1//===- InstrProfWriter.h - Instrumented profiling writer --------*- C++ -*-===//
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// This file contains support for writing profiling data for instrumentation
10// based PGO and coverage.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_PROFILEDATA_INSTRPROFWRITER_H
15#define LLVM_PROFILEDATA_INSTRPROFWRITER_H
16
17#include "llvm/ADT/DenseMap.h"
18#include "llvm/ADT/MapVector.h"
19#include "llvm/ADT/StringMap.h"
20#include "llvm/IR/GlobalValue.h"
21#include "llvm/Object/BuildID.h"
22#include "llvm/ProfileData/InstrProf.h"
23#include "llvm/ProfileData/MemProf.h"
24#include "llvm/Support/Error.h"
25#include <cstdint>
26#include <memory>
27#include <random>
28
29namespace llvm {
30
31/// Writer for instrumentation based profile data.
32class InstrProfRecordWriterTrait;
33class ProfOStream;
34class MemoryBuffer;
35class raw_fd_ostream;
36
37class InstrProfWriter {
38public:
39 using ProfilingData = SmallDenseMap<uint64_t, InstrProfRecord>;
40
41private:
42 bool Sparse;
43 StringMap<ProfilingData> FunctionData;
44 /// The maximum length of a single temporal profile trace.
45 uint64_t MaxTemporalProfTraceLength;
46 /// The maximum number of stored temporal profile traces.
47 uint64_t TemporalProfTraceReservoirSize;
48 /// The total number of temporal profile traces seen.
49 uint64_t TemporalProfTraceStreamSize = 0;
50 /// The list of temporal profile traces.
51 SmallVector<TemporalProfTraceTy> TemporalProfTraces;
52 std::mt19937 RNG;
53
54 // A map to hold memprof data per function. The lower 64 bits obtained from
55 // the md5 hash of the function name is used to index into the map.
56 llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord>
57 MemProfRecordData;
58 // A map to hold frame id to frame mappings. The mappings are used to
59 // convert IndexedMemProfRecord to MemProfRecords with frame information
60 // inline.
61 llvm::MapVector<memprof::FrameId, memprof::Frame> MemProfFrameData;
62
63 // List of binary ids.
64 std::vector<llvm::object::BuildID> BinaryIds;
65
66 // An enum describing the attributes of the profile.
67 InstrProfKind ProfileKind = InstrProfKind::Unknown;
68 // Use raw pointer here for the incomplete type object.
69 InstrProfRecordWriterTrait *InfoObj;
70
71public:
72 InstrProfWriter(bool Sparse = false,
73 uint64_t TemporalProfTraceReservoirSize = 0,
74 uint64_t MaxTemporalProfTraceLength = 0);
75 ~InstrProfWriter();
76
77 StringMap<ProfilingData> &getProfileData() { return FunctionData; }
78
79 /// Add function counts for the given function. If there are already counts
80 /// for this function and the hash and number of counts match, each counter is
81 /// summed. Optionally scale counts by \p Weight.
82 void addRecord(NamedInstrProfRecord &&I, uint64_t Weight,
83 function_ref<void(Error)> Warn);
84 void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) {
85 addRecord(I: std::move(I), Weight: 1, Warn);
86 }
87
88 /// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the
89 /// total number of temporal profiling traces the source has seen.
90 void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces,
91 uint64_t SrcStreamSize);
92
93 /// Add a memprof record for a function identified by its \p Id.
94 void addMemProfRecord(const GlobalValue::GUID Id,
95 const memprof::IndexedMemProfRecord &Record);
96
97 /// Add a memprof frame identified by the hash of the contents of the frame in
98 /// \p FrameId.
99 bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F,
100 function_ref<void(Error)> Warn);
101
102 // Add a binary id to the binary ids list.
103 void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs);
104
105 /// Merge existing function counts from the given writer.
106 void mergeRecordsFromWriter(InstrProfWriter &&IPW,
107 function_ref<void(Error)> Warn);
108
109 /// Write the profile to \c OS
110 Error write(raw_fd_ostream &OS);
111
112 /// Write the profile to a string output stream \c OS
113 Error write(raw_string_ostream &OS);
114
115 /// Write the profile in text format to \c OS
116 Error writeText(raw_fd_ostream &OS);
117
118 /// Write temporal profile trace data to the header in text format to \c OS
119 void writeTextTemporalProfTraceData(raw_fd_ostream &OS,
120 InstrProfSymtab &Symtab);
121
122 Error validateRecord(const InstrProfRecord &Func);
123
124 /// Write \c Record in text format to \c OS
125 static void writeRecordInText(StringRef Name, uint64_t Hash,
126 const InstrProfRecord &Counters,
127 InstrProfSymtab &Symtab, raw_fd_ostream &OS);
128
129 /// Write the profile, returning the raw data. For testing.
130 std::unique_ptr<MemoryBuffer> writeBuffer();
131
132 /// Update the attributes of the current profile from the attributes
133 /// specified. An error is returned if IR and FE profiles are mixed.
134 Error mergeProfileKind(const InstrProfKind Other) {
135 // If the kind is unset, this is the first profile we are merging so just
136 // set it to the given type.
137 if (ProfileKind == InstrProfKind::Unknown) {
138 ProfileKind = Other;
139 return Error::success();
140 }
141
142 // Returns true if merging is should fail assuming A and B are incompatible.
143 auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) {
144 return (static_cast<bool>(ProfileKind & A) &&
145 static_cast<bool>(Other & B)) ||
146 (static_cast<bool>(ProfileKind & B) &&
147 static_cast<bool>(Other & A));
148 };
149
150 // Check if the profiles are in-compatible. Clang frontend profiles can't be
151 // merged with other profile types.
152 if (static_cast<bool>(
153 (ProfileKind & InstrProfKind::FrontendInstrumentation) ^
154 (Other & InstrProfKind::FrontendInstrumentation))) {
155 return make_error<InstrProfError>(Args: instrprof_error::unsupported_version);
156 }
157 if (testIncompatible(InstrProfKind::FunctionEntryOnly,
158 InstrProfKind::FunctionEntryInstrumentation)) {
159 return make_error<InstrProfError>(
160 Args: instrprof_error::unsupported_version,
161 Args: "cannot merge FunctionEntryOnly profiles and BB profiles together");
162 }
163
164 // Now we update the profile type with the bits that are set.
165 ProfileKind |= Other;
166 return Error::success();
167 }
168
169 InstrProfKind getProfileKind() const { return ProfileKind; }
170
171 // Internal interface for testing purpose only.
172 void setValueProfDataEndianness(llvm::endianness Endianness);
173 void setOutputSparse(bool Sparse);
174 // Compute the overlap b/w this object and Other. Program level result is
175 // stored in Overlap and function level result is stored in FuncLevelOverlap.
176 void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap,
177 OverlapStats &FuncLevelOverlap,
178 const OverlapFuncFilters &FuncFilter);
179
180private:
181 void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I,
182 uint64_t Weight, function_ref<void(Error)> Warn);
183 bool shouldEncodeData(const ProfilingData &PD);
184 /// Add \p Trace using reservoir sampling.
185 void addTemporalProfileTrace(TemporalProfTraceTy Trace);
186
187 Error writeImpl(ProfOStream &OS);
188};
189
190} // end namespace llvm
191
192#endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H
193

source code of llvm/include/llvm/ProfileData/InstrProfWriter.h