[libFuzzer] use the indirect caller-callee counter as an independent search heuristic
llvm-svn: 251078
diff --git a/llvm/lib/Fuzzer/test/CallerCalleeTest.cpp b/llvm/lib/Fuzzer/test/CallerCalleeTest.cpp
new file mode 100644
index 0000000..150b2fc0
--- /dev/null
+++ b/llvm/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;
+}
+