Remove dead code. Improve llvm_unreachable text. Simplify some control flow.

llvm-svn: 150918
diff --git a/llvm/lib/ExecutionEngine/Interpreter/Execution.cpp b/llvm/lib/ExecutionEngine/Interpreter/Execution.cpp
index ac4c49f..3dce3b3 100644
--- a/llvm/lib/ExecutionEngine/Interpreter/Execution.cpp
+++ b/llvm/lib/ExecutionEngine/Interpreter/Execution.cpp
@@ -1235,7 +1235,7 @@
     break;
   default:
     dbgs() << "Unhandled ConstantExpr: " << *CE << "\n";
-    llvm_unreachable(0);
+    llvm_unreachable("Unhandled ConstantExpr");
   }
   return Dest;
 }
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
index 75e4f71..4553ef4 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
@@ -34,7 +34,6 @@
     return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value,
                                 isPCRel, Type, Size, Addend);
   }
-  llvm_unreachable("");
 }
 
 bool RuntimeDyldMachO::