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-rw-r--r--src/cpu/o3/store_set.cc282
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diff --git a/src/cpu/o3/store_set.cc b/src/cpu/o3/store_set.cc
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+/*
+ * Copyright (c) 2004-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "base/trace.hh"
+#include "cpu/o3/store_set.hh"
+
+StoreSet::StoreSet(int _SSIT_size, int _LFST_size)
+ : SSIT_size(_SSIT_size), LFST_size(_LFST_size)
+{
+ DPRINTF(StoreSet, "StoreSet: Creating store set object.\n");
+ DPRINTF(StoreSet, "StoreSet: SSIT size: %i, LFST size: %i.\n",
+ SSIT_size, LFST_size);
+
+ SSIT = new SSID[SSIT_size];
+
+ validSSIT.resize(SSIT_size);
+
+ for (int i = 0; i < SSIT_size; ++i)
+ validSSIT[i] = false;
+
+ LFST = new InstSeqNum[LFST_size];
+
+ validLFST.resize(LFST_size);
+
+ SSCounters = new int[LFST_size];
+
+ for (int i = 0; i < LFST_size; ++i)
+ {
+ validLFST[i] = false;
+ SSCounters[i] = 0;
+ }
+
+ index_mask = SSIT_size - 1;
+
+ offset_bits = 2;
+}
+
+void
+StoreSet::violation(Addr store_PC, Addr load_PC)
+{
+ int load_index = calcIndex(load_PC);
+ int store_index = calcIndex(store_PC);
+
+ assert(load_index < SSIT_size && store_index < SSIT_size);
+
+ bool valid_load_SSID = validSSIT[load_index];
+ bool valid_store_SSID = validSSIT[store_index];
+
+ if (!valid_load_SSID && !valid_store_SSID) {
+ // Calculate a new SSID here.
+ SSID new_set = calcSSID(load_PC);
+
+ validSSIT[load_index] = true;
+
+ SSIT[load_index] = new_set;
+
+ validSSIT[store_index] = true;
+
+ SSIT[store_index] = new_set;
+
+ assert(new_set < LFST_size);
+
+ SSCounters[new_set]++;
+
+
+ DPRINTF(StoreSet, "StoreSet: Neither load nor store had a valid "
+ "storeset, creating a new one: %i for load %#x, store %#x\n",
+ new_set, load_PC, store_PC);
+ } else if (valid_load_SSID && !valid_store_SSID) {
+ SSID load_SSID = SSIT[load_index];
+
+ validSSIT[store_index] = true;
+
+ SSIT[store_index] = load_SSID;
+
+ assert(load_SSID < LFST_size);
+
+ SSCounters[load_SSID]++;
+
+ DPRINTF(StoreSet, "StoreSet: Load had a valid store set. Adding "
+ "store to that set: %i for load %#x, store %#x\n",
+ load_SSID, load_PC, store_PC);
+ } else if (!valid_load_SSID && valid_store_SSID) {
+ SSID store_SSID = SSIT[store_index];
+
+ validSSIT[load_index] = true;
+
+ SSIT[load_index] = store_SSID;
+
+ // Because we are having a load point to an already existing set,
+ // the size of the store set is not incremented.
+
+ DPRINTF(StoreSet, "StoreSet: Store had a valid store set: %i for "
+ "load %#x, store %#x\n",
+ store_SSID, load_PC, store_PC);
+ } else {
+ SSID load_SSID = SSIT[load_index];
+ SSID store_SSID = SSIT[store_index];
+
+ assert(load_SSID < LFST_size && store_SSID < LFST_size);
+
+ int load_SS_size = SSCounters[load_SSID];
+ int store_SS_size = SSCounters[store_SSID];
+
+ // If the load has the bigger store set, then assign the store
+ // to the same store set as the load. Otherwise vice-versa.
+ if (load_SS_size > store_SS_size) {
+ SSIT[store_index] = load_SSID;
+
+ SSCounters[load_SSID]++;
+ SSCounters[store_SSID]--;
+
+ DPRINTF(StoreSet, "StoreSet: Load had bigger store set: %i; "
+ "for load %#x, store %#x\n",
+ load_SSID, load_PC, store_PC);
+ } else {
+ SSIT[load_index] = store_SSID;
+
+ SSCounters[store_SSID]++;
+ SSCounters[load_SSID]--;
+
+ DPRINTF(StoreSet, "StoreSet: Store had bigger store set: %i; "
+ "for load %#x, store %#x\n",
+ store_SSID, load_PC, store_PC);
+ }
+ }
+}
+
+void
+StoreSet::insertLoad(Addr load_PC, InstSeqNum load_seq_num)
+{
+ // Does nothing.
+ return;
+}
+
+void
+StoreSet::insertStore(Addr store_PC, InstSeqNum store_seq_num)
+{
+ int index = calcIndex(store_PC);
+
+ int store_SSID;
+
+ assert(index < SSIT_size);
+
+ if (!validSSIT[index]) {
+ // Do nothing if there's no valid entry.
+ return;
+ } else {
+ store_SSID = SSIT[index];
+
+ assert(store_SSID < LFST_size);
+
+ // Update the last store that was fetched with the current one.
+ LFST[store_SSID] = store_seq_num;
+
+ validLFST[store_SSID] = 1;
+
+ DPRINTF(StoreSet, "Store %#x updated the LFST, SSID: %i\n",
+ store_PC, store_SSID);
+ }
+}
+
+InstSeqNum
+StoreSet::checkInst(Addr PC)
+{
+ int index = calcIndex(PC);
+
+ int inst_SSID;
+
+ assert(index < SSIT_size);
+
+ if (!validSSIT[index]) {
+ DPRINTF(StoreSet, "Inst %#x with index %i had no SSID\n",
+ PC, index);
+
+ // Return 0 if there's no valid entry.
+ return 0;
+ } else {
+ inst_SSID = SSIT[index];
+
+ assert(inst_SSID < LFST_size);
+
+ if (!validLFST[inst_SSID]) {
+
+ DPRINTF(StoreSet, "Inst %#x with index %i and SSID %i had no "
+ "dependency\n", PC, index, inst_SSID);
+
+ return 0;
+ } else {
+ DPRINTF(StoreSet, "Inst %#x with index %i and SSID %i had LFST "
+ "inum of %i\n", PC, index, inst_SSID, LFST[inst_SSID]);
+
+ return LFST[inst_SSID];
+ }
+ }
+}
+
+void
+StoreSet::issued(Addr issued_PC, InstSeqNum issued_seq_num, bool is_store)
+{
+ // This only is updated upon a store being issued.
+ if (!is_store) {
+ return;
+ }
+
+ int index = calcIndex(issued_PC);
+
+ int store_SSID;
+
+ assert(index < SSIT_size);
+
+ // Make sure the SSIT still has a valid entry for the issued store.
+ if (!validSSIT[index]) {
+ return;
+ }
+
+ store_SSID = SSIT[index];
+
+ assert(store_SSID < LFST_size);
+
+ // If the last fetched store in the store set refers to the store that
+ // was just issued, then invalidate the entry.
+ if (validLFST[store_SSID] && LFST[store_SSID] == issued_seq_num) {
+ DPRINTF(StoreSet, "StoreSet: store invalidated itself in LFST.\n");
+ validLFST[store_SSID] = false;
+ }
+}
+
+void
+StoreSet::squash(InstSeqNum squashed_num)
+{
+ // Not really sure how to do this well.
+ // Generally this is small enough that it should be okay; short circuit
+ // evaluation should take care of invalid entries.
+
+ DPRINTF(StoreSet, "StoreSet: Squashing until inum %i\n",
+ squashed_num);
+
+ for (int i = 0; i < LFST_size; ++i) {
+ if (validLFST[i] && LFST[i] < squashed_num) {
+ validLFST[i] = false;
+ }
+ }
+}
+
+void
+StoreSet::clear()
+{
+ for (int i = 0; i < SSIT_size; ++i) {
+ validSSIT[i] = false;
+ }
+
+ for (int i = 0; i < LFST_size; ++i) {
+ validLFST[i] = false;
+ }
+}
+
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