// Recursion depth should be equal or greater than the RSB size, but not
// excessively high because of the possibility of stack overflow.
constexpr size_t kRecursionDepth = 64;

// Modular function pointers that provide different functionality in the
// same-address-space and cross-address-space version. We use this design,
// because the same-address-space version works everywhere including on systems
// that do not allow forced pinning of processes to cores (e.g. MacOS), the
// cross-address-space version is Linux only.
extern void (*return_true_base_case)();
extern void (*return_false_base_case)();

// Global variables used to avoid passing parameters through recursive function
// calls. Since we flush whole stack frames from the cache, it is important not
// to store on stack any data that might be affected by being flushed from
// cache.
extern size_t current_offset;
extern const std::array<BigByte, 256> *oracle_ptr;

bool ReturnsFalse(int counter);
char Ret2specLeakByte();