1/*
2 * Copyright (c) 2004-2006 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Kevin Lim
29 * Korey Sewell
30 */
31
32#ifndef __CPU_O3_LSQ_UNIT_HH__
33#define __CPU_O3_LSQ_UNIT_HH__
34
35#include <algorithm>
| 1/*
2 * Copyright (c) 2004-2006 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Kevin Lim
29 * Korey Sewell
30 */
31
32#ifndef __CPU_O3_LSQ_UNIT_HH__
33#define __CPU_O3_LSQ_UNIT_HH__
34
35#include <algorithm>
|
36#include <map>
37#include <queue>
38
39#include "arch/faults.hh"
40#include "arch/locked_mem.hh"
41#include "config/full_system.hh"
42#include "base/hashmap.hh"
43#include "cpu/inst_seq.hh"
44#include "mem/packet.hh"
45#include "mem/port.hh"
46
47/**
48 * Class that implements the actual LQ and SQ for each specific
49 * thread. Both are circular queues; load entries are freed upon
50 * committing, while store entries are freed once they writeback. The
51 * LSQUnit tracks if there are memory ordering violations, and also
52 * detects partial load to store forwarding cases (a store only has
53 * part of a load's data) that requires the load to wait until the
54 * store writes back. In the former case it holds onto the instruction
55 * until the dependence unit looks at it, and in the latter it stalls
56 * the LSQ until the store writes back. At that point the load is
57 * replayed.
58 */
59template <class Impl>
60class LSQUnit {
61 protected:
62 typedef TheISA::IntReg IntReg;
63 public:
64 typedef typename Impl::Params Params;
65 typedef typename Impl::O3CPU O3CPU;
66 typedef typename Impl::DynInstPtr DynInstPtr;
67 typedef typename Impl::CPUPol::IEW IEW;
68 typedef typename Impl::CPUPol::LSQ LSQ;
69 typedef typename Impl::CPUPol::IssueStruct IssueStruct;
70
71 public:
72 /** Constructs an LSQ unit. init() must be called prior to use. */
73 LSQUnit();
74
75 /** Initializes the LSQ unit with the specified number of entries. */
76 void init(O3CPU *cpu_ptr, IEW *iew_ptr, Params *params, LSQ *lsq_ptr,
77 unsigned maxLQEntries, unsigned maxSQEntries, unsigned id);
78
79 /** Returns the name of the LSQ unit. */
80 std::string name() const;
81
82 /** Registers statistics. */
83 void regStats();
84
85 /** Sets the pointer to the dcache port. */
86 void setDcachePort(Port *dcache_port);
87
88 /** Switches out LSQ unit. */
89 void switchOut();
90
91 /** Takes over from another CPU's thread. */
92 void takeOverFrom();
93
94 /** Returns if the LSQ is switched out. */
95 bool isSwitchedOut() { return switchedOut; }
96
97 /** Ticks the LSQ unit, which in this case only resets the number of
98 * used cache ports.
99 * @todo: Move the number of used ports up to the LSQ level so it can
100 * be shared by all LSQ units.
101 */
102 void tick() { usedPorts = 0; }
103
104 /** Inserts an instruction. */
105 void insert(DynInstPtr &inst);
106 /** Inserts a load instruction. */
107 void insertLoad(DynInstPtr &load_inst);
108 /** Inserts a store instruction. */
109 void insertStore(DynInstPtr &store_inst);
110
111 /** Executes a load instruction. */
112 Fault executeLoad(DynInstPtr &inst);
113
114 Fault executeLoad(int lq_idx) { panic("Not implemented"); return NoFault; }
115 /** Executes a store instruction. */
116 Fault executeStore(DynInstPtr &inst);
117
118 /** Commits the head load. */
119 void commitLoad();
120 /** Commits loads older than a specific sequence number. */
121 void commitLoads(InstSeqNum &youngest_inst);
122
123 /** Commits stores older than a specific sequence number. */
124 void commitStores(InstSeqNum &youngest_inst);
125
126 /** Writes back stores. */
127 void writebackStores();
128
129 /** Completes the data access that has been returned from the
130 * memory system. */
131 void completeDataAccess(PacketPtr pkt);
132
133 /** Clears all the entries in the LQ. */
134 void clearLQ();
135
136 /** Clears all the entries in the SQ. */
137 void clearSQ();
138
139 /** Resizes the LQ to a given size. */
140 void resizeLQ(unsigned size);
141
142 /** Resizes the SQ to a given size. */
143 void resizeSQ(unsigned size);
144
145 /** Squashes all instructions younger than a specific sequence number. */
146 void squash(const InstSeqNum &squashed_num);
147
148 /** Returns if there is a memory ordering violation. Value is reset upon
149 * call to getMemDepViolator().
150 */
151 bool violation() { return memDepViolator; }
152
153 /** Returns the memory ordering violator. */
154 DynInstPtr getMemDepViolator();
155
156 /** Returns if a load became blocked due to the memory system. */
157 bool loadBlocked()
158 { return isLoadBlocked; }
159
160 /** Clears the signal that a load became blocked. */
161 void clearLoadBlocked()
162 { isLoadBlocked = false; }
163
164 /** Returns if the blocked load was handled. */
165 bool isLoadBlockedHandled()
166 { return loadBlockedHandled; }
167
168 /** Records the blocked load as being handled. */
169 void setLoadBlockedHandled()
170 { loadBlockedHandled = true; }
171
172 /** Returns the number of free entries (min of free LQ and SQ entries). */
173 unsigned numFreeEntries();
174
175 /** Returns the number of loads ready to execute. */
176 int numLoadsReady();
177
178 /** Returns the number of loads in the LQ. */
179 int numLoads() { return loads; }
180
181 /** Returns the number of stores in the SQ. */
182 int numStores() { return stores; }
183
184 /** Returns if either the LQ or SQ is full. */
185 bool isFull() { return lqFull() || sqFull(); }
186
187 /** Returns if the LQ is full. */
188 bool lqFull() { return loads >= (LQEntries - 1); }
189
190 /** Returns if the SQ is full. */
191 bool sqFull() { return stores >= (SQEntries - 1); }
192
193 /** Returns the number of instructions in the LSQ. */
194 unsigned getCount() { return loads + stores; }
195
196 /** Returns if there are any stores to writeback. */
197 bool hasStoresToWB() { return storesToWB; }
198
199 /** Returns the number of stores to writeback. */
200 int numStoresToWB() { return storesToWB; }
201
202 /** Returns if the LSQ unit will writeback on this cycle. */
203 bool willWB() { return storeQueue[storeWBIdx].canWB &&
204 !storeQueue[storeWBIdx].completed &&
205 !isStoreBlocked; }
206
207 /** Handles doing the retry. */
208 void recvRetry();
209
210 private:
211 /** Writes back the instruction, sending it to IEW. */
212 void writeback(DynInstPtr &inst, PacketPtr pkt);
213
214 /** Handles completing the send of a store to memory. */
215 void storePostSend(PacketPtr pkt);
216
217 /** Completes the store at the specified index. */
218 void completeStore(int store_idx);
219
220 /** Increments the given store index (circular queue). */
221 inline void incrStIdx(int &store_idx);
222 /** Decrements the given store index (circular queue). */
223 inline void decrStIdx(int &store_idx);
224 /** Increments the given load index (circular queue). */
225 inline void incrLdIdx(int &load_idx);
226 /** Decrements the given load index (circular queue). */
227 inline void decrLdIdx(int &load_idx);
228
229 public:
230 /** Debugging function to dump instructions in the LSQ. */
231 void dumpInsts();
232
233 private:
234 /** Pointer to the CPU. */
235 O3CPU *cpu;
236
237 /** Pointer to the IEW stage. */
238 IEW *iewStage;
239
240 /** Pointer to the LSQ. */
241 LSQ *lsq;
242
243 /** Pointer to the dcache port. Used only for sending. */
244 Port *dcachePort;
245
246 /** Derived class to hold any sender state the LSQ needs. */
247 class LSQSenderState : public Packet::SenderState
248 {
249 public:
250 /** Default constructor. */
251 LSQSenderState()
252 : noWB(false)
253 { }
254
255 /** Instruction who initiated the access to memory. */
256 DynInstPtr inst;
257 /** Whether or not it is a load. */
258 bool isLoad;
259 /** The LQ/SQ index of the instruction. */
260 int idx;
261 /** Whether or not the instruction will need to writeback. */
262 bool noWB;
263 };
264
265 /** Writeback event, specifically for when stores forward data to loads. */
266 class WritebackEvent : public Event {
267 public:
268 /** Constructs a writeback event. */
269 WritebackEvent(DynInstPtr &_inst, PacketPtr pkt, LSQUnit *lsq_ptr);
270
271 /** Processes the writeback event. */
272 void process();
273
274 /** Returns the description of this event. */
275 const char *description();
276
277 private:
278 /** Instruction whose results are being written back. */
279 DynInstPtr inst;
280
281 /** The packet that would have been sent to memory. */
282 PacketPtr pkt;
283
284 /** The pointer to the LSQ unit that issued the store. */
285 LSQUnit<Impl> *lsqPtr;
286 };
287
288 public:
289 struct SQEntry {
290 /** Constructs an empty store queue entry. */
291 SQEntry()
292 : inst(NULL), req(NULL), size(0),
293 canWB(0), committed(0), completed(0)
294 {
| 37#include <map>
38#include <queue>
39
40#include "arch/faults.hh"
41#include "arch/locked_mem.hh"
42#include "config/full_system.hh"
43#include "base/hashmap.hh"
44#include "cpu/inst_seq.hh"
45#include "mem/packet.hh"
46#include "mem/port.hh"
47
48/**
49 * Class that implements the actual LQ and SQ for each specific
50 * thread. Both are circular queues; load entries are freed upon
51 * committing, while store entries are freed once they writeback. The
52 * LSQUnit tracks if there are memory ordering violations, and also
53 * detects partial load to store forwarding cases (a store only has
54 * part of a load's data) that requires the load to wait until the
55 * store writes back. In the former case it holds onto the instruction
56 * until the dependence unit looks at it, and in the latter it stalls
57 * the LSQ until the store writes back. At that point the load is
58 * replayed.
59 */
60template <class Impl>
61class LSQUnit {
62 protected:
63 typedef TheISA::IntReg IntReg;
64 public:
65 typedef typename Impl::Params Params;
66 typedef typename Impl::O3CPU O3CPU;
67 typedef typename Impl::DynInstPtr DynInstPtr;
68 typedef typename Impl::CPUPol::IEW IEW;
69 typedef typename Impl::CPUPol::LSQ LSQ;
70 typedef typename Impl::CPUPol::IssueStruct IssueStruct;
71
72 public:
73 /** Constructs an LSQ unit. init() must be called prior to use. */
74 LSQUnit();
75
76 /** Initializes the LSQ unit with the specified number of entries. */
77 void init(O3CPU *cpu_ptr, IEW *iew_ptr, Params *params, LSQ *lsq_ptr,
78 unsigned maxLQEntries, unsigned maxSQEntries, unsigned id);
79
80 /** Returns the name of the LSQ unit. */
81 std::string name() const;
82
83 /** Registers statistics. */
84 void regStats();
85
86 /** Sets the pointer to the dcache port. */
87 void setDcachePort(Port *dcache_port);
88
89 /** Switches out LSQ unit. */
90 void switchOut();
91
92 /** Takes over from another CPU's thread. */
93 void takeOverFrom();
94
95 /** Returns if the LSQ is switched out. */
96 bool isSwitchedOut() { return switchedOut; }
97
98 /** Ticks the LSQ unit, which in this case only resets the number of
99 * used cache ports.
100 * @todo: Move the number of used ports up to the LSQ level so it can
101 * be shared by all LSQ units.
102 */
103 void tick() { usedPorts = 0; }
104
105 /** Inserts an instruction. */
106 void insert(DynInstPtr &inst);
107 /** Inserts a load instruction. */
108 void insertLoad(DynInstPtr &load_inst);
109 /** Inserts a store instruction. */
110 void insertStore(DynInstPtr &store_inst);
111
112 /** Executes a load instruction. */
113 Fault executeLoad(DynInstPtr &inst);
114
115 Fault executeLoad(int lq_idx) { panic("Not implemented"); return NoFault; }
116 /** Executes a store instruction. */
117 Fault executeStore(DynInstPtr &inst);
118
119 /** Commits the head load. */
120 void commitLoad();
121 /** Commits loads older than a specific sequence number. */
122 void commitLoads(InstSeqNum &youngest_inst);
123
124 /** Commits stores older than a specific sequence number. */
125 void commitStores(InstSeqNum &youngest_inst);
126
127 /** Writes back stores. */
128 void writebackStores();
129
130 /** Completes the data access that has been returned from the
131 * memory system. */
132 void completeDataAccess(PacketPtr pkt);
133
134 /** Clears all the entries in the LQ. */
135 void clearLQ();
136
137 /** Clears all the entries in the SQ. */
138 void clearSQ();
139
140 /** Resizes the LQ to a given size. */
141 void resizeLQ(unsigned size);
142
143 /** Resizes the SQ to a given size. */
144 void resizeSQ(unsigned size);
145
146 /** Squashes all instructions younger than a specific sequence number. */
147 void squash(const InstSeqNum &squashed_num);
148
149 /** Returns if there is a memory ordering violation. Value is reset upon
150 * call to getMemDepViolator().
151 */
152 bool violation() { return memDepViolator; }
153
154 /** Returns the memory ordering violator. */
155 DynInstPtr getMemDepViolator();
156
157 /** Returns if a load became blocked due to the memory system. */
158 bool loadBlocked()
159 { return isLoadBlocked; }
160
161 /** Clears the signal that a load became blocked. */
162 void clearLoadBlocked()
163 { isLoadBlocked = false; }
164
165 /** Returns if the blocked load was handled. */
166 bool isLoadBlockedHandled()
167 { return loadBlockedHandled; }
168
169 /** Records the blocked load as being handled. */
170 void setLoadBlockedHandled()
171 { loadBlockedHandled = true; }
172
173 /** Returns the number of free entries (min of free LQ and SQ entries). */
174 unsigned numFreeEntries();
175
176 /** Returns the number of loads ready to execute. */
177 int numLoadsReady();
178
179 /** Returns the number of loads in the LQ. */
180 int numLoads() { return loads; }
181
182 /** Returns the number of stores in the SQ. */
183 int numStores() { return stores; }
184
185 /** Returns if either the LQ or SQ is full. */
186 bool isFull() { return lqFull() || sqFull(); }
187
188 /** Returns if the LQ is full. */
189 bool lqFull() { return loads >= (LQEntries - 1); }
190
191 /** Returns if the SQ is full. */
192 bool sqFull() { return stores >= (SQEntries - 1); }
193
194 /** Returns the number of instructions in the LSQ. */
195 unsigned getCount() { return loads + stores; }
196
197 /** Returns if there are any stores to writeback. */
198 bool hasStoresToWB() { return storesToWB; }
199
200 /** Returns the number of stores to writeback. */
201 int numStoresToWB() { return storesToWB; }
202
203 /** Returns if the LSQ unit will writeback on this cycle. */
204 bool willWB() { return storeQueue[storeWBIdx].canWB &&
205 !storeQueue[storeWBIdx].completed &&
206 !isStoreBlocked; }
207
208 /** Handles doing the retry. */
209 void recvRetry();
210
211 private:
212 /** Writes back the instruction, sending it to IEW. */
213 void writeback(DynInstPtr &inst, PacketPtr pkt);
214
215 /** Handles completing the send of a store to memory. */
216 void storePostSend(PacketPtr pkt);
217
218 /** Completes the store at the specified index. */
219 void completeStore(int store_idx);
220
221 /** Increments the given store index (circular queue). */
222 inline void incrStIdx(int &store_idx);
223 /** Decrements the given store index (circular queue). */
224 inline void decrStIdx(int &store_idx);
225 /** Increments the given load index (circular queue). */
226 inline void incrLdIdx(int &load_idx);
227 /** Decrements the given load index (circular queue). */
228 inline void decrLdIdx(int &load_idx);
229
230 public:
231 /** Debugging function to dump instructions in the LSQ. */
232 void dumpInsts();
233
234 private:
235 /** Pointer to the CPU. */
236 O3CPU *cpu;
237
238 /** Pointer to the IEW stage. */
239 IEW *iewStage;
240
241 /** Pointer to the LSQ. */
242 LSQ *lsq;
243
244 /** Pointer to the dcache port. Used only for sending. */
245 Port *dcachePort;
246
247 /** Derived class to hold any sender state the LSQ needs. */
248 class LSQSenderState : public Packet::SenderState
249 {
250 public:
251 /** Default constructor. */
252 LSQSenderState()
253 : noWB(false)
254 { }
255
256 /** Instruction who initiated the access to memory. */
257 DynInstPtr inst;
258 /** Whether or not it is a load. */
259 bool isLoad;
260 /** The LQ/SQ index of the instruction. */
261 int idx;
262 /** Whether or not the instruction will need to writeback. */
263 bool noWB;
264 };
265
266 /** Writeback event, specifically for when stores forward data to loads. */
267 class WritebackEvent : public Event {
268 public:
269 /** Constructs a writeback event. */
270 WritebackEvent(DynInstPtr &_inst, PacketPtr pkt, LSQUnit *lsq_ptr);
271
272 /** Processes the writeback event. */
273 void process();
274
275 /** Returns the description of this event. */
276 const char *description();
277
278 private:
279 /** Instruction whose results are being written back. */
280 DynInstPtr inst;
281
282 /** The packet that would have been sent to memory. */
283 PacketPtr pkt;
284
285 /** The pointer to the LSQ unit that issued the store. */
286 LSQUnit<Impl> *lsqPtr;
287 };
288
289 public:
290 struct SQEntry {
291 /** Constructs an empty store queue entry. */
292 SQEntry()
293 : inst(NULL), req(NULL), size(0),
294 canWB(0), committed(0), completed(0)
295 {
|
304 }
305
306 /** The store instruction. */
307 DynInstPtr inst;
308 /** The request for the store. */
309 RequestPtr req;
310 /** The size of the store. */
311 int size;
312 /** The store data. */
313 char data[sizeof(IntReg)];
314 /** Whether or not the store can writeback. */
315 bool canWB;
316 /** Whether or not the store is committed. */
317 bool committed;
318 /** Whether or not the store is completed. */
319 bool completed;
320 };
321
322 private:
323 /** The LSQUnit thread id. */
324 unsigned lsqID;
325
326 /** The store queue. */
327 std::vector<SQEntry> storeQueue;
328
329 /** The load queue. */
330 std::vector<DynInstPtr> loadQueue;
331
332 /** The number of LQ entries, plus a sentinel entry (circular queue).
333 * @todo: Consider having var that records the true number of LQ entries.
334 */
335 unsigned LQEntries;
336 /** The number of SQ entries, plus a sentinel entry (circular queue).
337 * @todo: Consider having var that records the true number of SQ entries.
338 */
339 unsigned SQEntries;
340
341 /** The number of load instructions in the LQ. */
342 int loads;
343 /** The number of store instructions in the SQ. */
344 int stores;
345 /** The number of store instructions in the SQ waiting to writeback. */
346 int storesToWB;
347
348 /** The index of the head instruction in the LQ. */
349 int loadHead;
350 /** The index of the tail instruction in the LQ. */
351 int loadTail;
352
353 /** The index of the head instruction in the SQ. */
354 int storeHead;
355 /** The index of the first instruction that may be ready to be
356 * written back, and has not yet been written back.
357 */
358 int storeWBIdx;
359 /** The index of the tail instruction in the SQ. */
360 int storeTail;
361
362 /// @todo Consider moving to a more advanced model with write vs read ports
363 /** The number of cache ports available each cycle. */
364 int cachePorts;
365
366 /** The number of used cache ports in this cycle. */
367 int usedPorts;
368
369 /** Is the LSQ switched out. */
370 bool switchedOut;
371
372 //list<InstSeqNum> mshrSeqNums;
373
374 /** Wire to read information from the issue stage time queue. */
375 typename TimeBuffer<IssueStruct>::wire fromIssue;
376
377 /** Whether or not the LSQ is stalled. */
378 bool stalled;
379 /** The store that causes the stall due to partial store to load
380 * forwarding.
381 */
382 InstSeqNum stallingStoreIsn;
383 /** The index of the above store. */
384 int stallingLoadIdx;
385
386 /** The packet that needs to be retried. */
387 PacketPtr retryPkt;
388
389 /** Whehter or not a store is blocked due to the memory system. */
390 bool isStoreBlocked;
391
392 /** Whether or not a load is blocked due to the memory system. */
393 bool isLoadBlocked;
394
395 /** Has the blocked load been handled. */
396 bool loadBlockedHandled;
397
398 /** The sequence number of the blocked load. */
399 InstSeqNum blockedLoadSeqNum;
400
401 /** The oldest load that caused a memory ordering violation. */
402 DynInstPtr memDepViolator;
403
404 // Will also need how many read/write ports the Dcache has. Or keep track
405 // of that in stage that is one level up, and only call executeLoad/Store
406 // the appropriate number of times.
407 /** Total number of loads forwaded from LSQ stores. */
408 Stats::Scalar<> lsqForwLoads;
409
410 /** Total number of loads ignored due to invalid addresses. */
411 Stats::Scalar<> invAddrLoads;
412
413 /** Total number of squashed loads. */
414 Stats::Scalar<> lsqSquashedLoads;
415
416 /** Total number of responses from the memory system that are
417 * ignored due to the instruction already being squashed. */
418 Stats::Scalar<> lsqIgnoredResponses;
419
420 /** Tota number of memory ordering violations. */
421 Stats::Scalar<> lsqMemOrderViolation;
422
423 /** Total number of squashed stores. */
424 Stats::Scalar<> lsqSquashedStores;
425
426 /** Total number of software prefetches ignored due to invalid addresses. */
427 Stats::Scalar<> invAddrSwpfs;
428
429 /** Ready loads blocked due to partial store-forwarding. */
430 Stats::Scalar<> lsqBlockedLoads;
431
432 /** Number of loads that were rescheduled. */
433 Stats::Scalar<> lsqRescheduledLoads;
434
435 /** Number of times the LSQ is blocked due to the cache. */
436 Stats::Scalar<> lsqCacheBlocked;
437
438 public:
439 /** Executes the load at the given index. */
440 template <class T>
441 Fault read(Request *req, T &data, int load_idx);
442
443 /** Executes the store at the given index. */
444 template <class T>
445 Fault write(Request *req, T &data, int store_idx);
446
447 /** Returns the index of the head load instruction. */
448 int getLoadHead() { return loadHead; }
449 /** Returns the sequence number of the head load instruction. */
450 InstSeqNum getLoadHeadSeqNum()
451 {
452 if (loadQueue[loadHead]) {
453 return loadQueue[loadHead]->seqNum;
454 } else {
455 return 0;
456 }
457
458 }
459
460 /** Returns the index of the head store instruction. */
461 int getStoreHead() { return storeHead; }
462 /** Returns the sequence number of the head store instruction. */
463 InstSeqNum getStoreHeadSeqNum()
464 {
465 if (storeQueue[storeHead].inst) {
466 return storeQueue[storeHead].inst->seqNum;
467 } else {
468 return 0;
469 }
470
471 }
472
473 /** Returns whether or not the LSQ unit is stalled. */
474 bool isStalled() { return stalled; }
475};
476
477template <class Impl>
478template <class T>
479Fault
480LSQUnit<Impl>::read(Request *req, T &data, int load_idx)
481{
482 DynInstPtr load_inst = loadQueue[load_idx];
483
484 assert(load_inst);
485
486 assert(!load_inst->isExecuted());
487
488 // Make sure this isn't an uncacheable access
489 // A bit of a hackish way to get uncached accesses to work only if they're
490 // at the head of the LSQ and are ready to commit (at the head of the ROB
491 // too).
492 if (req->isUncacheable() &&
493 (load_idx != loadHead || !load_inst->isAtCommit())) {
494 iewStage->rescheduleMemInst(load_inst);
495 ++lsqRescheduledLoads;
496
497 // Must delete request now that it wasn't handed off to
498 // memory. This is quite ugly. @todo: Figure out the proper
499 // place to really handle request deletes.
500 delete req;
501 return TheISA::genMachineCheckFault();
502 }
503
504 // Check the SQ for any previous stores that might lead to forwarding
505 int store_idx = load_inst->sqIdx;
506
507 int store_size = 0;
508
509 DPRINTF(LSQUnit, "Read called, load idx: %i, store idx: %i, "
510 "storeHead: %i addr: %#x\n",
511 load_idx, store_idx, storeHead, req->getPaddr());
512
513 if (req->isLocked()) {
514 // Disable recording the result temporarily. Writing to misc
515 // regs normally updates the result, but this is not the
516 // desired behavior when handling store conditionals.
517 load_inst->recordResult = false;
518 TheISA::handleLockedRead(load_inst.get(), req);
519 load_inst->recordResult = true;
520 }
521
522 while (store_idx != -1) {
523 // End once we've reached the top of the LSQ
524 if (store_idx == storeWBIdx) {
525 break;
526 }
527
528 // Move the index to one younger
529 if (--store_idx < 0)
530 store_idx += SQEntries;
531
532 assert(storeQueue[store_idx].inst);
533
534 store_size = storeQueue[store_idx].size;
535
536 if (store_size == 0)
537 continue;
538 else if (storeQueue[store_idx].inst->uncacheable())
539 continue;
540
541 assert(storeQueue[store_idx].inst->effAddrValid);
542
543 // Check if the store data is within the lower and upper bounds of
544 // addresses that the request needs.
545 bool store_has_lower_limit =
546 req->getVaddr() >= storeQueue[store_idx].inst->effAddr;
547 bool store_has_upper_limit =
548 (req->getVaddr() + req->getSize()) <=
549 (storeQueue[store_idx].inst->effAddr + store_size);
550 bool lower_load_has_store_part =
551 req->getVaddr() < (storeQueue[store_idx].inst->effAddr +
552 store_size);
553 bool upper_load_has_store_part =
554 (req->getVaddr() + req->getSize()) >
555 storeQueue[store_idx].inst->effAddr;
556
557 // If the store's data has all of the data needed, we can forward.
558 if ((store_has_lower_limit && store_has_upper_limit)) {
559 // Get shift amount for offset into the store's data.
560 int shift_amt = req->getVaddr() & (store_size - 1);
561
562 memcpy(&data, storeQueue[store_idx].data + shift_amt, sizeof(T));
563
564 assert(!load_inst->memData);
565 load_inst->memData = new uint8_t[64];
566
567 memcpy(load_inst->memData,
568 storeQueue[store_idx].data + shift_amt, req->getSize());
569
570 DPRINTF(LSQUnit, "Forwarding from store idx %i to load to "
571 "addr %#x, data %#x\n",
572 store_idx, req->getVaddr(), data);
573
574 PacketPtr data_pkt = new Packet(req, MemCmd::ReadReq,
575 Packet::Broadcast);
576 data_pkt->dataStatic(load_inst->memData);
577
578 WritebackEvent *wb = new WritebackEvent(load_inst, data_pkt, this);
579
580 // We'll say this has a 1 cycle load-store forwarding latency
581 // for now.
582 // @todo: Need to make this a parameter.
583 wb->schedule(curTick);
584
585 ++lsqForwLoads;
586 return NoFault;
587 } else if ((store_has_lower_limit && lower_load_has_store_part) ||
588 (store_has_upper_limit && upper_load_has_store_part) ||
589 (lower_load_has_store_part && upper_load_has_store_part)) {
590 // This is the partial store-load forwarding case where a store
591 // has only part of the load's data.
592
593 // If it's already been written back, then don't worry about
594 // stalling on it.
595 if (storeQueue[store_idx].completed) {
596 panic("Should not check one of these");
597 continue;
598 }
599
600 // Must stall load and force it to retry, so long as it's the oldest
601 // load that needs to do so.
602 if (!stalled ||
603 (stalled &&
604 load_inst->seqNum <
605 loadQueue[stallingLoadIdx]->seqNum)) {
606 stalled = true;
607 stallingStoreIsn = storeQueue[store_idx].inst->seqNum;
608 stallingLoadIdx = load_idx;
609 }
610
611 // Tell IQ/mem dep unit that this instruction will need to be
612 // rescheduled eventually
613 iewStage->rescheduleMemInst(load_inst);
614 iewStage->decrWb(load_inst->seqNum);
615 load_inst->clearIssued();
616 ++lsqRescheduledLoads;
617
618 // Do not generate a writeback event as this instruction is not
619 // complete.
620 DPRINTF(LSQUnit, "Load-store forwarding mis-match. "
621 "Store idx %i to load addr %#x\n",
622 store_idx, req->getVaddr());
623
624 // Must delete request now that it wasn't handed off to
625 // memory. This is quite ugly. @todo: Figure out the
626 // proper place to really handle request deletes.
627 delete req;
628
629 return NoFault;
630 }
631 }
632
633 // If there's no forwarding case, then go access memory
634 DPRINTF(LSQUnit, "Doing memory access for inst [sn:%lli] PC %#x\n",
635 load_inst->seqNum, load_inst->readPC());
636
637 assert(!load_inst->memData);
638 load_inst->memData = new uint8_t[64];
639
640 ++usedPorts;
641
642 // if we the cache is not blocked, do cache access
643 if (!lsq->cacheBlocked()) {
644 PacketPtr data_pkt =
645 new Packet(req, MemCmd::ReadReq, Packet::Broadcast);
646 data_pkt->dataStatic(load_inst->memData);
647
648 LSQSenderState *state = new LSQSenderState;
649 state->isLoad = true;
650 state->idx = load_idx;
651 state->inst = load_inst;
652 data_pkt->senderState = state;
653
654 if (!dcachePort->sendTiming(data_pkt)) {
655 Packet::Result result = data_pkt->result;
656
657 // Delete state and data packet because a load retry
658 // initiates a pipeline restart; it does not retry.
659 delete state;
660 delete data_pkt->req;
661 delete data_pkt;
662
663 req = NULL;
664
665 if (result == Packet::BadAddress) {
666 return TheISA::genMachineCheckFault();
667 }
668
669 // If the access didn't succeed, tell the LSQ by setting
670 // the retry thread id.
671 lsq->setRetryTid(lsqID);
672 }
673 }
674
675 // If the cache was blocked, or has become blocked due to the access,
676 // handle it.
677 if (lsq->cacheBlocked()) {
678 if (req)
679 delete req;
680
681 ++lsqCacheBlocked;
682
683 iewStage->decrWb(load_inst->seqNum);
684 // There's an older load that's already going to squash.
685 if (isLoadBlocked && blockedLoadSeqNum < load_inst->seqNum)
686 return NoFault;
687
688 // Record that the load was blocked due to memory. This
689 // load will squash all instructions after it, be
690 // refetched, and re-executed.
691 isLoadBlocked = true;
692 loadBlockedHandled = false;
693 blockedLoadSeqNum = load_inst->seqNum;
694 // No fault occurred, even though the interface is blocked.
695 return NoFault;
696 }
697
698 return NoFault;
699}
700
701template <class Impl>
702template <class T>
703Fault
704LSQUnit<Impl>::write(Request *req, T &data, int store_idx)
705{
706 assert(storeQueue[store_idx].inst);
707
708 DPRINTF(LSQUnit, "Doing write to store idx %i, addr %#x data %#x"
709 " | storeHead:%i [sn:%i]\n",
710 store_idx, req->getPaddr(), data, storeHead,
711 storeQueue[store_idx].inst->seqNum);
712
713 storeQueue[store_idx].req = req;
714 storeQueue[store_idx].size = sizeof(T);
715 assert(sizeof(T) <= sizeof(storeQueue[store_idx].data));
716
717 T gData = htog(data);
718 memcpy(storeQueue[store_idx].data, &gData, sizeof(T));
719
720 // This function only writes the data to the store queue, so no fault
721 // can happen here.
722 return NoFault;
723}
724
725#endif // __CPU_O3_LSQ_UNIT_HH__
| 305 }
306
307 /** The store instruction. */
308 DynInstPtr inst;
309 /** The request for the store. */
310 RequestPtr req;
311 /** The size of the store. */
312 int size;
313 /** The store data. */
314 char data[sizeof(IntReg)];
315 /** Whether or not the store can writeback. */
316 bool canWB;
317 /** Whether or not the store is committed. */
318 bool committed;
319 /** Whether or not the store is completed. */
320 bool completed;
321 };
322
323 private:
324 /** The LSQUnit thread id. */
325 unsigned lsqID;
326
327 /** The store queue. */
328 std::vector<SQEntry> storeQueue;
329
330 /** The load queue. */
331 std::vector<DynInstPtr> loadQueue;
332
333 /** The number of LQ entries, plus a sentinel entry (circular queue).
334 * @todo: Consider having var that records the true number of LQ entries.
335 */
336 unsigned LQEntries;
337 /** The number of SQ entries, plus a sentinel entry (circular queue).
338 * @todo: Consider having var that records the true number of SQ entries.
339 */
340 unsigned SQEntries;
341
342 /** The number of load instructions in the LQ. */
343 int loads;
344 /** The number of store instructions in the SQ. */
345 int stores;
346 /** The number of store instructions in the SQ waiting to writeback. */
347 int storesToWB;
348
349 /** The index of the head instruction in the LQ. */
350 int loadHead;
351 /** The index of the tail instruction in the LQ. */
352 int loadTail;
353
354 /** The index of the head instruction in the SQ. */
355 int storeHead;
356 /** The index of the first instruction that may be ready to be
357 * written back, and has not yet been written back.
358 */
359 int storeWBIdx;
360 /** The index of the tail instruction in the SQ. */
361 int storeTail;
362
363 /// @todo Consider moving to a more advanced model with write vs read ports
364 /** The number of cache ports available each cycle. */
365 int cachePorts;
366
367 /** The number of used cache ports in this cycle. */
368 int usedPorts;
369
370 /** Is the LSQ switched out. */
371 bool switchedOut;
372
373 //list<InstSeqNum> mshrSeqNums;
374
375 /** Wire to read information from the issue stage time queue. */
376 typename TimeBuffer<IssueStruct>::wire fromIssue;
377
378 /** Whether or not the LSQ is stalled. */
379 bool stalled;
380 /** The store that causes the stall due to partial store to load
381 * forwarding.
382 */
383 InstSeqNum stallingStoreIsn;
384 /** The index of the above store. */
385 int stallingLoadIdx;
386
387 /** The packet that needs to be retried. */
388 PacketPtr retryPkt;
389
390 /** Whehter or not a store is blocked due to the memory system. */
391 bool isStoreBlocked;
392
393 /** Whether or not a load is blocked due to the memory system. */
394 bool isLoadBlocked;
395
396 /** Has the blocked load been handled. */
397 bool loadBlockedHandled;
398
399 /** The sequence number of the blocked load. */
400 InstSeqNum blockedLoadSeqNum;
401
402 /** The oldest load that caused a memory ordering violation. */
403 DynInstPtr memDepViolator;
404
405 // Will also need how many read/write ports the Dcache has. Or keep track
406 // of that in stage that is one level up, and only call executeLoad/Store
407 // the appropriate number of times.
408 /** Total number of loads forwaded from LSQ stores. */
409 Stats::Scalar<> lsqForwLoads;
410
411 /** Total number of loads ignored due to invalid addresses. */
412 Stats::Scalar<> invAddrLoads;
413
414 /** Total number of squashed loads. */
415 Stats::Scalar<> lsqSquashedLoads;
416
417 /** Total number of responses from the memory system that are
418 * ignored due to the instruction already being squashed. */
419 Stats::Scalar<> lsqIgnoredResponses;
420
421 /** Tota number of memory ordering violations. */
422 Stats::Scalar<> lsqMemOrderViolation;
423
424 /** Total number of squashed stores. */
425 Stats::Scalar<> lsqSquashedStores;
426
427 /** Total number of software prefetches ignored due to invalid addresses. */
428 Stats::Scalar<> invAddrSwpfs;
429
430 /** Ready loads blocked due to partial store-forwarding. */
431 Stats::Scalar<> lsqBlockedLoads;
432
433 /** Number of loads that were rescheduled. */
434 Stats::Scalar<> lsqRescheduledLoads;
435
436 /** Number of times the LSQ is blocked due to the cache. */
437 Stats::Scalar<> lsqCacheBlocked;
438
439 public:
440 /** Executes the load at the given index. */
441 template <class T>
442 Fault read(Request *req, T &data, int load_idx);
443
444 /** Executes the store at the given index. */
445 template <class T>
446 Fault write(Request *req, T &data, int store_idx);
447
448 /** Returns the index of the head load instruction. */
449 int getLoadHead() { return loadHead; }
450 /** Returns the sequence number of the head load instruction. */
451 InstSeqNum getLoadHeadSeqNum()
452 {
453 if (loadQueue[loadHead]) {
454 return loadQueue[loadHead]->seqNum;
455 } else {
456 return 0;
457 }
458
459 }
460
461 /** Returns the index of the head store instruction. */
462 int getStoreHead() { return storeHead; }
463 /** Returns the sequence number of the head store instruction. */
464 InstSeqNum getStoreHeadSeqNum()
465 {
466 if (storeQueue[storeHead].inst) {
467 return storeQueue[storeHead].inst->seqNum;
468 } else {
469 return 0;
470 }
471
472 }
473
474 /** Returns whether or not the LSQ unit is stalled. */
475 bool isStalled() { return stalled; }
476};
477
478template <class Impl>
479template <class T>
480Fault
481LSQUnit<Impl>::read(Request *req, T &data, int load_idx)
482{
483 DynInstPtr load_inst = loadQueue[load_idx];
484
485 assert(load_inst);
486
487 assert(!load_inst->isExecuted());
488
489 // Make sure this isn't an uncacheable access
490 // A bit of a hackish way to get uncached accesses to work only if they're
491 // at the head of the LSQ and are ready to commit (at the head of the ROB
492 // too).
493 if (req->isUncacheable() &&
494 (load_idx != loadHead || !load_inst->isAtCommit())) {
495 iewStage->rescheduleMemInst(load_inst);
496 ++lsqRescheduledLoads;
497
498 // Must delete request now that it wasn't handed off to
499 // memory. This is quite ugly. @todo: Figure out the proper
500 // place to really handle request deletes.
501 delete req;
502 return TheISA::genMachineCheckFault();
503 }
504
505 // Check the SQ for any previous stores that might lead to forwarding
506 int store_idx = load_inst->sqIdx;
507
508 int store_size = 0;
509
510 DPRINTF(LSQUnit, "Read called, load idx: %i, store idx: %i, "
511 "storeHead: %i addr: %#x\n",
512 load_idx, store_idx, storeHead, req->getPaddr());
513
514 if (req->isLocked()) {
515 // Disable recording the result temporarily. Writing to misc
516 // regs normally updates the result, but this is not the
517 // desired behavior when handling store conditionals.
518 load_inst->recordResult = false;
519 TheISA::handleLockedRead(load_inst.get(), req);
520 load_inst->recordResult = true;
521 }
522
523 while (store_idx != -1) {
524 // End once we've reached the top of the LSQ
525 if (store_idx == storeWBIdx) {
526 break;
527 }
528
529 // Move the index to one younger
530 if (--store_idx < 0)
531 store_idx += SQEntries;
532
533 assert(storeQueue[store_idx].inst);
534
535 store_size = storeQueue[store_idx].size;
536
537 if (store_size == 0)
538 continue;
539 else if (storeQueue[store_idx].inst->uncacheable())
540 continue;
541
542 assert(storeQueue[store_idx].inst->effAddrValid);
543
544 // Check if the store data is within the lower and upper bounds of
545 // addresses that the request needs.
546 bool store_has_lower_limit =
547 req->getVaddr() >= storeQueue[store_idx].inst->effAddr;
548 bool store_has_upper_limit =
549 (req->getVaddr() + req->getSize()) <=
550 (storeQueue[store_idx].inst->effAddr + store_size);
551 bool lower_load_has_store_part =
552 req->getVaddr() < (storeQueue[store_idx].inst->effAddr +
553 store_size);
554 bool upper_load_has_store_part =
555 (req->getVaddr() + req->getSize()) >
556 storeQueue[store_idx].inst->effAddr;
557
558 // If the store's data has all of the data needed, we can forward.
559 if ((store_has_lower_limit && store_has_upper_limit)) {
560 // Get shift amount for offset into the store's data.
561 int shift_amt = req->getVaddr() & (store_size - 1);
562
563 memcpy(&data, storeQueue[store_idx].data + shift_amt, sizeof(T));
564
565 assert(!load_inst->memData);
566 load_inst->memData = new uint8_t[64];
567
568 memcpy(load_inst->memData,
569 storeQueue[store_idx].data + shift_amt, req->getSize());
570
571 DPRINTF(LSQUnit, "Forwarding from store idx %i to load to "
572 "addr %#x, data %#x\n",
573 store_idx, req->getVaddr(), data);
574
575 PacketPtr data_pkt = new Packet(req, MemCmd::ReadReq,
576 Packet::Broadcast);
577 data_pkt->dataStatic(load_inst->memData);
578
579 WritebackEvent *wb = new WritebackEvent(load_inst, data_pkt, this);
580
581 // We'll say this has a 1 cycle load-store forwarding latency
582 // for now.
583 // @todo: Need to make this a parameter.
584 wb->schedule(curTick);
585
586 ++lsqForwLoads;
587 return NoFault;
588 } else if ((store_has_lower_limit && lower_load_has_store_part) ||
589 (store_has_upper_limit && upper_load_has_store_part) ||
590 (lower_load_has_store_part && upper_load_has_store_part)) {
591 // This is the partial store-load forwarding case where a store
592 // has only part of the load's data.
593
594 // If it's already been written back, then don't worry about
595 // stalling on it.
596 if (storeQueue[store_idx].completed) {
597 panic("Should not check one of these");
598 continue;
599 }
600
601 // Must stall load and force it to retry, so long as it's the oldest
602 // load that needs to do so.
603 if (!stalled ||
604 (stalled &&
605 load_inst->seqNum <
606 loadQueue[stallingLoadIdx]->seqNum)) {
607 stalled = true;
608 stallingStoreIsn = storeQueue[store_idx].inst->seqNum;
609 stallingLoadIdx = load_idx;
610 }
611
612 // Tell IQ/mem dep unit that this instruction will need to be
613 // rescheduled eventually
614 iewStage->rescheduleMemInst(load_inst);
615 iewStage->decrWb(load_inst->seqNum);
616 load_inst->clearIssued();
617 ++lsqRescheduledLoads;
618
619 // Do not generate a writeback event as this instruction is not
620 // complete.
621 DPRINTF(LSQUnit, "Load-store forwarding mis-match. "
622 "Store idx %i to load addr %#x\n",
623 store_idx, req->getVaddr());
624
625 // Must delete request now that it wasn't handed off to
626 // memory. This is quite ugly. @todo: Figure out the
627 // proper place to really handle request deletes.
628 delete req;
629
630 return NoFault;
631 }
632 }
633
634 // If there's no forwarding case, then go access memory
635 DPRINTF(LSQUnit, "Doing memory access for inst [sn:%lli] PC %#x\n",
636 load_inst->seqNum, load_inst->readPC());
637
638 assert(!load_inst->memData);
639 load_inst->memData = new uint8_t[64];
640
641 ++usedPorts;
642
643 // if we the cache is not blocked, do cache access
644 if (!lsq->cacheBlocked()) {
645 PacketPtr data_pkt =
646 new Packet(req, MemCmd::ReadReq, Packet::Broadcast);
647 data_pkt->dataStatic(load_inst->memData);
648
649 LSQSenderState *state = new LSQSenderState;
650 state->isLoad = true;
651 state->idx = load_idx;
652 state->inst = load_inst;
653 data_pkt->senderState = state;
654
655 if (!dcachePort->sendTiming(data_pkt)) {
656 Packet::Result result = data_pkt->result;
657
658 // Delete state and data packet because a load retry
659 // initiates a pipeline restart; it does not retry.
660 delete state;
661 delete data_pkt->req;
662 delete data_pkt;
663
664 req = NULL;
665
666 if (result == Packet::BadAddress) {
667 return TheISA::genMachineCheckFault();
668 }
669
670 // If the access didn't succeed, tell the LSQ by setting
671 // the retry thread id.
672 lsq->setRetryTid(lsqID);
673 }
674 }
675
676 // If the cache was blocked, or has become blocked due to the access,
677 // handle it.
678 if (lsq->cacheBlocked()) {
679 if (req)
680 delete req;
681
682 ++lsqCacheBlocked;
683
684 iewStage->decrWb(load_inst->seqNum);
685 // There's an older load that's already going to squash.
686 if (isLoadBlocked && blockedLoadSeqNum < load_inst->seqNum)
687 return NoFault;
688
689 // Record that the load was blocked due to memory. This
690 // load will squash all instructions after it, be
691 // refetched, and re-executed.
692 isLoadBlocked = true;
693 loadBlockedHandled = false;
694 blockedLoadSeqNum = load_inst->seqNum;
695 // No fault occurred, even though the interface is blocked.
696 return NoFault;
697 }
698
699 return NoFault;
700}
701
702template <class Impl>
703template <class T>
704Fault
705LSQUnit<Impl>::write(Request *req, T &data, int store_idx)
706{
707 assert(storeQueue[store_idx].inst);
708
709 DPRINTF(LSQUnit, "Doing write to store idx %i, addr %#x data %#x"
710 " | storeHead:%i [sn:%i]\n",
711 store_idx, req->getPaddr(), data, storeHead,
712 storeQueue[store_idx].inst->seqNum);
713
714 storeQueue[store_idx].req = req;
715 storeQueue[store_idx].size = sizeof(T);
716 assert(sizeof(T) <= sizeof(storeQueue[store_idx].data));
717
718 T gData = htog(data);
719 memcpy(storeQueue[store_idx].data, &gData, sizeof(T));
720
721 // This function only writes the data to the store queue, so no fault
722 // can happen here.
723 return NoFault;
724}
725
726#endif // __CPU_O3_LSQ_UNIT_HH__
|