Move libFuzzer to compiler_rt.

Resulting library binaries will be named libclang_rt.fuzzer*, and will
be placed in Clang toolchain, allowing redistribution.

Differential Revision: https://reviews.llvm.org/D36908

llvm-svn: 311407
diff --git a/compiler-rt/test/fuzzer/CounterTest.cpp b/compiler-rt/test/fuzzer/CounterTest.cpp
new file mode 100644
index 0000000..4917934
--- /dev/null
+++ b/compiler-rt/test/fuzzer/CounterTest.cpp
@@ -0,0 +1,18 @@
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+
+// Test for a fuzzer: must find the case where a particular basic block is
+// executed many times.
+#include <iostream>
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+  int Num = 0;
+  for (size_t i = 0; i < Size; i++)
+    if (Data[i] == 'A' + i)
+      Num++;
+  if (Num >= 4) {
+    std::cerr <<  "BINGO!\n";
+    exit(1);
+  }
+  return 0;
+}