[PowerPC] Fix switch warnings from r183841.

Introducing PRED_BAD caused some unexpected warnings that are now
suppressed.

llvm-svn: 183854
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
index 853e505..1c69a0b 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
@@ -18,6 +18,7 @@
 
 PPC::Predicate PPC::InvertPredicate(PPC::Predicate Opcode) {
   switch (Opcode) {
+  default: llvm_unreachable("Unknown PPC branch opcode!");
   case PPC::PRED_EQ: return PPC::PRED_NE;
   case PPC::PRED_NE: return PPC::PRED_EQ;
   case PPC::PRED_LT: return PPC::PRED_GE;
@@ -27,11 +28,11 @@
   case PPC::PRED_NU: return PPC::PRED_UN;
   case PPC::PRED_UN: return PPC::PRED_NU;
   }
-  llvm_unreachable("Unknown PPC branch opcode!");
 }
 
 PPC::Predicate PPC::getSwappedPredicate(PPC::Predicate Opcode) {
   switch (Opcode) {
+  default: llvm_unreachable("Unknown PPC branch opcode!");
   case PPC::PRED_EQ: return PPC::PRED_EQ;
   case PPC::PRED_NE: return PPC::PRED_NE;
   case PPC::PRED_LT: return PPC::PRED_GT;
@@ -41,6 +42,5 @@
   case PPC::PRED_NU: return PPC::PRED_NU;
   case PPC::PRED_UN: return PPC::PRED_UN;
   }
-  llvm_unreachable("Unknown PPC branch opcode!");
 }