ISA,CPU: Generalize and split out the components of the decode cache.

This will allow it to be specialized by the ISAs. The existing caching scheme
is provided by the BasicDecodeCache in the GenericISA namespace and is built
from the generalized components.

--HG--
rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc

3 files changed, 153 insertions, 0 deletions

diff --git a/src/arch/generic/SConscript b/src/arch/generic/SConscript
new file mode 100644
index 000000000..f2edc805d
--- /dev/null
+++ b/src/arch/generic/SConscript
@@ -0,0 +1,31 @@
+# Copyright (c) 2012 Google
+# 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
+
+Import('*')
+
+Source('decode_cache.cc')
diff --git a/src/arch/generic/decode_cache.cc b/src/arch/generic/decode_cache.cc
new file mode 100644
index 000000000..7211ba355
--- /dev/null
+++ b/src/arch/generic/decode_cache.cc
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2011-2012 Google
+ * 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
+ */
+
+#include "arch/generic/decode_cache.hh"
+#include "arch/decoder.hh"
+#include "arch/types.hh"
+#include "config/the_isa.hh"
+#include "cpu/static_inst.hh"
+
+namespace GenericISA
+{
+
+StaticInstPtr
+BasicDecodeCache::decode(TheISA::Decoder *decoder,
+        TheISA::ExtMachInst mach_inst, Addr addr)
+{
+    StaticInstPtr &si = decodePages.lookup(addr);
+    if (si && (si->machInst == mach_inst))
+        return si;
+
+    DecodeCache::InstMap::iterator iter = instMap.find(mach_inst);
+    if (iter != instMap.end()) {
+        si = iter->second;
+        return si;
+    }
+
+    si = decoder->decodeInst(mach_inst);
+    instMap[mach_inst] = si;
+    return si;
+}
+
+} // namespace GenericISA
diff --git a/src/arch/generic/decode_cache.hh b/src/arch/generic/decode_cache.hh
new file mode 100644
index 000000000..c6bce7226
--- /dev/null
+++ b/src/arch/generic/decode_cache.hh
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2011 Google
+ * 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_GENERIC_DECODE_CACHE_HH__
+#define __ARCH_GENERIC_DECODE_CACHE_HH__
+
+#include "arch/types.hh"
+#include "config/the_isa.hh"
+#include "cpu/decode_cache.hh"
+#include "cpu/static_inst_fwd.hh"
+
+namespace TheISA
+{
+    class Decoder;
+}
+
+namespace GenericISA
+{
+
+class BasicDecodeCache
+{
+  private:
+    DecodeCache::InstMap instMap;
+    DecodeCache::AddrMap<StaticInstPtr> decodePages;
+
+  public:
+    /// Decode a machine instruction.
+    /// @param mach_inst The binary instruction to decode.
+    /// @retval A pointer to the corresponding StaticInst object.
+    StaticInstPtr decode(TheISA::Decoder * const decoder,
+            TheISA::ExtMachInst mach_inst, Addr addr);
+};
+
+} // namespace GenericISA
+
+#endif // __ARCH_GENERIC_DECODE_CACHE_HH__