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/Target/ARM/ARMConstantIslandPass.cpp b/lib/Target/ARM/ARMConstantIslandPass.cpp
index 34c9d70..1f2376e 100644
--- a/lib/Target/ARM/ARMConstantIslandPass.cpp
+++ b/lib/Target/ARM/ARMConstantIslandPass.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Statistic.h"
@@ -448,7 +449,7 @@
               Bits = 8;  // Taking the address of a CP entry.
               break;
             }
-            assert(0 && "Unknown addressing mode for CP reference!");
+            LLVM_UNREACHABLE("Unknown addressing mode for CP reference!");
           case ARMII::AddrMode1: // AM1: 8 bits << 2
             Bits = 8;
             Scale = 4;  // Taking the address of a CP entry.