Add support for microcode and pull out the special branch delay slot handling. Branch delay slots need to be squash on a mispredict as well because the nnpc they saw was incorrect.

--HG--
extra : convert_revision : 8b9c603616bcad254417a7a3fa3edfb4c8728719

14 files changed, 291 insertions, 85 deletions

diff --git a/src/cpu/base_dyn_inst.hh b/src/cpu/base_dyn_inst.hh
index b02038b3e..1311e5cf2 100644
--- a/src/cpu/base_dyn_inst.hh
+++ b/src/cpu/base_dyn_inst.hh
@@ -209,6 +209,9 @@ class BaseDynInst : public FastAlloc, public RefCounted
     /** PC of this instruction. */
     Addr PC;
 
+    /** Micro PC of this instruction. */
+    Addr microPC;
+
   protected:
     /** Next non-speculative PC.  It is not filled in at fetch, but rather
      *  once the target of the branch is truly known (either decode or
@@ -219,12 +222,18 @@ class BaseDynInst : public FastAlloc, public RefCounted
     /** Next non-speculative NPC. Target PC for Mips or Sparc. */
     Addr nextNPC;
 
+    /** Next non-speculative micro PC. */
+    Addr nextMicroPC;
+
     /** Predicted next PC. */
     Addr predPC;
 
     /** Predicted next NPC. */
     Addr predNPC;
 
+    /** Predicted next microPC */
+    Addr predMicroPC;
+
     /** If this is a branch that was predicted taken */
     bool predTaken;
 
@@ -340,6 +349,17 @@ class BaseDynInst : public FastAlloc, public RefCounted
     {
         _flatDestRegIdx[idx] = flattened_dest;
     }
+    /** BaseDynInst constructor given a binary instruction.
+     *  @param staticInst A StaticInstPtr to the underlying instruction.
+     *  @param PC The PC of the instruction.
+     *  @param pred_PC The predicted next PC.
+     *  @param pred_NPC The predicted next NPC.
+     *  @param seq_num The sequence number of the instruction.
+     *  @param cpu Pointer to the instruction's CPU.
+     */
+    BaseDynInst(StaticInstPtr staticInst, Addr PC, Addr NPC, Addr microPC,
+            Addr pred_PC, Addr pred_NPC, Addr pred_MicroPC,
+            InstSeqNum seq_num, ImplCPU *cpu);
 
     /** BaseDynInst constructor given a binary instruction.
      *  @param inst The binary instruction.
@@ -349,8 +369,8 @@ class BaseDynInst : public FastAlloc, public RefCounted
      *  @param seq_num The sequence number of the instruction.
      *  @param cpu Pointer to the instruction's CPU.
      */
-    BaseDynInst(TheISA::ExtMachInst inst, Addr PC, Addr NPC,
-            Addr pred_PC, Addr pred_NPC,
+    BaseDynInst(TheISA::ExtMachInst inst, Addr PC, Addr NPC, Addr microPC,
+            Addr pred_PC, Addr pred_NPC, Addr pred_MicroPC,
             InstSeqNum seq_num, ImplCPU *cpu);
 
     /** BaseDynInst constructor given a StaticInst pointer.
@@ -402,11 +422,18 @@ class BaseDynInst : public FastAlloc, public RefCounted
 #endif
     }
 
+    Addr readNextMicroPC()
+    {
+        return nextMicroPC;
+    }
+
     /** Set the predicted target of this current instruction. */
-    void setPredTarg(Addr predicted_PC, Addr predicted_NPC)
+    void setPredTarg(Addr predicted_PC, Addr predicted_NPC,
+            Addr predicted_MicroPC)
     {
         predPC = predicted_PC;
         predNPC = predicted_NPC;
+        predMicroPC = predicted_MicroPC;
     }
 
     /** Returns the predicted PC immediately after the branch. */
@@ -415,6 +442,9 @@ class BaseDynInst : public FastAlloc, public RefCounted
     /** Returns the predicted PC two instructions after the branch */
     Addr readPredNPC() { return predNPC; }
 
+    /** Returns the predicted micro PC after the branch */
+    Addr readPredMicroPC() { return predMicroPC; }
+
     /** Returns whether the instruction was predicted taken or not. */
     bool readPredTaken()
     {
@@ -430,7 +460,8 @@ class BaseDynInst : public FastAlloc, public RefCounted
     bool mispredicted()
     {
         return readPredPC() != readNextPC() ||
-            readPredNPC() != readNextNPC();
+            readPredNPC() != readNextNPC() ||
+            readPredMicroPC() != readNextMicroPC();
     }
 
     //
@@ -467,6 +498,12 @@ class BaseDynInst : public FastAlloc, public RefCounted
     bool isQuiesce() const { return staticInst->isQuiesce(); }
     bool isIprAccess() const { return staticInst->isIprAccess(); }
     bool isUnverifiable() const { return staticInst->isUnverifiable(); }
+    bool isMacroOp() const { return staticInst->isMacroOp(); }
+    bool isMicroOp() const { return staticInst->isMicroOp(); }
+    bool isDelayedCommit() const { return staticInst->isDelayedCommit(); }
+    bool isLastMicroOp() const { return staticInst->isLastMicroOp(); }
+    bool isFirstMicroOp() const { return staticInst->isFirstMicroOp(); }
+    bool isMicroBranch() const { return staticInst->isMicroBranch(); }
 
     /** Temporarily sets this instruction as a serialize before instruction. */
     void setSerializeBefore() { status.set(SerializeBefore); }
@@ -700,20 +737,28 @@ class BaseDynInst : public FastAlloc, public RefCounted
     /** Read the PC of this instruction. */
     const Addr readPC() const { return PC; }
 
+    /**Read the micro PC of this instruction. */
+    const Addr readMicroPC() const { return microPC; }
+
     /** Set the next PC of this instruction (its actual target). */
-    void setNextPC(uint64_t val)
+    void setNextPC(Addr val)
     {
         nextPC = val;
     }
 
     /** Set the next NPC of this instruction (the target in Mips or Sparc).*/
-    void setNextNPC(uint64_t val)
+    void setNextNPC(Addr val)
     {
 #if ISA_HAS_DELAY_SLOT
         nextNPC = val;
 #endif
     }
 
+    void setNextMicroPC(Addr val)
+    {
+        nextMicroPC = val;
+    }
+
     /** Sets the ASID. */
     void setASID(short addr_space_id) { asid = addr_space_id; }
 
diff --git a/src/cpu/base_dyn_inst_impl.hh b/src/cpu/base_dyn_inst_impl.hh
index a1c866336..acf8af9cf 100644
--- a/src/cpu/base_dyn_inst_impl.hh
+++ b/src/cpu/base_dyn_inst_impl.hh
@@ -62,19 +62,66 @@ my_hash_t thishash;
 #endif
 
 template <class Impl>
-BaseDynInst<Impl>::BaseDynInst(TheISA::ExtMachInst machInst,
+BaseDynInst<Impl>::BaseDynInst(StaticInstPtr _staticInst,
                                Addr inst_PC, Addr inst_NPC,
+                               Addr inst_MicroPC,
                                Addr pred_PC, Addr pred_NPC,
+                               Addr pred_MicroPC,
                                InstSeqNum seq_num, ImplCPU *cpu)
-  : staticInst(machInst), traceData(NULL), cpu(cpu)
+  : staticInst(_staticInst), traceData(NULL), cpu(cpu)
 {
     seqNum = seq_num;
 
+    bool nextIsMicro =
+        staticInst->isMicroOp() && !staticInst->isLastMicroOp();
+
     PC = inst_PC;
-    nextPC = inst_NPC;
-    nextNPC = nextPC + sizeof(TheISA::MachInst);
+    microPC = inst_MicroPC;
+    if (nextIsMicro) {
+        nextPC = inst_PC;
+        nextNPC = inst_NPC;
+        nextMicroPC = microPC + 1;
+    } else {
+        nextPC = inst_NPC;
+        nextNPC = nextPC + sizeof(TheISA::MachInst);
+        nextMicroPC = 0;
+    }
+    predPC = pred_PC;
+    predNPC = pred_NPC;
+    predMicroPC = pred_MicroPC;
+    predTaken = false;
+
+    initVars();
+}
+
+template <class Impl>
+BaseDynInst<Impl>::BaseDynInst(TheISA::ExtMachInst inst,
+                               Addr inst_PC, Addr inst_NPC,
+                               Addr inst_MicroPC,
+                               Addr pred_PC, Addr pred_NPC,
+                               Addr pred_MicroPC,
+                               InstSeqNum seq_num, ImplCPU *cpu)
+  : staticInst(inst), traceData(NULL), cpu(cpu)
+{
+    seqNum = seq_num;
+
+    bool nextIsMicro =
+        staticInst->isMicroOp() && !staticInst->isLastMicroOp();
+
+    PC = inst_PC;
+    microPC = inst_MicroPC;
+    if (nextIsMicro) {
+        nextPC = inst_PC;
+        nextNPC = inst_NPC;
+        nextMicroPC = microPC + 1;
+    } else {
+        nextPC = inst_NPC;
+        nextNPC = nextPC + sizeof(TheISA::MachInst);
+        nextMicroPC = 0;
+    }
     predPC = pred_PC;
     predNPC = pred_NPC;
+    predMicroPC = pred_MicroPC;
     predTaken = false;
 
     initVars();
diff --git a/src/cpu/o3/comm.hh b/src/cpu/o3/comm.hh
index 8d7bb95f4..fb772060b 100644
--- a/src/cpu/o3/comm.hh
+++ b/src/cpu/o3/comm.hh
@@ -87,9 +87,10 @@ struct DefaultIEWDefaultCommit {
     bool squash[Impl::MaxThreads];
     bool branchMispredict[Impl::MaxThreads];
     bool branchTaken[Impl::MaxThreads];
-    uint64_t mispredPC[Impl::MaxThreads];
-    uint64_t nextPC[Impl::MaxThreads];
-    uint64_t nextNPC[Impl::MaxThreads];
+    Addr mispredPC[Impl::MaxThreads];
+    Addr nextPC[Impl::MaxThreads];
+    Addr nextNPC[Impl::MaxThreads];
+    Addr nextMicroPC[Impl::MaxThreads];
     InstSeqNum squashedSeqNum[Impl::MaxThreads];
 
     bool includeSquashInst[Impl::MaxThreads];
@@ -118,9 +119,10 @@ struct TimeBufStruct {
         // struct as it is used pretty frequently.
         bool branchMispredict;
         bool branchTaken;
-        uint64_t mispredPC;
-        uint64_t nextPC;
-        uint64_t nextNPC;
+        Addr mispredPC;
+        Addr nextPC;
+        Addr nextNPC;
+        Addr nextMicroPC;
 
         unsigned branchCount;
     };
@@ -158,9 +160,10 @@ struct TimeBufStruct {
 
         bool branchMispredict;
         bool branchTaken;
-        uint64_t mispredPC;
-        uint64_t nextPC;
-        uint64_t nextNPC;
+        Addr mispredPC;
+        Addr nextPC;
+        Addr nextNPC;
+        Addr nextMicroPC;
 
         // Represents the instruction that has either been retired or
         // squashed.  Similar to having a single bus that broadcasts the
diff --git a/src/cpu/o3/commit.hh b/src/cpu/o3/commit.hh
index fba618c14..27bdd20c5 100644
--- a/src/cpu/o3/commit.hh
+++ b/src/cpu/o3/commit.hh
@@ -279,25 +279,37 @@ class DefaultCommit
     /** Returns the PC of the head instruction of the ROB.
      * @todo: Probably remove this function as it returns only thread 0.
      */
-    uint64_t readPC() { return PC[0]; }
+    Addr readPC() { return PC[0]; }
 
     /** Returns the PC of a specific thread. */
-    uint64_t readPC(unsigned tid) { return PC[tid]; }
+    Addr readPC(unsigned tid) { return PC[tid]; }
 
     /** Sets the PC of a specific thread. */
-    void setPC(uint64_t val, unsigned tid) { PC[tid] = val; }
+    void setPC(Addr val, unsigned tid) { PC[tid] = val; }
+
+    /** Reads the micro PC of a specific thread. */
+    Addr readMicroPC(unsigned tid) { return microPC[tid]; }
+
+    /** Sets the micro PC of a specific thread */
+    void setMicroPC(Addr val, unsigned tid) { microPC[tid] = val; }
 
     /** Reads the next PC of a specific thread. */
-    uint64_t readNextPC(unsigned tid) { return nextPC[tid]; }
+    Addr readNextPC(unsigned tid) { return nextPC[tid]; }
 
     /** Sets the next PC of a specific thread. */
-    void setNextPC(uint64_t val, unsigned tid) { nextPC[tid] = val; }
+    void setNextPC(Addr val, unsigned tid) { nextPC[tid] = val; }
 
     /** Reads the next NPC of a specific thread. */
-    uint64_t readNextNPC(unsigned tid) { return nextNPC[tid]; }
+    Addr readNextNPC(unsigned tid) { return nextNPC[tid]; }
 
     /** Sets the next NPC of a specific thread. */
-    void setNextNPC(uint64_t val, unsigned tid) { nextNPC[tid] = val; }
+    void setNextNPC(Addr val, unsigned tid) { nextNPC[tid] = val; }
+
+    /** Reads the micro PC of a specific thread. */
+    Addr readNextMicroPC(unsigned tid) { return nextMicroPC[tid]; }
+
+    /** Sets the micro PC of a specific thread */
+    void setNextMicroPC(Addr val, unsigned tid) { nextMicroPC[tid] = val; }
 
   private:
     /** Time buffer interface. */
@@ -402,12 +414,20 @@ class DefaultCommit
      */
     Addr PC[Impl::MaxThreads];
 
+    /** The commit micro PC of each thread.  Refers to the instruction that
+     * is currently being processed/committed.
+     */
+    Addr microPC[Impl::MaxThreads];
+
     /** The next PC of each thread. */
     Addr nextPC[Impl::MaxThreads];
 
     /** The next NPC of each thread. */
     Addr nextNPC[Impl::MaxThreads];
 
+    /** The next micro PC of each thread. */
+    Addr nextMicroPC[Impl::MaxThreads];
+
     /** The sequence number of the youngest valid instruction in the ROB. */
     InstSeqNum youngestSeqNum[Impl::MaxThreads];
 
diff --git a/src/cpu/o3/commit_impl.hh b/src/cpu/o3/commit_impl.hh
index 9dd5ed291..fc24d7edc 100644
--- a/src/cpu/o3/commit_impl.hh
+++ b/src/cpu/o3/commit_impl.hh
@@ -124,7 +124,7 @@ DefaultCommit<Impl>::DefaultCommit(O3CPU *_cpu, Params *params)
         committedStores[i] = false;
         trapSquash[i] = false;
         tcSquash[i] = false;
-        PC[i] = nextPC[i] = nextNPC[i] = 0;
+        microPC[i] = nextMicroPC[i] = PC[i] = nextPC[i] = nextNPC[i] = 0;
     }
 #if FULL_SYSTEM
     interrupt = NoFault;
@@ -508,6 +508,7 @@ DefaultCommit<Impl>::squashAll(unsigned tid)
 
     toIEW->commitInfo[tid].nextPC = PC[tid];
     toIEW->commitInfo[tid].nextNPC = nextPC[tid];
+    toIEW->commitInfo[tid].nextMicroPC = nextMicroPC[tid];
 }
 
 template <class Impl>
@@ -768,6 +769,7 @@ DefaultCommit<Impl>::commit()
 
             toIEW->commitInfo[tid].nextPC = fromIEW->nextPC[tid];
             toIEW->commitInfo[tid].nextNPC = fromIEW->nextNPC[tid];
+            toIEW->commitInfo[tid].nextMicroPC = fromIEW->nextMicroPC[tid];
 
             toIEW->commitInfo[tid].mispredPC = fromIEW->mispredPC[tid];
 
@@ -877,6 +879,7 @@ DefaultCommit<Impl>::commitInsts()
             PC[tid] = head_inst->readPC();
             nextPC[tid] = head_inst->readNextPC();
             nextNPC[tid] = head_inst->readNextNPC();
+            nextMicroPC[tid] = head_inst->readNextMicroPC();
 
             // Increment the total number of non-speculative instructions
             // executed.
@@ -905,12 +908,10 @@ DefaultCommit<Impl>::commitInsts()
                 }
 
                 PC[tid] = nextPC[tid];
-#if ISA_HAS_DELAY_SLOT
                 nextPC[tid] = nextNPC[tid];
                 nextNPC[tid] = nextNPC[tid] + sizeof(TheISA::MachInst);
-#else
-                nextPC[tid] = nextPC[tid] + sizeof(TheISA::MachInst);
-#endif
+                microPC[tid] = nextMicroPC[tid];
+                nextMicroPC[tid] = microPC[tid] + 1;
 
 #if FULL_SYSTEM
                 int count = 0;
diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index b2b4645d2..59978a065 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -696,7 +696,7 @@ FullO3CPU<Impl>::removeThread(unsigned tid)
 
     // Squash Throughout Pipeline
     InstSeqNum squash_seq_num = commit.rob->readHeadInst(tid)->seqNum;
-    fetch.squash(0, sizeof(TheISA::MachInst), squash_seq_num, tid);
+    fetch.squash(0, sizeof(TheISA::MachInst), 0, squash_seq_num, tid);
     decode.squash(tid);
     rename.squash(squash_seq_num, tid);
     iew.squash(tid);
@@ -1152,6 +1152,20 @@ FullO3CPU<Impl>::setPC(Addr new_PC,unsigned tid)
 
 template <class Impl>
 uint64_t
+FullO3CPU<Impl>::readMicroPC(unsigned tid)
+{
+    return commit.readMicroPC(tid);
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::setMicroPC(Addr new_PC,unsigned tid)
+{
+    commit.setMicroPC(new_PC, tid);
+}
+
+template <class Impl>
+uint64_t
 FullO3CPU<Impl>::readNextPC(unsigned tid)
 {
     return commit.readNextPC(tid);
@@ -1179,6 +1193,20 @@ FullO3CPU<Impl>::setNextNPC(uint64_t val,unsigned tid)
 }
 
 template <class Impl>
+uint64_t
+FullO3CPU<Impl>::readNextMicroPC(unsigned tid)
+{
+    return commit.readNextMicroPC(tid);
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::setNextMicroPC(Addr new_PC,unsigned tid)
+{
+    commit.setNextMicroPC(new_PC, tid);
+}
+
+template <class Impl>
 typename FullO3CPU<Impl>::ListIt
 FullO3CPU<Impl>::addInst(DynInstPtr &inst)
 {
diff --git a/src/cpu/o3/cpu.hh b/src/cpu/o3/cpu.hh
index 4b247e6e3..bff78bf9e 100644
--- a/src/cpu/o3/cpu.hh
+++ b/src/cpu/o3/cpu.hh
@@ -433,22 +433,34 @@ class FullO3CPU : public BaseO3CPU
     void setArchFloatRegInt(int reg_idx, uint64_t val, unsigned tid);
 
     /** Reads the commit PC of a specific thread. */
-    uint64_t readPC(unsigned tid);
+    Addr readPC(unsigned tid);
 
     /** Sets the commit PC of a specific thread. */
     void setPC(Addr new_PC, unsigned tid);
 
+    /** Reads the commit micro PC of a specific thread. */
+    Addr readMicroPC(unsigned tid);
+
+    /** Sets the commmit micro PC of a specific thread. */
+    void setMicroPC(Addr new_microPC, unsigned tid);
+
     /** Reads the next PC of a specific thread. */
-    uint64_t readNextPC(unsigned tid);
+    Addr readNextPC(unsigned tid);
 
     /** Sets the next PC of a specific thread. */
-    void setNextPC(uint64_t val, unsigned tid);
+    void setNextPC(Addr val, unsigned tid);
 
     /** Reads the next NPC of a specific thread. */
-    uint64_t readNextNPC(unsigned tid);
+    Addr readNextNPC(unsigned tid);
 
     /** Sets the next NPC of a specific thread. */
-    void setNextNPC(uint64_t val, unsigned tid);
+    void setNextNPC(Addr val, unsigned tid);
+
+    /** Reads the commit next micro PC of a specific thread. */
+    Addr readNextMicroPC(unsigned tid);
+
+    /** Sets the commit next micro PC of a specific thread. */
+    void setNextMicroPC(Addr val, unsigned tid);
 
     /** Function to add instruction onto the head of the list of the
      *  instructions.  Used when new instructions are fetched.
diff --git a/src/cpu/o3/decode_impl.hh b/src/cpu/o3/decode_impl.hh
index c9d0a1885..ce6738456 100644
--- a/src/cpu/o3/decode_impl.hh
+++ b/src/cpu/o3/decode_impl.hh
@@ -273,6 +273,7 @@ DefaultDecode<Impl>::squash(DynInstPtr &inst, unsigned tid)
     ///explicitly for ISAs with delay slots.
     toFetch->decodeInfo[tid].nextNPC =
         inst->branchTarget() + sizeof(TheISA::MachInst);
+    toFetch->decodeInfo[tid].nextMicroPC = inst->readMicroPC();
 #if ISA_HAS_DELAY_SLOT
     toFetch->decodeInfo[tid].branchTaken = inst->readNextNPC() !=
         (inst->readNextPC() + sizeof(TheISA::MachInst));
@@ -735,7 +736,8 @@ DefaultDecode<Impl>::decodeInsts(unsigned tid)
                 // a check at the end
                 squash(inst, inst->threadNumber);
                 Addr target = inst->branchTarget();
-                inst->setPredTarg(target, target + sizeof(TheISA::MachInst));
+                //The micro pc after an instruction level branch should be 0
+                inst->setPredTarg(target, target + sizeof(TheISA::MachInst), 0);
                 break;
             }
         }
diff --git a/src/cpu/o3/fetch.hh b/src/cpu/o3/fetch.hh
index bb0057e7c..7645a226c 100644
--- a/src/cpu/o3/fetch.hh
+++ b/src/cpu/o3/fetch.hh
@@ -227,7 +227,7 @@ class DefaultFetch
      * @param next_NPC Used for ISAs which use delay slots.
      * @return Whether or not a branch was predicted as taken.
      */
-    bool lookupAndUpdateNextPC(DynInstPtr &inst, Addr &next_PC, Addr &next_NPC);
+    bool lookupAndUpdateNextPC(DynInstPtr &inst, Addr &next_PC, Addr &next_NPC, Addr &next_MicroPC);
 
     /**
      * Fetches the cache line that contains fetch_PC.  Returns any
@@ -242,12 +242,14 @@ class DefaultFetch
     bool fetchCacheLine(Addr fetch_PC, Fault &ret_fault, unsigned tid);
 
     /** Squashes a specific thread and resets the PC. */
-    inline void doSquash(const Addr &new_PC, const Addr &new_NPC, unsigned tid);
+    inline void doSquash(const Addr &new_PC, const Addr &new_NPC,
+                         const Addr &new_MicroPC, unsigned tid);
 
     /** Squashes a specific thread and resets the PC. Also tells the CPU to
      * remove any instructions between fetch and decode that should be sqaushed.
      */
     void squashFromDecode(const Addr &new_PC, const Addr &new_NPC,
+                          const Addr &new_MicroPC,
                           const InstSeqNum &seq_num, unsigned tid);
 
     /** Checks if a thread is stalled. */
@@ -263,6 +265,7 @@ class DefaultFetch
      * squash should be the commit stage.
      */
     void squash(const Addr &new_PC, const Addr &new_NPC,
+                const Addr &new_MicroPC,
                 const InstSeqNum &seq_num, unsigned tid);
 
     /** Ticks the fetch stage, processing all inputs signals and fetching
@@ -346,16 +349,12 @@ class DefaultFetch
     /** Per-thread fetch PC. */
     Addr PC[Impl::MaxThreads];
 
+    /** Per-thread fetch micro PC. */
+    Addr microPC[Impl::MaxThreads];
+
     /** Per-thread next PC. */
     Addr nextPC[Impl::MaxThreads];
 
-    /** Per-thread next Next PC.
-     *  This is not a real register but is used for
-     *  architectures that use a branch-delay slot.
-     *  (such as MIPS or Sparc)
-     */
-    Addr nextNPC[Impl::MaxThreads];
-
     /** Memory request used to access cache. */
     RequestPtr memReq[Impl::MaxThreads];
 
diff --git a/src/cpu/o3/fetch_impl.hh b/src/cpu/o3/fetch_impl.hh
index 25498c7f3..d1f38e38b 100644
--- a/src/cpu/o3/fetch_impl.hh
+++ b/src/cpu/o3/fetch_impl.hh
@@ -312,7 +312,7 @@ DefaultFetch<Impl>::initStage()
     for (int tid = 0; tid < numThreads; tid++) {
         PC[tid] = cpu->readPC(tid);
         nextPC[tid] = cpu->readNextPC(tid);
-        nextNPC[tid] = cpu->readNextNPC(tid);
+        microPC[tid] = cpu->readMicroPC(tid);
     }
 
     for (int tid=0; tid < numThreads; tid++) {
@@ -439,11 +439,7 @@ DefaultFetch<Impl>::takeOverFrom()
         stalls[i].commit = 0;
         PC[i] = cpu->readPC(i);
         nextPC[i] = cpu->readNextPC(i);
-#if ISA_HAS_DELAY_SLOT
-        nextNPC[i] = cpu->readNextNPC(i);
-#else
-        nextNPC[i] = nextPC[i] + sizeof(TheISA::MachInst);
-#endif
+        microPC[i] = cpu->readMicroPC(i);
         fetchStatus[i] = Running;
     }
     numInst = 0;
@@ -493,7 +489,7 @@ DefaultFetch<Impl>::switchToInactive()
 template <class Impl>
 bool
 DefaultFetch<Impl>::lookupAndUpdateNextPC(DynInstPtr &inst, Addr &next_PC,
-                                          Addr &next_NPC)
+                                          Addr &next_NPC, Addr &next_MicroPC)
 {
     // Do branch prediction check here.
     // A bit of a misnomer...next_PC is actually the current PC until
@@ -501,13 +497,22 @@ DefaultFetch<Impl>::lookupAndUpdateNextPC(DynInstPtr &inst, Addr &next_PC,
     bool predict_taken;
 
     if (!inst->isControl()) {
-        next_PC  = next_NPC;
-        next_NPC = next_NPC + instSize;
-        inst->setPredTarg(next_PC, next_NPC);
+        if (inst->isMicroOp() && !inst->isLastMicroOp()) {
+            next_MicroPC++;
+        } else {
+            next_PC  = next_NPC;
+            next_NPC = next_NPC + instSize;
+            next_MicroPC = 0;
+        }
+        inst->setPredTarg(next_PC, next_NPC, next_MicroPC);
         inst->setPredTaken(false);
         return false;
     }
 
+    //Assume for now that all control flow is to a different macroop which
+    //would reset the micro pc to 0.
+    next_MicroPC = 0;
+
     int tid = inst->threadNumber;
     Addr pred_PC = next_PC;
     predict_taken = branchPred.predict(inst, pred_PC, tid);
@@ -534,7 +539,7 @@ DefaultFetch<Impl>::lookupAndUpdateNextPC(DynInstPtr &inst, Addr &next_PC,
 #endif
 /*    DPRINTF(Fetch, "[tid:%i]: Branch predicted to go to %#x and then %#x.\n",
             tid, next_PC, next_NPC);*/
-    inst->setPredTarg(next_PC, next_NPC);
+    inst->setPredTarg(next_PC, next_NPC, next_MicroPC);
     inst->setPredTaken(predict_taken);
 
     ++fetchedBranches;
@@ -658,14 +663,14 @@ DefaultFetch<Impl>::fetchCacheLine(Addr fetch_PC, Fault &ret_fault, unsigned tid
 template <class Impl>
 inline void
 DefaultFetch<Impl>::doSquash(const Addr &new_PC,
-        const Addr &new_NPC, unsigned tid)
+        const Addr &new_NPC, const Addr &new_microPC, unsigned tid)
 {
     DPRINTF(Fetch, "[tid:%i]: Squashing, setting PC to: %#x, NPC to: %#x.\n",
             tid, new_PC, new_NPC);
 
     PC[tid] = new_PC;
     nextPC[tid] = new_NPC;
-    nextNPC[tid] = new_NPC + instSize;
+    microPC[tid] = new_microPC;
 
     // Clear the icache miss if it's outstanding.
     if (fetchStatus[tid] == IcacheWaitResponse) {
@@ -693,12 +698,12 @@ DefaultFetch<Impl>::doSquash(const Addr &new_PC,
 template<class Impl>
 void
 DefaultFetch<Impl>::squashFromDecode(const Addr &new_PC, const Addr &new_NPC,
-                                     const InstSeqNum &seq_num,
-                                     unsigned tid)
+                                     const Addr &new_MicroPC,
+                                     const InstSeqNum &seq_num, unsigned tid)
 {
     DPRINTF(Fetch, "[tid:%i]: Squashing from decode.\n",tid);
 
-    doSquash(new_PC, new_NPC, tid);
+    doSquash(new_PC, new_NPC, new_MicroPC, tid);
 
     // Tell the CPU to remove any instructions that are in flight between
     // fetch and decode.
@@ -774,11 +779,12 @@ DefaultFetch<Impl>::updateFetchStatus()
 template <class Impl>
 void
 DefaultFetch<Impl>::squash(const Addr &new_PC, const Addr &new_NPC,
+                           const Addr &new_MicroPC,
                            const InstSeqNum &seq_num, unsigned tid)
 {
     DPRINTF(Fetch, "[tid:%u]: Squash from commit.\n",tid);
 
-    doSquash(new_PC, new_NPC, tid);
+    doSquash(new_PC, new_NPC, new_MicroPC, tid);
 
     // Tell the CPU to remove any instructions that are not in the ROB.
     cpu->removeInstsNotInROB(tid);
@@ -893,6 +899,7 @@ DefaultFetch<Impl>::checkSignalsAndUpdate(unsigned tid)
         // In any case, squash.
         squash(fromCommit->commitInfo[tid].nextPC,
                fromCommit->commitInfo[tid].nextNPC,
+               fromCommit->commitInfo[tid].nextMicroPC,
                fromCommit->commitInfo[tid].doneSeqNum,
                tid);
 
@@ -948,6 +955,7 @@ DefaultFetch<Impl>::checkSignalsAndUpdate(unsigned tid)
             // Squash unless we're already squashing
             squashFromDecode(fromDecode->decodeInfo[tid].nextPC,
                              fromDecode->decodeInfo[tid].nextNPC,
+                             fromDecode->decodeInfo[tid].nextMicroPC,
                              fromDecode->decodeInfo[tid].doneSeqNum,
                              tid);
 
@@ -1002,9 +1010,9 @@ DefaultFetch<Impl>::fetch(bool &status_change)
     DPRINTF(Fetch, "Attempting to fetch from [tid:%i]\n", tid);
 
     // The current PC.
-    Addr &fetch_PC = PC[tid];
-
-    Addr &fetch_NPC = nextPC[tid];
+    Addr fetch_PC = PC[tid];
+    Addr fetch_NPC = nextPC[tid];
+    Addr fetch_MicroPC = microPC[tid];
 
     // Fault code for memory access.
     Fault fault = NoFault;
@@ -1063,6 +1071,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
 
     Addr next_PC = fetch_PC;
     Addr next_NPC = fetch_NPC;
+    Addr next_MicroPC = fetch_MicroPC;
 
     InstSeqNum inst_seq;
     MachInst inst;
@@ -1070,6 +1079,9 @@ DefaultFetch<Impl>::fetch(bool &status_change)
     // @todo: Fix this hack.
     unsigned offset = (fetch_PC & cacheBlkMask) & ~3;
 
+    StaticInstPtr staticInst = NULL;
+    StaticInstPtr macroop = NULL;
+
     if (fault == NoFault) {
         // If the read of the first instruction was successful, then grab the
         // instructions from the rest of the cache line and put them into the
@@ -1104,19 +1116,29 @@ DefaultFetch<Impl>::fetch(bool &status_change)
             // Make sure this is a valid index.
             assert(offset <= cacheBlkSize - instSize);
 
-            // Get the instruction from the array of the cache line.
-            inst = TheISA::gtoh(*reinterpret_cast<TheISA::MachInst *>
-                        (&cacheData[tid][offset]));
+            if (!macroop) {
+                // Get the instruction from the array of the cache line.
+                inst = TheISA::gtoh(*reinterpret_cast<TheISA::MachInst *>
+                            (&cacheData[tid][offset]));
 
-            predecoder.setTC(cpu->thread[tid]->getTC());
-            predecoder.moreBytes(fetch_PC, 0, inst);
+                predecoder.setTC(cpu->thread[tid]->getTC());
+                predecoder.moreBytes(fetch_PC, 0, inst);
 
-            ext_inst = predecoder.getExtMachInst();
+                ext_inst = predecoder.getExtMachInst();
+                staticInst = StaticInstPtr(ext_inst);
+                if (staticInst->isMacroOp())
+                    macroop = staticInst;
+            }
+            if (macroop) {
+                staticInst = macroop->fetchMicroOp(fetch_MicroPC);
+                if (staticInst->isLastMicroOp())
+                    macroop = NULL;
+            }
 
             // Create a new DynInst from the instruction fetched.
-            DynInstPtr instruction = new DynInst(ext_inst,
-                                                 fetch_PC, fetch_NPC,
-                                                 next_PC, next_NPC,
+            DynInstPtr instruction = new DynInst(staticInst,
+                                                 fetch_PC, fetch_NPC, fetch_MicroPC,
+                                                 next_PC, next_NPC, next_MicroPC,
                                                  inst_seq, cpu);
             instruction->setTid(tid);
 
@@ -1139,7 +1161,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
                                      instruction->readPC());
 
             ///FIXME This needs to be more robust in dealing with delay slots
-            lookupAndUpdateNextPC(instruction, next_PC, next_NPC);
+            lookupAndUpdateNextPC(instruction, next_PC, next_NPC, next_MicroPC);
             predicted_branch |= (next_PC != fetch_NPC);
 
             // Add instruction to the CPU's list of instructions.
@@ -1157,6 +1179,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
             // Move to the next instruction, unless we have a branch.
             fetch_PC = next_PC;
             fetch_NPC = next_NPC;
+            fetch_MicroPC = next_MicroPC;
 
             if (instruction->isQuiesce()) {
                 DPRINTF(Fetch, "Quiesce instruction encountered, halting fetch!",
@@ -1167,7 +1190,8 @@ DefaultFetch<Impl>::fetch(bool &status_change)
                 break;
             }
 
-            offset += instSize;
+            if (!macroop)
+                offset += instSize;
         }
 
         if (offset >= cacheBlkSize) {
@@ -1191,7 +1215,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
     if (fault == NoFault) {
         PC[tid] = next_PC;
         nextPC[tid] = next_NPC;
-        nextNPC[tid] = next_NPC + instSize;
+        microPC[tid] = next_MicroPC;
         DPRINTF(Fetch, "[tid:%i]: Setting PC to %08p.\n", tid, next_PC);
     } else {
         // We shouldn't be in an icache miss and also have a fault (an ITB
@@ -1210,8 +1234,9 @@ DefaultFetch<Impl>::fetch(bool &status_change)
         // We will use a nop in order to carry the fault.
         ext_inst = TheISA::NoopMachInst;
 
+        StaticInstPtr staticInst = new StaticInst(ext_inst);
         // Create a new DynInst from the dummy nop.
-        DynInstPtr instruction = new DynInst(ext_inst,
+        DynInstPtr instruction = new DynInst(staticInst,
                                              fetch_PC, fetch_NPC,
                                              next_PC, next_NPC,
                                              inst_seq, cpu);
diff --git a/src/cpu/o3/iew_impl.hh b/src/cpu/o3/iew_impl.hh
index 050785818..399c44909 100644
--- a/src/cpu/o3/iew_impl.hh
+++ b/src/cpu/o3/iew_impl.hh
@@ -454,6 +454,7 @@ DefaultIEW<Impl>::squashDueToBranch(DynInstPtr &inst, unsigned tid)
 #endif
     toCommit->nextPC[tid] = inst->readNextPC();
     toCommit->nextNPC[tid] = inst->readNextNPC();
+    toCommit->nextMicroPC[tid] = inst->readNextMicroPC();
 
     toCommit->includeSquashInst[tid] = false;
 
diff --git a/src/cpu/o3/rename_impl.hh b/src/cpu/o3/rename_impl.hh
index 6e7180b1e..d78de2c87 100644
--- a/src/cpu/o3/rename_impl.hh
+++ b/src/cpu/o3/rename_impl.hh
@@ -963,6 +963,7 @@ DefaultRename<Impl>::renameSrcRegs(DynInstPtr &inst,unsigned tid)
             // Floating point and Miscellaneous registers need their indexes
             // adjusted to account for the expanded number of flattened int regs.
             flat_src_reg = src_reg - TheISA::FP_Base_DepTag + TheISA::NumIntRegs;
+            DPRINTF(Rename, "Adjusting reg index from %d to %d.\n", src_reg, flat_src_reg);
         }
 
         inst->flattenSrcReg(src_idx, flat_src_reg);
@@ -979,9 +980,11 @@ DefaultRename<Impl>::renameSrcRegs(DynInstPtr &inst,unsigned tid)
 
         // See if the register is ready or not.
         if (scoreboard->getReg(renamed_reg) == true) {
-            DPRINTF(Rename, "[tid:%u]: Register is ready.\n", tid);
+            DPRINTF(Rename, "[tid:%u]: Register %d is ready.\n", tid, renamed_reg);
 
             inst->markSrcRegReady(src_idx);
+        } else {
+            DPRINTF(Rename, "[tid:%u]: Register %d is not ready.\n", tid, renamed_reg);
         }
 
         ++renameRenameLookups;
@@ -1008,6 +1011,7 @@ DefaultRename<Impl>::renameDestRegs(DynInstPtr &inst,unsigned tid)
             // Floating point and Miscellaneous registers need their indexes
             // adjusted to account for the expanded number of flattened int regs.
             flat_dest_reg = dest_reg - TheISA::FP_Base_DepTag + TheISA::NumIntRegs;
+            DPRINTF(Rename, "Adjusting reg index from %d to %d.\n", dest_reg, flat_dest_reg);
         }
 
         inst->flattenDestReg(dest_idx, flat_dest_reg);
diff --git a/src/cpu/o3/sparc/dyn_inst.hh b/src/cpu/o3/sparc/dyn_inst.hh
index 72242b161..a7ab6cd79 100644
--- a/src/cpu/o3/sparc/dyn_inst.hh
+++ b/src/cpu/o3/sparc/dyn_inst.hh
@@ -56,8 +56,14 @@ class SparcDynInst : public BaseDynInst<Impl>
 
   public:
     /** BaseDynInst constructor given a binary instruction. */
-    SparcDynInst(TheISA::ExtMachInst inst, Addr PC, Addr NPC,
-            Addr Pred_PC, Addr Pred_NPC, InstSeqNum seq_num, O3CPU *cpu);
+    SparcDynInst(StaticInstPtr staticInst, Addr PC, Addr NPC, Addr microPC,
+            Addr Pred_PC, Addr Pred_NPC, Addr Pred_MicroPC,
+            InstSeqNum seq_num, O3CPU *cpu);
+
+    /** BaseDynInst constructor given a binary instruction. */
+    SparcDynInst(TheISA::ExtMachInst inst, Addr PC, Addr NPC, Addr microPC,
+            Addr Pred_PC, Addr Pred_NPC, Addr Pred_MicroPC,
+            InstSeqNum seq_num, O3CPU *cpu);
 
     /** BaseDynInst constructor given a static inst pointer. */
     SparcDynInst(StaticInstPtr &_staticInst);
diff --git a/src/cpu/o3/sparc/dyn_inst_impl.hh b/src/cpu/o3/sparc/dyn_inst_impl.hh
index c4d30b6f4..6bfe97717 100644
--- a/src/cpu/o3/sparc/dyn_inst_impl.hh
+++ b/src/cpu/o3/sparc/dyn_inst_impl.hh
@@ -31,10 +31,23 @@
 #include "cpu/o3/sparc/dyn_inst.hh"
 
 template <class Impl>
+SparcDynInst<Impl>::SparcDynInst(StaticInstPtr staticInst,
+        Addr PC, Addr NPC, Addr microPC,
+        Addr Pred_PC, Addr Pred_NPC, Addr Pred_MicroPC,
+        InstSeqNum seq_num, O3CPU *cpu)
+    : BaseDynInst<Impl>(staticInst, PC, NPC, microPC,
+            Pred_PC, Pred_NPC, Pred_MicroPC, seq_num, cpu)
+{
+    initVars();
+}
+
+template <class Impl>
 SparcDynInst<Impl>::SparcDynInst(TheISA::ExtMachInst inst,
-        Addr PC, Addr NPC, Addr Pred_PC, Addr Pred_NPC,
+        Addr PC, Addr NPC, Addr microPC,
+        Addr Pred_PC, Addr Pred_NPC, Addr Pred_MicroPC,
         InstSeqNum seq_num, O3CPU *cpu)
-    : BaseDynInst<Impl>(inst, PC, NPC, Pred_PC, Pred_NPC, seq_num, cpu)
+    : BaseDynInst<Impl>(inst, PC, NPC, microPC,
+            Pred_PC, Pred_NPC, Pred_MicroPC, seq_num, cpu)
 {
     initVars();
 }