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+/*
+ * Copyright (c) 2006 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: Gabe Black
+ */
+
+#ifndef __ARCH_ALPHA_PREDECODER_HH__
+#define __ARCH_ALPHA_PREDECODER_HH__
+
+#include "arch/alpha/types.hh"
+#include "base/misc.hh"
+#include "sim/host.hh"
+
+class ThreadContext;
+
+namespace AlphaISA
+{
+    class Predecoder
+    {
+      protected:
+        ThreadContext * tc;
+        //The pc of the current instruction
+        Addr fetchPC;
+        //The extended machine instruction being generated
+        ExtMachInst ext_inst;
+
+      public:
+        Predecoder(ThreadContext * _tc) : tc(_tc)
+        {}
+
+        ThreadContext * getTC()
+        {
+            return tc;
+        }
+
+        void setTC(ThreadContext * _tc)
+        {
+            tc = _tc;
+        }
+
+        void process()
+        {
+        }
+
+        //Use this to give data to the predecoder. This should be used
+        //when there is control flow.
+        void moreBytes(Addr pc, Addr off, MachInst inst)
+        {
+            fetchPC = pc;
+            assert(off == 0);
+            ext_inst = inst;
+#if FULL_SYSTEM
+            if (pc && 0x1)
+                ext_inst|=(static_cast<ExtMachInst>(pc & 0x1) << 32);
+#endif
+        }
+
+        //Use this to give data to the predecoder. This should be used
+        //when instructions are executed in order.
+        void moreBytes(MachInst machInst)
+        {
+            moreBytes(fetchPC + sizeof(machInst), 0, machInst);
+        }
+
+        bool needMoreBytes()
+        {
+            return true;
+        }
+
+        bool extMachInstReady()
+        {
+            return true;
+        }
+
+        //This returns a constant reference to the ExtMachInst to avoid a copy
+        const ExtMachInst & getExtMachInst()
+        {
+            return ext_inst;
+        }
+    };
+};
+
+#endif // __ARCH_ALPHA_PREDECODER_HH__