1 files changed, 56 insertions, 0 deletions
diff --git a/lib/Fuzzer/test/CallerCalleeTest.cpp b/lib/Fuzzer/test/CallerCalleeTest.cpp
new file mode 100644
index 000000000000..150b2fc04058
--- /dev/null
+++ b/lib/Fuzzer/test/CallerCalleeTest.cpp
@@ -0,0 +1,56 @@
+// Simple test for a fuzzer.
+// Try to find the target using the indirect caller-callee pairs.
+#include <cstdint>
+#include <cstdlib>
+#include <cstddef>
+#include <cstring>
+#include <iostream>
+
+typedef void (*F)();
+static F t[256];
+
+void f34() {
+  std::cerr << "BINGO\n";
+  exit(1);
+}
+void f23() { t[(unsigned)'d'] = f34;}
+void f12() { t[(unsigned)'c'] = f23;}
+void f01() { t[(unsigned)'b'] = f12;}
+void f00() {}
+
+static F t0[256] = {
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+  f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
+};
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+  if (Size < 4) return 0;
+  // Spoof the counters.
+  for (int i = 0; i < 200; i++) {
+    f23();
+    f12();
+    f01();
+  }
+  memcpy(t, t0, sizeof(t));
+  t[(unsigned)'a'] = f01;
+  t[Data[0]]();
+  t[Data[1]]();
+  t[Data[2]]();
+  t[Data[3]]();
+  return 0;
+}
+