Added support for unsigned comparisons

Rationale: even though not directly supported in input graph,
           having the ability to express unsigned comparisons
           in HIR is useful for all sorts of optimizations.

Change-Id: I4543c96a8c1895c3d33aaf85685afbf80fe27d72
diff --git a/compiler/optimizing/induction_var_analysis.cc b/compiler/optimizing/induction_var_analysis.cc
index cf0f349..8968a44 100644
--- a/compiler/optimizing/induction_var_analysis.cc
+++ b/compiler/optimizing/induction_var_analysis.cc
@@ -650,8 +650,7 @@
       case kCondLE: return lower_value <= upper_value;
       case kCondGT: return lower_value >  upper_value;
       case kCondGE: return lower_value >= upper_value;
-      case kCondEQ:
-      case kCondNE: LOG(FATAL) << "CONDITION UNREACHABLE";
+      default:      LOG(FATAL) << "CONDITION UNREACHABLE";
     }
   }
   return false;  // not certain, may be untaken
@@ -680,8 +679,8 @@
           (IsIntAndGet(upper_expr, &value) && value >= (min - stride_value - 1));
     case kCondGE:
       return (IsIntAndGet(upper_expr, &value) && value >= (min - stride_value));
-    case kCondEQ:
-    case kCondNE: LOG(FATAL) << "CONDITION UNREACHABLE";
+    default:
+      LOG(FATAL) << "CONDITION UNREACHABLE";
   }
   return false;  // not certain, may be infinite
 }