forked from v8/v8
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathbits.cc
More file actions
53 lines (39 loc) · 1.26 KB
/
Copy pathbits.cc
File metadata and controls
53 lines (39 loc) · 1.26 KB
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
// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/base/bits.h"
#include <limits>
#include "src/base/logging.h"
namespace v8 {
namespace base {
namespace bits {
uint32_t RoundUpToPowerOfTwo32(uint32_t value) {
DCHECK_LE(value, 0x80000000u);
value = value - 1;
value = value | (value >> 1);
value = value | (value >> 2);
value = value | (value >> 4);
value = value | (value >> 8);
value = value | (value >> 16);
return value + 1;
}
int32_t SignedMulHigh32(int32_t lhs, int32_t rhs) {
int64_t const value = static_cast<int64_t>(lhs) * static_cast<int64_t>(rhs);
return bit_cast<int32_t, uint32_t>(bit_cast<uint64_t>(value) >> 32u);
}
int32_t SignedMulHighAndAdd32(int32_t lhs, int32_t rhs, int32_t acc) {
return bit_cast<int32_t>(bit_cast<uint32_t>(acc) +
bit_cast<uint32_t>(SignedMulHigh32(lhs, rhs)));
}
int32_t SignedDiv32(int32_t lhs, int32_t rhs) {
if (rhs == 0) return 0;
if (rhs == -1) return -lhs;
return lhs / rhs;
}
int32_t SignedMod32(int32_t lhs, int32_t rhs) {
if (rhs == 0 || rhs == -1) return 0;
return lhs % rhs;
}
} // namespace bits
} // namespace base
} // namespace v8