1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
//===- SampleProfReader.h - Read LLVM sample profile data -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains definitions needed for reading sample profiles.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_PROFILEDATA_SAMPLEPROFREADER_H
#define LLVM_PROFILEDATA_SAMPLEPROFREADER_H
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/ProfileData/SampleProf.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ErrorOr.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
namespace llvm {
namespace sampleprof {
/// \brief Sample-based profile reader.
///
/// Each profile contains sample counts for all the functions
/// executed. Inside each function, statements are annotated with the
/// collected samples on all the instructions associated with that
/// statement.
///
/// For this to produce meaningful data, the program needs to be
/// compiled with some debug information (at minimum, line numbers:
/// -gline-tables-only). Otherwise, it will be impossible to match IR
/// instructions to the line numbers collected by the profiler.
///
/// From the profile file, we are interested in collecting the
/// following information:
///
/// * A list of functions included in the profile (mangled names).
///
/// * For each function F:
/// 1. The total number of samples collected in F.
///
/// 2. The samples collected at each line in F. To provide some
/// protection against source code shuffling, line numbers should
/// be relative to the start of the function.
///
/// The reader supports two file formats: text and binary. The text format
/// is useful for debugging and testing, while the binary format is more
/// compact. They can both be used interchangeably.
class SampleProfileReader {
public:
SampleProfileReader(std::unique_ptr<MemoryBuffer> B, LLVMContext &C)
: Profiles(0), Ctx(C), Buffer(std::move(B)) {}
virtual ~SampleProfileReader() {}
/// \brief Read and validate the file header.
virtual std::error_code readHeader() = 0;
/// \brief Read sample profiles from the associated file.
virtual std::error_code read() = 0;
/// \brief Print the profile for \p FName on stream \p OS.
void dumpFunctionProfile(StringRef FName, raw_ostream &OS = dbgs());
/// \brief Print all the profiles on stream \p OS.
void dump(raw_ostream &OS = dbgs());
/// \brief Return the samples collected for function \p F.
FunctionSamples *getSamplesFor(const Function &F) {
return &Profiles[F.getName()];
}
/// \brief Return all the profiles.
StringMap<FunctionSamples> &getProfiles() { return Profiles; }
/// \brief Report a parse error message.
void reportParseError(int64_t LineNumber, Twine Msg) const {
Ctx.diagnose(DiagnosticInfoSampleProfile(Buffer->getBufferIdentifier(),
LineNumber, Msg));
}
/// \brief Create a sample profile reader appropriate to the file format.
static ErrorOr<std::unique_ptr<SampleProfileReader>>
create(StringRef Filename, LLVMContext &C);
protected:
/// \brief Map every function to its associated profile.
///
/// The profile of every function executed at runtime is collected
/// in the structure FunctionSamples. This maps function objects
/// to their corresponding profiles.
StringMap<FunctionSamples> Profiles;
/// \brief LLVM context used to emit diagnostics.
LLVMContext &Ctx;
/// \brief Memory buffer holding the profile file.
std::unique_ptr<MemoryBuffer> Buffer;
};
class SampleProfileReaderText : public SampleProfileReader {
public:
SampleProfileReaderText(std::unique_ptr<MemoryBuffer> B, LLVMContext &C)
: SampleProfileReader(std::move(B), C) {}
/// \brief Read and validate the file header.
std::error_code readHeader() override { return sampleprof_error::success; }
/// \brief Read sample profiles from the associated file.
std::error_code read() override;
};
class SampleProfileReaderBinary : public SampleProfileReader {
public:
SampleProfileReaderBinary(std::unique_ptr<MemoryBuffer> B, LLVMContext &C)
: SampleProfileReader(std::move(B), C), Data(nullptr), End(nullptr) {}
/// \brief Read and validate the file header.
std::error_code readHeader() override;
/// \brief Read sample profiles from the associated file.
std::error_code read() override;
/// \brief Return true if \p Buffer is in the format supported by this class.
static bool hasFormat(const MemoryBuffer &Buffer);
protected:
/// \brief Read a numeric value of type T from the profile.
///
/// If an error occurs during decoding, a diagnostic message is emitted and
/// EC is set.
///
/// \returns the read value.
template <typename T> ErrorOr<T> readNumber();
/// \brief Read a string from the profile.
///
/// If an error occurs during decoding, a diagnostic message is emitted and
/// EC is set.
///
/// \returns the read value.
ErrorOr<StringRef> readString();
/// \brief Return true if we've reached the end of file.
bool at_eof() const { return Data >= End; }
/// \brief Points to the current location in the buffer.
const uint8_t *Data;
/// \brief Points to the end of the buffer.
const uint8_t *End;
};
} // End namespace sampleprof
} // End namespace llvm
#endif // LLVM_PROFILEDATA_SAMPLEPROFREADER_H
|
