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
|
//===- ModuleSummaryAnalysis.cpp - Module summary index builder -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass builds a ModuleSummaryIndex object for the module, to be written
// to bitcode or LLVM assembly.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/ModuleSummaryAnalysis.h"
#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/ValueSymbolTable.h"
#include "llvm/Pass.h"
using namespace llvm;
#define DEBUG_TYPE "module-summary-analysis"
// Walk through the operands of a given User via worklist iteration and populate
// the set of GlobalValue references encountered. Invoked either on an
// Instruction or a GlobalVariable (which walks its initializer).
static void findRefEdges(const User *CurUser, DenseSet<const Value *> &RefEdges,
SmallPtrSet<const User *, 8> &Visited) {
SmallVector<const User *, 32> Worklist;
Worklist.push_back(CurUser);
while (!Worklist.empty()) {
const User *U = Worklist.pop_back_val();
if (!Visited.insert(U).second)
continue;
ImmutableCallSite CS(U);
for (const auto &OI : U->operands()) {
const User *Operand = dyn_cast<User>(OI);
if (!Operand)
continue;
if (isa<BlockAddress>(Operand))
continue;
if (isa<GlobalValue>(Operand)) {
// We have a reference to a global value. This should be added to
// the reference set unless it is a callee. Callees are handled
// specially by WriteFunction and are added to a separate list.
if (!(CS && CS.isCallee(&OI)))
RefEdges.insert(Operand);
continue;
}
Worklist.push_back(Operand);
}
}
}
void ModuleSummaryIndexBuilder::computeFunctionInfo(const Function &F,
BlockFrequencyInfo *BFI) {
// Summary not currently supported for anonymous functions, they must
// be renamed.
if (!F.hasName())
return;
unsigned NumInsts = 0;
// Map from callee ValueId to profile count. Used to accumulate profile
// counts for all static calls to a given callee.
DenseMap<const Value *, CalleeInfo> CallGraphEdges;
DenseSet<const Value *> RefEdges;
SmallPtrSet<const User *, 8> Visited;
for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E;
++I) {
if (!isa<DbgInfoIntrinsic>(I))
++NumInsts;
if (auto CS = ImmutableCallSite(&*I)) {
auto *CalledFunction = CS.getCalledFunction();
if (CalledFunction && CalledFunction->hasName() &&
!CalledFunction->isIntrinsic()) {
auto ScaledCount = BFI ? BFI->getBlockProfileCount(&*BB) : None;
auto *CalleeId =
M->getValueSymbolTable().lookup(CalledFunction->getName());
CallGraphEdges[CalleeId] +=
(ScaledCount ? ScaledCount.getValue() : 0);
}
}
findRefEdges(&*I, RefEdges, Visited);
}
std::unique_ptr<FunctionSummary> FuncSummary =
llvm::make_unique<FunctionSummary>(F.getLinkage(), NumInsts);
FuncSummary->addCallGraphEdges(CallGraphEdges);
FuncSummary->addRefEdges(RefEdges);
std::unique_ptr<GlobalValueInfo> GVInfo =
llvm::make_unique<GlobalValueInfo>(0, std::move(FuncSummary));
Index->addGlobalValueInfo(F.getName(), std::move(GVInfo));
}
void ModuleSummaryIndexBuilder::computeVariableInfo(const GlobalVariable &V) {
DenseSet<const Value *> RefEdges;
SmallPtrSet<const User *, 8> Visited;
findRefEdges(&V, RefEdges, Visited);
std::unique_ptr<GlobalVarSummary> GVarSummary =
llvm::make_unique<GlobalVarSummary>(V.getLinkage());
GVarSummary->addRefEdges(RefEdges);
std::unique_ptr<GlobalValueInfo> GVInfo =
llvm::make_unique<GlobalValueInfo>(0, std::move(GVarSummary));
Index->addGlobalValueInfo(V.getName(), std::move(GVInfo));
}
ModuleSummaryIndexBuilder::ModuleSummaryIndexBuilder(
const Module *M,
std::function<BlockFrequencyInfo *(const Function &F)> Ftor)
: Index(llvm::make_unique<ModuleSummaryIndex>()), M(M) {
// Compute summaries for all functions defined in module, and save in the
// index.
for (auto &F : *M) {
if (F.isDeclaration())
continue;
BlockFrequencyInfo *BFI = nullptr;
std::unique_ptr<BlockFrequencyInfo> BFIPtr;
if (Ftor)
BFI = Ftor(F);
else if (F.getEntryCount().hasValue()) {
LoopInfo LI{DominatorTree(const_cast<Function &>(F))};
BranchProbabilityInfo BPI{F, LI};
BFIPtr = llvm::make_unique<BlockFrequencyInfo>(F, BPI, LI);
BFI = BFIPtr.get();
}
computeFunctionInfo(F, BFI);
}
// Compute summaries for all variables defined in module, and save in the
// index.
for (const GlobalVariable &G : M->globals()) {
if (G.isDeclaration())
continue;
computeVariableInfo(G);
}
}
char ModuleSummaryIndexWrapperPass::ID = 0;
INITIALIZE_PASS_BEGIN(ModuleSummaryIndexWrapperPass, "module-summary-analysis",
"Module Summary Analysis", false, true)
INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)
INITIALIZE_PASS_END(ModuleSummaryIndexWrapperPass, "module-summary-analysis",
"Module Summary Analysis", false, true)
ModulePass *llvm::createModuleSummaryIndexWrapperPass() {
return new ModuleSummaryIndexWrapperPass();
}
ModuleSummaryIndexWrapperPass::ModuleSummaryIndexWrapperPass()
: ModulePass(ID) {
initializeModuleSummaryIndexWrapperPassPass(*PassRegistry::getPassRegistry());
}
bool ModuleSummaryIndexWrapperPass::runOnModule(Module &M) {
IndexBuilder = llvm::make_unique<ModuleSummaryIndexBuilder>(
&M, [this](const Function &F) {
return &(this->getAnalysis<BlockFrequencyInfoWrapperPass>(
*const_cast<Function *>(&F))
.getBFI());
});
return false;
}
bool ModuleSummaryIndexWrapperPass::doFinalization(Module &M) {
IndexBuilder.reset();
return false;
}
void ModuleSummaryIndexWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<BlockFrequencyInfoWrapperPass>();
}
|
