1// Copyright 2017 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef V8_REGLIST_H_
6#define V8_REGLIST_H_
7
8#include <cstdint>
9
10#include "src/base/bits.h"
11#include "src/base/template-utils.h"
12
13namespace v8 {
14namespace internal {
15
16// Register configurations.
17#if V8_TARGET_ARCH_ARM64
18typedef uint64_t RegList;
19#else
20typedef uint32_t RegList;
21#endif
22
23// Get the number of registers in a given register list.
24constexpr int NumRegs(RegList list) {
25 return base::bits::CountPopulation(list);
26}
27
28// Combine two RegLists by building the union of the contained registers.
29// Implemented as a Functor to pass it to base::fold even on gcc < 5 (see
30// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52892).
31// TODO(clemensh): Remove this once we require gcc >= 5.0.
32struct CombineRegListsFunctor {
33 constexpr RegList operator()(RegList list1, RegList list2) const {
34 return list1 | list2;
35 }
36};
37
38// Combine several RegLists by building the union of the contained registers.
39template <typename... RegLists>
40constexpr RegList CombineRegLists(RegLists... lists) {
41 return base::fold(CombineRegListsFunctor{}, 0, lists...);
42}
43
44} // namespace internal
45} // namespace v8
46
47#endif // V8_REGLIST_H_
48