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
|
//===-- MPIChecker.cpp - Checker Entry Point Class --------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file defines the main class of MPI-Checker which serves as an entry
/// point. It is created once for each translation unit analysed.
/// The checker defines path-sensitive checks, to verify correct usage of the
/// MPI API.
///
//===----------------------------------------------------------------------===//
#include "MPIChecker.h"
#include "../ClangSACheckers.h"
namespace clang {
namespace ento {
namespace mpi {
void MPIChecker::checkDoubleNonblocking(const CallEvent &PreCallEvent,
CheckerContext &Ctx) const {
if (!FuncClassifier->isNonBlockingType(PreCallEvent.getCalleeIdentifier())) {
return;
}
const MemRegion *const MR =
PreCallEvent.getArgSVal(PreCallEvent.getNumArgs() - 1).getAsRegion();
if (!MR)
return;
const ElementRegion *const ER = dyn_cast<ElementRegion>(MR);
// The region must be typed, in order to reason about it.
if (!isa<TypedRegion>(MR) || (ER && !isa<TypedRegion>(ER->getSuperRegion())))
return;
ProgramStateRef State = Ctx.getState();
const Request *const Req = State->get<RequestMap>(MR);
// double nonblocking detected
if (Req && Req->CurrentState == Request::State::Nonblocking) {
ExplodedNode *ErrorNode = Ctx.generateNonFatalErrorNode();
BReporter.reportDoubleNonblocking(PreCallEvent, *Req, MR, ErrorNode, Ctx.getBugReporter());
Ctx.addTransition(ErrorNode->getState(), ErrorNode);
}
// no error
else {
State = State->set<RequestMap>(MR, Request::State::Nonblocking);
Ctx.addTransition(State);
}
}
void MPIChecker::checkUnmatchedWaits(const CallEvent &PreCallEvent,
CheckerContext &Ctx) const {
if (!FuncClassifier->isWaitType(PreCallEvent.getCalleeIdentifier()))
return;
const MemRegion *const MR = topRegionUsedByWait(PreCallEvent);
if (!MR)
return;
const ElementRegion *const ER = dyn_cast<ElementRegion>(MR);
// The region must be typed, in order to reason about it.
if (!isa<TypedRegion>(MR) || (ER && !isa<TypedRegion>(ER->getSuperRegion())))
return;
llvm::SmallVector<const MemRegion *, 2> ReqRegions;
allRegionsUsedByWait(ReqRegions, MR, PreCallEvent, Ctx);
if (ReqRegions.empty())
return;
ProgramStateRef State = Ctx.getState();
static CheckerProgramPointTag Tag("MPI-Checker", "UnmatchedWait");
ExplodedNode *ErrorNode{nullptr};
// Check all request regions used by the wait function.
for (const auto &ReqRegion : ReqRegions) {
const Request *const Req = State->get<RequestMap>(ReqRegion);
State = State->set<RequestMap>(ReqRegion, Request::State::Wait);
if (!Req) {
if (!ErrorNode) {
ErrorNode = Ctx.generateNonFatalErrorNode(State, &Tag);
State = ErrorNode->getState();
}
// A wait has no matching nonblocking call.
BReporter.reportUnmatchedWait(PreCallEvent, ReqRegion, ErrorNode, Ctx.getBugReporter());
}
}
if (!ErrorNode) {
Ctx.addTransition(State);
} else {
Ctx.addTransition(State, ErrorNode);
}
}
void MPIChecker::checkMissingWaits(SymbolReaper &SymReaper,
CheckerContext &Ctx) const {
if (!SymReaper.hasDeadSymbols())
return;
ProgramStateRef State = Ctx.getState();
const auto &Requests = State->get<RequestMap>();
if (Requests.isEmpty())
return;
static CheckerProgramPointTag Tag("MPI-Checker", "MissingWait");
ExplodedNode *ErrorNode{nullptr};
auto ReqMap = State->get<RequestMap>();
for (const auto &Req : ReqMap) {
if (!SymReaper.isLiveRegion(Req.first)) {
if (Req.second.CurrentState == Request::State::Nonblocking) {
if (!ErrorNode) {
ErrorNode = Ctx.generateNonFatalErrorNode(State, &Tag);
State = ErrorNode->getState();
}
BReporter.reportMissingWait(Req.second, Req.first, ErrorNode, Ctx.getBugReporter());
}
State = State->remove<RequestMap>(Req.first);
}
}
// Transition to update the state regarding removed requests.
if (!ErrorNode) {
Ctx.addTransition(State);
} else {
Ctx.addTransition(State, ErrorNode);
}
}
const MemRegion *MPIChecker::topRegionUsedByWait(const CallEvent &CE) const {
if (FuncClassifier->isMPI_Wait(CE.getCalleeIdentifier())) {
return CE.getArgSVal(0).getAsRegion();
} else if (FuncClassifier->isMPI_Waitall(CE.getCalleeIdentifier())) {
return CE.getArgSVal(1).getAsRegion();
} else {
return (const MemRegion *)nullptr;
}
}
void MPIChecker::allRegionsUsedByWait(
llvm::SmallVector<const MemRegion *, 2> &ReqRegions,
const MemRegion *const MR, const CallEvent &CE, CheckerContext &Ctx) const {
MemRegionManager *const RegionManager = MR->getMemRegionManager();
if (FuncClassifier->isMPI_Waitall(CE.getCalleeIdentifier())) {
const MemRegion *SuperRegion{nullptr};
if (const ElementRegion *const ER = MR->getAs<ElementRegion>()) {
SuperRegion = ER->getSuperRegion();
}
// A single request is passed to MPI_Waitall.
if (!SuperRegion) {
ReqRegions.push_back(MR);
return;
}
const auto &Size = Ctx.getStoreManager().getSizeInElements(
Ctx.getState(), SuperRegion,
CE.getArgExpr(1)->getType()->getPointeeType());
const llvm::APSInt &ArrSize = Size.getAs<nonloc::ConcreteInt>()->getValue();
for (size_t i = 0; i < ArrSize; ++i) {
const NonLoc Idx = Ctx.getSValBuilder().makeArrayIndex(i);
const ElementRegion *const ER = RegionManager->getElementRegion(
CE.getArgExpr(1)->getType()->getPointeeType(), Idx, SuperRegion,
Ctx.getASTContext());
ReqRegions.push_back(ER->getAs<MemRegion>());
}
} else if (FuncClassifier->isMPI_Wait(CE.getCalleeIdentifier())) {
ReqRegions.push_back(MR);
}
}
} // end of namespace: mpi
} // end of namespace: ento
} // end of namespace: clang
// Registers the checker for static analysis.
void clang::ento::registerMPIChecker(CheckerManager &MGR) {
MGR.registerChecker<clang::ento::mpi::MPIChecker>();
}
|
