xref: /freebsd/contrib/llvm-project/llvm/lib/Support/Signposts.cpp (revision 5956d97f4b3204318ceb6aa9c77bd0bc6ea87a41)
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 
11 #include "llvm/Config/config.h"
12 #if LLVM_SUPPORT_XCODE_SIGNPOSTS
13 #include "llvm/ADT/DenseMap.h"
14 #include "llvm/Support/Mutex.h"
15 #include <Availability.h>
16 #include <os/signpost.h>
17 #endif // if LLVM_SUPPORT_XCODE_SIGNPOSTS
18 
19 using namespace llvm;
20 
21 #if LLVM_SUPPORT_XCODE_SIGNPOSTS
22 #define SIGNPOSTS_AVAILABLE()                                                  \
23   __builtin_available(macos 10.14, iOS 12, tvOS 12, watchOS 5, *)
24 namespace {
25 os_log_t *LogCreator() {
26   os_log_t *X = new os_log_t;
27   *X = os_log_create("org.llvm.signposts", OS_LOG_CATEGORY_POINTS_OF_INTEREST);
28   return X;
29 }
30 struct LogDeleter {
31   void operator()(os_log_t *X) const {
32     os_release(*X);
33     delete X;
34   }
35 };
36 } // end anonymous namespace
37 
38 namespace llvm {
39 class SignpostEmitterImpl {
40   using LogPtrTy = std::unique_ptr<os_log_t, LogDeleter>;
41   using LogTy = LogPtrTy::element_type;
42 
43   LogPtrTy SignpostLog;
44   DenseMap<const void *, os_signpost_id_t> Signposts;
45   sys::SmartMutex<true> Mutex;
46 
47   LogTy &getLogger() const { return *SignpostLog; }
48   os_signpost_id_t getSignpostForObject(const void *O) {
49     sys::SmartScopedLock<true> Lock(Mutex);
50     const auto &I = Signposts.find(O);
51     if (I != Signposts.end())
52       return I->second;
53     os_signpost_id_t ID = {};
54     if (SIGNPOSTS_AVAILABLE()) {
55       ID = os_signpost_id_make_with_pointer(getLogger(), O);
56     }
57     const auto &Inserted = Signposts.insert(std::make_pair(O, ID));
58     return Inserted.first->second;
59   }
60 
61 public:
62   SignpostEmitterImpl() : SignpostLog(LogCreator()) {}
63 
64   bool isEnabled() const {
65     if (SIGNPOSTS_AVAILABLE())
66       return os_signpost_enabled(*SignpostLog);
67     return false;
68   }
69 
70   void startInterval(const void *O, llvm::StringRef Name) {
71     if (isEnabled()) {
72       if (SIGNPOSTS_AVAILABLE()) {
73         // Both strings used here are required to be constant literal strings.
74         os_signpost_interval_begin(getLogger(), getSignpostForObject(O),
75                                    "LLVM Timers", "%s", Name.data());
76       }
77     }
78   }
79 
80   void endInterval(const void *O, llvm::StringRef Name) {
81     if (isEnabled()) {
82       if (SIGNPOSTS_AVAILABLE()) {
83         // Both strings used here are required to be constant literal strings.
84         os_signpost_interval_end(getLogger(), getSignpostForObject(O),
85                                  "LLVM Timers", "");
86       }
87     }
88   }
89 };
90 } // end namespace llvm
91 #else
92 /// Definition necessary for use of std::unique_ptr in SignpostEmitter::Impl.
93 class llvm::SignpostEmitterImpl {};
94 #endif // if LLVM_SUPPORT_XCODE_SIGNPOSTS
95 
96 #if LLVM_SUPPORT_XCODE_SIGNPOSTS
97 #define HAVE_ANY_SIGNPOST_IMPL 1
98 #else
99 #define HAVE_ANY_SIGNPOST_IMPL 0
100 #endif
101 
102 SignpostEmitter::SignpostEmitter() {
103 #if HAVE_ANY_SIGNPOST_IMPL
104   Impl = std::make_unique<SignpostEmitterImpl>();
105 #endif // if !HAVE_ANY_SIGNPOST_IMPL
106 }
107 
108 SignpostEmitter::~SignpostEmitter() = default;
109 
110 bool SignpostEmitter::isEnabled() const {
111 #if HAVE_ANY_SIGNPOST_IMPL
112   return Impl->isEnabled();
113 #else
114   return false;
115 #endif // if !HAVE_ANY_SIGNPOST_IMPL
116 }
117 
118 void SignpostEmitter::startInterval(const void *O, StringRef Name) {
119 #if HAVE_ANY_SIGNPOST_IMPL
120   if (Impl == nullptr)
121     return;
122   return Impl->startInterval(O, Name);
123 #endif // if !HAVE_ANY_SIGNPOST_IMPL
124 }
125 
126 void SignpostEmitter::endInterval(const void *O, StringRef Name) {
127 #if HAVE_ANY_SIGNPOST_IMPL
128   if (Impl == nullptr)
129     return;
130   Impl->endInterval(O, Name);
131 #endif // if !HAVE_ANY_SIGNPOST_IMPL
132 }
133