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
|
//===- bolt/Passes/StokeInfo.cpp ------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file implements the StokeInfo class.
//
//===----------------------------------------------------------------------===//
#include "bolt/Passes/StokeInfo.h"
#include "bolt/Passes/BinaryFunctionCallGraph.h"
#include "bolt/Passes/DataflowInfoManager.h"
#include "llvm/Support/CommandLine.h"
#define DEBUG_TYPE "stoke"
using namespace llvm;
using namespace bolt;
namespace opts {
cl::OptionCategory StokeOptCategory("STOKE pass options");
static cl::opt<std::string>
StokeOutputDataFilename("stoke-out",
cl::desc("output data (.csv) for Stoke's use"),
cl::Optional,
cl::cat(StokeOptCategory));
}
namespace llvm {
namespace bolt {
void getRegNameFromBitVec(const BinaryContext &BC, const BitVector &RegV,
std::set<std::string> *NameVec = nullptr) {
for (int RegIdx : RegV.set_bits()) {
LLVM_DEBUG(dbgs() << BC.MRI->getName(RegIdx) << " ");
if (NameVec)
NameVec->insert(std::string(BC.MRI->getName(RegIdx)));
}
LLVM_DEBUG(dbgs() << "\n");
}
void StokeInfo::checkInstr(const BinaryFunction &BF, StokeFuncInfo &FuncInfo) {
MCPlusBuilder *MIB = BF.getBinaryContext().MIB.get();
BitVector RegV(NumRegs, false);
for (const BinaryBasicBlock *BB : BF.getLayout().blocks()) {
if (BB->empty())
continue;
// Skip function with exception handling.
if (BB->throw_size() || BB->lp_size()) {
FuncInfo.Omitted = true;
return;
}
for (const MCInst &It : *BB) {
if (MIB->isPseudo(It))
continue;
// skip function with exception handling yet
if (MIB->isInvoke(It)) {
FuncInfo.Omitted = true;
return;
}
// check if this function contains call instruction
if (MIB->isCall(It)) {
FuncInfo.HasCall = true;
const MCSymbol *TargetSymbol = MIB->getTargetSymbol(It);
// if it is an indirect call, skip
if (TargetSymbol == nullptr) {
FuncInfo.Omitted = true;
return;
}
}
// check if this function modify stack or heap
// TODO: more accurate analysis
bool IsPush = MIB->isPush(It);
bool IsRipAddr = MIB->hasPCRelOperand(It);
if (IsPush)
FuncInfo.StackOut = true;
if (MIB->mayStore(It) && !IsPush && !IsRipAddr)
FuncInfo.HeapOut = true;
if (IsRipAddr)
FuncInfo.HasRipAddr = true;
} // end of for (auto &It : ...)
} // end of for (auto *BB : ...)
}
bool StokeInfo::checkFunction(BinaryFunction &BF, DataflowInfoManager &DInfo,
RegAnalysis &RA, StokeFuncInfo &FuncInfo) {
std::string Name = BF.getSymbol()->getName().str();
if (!BF.isSimple() || BF.isMultiEntry() || BF.empty())
return false;
outs() << " STOKE-INFO: analyzing function " << Name << "\n";
FuncInfo.FuncName = Name;
FuncInfo.Offset = BF.getFileOffset();
FuncInfo.Size = BF.getMaxSize();
FuncInfo.NumInstrs = BF.getNumNonPseudos();
FuncInfo.NumBlocks = BF.size();
// early stop for large functions
if (FuncInfo.NumInstrs > 500)
return false;
FuncInfo.IsLoopFree = BF.isLoopFree();
if (!FuncInfo.IsLoopFree) {
const BinaryLoopInfo &BLI = BF.getLoopInfo();
FuncInfo.NumLoops = BLI.OuterLoops;
FuncInfo.MaxLoopDepth = BLI.MaximumDepth;
}
FuncInfo.HotSize = BF.estimateHotSize();
FuncInfo.TotalSize = BF.estimateSize();
FuncInfo.Score = BF.getFunctionScore();
checkInstr(BF, FuncInfo);
// register analysis
BinaryBasicBlock &EntryBB = BF.front();
assert(EntryBB.isEntryPoint() && "Weird, this should be the entry block!");
MCInst *FirstNonPseudo = EntryBB.getFirstNonPseudoInstr();
if (!FirstNonPseudo)
return false;
LLVM_DEBUG(dbgs() << "\t [DefIn]\n\t ");
BitVector LiveInBV =
*(DInfo.getLivenessAnalysis().getStateAt(FirstNonPseudo));
LiveInBV &= DefaultDefInMask;
getRegNameFromBitVec(BF.getBinaryContext(), LiveInBV, &FuncInfo.DefIn);
LLVM_DEBUG(dbgs() << "\t [LiveOut]\n\t ");
BitVector LiveOutBV = RA.getFunctionClobberList(&BF);
LiveOutBV &= DefaultLiveOutMask;
getRegNameFromBitVec(BF.getBinaryContext(), LiveOutBV, &FuncInfo.LiveOut);
outs() << " STOKE-INFO: end function \n";
return true;
}
void StokeInfo::runOnFunctions(BinaryContext &BC) {
outs() << "STOKE-INFO: begin of stoke pass\n";
std::ofstream Outfile;
if (!opts::StokeOutputDataFilename.empty()) {
Outfile.open(opts::StokeOutputDataFilename);
} else {
errs() << "STOKE-INFO: output file is required\n";
return;
}
// check some context meta data
LLVM_DEBUG(dbgs() << "\tTarget: " << BC.TheTarget->getName() << "\n");
LLVM_DEBUG(dbgs() << "\tTripleName " << BC.TripleName << "\n");
LLVM_DEBUG(dbgs() << "\tgetNumRegs " << BC.MRI->getNumRegs() << "\n");
BinaryFunctionCallGraph CG = buildCallGraph(BC);
RegAnalysis RA(BC, &BC.getBinaryFunctions(), &CG);
NumRegs = BC.MRI->getNumRegs();
assert(NumRegs > 0 && "STOKE-INFO: the target register number is incorrect!");
DefaultDefInMask.resize(NumRegs, false);
DefaultLiveOutMask.resize(NumRegs, false);
BC.MIB->getDefaultDefIn(DefaultDefInMask);
BC.MIB->getDefaultLiveOut(DefaultLiveOutMask);
getRegNameFromBitVec(BC, DefaultDefInMask);
getRegNameFromBitVec(BC, DefaultLiveOutMask);
StokeFuncInfo FuncInfo;
// analyze all functions
FuncInfo.printCsvHeader(Outfile);
for (auto &BF : BC.getBinaryFunctions()) {
DataflowInfoManager DInfo(BF.second, &RA, nullptr);
FuncInfo.reset();
if (checkFunction(BF.second, DInfo, RA, FuncInfo))
FuncInfo.printData(Outfile);
}
outs() << "STOKE-INFO: end of stoke pass\n";
}
} // namespace bolt
} // namespace llvm
|
