assert(0) -> LLVM_UNREACHABLE.
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75379 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/ValueMapper.cpp b/lib/Transforms/Utils/ValueMapper.cpp
index 21b3a22..951d24f 100644
--- a/lib/Transforms/Utils/ValueMapper.cpp
+++ b/lib/Transforms/Utils/ValueMapper.cpp
@@ -20,6 +20,7 @@
 #include "llvm/LLVMContext.h"
 #include "llvm/MDNode.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/ErrorHandling.h"
 using namespace llvm;
 
 Value *llvm::MapValue(const Value *V, ValueMapTy &VM, LLVMContext *Context) {
@@ -126,7 +127,7 @@
       return VM[V] = C;
 
     } else {
-      assert(0 && "Unknown type of constant!");
+      LLVM_UNREACHABLE("Unknown type of constant!");
     }
   }