1/*
2 * Copyright 2016-present Facebook, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#pragma once
18
19#if defined(_WIN32) && !defined(__clang__)
20#include <assert.h>
21#include <folly/Portability.h>
22#include <intrin.h>
23#include <stdint.h>
24
25namespace folly {
26namespace portability {
27namespace detail {
28void call_flush_instruction_cache_self_pid(void* begin, size_t size);
29}
30} // namespace portability
31} // namespace folly
32
33FOLLY_ALWAYS_INLINE void __builtin___clear_cache(char* begin, char* end) {
34 if (folly::kIsArchAmd64) {
35 // x86_64 doesn't require the instruction cache to be flushed after
36 // modification.
37 } else {
38 // Default to flushing it for everything else, such as ARM.
39 folly::portability::detail::call_flush_instruction_cache_self_pid(
40 static_cast<void*>(begin), static_cast<size_t>(end - begin));
41 }
42}
43
44FOLLY_ALWAYS_INLINE int __builtin_clz(unsigned int x) {
45 unsigned long index;
46 return int(_BitScanReverse(&index, (unsigned long)x) ? 31 - index : 32);
47}
48
49FOLLY_ALWAYS_INLINE int __builtin_clzl(unsigned long x) {
50 return __builtin_clz((unsigned int)x);
51}
52
53FOLLY_ALWAYS_INLINE int __builtin_clzll(unsigned long long x) {
54 unsigned long index;
55 return int(_BitScanReverse64(&index, x) ? 63 - index : 64);
56}
57
58FOLLY_ALWAYS_INLINE int __builtin_ctz(unsigned int x) {
59 unsigned long index;
60 return int(_BitScanForward(&index, (unsigned long)x) ? index : 32);
61}
62
63FOLLY_ALWAYS_INLINE int __builtin_ctzl(unsigned long x) {
64 return __builtin_ctz((unsigned int)x);
65}
66
67FOLLY_ALWAYS_INLINE int __builtin_ctzll(unsigned long long x) {
68 unsigned long index;
69 return int(_BitScanForward64(&index, x) ? index : 64);
70}
71
72FOLLY_ALWAYS_INLINE int __builtin_ffs(int x) {
73 unsigned long index;
74 return int(_BitScanForward(&index, (unsigned long)x) ? index + 1 : 0);
75}
76
77FOLLY_ALWAYS_INLINE int __builtin_ffsl(long x) {
78 return __builtin_ffs(int(x));
79}
80
81FOLLY_ALWAYS_INLINE int __builtin_ffsll(long long x) {
82 unsigned long index;
83 return int(_BitScanForward64(&index, (unsigned long long)x) ? index + 1 : 0);
84}
85
86FOLLY_ALWAYS_INLINE int __builtin_popcount(unsigned int x) {
87 return int(__popcnt(x));
88}
89
90FOLLY_ALWAYS_INLINE int __builtin_popcountl(unsigned long x) {
91 static_assert(sizeof(x) == 4, "");
92 return int(__popcnt(x));
93}
94
95FOLLY_ALWAYS_INLINE int __builtin_popcountll(unsigned long long x) {
96 return int(__popcnt64(x));
97}
98
99FOLLY_ALWAYS_INLINE void* __builtin_return_address(unsigned int frame) {
100 // I really hope frame is zero...
101 (void)frame;
102 assert(frame == 0);
103 return _ReturnAddress();
104}
105#endif
106