afl-unicorn-common.h

/*
   american fuzzy lop++ - unicorn instrumentation
   ----------------------------------------------

   Originally written by Andrew Griffiths <agriffiths@google.com> and
                         Michal Zalewski

   Adapted for afl-unicorn by Dominik Maier <mail@dmnk.co>

   CompareCoverage and NeverZero counters by Andrea Fioraldi
                                  <andreafioraldi@gmail.com>

   Copyright 2015, 2016, 2017 Google Inc. All rights reserved.
   Copyright 2019 AFLplusplus Project. All rights reserved.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at:

     http://www.apache.org/licenses/LICENSE-2.0

   This code is a shim patched into the separately-distributed source
   code of Unicorn 1.0.1. It leverages the built-in QEMU tracing functionality
   to implement AFL-style instrumentation and to take care of the remaining
   parts of the AFL fork server logic.

   The resulting libunicorn binary is essentially a standalone instrumentation
   tool; for an example of how to leverage it for other purposes, you can
   have a look at afl-showmap.c.

 */

#include "config.h"
#include "types.h"

/* NeverZero */

#if (defined(__x86_64__) || defined(__i386__)) && defined(AFL_QEMU_NOT_ZERO)
#define INC_AFL_AREA(loc)           \
  asm volatile(                     \
      "addb $1, (%0, %1, 1)\n"      \
      "adcb $0, (%0, %1, 1)\n"      \
      : /* no out */                \
      : "r"(afl_area_ptr), "r"(loc) \
      : "memory", "eax")
#else
#define INC_AFL_AREA(loc) afl_area_ptr[loc]++
#endif