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
|
/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "Test.h"
#include "SkSafeMath.h"
DEF_TEST(SafeMath, r) {
size_t max = std::numeric_limits<size_t>::max();
{
size_t halfMax = max >> 1;
size_t halfMaxPlus1 = halfMax + 1;
SkSafeMath safe;
REPORTER_ASSERT(r, safe.add(halfMax, halfMax) == 2 * halfMax);
REPORTER_ASSERT(r, safe);
REPORTER_ASSERT(r, safe.add(halfMax, halfMaxPlus1) == max);
REPORTER_ASSERT(r, safe);
REPORTER_ASSERT(r, safe.add(max, 1) == 0);
REPORTER_ASSERT(r, !safe);
}
{
SkSafeMath safe;
(void) safe.add(max, max);
REPORTER_ASSERT(r, !safe);
}
{
size_t bits = (sizeof(size_t) * 8);
size_t halfBits = bits / 2;
size_t sqrtMax = max >> halfBits;
size_t sqrtMaxPlus1 = sqrtMax + 1;
SkSafeMath safe;
REPORTER_ASSERT(r, safe.mul(sqrtMax, sqrtMax) == sqrtMax * sqrtMax);
REPORTER_ASSERT(r, safe);
REPORTER_ASSERT(r, safe.mul(sqrtMax, sqrtMaxPlus1) == sqrtMax << halfBits);
REPORTER_ASSERT(r, safe);
REPORTER_ASSERT(r, safe.mul(sqrtMaxPlus1, sqrtMaxPlus1) == 0);
REPORTER_ASSERT(r, !safe);
}
{
SkSafeMath safe;
(void) safe.mul(max, max);
REPORTER_ASSERT(r, !safe);
}
}
|
