cache: pull CacheSet out of LRU so that other tags can use associative sets.

1 files changed, 68 insertions, 0 deletions

diff --git a/src/mem/cache/tags/cacheset.cc b/src/mem/cache/tags/cacheset.cc
new file mode 100644
index 000000000..dea1a6b45
--- /dev/null
+++ b/src/mem/cache/tags/cacheset.cc
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2009 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: Lisa Hsu
+ */
+
+
+#include "mem/cache/tags/cacheset.hh"
+
+CacheBlk*
+CacheSet::findBlk(Addr tag) const
+{
+    for (int i = 0; i < assoc; ++i) {
+        if (blks[i]->tag == tag && blks[i]->isValid()) {
+            return blks[i];
+        }
+    }
+    return 0;
+}
+
+void
+CacheSet::moveToHead(CacheBlk *blk)
+{
+    // nothing to do if blk is already head
+    if (blks[0] == blk)
+        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;
+    CacheBlk *next = blk;
+
+    do {
+        assert(i < assoc);
+        // swap blks[i] and next
+        CacheBlk *tmp = blks[i];
+        blks[i] = next;
+        next = tmp;
+        ++i;
+    } while (next != blk);
+}
+