2 files changed, 25 insertions, 9 deletions

diff --git a/src/arch/x86/decoder.cc b/src/arch/x86/decoder.cc
index d7199fa82..5fb2dcaf4 100644
--- a/src/arch/x86/decoder.cc
+++ b/src/arch/x86/decoder.cc
@@ -408,6 +408,25 @@ Decoder::State Decoder::doImmediateState()
     return nextState;
 }
 
-DecodeCache Decoder::defaultCache;
+DecodeCache::InstMap Decoder::instMap;
+DecodeCache::AddrMap<StaticInstPtr> Decoder::decodePages;
+
+StaticInstPtr
+Decoder::decode(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 = decodeInst(mach_inst);
+    instMap[mach_inst] = si;
+    return si;
+}
 
 }
diff --git a/src/arch/x86/decoder.hh b/src/arch/x86/decoder.hh
index 300e2238c..725d443d6 100644
--- a/src/arch/x86/decoder.hh
+++ b/src/arch/x86/decoder.hh
@@ -40,7 +40,7 @@
 #include "base/trace.hh"
 #include "base/types.hh"
 #include "cpu/decode_cache.hh"
-#include "cpu/static_inst_fwd.hh"
+#include "cpu/static_inst.hh"
 #include "debug/Decoder.hh"
 
 class ThreadContext;
@@ -218,8 +218,9 @@ class Decoder
     }
 
   protected:
-    /// A cache of decoded instruction objects.
-    static DecodeCache defaultCache;
+    /// Caching for decoded instruction objects.
+    static DecodeCache::InstMap instMap;
+    static DecodeCache::AddrMap<StaticInstPtr> decodePages;
 
   public:
     StaticInstPtr decodeInst(ExtMachInst mach_inst);
@@ -227,11 +228,7 @@ class Decoder
     /// Decode a machine instruction.
     /// @param mach_inst The binary instruction to decode.
     /// @retval A pointer to the corresponding StaticInst object.
-    StaticInstPtr
-    decode(ExtMachInst mach_inst, Addr addr)
-    {
-        return defaultCache.decode(this, mach_inst, addr);
-    }
+    StaticInstPtr decode(ExtMachInst mach_inst, Addr addr);
 
     StaticInstPtr
     decode(X86ISA::PCState &nextPC)