Exception work clean up.

Change-Id: Ide71ba25ea70b39651f80d9ff469019898a929e6
diff --git a/src/context_arm.cc b/src/context_arm.cc
index 85ada9d..0d25278 100644
--- a/src/context_arm.cc
+++ b/src/context_arm.cc
@@ -9,6 +9,7 @@
 
 ArmContext::ArmContext() {
 #ifndef NDEBUG
+  // Initialize registers with easy to spot debug values
   for (int i=0; i < 16; i++) {
     gprs_[i] = 0xEBAD6070+i;
   }