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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.
+ */
+
+#ifndef __CPU_BETA_CPU_BTB_HH__
+#define __CPU_BETA_CPU_BTB_HH__
+
+// For Addr type.
+#include "arch/alpha/isa_traits.hh"
+
+class DefaultBTB
+{
+ private:
+ struct BTBEntry
+ {
+ BTBEntry()
+ : tag(0), target(0), valid(false)
+ {
+ }
+
+ Addr tag;
+ Addr target;
+ bool valid;
+ };
+
+ public:
+ DefaultBTB(unsigned numEntries, unsigned tagBits,
+ unsigned instShiftAmt);
+
+ Addr lookup(const Addr &inst_PC);
+
+ bool valid(const Addr &inst_PC);
+
+ void update(const Addr &inst_PC, const Addr &target_PC);
+
+ private:
+ inline unsigned getIndex(const Addr &inst_PC);
+
+ inline Addr getTag(const Addr &inst_PC);
+
+ BTBEntry *btb;
+
+ unsigned numEntries;
+
+ unsigned idxMask;
+
+ unsigned tagBits;
+
+ unsigned tagMask;
+
+ unsigned instShiftAmt;
+
+ unsigned tagShiftAmt;
+};
+
+#endif // __CPU_BETA_CPU_BTB_HH__