1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
#include "src/__support/CPP/bit.h"
#include "src/__support/UInt.h"
#include "src/string/memory_utils/inline_memcpy.h"
using namespace LIBC_NAMESPACE;
// Helper function when using gdb / lldb to set a breakpoint and inspect values.
template <typename T> void debug_and_trap(const char *msg, T a, T b) {
__builtin_trap();
}
#define DEBUG_AND_TRAP()
#define TEST_BINOP(OP) \
if ((a OP b) != (static_cast<T>(BigInt(a) OP BigInt(b)))) \
debug_and_trap(#OP, a, b);
#define TEST_SHIFTOP(OP) \
if ((a OP b) != (static_cast<T>(BigInt(a) OP b))) \
debug_and_trap(#OP, a, b);
#define TEST_FUNCTION(FUN) \
if (FUN(a) != FUN(BigInt(a))) \
debug_and_trap(#FUN, a, b);
// Test that basic arithmetic operations of BigInt behave like their scalar
// counterparts.
template <typename T, typename BigInt> void run_tests(T a, T b) {
TEST_BINOP(+)
TEST_BINOP(-)
TEST_BINOP(*)
if (b != 0)
TEST_BINOP(/)
if (b >= 0 && b < cpp::numeric_limits<T>::digits) {
TEST_SHIFTOP(<<)
TEST_SHIFTOP(>>)
}
if constexpr (!BigInt::SIGNED) {
TEST_FUNCTION(cpp::has_single_bit)
TEST_FUNCTION(cpp::countr_zero)
TEST_FUNCTION(cpp::countl_zero)
TEST_FUNCTION(cpp::countl_one)
TEST_FUNCTION(cpp::countr_one)
}
}
// Reads a T from libfuzzer data.
template <typename T> T read(const uint8_t *data, size_t &remainder) {
T out = 0;
constexpr size_t T_SIZE = sizeof(T);
const size_t copy_size = remainder < T_SIZE ? remainder : T_SIZE;
inline_memcpy(&out, data, copy_size);
remainder -= copy_size;
return out;
}
template <typename T, typename BigInt>
void run_tests(const uint8_t *data, size_t size) {
const auto a = read<T>(data, size);
const auto b = read<T>(data, size);
run_tests<T, BigInt>(a, b);
}
extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
// unsigned
run_tests<uint64_t, BigInt<64, false, uint16_t>>(data, size);
// signed
run_tests<int64_t, BigInt<64, true, uint16_t>>(data, size);
return 0;
}
|
