ARM: Make the ARM native tracer stop M5 if control diverges.

If the control flow of M5's executable and statetrace's target process get out
of sync even a little, there will be a LOT of output, very little of which
will be useful. There's also almost no hope for recovery. In those cases, we
might as well give up and not generate a huge, mostly worthless trace file.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/arch/arm/nativetrace.cc b/src/arch/arm/nativetrace.cc
index 90c5e5c25..1ad9e1a19 100644
--- a/src/arch/arm/nativetrace.cc
+++ b/src/arch/arm/nativetrace.cc
@@ -162,6 +162,11 @@ Trace::ArmNativeTrace::check(NativeTraceRecord *record)
         }
         assert(inst);
         record->traceInst(inst, ran);
+
+        bool pcError = (mState.newState[STATE_PC] !=
+                        nState.newState[STATE_PC]);
+        if (stopOnPCError && pcError)
+            panic("Native trace detected an error in control flow!");
     }
 }