idx);
1036
1037        // Special case of uniq or control registers.  They are not
1038        // handled by the IQ and thus have no dependency graph entry.
1039        if (dest_reg->isFixedMapping()) {
1040            DPRINTF(IQ, "Reg %d [%s] is part of a fix mapping, skipping\n",
1041                    dest_reg->index(), dest_reg->className());
1042            continue;
1043        }
1044
1045        DPRINTF(IQ, "Waking any dependents on register %i (%s).\n",
1046                dest_reg->index(),
1047                dest_reg->className());
1048
1049        //Go through the dependency chain, marking the registers as
1050        //ready within the waiting instructions.
1051        DynInstPtr dep_inst = dependGraph.pop(dest_reg->flatIndex());
1052
1053        while (dep_inst) {
1054            DPRINTF(IQ, "Waking up a dependent instruction, [sn:%lli] "
1055                    "PC %s.\n", dep_inst->seqNum, dep_inst->pcState());
1056
1057            // Might want to give more information to the instruction
1058            // so that it knows which of its source registers is
1059            // ready.  However that would mean that the dependency
1060            // graph entries would need to hold the src_reg_idx.
1061            dep_inst->markSrcRegReady();
1062
1063            addIfReady(dep_inst);
1064
1065            dep_inst = dependGraph.pop(dest_reg->flatIndex());
1066
1067            ++dependents;
1068        }
1069
1070        // Reset the head node now that all of its dependents have
1071        // been woken up.
1072        assert(dependGraph.empty(dest_reg->flatIndex()));
1073        dependGraph.clearInst(dest_reg->flatIndex());
1074
1075        // Mark the scoreboard as having that register ready.
1076        regScoreboard[dest_reg->flatIndex()] = true;
1077    }
1078    return dependents;
1079}
1080
1081template <class Impl>
1082void
1083InstructionQueue<Impl>::addReadyMemInst(const DynInstPtr &ready_inst)
1084{
1085    OpClass op_class = ready_inst->opClass();
1086
1087    readyInsts[op_class].push(ready_inst);
1088
1089    // Will need to reorder the list if either a queue is not on the list,
1090    // or it has an older instruction than last time.
1091    if (!queueOnList[op_class]) {
1092        addToOrderList(op_class);
1093    } else if (readyInsts[op_class].top()->seqNum  <
1094               (*readyIt[op_class]).oldestInst) {
1095        listOrder.erase(readyIt[op_class]);
1096        addToOrderList(op_class);
1097    }
1098
1099    DPRINTF(IQ, "Instruction is ready to issue, putting it onto "
1100            "the ready list, PC %s opclass:%i [sn:%lli].\n",
1101            ready_inst->pcState(), op_class, ready_inst->seqNum);
1102}
1103
1104template <class Impl>
1105void
1106InstructionQueue<Impl>::rescheduleMemInst(const DynInstPtr &resched_inst)
1107{
1108    DPRINTF(IQ, "Rescheduling mem inst [sn:%lli]\n", resched_inst->seqNum);
1109
1110    // Reset DTB translation state
1111    resched_inst->translationStarted(false);
1112    resched_inst->translationCompleted(false);
1113
1114    resched_inst->clearCanIssue();
1115    memDepUnit[resched_inst->threadNumber].reschedule(resched_inst);
1116}
1117
1118template <class Impl>
1119void
1120InstructionQueue<Impl>::replayMemInst(const DynInstPtr &replay_inst)
1121{
1122    memDepUnit[replay_inst->threadNumber].replay();
1123}
1124
1125template <class Impl>
1126void
1127InstructionQueue<Impl>::completeMemInst(const DynInstPtr &completed_inst)
1128{
1129    ThreadID tid = completed_inst->threadNumber;
1130
1131    DPRINTF(IQ, "Completing mem instruction PC: %s [sn:%lli]\n",
1132            completed_inst->pcState(), completed_inst->seqNum);
1133
1134    ++freeEntries;
1135
1136    completed_inst->memOpDone(true);
1137
1138    memDepUnit[tid].completed(completed_inst);
1139    count[tid]--;
1140}
1141
1142template <class Impl>
1143void
1144InstructionQueue<Impl>::deferMemInst(const DynInstPtr &deferred_inst)
1145{
1146    deferredMemInsts.push_back(deferred_inst);
1147}
1148
1149template <class Impl>
1150void
1151InstructionQueue<Impl>::blockMemInst(const DynInstPtr &blocked_inst)
1152{
1153    blocked_inst->translationStarted(false);
1154    blocked_inst->translationCompleted(false);
1155
1156    blocked_inst->clearIssued();
1157    blocked_inst->clearCanIssue();
1158    blockedMemInsts.push_back(blocked_inst);
1159}
1160
1161template <class Impl>
1162void
1163InstructionQueue<Impl>::cacheUnblocked()
1164{
1165    retryMemInsts.splice(retryMemInsts.end(), blockedMemInsts);
1166    // Get the CPU ticking again
1167    cpu->wakeCPU();
1168}
1169
1170template <class Impl>
1171typename Impl::DynInstPtr
1172InstructionQueue<Impl>::getDeferredMemInstToExecute()
1173{
1174    for (ListIt it = deferredMemInsts.begin(); it != deferredMemInsts.end();
1175         ++it) {
1176        if ((*it)->translationCompleted() || (*it)->isSquashed()) {
1177            DynInstPtr mem_inst = std::move(*it);
1178            deferredMemInsts.erase(it);
1179            return mem_inst;
1180        }
1181    }
1182    return nullptr;
1183}
1184
1185template <class Impl>
1186typename Impl::DynInstPtr
1187InstructionQueue<Impl>::getBlockedMemInstToExecute()
1188{
1189    if (retryMemInsts.empty()) {
1190        return nullptr;
1191    } else {
1192        DynInstPtr mem_inst = std::move(retryMemInsts.front());
1193        retryMemInsts.pop_front();
1194        return mem_inst;
1195    }
1196}
1197
1198template <class Impl>
1199void
1200InstructionQueue<Impl>::violation(const DynInstPtr &store,
1201                                  const DynInstPtr &faulting_load)
1202{
1203    intInstQueueWrites++;
1204    memDepUnit[store->threadNumber].violation(store, faulting_load);
1205}
1206
1207template <class Impl>
1208void
1209InstructionQueue<Impl>::squash(ThreadID tid)
1210{
1211    DPRINTF(IQ, "[tid:%i]: Starting to squash instructions in "
1212            "the IQ.\n", tid);
1213
1214    // Read instruction sequence number of last instruction out of the
1215    // time buffer.
1216    squashedSeqNum[tid] = fromCommit->commitInfo[tid].doneSeqNum;
1217
1218    doSquash(tid);
1219
1220    // Also tell the memory dependence unit to squash.
1221    memDepUnit[tid].squash(squashedSeqNum[tid], tid);
1222}
1223
1224template <class Impl>
1225void
1226InstructionQueue<Impl>::doSquash(ThreadID tid)
1227{
1228    // Start at the tail.
1229    ListIt squash_it = instList[tid].end();
1230    --squash_it;
1231
1232    DPRINTF(IQ, "[tid:%i]: Squashing until sequence number %i!\n",
1233            tid, squashedSeqNum[tid]);
1234
1235    // Squash any instructions younger than the squashed sequence number
1236    // given.
1237    while (squash_it != instList[tid].end() &&
1238           (*squash_it)->seqNum > squashedSeqNum[tid]) {
1239
1240        DynInstPtr squashed_inst = (*squash_it);
1241        if (squashed_inst->isFloating()) {
1242            fpInstQueueWrites++;
1243        } else if (squashed_inst->isVector()) {
1244            vecInstQueueWrites++;
1245        } else {
1246            intInstQueueWrites++;
1247        }
1248
1249        // Only handle the instruction if it actually is in the IQ and
1250        // hasn't already been squashed in the IQ.
1251        if (squashed_inst->threadNumber != tid ||
1252            squashed_inst->isSquashedInIQ()) {
1253            --squash_it;
1254            continue;
1255        }
1256
1257        if (!squashed_inst->isIssued() ||
1258            (squashed_inst->isMemRef() &&
1259             !squashed_inst->memOpDone())) {
1260
1261            DPRINTF(IQ, "[tid:%i]: Instruction [sn:%lli] PC %s squashed.\n",
1262                    tid, squashed_inst->seqNum, squashed_inst->pcState());
1263
1264            bool is_acq_rel = squashed_inst->isMemBarrier() &&
1265                         (squashed_inst->isLoad() ||
1266                           (squashed_inst->isStore() &&
1267                             !squashed_inst->isStoreConditional()));
1268
1269            // Remove the instruction from the dependency list.
1270            if (is_acq_rel ||
1271                (!squashed_inst->isNonSpeculative() &&
1272                 !squashed_inst->isStoreConditional() &&
1273                 !squashed_inst->isMemBarrier() &&
1274                 !squashed_inst->isWriteBarrier())) {
1275
1276                for (int src_reg_idx = 0;
1277                     src_reg_idx < squashed_inst->numSrcRegs();
1278                     src_reg_idx++)
1279                {
1280                    PhysRegIdPtr src_reg =
1281                        squashed_inst->renamedSrcRegIdx(src_reg_idx);
1282
1283                    // Only remove it from the dependency graph if it
1284                    // was placed there in the first place.
1285
1286                    // Instead of doing a linked list traversal, we
1287                    // can just remove these squashed instructions
1288                    // either at issue time, or when the register is
1289                    // overwritten.  The only downside to this is it
1290                    // leaves more room for error.
1291
1292                    if (!squashed_inst->isReadySrcRegIdx(src_reg_idx) &&
1293                        !src_reg->isFixedMapping()) {
1294                        dependGraph.remove(src_reg->flatIndex(),
1295                                           squashed_inst);
1296                    }
1297
1298
1299                    ++iqSquashedOperandsExamined;
1300                }
1301            } else if (!squashed_inst->isStoreConditional() ||
1302                       !squashed_inst->isCompleted()) {
1303                NonSpecMapIt ns_inst_it =
1304                    nonSpecInsts.find(squashed_inst->seqNum);
1305
1306                // we remove non-speculative instructions from
1307                // nonSpecInsts already when they are ready, and so we
1308                // cannot always expect to find them
1309                if (ns_inst_it == nonSpecInsts.end()) {
1310                    // loads that became ready but stalled on a
1311                    // blocked cache are alreayd removed from
1312                    // nonSpecInsts, and have not faulted
1313                    assert(squashed_inst->getFault() != NoFault ||
1314                           squashed_inst->isMemRef());
1315                } else {
1316
1317                    (*ns_inst_it).second = NULL;
1318
1319                    nonSpecInsts.erase(ns_inst_it);
1320
1321                    ++iqSquashedNonSpecRemoved;
1322                }
1323            }
1324
1325            // Might want to also clear out the head of the dependency graph.
1326
1327            // Mark it as squashed within the IQ.
1328            squashed_inst->setSquashedInIQ();
1329
1330            // @todo: Remove this hack where several statuses are set so the
1331            // inst will flow through the rest of the pipeline.
1332            squashed_inst->setIssued();
1333            squashed_inst->setCanCommit();
1334            squashed_inst->clearInIQ();
1335
1336            //Update Thread IQ Count
1337            count[squashed_inst->threadNumber]--;
1338
1339            ++freeEntries;
1340        }
1341
1342        // IQ clears out the heads of the dependency graph only when
1343        // instructions reach writeback stage. If an instruction is squashed
1344        // before writeback stage, its head of dependency graph would not be
1345        // cleared out; it holds the instruction's DynInstPtr. This prevents
1346        // freeing the squashed instruction's DynInst.
1347        // Thus, we need to manually clear out the squashed instructions' heads
1348        // of dependency graph.
1349        for (int dest_reg_idx = 0;
1350             dest_reg_idx < squashed_inst->numDestRegs();
1351             dest_reg_idx++)
1352        {
1353            PhysRegIdPtr dest_reg =
1354                squashed_inst->renamedDestRegIdx(dest_reg_idx);
1355            if (dest_reg->isFixedMapping()){
1356                continue;
1357            }
1358            assert(dependGraph.empty(dest_reg->flatIndex()));
1359            dependGraph.clearInst(dest_reg->flatIndex());
1360        }
1361        instList[tid].erase(squash_it--);
1362        ++iqSquashedInstsExamined;
1363    }
1364}
1365
1366template <class Impl>
1367bool
1368InstructionQueue<Impl>::addToDependents(const DynInstPtr &new_inst)
1369{
1370    // Loop through the instruction's source registers, adding
1371    // them to the dependency list if they are not ready.
1372    int8_t total_src_regs = new_inst->numSrcRegs();
1373    bool return_val = false;
1374
1375    for (int src_reg_idx = 0;
1376         src_reg_idx < total_src_regs;
1377         src_reg_idx++)
1378    {
1379        // Only add it to the dependency graph if it's not ready.
1380        if (!new_inst->isReadySrcRegIdx(src_reg_idx)) {
1381            PhysRegIdPtr src_reg = new_inst->renamedSrcRegIdx(src_reg_idx);
1382
1383            // Check the IQ's scoreboard to make sure the register
1384            // hasn't become ready while the instruction was in flight
1385            // between stages.  Only if it really isn't ready should
1386            // it be added to the dependency graph.
1387            if (src_reg->isFixedMapping()) {
1388                continue;
1389            } else if (!regScoreboard[src_reg->flatIndex()]) {
1390                DPRINTF(IQ, "Instruction PC %s has src reg %i (%s) that "
1391                        "is being added to the dependency chain.\n",
1392                        new_inst->pcState(), src_reg->index(),
1393                        src_reg->className());
1394
1395                dependGraph.insert(src_reg->flatIndex(), new_inst);
1396
1397                // Change the return value to indicate that something
1398                // was added to the dependency graph.
1399                return_val = true;
1400            } else {
1401                DPRINTF(IQ, "Instruction PC %s has src reg %i (%s) that "
1402                        "became ready before it reached the IQ.\n",
1403                        new_inst->pcState(), src_reg->index(),
1404                        src_reg->className());
1405                // Mark a register ready within the instruction.
1406                new_inst->markSrcRegReady(src_reg_idx);
1407            }
1408        }
1409    }
1410
1411    return return_val;
1412}
1413
1414template <class Impl>
1415void
1416InstructionQueue<Impl>::addToProducers(const DynInstPtr &new_inst)
1417{
1418    // Nothing really needs to be marked when an instruction becomes
1419    // the producer of a register's value, but for convenience a ptr
1420    // to the producing instruction will be placed in the head node of
1421    // the dependency links.
1422    int8_t total_dest_regs = new_inst->numDestRegs();
1423
1424    for (int dest_reg_idx = 0;
1425         dest_reg_idx < total_dest_regs;
1426         dest_reg_idx++)
1427    {
1428        PhysRegIdPtr dest_reg = new_inst->renamedDestRegIdx(dest_reg_idx);
1429
1430        // Some registers have fixed mapping, and there is no need to track
1431        // dependencies as these instructions must be executed at commit.
1432        if (dest_reg->isFixedMapping()) {
1433            continue;
1434        }
1435
1436        if (!dependGraph.empty(dest_reg->flatIndex())) {
1437            dependGraph.dump();
1438            panic("Dependency graph %i (%s) (flat: %i) not empty!",
1439                  dest_reg->index(), dest_reg->className(),
1440                  dest_reg->flatIndex());
1441        }
1442
1443        dependGraph.setInst(dest_reg->flatIndex(), new_inst);
1444
1445        // Mark the scoreboard to say it's not yet ready.
1446        regScoreboard[dest_reg->flatIndex()] = false;
1447    }
1448}
1449
1450template <class Impl>
1451void
1452InstructionQueue<Impl>::addIfReady(const DynInstPtr &inst)
1453{
1454    // If the instruction now has all of its source registers
1455    // available, then add it to the list of ready instructions.
1456    if (inst->readyToIssue()) {
1457
1458        //Add the instruction to the proper ready list.
1459        if (inst->isMemRef()) {
1460
1461            DPRINTF(IQ, "Checking if memory instruction can issue.\n");
1462
1463            // Message to the mem dependence unit that this instruction has
1464            // its registers ready.
1465            memDepUnit[inst->threadNumber].regsReady(inst);
1466
1467            return;
1468        }
1469
1470        OpClass op_class = inst->opClass();
1471
1472        DPRINTF(IQ, "Instruction is ready to issue, putting it onto "
1473                "the ready list, PC %s opclass:%i [sn:%lli].\n",
1474                inst->pcState(), op_class, inst->seqNum);
1475
1476        readyInsts[op_class].push(inst);
1477
1478        // Will need to reorder the list if either a queue is not on the list,
1479        // or it has an older instruction than last time.
1480        if (!queueOnList[op_class]) {
1481            addToOrderList(op_class);
1482        } else if (readyInsts[op_class].top()->seqNum  <
1483                   (*readyIt[op_class]).oldestInst) {
1484            listOrder.erase(readyIt[op_class]);
1485            addToOrderList(op_class);
1486        }
1487    }
1488}
1489
1490template <class Impl>
1491int
1492InstructionQueue<Impl>::countInsts()
1493{
1494#if 0
1495    //ksewell:This works but definitely could use a cleaner write
1496    //with a more intuitive way of counting. Right now it's
1497    //just brute force ....
1498    // Change the #if if you want to use this method.
1499    int total_insts = 0;
1500
1501    for (ThreadID tid = 0; tid < numThreads; ++tid) {
1502        ListIt count_it = instList[tid].begin();
1503
1504        while (count_it != instList[tid].end()) {
1505            if (!(*count_it)->isSquashed() && !(*count_it)->isSquashedInIQ()) {
1506                if (!(*count_it)->isIssued()) {
1507                    ++total_insts;
1508                } else if ((*count_it)->isMemRef() &&
1509                           !(*count_it)->memOpDone) {
1510                    // Loads that have not been marked as executed still count
1511                    // towards the total instructions.
1512                    ++total_insts;
1513                }
1514            }
1515
1516            ++count_it;
1517        }
1518    }
1519
1520    return total_insts;
1521#else
1522    return numEntries - freeEntries;
1523#endif
1524}
1525
1526template <class Impl>
1527void
1528InstructionQueue<Impl>::dumpLists()
1529{
1530    for (int i = 0; i < Num_OpClasses; ++i) {
1531        cprintf("Ready list %i size: %i\n", i, readyInsts[i].size());
1532
1533        cprintf("\n");
1534    }
1535
1536    cprintf("Non speculative list size: %i\n", nonSpecInsts.size());
1537
1538    NonSpecMapIt non_spec_it = nonSpecInsts.begin();
1539    NonSpecMapIt non_spec_end_it = nonSpecInsts.end();
1540
1541    cprintf("Non speculative list: ");
1542
1543    while (non_spec_it != non_spec_end_it) {
1544        cprintf("%s [sn:%lli]", (*non_spec_it).second->pcState(),
1545                (*non_spec_it).second->seqNum);
1546        ++non_spec_it;
1547    }
1548
1549    cprintf("\n");
1550
1551    ListOrderIt list_order_it = listOrder.begin();
1552    ListOrderIt list_order_end_it = listOrder.end();
1553    int i = 1;
1554
1555    cprintf("List order: ");
1556
1557    while (list_order_it != list_order_end_it) {
1558        cprintf("%i OpClass:%i [sn:%lli] ", i, (*list_order_it).queueType,
1559                (*list_order_it).oldestInst);
1560
1561        ++list_order_it;
1562        ++i;
1563    }
1564
1565    cprintf("\n");
1566}
1567
1568
1569template <class Impl>
1570void
1571InstructionQueue<Impl>::dumpInsts()
1572{
1573    for (ThreadID tid = 0; tid < numThreads; ++tid) {
1574        int num = 0;
1575        int valid_num = 0;
1576        ListIt inst_list_it = instList[tid].begin();
1577
1578        while (inst_list_it != instList[tid].end()) {
1579            cprintf("Instruction:%i\n", num);
1580            if (!(*inst_list_it)->isSquashed()) {
1581                if (!(*inst_list_it)->isIssued()) {
1582                    ++valid_num;
1583                    cprintf("Count:%i\n", valid_num);
1584                } else if ((*inst_list_it)->isMemRef() &&
1585                           !(*inst_list_it)->memOpDone()) {
1586                    // Loads that have not been marked as executed
1587                    // still count towards the total instructions.
1588                    ++valid_num;
1589                    cprintf("Count:%i\n", valid_num);
1590                }
1591            }
1592
1593            cprintf("PC: %s\n[sn:%lli]\n[tid:%i]\n"
1594                    "Issued:%i\nSquashed:%i\n",
1595                    (*inst_list_it)->pcState(),
1596                    (*inst_list_it)->seqNum,
1597                    (*inst_list_it)->threadNumber,
1598                    (*inst_list_it)->isIssued(),
1599                    (*inst_list_it)->isSquashed());
1600
1601            if ((*inst_list_it)->isMemRef()) {
1602                cprintf("MemOpDone:%i\n", (*inst_list_it)->memOpDone());
1603            }
1604
1605            cprintf("\n");
1606
1607            inst_list_it++;
1608            ++num;
1609        }
1610    }
1611
1612    cprintf("Insts to Execute list:\n");
1613
1614    int num = 0;
1615    int valid_num = 0;
1616    ListIt inst_list_it = instsToExecute.begin();
1617
1618    while (inst_list_it != instsToExecute.end())
1619    {
1620        cprintf("Instruction:%i\n",
1621                num);
1622        if (!(*inst_list_it)->isSquashed()) {
1623            if (!(*inst_list_it)->isIssued()) {
1624                ++valid_num;
1625                cprintf("Count:%i\n", valid_num);
1626            } else if ((*inst_list_it)->isMemRef() &&
1627                       !(*inst_list_it)->memOpDone()) {
1628                // Loads that have not been marked as executed
1629                // still count towards the total instructions.
1630                ++valid_num;
1631                cprintf("Count:%i\n", valid_num);
1632            }
1633        }
1634
1635        cprintf("PC: %s\n[sn:%lli]\n[tid:%i]\n"
1636                "Issued:%i\nSquashed:%i\n",
1637                (*inst_list_it)->pcState(),
1638                (*inst_list_it)->seqNum,
1639                (*inst_list_it)->threadNumber,
1640                (*inst_list_it)->isIssued(),
1641                (*inst_list_it)->isSquashed());
1642
1643        if ((*inst_list_it)->isMemRef()) {
1644            cprintf("MemOpDone:%i\n", (*inst_list_it)->memOpDone());
1645        }
1646
1647        cprintf("\n");
1648
1649        inst_list_it++;
1650        ++num;
1651    }
1652}
1653
1654#endif//__CPU_O3_INST_QUEUE_IMPL_HH__
1655