1 //=-- SampleProf.cpp - Sample profiling format support --------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains common definitions used in the reading and writing of
11 // sample profile data.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/IR/DebugInfoMetadata.h"
16 #include "llvm/ProfileData/SampleProf.h"
17 #include "llvm/Support/Compiler.h"
18 #include "llvm/Support/Debug.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/ManagedStatic.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include <string>
23 #include <system_error>
24 
25 using namespace llvm;
26 using namespace sampleprof;
27 
28 namespace {
29 
30 // FIXME: This class is only here to support the transition to llvm::Error. It
31 // will be removed once this transition is complete. Clients should prefer to
32 // deal with the Error value directly, rather than converting to error_code.
33 class SampleProfErrorCategoryType : public std::error_category {
34   const char *name() const noexcept override { return "llvm.sampleprof"; }
35 
36   std::string message(int IE) const override {
37     sampleprof_error E = static_cast<sampleprof_error>(IE);
38     switch (E) {
39     case sampleprof_error::success:
40       return "Success";
41     case sampleprof_error::bad_magic:
42       return "Invalid sample profile data (bad magic)";
43     case sampleprof_error::unsupported_version:
44       return "Unsupported sample profile format version";
45     case sampleprof_error::too_large:
46       return "Too much profile data";
47     case sampleprof_error::truncated:
48       return "Truncated profile data";
49     case sampleprof_error::malformed:
50       return "Malformed sample profile data";
51     case sampleprof_error::unrecognized_format:
52       return "Unrecognized sample profile encoding format";
53     case sampleprof_error::unsupported_writing_format:
54       return "Profile encoding format unsupported for writing operations";
55     case sampleprof_error::truncated_name_table:
56       return "Truncated function name table";
57     case sampleprof_error::not_implemented:
58       return "Unimplemented feature";
59     case sampleprof_error::counter_overflow:
60       return "Counter overflow";
61     }
62     llvm_unreachable("A value of sampleprof_error has no message.");
63   }
64 };
65 
66 } // end anonymous namespace
67 
68 static ManagedStatic<SampleProfErrorCategoryType> ErrorCategory;
69 
70 const std::error_category &llvm::sampleprof_category() {
71   return *ErrorCategory;
72 }
73 
74 void LineLocation::print(raw_ostream &OS) const {
75   OS << LineOffset;
76   if (Discriminator > 0)
77     OS << "." << Discriminator;
78 }
79 
80 raw_ostream &llvm::sampleprof::operator<<(raw_ostream &OS,
81                                           const LineLocation &Loc) {
82   Loc.print(OS);
83   return OS;
84 }
85 
86 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
87 LLVM_DUMP_METHOD void LineLocation::dump() const { print(dbgs()); }
88 #endif
89 
90 /// \brief Print the sample record to the stream \p OS indented by \p Indent.
91 void SampleRecord::print(raw_ostream &OS, unsigned Indent) const {
92   OS << NumSamples;
93   if (hasCalls()) {
94     OS << ", calls:";
95     for (const auto &I : getCallTargets())
96       OS << " " << I.first() << ":" << I.second;
97   }
98   OS << "\n";
99 }
100 
101 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
102 LLVM_DUMP_METHOD void SampleRecord::dump() const { print(dbgs(), 0); }
103 #endif
104 
105 raw_ostream &llvm::sampleprof::operator<<(raw_ostream &OS,
106                                           const SampleRecord &Sample) {
107   Sample.print(OS, 0);
108   return OS;
109 }
110 
111 /// \brief Print the samples collected for a function on stream \p OS.
112 void FunctionSamples::print(raw_ostream &OS, unsigned Indent) const {
113   OS << TotalSamples << ", " << TotalHeadSamples << ", " << BodySamples.size()
114      << " sampled lines\n";
115 
116   OS.indent(Indent);
117   if (!BodySamples.empty()) {
118     OS << "Samples collected in the function's body {\n";
119     SampleSorter<LineLocation, SampleRecord> SortedBodySamples(BodySamples);
120     for (const auto &SI : SortedBodySamples.get()) {
121       OS.indent(Indent + 2);
122       OS << SI->first << ": " << SI->second;
123     }
124     OS.indent(Indent);
125     OS << "}\n";
126   } else {
127     OS << "No samples collected in the function's body\n";
128   }
129 
130   OS.indent(Indent);
131   if (!CallsiteSamples.empty()) {
132     OS << "Samples collected in inlined callsites {\n";
133     SampleSorter<LineLocation, FunctionSamplesMap> SortedCallsiteSamples(
134         CallsiteSamples);
135     for (const auto &CS : SortedCallsiteSamples.get()) {
136       for (const auto &FS : CS->second) {
137         OS.indent(Indent + 2);
138         OS << CS->first << ": inlined callee: " << FS.second.getName() << ": ";
139         FS.second.print(OS, Indent + 4);
140       }
141     }
142     OS << "}\n";
143   } else {
144     OS << "No inlined callsites in this function\n";
145   }
146 }
147 
148 raw_ostream &llvm::sampleprof::operator<<(raw_ostream &OS,
149                                           const FunctionSamples &FS) {
150   FS.print(OS);
151   return OS;
152 }
153 
154 unsigned FunctionSamples::getOffset(const DILocation *DIL) {
155   return (DIL->getLine() - DIL->getScope()->getSubprogram()->getLine()) &
156       0xffff;
157 }
158 
159 const FunctionSamples *
160 FunctionSamples::findFunctionSamples(const DILocation *DIL) const {
161   assert(DIL);
162   SmallVector<std::pair<LineLocation, StringRef>, 10> S;
163 
164   const DILocation *PrevDIL = DIL;
165   for (DIL = DIL->getInlinedAt(); DIL; DIL = DIL->getInlinedAt()) {
166     S.push_back(std::make_pair(
167         LineLocation(getOffset(DIL), DIL->getBaseDiscriminator()),
168         PrevDIL->getScope()->getSubprogram()->getLinkageName()));
169     PrevDIL = DIL;
170   }
171   if (S.size() == 0)
172     return this;
173   const FunctionSamples *FS = this;
174   for (int i = S.size() - 1; i >= 0 && FS != nullptr; i--) {
175     FS = FS->findFunctionSamplesAt(S[i].first, S[i].second);
176   }
177   return FS;
178 }
179 
180 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
181 LLVM_DUMP_METHOD void FunctionSamples::dump() const { print(dbgs(), 0); }
182 #endif
183