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Diffstat (limited to 'src/mem/cache/tags/iic.cc')
| -rw-r--r-- | src/mem/cache/tags/iic.cc | 877 |
1 files changed, 877 insertions, 0 deletions
diff --git a/src/mem/cache/tags/iic.cc b/src/mem/cache/tags/iic.cc new file mode 100644 index 000000000..1377c8613 --- /dev/null +++ b/src/mem/cache/tags/iic.cc @@ -0,0 +1,877 @@ +/* + * Copyright (c) 2002-2005 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. + * + * Authors: Erik Hallnor + */ + +/** + * @file + * Definitions of the Indirect Index Cache tagstore. + */ + +#include <algorithm> +#include <string> +#include <vector> + +#include <math.h> + +#include "mem/cache/base_cache.hh" +#include "mem/cache/tags/iic.hh" +#include "base/intmath.hh" +#include "sim/root.hh" // for curTick + +#include "base/trace.hh" // for DPRINTF + + +using namespace std; + +/** Track the number of accesses to each cache set. */ +#define PROFILE_IIC 1 + +IIC::IIC(IIC::Params ¶ms) : + hashSets(params.numSets), blkSize(params.blkSize), assoc(params.assoc), + hitLatency(params.hitLatency), subSize(params.subblockSize), + numSub(blkSize/subSize), + trivialSize((floorLog2(params.size/subSize)*numSub)/8), + tagShift(floorLog2(blkSize)), blkMask(blkSize - 1), + subShift(floorLog2(subSize)), subMask(numSub - 1), + hashDelay(params.hashDelay), + numBlocks(params.size/subSize), + numTags(hashSets * assoc + params.size/blkSize -1), + numSecondary(params.size/blkSize), + tagNull(numTags), + primaryBound(hashSets * assoc) +{ + int i; + + // Check parameters + if (blkSize < 4 || !isPowerOf2(blkSize)) { + fatal("Block size must be at least 4 and a power of 2"); + } + if (hashSets <= 0 || !isPowerOf2(hashSets)) { + fatal("# of hashsets must be non-zero and a power of 2"); + } + if (assoc <= 0) { + fatal("associativity must be greater than zero"); + } + if (hitLatency <= 0) { + fatal("access latency must be greater than zero"); + } + if (numSub*subSize != blkSize) { + fatal("blocksize must be evenly divisible by subblock size"); + } + + // debug stuff + freeSecond = numSecondary; + + warmedUp = false; + warmupBound = params.size/blkSize; + + // Replacement Policy Initialization + repl = params.rp; + repl->setIIC(this); + + //last_miss_time = 0 + + // allocate data reference counters + dataReferenceCount = new int[numBlocks]; + memset(dataReferenceCount, 0, numBlocks*sizeof(int)); + + // Allocate storage for both internal data and block fast access data. + // We allocate it as one large chunk to reduce overhead and to make + // deletion easier. + int data_index = 0; + dataStore = new uint8_t[(numBlocks + numTags) * blkSize]; + dataBlks = new uint8_t*[numBlocks]; + for (i = 0; i < numBlocks; ++i) { + dataBlks[i] = &dataStore[data_index]; + freeDataBlock(i); + data_index += subSize; + } + + assert(data_index == numBlocks * subSize); + + // allocate and init tag store + tagStore = new IICTag[numTags]; + + int blkIndex = 0; + // allocate and init sets + sets = new IICSet[hashSets]; + for (i = 0; i < hashSets; ++i) { + sets[i].assoc = assoc; + sets[i].tags = new IICTag*[assoc]; + sets[i].chain_ptr = tagNull; + + for (int j = 0; j < assoc; ++j) { + IICTag *tag = &tagStore[blkIndex++]; + tag->chain_ptr = tagNull; + tag->data_ptr.resize(numSub); + tag->size = blkSize; + tag->trivialData = new uint8_t[trivialSize]; + tag->numData = 0; + sets[i].tags[j] = tag; + tag->set = i; + tag->data = &dataStore[data_index]; + data_index += blkSize; + } + } + + assert(blkIndex == primaryBound); + + for (i = primaryBound; i < tagNull; i++) { + tagStore[i].chain_ptr = i+1; + //setup data ptrs to subblocks + tagStore[i].data_ptr.resize(numSub); + tagStore[i].size = blkSize; + tagStore[i].trivialData = new uint8_t[trivialSize]; + tagStore[i].numData = 0; + tagStore[i].set = 0; + tagStore[i].data = &dataStore[data_index]; + data_index += blkSize; + } + freelist = primaryBound; +} + +IIC::~IIC() +{ + delete [] dataReferenceCount; + delete [] dataStore; + delete [] tagStore; + delete [] sets; +} + +/* register cache stats */ +void +IIC::regStats(const string &name) +{ + using namespace Stats; + + BaseTags::regStats(name); + + hitHashDepth.init(0, 20, 1); + missHashDepth.init(0, 20, 1); + setAccess.init(0, hashSets, 1); + + /** IIC Statistics */ + hitHashDepth + .name(name + ".hit_hash_depth_dist") + .desc("Dist. of Hash lookup depths") + .flags(pdf) + ; + + missHashDepth + .name(name + ".miss_hash_depth_dist") + .desc("Dist. of Hash lookup depths") + .flags(pdf) + ; + + repl->regStats(name); + + if (PROFILE_IIC) + setAccess + .name(name + ".set_access_dist") + .desc("Dist. of Accesses across sets") + .flags(pdf) + ; + + missDepthTotal + .name(name + ".miss_depth_total") + .desc("Total of miss depths") + ; + + hashMiss + .name(name + ".hash_miss") + .desc("Total of misses in hash table") + ; + + hitDepthTotal + .name(name + ".hit_depth_total") + .desc("Total of hit depths") + ; + + hashHit + .name(name + ".hash_hit") + .desc("Total of hites in hash table") + ; +} + +// probe cache for presence of given block. +bool +IIC::probe(Addr addr) const +{ + return (findBlock(addr) != NULL); +} + +IICTag* +IIC::findBlock(Addr addr, int &lat) +{ + Addr tag = extractTag(addr); + unsigned set = hash(addr); + int set_lat; + + unsigned long chain_ptr; + + if (PROFILE_IIC) + setAccess.sample(set); + + IICTag *tag_ptr = sets[set].findTag(tag, chain_ptr); + set_lat = 1; + if (tag_ptr == NULL && chain_ptr != tagNull) { + int secondary_depth; + tag_ptr = secondaryChain(tag, chain_ptr, &secondary_depth); + set_lat += secondary_depth; + // set depth for statistics fix this later!!! egh + sets[set].depth = set_lat; + + if (tag_ptr != NULL) { + /* need to move tag into primary table */ + // need to preserve chain: fix this egh + sets[set].tags[assoc-1]->chain_ptr = tag_ptr->chain_ptr; + tagSwap(tag_ptr - tagStore, sets[set].tags[assoc-1] - tagStore); + tag_ptr = sets[set].findTag(tag, chain_ptr); + assert(tag_ptr!=NULL); + } + + } + set_lat = set_lat * hashDelay + hitLatency; + if (tag_ptr != NULL) { + // IIC replacement: if this is not the first element of + // list, reorder + sets[set].moveToHead(tag_ptr); + + hitHashDepth.sample(sets[set].depth); + hashHit++; + hitDepthTotal += sets[set].depth; + tag_ptr->status |= BlkReferenced; + lat = set_lat; + if (tag_ptr->whenReady > curTick && tag_ptr->whenReady - curTick > set_lat) { + lat = tag_ptr->whenReady - curTick; + } + + tag_ptr->refCount += 1; + } + else { + // fall through: cache block not found, not a hit... + missHashDepth.sample(sets[set].depth); + hashMiss++; + missDepthTotal += sets[set].depth; + lat = set_lat; + } + return tag_ptr; +} + +IICTag* +IIC::findBlock(Packet * &pkt, int &lat) +{ + Addr addr = pkt->getAddr(); + + Addr tag = extractTag(addr); + unsigned set = hash(addr); + int set_lat; + + unsigned long chain_ptr; + + if (PROFILE_IIC) + setAccess.sample(set); + + IICTag *tag_ptr = sets[set].findTag(tag, chain_ptr); + set_lat = 1; + if (tag_ptr == NULL && chain_ptr != tagNull) { + int secondary_depth; + tag_ptr = secondaryChain(tag, chain_ptr, &secondary_depth); + set_lat += secondary_depth; + // set depth for statistics fix this later!!! egh + sets[set].depth = set_lat; + + if (tag_ptr != NULL) { + /* need to move tag into primary table */ + // need to preserve chain: fix this egh + sets[set].tags[assoc-1]->chain_ptr = tag_ptr->chain_ptr; + tagSwap(tag_ptr - tagStore, sets[set].tags[assoc-1] - tagStore); + tag_ptr = sets[set].findTag(tag, chain_ptr); + assert(tag_ptr!=NULL); + } + + } + set_lat = set_lat * hashDelay + hitLatency; + if (tag_ptr != NULL) { + // IIC replacement: if this is not the first element of + // list, reorder + sets[set].moveToHead(tag_ptr); + + hitHashDepth.sample(sets[set].depth); + hashHit++; + hitDepthTotal += sets[set].depth; + tag_ptr->status |= BlkReferenced; + lat = set_lat; + if (tag_ptr->whenReady > curTick && tag_ptr->whenReady - curTick > set_lat) { + lat = tag_ptr->whenReady - curTick; + } + + tag_ptr->refCount += 1; + } + else { + // fall through: cache block not found, not a hit... + missHashDepth.sample(sets[set].depth); + hashMiss++; + missDepthTotal += sets[set].depth; + lat = set_lat; + } + return tag_ptr; +} + +IICTag* +IIC::findBlock(Addr addr) const +{ + Addr tag = extractTag(addr); + unsigned set = hash(addr); + + unsigned long chain_ptr; + + IICTag *tag_ptr = sets[set].findTag(tag, chain_ptr); + if (tag_ptr == NULL && chain_ptr != tagNull) { + int secondary_depth; + tag_ptr = secondaryChain(tag, chain_ptr, &secondary_depth); + } + return tag_ptr; +} + + +IICTag* +IIC::findReplacement(Packet * &pkt, PacketList &writebacks, + BlkList &compress_blocks) +{ + DPRINTF(IIC, "Finding Replacement for %x\n", pkt->getAddr()); + unsigned set = hash(pkt->getAddr()); + IICTag *tag_ptr; + unsigned long *tmp_data = new unsigned long[numSub]; + + // Get a enough subblocks for a full cache line + for (int i = 0; i < numSub; ++i){ + tmp_data[i] = getFreeDataBlock(writebacks); + assert(dataReferenceCount[tmp_data[i]]==0); + } + + tag_ptr = getFreeTag(set, writebacks); + + tag_ptr->set = set; + for (int i=0; i< numSub; ++i) { + tag_ptr->data_ptr[i] = tmp_data[i]; + dataReferenceCount[tag_ptr->data_ptr[i]]++; + } + tag_ptr->numData = numSub; + assert(tag_ptr - tagStore < primaryBound); // make sure it is in primary + tag_ptr->chain_ptr = tagNull; + sets[set].moveToHead(tag_ptr); + delete [] tmp_data; + + list<unsigned long> tag_indexes; + repl->doAdvance(tag_indexes); + while (!tag_indexes.empty()) { + if (!tagStore[tag_indexes.front()].isCompressed()) { + compress_blocks.push_back(&tagStore[tag_indexes.front()]); + } + tag_indexes.pop_front(); + } + + tag_ptr->re = (void*)repl->add(tag_ptr-tagStore); + + return tag_ptr; +} + +void +IIC::freeReplacementBlock(PacketList & writebacks) +{ + IICTag *tag_ptr; + unsigned long data_ptr; + /* consult replacement policy */ + tag_ptr = &tagStore[repl->getRepl()]; + assert(tag_ptr->isValid()); + + DPRINTF(Cache, "Replacing %x in IIC: %s\n", + regenerateBlkAddr(tag_ptr->tag,0), + tag_ptr->isModified() ? "writeback" : "clean"); + /* write back replaced block data */ + if (tag_ptr && (tag_ptr->isValid())) { + replacements[0]++; + totalRefs += tag_ptr->refCount; + ++sampledRefs; + tag_ptr->refCount = 0; + + if (tag_ptr->isModified()) { +/* Packet * writeback = + buildWritebackReq(regenerateBlkAddr(tag_ptr->tag, 0), + tag_ptr->req->asid, tag_ptr->xc, blkSize, + tag_ptr->data, + tag_ptr->size); +*/ + Request *writebackReq = new Request(regenerateBlkAddr(tag_ptr->tag, 0), + blkSize, 0); + Packet *writeback = new Packet(writebackReq, Packet::Writeback, -1); + writeback->allocate(); + memcpy(writeback->getPtr<uint8_t>(), tag_ptr->data, blkSize); + + writebacks.push_back(writeback); + } + } + + // free the data blocks + for (int i = 0; i < tag_ptr->numData; ++i) { + data_ptr = tag_ptr->data_ptr[i]; + assert(dataReferenceCount[data_ptr]>0); + if (--dataReferenceCount[data_ptr] == 0) { + freeDataBlock(data_ptr); + } + } + freeTag(tag_ptr); +} + +unsigned long +IIC::getFreeDataBlock(PacketList & writebacks) +{ + struct IICTag *tag_ptr; + unsigned long data_ptr; + + tag_ptr = NULL; + /* find data block */ + while (blkFreelist.empty()) { + freeReplacementBlock(writebacks); + } + + data_ptr = blkFreelist.front(); + blkFreelist.pop_front(); + DPRINTF(IICMore,"Found free data at %d\n",data_ptr); + return data_ptr; +} + + + +IICTag* +IIC::getFreeTag(int set, PacketList & writebacks) +{ + unsigned long tag_index; + IICTag *tag_ptr; + // Add new tag + tag_ptr = sets[set].findFree(); + // if no free in primary, and secondary exists + if (!tag_ptr && numSecondary) { + // need to spill a tag into secondary storage + while (freelist == tagNull) { + // get replacements until one is in secondary + freeReplacementBlock(writebacks); + } + + tag_index = freelist; + freelist = tagStore[freelist].chain_ptr; + freeSecond--; + + assert(tag_index != tagNull); + tagSwap(tag_index, sets[set].tags[assoc-1] - tagStore); + tagStore[tag_index].chain_ptr = sets[set].chain_ptr; + sets[set].chain_ptr = tag_index; + + tag_ptr = sets[set].tags[assoc-1]; + } + DPRINTF(IICMore,"Found free tag at %d\n",tag_ptr - tagStore); + tagsInUse++; + if (!warmedUp && tagsInUse.value() >= warmupBound) { + warmedUp = true; + warmupCycle = curTick; + } + + return tag_ptr; +} + +void +IIC::freeTag(IICTag *tag_ptr) +{ + unsigned long tag_index, tmp_index; + // Fix tag_ptr + if (tag_ptr) { + // we have a tag to clear + DPRINTF(IICMore,"Freeing Tag for %x\n", + regenerateBlkAddr(tag_ptr->tag,0)); + tagsInUse--; + tag_ptr->status = 0; + tag_ptr->numData = 0; + tag_ptr->re = NULL; + tag_index = tag_ptr - tagStore; + if (tag_index >= primaryBound) { + // tag_ptr points to secondary store + assert(tag_index < tagNull); // remove this?? egh + if (tag_ptr->chain_ptr == tagNull) { + // need to fix chain list + unsigned tmp_set = hash(tag_ptr->tag << tagShift); + if (sets[tmp_set].chain_ptr == tag_index) { + sets[tmp_set].chain_ptr = tagNull; + } else { + tmp_index = sets[tmp_set].chain_ptr; + while (tmp_index != tagNull + && tagStore[tmp_index].chain_ptr != tag_index) { + tmp_index = tagStore[tmp_index].chain_ptr; + } + assert(tmp_index != tagNull); + tagStore[tmp_index].chain_ptr = tagNull; + } + tag_ptr->chain_ptr = freelist; + freelist = tag_index; + freeSecond++; + } else { + // copy next chained entry to this tag location + tmp_index = tag_ptr->chain_ptr; + tagSwap(tmp_index, tag_index); + tagStore[tmp_index].chain_ptr = freelist; + freelist = tmp_index; + freeSecond++; + } + } else { + // tag_ptr in primary hash table + assert(tag_index < primaryBound); + tag_ptr->status = 0; + unsigned tmp_set = hash(tag_ptr->tag << tagShift); + if (sets[tmp_set].chain_ptr != tagNull) { // collapse chain + tmp_index = sets[tmp_set].chain_ptr; + tagSwap(tag_index, tmp_index); + tagStore[tmp_index].chain_ptr = freelist; + freelist = tmp_index; + freeSecond++; + sets[tmp_set].chain_ptr = tag_ptr->chain_ptr; + sets[tmp_set].moveToTail(tag_ptr); + } + } + } +} + +void +IIC::freeDataBlock(unsigned long data_ptr) +{ + assert(dataReferenceCount[data_ptr] == 0); + DPRINTF(IICMore, "Freeing data at %d\n", data_ptr); + blkFreelist.push_front(data_ptr); +} + +/** Use a simple modulo hash. */ +#define SIMPLE_HASH 0 + +unsigned +IIC::hash(Addr addr) const { +#if SIMPLE_HASH + return extractTag(addr) % iic_hash_size; +#else + Addr tag, mask, x, y; + tag = extractTag(addr); + mask = hashSets-1; /* assumes iic_hash_size is a power of 2 */ + x = tag & mask; + y = (tag >> (int)(::log(hashSets)/::log(2))) & mask; + assert (x < hashSets && y < hashSets); + return x ^ y; +#endif +} + + +void +IICSet::moveToHead(IICTag *tag) +{ + if (tags[0] == tag) + return; + + // write 'next' block into blks[i], moving up from MRU toward LRU + // until we overwrite the block we moved to head. + + // start by setting up to write 'blk' into blks[0] + int i = 0; + IICTag *next = tag; + + do { + assert(i < assoc); + // swap blks[i] and next + IICTag *tmp = tags[i]; + tags[i] = next; + next = tmp; + ++i; + } while (next != tag); +} + +void +IICSet::moveToTail(IICTag *tag) +{ + if (tags[assoc-1] == tag) + return; + + // write 'next' block into blks[i], moving up from MRU toward LRU + // until we overwrite the block we moved to head. + + // start by setting up to write 'blk' into blks[0] + int i = assoc - 1; + IICTag *next = tag; + + do { + assert(i >= 0); + // swap blks[i] and next + IICTag *tmp = tags[i]; + tags[i] = next; + next = tmp; + --i; + } while (next != tag); +} + +void +IIC::tagSwap(unsigned long index1, unsigned long index2) +{ + DPRINTF(IIC,"Swapping tag[%d]=%x for tag[%d]=%x\n",index1, + tagStore[index1].tag<<tagShift, index2, + tagStore[index2].tag<<tagShift); + IICTag tmp_tag; + tmp_tag = tagStore[index1]; + tagStore[index1] = tagStore[index2]; + tagStore[index2] = tmp_tag; + if (tagStore[index1].isValid()) + repl->fixTag(tagStore[index1].re, index2, index1); + if (tagStore[index2].isValid()) + repl->fixTag(tagStore[index2].re, index1, index2); +} + + +IICTag * +IIC::secondaryChain(Addr tag, unsigned long chain_ptr, + int *_depth) const +{ + int depth = 0; + while (chain_ptr != tagNull) { + DPRINTF(IIC,"Searching secondary at %d for %x\n", chain_ptr, + tag<<tagShift); + if (tagStore[chain_ptr].tag == tag && + (tagStore[chain_ptr].isValid())) { + *_depth = depth; + return &tagStore[chain_ptr]; + } + depth++; + chain_ptr = tagStore[chain_ptr].chain_ptr; + } + *_depth = depth; + return NULL; +} + +void +IIC::decompressBlock(unsigned long index) +{ + IICTag *tag_ptr = &tagStore[index]; + if (tag_ptr->isCompressed()) { + // decompress the data here. + } +} + +void +IIC::compressBlock(unsigned long index) +{ + IICTag *tag_ptr = &tagStore[index]; + if (!tag_ptr->isCompressed()) { + // Compress the data here. + } +} + +void +IIC::invalidateBlk(Addr addr) +{ + IICTag* tag_ptr = findBlock(addr); + if (tag_ptr) { + for (int i = 0; i < tag_ptr->numData; ++i) { + dataReferenceCount[tag_ptr->data_ptr[i]]--; + if (dataReferenceCount[tag_ptr->data_ptr[i]] == 0) { + freeDataBlock(tag_ptr->data_ptr[i]); + } + } + repl->removeEntry(tag_ptr->re); + freeTag(tag_ptr); + } +} + +void +IIC::readData(IICTag *blk, uint8_t *data){ +// assert(cache->doData()); + assert(blk->size <= trivialSize || blk->numData > 0); + int data_size = blk->size; + if (data_size > trivialSize) { + for (int i = 0; i < blk->numData; ++i){ + memcpy(data+i*subSize, + &(dataBlks[blk->data_ptr[i]][0]), + (data_size>subSize)?subSize:data_size); + data_size -= subSize; + } + } else { + memcpy(data,blk->trivialData,data_size); + } +} + +void +IIC::writeData(IICTag *blk, uint8_t *write_data, int size, + PacketList & writebacks){ +// assert(cache->doData()); + assert(size < blkSize || !blk->isCompressed()); + DPRINTF(IIC, "Writing %d bytes to %x\n", size, + blk->tag<<tagShift); + // Find the number of subblocks needed, (round up) + int num_subs = (size + (subSize -1))/subSize; + if (size <= trivialSize) { + num_subs = 0; + } + assert(num_subs <= numSub); + if (num_subs > blk->numData) { + // need to allocate more data blocks + for (int i = blk->numData; i < num_subs; ++i){ + blk->data_ptr[i] = getFreeDataBlock(writebacks); + dataReferenceCount[blk->data_ptr[i]] += 1; + } + } else if (num_subs < blk->numData){ + // can free data blocks + for (int i=num_subs; i < blk->numData; ++i){ + // decrement reference count and compare to zero + /** + * @todo + * Make this work with copying. + */ + if (--dataReferenceCount[blk->data_ptr[i]] == 0) { + freeDataBlock(blk->data_ptr[i]); + } + } + } + + blk->numData = num_subs; + blk->size = size; + assert(size <= trivialSize || blk->numData > 0); + if (size > trivialSize){ + for (int i = 0; i < blk->numData; ++i){ + memcpy(&dataBlks[blk->data_ptr[i]][0], write_data + i*subSize, + (size>subSize)?subSize:size); + size -= subSize; + } + } else { + memcpy(blk->trivialData,write_data,size); + } +} + + +/** + * @todo This code can break if the src is evicted to get a tag for the dest. + */ +void +IIC::doCopy(Addr source, Addr dest, PacketList &writebacks) +{ +//Copy unsuported now +#if 0 + IICTag *dest_tag = findBlock(dest); + + if (dest_tag) { + for (int i = 0; i < dest_tag->numData; ++i) { + if (--dataReferenceCount[dest_tag->data_ptr[i]] == 0) { + freeDataBlock(dest_tag->data_ptr[i]); + } + } + // Reset replacement entry + } else { + dest_tag = getFreeTag(hash(dest), writebacks); + dest_tag->re = (void*) repl->add(dest_tag - tagStore); + dest_tag->set = hash(dest); + dest_tag->tag = extractTag(dest); + dest_tag->status = BlkValid | BlkWritable; + } + // Find the source tag here since it might move if we need to find a + // tag for the destination. + IICTag *src_tag = findBlock(source); + assert(src_tag); + assert(!cache->doData() || src_tag->size <= trivialSize + || src_tag->numData > 0); + // point dest to source data and inc counter + for (int i = 0; i < src_tag->numData; ++i) { + dest_tag->data_ptr[i] = src_tag->data_ptr[i]; + ++dataReferenceCount[dest_tag->data_ptr[i]]; + } + + // Maintain fast access data. + memcpy(dest_tag->data, src_tag->data, blkSize); + + dest_tag->xc = src_tag->xc; + dest_tag->size = src_tag->size; + dest_tag->numData = src_tag->numData; + if (src_tag->numData == 0) { + // Data is stored in the trivial data, just copy it. + memcpy(dest_tag->trivialData, src_tag->trivialData, src_tag->size); + } + + dest_tag->status |= BlkDirty; + if (dest_tag->size < blkSize) { + dest_tag->status |= BlkCompressed; + } else { + dest_tag->status &= ~BlkCompressed; + } +#endif +} + +void +IIC::fixCopy(Packet * &pkt, PacketList &writebacks) +{ +#if 0 + // if reference counter is greater than 1, do copy + // else do write + Addr blk_addr = blkAlign(pkt->getAddr); + IICTag* blk = findBlock(blk_addr); + + if (blk->numData > 0 && dataReferenceCount[blk->data_ptr[0]] != 1) { + // copy the data + // Mark the block as referenced so it doesn't get replaced. + blk->status |= BlkReferenced; + for (int i = 0; i < blk->numData; ++i){ + unsigned long new_data = getFreeDataBlock(writebacks); + // Need to refresh pointer + /** + * @todo Remove this refetch once we change IIC to pointer based + */ + blk = findBlock(blk_addr); + assert(blk); + if (cache->doData()) { + memcpy(&(dataBlks[new_data][0]), + &(dataBlks[blk->data_ptr[i]][0]), + subSize); + } + dataReferenceCount[blk->data_ptr[i]]--; + dataReferenceCount[new_data]++; + blk->data_ptr[i] = new_data; + } + } +#endif +} + +void +IIC::cleanupRefs() +{ + for (int i = 0; i < numTags; ++i) { + if (tagStore[i].isValid()) { + totalRefs += tagStore[i].refCount; + ++sampledRefs; + } + } +} |