2 files changed, 37 insertions, 7 deletions

diff --git a/src/cpu/checker/cpu.hh b/src/cpu/checker/cpu.hh
index 6d6ae1e0a..737b4b5d4 100644
--- a/src/cpu/checker/cpu.hh
+++ b/src/cpu/checker/cpu.hh
@@ -102,6 +102,7 @@ class CheckerCPU : public BaseCPU
         Process *process;
 #endif
         bool exitOnError;
+        bool updateOnError;
         bool warnOnlyOnLoadError;
     };
 
@@ -148,7 +149,7 @@ class CheckerCPU : public BaseCPU
 
     union Result {
         uint64_t integer;
-        float fp;
+//        float fp;
         double dbl;
     };
 
@@ -269,7 +270,7 @@ class CheckerCPU : public BaseCPU
     {
         int reg_idx = si->destRegIdx(idx) - TheISA::FP_Base_DepTag;
         thread->setFloatReg(reg_idx, val);
-        result.fp = val;
+        result.dbl = (double)val;
     }
 
     void setFloatRegBits(const StaticInst *si, int idx, FloatRegBits val,
@@ -318,7 +319,7 @@ class CheckerCPU : public BaseCPU
         return thread->setMiscRegWithEffect(misc_reg, val);
     }
 
-    void recordPCChange(uint64_t val) { changedPC = true; }
+    void recordPCChange(uint64_t val) { changedPC = true; newPC = val; }
     void recordNextPCChange(uint64_t val) { changedNextPC = true; }
 
     bool translateInstReq(Request *req);
@@ -360,6 +361,7 @@ class CheckerCPU : public BaseCPU
     uint64_t newPC;
     bool changedNextPC;
     bool exitOnError;
+    bool updateOnError;
     bool warnOnlyOnLoadError;
 
     InstSeqNum youngestSN;
@@ -376,7 +378,7 @@ class Checker : public CheckerCPU
 {
   public:
     Checker(Params *p)
-        : CheckerCPU(p)
+        : CheckerCPU(p), updateThisCycle(false), unverifiedInst(NULL)
     { }
 
     void switchOut();
@@ -393,12 +395,19 @@ class Checker : public CheckerCPU
   private:
     void handleError(DynInstPtr &inst)
     {
-        if (exitOnError)
+        if (exitOnError) {
             dumpAndExit(inst);
+        } else if (updateOnError) {
+            updateThisCycle = true;
+        }
     }
 
     void dumpAndExit(DynInstPtr &inst);
 
+    bool updateThisCycle;
+
+    DynInstPtr unverifiedInst;
+
     std::list<DynInstPtr> instList;
     typedef typename std::list<DynInstPtr>::iterator InstListIt;
     void dumpInsts();
diff --git a/src/cpu/checker/cpu_impl.hh b/src/cpu/checker/cpu_impl.hh
index 81f97726c..3bb81c4b9 100644
--- a/src/cpu/checker/cpu_impl.hh
+++ b/src/cpu/checker/cpu_impl.hh
@@ -94,6 +94,8 @@ Checker<DynInstPtr>::verify(DynInstPtr &completed_inst)
         }
     }
 
+    unverifiedInst = inst;
+
     // Try to check all instructions that are completed, ending if we
     // run out of instructions to check or if an instruction is not
     // yet completed.
@@ -171,7 +173,7 @@ Checker<DynInstPtr>::verify(DynInstPtr &completed_inst)
                 thread->setPC(thread->readNextPC());
                 thread->setNextPC(thread->readNextPC() + sizeof(MachInst));
 
-                return;
+                break;
             } else {
                 // The instruction is carrying an ITB fault.  Handle
                 // the fault and see if our results match the CPU on
@@ -220,7 +222,8 @@ Checker<DynInstPtr>::verify(DynInstPtr &completed_inst)
 
             thread->funcExeInst++;
 
-            fault = curStaticInst->execute(this, NULL);
+            if (!inst->isUnverifiable())
+                fault = curStaticInst->execute(this, NULL);
 
             // Checks to make sure instrution results are correct.
             validateExecution(inst);
@@ -289,6 +292,7 @@ Checker<DynInstPtr>::verify(DynInstPtr &completed_inst)
             break;
         }
     }
+    unverifiedInst = NULL;
 }
 
 template <class DynInstPtr>
@@ -395,6 +399,23 @@ template <class DynInstPtr>
 void
 Checker<DynInstPtr>::validateState()
 {
+    if (updateThisCycle) {
+        warn("%lli: Instruction PC %#x results didn't match up, copying all "
+             "registers from main CPU", curTick, unverifiedInst->readPC());
+        // Heavy-weight copying of all registers
+        cpuXC->copyArchRegs(unverifiedInst->xcBase());
+        // Also advance the PC.  Hopefully no PC-based events happened.
+#if THE_ISA != MIPS_ISA
+        // go to the next instruction
+        cpuXC->setPC(cpuXC->readNextPC());
+        cpuXC->setNextPC(cpuXC->readNextPC() + sizeof(MachInst));
+#else
+        // go to the next instruction
+        cpuXC->setPC(cpuXC->readNextPC());
+        cpuXC->setNextPC(cpuXC->readNextNPC());
+        cpuXC->setNextNPC(cpuXC->readNextNPC() + sizeof(MachInst));
+#endif
+        updateThisCycle = false;
 }
 
 template <class DynInstPtr>