1//===-- Signposts.cpp - Interval debug annotations ------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "llvm/Support/Signposts.h"
10#include "llvm/ADT/StringRef.h"
11#include "llvm/Config/config.h"
12
13#if LLVM_SUPPORT_XCODE_SIGNPOSTS
14#include "llvm/ADT/DenseMap.h"
15#include "llvm/Support/Mutex.h"
16#include <Availability.h>
17#include <os/signpost.h>
18#endif // if LLVM_SUPPORT_XCODE_SIGNPOSTS
19
20using namespace llvm;
21
22#if LLVM_SUPPORT_XCODE_SIGNPOSTS
23#define SIGNPOSTS_AVAILABLE() \
24 __builtin_available(macos 10.14, iOS 12, tvOS 12, watchOS 5, *)
25namespace {
26os_log_t *LogCreator() {
27 os_log_t *X = new os_log_t;
28 *X = os_log_create("org.llvm.signposts", "toolchain");
29 return X;
30}
31struct LogDeleter {
32 void operator()(os_log_t *X) const {
33 os_release(*X);
34 delete X;
35 }
36};
37} // end anonymous namespace
38
39namespace llvm {
40class SignpostEmitterImpl {
41 using LogPtrTy = std::unique_ptr<os_log_t, LogDeleter>;
42 using LogTy = LogPtrTy::element_type;
43
44 LogPtrTy SignpostLog;
45 DenseMap<const void *, os_signpost_id_t> Signposts;
46 sys::SmartMutex<true> Mutex;
47
48 LogTy &getLogger() const { return *SignpostLog; }
49 os_signpost_id_t getSignpostForObject(const void *O) {
50 sys::SmartScopedLock<true> Lock(Mutex);
51 const auto &I = Signposts.find(O);
52 if (I != Signposts.end())
53 return I->second;
54 os_signpost_id_t ID = {};
55 if (SIGNPOSTS_AVAILABLE()) {
56 ID = os_signpost_id_make_with_pointer(getLogger(), O);
57 }
58 const auto &Inserted = Signposts.insert(std::make_pair(O, ID));
59 return Inserted.first->second;
60 }
61
62public:
63 SignpostEmitterImpl() : SignpostLog(LogCreator()) {}
64
65 bool isEnabled() const {
66 if (SIGNPOSTS_AVAILABLE())
67 return os_signpost_enabled(*SignpostLog);
68 return false;
69 }
70
71 void startInterval(const void *O, llvm::StringRef Name) {
72 if (isEnabled()) {
73 if (SIGNPOSTS_AVAILABLE()) {
74 // Both strings used here are required to be constant literal strings.
75 os_signpost_interval_begin(getLogger(), getSignpostForObject(O),
76 "LLVM Timers", "%s", Name.data());
77 }
78 }
79 }
80
81 void endInterval(const void *O, llvm::StringRef Name) {
82 if (isEnabled()) {
83 if (SIGNPOSTS_AVAILABLE()) {
84 // Both strings used here are required to be constant literal strings.
85 os_signpost_interval_end(getLogger(), getSignpostForObject(O),
86 "LLVM Timers", "");
87 }
88 }
89 }
90};
91} // end namespace llvm
92#else
93/// Definition necessary for use of std::unique_ptr in SignpostEmitter::Impl.
94class llvm::SignpostEmitterImpl {};
95#endif // if LLVM_SUPPORT_XCODE_SIGNPOSTS
96
97#if LLVM_SUPPORT_XCODE_SIGNPOSTS
98#define HAVE_ANY_SIGNPOST_IMPL 1
99#else
100#define HAVE_ANY_SIGNPOST_IMPL 0
101#endif
102
103SignpostEmitter::SignpostEmitter() {
104#if HAVE_ANY_SIGNPOST_IMPL
105 Impl = std::make_unique<SignpostEmitterImpl>();
106#endif // if !HAVE_ANY_SIGNPOST_IMPL
107}
108
109SignpostEmitter::~SignpostEmitter() = default;
110
111bool SignpostEmitter::isEnabled() const {
112#if HAVE_ANY_SIGNPOST_IMPL
113 return Impl->isEnabled();
114#else
115 return false;
116#endif // if !HAVE_ANY_SIGNPOST_IMPL
117}
118
119void SignpostEmitter::startInterval(const void *O, StringRef Name) {
120#if HAVE_ANY_SIGNPOST_IMPL
121 if (Impl == nullptr)
122 return;
123 return Impl->startInterval(O, Name);
124#endif // if !HAVE_ANY_SIGNPOST_IMPL
125}
126
127void SignpostEmitter::endInterval(const void *O, StringRef Name) {
128#if HAVE_ANY_SIGNPOST_IMPL
129 if (Impl == nullptr)
130 return;
131 Impl->endInterval(O, Name);
132#endif // if !HAVE_ANY_SIGNPOST_IMPL
133}
134

source code of llvm/lib/Support/Signposts.cpp