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
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
//===- bolt/Profile/YAMLProfileWriter.cpp - YAML profile serializer -------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "bolt/Profile/YAMLProfileWriter.h"
#include "bolt/Core/BinaryBasicBlock.h"
#include "bolt/Core/BinaryFunction.h"
#include "bolt/Profile/ProfileReaderBase.h"
#include "bolt/Profile/ProfileYAMLMapping.h"
#include "bolt/Rewrite/RewriteInstance.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/raw_ostream.h"
#undef DEBUG_TYPE
#define DEBUG_TYPE "bolt-prof"
namespace llvm {
namespace bolt {
namespace {
void convert(const BinaryFunction &BF,
yaml::bolt::BinaryFunctionProfile &YamlBF) {
const BinaryContext &BC = BF.getBinaryContext();
const uint16_t LBRProfile = BF.getProfileFlags() & BinaryFunction::PF_LBR;
// Prepare function and block hashes
BF.computeHash(/*UseDFS=*/true);
BF.computeBlockHashes();
YamlBF.Name = BF.getPrintName();
YamlBF.Id = BF.getFunctionNumber();
YamlBF.Hash = BF.getHash();
YamlBF.NumBasicBlocks = BF.size();
YamlBF.ExecCount = BF.getKnownExecutionCount();
for (const BinaryBasicBlock *BB : BF.dfs()) {
yaml::bolt::BinaryBasicBlockProfile YamlBB;
YamlBB.Index = BB->getLayoutIndex();
YamlBB.NumInstructions = BB->getNumNonPseudos();
YamlBB.Hash = BB->getHash();
if (!LBRProfile) {
YamlBB.EventCount = BB->getKnownExecutionCount();
if (YamlBB.EventCount)
YamlBF.Blocks.emplace_back(YamlBB);
continue;
}
YamlBB.ExecCount = BB->getKnownExecutionCount();
for (const MCInst &Instr : *BB) {
if (!BC.MIB->isCall(Instr) && !BC.MIB->isIndirectBranch(Instr))
continue;
yaml::bolt::CallSiteInfo CSI;
std::optional<uint32_t> Offset = BC.MIB->getOffset(Instr);
if (!Offset || *Offset < BB->getInputOffset())
continue;
CSI.Offset = *Offset - BB->getInputOffset();
if (BC.MIB->isIndirectCall(Instr) || BC.MIB->isIndirectBranch(Instr)) {
const auto ICSP = BC.MIB->tryGetAnnotationAs<IndirectCallSiteProfile>(
Instr, "CallProfile");
if (!ICSP)
continue;
for (const IndirectCallProfile &CSP : ICSP.get()) {
CSI.DestId = 0; // designated for unknown functions
CSI.EntryDiscriminator = 0;
if (CSP.Symbol) {
const BinaryFunction *Callee = BC.getFunctionForSymbol(CSP.Symbol);
if (Callee)
CSI.DestId = Callee->getFunctionNumber();
}
CSI.Count = CSP.Count;
CSI.Mispreds = CSP.Mispreds;
YamlBB.CallSites.push_back(CSI);
}
} else { // direct call or a tail call
uint64_t EntryID = 0;
const MCSymbol *CalleeSymbol = BC.MIB->getTargetSymbol(Instr);
const BinaryFunction *const Callee =
BC.getFunctionForSymbol(CalleeSymbol, &EntryID);
if (Callee) {
CSI.DestId = Callee->getFunctionNumber();
CSI.EntryDiscriminator = EntryID;
}
if (BC.MIB->getConditionalTailCall(Instr)) {
auto CTCCount =
BC.MIB->tryGetAnnotationAs<uint64_t>(Instr, "CTCTakenCount");
if (CTCCount) {
CSI.Count = *CTCCount;
auto CTCMispreds =
BC.MIB->tryGetAnnotationAs<uint64_t>(Instr, "CTCMispredCount");
if (CTCMispreds)
CSI.Mispreds = *CTCMispreds;
}
} else {
auto Count = BC.MIB->tryGetAnnotationAs<uint64_t>(Instr, "Count");
if (Count)
CSI.Count = *Count;
}
if (CSI.Count)
YamlBB.CallSites.emplace_back(CSI);
}
}
llvm::sort(YamlBB.CallSites);
// Skip printing if there's no profile data for non-entry basic block.
// Include landing pads with non-zero execution count.
if (YamlBB.CallSites.empty() && !BB->isEntryPoint() &&
!(BB->isLandingPad() && BB->getKnownExecutionCount() != 0)) {
// Include blocks having successors or predecessors with positive counts.
uint64_t SuccessorExecCount = 0;
for (const BinaryBasicBlock::BinaryBranchInfo &BranchInfo :
BB->branch_info())
SuccessorExecCount += BranchInfo.Count;
uint64_t PredecessorExecCount = 0;
for (auto Pred : BB->predecessors())
PredecessorExecCount += Pred->getBranchInfo(*BB).Count;
if (!SuccessorExecCount && !PredecessorExecCount)
continue;
}
auto BranchInfo = BB->branch_info_begin();
for (const BinaryBasicBlock *Successor : BB->successors()) {
yaml::bolt::SuccessorInfo YamlSI;
YamlSI.Index = Successor->getLayoutIndex();
YamlSI.Count = BranchInfo->Count;
YamlSI.Mispreds = BranchInfo->MispredictedCount;
YamlBB.Successors.emplace_back(YamlSI);
++BranchInfo;
}
YamlBF.Blocks.emplace_back(YamlBB);
}
}
} // end anonymous namespace
std::error_code YAMLProfileWriter::writeProfile(const RewriteInstance &RI) {
const BinaryContext &BC = RI.getBinaryContext();
const auto &Functions = BC.getBinaryFunctions();
std::error_code EC;
OS = std::make_unique<raw_fd_ostream>(Filename, EC, sys::fs::OF_None);
if (EC) {
errs() << "BOLT-WARNING: " << EC.message() << " : unable to open "
<< Filename << " for output.\n";
return EC;
}
yaml::bolt::BinaryProfile BP;
// Fill out the header info.
BP.Header.Version = 1;
BP.Header.FileName = std::string(BC.getFilename());
std::optional<StringRef> BuildID = BC.getFileBuildID();
BP.Header.Id = BuildID ? std::string(*BuildID) : "<unknown>";
BP.Header.Origin = std::string(RI.getProfileReader()->getReaderName());
StringSet<> EventNames = RI.getProfileReader()->getEventNames();
if (!EventNames.empty()) {
std::string Sep;
for (const StringMapEntry<std::nullopt_t> &EventEntry : EventNames) {
BP.Header.EventNames += Sep + EventEntry.first().str();
Sep = ",";
}
}
// Make sure the profile is consistent across all functions.
uint16_t ProfileFlags = BinaryFunction::PF_NONE;
for (const auto &BFI : Functions) {
const BinaryFunction &BF = BFI.second;
if (BF.hasProfile() && !BF.empty()) {
assert(BF.getProfileFlags() != BinaryFunction::PF_NONE);
if (ProfileFlags == BinaryFunction::PF_NONE)
ProfileFlags = BF.getProfileFlags();
assert(BF.getProfileFlags() == ProfileFlags &&
"expected consistent profile flags across all functions");
}
}
BP.Header.Flags = ProfileFlags;
// Add all function objects.
for (const auto &BFI : Functions) {
const BinaryFunction &BF = BFI.second;
if (BF.hasProfile()) {
if (!BF.hasValidProfile() && !RI.getProfileReader()->isTrustedSource())
continue;
yaml::bolt::BinaryFunctionProfile YamlBF;
convert(BF, YamlBF);
BP.Functions.emplace_back(YamlBF);
}
}
// Write the profile.
yaml::Output Out(*OS, nullptr, 0);
Out << BP;
return std::error_code();
}
} // namespace bolt
} // namespace llvm
|
