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 */
30
31#include "base/intmath.hh"
32#include "base/trace.hh"
33#include "cpu/o3/store_set.hh"
34
35StoreSet::StoreSet(int _SSIT_size, int _LFST_size)
36 : SSITSize(_SSIT_size), LFSTSize(_LFST_size)
37{
38 DPRINTF(StoreSet, "StoreSet: Creating store set object.\n");
39 DPRINTF(StoreSet, "StoreSet: SSIT size: %i, LFST size: %i.\n",
40 SSITSize, LFSTSize);
41
42 if (!isPowerOf2(SSITSize)) {
43 fatal("Invalid SSIT size!\n");
44 }
45
46 SSIT.resize(SSITSize);
47
48 validSSIT.resize(SSITSize);
49
50 for (int i = 0; i < SSITSize; ++i)
51 validSSIT[i] = false;
52
53 if (!isPowerOf2(LFSTSize)) {
54 fatal("Invalid LFST size!\n");
55 }
56
57 LFST.resize(LFSTSize);
58
59 validLFST.resize(LFSTSize);
60
61 for (int i = 0; i < LFSTSize; ++i) {
62 validLFST[i] = false;
63 LFST[i] = 0;
64 }
65
66 indexMask = SSITSize - 1;
67
68 offsetBits = 2;
69}
70
71StoreSet::~StoreSet()
72{
73}
74
75void
76StoreSet::init(int _SSIT_size, int _LFST_size)
77{
78 SSITSize = _SSIT_size;
79 LFSTSize = _LFST_size;
80
81 DPRINTF(StoreSet, "StoreSet: Creating store set object.\n");
82 DPRINTF(StoreSet, "StoreSet: SSIT size: %i, LFST size: %i.\n",
83 SSITSize, LFSTSize);
84
85 SSIT.resize(SSITSize);
86
87 validSSIT.resize(SSITSize);
88
89 for (int i = 0; i < SSITSize; ++i)
90 validSSIT[i] = false;
91
92 LFST.resize(LFSTSize);
93
94 validLFST.resize(LFSTSize);
95
96 for (int i = 0; i < LFSTSize; ++i) {
97 validLFST[i] = false;
98 LFST[i] = 0;
99 }
100
101 indexMask = SSITSize - 1;
102
103 offsetBits = 2;
104}
105
106
107void
108StoreSet::violation(Addr store_PC, Addr load_PC)
109{
110 int load_index = calcIndex(load_PC);
111 int store_index = calcIndex(store_PC);
112
113 assert(load_index < SSITSize && store_index < SSITSize);
114
115 bool valid_load_SSID = validSSIT[load_index];
116 bool valid_store_SSID = validSSIT[store_index];
117
118 if (!valid_load_SSID && !valid_store_SSID) {
119 // Calculate a new SSID here.
120 SSID new_set = calcSSID(load_PC);
121
122 validSSIT[load_index] = true;
123
124 SSIT[load_index] = new_set;
125
126 validSSIT[store_index] = true;
127
128 SSIT[store_index] = new_set;
129
130 assert(new_set < LFSTSize);
131
132 DPRINTF(StoreSet, "StoreSet: Neither load nor store had a valid "
133 "storeset, creating a new one: %i for load %#x, store %#x\n",
134 new_set, load_PC, store_PC);
135 } else if (valid_load_SSID && !valid_store_SSID) {
136 SSID load_SSID = SSIT[load_index];
137
138 validSSIT[store_index] = true;
139
140 SSIT[store_index] = load_SSID;
141
142 assert(load_SSID < LFSTSize);
143
144 DPRINTF(StoreSet, "StoreSet: Load had a valid store set. Adding "
145 "store to that set: %i for load %#x, store %#x\n",
146 load_SSID, load_PC, store_PC);
147 } else if (!valid_load_SSID && valid_store_SSID) {
148 SSID store_SSID = SSIT[store_index];
149
150 validSSIT[load_index] = true;
151
152 SSIT[load_index] = store_SSID;
153
154 DPRINTF(StoreSet, "StoreSet: Store had a valid store set: %i for "
155 "load %#x, store %#x\n",
156 store_SSID, load_PC, store_PC);
157 } else {
158 SSID load_SSID = SSIT[load_index];
159 SSID store_SSID = SSIT[store_index];
160
161 assert(load_SSID < LFSTSize && store_SSID < LFSTSize);
162
163 // The store set with the lower number wins
164 if (store_SSID > load_SSID) {
165 SSIT[store_index] = load_SSID;
166
167 DPRINTF(StoreSet, "StoreSet: Load had smaller store set: %i; "
168 "for load %#x, store %#x\n",
169 load_SSID, load_PC, store_PC);
170 } else {
171 SSIT[load_index] = store_SSID;
172
173 DPRINTF(StoreSet, "StoreSet: Store had smaller store set: %i; "
174 "for load %#x, store %#x\n",
175 store_SSID, load_PC, store_PC);
176 }
177 }
178}
179
180void
181StoreSet::insertLoad(Addr load_PC, InstSeqNum load_seq_num)
182{
183 // Does nothing.
184 return;
185}
186
187void
188StoreSet::insertStore(Addr store_PC, InstSeqNum store_seq_num,
189 unsigned tid)
190{
191 int index = calcIndex(store_PC);
192
193 int store_SSID;
194
195 assert(index < SSITSize);
196
197 if (!validSSIT[index]) {
198 // Do nothing if there's no valid entry.
199 return;
200 } else {
201 store_SSID = SSIT[index];
202
203 assert(store_SSID < LFSTSize);
204
205 // Update the last store that was fetched with the current one.
206 LFST[store_SSID] = store_seq_num;
207
208 validLFST[store_SSID] = 1;
209
210 storeList[store_seq_num] = store_SSID;
211
212 DPRINTF(StoreSet, "Store %#x updated the LFST, SSID: %i\n",
213 store_PC, store_SSID);
214 }
215}
216
217InstSeqNum
218StoreSet::checkInst(Addr PC)
219{
220 int index = calcIndex(PC);
221
222 int inst_SSID;
223
224 assert(index < SSITSize);
225
226 if (!validSSIT[index]) {
227 DPRINTF(StoreSet, "Inst %#x with index %i had no SSID\n",
228 PC, index);
229
230 // Return 0 if there's no valid entry.
231 return 0;
232 } else {
233 inst_SSID = SSIT[index];
234
235 assert(inst_SSID < LFSTSize);
236
237 if (!validLFST[inst_SSID]) {
238
239 DPRINTF(StoreSet, "Inst %#x with index %i and SSID %i had no "
240 "dependency\n", PC, index, inst_SSID);
241
242 return 0;
243 } else {
244 DPRINTF(StoreSet, "Inst %#x with index %i and SSID %i had LFST "
245 "inum of %i\n", PC, index, inst_SSID, LFST[inst_SSID]);
246
247 return LFST[inst_SSID];
248 }
249 }
250}
251
252void
253StoreSet::issued(Addr issued_PC, InstSeqNum issued_seq_num, bool is_store)
254{
255 // This only is updated upon a store being issued.
256 if (!is_store) {
257 return;
258 }
259
260 int index = calcIndex(issued_PC);
261
262 int store_SSID;
263
264 assert(index < SSITSize);
265
266 SeqNumMapIt store_list_it = storeList.find(issued_seq_num);
267
268 if (store_list_it != storeList.end()) {
269 storeList.erase(store_list_it);
270 }
271
272 // Make sure the SSIT still has a valid entry for the issued store.
273 if (!validSSIT[index]) {
274 return;
275 }
276
277 store_SSID = SSIT[index];
278
279 assert(store_SSID < LFSTSize);
280
281 // If the last fetched store in the store set refers to the store that
282 // was just issued, then invalidate the entry.
283 if (validLFST[store_SSID] && LFST[store_SSID] == issued_seq_num) {
284 DPRINTF(StoreSet, "StoreSet: store invalidated itself in LFST.\n");
285 validLFST[store_SSID] = false;
286 }
287}
288
289void
290StoreSet::squash(InstSeqNum squashed_num, unsigned tid)
291{
292 DPRINTF(StoreSet, "StoreSet: Squashing until inum %i\n",
293 squashed_num);
294
295 int idx;
296 SeqNumMapIt store_list_it = storeList.begin();
297
298 //@todo:Fix to only delete from correct thread
299 while (!storeList.empty()) {
300 idx = (*store_list_it).second;
301
302 if ((*store_list_it).first <= squashed_num) {
303 break;
304 }
305
306 bool younger = LFST[idx] > squashed_num;
307
308 if (validLFST[idx] && younger) {
309 DPRINTF(StoreSet, "Squashed [sn:%lli]\n", LFST[idx]);
310 validLFST[idx] = false;
311
312 storeList.erase(store_list_it++);
313 } else if (!validLFST[idx] && younger) {
314 storeList.erase(store_list_it++);
315 }
316 }
317}
318
319void
320StoreSet::clear()
321{
322 for (int i = 0; i < SSITSize; ++i) {
323 validSSIT[i] = false;
324 }
325
326 for (int i = 0; i < LFSTSize; ++i) {
327 validLFST[i] = false;
328 }
329
330 storeList.clear();
331}
332
333void
334StoreSet::dump()
335{
336 cprintf("storeList.size(): %i\n", storeList.size());
337 SeqNumMapIt store_list_it = storeList.begin();
338
339 int num = 0;
340
341 while (store_list_it != storeList.end()) {
342 cprintf("%i: [sn:%lli] SSID:%i\n",
343 num, (*store_list_it).first, (*store_list_it).second);
344 num++;
345 store_list_it++;
346 }
347}