|
150
|
1 //===- ThreadSafety.cpp ---------------------------------------------------===//
|
|
|
2 //
|
|
|
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
|
4 // See https://llvm.org/LICENSE.txt for license information.
|
|
|
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
|
6 //
|
|
|
7 //===----------------------------------------------------------------------===//
|
|
|
8 //
|
|
|
9 // A intra-procedural analysis for thread safety (e.g. deadlocks and race
|
|
|
10 // conditions), based off of an annotation system.
|
|
|
11 //
|
|
|
12 // See http://clang.llvm.org/docs/ThreadSafetyAnalysis.html
|
|
|
13 // for more information.
|
|
|
14 //
|
|
|
15 //===----------------------------------------------------------------------===//
|
|
|
16
|
|
|
17 #include "clang/Analysis/Analyses/ThreadSafety.h"
|
|
|
18 #include "clang/AST/Attr.h"
|
|
|
19 #include "clang/AST/Decl.h"
|
|
|
20 #include "clang/AST/DeclCXX.h"
|
|
|
21 #include "clang/AST/DeclGroup.h"
|
|
|
22 #include "clang/AST/Expr.h"
|
|
|
23 #include "clang/AST/ExprCXX.h"
|
|
|
24 #include "clang/AST/OperationKinds.h"
|
|
|
25 #include "clang/AST/Stmt.h"
|
|
|
26 #include "clang/AST/StmtVisitor.h"
|
|
|
27 #include "clang/AST/Type.h"
|
|
|
28 #include "clang/Analysis/Analyses/PostOrderCFGView.h"
|
|
|
29 #include "clang/Analysis/Analyses/ThreadSafetyCommon.h"
|
|
|
30 #include "clang/Analysis/Analyses/ThreadSafetyTIL.h"
|
|
|
31 #include "clang/Analysis/Analyses/ThreadSafetyTraverse.h"
|
|
|
32 #include "clang/Analysis/Analyses/ThreadSafetyUtil.h"
|
|
|
33 #include "clang/Analysis/AnalysisDeclContext.h"
|
|
|
34 #include "clang/Analysis/CFG.h"
|
|
|
35 #include "clang/Basic/Builtins.h"
|
|
|
36 #include "clang/Basic/LLVM.h"
|
|
|
37 #include "clang/Basic/OperatorKinds.h"
|
|
|
38 #include "clang/Basic/SourceLocation.h"
|
|
|
39 #include "clang/Basic/Specifiers.h"
|
|
|
40 #include "llvm/ADT/ArrayRef.h"
|
|
|
41 #include "llvm/ADT/DenseMap.h"
|
|
|
42 #include "llvm/ADT/ImmutableMap.h"
|
|
|
43 #include "llvm/ADT/Optional.h"
|
|
|
44 #include "llvm/ADT/PointerIntPair.h"
|
|
|
45 #include "llvm/ADT/STLExtras.h"
|
|
|
46 #include "llvm/ADT/SmallVector.h"
|
|
|
47 #include "llvm/ADT/StringRef.h"
|
|
|
48 #include "llvm/Support/Allocator.h"
|
|
|
49 #include "llvm/Support/Casting.h"
|
|
|
50 #include "llvm/Support/ErrorHandling.h"
|
|
|
51 #include "llvm/Support/raw_ostream.h"
|
|
|
52 #include <algorithm>
|
|
|
53 #include <cassert>
|
|
|
54 #include <functional>
|
|
|
55 #include <iterator>
|
|
|
56 #include <memory>
|
|
|
57 #include <string>
|
|
|
58 #include <type_traits>
|
|
|
59 #include <utility>
|
|
|
60 #include <vector>
|
|
|
61
|
|
|
62 using namespace clang;
|
|
|
63 using namespace threadSafety;
|
|
|
64
|
|
|
65 // Key method definition
|
|
|
66 ThreadSafetyHandler::~ThreadSafetyHandler() = default;
|
|
|
67
|
|
|
68 /// Issue a warning about an invalid lock expression
|
|
|
69 static void warnInvalidLock(ThreadSafetyHandler &Handler,
|
|
|
70 const Expr *MutexExp, const NamedDecl *D,
|
|
|
71 const Expr *DeclExp, StringRef Kind) {
|
|
|
72 SourceLocation Loc;
|
|
|
73 if (DeclExp)
|
|
|
74 Loc = DeclExp->getExprLoc();
|
|
|
75
|
|
|
76 // FIXME: add a note about the attribute location in MutexExp or D
|
|
|
77 if (Loc.isValid())
|
|
|
78 Handler.handleInvalidLockExp(Kind, Loc);
|
|
|
79 }
|
|
|
80
|
|
|
81 namespace {
|
|
|
82
|
|
|
83 /// A set of CapabilityExpr objects, which are compiled from thread safety
|
|
|
84 /// attributes on a function.
|
|
|
85 class CapExprSet : public SmallVector<CapabilityExpr, 4> {
|
|
|
86 public:
|
|
|
87 /// Push M onto list, but discard duplicates.
|
|
|
88 void push_back_nodup(const CapabilityExpr &CapE) {
|
|
|
89 iterator It = std::find_if(begin(), end(),
|
|
|
90 [=](const CapabilityExpr &CapE2) {
|
|
|
91 return CapE.equals(CapE2);
|
|
|
92 });
|
|
|
93 if (It == end())
|
|
|
94 push_back(CapE);
|
|
|
95 }
|
|
|
96 };
|
|
|
97
|
|
|
98 class FactManager;
|
|
|
99 class FactSet;
|
|
|
100
|
|
|
101 /// This is a helper class that stores a fact that is known at a
|
|
|
102 /// particular point in program execution. Currently, a fact is a capability,
|
|
|
103 /// along with additional information, such as where it was acquired, whether
|
|
|
104 /// it is exclusive or shared, etc.
|
|
|
105 ///
|
|
|
106 /// FIXME: this analysis does not currently support re-entrant locking.
|
|
|
107 class FactEntry : public CapabilityExpr {
|
|
|
108 private:
|
|
|
109 /// Exclusive or shared.
|
|
|
110 LockKind LKind;
|
|
|
111
|
|
|
112 /// Where it was acquired.
|
|
|
113 SourceLocation AcquireLoc;
|
|
|
114
|
|
|
115 /// True if the lock was asserted.
|
|
|
116 bool Asserted;
|
|
|
117
|
|
|
118 /// True if the lock was declared.
|
|
|
119 bool Declared;
|
|
|
120
|
|
|
121 public:
|
|
|
122 FactEntry(const CapabilityExpr &CE, LockKind LK, SourceLocation Loc,
|
|
|
123 bool Asrt, bool Declrd = false)
|
|
|
124 : CapabilityExpr(CE), LKind(LK), AcquireLoc(Loc), Asserted(Asrt),
|
|
|
125 Declared(Declrd) {}
|
|
|
126 virtual ~FactEntry() = default;
|
|
|
127
|
|
|
128 LockKind kind() const { return LKind; }
|
|
|
129 SourceLocation loc() const { return AcquireLoc; }
|
|
|
130 bool asserted() const { return Asserted; }
|
|
|
131 bool declared() const { return Declared; }
|
|
|
132
|
|
|
133 void setDeclared(bool D) { Declared = D; }
|
|
|
134
|
|
|
135 virtual void
|
|
|
136 handleRemovalFromIntersection(const FactSet &FSet, FactManager &FactMan,
|
|
|
137 SourceLocation JoinLoc, LockErrorKind LEK,
|
|
|
138 ThreadSafetyHandler &Handler) const = 0;
|
|
|
139 virtual void handleLock(FactSet &FSet, FactManager &FactMan,
|
|
|
140 const FactEntry &entry, ThreadSafetyHandler &Handler,
|
|
|
141 StringRef DiagKind) const = 0;
|
|
|
142 virtual void handleUnlock(FactSet &FSet, FactManager &FactMan,
|
|
|
143 const CapabilityExpr &Cp, SourceLocation UnlockLoc,
|
|
|
144 bool FullyRemove, ThreadSafetyHandler &Handler,
|
|
|
145 StringRef DiagKind) const = 0;
|
|
|
146
|
|
|
147 // Return true if LKind >= LK, where exclusive > shared
|
|
|
148 bool isAtLeast(LockKind LK) const {
|
|
|
149 return (LKind == LK_Exclusive) || (LK == LK_Shared);
|
|
|
150 }
|
|
|
151 };
|
|
|
152
|
|
|
153 using FactID = unsigned short;
|
|
|
154
|
|
|
155 /// FactManager manages the memory for all facts that are created during
|
|
|
156 /// the analysis of a single routine.
|
|
|
157 class FactManager {
|
|
|
158 private:
|
|
|
159 std::vector<std::unique_ptr<const FactEntry>> Facts;
|
|
|
160
|
|
|
161 public:
|
|
|
162 FactID newFact(std::unique_ptr<FactEntry> Entry) {
|
|
|
163 Facts.push_back(std::move(Entry));
|
|
|
164 return static_cast<unsigned short>(Facts.size() - 1);
|
|
|
165 }
|
|
|
166
|
|
|
167 const FactEntry &operator[](FactID F) const { return *Facts[F]; }
|
|
|
168 };
|
|
|
169
|
|
|
170 /// A FactSet is the set of facts that are known to be true at a
|
|
|
171 /// particular program point. FactSets must be small, because they are
|
|
|
172 /// frequently copied, and are thus implemented as a set of indices into a
|
|
|
173 /// table maintained by a FactManager. A typical FactSet only holds 1 or 2
|
|
|
174 /// locks, so we can get away with doing a linear search for lookup. Note
|
|
|
175 /// that a hashtable or map is inappropriate in this case, because lookups
|
|
|
176 /// may involve partial pattern matches, rather than exact matches.
|
|
|
177 class FactSet {
|
|
|
178 private:
|
|
|
179 using FactVec = SmallVector<FactID, 4>;
|
|
|
180
|
|
|
181 FactVec FactIDs;
|
|
|
182
|
|
|
183 public:
|
|
|
184 using iterator = FactVec::iterator;
|
|
|
185 using const_iterator = FactVec::const_iterator;
|
|
|
186
|
|
|
187 iterator begin() { return FactIDs.begin(); }
|
|
|
188 const_iterator begin() const { return FactIDs.begin(); }
|
|
|
189
|
|
|
190 iterator end() { return FactIDs.end(); }
|
|
|
191 const_iterator end() const { return FactIDs.end(); }
|
|
|
192
|
|
|
193 bool isEmpty() const { return FactIDs.size() == 0; }
|
|
|
194
|
|
|
195 // Return true if the set contains only negative facts
|
|
|
196 bool isEmpty(FactManager &FactMan) const {
|
|
|
197 for (const auto FID : *this) {
|
|
|
198 if (!FactMan[FID].negative())
|
|
|
199 return false;
|
|
|
200 }
|
|
|
201 return true;
|
|
|
202 }
|
|
|
203
|
|
|
204 void addLockByID(FactID ID) { FactIDs.push_back(ID); }
|
|
|
205
|
|
|
206 FactID addLock(FactManager &FM, std::unique_ptr<FactEntry> Entry) {
|
|
|
207 FactID F = FM.newFact(std::move(Entry));
|
|
|
208 FactIDs.push_back(F);
|
|
|
209 return F;
|
|
|
210 }
|
|
|
211
|
|
|
212 bool removeLock(FactManager& FM, const CapabilityExpr &CapE) {
|
|
|
213 unsigned n = FactIDs.size();
|
|
|
214 if (n == 0)
|
|
|
215 return false;
|
|
|
216
|
|
|
217 for (unsigned i = 0; i < n-1; ++i) {
|
|
|
218 if (FM[FactIDs[i]].matches(CapE)) {
|
|
|
219 FactIDs[i] = FactIDs[n-1];
|
|
|
220 FactIDs.pop_back();
|
|
|
221 return true;
|
|
|
222 }
|
|
|
223 }
|
|
|
224 if (FM[FactIDs[n-1]].matches(CapE)) {
|
|
|
225 FactIDs.pop_back();
|
|
|
226 return true;
|
|
|
227 }
|
|
|
228 return false;
|
|
|
229 }
|
|
|
230
|
|
|
231 iterator findLockIter(FactManager &FM, const CapabilityExpr &CapE) {
|
|
|
232 return std::find_if(begin(), end(), [&](FactID ID) {
|
|
|
233 return FM[ID].matches(CapE);
|
|
|
234 });
|
|
|
235 }
|
|
|
236
|
|
|
237 const FactEntry *findLock(FactManager &FM, const CapabilityExpr &CapE) const {
|
|
|
238 auto I = std::find_if(begin(), end(), [&](FactID ID) {
|
|
|
239 return FM[ID].matches(CapE);
|
|
|
240 });
|
|
|
241 return I != end() ? &FM[*I] : nullptr;
|
|
|
242 }
|
|
|
243
|
|
|
244 const FactEntry *findLockUniv(FactManager &FM,
|
|
|
245 const CapabilityExpr &CapE) const {
|
|
|
246 auto I = std::find_if(begin(), end(), [&](FactID ID) -> bool {
|
|
|
247 return FM[ID].matchesUniv(CapE);
|
|
|
248 });
|
|
|
249 return I != end() ? &FM[*I] : nullptr;
|
|
|
250 }
|
|
|
251
|
|
|
252 const FactEntry *findPartialMatch(FactManager &FM,
|
|
|
253 const CapabilityExpr &CapE) const {
|
|
|
254 auto I = std::find_if(begin(), end(), [&](FactID ID) -> bool {
|
|
|
255 return FM[ID].partiallyMatches(CapE);
|
|
|
256 });
|
|
|
257 return I != end() ? &FM[*I] : nullptr;
|
|
|
258 }
|
|
|
259
|
|
|
260 bool containsMutexDecl(FactManager &FM, const ValueDecl* Vd) const {
|
|
|
261 auto I = std::find_if(begin(), end(), [&](FactID ID) -> bool {
|
|
|
262 return FM[ID].valueDecl() == Vd;
|
|
|
263 });
|
|
|
264 return I != end();
|
|
|
265 }
|
|
|
266 };
|
|
|
267
|
|
|
268 class ThreadSafetyAnalyzer;
|
|
|
269
|
|
|
270 } // namespace
|
|
|
271
|
|
|
272 namespace clang {
|
|
|
273 namespace threadSafety {
|
|
|
274
|
|
|
275 class BeforeSet {
|
|
|
276 private:
|
|
|
277 using BeforeVect = SmallVector<const ValueDecl *, 4>;
|
|
|
278
|
|
|
279 struct BeforeInfo {
|
|
|
280 BeforeVect Vect;
|
|
|
281 int Visited = 0;
|
|
|
282
|
|
|
283 BeforeInfo() = default;
|
|
|
284 BeforeInfo(BeforeInfo &&) = default;
|
|
|
285 };
|
|
|
286
|
|
|
287 using BeforeMap =
|
|
|
288 llvm::DenseMap<const ValueDecl *, std::unique_ptr<BeforeInfo>>;
|
|
|
289 using CycleMap = llvm::DenseMap<const ValueDecl *, bool>;
|
|
|
290
|
|
|
291 public:
|
|
|
292 BeforeSet() = default;
|
|
|
293
|
|
|
294 BeforeInfo* insertAttrExprs(const ValueDecl* Vd,
|
|
|
295 ThreadSafetyAnalyzer& Analyzer);
|
|
|
296
|
|
|
297 BeforeInfo *getBeforeInfoForDecl(const ValueDecl *Vd,
|
|
|
298 ThreadSafetyAnalyzer &Analyzer);
|
|
|
299
|
|
|
300 void checkBeforeAfter(const ValueDecl* Vd,
|
|
|
301 const FactSet& FSet,
|
|
|
302 ThreadSafetyAnalyzer& Analyzer,
|
|
|
303 SourceLocation Loc, StringRef CapKind);
|
|
|
304
|
|
|
305 private:
|
|
|
306 BeforeMap BMap;
|
|
|
307 CycleMap CycMap;
|
|
|
308 };
|
|
|
309
|
|
|
310 } // namespace threadSafety
|
|
|
311 } // namespace clang
|
|
|
312
|
|
|
313 namespace {
|
|
|
314
|
|
|
315 class LocalVariableMap;
|
|
|
316
|
|
|
317 using LocalVarContext = llvm::ImmutableMap<const NamedDecl *, unsigned>;
|
|
|
318
|
|
|
319 /// A side (entry or exit) of a CFG node.
|
|
|
320 enum CFGBlockSide { CBS_Entry, CBS_Exit };
|
|
|
321
|
|
|
322 /// CFGBlockInfo is a struct which contains all the information that is
|
|
|
323 /// maintained for each block in the CFG. See LocalVariableMap for more
|
|
|
324 /// information about the contexts.
|
|
|
325 struct CFGBlockInfo {
|
|
|
326 // Lockset held at entry to block
|
|
|
327 FactSet EntrySet;
|
|
|
328
|
|
|
329 // Lockset held at exit from block
|
|
|
330 FactSet ExitSet;
|
|
|
331
|
|
|
332 // Context held at entry to block
|
|
|
333 LocalVarContext EntryContext;
|
|
|
334
|
|
|
335 // Context held at exit from block
|
|
|
336 LocalVarContext ExitContext;
|
|
|
337
|
|
|
338 // Location of first statement in block
|
|
|
339 SourceLocation EntryLoc;
|
|
|
340
|
|
|
341 // Location of last statement in block.
|
|
|
342 SourceLocation ExitLoc;
|
|
|
343
|
|
|
344 // Used to replay contexts later
|
|
|
345 unsigned EntryIndex;
|
|
|
346
|
|
|
347 // Is this block reachable?
|
|
|
348 bool Reachable = false;
|
|
|
349
|
|
|
350 const FactSet &getSet(CFGBlockSide Side) const {
|
|
|
351 return Side == CBS_Entry ? EntrySet : ExitSet;
|
|
|
352 }
|
|
|
353
|
|
|
354 SourceLocation getLocation(CFGBlockSide Side) const {
|
|
|
355 return Side == CBS_Entry ? EntryLoc : ExitLoc;
|
|
|
356 }
|
|
|
357
|
|
|
358 private:
|
|
|
359 CFGBlockInfo(LocalVarContext EmptyCtx)
|
|
|
360 : EntryContext(EmptyCtx), ExitContext(EmptyCtx) {}
|
|
|
361
|
|
|
362 public:
|
|
|
363 static CFGBlockInfo getEmptyBlockInfo(LocalVariableMap &M);
|
|
|
364 };
|
|
|
365
|
|
|
366 // A LocalVariableMap maintains a map from local variables to their currently
|
|
|
367 // valid definitions. It provides SSA-like functionality when traversing the
|
|
|
368 // CFG. Like SSA, each definition or assignment to a variable is assigned a
|
|
|
369 // unique name (an integer), which acts as the SSA name for that definition.
|
|
|
370 // The total set of names is shared among all CFG basic blocks.
|
|
|
371 // Unlike SSA, we do not rewrite expressions to replace local variables declrefs
|
|
|
372 // with their SSA-names. Instead, we compute a Context for each point in the
|
|
|
373 // code, which maps local variables to the appropriate SSA-name. This map
|
|
|
374 // changes with each assignment.
|
|
|
375 //
|
|
|
376 // The map is computed in a single pass over the CFG. Subsequent analyses can
|
|
|
377 // then query the map to find the appropriate Context for a statement, and use
|
|
|
378 // that Context to look up the definitions of variables.
|
|
|
379 class LocalVariableMap {
|
|
|
380 public:
|
|
|
381 using Context = LocalVarContext;
|
|
|
382
|
|
|
383 /// A VarDefinition consists of an expression, representing the value of the
|
|
|
384 /// variable, along with the context in which that expression should be
|
|
|
385 /// interpreted. A reference VarDefinition does not itself contain this
|
|
|
386 /// information, but instead contains a pointer to a previous VarDefinition.
|
|
|
387 struct VarDefinition {
|
|
|
388 public:
|
|
|
389 friend class LocalVariableMap;
|
|
|
390
|
|
|
391 // The original declaration for this variable.
|
|
|
392 const NamedDecl *Dec;
|
|
|
393
|
|
|
394 // The expression for this variable, OR
|
|
|
395 const Expr *Exp = nullptr;
|
|
|
396
|
|
|
397 // Reference to another VarDefinition
|
|
|
398 unsigned Ref = 0;
|
|
|
399
|
|
|
400 // The map with which Exp should be interpreted.
|
|
|
401 Context Ctx;
|
|
|
402
|
|
|
403 bool isReference() { return !Exp; }
|
|
|
404
|
|
|
405 private:
|
|
|
406 // Create ordinary variable definition
|
|
|
407 VarDefinition(const NamedDecl *D, const Expr *E, Context C)
|
|
|
408 : Dec(D), Exp(E), Ctx(C) {}
|
|
|
409
|
|
|
410 // Create reference to previous definition
|
|
|
411 VarDefinition(const NamedDecl *D, unsigned R, Context C)
|
|
|
412 : Dec(D), Ref(R), Ctx(C) {}
|
|
|
413 };
|
|
|
414
|
|
|
415 private:
|
|
|
416 Context::Factory ContextFactory;
|
|
|
417 std::vector<VarDefinition> VarDefinitions;
|
|
|
418 std::vector<unsigned> CtxIndices;
|
|
|
419 std::vector<std::pair<const Stmt *, Context>> SavedContexts;
|
|
|
420
|
|
|
421 public:
|
|
|
422 LocalVariableMap() {
|
|
|
423 // index 0 is a placeholder for undefined variables (aka phi-nodes).
|
|
|
424 VarDefinitions.push_back(VarDefinition(nullptr, 0u, getEmptyContext()));
|
|
|
425 }
|
|
|
426
|
|
|
427 /// Look up a definition, within the given context.
|
|
|
428 const VarDefinition* lookup(const NamedDecl *D, Context Ctx) {
|
|
|
429 const unsigned *i = Ctx.lookup(D);
|
|
|
430 if (!i)
|
|
|
431 return nullptr;
|
|
|
432 assert(*i < VarDefinitions.size());
|
|
|
433 return &VarDefinitions[*i];
|
|
|
434 }
|
|
|
435
|
|
|
436 /// Look up the definition for D within the given context. Returns
|
|
|
437 /// NULL if the expression is not statically known. If successful, also
|
|
|
438 /// modifies Ctx to hold the context of the return Expr.
|
|
|
439 const Expr* lookupExpr(const NamedDecl *D, Context &Ctx) {
|
|
|
440 const unsigned *P = Ctx.lookup(D);
|
|
|
441 if (!P)
|
|
|
442 return nullptr;
|
|
|
443
|
|
|
444 unsigned i = *P;
|
|
|
445 while (i > 0) {
|
|
|
446 if (VarDefinitions[i].Exp) {
|
|
|
447 Ctx = VarDefinitions[i].Ctx;
|
|
|
448 return VarDefinitions[i].Exp;
|
|
|
449 }
|
|
|
450 i = VarDefinitions[i].Ref;
|
|
|
451 }
|
|
|
452 return nullptr;
|
|
|
453 }
|
|
|
454
|
|
|
455 Context getEmptyContext() { return ContextFactory.getEmptyMap(); }
|
|
|
456
|
|
|
457 /// Return the next context after processing S. This function is used by
|
|
|
458 /// clients of the class to get the appropriate context when traversing the
|
|
|
459 /// CFG. It must be called for every assignment or DeclStmt.
|
|
|
460 Context getNextContext(unsigned &CtxIndex, const Stmt *S, Context C) {
|
|
|
461 if (SavedContexts[CtxIndex+1].first == S) {
|
|
|
462 CtxIndex++;
|
|
|
463 Context Result = SavedContexts[CtxIndex].second;
|
|
|
464 return Result;
|
|
|
465 }
|
|
|
466 return C;
|
|
|
467 }
|
|
|
468
|
|
|
469 void dumpVarDefinitionName(unsigned i) {
|
|
|
470 if (i == 0) {
|
|
|
471 llvm::errs() << "Undefined";
|
|
|
472 return;
|
|
|
473 }
|
|
|
474 const NamedDecl *Dec = VarDefinitions[i].Dec;
|
|
|
475 if (!Dec) {
|
|
|
476 llvm::errs() << "<<NULL>>";
|
|
|
477 return;
|
|
|
478 }
|
|
|
479 Dec->printName(llvm::errs());
|
|
|
480 llvm::errs() << "." << i << " " << ((const void*) Dec);
|
|
|
481 }
|
|
|
482
|
|
|
483 /// Dumps an ASCII representation of the variable map to llvm::errs()
|
|
|
484 void dump() {
|
|
|
485 for (unsigned i = 1, e = VarDefinitions.size(); i < e; ++i) {
|
|
|
486 const Expr *Exp = VarDefinitions[i].Exp;
|
|
|
487 unsigned Ref = VarDefinitions[i].Ref;
|
|
|
488
|
|
|
489 dumpVarDefinitionName(i);
|
|
|
490 llvm::errs() << " = ";
|
|
|
491 if (Exp) Exp->dump();
|
|
|
492 else {
|
|
|
493 dumpVarDefinitionName(Ref);
|
|
|
494 llvm::errs() << "\n";
|
|
|
495 }
|
|
|
496 }
|
|
|
497 }
|
|
|
498
|
|
|
499 /// Dumps an ASCII representation of a Context to llvm::errs()
|
|
|
500 void dumpContext(Context C) {
|
|
|
501 for (Context::iterator I = C.begin(), E = C.end(); I != E; ++I) {
|
|
|
502 const NamedDecl *D = I.getKey();
|
|
|
503 D->printName(llvm::errs());
|
|
|
504 const unsigned *i = C.lookup(D);
|
|
|
505 llvm::errs() << " -> ";
|
|
|
506 dumpVarDefinitionName(*i);
|
|
|
507 llvm::errs() << "\n";
|
|
|
508 }
|
|
|
509 }
|
|
|
510
|
|
|
511 /// Builds the variable map.
|
|
|
512 void traverseCFG(CFG *CFGraph, const PostOrderCFGView *SortedGraph,
|
|
|
513 std::vector<CFGBlockInfo> &BlockInfo);
|
|
|
514
|
|
|
515 protected:
|
|
|
516 friend class VarMapBuilder;
|
|
|
517
|
|
|
518 // Get the current context index
|
|
|
519 unsigned getContextIndex() { return SavedContexts.size()-1; }
|
|
|
520
|
|
|
521 // Save the current context for later replay
|
|
|
522 void saveContext(const Stmt *S, Context C) {
|
|
|
523 SavedContexts.push_back(std::make_pair(S, C));
|
|
|
524 }
|
|
|
525
|
|
|
526 // Adds a new definition to the given context, and returns a new context.
|
|
|
527 // This method should be called when declaring a new variable.
|
|
|
528 Context addDefinition(const NamedDecl *D, const Expr *Exp, Context Ctx) {
|
|
|
529 assert(!Ctx.contains(D));
|
|
|
530 unsigned newID = VarDefinitions.size();
|
|
|
531 Context NewCtx = ContextFactory.add(Ctx, D, newID);
|
|
|
532 VarDefinitions.push_back(VarDefinition(D, Exp, Ctx));
|
|
|
533 return NewCtx;
|
|
|
534 }
|
|
|
535
|
|
|
536 // Add a new reference to an existing definition.
|
|
|
537 Context addReference(const NamedDecl *D, unsigned i, Context Ctx) {
|
|
|
538 unsigned newID = VarDefinitions.size();
|
|
|
539 Context NewCtx = ContextFactory.add(Ctx, D, newID);
|
|
|
540 VarDefinitions.push_back(VarDefinition(D, i, Ctx));
|
|
|
541 return NewCtx;
|
|
|
542 }
|
|
|
543
|
|
|
544 // Updates a definition only if that definition is already in the map.
|
|
|
545 // This method should be called when assigning to an existing variable.
|
|
|
546 Context updateDefinition(const NamedDecl *D, Expr *Exp, Context Ctx) {
|
|
|
547 if (Ctx.contains(D)) {
|
|
|
548 unsigned newID = VarDefinitions.size();
|
|
|
549 Context NewCtx = ContextFactory.remove(Ctx, D);
|
|
|
550 NewCtx = ContextFactory.add(NewCtx, D, newID);
|
|
|
551 VarDefinitions.push_back(VarDefinition(D, Exp, Ctx));
|
|
|
552 return NewCtx;
|
|
|
553 }
|
|
|
554 return Ctx;
|
|
|
555 }
|
|
|
556
|
|
|
557 // Removes a definition from the context, but keeps the variable name
|
|
|
558 // as a valid variable. The index 0 is a placeholder for cleared definitions.
|
|
|
559 Context clearDefinition(const NamedDecl *D, Context Ctx) {
|
|
|
560 Context NewCtx = Ctx;
|
|
|
561 if (NewCtx.contains(D)) {
|
|
|
562 NewCtx = ContextFactory.remove(NewCtx, D);
|
|
|
563 NewCtx = ContextFactory.add(NewCtx, D, 0);
|
|
|
564 }
|
|
|
565 return NewCtx;
|
|
|
566 }
|
|
|
567
|
|
|
568 // Remove a definition entirely frmo the context.
|
|
|
569 Context removeDefinition(const NamedDecl *D, Context Ctx) {
|
|
|
570 Context NewCtx = Ctx;
|
|
|
571 if (NewCtx.contains(D)) {
|
|
|
572 NewCtx = ContextFactory.remove(NewCtx, D);
|
|
|
573 }
|
|
|
574 return NewCtx;
|
|
|
575 }
|
|
|
576
|
|
|
577 Context intersectContexts(Context C1, Context C2);
|
|
|
578 Context createReferenceContext(Context C);
|
|
|
579 void intersectBackEdge(Context C1, Context C2);
|
|
|
580 };
|
|
|
581
|
|
|
582 } // namespace
|
|
|
583
|
|
|
584 // This has to be defined after LocalVariableMap.
|
|
|
585 CFGBlockInfo CFGBlockInfo::getEmptyBlockInfo(LocalVariableMap &M) {
|
|
|
586 return CFGBlockInfo(M.getEmptyContext());
|
|
|
587 }
|
|
|
588
|
|
|
589 namespace {
|
|
|
590
|
|
|
591 /// Visitor which builds a LocalVariableMap
|
|
|
592 class VarMapBuilder : public ConstStmtVisitor<VarMapBuilder> {
|
|
|
593 public:
|
|
|
594 LocalVariableMap* VMap;
|
|
|
595 LocalVariableMap::Context Ctx;
|
|
|
596
|
|
|
597 VarMapBuilder(LocalVariableMap *VM, LocalVariableMap::Context C)
|
|
|
598 : VMap(VM), Ctx(C) {}
|
|
|
599
|
|
|
600 void VisitDeclStmt(const DeclStmt *S);
|
|
|
601 void VisitBinaryOperator(const BinaryOperator *BO);
|
|
|
602 };
|
|
|
603
|
|
|
604 } // namespace
|
|
|
605
|
|
|
606 // Add new local variables to the variable map
|
|
|
607 void VarMapBuilder::VisitDeclStmt(const DeclStmt *S) {
|
|
|
608 bool modifiedCtx = false;
|
|
|
609 const DeclGroupRef DGrp = S->getDeclGroup();
|
|
|
610 for (const auto *D : DGrp) {
|
|
|
611 if (const auto *VD = dyn_cast_or_null<VarDecl>(D)) {
|
|
|
612 const Expr *E = VD->getInit();
|
|
|
613
|
|
|
614 // Add local variables with trivial type to the variable map
|
|
|
615 QualType T = VD->getType();
|
|
|
616 if (T.isTrivialType(VD->getASTContext())) {
|
|
|
617 Ctx = VMap->addDefinition(VD, E, Ctx);
|
|
|
618 modifiedCtx = true;
|
|
|
619 }
|
|
|
620 }
|
|
|
621 }
|
|
|
622 if (modifiedCtx)
|
|
|
623 VMap->saveContext(S, Ctx);
|
|
|
624 }
|
|
|
625
|
|
|
626 // Update local variable definitions in variable map
|
|
|
627 void VarMapBuilder::VisitBinaryOperator(const BinaryOperator *BO) {
|
|
|
628 if (!BO->isAssignmentOp())
|
|
|
629 return;
|
|
|
630
|
|
|
631 Expr *LHSExp = BO->getLHS()->IgnoreParenCasts();
|
|
|
632
|
|
|
633 // Update the variable map and current context.
|
|
|
634 if (const auto *DRE = dyn_cast<DeclRefExpr>(LHSExp)) {
|
|
|
635 const ValueDecl *VDec = DRE->getDecl();
|
|
|
636 if (Ctx.lookup(VDec)) {
|
|
|
637 if (BO->getOpcode() == BO_Assign)
|
|
|
638 Ctx = VMap->updateDefinition(VDec, BO->getRHS(), Ctx);
|
|
|
639 else
|
|
|
640 // FIXME -- handle compound assignment operators
|
|
|
641 Ctx = VMap->clearDefinition(VDec, Ctx);
|
|
|
642 VMap->saveContext(BO, Ctx);
|
|
|
643 }
|
|
|
644 }
|
|
|
645 }
|
|
|
646
|
|
|
647 // Computes the intersection of two contexts. The intersection is the
|
|
|
648 // set of variables which have the same definition in both contexts;
|
|
|
649 // variables with different definitions are discarded.
|
|
|
650 LocalVariableMap::Context
|
|
|
651 LocalVariableMap::intersectContexts(Context C1, Context C2) {
|
|
|
652 Context Result = C1;
|
|
|
653 for (const auto &P : C1) {
|
|
|
654 const NamedDecl *Dec = P.first;
|
|
|
655 const unsigned *i2 = C2.lookup(Dec);
|
|
|
656 if (!i2) // variable doesn't exist on second path
|
|
|
657 Result = removeDefinition(Dec, Result);
|
|
|
658 else if (*i2 != P.second) // variable exists, but has different definition
|
|
|
659 Result = clearDefinition(Dec, Result);
|
|
|
660 }
|
|
|
661 return Result;
|
|
|
662 }
|
|
|
663
|
|
|
664 // For every variable in C, create a new variable that refers to the
|
|
|
665 // definition in C. Return a new context that contains these new variables.
|
|
|
666 // (We use this for a naive implementation of SSA on loop back-edges.)
|
|
|
667 LocalVariableMap::Context LocalVariableMap::createReferenceContext(Context C) {
|
|
|
668 Context Result = getEmptyContext();
|
|
|
669 for (const auto &P : C)
|
|
|
670 Result = addReference(P.first, P.second, Result);
|
|
|
671 return Result;
|
|
|
672 }
|
|
|
673
|
|
|
674 // This routine also takes the intersection of C1 and C2, but it does so by
|
|
|
675 // altering the VarDefinitions. C1 must be the result of an earlier call to
|
|
|
676 // createReferenceContext.
|
|
|
677 void LocalVariableMap::intersectBackEdge(Context C1, Context C2) {
|
|
|
678 for (const auto &P : C1) {
|
|
|
679 unsigned i1 = P.second;
|
|
|
680 VarDefinition *VDef = &VarDefinitions[i1];
|
|
|
681 assert(VDef->isReference());
|
|
|
682
|
|
|
683 const unsigned *i2 = C2.lookup(P.first);
|
|
|
684 if (!i2 || (*i2 != i1))
|
|
|
685 VDef->Ref = 0; // Mark this variable as undefined
|
|
|
686 }
|
|
|
687 }
|
|
|
688
|
|
|
689 // Traverse the CFG in topological order, so all predecessors of a block
|
|
|
690 // (excluding back-edges) are visited before the block itself. At
|
|
|
691 // each point in the code, we calculate a Context, which holds the set of
|
|
|
692 // variable definitions which are visible at that point in execution.
|
|
|
693 // Visible variables are mapped to their definitions using an array that
|
|
|
694 // contains all definitions.
|
|
|
695 //
|
|
|
696 // At join points in the CFG, the set is computed as the intersection of
|
|
|
697 // the incoming sets along each edge, E.g.
|
|
|
698 //
|
|
|
699 // { Context | VarDefinitions }
|
|
|
700 // int x = 0; { x -> x1 | x1 = 0 }
|
|
|
701 // int y = 0; { x -> x1, y -> y1 | y1 = 0, x1 = 0 }
|
|
|
702 // if (b) x = 1; { x -> x2, y -> y1 | x2 = 1, y1 = 0, ... }
|
|
|
703 // else x = 2; { x -> x3, y -> y1 | x3 = 2, x2 = 1, ... }
|
|
|
704 // ... { y -> y1 (x is unknown) | x3 = 2, x2 = 1, ... }
|
|
|
705 //
|
|
|
706 // This is essentially a simpler and more naive version of the standard SSA
|
|
|
707 // algorithm. Those definitions that remain in the intersection are from blocks
|
|
|
708 // that strictly dominate the current block. We do not bother to insert proper
|
|
|
709 // phi nodes, because they are not used in our analysis; instead, wherever
|
|
|
710 // a phi node would be required, we simply remove that definition from the
|
|
|
711 // context (E.g. x above).
|
|
|
712 //
|
|
|
713 // The initial traversal does not capture back-edges, so those need to be
|
|
|
714 // handled on a separate pass. Whenever the first pass encounters an
|
|
|
715 // incoming back edge, it duplicates the context, creating new definitions
|
|
|
716 // that refer back to the originals. (These correspond to places where SSA
|
|
|
717 // might have to insert a phi node.) On the second pass, these definitions are
|
|
|
718 // set to NULL if the variable has changed on the back-edge (i.e. a phi
|
|
|
719 // node was actually required.) E.g.
|
|
|
720 //
|
|
|
721 // { Context | VarDefinitions }
|
|
|
722 // int x = 0, y = 0; { x -> x1, y -> y1 | y1 = 0, x1 = 0 }
|
|
|
723 // while (b) { x -> x2, y -> y1 | [1st:] x2=x1; [2nd:] x2=NULL; }
|
|
|
724 // x = x+1; { x -> x3, y -> y1 | x3 = x2 + 1, ... }
|
|
|
725 // ... { y -> y1 | x3 = 2, x2 = 1, ... }
|
|
|
726 void LocalVariableMap::traverseCFG(CFG *CFGraph,
|
|
|
727 const PostOrderCFGView *SortedGraph,
|
|
|
728 std::vector<CFGBlockInfo> &BlockInfo) {
|
|
|
729 PostOrderCFGView::CFGBlockSet VisitedBlocks(CFGraph);
|
|
|
730
|
|
|
731 CtxIndices.resize(CFGraph->getNumBlockIDs());
|
|
|
732
|
|
|
733 for (const auto *CurrBlock : *SortedGraph) {
|
|
|
734 unsigned CurrBlockID = CurrBlock->getBlockID();
|
|
|
735 CFGBlockInfo *CurrBlockInfo = &BlockInfo[CurrBlockID];
|
|
|
736
|
|
|
737 VisitedBlocks.insert(CurrBlock);
|
|
|
738
|
|
|
739 // Calculate the entry context for the current block
|
|
|
740 bool HasBackEdges = false;
|
|
|
741 bool CtxInit = true;
|
|
|
742 for (CFGBlock::const_pred_iterator PI = CurrBlock->pred_begin(),
|
|
|
743 PE = CurrBlock->pred_end(); PI != PE; ++PI) {
|
|
|
744 // if *PI -> CurrBlock is a back edge, so skip it
|
|
|
745 if (*PI == nullptr || !VisitedBlocks.alreadySet(*PI)) {
|
|
|
746 HasBackEdges = true;
|
|
|
747 continue;
|
|
|
748 }
|
|
|
749
|
|
|
750 unsigned PrevBlockID = (*PI)->getBlockID();
|
|
|
751 CFGBlockInfo *PrevBlockInfo = &BlockInfo[PrevBlockID];
|
|
|
752
|
|
|
753 if (CtxInit) {
|
|
|
754 CurrBlockInfo->EntryContext = PrevBlockInfo->ExitContext;
|
|
|
755 CtxInit = false;
|
|
|
756 }
|
|
|
757 else {
|
|
|
758 CurrBlockInfo->EntryContext =
|
|
|
759 intersectContexts(CurrBlockInfo->EntryContext,
|
|
|
760 PrevBlockInfo->ExitContext);
|
|
|
761 }
|
|
|
762 }
|
|
|
763
|
|
|
764 // Duplicate the context if we have back-edges, so we can call
|
|
|
765 // intersectBackEdges later.
|
|
|
766 if (HasBackEdges)
|
|
|
767 CurrBlockInfo->EntryContext =
|
|
|
768 createReferenceContext(CurrBlockInfo->EntryContext);
|
|
|
769
|
|
|
770 // Create a starting context index for the current block
|
|
|
771 saveContext(nullptr, CurrBlockInfo->EntryContext);
|
|
|
772 CurrBlockInfo->EntryIndex = getContextIndex();
|
|
|
773
|
|
|
774 // Visit all the statements in the basic block.
|
|
|
775 VarMapBuilder VMapBuilder(this, CurrBlockInfo->EntryContext);
|
|
|
776 for (const auto &BI : *CurrBlock) {
|
|
|
777 switch (BI.getKind()) {
|
|
|
778 case CFGElement::Statement: {
|
|
|
779 CFGStmt CS = BI.castAs<CFGStmt>();
|
|
|
780 VMapBuilder.Visit(CS.getStmt());
|
|
|
781 break;
|
|
|
782 }
|
|
|
783 default:
|
|
|
784 break;
|
|
|
785 }
|
|
|
786 }
|
|
|
787 CurrBlockInfo->ExitContext = VMapBuilder.Ctx;
|
|
|
788
|
|
|
789 // Mark variables on back edges as "unknown" if they've been changed.
|
|
|
790 for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(),
|
|
|
791 SE = CurrBlock->succ_end(); SI != SE; ++SI) {
|
|
|
792 // if CurrBlock -> *SI is *not* a back edge
|
|
|
793 if (*SI == nullptr || !VisitedBlocks.alreadySet(*SI))
|
|
|
794 continue;
|
|
|
795
|
|
|
796 CFGBlock *FirstLoopBlock = *SI;
|
|
|
797 Context LoopBegin = BlockInfo[FirstLoopBlock->getBlockID()].EntryContext;
|
|
|
798 Context LoopEnd = CurrBlockInfo->ExitContext;
|
|
|
799 intersectBackEdge(LoopBegin, LoopEnd);
|
|
|
800 }
|
|
|
801 }
|
|
|
802
|
|
|
803 // Put an extra entry at the end of the indexed context array
|
|
|
804 unsigned exitID = CFGraph->getExit().getBlockID();
|
|
|
805 saveContext(nullptr, BlockInfo[exitID].ExitContext);
|
|
|
806 }
|
|
|
807
|
|
|
808 /// Find the appropriate source locations to use when producing diagnostics for
|
|
|
809 /// each block in the CFG.
|
|
|
810 static void findBlockLocations(CFG *CFGraph,
|
|
|
811 const PostOrderCFGView *SortedGraph,
|
|
|
812 std::vector<CFGBlockInfo> &BlockInfo) {
|
|
|
813 for (const auto *CurrBlock : *SortedGraph) {
|
|
|
814 CFGBlockInfo *CurrBlockInfo = &BlockInfo[CurrBlock->getBlockID()];
|
|
|
815
|
|
|
816 // Find the source location of the last statement in the block, if the
|
|
|
817 // block is not empty.
|
|
|
818 if (const Stmt *S = CurrBlock->getTerminatorStmt()) {
|
|
|
819 CurrBlockInfo->EntryLoc = CurrBlockInfo->ExitLoc = S->getBeginLoc();
|
|
|
820 } else {
|
|
|
821 for (CFGBlock::const_reverse_iterator BI = CurrBlock->rbegin(),
|
|
|
822 BE = CurrBlock->rend(); BI != BE; ++BI) {
|
|
|
823 // FIXME: Handle other CFGElement kinds.
|
|
|
824 if (Optional<CFGStmt> CS = BI->getAs<CFGStmt>()) {
|
|
|
825 CurrBlockInfo->ExitLoc = CS->getStmt()->getBeginLoc();
|
|
|
826 break;
|
|
|
827 }
|
|
|
828 }
|
|
|
829 }
|
|
|
830
|
|
|
831 if (CurrBlockInfo->ExitLoc.isValid()) {
|
|
|
832 // This block contains at least one statement. Find the source location
|
|
|
833 // of the first statement in the block.
|
|
|
834 for (const auto &BI : *CurrBlock) {
|
|
|
835 // FIXME: Handle other CFGElement kinds.
|
|
|
836 if (Optional<CFGStmt> CS = BI.getAs<CFGStmt>()) {
|
|
|
837 CurrBlockInfo->EntryLoc = CS->getStmt()->getBeginLoc();
|
|
|
838 break;
|
|
|
839 }
|
|
|
840 }
|
|
|
841 } else if (CurrBlock->pred_size() == 1 && *CurrBlock->pred_begin() &&
|
|
|
842 CurrBlock != &CFGraph->getExit()) {
|
|
|
843 // The block is empty, and has a single predecessor. Use its exit
|
|
|
844 // location.
|
|
|
845 CurrBlockInfo->EntryLoc = CurrBlockInfo->ExitLoc =
|
|
|
846 BlockInfo[(*CurrBlock->pred_begin())->getBlockID()].ExitLoc;
|
|
|
847 }
|
|
|
848 }
|
|
|
849 }
|
|
|
850
|
|
|
851 namespace {
|
|
|
852
|
|
|
853 class LockableFactEntry : public FactEntry {
|
|
|
854 private:
|
|
|
855 /// managed by ScopedLockable object
|
|
|
856 bool Managed;
|
|
|
857
|
|
|
858 public:
|
|
|
859 LockableFactEntry(const CapabilityExpr &CE, LockKind LK, SourceLocation Loc,
|
|
|
860 bool Mng = false, bool Asrt = false)
|
|
|
861 : FactEntry(CE, LK, Loc, Asrt), Managed(Mng) {}
|
|
|
862
|
|
|
863 void
|
|
|
864 handleRemovalFromIntersection(const FactSet &FSet, FactManager &FactMan,
|
|
|
865 SourceLocation JoinLoc, LockErrorKind LEK,
|
|
|
866 ThreadSafetyHandler &Handler) const override {
|
|
|
867 if (!Managed && !asserted() && !negative() && !isUniversal()) {
|
|
|
868 Handler.handleMutexHeldEndOfScope("mutex", toString(), loc(), JoinLoc,
|
|
|
869 LEK);
|
|
|
870 }
|
|
|
871 }
|
|
|
872
|
|
|
873 void handleLock(FactSet &FSet, FactManager &FactMan, const FactEntry &entry,
|
|
|
874 ThreadSafetyHandler &Handler,
|
|
|
875 StringRef DiagKind) const override {
|
|
|
876 Handler.handleDoubleLock(DiagKind, entry.toString(), loc(), entry.loc());
|
|
|
877 }
|
|
|
878
|
|
|
879 void handleUnlock(FactSet &FSet, FactManager &FactMan,
|
|
|
880 const CapabilityExpr &Cp, SourceLocation UnlockLoc,
|
|
|
881 bool FullyRemove, ThreadSafetyHandler &Handler,
|
|
|
882 StringRef DiagKind) const override {
|
|
|
883 FSet.removeLock(FactMan, Cp);
|
|
|
884 if (!Cp.negative()) {
|
|
|
885 FSet.addLock(FactMan, std::make_unique<LockableFactEntry>(
|
|
|
886 !Cp, LK_Exclusive, UnlockLoc));
|
|
|
887 }
|
|
|
888 }
|
|
|
889 };
|
|
|
890
|
|
|
891 class ScopedLockableFactEntry : public FactEntry {
|
|
|
892 private:
|
|
|
893 enum UnderlyingCapabilityKind {
|
|
|
894 UCK_Acquired, ///< Any kind of acquired capability.
|
|
|
895 UCK_ReleasedShared, ///< Shared capability that was released.
|
|
|
896 UCK_ReleasedExclusive, ///< Exclusive capability that was released.
|
|
|
897 };
|
|
|
898
|
|
|
899 using UnderlyingCapability =
|
|
|
900 llvm::PointerIntPair<const til::SExpr *, 2, UnderlyingCapabilityKind>;
|
|
|
901
|
|
|
902 SmallVector<UnderlyingCapability, 4> UnderlyingMutexes;
|
|
|
903
|
|
|
904 public:
|
|
|
905 ScopedLockableFactEntry(const CapabilityExpr &CE, SourceLocation Loc)
|
|
|
906 : FactEntry(CE, LK_Exclusive, Loc, false) {}
|
|
|
907
|
|
|
908 void addExclusiveLock(const CapabilityExpr &M) {
|
|
|
909 UnderlyingMutexes.emplace_back(M.sexpr(), UCK_Acquired);
|
|
|
910 }
|
|
|
911
|
|
|
912 void addSharedLock(const CapabilityExpr &M) {
|
|
|
913 UnderlyingMutexes.emplace_back(M.sexpr(), UCK_Acquired);
|
|
|
914 }
|
|
|
915
|
|
|
916 void addExclusiveUnlock(const CapabilityExpr &M) {
|
|
|
917 UnderlyingMutexes.emplace_back(M.sexpr(), UCK_ReleasedExclusive);
|
|
|
918 }
|
|
|
919
|
|
|
920 void addSharedUnlock(const CapabilityExpr &M) {
|
|
|
921 UnderlyingMutexes.emplace_back(M.sexpr(), UCK_ReleasedShared);
|
|
|
922 }
|
|
|
923
|
|
|
924 void
|
|
|
925 handleRemovalFromIntersection(const FactSet &FSet, FactManager &FactMan,
|
|
|
926 SourceLocation JoinLoc, LockErrorKind LEK,
|
|
|
927 ThreadSafetyHandler &Handler) const override {
|
|
|
928 for (const auto &UnderlyingMutex : UnderlyingMutexes) {
|
|
|
929 const auto *Entry = FSet.findLock(
|
|
|
930 FactMan, CapabilityExpr(UnderlyingMutex.getPointer(), false));
|
|
|
931 if ((UnderlyingMutex.getInt() == UCK_Acquired && Entry) ||
|
|
|
932 (UnderlyingMutex.getInt() != UCK_Acquired && !Entry)) {
|
|
|
933 // If this scoped lock manages another mutex, and if the underlying
|
|
|
934 // mutex is still/not held, then warn about the underlying mutex.
|
|
|
935 Handler.handleMutexHeldEndOfScope(
|
|
|
936 "mutex", sx::toString(UnderlyingMutex.getPointer()), loc(), JoinLoc,
|
|
|
937 LEK);
|
|
|
938 }
|
|
|
939 }
|
|
|
940 }
|
|
|
941
|
|
|
942 void handleLock(FactSet &FSet, FactManager &FactMan, const FactEntry &entry,
|
|
|
943 ThreadSafetyHandler &Handler,
|
|
|
944 StringRef DiagKind) const override {
|
|
|
945 for (const auto &UnderlyingMutex : UnderlyingMutexes) {
|
|
|
946 CapabilityExpr UnderCp(UnderlyingMutex.getPointer(), false);
|
|
|
947
|
|
|
948 if (UnderlyingMutex.getInt() == UCK_Acquired)
|
|
|
949 lock(FSet, FactMan, UnderCp, entry.kind(), entry.loc(), &Handler,
|
|
|
950 DiagKind);
|
|
|
951 else
|
|
|
952 unlock(FSet, FactMan, UnderCp, entry.loc(), &Handler, DiagKind);
|
|
|
953 }
|
|
|
954 }
|
|
|
955
|
|
|
956 void handleUnlock(FactSet &FSet, FactManager &FactMan,
|
|
|
957 const CapabilityExpr &Cp, SourceLocation UnlockLoc,
|
|
|
958 bool FullyRemove, ThreadSafetyHandler &Handler,
|
|
|
959 StringRef DiagKind) const override {
|
|
|
960 assert(!Cp.negative() && "Managing object cannot be negative.");
|
|
|
961 for (const auto &UnderlyingMutex : UnderlyingMutexes) {
|
|
|
962 CapabilityExpr UnderCp(UnderlyingMutex.getPointer(), false);
|
|
|
963
|
|
|
964 // Remove/lock the underlying mutex if it exists/is still unlocked; warn
|
|
|
965 // on double unlocking/locking if we're not destroying the scoped object.
|
|
|
966 ThreadSafetyHandler *TSHandler = FullyRemove ? nullptr : &Handler;
|
|
|
967 if (UnderlyingMutex.getInt() == UCK_Acquired) {
|
|
|
968 unlock(FSet, FactMan, UnderCp, UnlockLoc, TSHandler, DiagKind);
|
|
|
969 } else {
|
|
|
970 LockKind kind = UnderlyingMutex.getInt() == UCK_ReleasedShared
|
|
|
971 ? LK_Shared
|
|
|
972 : LK_Exclusive;
|
|
|
973 lock(FSet, FactMan, UnderCp, kind, UnlockLoc, TSHandler, DiagKind);
|
|
|
974 }
|
|
|
975 }
|
|
|
976 if (FullyRemove)
|
|
|
977 FSet.removeLock(FactMan, Cp);
|
|
|
978 }
|
|
|
979
|
|
|
980 private:
|
|
|
981 void lock(FactSet &FSet, FactManager &FactMan, const CapabilityExpr &Cp,
|
|
|
982 LockKind kind, SourceLocation loc, ThreadSafetyHandler *Handler,
|
|
|
983 StringRef DiagKind) const {
|
|
|
984 if (const FactEntry *Fact = FSet.findLock(FactMan, Cp)) {
|
|
|
985 if (Handler)
|
|
|
986 Handler->handleDoubleLock(DiagKind, Cp.toString(), Fact->loc(), loc);
|
|
|
987 } else {
|
|
|
988 FSet.removeLock(FactMan, !Cp);
|
|
|
989 FSet.addLock(FactMan,
|
|
|
990 std::make_unique<LockableFactEntry>(Cp, kind, loc));
|
|
|
991 }
|
|
|
992 }
|
|
|
993
|
|
|
994 void unlock(FactSet &FSet, FactManager &FactMan, const CapabilityExpr &Cp,
|
|
|
995 SourceLocation loc, ThreadSafetyHandler *Handler,
|
|
|
996 StringRef DiagKind) const {
|
|
|
997 if (FSet.findLock(FactMan, Cp)) {
|
|
|
998 FSet.removeLock(FactMan, Cp);
|
|
|
999 FSet.addLock(FactMan, std::make_unique<LockableFactEntry>(
|
|
|
1000 !Cp, LK_Exclusive, loc));
|
|
|
1001 } else if (Handler) {
|
|
|
1002 Handler->handleUnmatchedUnlock(DiagKind, Cp.toString(), loc);
|
|
|
1003 }
|
|
|
1004 }
|
|
|
1005 };
|
|
|
1006
|
|
|
1007 /// Class which implements the core thread safety analysis routines.
|
|
|
1008 class ThreadSafetyAnalyzer {
|
|
|
1009 friend class BuildLockset;
|
|
|
1010 friend class threadSafety::BeforeSet;
|
|
|
1011
|
|
|
1012 llvm::BumpPtrAllocator Bpa;
|
|
|
1013 threadSafety::til::MemRegionRef Arena;
|
|
|
1014 threadSafety::SExprBuilder SxBuilder;
|
|
|
1015
|
|
|
1016 ThreadSafetyHandler &Handler;
|
|
|
1017 const CXXMethodDecl *CurrentMethod;
|
|
|
1018 LocalVariableMap LocalVarMap;
|
|
|
1019 FactManager FactMan;
|
|
|
1020 std::vector<CFGBlockInfo> BlockInfo;
|
|
|
1021
|
|
|
1022 BeforeSet *GlobalBeforeSet;
|
|
|
1023
|
|
|
1024 public:
|
|
|
1025 ThreadSafetyAnalyzer(ThreadSafetyHandler &H, BeforeSet* Bset)
|
|
|
1026 : Arena(&Bpa), SxBuilder(Arena), Handler(H), GlobalBeforeSet(Bset) {}
|
|
|
1027
|
|
|
1028 bool inCurrentScope(const CapabilityExpr &CapE);
|
|
|
1029
|
|
|
1030 void addLock(FactSet &FSet, std::unique_ptr<FactEntry> Entry,
|
|
|
1031 StringRef DiagKind, bool ReqAttr = false);
|
|
|
1032 void removeLock(FactSet &FSet, const CapabilityExpr &CapE,
|
|
|
1033 SourceLocation UnlockLoc, bool FullyRemove, LockKind Kind,
|
|
|
1034 StringRef DiagKind);
|
|
|
1035
|
|
|
1036 template <typename AttrType>
|
|
|
1037 void getMutexIDs(CapExprSet &Mtxs, AttrType *Attr, const Expr *Exp,
|
|
|
1038 const NamedDecl *D, VarDecl *SelfDecl = nullptr);
|
|
|
1039
|
|
|
1040 template <class AttrType>
|
|
|
1041 void getMutexIDs(CapExprSet &Mtxs, AttrType *Attr, const Expr *Exp,
|
|
|
1042 const NamedDecl *D,
|
|
|
1043 const CFGBlock *PredBlock, const CFGBlock *CurrBlock,
|
|
|
1044 Expr *BrE, bool Neg);
|
|
|
1045
|
|
|
1046 const CallExpr* getTrylockCallExpr(const Stmt *Cond, LocalVarContext C,
|
|
|
1047 bool &Negate);
|
|
|
1048
|
|
|
1049 void getEdgeLockset(FactSet &Result, const FactSet &ExitSet,
|
|
|
1050 const CFGBlock* PredBlock,
|
|
|
1051 const CFGBlock *CurrBlock);
|
|
|
1052
|
|
|
1053 void intersectAndWarn(FactSet &FSet1, const FactSet &FSet2,
|
|
|
1054 SourceLocation JoinLoc,
|
|
|
1055 LockErrorKind LEK1, LockErrorKind LEK2,
|
|
|
1056 bool Modify=true);
|
|
|
1057
|
|
|
1058 void intersectAndWarn(FactSet &FSet1, const FactSet &FSet2,
|
|
|
1059 SourceLocation JoinLoc, LockErrorKind LEK1,
|
|
|
1060 bool Modify=true) {
|
|
|
1061 intersectAndWarn(FSet1, FSet2, JoinLoc, LEK1, LEK1, Modify);
|
|
|
1062 }
|
|
|
1063
|
|
|
1064 void runAnalysis(AnalysisDeclContext &AC);
|
|
|
1065 };
|
|
|
1066
|
|
|
1067 } // namespace
|
|
|
1068
|
|
|
1069 /// Process acquired_before and acquired_after attributes on Vd.
|
|
|
1070 BeforeSet::BeforeInfo* BeforeSet::insertAttrExprs(const ValueDecl* Vd,
|
|
|
1071 ThreadSafetyAnalyzer& Analyzer) {
|
|
|
1072 // Create a new entry for Vd.
|
|
|
1073 BeforeInfo *Info = nullptr;
|
|
|
1074 {
|
|
|
1075 // Keep InfoPtr in its own scope in case BMap is modified later and the
|
|
|
1076 // reference becomes invalid.
|
|
|
1077 std::unique_ptr<BeforeInfo> &InfoPtr = BMap[Vd];
|
|
|
1078 if (!InfoPtr)
|
|
|
1079 InfoPtr.reset(new BeforeInfo());
|
|
|
1080 Info = InfoPtr.get();
|
|
|
1081 }
|
|
|
1082
|
|
|
1083 for (const auto *At : Vd->attrs()) {
|
|
|
1084 switch (At->getKind()) {
|
|
|
1085 case attr::AcquiredBefore: {
|
|
|
1086 const auto *A = cast<AcquiredBeforeAttr>(At);
|
|
|
1087
|
|
|
1088 // Read exprs from the attribute, and add them to BeforeVect.
|
|
|
1089 for (const auto *Arg : A->args()) {
|
|
|
1090 CapabilityExpr Cp =
|
|
|
1091 Analyzer.SxBuilder.translateAttrExpr(Arg, nullptr);
|
|
|
1092 if (const ValueDecl *Cpvd = Cp.valueDecl()) {
|
|
|
1093 Info->Vect.push_back(Cpvd);
|
|
|
1094 const auto It = BMap.find(Cpvd);
|
|
|
1095 if (It == BMap.end())
|
|
|
1096 insertAttrExprs(Cpvd, Analyzer);
|
|
|
1097 }
|
|
|
1098 }
|
|
|
1099 break;
|
|
|
1100 }
|
|
|
1101 case attr::AcquiredAfter: {
|
|
|
1102 const auto *A = cast<AcquiredAfterAttr>(At);
|
|
|
1103
|
|
|
1104 // Read exprs from the attribute, and add them to BeforeVect.
|
|
|
1105 for (const auto *Arg : A->args()) {
|
|
|
1106 CapabilityExpr Cp =
|
|
|
1107 Analyzer.SxBuilder.translateAttrExpr(Arg, nullptr);
|
|
|
1108 if (const ValueDecl *ArgVd = Cp.valueDecl()) {
|
|
|
1109 // Get entry for mutex listed in attribute
|
|
|
1110 BeforeInfo *ArgInfo = getBeforeInfoForDecl(ArgVd, Analyzer);
|
|
|
1111 ArgInfo->Vect.push_back(Vd);
|
|
|
1112 }
|
|
|
1113 }
|
|
|
1114 break;
|
|
|
1115 }
|
|
|
1116 default:
|
|
|
1117 break;
|
|
|
1118 }
|
|
|
1119 }
|
|
|
1120
|
|
|
1121 return Info;
|
|
|
1122 }
|
|
|
1123
|
|
|
1124 BeforeSet::BeforeInfo *
|
|
|
1125 BeforeSet::getBeforeInfoForDecl(const ValueDecl *Vd,
|
|
|
1126 ThreadSafetyAnalyzer &Analyzer) {
|
|
|
1127 auto It = BMap.find(Vd);
|
|
|
1128 BeforeInfo *Info = nullptr;
|
|
|
1129 if (It == BMap.end())
|
|
|
1130 Info = insertAttrExprs(Vd, Analyzer);
|
|
|
1131 else
|
|
|
1132 Info = It->second.get();
|
|
|
1133 assert(Info && "BMap contained nullptr?");
|
|
|
1134 return Info;
|
|
|
1135 }
|
|
|
1136
|
|
|
1137 /// Return true if any mutexes in FSet are in the acquired_before set of Vd.
|
|
|
1138 void BeforeSet::checkBeforeAfter(const ValueDecl* StartVd,
|
|
|
1139 const FactSet& FSet,
|
|
|
1140 ThreadSafetyAnalyzer& Analyzer,
|
|
|
1141 SourceLocation Loc, StringRef CapKind) {
|
|
|
1142 SmallVector<BeforeInfo*, 8> InfoVect;
|
|
|
1143
|
|
|
1144 // Do a depth-first traversal of Vd.
|
|
|
1145 // Return true if there are cycles.
|
|
|
1146 std::function<bool (const ValueDecl*)> traverse = [&](const ValueDecl* Vd) {
|
|
|
1147 if (!Vd)
|
|
|
1148 return false;
|
|
|
1149
|
|
|
1150 BeforeSet::BeforeInfo *Info = getBeforeInfoForDecl(Vd, Analyzer);
|
|
|
1151
|
|
|
1152 if (Info->Visited == 1)
|
|
|
1153 return true;
|
|
|
1154
|
|
|
1155 if (Info->Visited == 2)
|
|
|
1156 return false;
|
|
|
1157
|
|
|
1158 if (Info->Vect.empty())
|
|
|
1159 return false;
|
|
|
1160
|
|
|
1161 InfoVect.push_back(Info);
|
|
|
1162 Info->Visited = 1;
|
|
|
1163 for (const auto *Vdb : Info->Vect) {
|
|
|
1164 // Exclude mutexes in our immediate before set.
|
|
|
1165 if (FSet.containsMutexDecl(Analyzer.FactMan, Vdb)) {
|
|
|
1166 StringRef L1 = StartVd->getName();
|
|
|
1167 StringRef L2 = Vdb->getName();
|
|
|
1168 Analyzer.Handler.handleLockAcquiredBefore(CapKind, L1, L2, Loc);
|
|
|
1169 }
|
|
|
1170 // Transitively search other before sets, and warn on cycles.
|
|
|
1171 if (traverse(Vdb)) {
|
|
|
1172 if (CycMap.find(Vd) == CycMap.end()) {
|
|
|
1173 CycMap.insert(std::make_pair(Vd, true));
|
|
|
1174 StringRef L1 = Vd->getName();
|
|
|
1175 Analyzer.Handler.handleBeforeAfterCycle(L1, Vd->getLocation());
|
|
|
1176 }
|
|
|
1177 }
|
|
|
1178 }
|
|
|
1179 Info->Visited = 2;
|
|
|
1180 return false;
|
|
|
1181 };
|
|
|
1182
|
|
|
1183 traverse(StartVd);
|
|
|
1184
|
|
|
1185 for (auto *Info : InfoVect)
|
|
|
1186 Info->Visited = 0;
|
|
|
1187 }
|
|
|
1188
|
|
|
1189 /// Gets the value decl pointer from DeclRefExprs or MemberExprs.
|
|
|
1190 static const ValueDecl *getValueDecl(const Expr *Exp) {
|
|
|
1191 if (const auto *CE = dyn_cast<ImplicitCastExpr>(Exp))
|
|
|
1192 return getValueDecl(CE->getSubExpr());
|
|
|
1193
|
|
|
1194 if (const auto *DR = dyn_cast<DeclRefExpr>(Exp))
|
|
|
1195 return DR->getDecl();
|
|
|
1196
|
|
|
1197 if (const auto *ME = dyn_cast<MemberExpr>(Exp))
|
|
|
1198 return ME->getMemberDecl();
|
|
|
1199
|
|
|
1200 return nullptr;
|
|
|
1201 }
|
|
|
1202
|
|
|
1203 namespace {
|
|
|
1204
|
|
|
1205 template <typename Ty>
|
|
|
1206 class has_arg_iterator_range {
|
|
|
1207 using yes = char[1];
|
|
|
1208 using no = char[2];
|
|
|
1209
|
|
|
1210 template <typename Inner>
|
|
|
1211 static yes& test(Inner *I, decltype(I->args()) * = nullptr);
|
|
|
1212
|
|
|
1213 template <typename>
|
|
|
1214 static no& test(...);
|
|
|
1215
|
|
|
1216 public:
|
|
|
1217 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
|
|
|
1218 };
|
|
|
1219
|
|
|
1220 } // namespace
|
|
|
1221
|
|
|
1222 static StringRef ClassifyDiagnostic(const CapabilityAttr *A) {
|
|
|
1223 return A->getName();
|
|
|
1224 }
|
|
|
1225
|
|
|
1226 static StringRef ClassifyDiagnostic(QualType VDT) {
|
|
|
1227 // We need to look at the declaration of the type of the value to determine
|
|
|
1228 // which it is. The type should either be a record or a typedef, or a pointer
|
|
|
1229 // or reference thereof.
|
|
|
1230 if (const auto *RT = VDT->getAs<RecordType>()) {
|
|
|
1231 if (const auto *RD = RT->getDecl())
|
|
|
1232 if (const auto *CA = RD->getAttr<CapabilityAttr>())
|
|
|
1233 return ClassifyDiagnostic(CA);
|
|
|
1234 } else if (const auto *TT = VDT->getAs<TypedefType>()) {
|
|
|
1235 if (const auto *TD = TT->getDecl())
|
|
|
1236 if (const auto *CA = TD->getAttr<CapabilityAttr>())
|
|
|
1237 return ClassifyDiagnostic(CA);
|
|
|
1238 } else if (VDT->isPointerType() || VDT->isReferenceType())
|
|
|
1239 return ClassifyDiagnostic(VDT->getPointeeType());
|
|
|
1240
|
|
|
1241 return "mutex";
|
|
|
1242 }
|
|
|
1243
|
|
|
1244 static StringRef ClassifyDiagnostic(const ValueDecl *VD) {
|
|
|
1245 assert(VD && "No ValueDecl passed");
|
|
|
1246
|
|
|
1247 // The ValueDecl is the declaration of a mutex or role (hopefully).
|
|
|
1248 return ClassifyDiagnostic(VD->getType());
|
|
|
1249 }
|
|
|
1250
|
|
|
1251 template <typename AttrTy>
|
|
|
1252 static std::enable_if_t<!has_arg_iterator_range<AttrTy>::value, StringRef>
|
|
|
1253 ClassifyDiagnostic(const AttrTy *A) {
|
|
|
1254 if (const ValueDecl *VD = getValueDecl(A->getArg()))
|
|
|
1255 return ClassifyDiagnostic(VD);
|
|
|
1256 return "mutex";
|
|
|
1257 }
|
|
|
1258
|
|
|
1259 template <typename AttrTy>
|
|
|
1260 static std::enable_if_t<has_arg_iterator_range<AttrTy>::value, StringRef>
|
|
|
1261 ClassifyDiagnostic(const AttrTy *A) {
|
|
|
1262 for (const auto *Arg : A->args()) {
|
|
|
1263 if (const ValueDecl *VD = getValueDecl(Arg))
|
|
|
1264 return ClassifyDiagnostic(VD);
|
|
|
1265 }
|
|
|
1266 return "mutex";
|
|
|
1267 }
|
|
|
1268
|
|
|
1269 bool ThreadSafetyAnalyzer::inCurrentScope(const CapabilityExpr &CapE) {
|
|
|
1270 if (!CurrentMethod)
|
|
|
1271 return false;
|
|
|
1272 if (const auto *P = dyn_cast_or_null<til::Project>(CapE.sexpr())) {
|
|
|
1273 const auto *VD = P->clangDecl();
|
|
|
1274 if (VD)
|
|
|
1275 return VD->getDeclContext() == CurrentMethod->getDeclContext();
|
|
|
1276 }
|
|
|
1277 return false;
|
|
|
1278 }
|
|
|
1279
|
|
|
1280 /// Add a new lock to the lockset, warning if the lock is already there.
|
|
|
1281 /// \param ReqAttr -- true if this is part of an initial Requires attribute.
|
|
|
1282 void ThreadSafetyAnalyzer::addLock(FactSet &FSet,
|
|
|
1283 std::unique_ptr<FactEntry> Entry,
|
|
|
1284 StringRef DiagKind, bool ReqAttr) {
|
|
|
1285 if (Entry->shouldIgnore())
|
|
|
1286 return;
|
|
|
1287
|
|
|
1288 if (!ReqAttr && !Entry->negative()) {
|
|
|
1289 // look for the negative capability, and remove it from the fact set.
|
|
|
1290 CapabilityExpr NegC = !*Entry;
|
|
|
1291 const FactEntry *Nen = FSet.findLock(FactMan, NegC);
|
|
|
1292 if (Nen) {
|
|
|
1293 FSet.removeLock(FactMan, NegC);
|
|
|
1294 }
|
|
|
1295 else {
|
|
|
1296 if (inCurrentScope(*Entry) && !Entry->asserted())
|
|
|
1297 Handler.handleNegativeNotHeld(DiagKind, Entry->toString(),
|
|
|
1298 NegC.toString(), Entry->loc());
|
|
|
1299 }
|
|
|
1300 }
|
|
|
1301
|
|
|
1302 // Check before/after constraints
|
|
|
1303 if (Handler.issueBetaWarnings() &&
|
|
|
1304 !Entry->asserted() && !Entry->declared()) {
|
|
|
1305 GlobalBeforeSet->checkBeforeAfter(Entry->valueDecl(), FSet, *this,
|
|
|
1306 Entry->loc(), DiagKind);
|
|
|
1307 }
|
|
|
1308
|
|
|
1309 // FIXME: Don't always warn when we have support for reentrant locks.
|
|
|
1310 if (const FactEntry *Cp = FSet.findLock(FactMan, *Entry)) {
|
|
|
1311 if (!Entry->asserted())
|
|
|
1312 Cp->handleLock(FSet, FactMan, *Entry, Handler, DiagKind);
|
|
|
1313 } else {
|
|
|
1314 FSet.addLock(FactMan, std::move(Entry));
|
|
|
1315 }
|
|
|
1316 }
|
|
|
1317
|
|
|
1318 /// Remove a lock from the lockset, warning if the lock is not there.
|
|
|
1319 /// \param UnlockLoc The source location of the unlock (only used in error msg)
|
|
|
1320 void ThreadSafetyAnalyzer::removeLock(FactSet &FSet, const CapabilityExpr &Cp,
|
|
|
1321 SourceLocation UnlockLoc,
|
|
|
1322 bool FullyRemove, LockKind ReceivedKind,
|
|
|
1323 StringRef DiagKind) {
|
|
|
1324 if (Cp.shouldIgnore())
|
|
|
1325 return;
|
|
|
1326
|
|
|
1327 const FactEntry *LDat = FSet.findLock(FactMan, Cp);
|
|
|
1328 if (!LDat) {
|
|
|
1329 Handler.handleUnmatchedUnlock(DiagKind, Cp.toString(), UnlockLoc);
|
|
|
1330 return;
|
|
|
1331 }
|
|
|
1332
|
|
|
1333 // Generic lock removal doesn't care about lock kind mismatches, but
|
|
|
1334 // otherwise diagnose when the lock kinds are mismatched.
|
|
|
1335 if (ReceivedKind != LK_Generic && LDat->kind() != ReceivedKind) {
|
|
|
1336 Handler.handleIncorrectUnlockKind(DiagKind, Cp.toString(), LDat->kind(),
|
|
|
1337 ReceivedKind, LDat->loc(), UnlockLoc);
|
|
|
1338 }
|
|
|
1339
|
|
|
1340 LDat->handleUnlock(FSet, FactMan, Cp, UnlockLoc, FullyRemove, Handler,
|
|
|
1341 DiagKind);
|
|
|
1342 }
|
|
|
1343
|
|
|
1344 /// Extract the list of mutexIDs from the attribute on an expression,
|
|
|
1345 /// and push them onto Mtxs, discarding any duplicates.
|
|
|
1346 template <typename AttrType>
|
|
|
1347 void ThreadSafetyAnalyzer::getMutexIDs(CapExprSet &Mtxs, AttrType *Attr,
|
|
|
1348 const Expr *Exp, const NamedDecl *D,
|
|
|
1349 VarDecl *SelfDecl) {
|
|
|
1350 if (Attr->args_size() == 0) {
|
|
|
1351 // The mutex held is the "this" object.
|
|
|
1352 CapabilityExpr Cp = SxBuilder.translateAttrExpr(nullptr, D, Exp, SelfDecl);
|
|
|
1353 if (Cp.isInvalid()) {
|
|
|
1354 warnInvalidLock(Handler, nullptr, D, Exp, ClassifyDiagnostic(Attr));
|
|
|
1355 return;
|
|
|
1356 }
|
|
|
1357 //else
|
|
|
1358 if (!Cp.shouldIgnore())
|
|
|
1359 Mtxs.push_back_nodup(Cp);
|
|
|
1360 return;
|
|
|
1361 }
|
|
|
1362
|
|
|
1363 for (const auto *Arg : Attr->args()) {
|
|
|
1364 CapabilityExpr Cp = SxBuilder.translateAttrExpr(Arg, D, Exp, SelfDecl);
|
|
|
1365 if (Cp.isInvalid()) {
|
|
|
1366 warnInvalidLock(Handler, nullptr, D, Exp, ClassifyDiagnostic(Attr));
|
|
|
1367 continue;
|
|
|
1368 }
|
|
|
1369 //else
|
|
|
1370 if (!Cp.shouldIgnore())
|
|
|
1371 Mtxs.push_back_nodup(Cp);
|
|
|
1372 }
|
|
|
1373 }
|
|
|
1374
|
|
|
1375 /// Extract the list of mutexIDs from a trylock attribute. If the
|
|
|
1376 /// trylock applies to the given edge, then push them onto Mtxs, discarding
|
|
|
1377 /// any duplicates.
|
|
|
1378 template <class AttrType>
|
|
|
1379 void ThreadSafetyAnalyzer::getMutexIDs(CapExprSet &Mtxs, AttrType *Attr,
|
|
|
1380 const Expr *Exp, const NamedDecl *D,
|
|
|
1381 const CFGBlock *PredBlock,
|
|
|
1382 const CFGBlock *CurrBlock,
|
|
|
1383 Expr *BrE, bool Neg) {
|
|
|
1384 // Find out which branch has the lock
|
|
|
1385 bool branch = false;
|
|
|
1386 if (const auto *BLE = dyn_cast_or_null<CXXBoolLiteralExpr>(BrE))
|
|
|
1387 branch = BLE->getValue();
|
|
|
1388 else if (const auto *ILE = dyn_cast_or_null<IntegerLiteral>(BrE))
|
|
|
1389 branch = ILE->getValue().getBoolValue();
|
|
|
1390
|
|
|
1391 int branchnum = branch ? 0 : 1;
|
|
|
1392 if (Neg)
|
|
|
1393 branchnum = !branchnum;
|
|
|
1394
|
|
|
1395 // If we've taken the trylock branch, then add the lock
|
|
|
1396 int i = 0;
|
|
|
1397 for (CFGBlock::const_succ_iterator SI = PredBlock->succ_begin(),
|
|
|
1398 SE = PredBlock->succ_end(); SI != SE && i < 2; ++SI, ++i) {
|
|
|
1399 if (*SI == CurrBlock && i == branchnum)
|
|
|
1400 getMutexIDs(Mtxs, Attr, Exp, D);
|
|
|
1401 }
|
|
|
1402 }
|
|
|
1403
|
|
|
1404 static bool getStaticBooleanValue(Expr *E, bool &TCond) {
|
|
|
1405 if (isa<CXXNullPtrLiteralExpr>(E) || isa<GNUNullExpr>(E)) {
|
|
|
1406 TCond = false;
|
|
|
1407 return true;
|
|
|
1408 } else if (const auto *BLE = dyn_cast<CXXBoolLiteralExpr>(E)) {
|
|
|
1409 TCond = BLE->getValue();
|
|
|
1410 return true;
|
|
|
1411 } else if (const auto *ILE = dyn_cast<IntegerLiteral>(E)) {
|
|
|
1412 TCond = ILE->getValue().getBoolValue();
|
|
|
1413 return true;
|
|
|
1414 } else if (auto *CE = dyn_cast<ImplicitCastExpr>(E))
|
|
|
1415 return getStaticBooleanValue(CE->getSubExpr(), TCond);
|
|
|
1416 return false;
|
|
|
1417 }
|
|
|
1418
|
|
|
1419 // If Cond can be traced back to a function call, return the call expression.
|
|
|
1420 // The negate variable should be called with false, and will be set to true
|
|
|
1421 // if the function call is negated, e.g. if (!mu.tryLock(...))
|
|
|
1422 const CallExpr* ThreadSafetyAnalyzer::getTrylockCallExpr(const Stmt *Cond,
|
|
|
1423 LocalVarContext C,
|
|
|
1424 bool &Negate) {
|
|
|
1425 if (!Cond)
|
|
|
1426 return nullptr;
|
|
|
1427
|
|
|
1428 if (const auto *CallExp = dyn_cast<CallExpr>(Cond)) {
|
|
|
1429 if (CallExp->getBuiltinCallee() == Builtin::BI__builtin_expect)
|
|
|
1430 return getTrylockCallExpr(CallExp->getArg(0), C, Negate);
|
|
|
1431 return CallExp;
|
|
|
1432 }
|
|
|
1433 else if (const auto *PE = dyn_cast<ParenExpr>(Cond))
|
|
|
1434 return getTrylockCallExpr(PE->getSubExpr(), C, Negate);
|
|
|
1435 else if (const auto *CE = dyn_cast<ImplicitCastExpr>(Cond))
|
|
|
1436 return getTrylockCallExpr(CE->getSubExpr(), C, Negate);
|
|
|
1437 else if (const auto *FE = dyn_cast<FullExpr>(Cond))
|
|
|
1438 return getTrylockCallExpr(FE->getSubExpr(), C, Negate);
|
|
|
1439 else if (const auto *DRE = dyn_cast<DeclRefExpr>(Cond)) {
|
|
|
1440 const Expr *E = LocalVarMap.lookupExpr(DRE->getDecl(), C);
|
|
|
1441 return getTrylockCallExpr(E, C, Negate);
|
|
|
1442 }
|
|
|
1443 else if (const auto *UOP = dyn_cast<UnaryOperator>(Cond)) {
|
|
|
1444 if (UOP->getOpcode() == UO_LNot) {
|
|
|
1445 Negate = !Negate;
|
|
|
1446 return getTrylockCallExpr(UOP->getSubExpr(), C, Negate);
|
|
|
1447 }
|
|
|
1448 return nullptr;
|
|
|
1449 }
|
|
|
1450 else if (const auto *BOP = dyn_cast<BinaryOperator>(Cond)) {
|
|
|
1451 if (BOP->getOpcode() == BO_EQ || BOP->getOpcode() == BO_NE) {
|
|
|
1452 if (BOP->getOpcode() == BO_NE)
|
|
|
1453 Negate = !Negate;
|
|
|
1454
|
|
|
1455 bool TCond = false;
|
|
|
1456 if (getStaticBooleanValue(BOP->getRHS(), TCond)) {
|
|
|
1457 if (!TCond) Negate = !Negate;
|
|
|
1458 return getTrylockCallExpr(BOP->getLHS(), C, Negate);
|
|
|
1459 }
|
|
|
1460 TCond = false;
|
|
|
1461 if (getStaticBooleanValue(BOP->getLHS(), TCond)) {
|
|
|
1462 if (!TCond) Negate = !Negate;
|
|
|
1463 return getTrylockCallExpr(BOP->getRHS(), C, Negate);
|
|
|
1464 }
|
|
|
1465 return nullptr;
|
|
|
1466 }
|
|
|
1467 if (BOP->getOpcode() == BO_LAnd) {
|
|
|
1468 // LHS must have been evaluated in a different block.
|
|
|
1469 return getTrylockCallExpr(BOP->getRHS(), C, Negate);
|
|
|
1470 }
|
|
|
1471 if (BOP->getOpcode() == BO_LOr)
|
|
|
1472 return getTrylockCallExpr(BOP->getRHS(), C, Negate);
|
|
|
1473 return nullptr;
|
|
|
1474 } else if (const auto *COP = dyn_cast<ConditionalOperator>(Cond)) {
|
|
|
1475 bool TCond, FCond;
|
|
|
1476 if (getStaticBooleanValue(COP->getTrueExpr(), TCond) &&
|
|
|
1477 getStaticBooleanValue(COP->getFalseExpr(), FCond)) {
|
|
|
1478 if (TCond && !FCond)
|
|
|
1479 return getTrylockCallExpr(COP->getCond(), C, Negate);
|
|
|
1480 if (!TCond && FCond) {
|
|
|
1481 Negate = !Negate;
|
|
|
1482 return getTrylockCallExpr(COP->getCond(), C, Negate);
|
|
|
1483 }
|
|
|
1484 }
|
|
|
1485 }
|
|
|
1486 return nullptr;
|
|
|
1487 }
|
|
|
1488
|
|
|
1489 /// Find the lockset that holds on the edge between PredBlock
|
|
|
1490 /// and CurrBlock. The edge set is the exit set of PredBlock (passed
|
|
|
1491 /// as the ExitSet parameter) plus any trylocks, which are conditionally held.
|
|
|
1492 void ThreadSafetyAnalyzer::getEdgeLockset(FactSet& Result,
|
|
|
1493 const FactSet &ExitSet,
|
|
|
1494 const CFGBlock *PredBlock,
|
|
|
1495 const CFGBlock *CurrBlock) {
|
|
|
1496 Result = ExitSet;
|
|
|
1497
|
|
|
1498 const Stmt *Cond = PredBlock->getTerminatorCondition();
|
|
|
1499 // We don't acquire try-locks on ?: branches, only when its result is used.
|
|
|
1500 if (!Cond || isa<ConditionalOperator>(PredBlock->getTerminatorStmt()))
|
|
|
1501 return;
|
|
|
1502
|
|
|
1503 bool Negate = false;
|
|
|
1504 const CFGBlockInfo *PredBlockInfo = &BlockInfo[PredBlock->getBlockID()];
|
|
|
1505 const LocalVarContext &LVarCtx = PredBlockInfo->ExitContext;
|
|
|
1506 StringRef CapDiagKind = "mutex";
|
|
|
1507
|
|
|
1508 const auto *Exp = getTrylockCallExpr(Cond, LVarCtx, Negate);
|
|
|
1509 if (!Exp)
|
|
|
1510 return;
|
|
|
1511
|
|
|
1512 auto *FunDecl = dyn_cast_or_null<NamedDecl>(Exp->getCalleeDecl());
|
|
|
1513 if(!FunDecl || !FunDecl->hasAttrs())
|
|
|
1514 return;
|
|
|
1515
|
|
|
1516 CapExprSet ExclusiveLocksToAdd;
|
|
|
1517 CapExprSet SharedLocksToAdd;
|
|
|
1518
|
|
|
1519 // If the condition is a call to a Trylock function, then grab the attributes
|
|
|
1520 for (const auto *Attr : FunDecl->attrs()) {
|
|
|
1521 switch (Attr->getKind()) {
|
|
|
1522 case attr::TryAcquireCapability: {
|
|
|
1523 auto *A = cast<TryAcquireCapabilityAttr>(Attr);
|
|
|
1524 getMutexIDs(A->isShared() ? SharedLocksToAdd : ExclusiveLocksToAdd, A,
|
|
|
1525 Exp, FunDecl, PredBlock, CurrBlock, A->getSuccessValue(),
|
|
|
1526 Negate);
|
|
|
1527 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
1528 break;
|
|
|
1529 };
|
|
|
1530 case attr::ExclusiveTrylockFunction: {
|
|
|
1531 const auto *A = cast<ExclusiveTrylockFunctionAttr>(Attr);
|
|
|
1532 getMutexIDs(ExclusiveLocksToAdd, A, Exp, FunDecl,
|
|
|
1533 PredBlock, CurrBlock, A->getSuccessValue(), Negate);
|
|
|
1534 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
1535 break;
|
|
|
1536 }
|
|
|
1537 case attr::SharedTrylockFunction: {
|
|
|
1538 const auto *A = cast<SharedTrylockFunctionAttr>(Attr);
|
|
|
1539 getMutexIDs(SharedLocksToAdd, A, Exp, FunDecl,
|
|
|
1540 PredBlock, CurrBlock, A->getSuccessValue(), Negate);
|
|
|
1541 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
1542 break;
|
|
|
1543 }
|
|
|
1544 default:
|
|
|
1545 break;
|
|
|
1546 }
|
|
|
1547 }
|
|
|
1548
|
|
|
1549 // Add and remove locks.
|
|
|
1550 SourceLocation Loc = Exp->getExprLoc();
|
|
|
1551 for (const auto &ExclusiveLockToAdd : ExclusiveLocksToAdd)
|
|
|
1552 addLock(Result, std::make_unique<LockableFactEntry>(ExclusiveLockToAdd,
|
|
|
1553 LK_Exclusive, Loc),
|
|
|
1554 CapDiagKind);
|
|
|
1555 for (const auto &SharedLockToAdd : SharedLocksToAdd)
|
|
|
1556 addLock(Result, std::make_unique<LockableFactEntry>(SharedLockToAdd,
|
|
|
1557 LK_Shared, Loc),
|
|
|
1558 CapDiagKind);
|
|
|
1559 }
|
|
|
1560
|
|
|
1561 namespace {
|
|
|
1562
|
|
|
1563 /// We use this class to visit different types of expressions in
|
|
|
1564 /// CFGBlocks, and build up the lockset.
|
|
|
1565 /// An expression may cause us to add or remove locks from the lockset, or else
|
|
|
1566 /// output error messages related to missing locks.
|
|
|
1567 /// FIXME: In future, we may be able to not inherit from a visitor.
|
|
|
1568 class BuildLockset : public ConstStmtVisitor<BuildLockset> {
|
|
|
1569 friend class ThreadSafetyAnalyzer;
|
|
|
1570
|
|
|
1571 ThreadSafetyAnalyzer *Analyzer;
|
|
|
1572 FactSet FSet;
|
|
|
1573 LocalVariableMap::Context LVarCtx;
|
|
|
1574 unsigned CtxIndex;
|
|
|
1575
|
|
|
1576 // helper functions
|
|
|
1577 void warnIfMutexNotHeld(const NamedDecl *D, const Expr *Exp, AccessKind AK,
|
|
|
1578 Expr *MutexExp, ProtectedOperationKind POK,
|
|
|
1579 StringRef DiagKind, SourceLocation Loc);
|
|
|
1580 void warnIfMutexHeld(const NamedDecl *D, const Expr *Exp, Expr *MutexExp,
|
|
|
1581 StringRef DiagKind);
|
|
|
1582
|
|
|
1583 void checkAccess(const Expr *Exp, AccessKind AK,
|
|
|
1584 ProtectedOperationKind POK = POK_VarAccess);
|
|
|
1585 void checkPtAccess(const Expr *Exp, AccessKind AK,
|
|
|
1586 ProtectedOperationKind POK = POK_VarAccess);
|
|
|
1587
|
|
|
1588 void handleCall(const Expr *Exp, const NamedDecl *D, VarDecl *VD = nullptr);
|
|
|
1589 void examineArguments(const FunctionDecl *FD,
|
|
|
1590 CallExpr::const_arg_iterator ArgBegin,
|
|
|
1591 CallExpr::const_arg_iterator ArgEnd,
|
|
|
1592 bool SkipFirstParam = false);
|
|
|
1593
|
|
|
1594 public:
|
|
|
1595 BuildLockset(ThreadSafetyAnalyzer *Anlzr, CFGBlockInfo &Info)
|
|
|
1596 : ConstStmtVisitor<BuildLockset>(), Analyzer(Anlzr), FSet(Info.EntrySet),
|
|
|
1597 LVarCtx(Info.EntryContext), CtxIndex(Info.EntryIndex) {}
|
|
|
1598
|
|
|
1599 void VisitUnaryOperator(const UnaryOperator *UO);
|
|
|
1600 void VisitBinaryOperator(const BinaryOperator *BO);
|
|
|
1601 void VisitCastExpr(const CastExpr *CE);
|
|
|
1602 void VisitCallExpr(const CallExpr *Exp);
|
|
|
1603 void VisitCXXConstructExpr(const CXXConstructExpr *Exp);
|
|
|
1604 void VisitDeclStmt(const DeclStmt *S);
|
|
|
1605 };
|
|
|
1606
|
|
|
1607 } // namespace
|
|
|
1608
|
|
|
1609 /// Warn if the LSet does not contain a lock sufficient to protect access
|
|
|
1610 /// of at least the passed in AccessKind.
|
|
|
1611 void BuildLockset::warnIfMutexNotHeld(const NamedDecl *D, const Expr *Exp,
|
|
|
1612 AccessKind AK, Expr *MutexExp,
|
|
|
1613 ProtectedOperationKind POK,
|
|
|
1614 StringRef DiagKind, SourceLocation Loc) {
|
|
|
1615 LockKind LK = getLockKindFromAccessKind(AK);
|
|
|
1616
|
|
|
1617 CapabilityExpr Cp = Analyzer->SxBuilder.translateAttrExpr(MutexExp, D, Exp);
|
|
|
1618 if (Cp.isInvalid()) {
|
|
|
1619 warnInvalidLock(Analyzer->Handler, MutexExp, D, Exp, DiagKind);
|
|
|
1620 return;
|
|
|
1621 } else if (Cp.shouldIgnore()) {
|
|
|
1622 return;
|
|
|
1623 }
|
|
|
1624
|
|
|
1625 if (Cp.negative()) {
|
|
|
1626 // Negative capabilities act like locks excluded
|
|
|
1627 const FactEntry *LDat = FSet.findLock(Analyzer->FactMan, !Cp);
|
|
|
1628 if (LDat) {
|
|
|
1629 Analyzer->Handler.handleFunExcludesLock(
|
|
|
1630 DiagKind, D->getNameAsString(), (!Cp).toString(), Loc);
|
|
|
1631 return;
|
|
|
1632 }
|
|
|
1633
|
|
|
1634 // If this does not refer to a negative capability in the same class,
|
|
|
1635 // then stop here.
|
|
|
1636 if (!Analyzer->inCurrentScope(Cp))
|
|
|
1637 return;
|
|
|
1638
|
|
|
1639 // Otherwise the negative requirement must be propagated to the caller.
|
|
|
1640 LDat = FSet.findLock(Analyzer->FactMan, Cp);
|
|
|
1641 if (!LDat) {
|
|
|
1642 Analyzer->Handler.handleMutexNotHeld("", D, POK, Cp.toString(),
|
|
|
1643 LK_Shared, Loc);
|
|
|
1644 }
|
|
|
1645 return;
|
|
|
1646 }
|
|
|
1647
|
|
|
1648 const FactEntry *LDat = FSet.findLockUniv(Analyzer->FactMan, Cp);
|
|
|
1649 bool NoError = true;
|
|
|
1650 if (!LDat) {
|
|
|
1651 // No exact match found. Look for a partial match.
|
|
|
1652 LDat = FSet.findPartialMatch(Analyzer->FactMan, Cp);
|
|
|
1653 if (LDat) {
|
|
|
1654 // Warn that there's no precise match.
|
|
|
1655 std::string PartMatchStr = LDat->toString();
|
|
|
1656 StringRef PartMatchName(PartMatchStr);
|
|
|
1657 Analyzer->Handler.handleMutexNotHeld(DiagKind, D, POK, Cp.toString(),
|
|
|
1658 LK, Loc, &PartMatchName);
|
|
|
1659 } else {
|
|
|
1660 // Warn that there's no match at all.
|
|
|
1661 Analyzer->Handler.handleMutexNotHeld(DiagKind, D, POK, Cp.toString(),
|
|
|
1662 LK, Loc);
|
|
|
1663 }
|
|
|
1664 NoError = false;
|
|
|
1665 }
|
|
|
1666 // Make sure the mutex we found is the right kind.
|
|
|
1667 if (NoError && LDat && !LDat->isAtLeast(LK)) {
|
|
|
1668 Analyzer->Handler.handleMutexNotHeld(DiagKind, D, POK, Cp.toString(),
|
|
|
1669 LK, Loc);
|
|
|
1670 }
|
|
|
1671 }
|
|
|
1672
|
|
|
1673 /// Warn if the LSet contains the given lock.
|
|
|
1674 void BuildLockset::warnIfMutexHeld(const NamedDecl *D, const Expr *Exp,
|
|
|
1675 Expr *MutexExp, StringRef DiagKind) {
|
|
|
1676 CapabilityExpr Cp = Analyzer->SxBuilder.translateAttrExpr(MutexExp, D, Exp);
|
|
|
1677 if (Cp.isInvalid()) {
|
|
|
1678 warnInvalidLock(Analyzer->Handler, MutexExp, D, Exp, DiagKind);
|
|
|
1679 return;
|
|
|
1680 } else if (Cp.shouldIgnore()) {
|
|
|
1681 return;
|
|
|
1682 }
|
|
|
1683
|
|
|
1684 const FactEntry *LDat = FSet.findLock(Analyzer->FactMan, Cp);
|
|
|
1685 if (LDat) {
|
|
|
1686 Analyzer->Handler.handleFunExcludesLock(
|
|
|
1687 DiagKind, D->getNameAsString(), Cp.toString(), Exp->getExprLoc());
|
|
|
1688 }
|
|
|
1689 }
|
|
|
1690
|
|
|
1691 /// Checks guarded_by and pt_guarded_by attributes.
|
|
|
1692 /// Whenever we identify an access (read or write) to a DeclRefExpr that is
|
|
|
1693 /// marked with guarded_by, we must ensure the appropriate mutexes are held.
|
|
|
1694 /// Similarly, we check if the access is to an expression that dereferences
|
|
|
1695 /// a pointer marked with pt_guarded_by.
|
|
|
1696 void BuildLockset::checkAccess(const Expr *Exp, AccessKind AK,
|
|
|
1697 ProtectedOperationKind POK) {
|
|
|
1698 Exp = Exp->IgnoreImplicit()->IgnoreParenCasts();
|
|
|
1699
|
|
|
1700 SourceLocation Loc = Exp->getExprLoc();
|
|
|
1701
|
|
|
1702 // Local variables of reference type cannot be re-assigned;
|
|
|
1703 // map them to their initializer.
|
|
|
1704 while (const auto *DRE = dyn_cast<DeclRefExpr>(Exp)) {
|
|
|
1705 const auto *VD = dyn_cast<VarDecl>(DRE->getDecl()->getCanonicalDecl());
|
|
|
1706 if (VD && VD->isLocalVarDecl() && VD->getType()->isReferenceType()) {
|
|
|
1707 if (const auto *E = VD->getInit()) {
|
|
|
1708 // Guard against self-initialization. e.g., int &i = i;
|
|
|
1709 if (E == Exp)
|
|
|
1710 break;
|
|
|
1711 Exp = E;
|
|
|
1712 continue;
|
|
|
1713 }
|
|
|
1714 }
|
|
|
1715 break;
|
|
|
1716 }
|
|
|
1717
|
|
|
1718 if (const auto *UO = dyn_cast<UnaryOperator>(Exp)) {
|
|
|
1719 // For dereferences
|
|
|
1720 if (UO->getOpcode() == UO_Deref)
|
|
|
1721 checkPtAccess(UO->getSubExpr(), AK, POK);
|
|
|
1722 return;
|
|
|
1723 }
|
|
|
1724
|
|
|
1725 if (const auto *AE = dyn_cast<ArraySubscriptExpr>(Exp)) {
|
|
|
1726 checkPtAccess(AE->getLHS(), AK, POK);
|
|
|
1727 return;
|
|
|
1728 }
|
|
|
1729
|
|
|
1730 if (const auto *ME = dyn_cast<MemberExpr>(Exp)) {
|
|
|
1731 if (ME->isArrow())
|
|
|
1732 checkPtAccess(ME->getBase(), AK, POK);
|
|
|
1733 else
|
|
|
1734 checkAccess(ME->getBase(), AK, POK);
|
|
|
1735 }
|
|
|
1736
|
|
|
1737 const ValueDecl *D = getValueDecl(Exp);
|
|
|
1738 if (!D || !D->hasAttrs())
|
|
|
1739 return;
|
|
|
1740
|
|
|
1741 if (D->hasAttr<GuardedVarAttr>() && FSet.isEmpty(Analyzer->FactMan)) {
|
|
|
1742 Analyzer->Handler.handleNoMutexHeld("mutex", D, POK, AK, Loc);
|
|
|
1743 }
|
|
|
1744
|
|
|
1745 for (const auto *I : D->specific_attrs<GuardedByAttr>())
|
|
|
1746 warnIfMutexNotHeld(D, Exp, AK, I->getArg(), POK,
|
|
|
1747 ClassifyDiagnostic(I), Loc);
|
|
|
1748 }
|
|
|
1749
|
|
|
1750 /// Checks pt_guarded_by and pt_guarded_var attributes.
|
|
|
1751 /// POK is the same operationKind that was passed to checkAccess.
|
|
|
1752 void BuildLockset::checkPtAccess(const Expr *Exp, AccessKind AK,
|
|
|
1753 ProtectedOperationKind POK) {
|
|
|
1754 while (true) {
|
|
|
1755 if (const auto *PE = dyn_cast<ParenExpr>(Exp)) {
|
|
|
1756 Exp = PE->getSubExpr();
|
|
|
1757 continue;
|
|
|
1758 }
|
|
|
1759 if (const auto *CE = dyn_cast<CastExpr>(Exp)) {
|
|
|
1760 if (CE->getCastKind() == CK_ArrayToPointerDecay) {
|
|
|
1761 // If it's an actual array, and not a pointer, then it's elements
|
|
|
1762 // are protected by GUARDED_BY, not PT_GUARDED_BY;
|
|
|
1763 checkAccess(CE->getSubExpr(), AK, POK);
|
|
|
1764 return;
|
|
|
1765 }
|
|
|
1766 Exp = CE->getSubExpr();
|
|
|
1767 continue;
|
|
|
1768 }
|
|
|
1769 break;
|
|
|
1770 }
|
|
|
1771
|
|
|
1772 // Pass by reference warnings are under a different flag.
|
|
|
1773 ProtectedOperationKind PtPOK = POK_VarDereference;
|
|
|
1774 if (POK == POK_PassByRef) PtPOK = POK_PtPassByRef;
|
|
|
1775
|
|
|
1776 const ValueDecl *D = getValueDecl(Exp);
|
|
|
1777 if (!D || !D->hasAttrs())
|
|
|
1778 return;
|
|
|
1779
|
|
|
1780 if (D->hasAttr<PtGuardedVarAttr>() && FSet.isEmpty(Analyzer->FactMan))
|
|
|
1781 Analyzer->Handler.handleNoMutexHeld("mutex", D, PtPOK, AK,
|
|
|
1782 Exp->getExprLoc());
|
|
|
1783
|
|
|
1784 for (auto const *I : D->specific_attrs<PtGuardedByAttr>())
|
|
|
1785 warnIfMutexNotHeld(D, Exp, AK, I->getArg(), PtPOK,
|
|
|
1786 ClassifyDiagnostic(I), Exp->getExprLoc());
|
|
|
1787 }
|
|
|
1788
|
|
|
1789 /// Process a function call, method call, constructor call,
|
|
|
1790 /// or destructor call. This involves looking at the attributes on the
|
|
|
1791 /// corresponding function/method/constructor/destructor, issuing warnings,
|
|
|
1792 /// and updating the locksets accordingly.
|
|
|
1793 ///
|
|
|
1794 /// FIXME: For classes annotated with one of the guarded annotations, we need
|
|
|
1795 /// to treat const method calls as reads and non-const method calls as writes,
|
|
|
1796 /// and check that the appropriate locks are held. Non-const method calls with
|
|
|
1797 /// the same signature as const method calls can be also treated as reads.
|
|
|
1798 ///
|
|
|
1799 void BuildLockset::handleCall(const Expr *Exp, const NamedDecl *D,
|
|
|
1800 VarDecl *VD) {
|
|
|
1801 SourceLocation Loc = Exp->getExprLoc();
|
|
|
1802 CapExprSet ExclusiveLocksToAdd, SharedLocksToAdd;
|
|
|
1803 CapExprSet ExclusiveLocksToRemove, SharedLocksToRemove, GenericLocksToRemove;
|
|
|
1804 CapExprSet ScopedExclusiveReqs, ScopedSharedReqs;
|
|
|
1805 StringRef CapDiagKind = "mutex";
|
|
|
1806
|
|
|
1807 // Figure out if we're constructing an object of scoped lockable class
|
|
|
1808 bool isScopedVar = false;
|
|
|
1809 if (VD) {
|
|
|
1810 if (const auto *CD = dyn_cast<const CXXConstructorDecl>(D)) {
|
|
|
1811 const CXXRecordDecl* PD = CD->getParent();
|
|
|
1812 if (PD && PD->hasAttr<ScopedLockableAttr>())
|
|
|
1813 isScopedVar = true;
|
|
|
1814 }
|
|
|
1815 }
|
|
|
1816
|
|
|
1817 for(const Attr *At : D->attrs()) {
|
|
|
1818 switch (At->getKind()) {
|
|
|
1819 // When we encounter a lock function, we need to add the lock to our
|
|
|
1820 // lockset.
|
|
|
1821 case attr::AcquireCapability: {
|
|
|
1822 const auto *A = cast<AcquireCapabilityAttr>(At);
|
|
|
1823 Analyzer->getMutexIDs(A->isShared() ? SharedLocksToAdd
|
|
|
1824 : ExclusiveLocksToAdd,
|
|
|
1825 A, Exp, D, VD);
|
|
|
1826
|
|
|
1827 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
1828 break;
|
|
|
1829 }
|
|
|
1830
|
|
|
1831 // An assert will add a lock to the lockset, but will not generate
|
|
|
1832 // a warning if it is already there, and will not generate a warning
|
|
|
1833 // if it is not removed.
|
|
|
1834 case attr::AssertExclusiveLock: {
|
|
|
1835 const auto *A = cast<AssertExclusiveLockAttr>(At);
|
|
|
1836
|
|
|
1837 CapExprSet AssertLocks;
|
|
|
1838 Analyzer->getMutexIDs(AssertLocks, A, Exp, D, VD);
|
|
|
1839 for (const auto &AssertLock : AssertLocks)
|
|
|
1840 Analyzer->addLock(FSet,
|
|
|
1841 std::make_unique<LockableFactEntry>(
|
|
|
1842 AssertLock, LK_Exclusive, Loc, false, true),
|
|
|
1843 ClassifyDiagnostic(A));
|
|
|
1844 break;
|
|
|
1845 }
|
|
|
1846 case attr::AssertSharedLock: {
|
|
|
1847 const auto *A = cast<AssertSharedLockAttr>(At);
|
|
|
1848
|
|
|
1849 CapExprSet AssertLocks;
|
|
|
1850 Analyzer->getMutexIDs(AssertLocks, A, Exp, D, VD);
|
|
|
1851 for (const auto &AssertLock : AssertLocks)
|
|
|
1852 Analyzer->addLock(FSet,
|
|
|
1853 std::make_unique<LockableFactEntry>(
|
|
|
1854 AssertLock, LK_Shared, Loc, false, true),
|
|
|
1855 ClassifyDiagnostic(A));
|
|
|
1856 break;
|
|
|
1857 }
|
|
|
1858
|
|
|
1859 case attr::AssertCapability: {
|
|
|
1860 const auto *A = cast<AssertCapabilityAttr>(At);
|
|
|
1861 CapExprSet AssertLocks;
|
|
|
1862 Analyzer->getMutexIDs(AssertLocks, A, Exp, D, VD);
|
|
|
1863 for (const auto &AssertLock : AssertLocks)
|
|
|
1864 Analyzer->addLock(FSet,
|
|
|
1865 std::make_unique<LockableFactEntry>(
|
|
|
1866 AssertLock,
|
|
|
1867 A->isShared() ? LK_Shared : LK_Exclusive, Loc,
|
|
|
1868 false, true),
|
|
|
1869 ClassifyDiagnostic(A));
|
|
|
1870 break;
|
|
|
1871 }
|
|
|
1872
|
|
|
1873 // When we encounter an unlock function, we need to remove unlocked
|
|
|
1874 // mutexes from the lockset, and flag a warning if they are not there.
|
|
|
1875 case attr::ReleaseCapability: {
|
|
|
1876 const auto *A = cast<ReleaseCapabilityAttr>(At);
|
|
|
1877 if (A->isGeneric())
|
|
|
1878 Analyzer->getMutexIDs(GenericLocksToRemove, A, Exp, D, VD);
|
|
|
1879 else if (A->isShared())
|
|
|
1880 Analyzer->getMutexIDs(SharedLocksToRemove, A, Exp, D, VD);
|
|
|
1881 else
|
|
|
1882 Analyzer->getMutexIDs(ExclusiveLocksToRemove, A, Exp, D, VD);
|
|
|
1883
|
|
|
1884 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
1885 break;
|
|
|
1886 }
|
|
|
1887
|
|
|
1888 case attr::RequiresCapability: {
|
|
|
1889 const auto *A = cast<RequiresCapabilityAttr>(At);
|
|
|
1890 for (auto *Arg : A->args()) {
|
|
|
1891 warnIfMutexNotHeld(D, Exp, A->isShared() ? AK_Read : AK_Written, Arg,
|
|
|
1892 POK_FunctionCall, ClassifyDiagnostic(A),
|
|
|
1893 Exp->getExprLoc());
|
|
|
1894 // use for adopting a lock
|
|
|
1895 if (isScopedVar) {
|
|
|
1896 Analyzer->getMutexIDs(A->isShared() ? ScopedSharedReqs
|
|
|
1897 : ScopedExclusiveReqs,
|
|
|
1898 A, Exp, D, VD);
|
|
|
1899 }
|
|
|
1900 }
|
|
|
1901 break;
|
|
|
1902 }
|
|
|
1903
|
|
|
1904 case attr::LocksExcluded: {
|
|
|
1905 const auto *A = cast<LocksExcludedAttr>(At);
|
|
|
1906 for (auto *Arg : A->args())
|
|
|
1907 warnIfMutexHeld(D, Exp, Arg, ClassifyDiagnostic(A));
|
|
|
1908 break;
|
|
|
1909 }
|
|
|
1910
|
|
|
1911 // Ignore attributes unrelated to thread-safety
|
|
|
1912 default:
|
|
|
1913 break;
|
|
|
1914 }
|
|
|
1915 }
|
|
|
1916
|
|
|
1917 // Remove locks first to allow lock upgrading/downgrading.
|
|
|
1918 // FIXME -- should only fully remove if the attribute refers to 'this'.
|
|
|
1919 bool Dtor = isa<CXXDestructorDecl>(D);
|
|
|
1920 for (const auto &M : ExclusiveLocksToRemove)
|
|
|
1921 Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Exclusive, CapDiagKind);
|
|
|
1922 for (const auto &M : SharedLocksToRemove)
|
|
|
1923 Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Shared, CapDiagKind);
|
|
|
1924 for (const auto &M : GenericLocksToRemove)
|
|
|
1925 Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Generic, CapDiagKind);
|
|
|
1926
|
|
|
1927 // Add locks.
|
|
|
1928 for (const auto &M : ExclusiveLocksToAdd)
|
|
|
1929 Analyzer->addLock(FSet, std::make_unique<LockableFactEntry>(
|
|
|
1930 M, LK_Exclusive, Loc, isScopedVar),
|
|
|
1931 CapDiagKind);
|
|
|
1932 for (const auto &M : SharedLocksToAdd)
|
|
|
1933 Analyzer->addLock(FSet, std::make_unique<LockableFactEntry>(
|
|
|
1934 M, LK_Shared, Loc, isScopedVar),
|
|
|
1935 CapDiagKind);
|
|
|
1936
|
|
|
1937 if (isScopedVar) {
|
|
|
1938 // Add the managing object as a dummy mutex, mapped to the underlying mutex.
|
|
|
1939 SourceLocation MLoc = VD->getLocation();
|
|
|
1940 DeclRefExpr DRE(VD->getASTContext(), VD, false, VD->getType(), VK_LValue,
|
|
|
1941 VD->getLocation());
|
|
|
1942 // FIXME: does this store a pointer to DRE?
|
|
|
1943 CapabilityExpr Scp = Analyzer->SxBuilder.translateAttrExpr(&DRE, nullptr);
|
|
|
1944
|
|
|
1945 auto ScopedEntry = std::make_unique<ScopedLockableFactEntry>(Scp, MLoc);
|
|
|
1946 for (const auto &M : ExclusiveLocksToAdd)
|
|
|
1947 ScopedEntry->addExclusiveLock(M);
|
|
|
1948 for (const auto &M : ScopedExclusiveReqs)
|
|
|
1949 ScopedEntry->addExclusiveLock(M);
|
|
|
1950 for (const auto &M : SharedLocksToAdd)
|
|
|
1951 ScopedEntry->addSharedLock(M);
|
|
|
1952 for (const auto &M : ScopedSharedReqs)
|
|
|
1953 ScopedEntry->addSharedLock(M);
|
|
|
1954 for (const auto &M : ExclusiveLocksToRemove)
|
|
|
1955 ScopedEntry->addExclusiveUnlock(M);
|
|
|
1956 for (const auto &M : SharedLocksToRemove)
|
|
|
1957 ScopedEntry->addSharedUnlock(M);
|
|
|
1958 Analyzer->addLock(FSet, std::move(ScopedEntry), CapDiagKind);
|
|
|
1959 }
|
|
|
1960 }
|
|
|
1961
|
|
|
1962 /// For unary operations which read and write a variable, we need to
|
|
|
1963 /// check whether we hold any required mutexes. Reads are checked in
|
|
|
1964 /// VisitCastExpr.
|
|
|
1965 void BuildLockset::VisitUnaryOperator(const UnaryOperator *UO) {
|
|
|
1966 switch (UO->getOpcode()) {
|
|
|
1967 case UO_PostDec:
|
|
|
1968 case UO_PostInc:
|
|
|
1969 case UO_PreDec:
|
|
|
1970 case UO_PreInc:
|
|
|
1971 checkAccess(UO->getSubExpr(), AK_Written);
|
|
|
1972 break;
|
|
|
1973 default:
|
|
|
1974 break;
|
|
|
1975 }
|
|
|
1976 }
|
|
|
1977
|
|
|
1978 /// For binary operations which assign to a variable (writes), we need to check
|
|
|
1979 /// whether we hold any required mutexes.
|
|
|
1980 /// FIXME: Deal with non-primitive types.
|
|
|
1981 void BuildLockset::VisitBinaryOperator(const BinaryOperator *BO) {
|
|
|
1982 if (!BO->isAssignmentOp())
|
|
|
1983 return;
|
|
|
1984
|
|
|
1985 // adjust the context
|
|
|
1986 LVarCtx = Analyzer->LocalVarMap.getNextContext(CtxIndex, BO, LVarCtx);
|
|
|
1987
|
|
|
1988 checkAccess(BO->getLHS(), AK_Written);
|
|
|
1989 }
|
|
|
1990
|
|
|
1991 /// Whenever we do an LValue to Rvalue cast, we are reading a variable and
|
|
|
1992 /// need to ensure we hold any required mutexes.
|
|
|
1993 /// FIXME: Deal with non-primitive types.
|
|
|
1994 void BuildLockset::VisitCastExpr(const CastExpr *CE) {
|
|
|
1995 if (CE->getCastKind() != CK_LValueToRValue)
|
|
|
1996 return;
|
|
|
1997 checkAccess(CE->getSubExpr(), AK_Read);
|
|
|
1998 }
|
|
|
1999
|
|
|
2000 void BuildLockset::examineArguments(const FunctionDecl *FD,
|
|
|
2001 CallExpr::const_arg_iterator ArgBegin,
|
|
|
2002 CallExpr::const_arg_iterator ArgEnd,
|
|
|
2003 bool SkipFirstParam) {
|
|
|
2004 // Currently we can't do anything if we don't know the function declaration.
|
|
|
2005 if (!FD)
|
|
|
2006 return;
|
|
|
2007
|
|
|
2008 // NO_THREAD_SAFETY_ANALYSIS does double duty here. Normally it
|
|
|
2009 // only turns off checking within the body of a function, but we also
|
|
|
2010 // use it to turn off checking in arguments to the function. This
|
|
|
2011 // could result in some false negatives, but the alternative is to
|
|
|
2012 // create yet another attribute.
|
|
|
2013 if (FD->hasAttr<NoThreadSafetyAnalysisAttr>())
|
|
|
2014 return;
|
|
|
2015
|
|
|
2016 const ArrayRef<ParmVarDecl *> Params = FD->parameters();
|
|
|
2017 auto Param = Params.begin();
|
|
|
2018 if (SkipFirstParam)
|
|
|
2019 ++Param;
|
|
|
2020
|
|
|
2021 // There can be default arguments, so we stop when one iterator is at end().
|
|
|
2022 for (auto Arg = ArgBegin; Param != Params.end() && Arg != ArgEnd;
|
|
|
2023 ++Param, ++Arg) {
|
|
|
2024 QualType Qt = (*Param)->getType();
|
|
|
2025 if (Qt->isReferenceType())
|
|
|
2026 checkAccess(*Arg, AK_Read, POK_PassByRef);
|
|
|
2027 }
|
|
|
2028 }
|
|
|
2029
|
|
|
2030 void BuildLockset::VisitCallExpr(const CallExpr *Exp) {
|
|
|
2031 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(Exp)) {
|
|
|
2032 const auto *ME = dyn_cast<MemberExpr>(CE->getCallee());
|
|
|
2033 // ME can be null when calling a method pointer
|
|
|
2034 const CXXMethodDecl *MD = CE->getMethodDecl();
|
|
|
2035
|
|
|
2036 if (ME && MD) {
|
|
|
2037 if (ME->isArrow()) {
|
|
|
2038 if (MD->isConst())
|
|
|
2039 checkPtAccess(CE->getImplicitObjectArgument(), AK_Read);
|
|
|
2040 else // FIXME -- should be AK_Written
|
|
|
2041 checkPtAccess(CE->getImplicitObjectArgument(), AK_Read);
|
|
|
2042 } else {
|
|
|
2043 if (MD->isConst())
|
|
|
2044 checkAccess(CE->getImplicitObjectArgument(), AK_Read);
|
|
|
2045 else // FIXME -- should be AK_Written
|
|
|
2046 checkAccess(CE->getImplicitObjectArgument(), AK_Read);
|
|
|
2047 }
|
|
|
2048 }
|
|
|
2049
|
|
|
2050 examineArguments(CE->getDirectCallee(), CE->arg_begin(), CE->arg_end());
|
|
|
2051 } else if (const auto *OE = dyn_cast<CXXOperatorCallExpr>(Exp)) {
|
|
|
2052 auto OEop = OE->getOperator();
|
|
|
2053 switch (OEop) {
|
|
|
2054 case OO_Equal: {
|
|
|
2055 const Expr *Target = OE->getArg(0);
|
|
|
2056 const Expr *Source = OE->getArg(1);
|
|
|
2057 checkAccess(Target, AK_Written);
|
|
|
2058 checkAccess(Source, AK_Read);
|
|
|
2059 break;
|
|
|
2060 }
|
|
|
2061 case OO_Star:
|
|
|
2062 case OO_Arrow:
|
|
|
2063 case OO_Subscript:
|
|
|
2064 if (!(OEop == OO_Star && OE->getNumArgs() > 1)) {
|
|
|
2065 // Grrr. operator* can be multiplication...
|
|
|
2066 checkPtAccess(OE->getArg(0), AK_Read);
|
|
|
2067 }
|
|
|
2068 LLVM_FALLTHROUGH;
|
|
|
2069 default: {
|
|
|
2070 // TODO: get rid of this, and rely on pass-by-ref instead.
|
|
|
2071 const Expr *Obj = OE->getArg(0);
|
|
|
2072 checkAccess(Obj, AK_Read);
|
|
|
2073 // Check the remaining arguments. For method operators, the first
|
|
|
2074 // argument is the implicit self argument, and doesn't appear in the
|
|
|
2075 // FunctionDecl, but for non-methods it does.
|
|
|
2076 const FunctionDecl *FD = OE->getDirectCallee();
|
|
|
2077 examineArguments(FD, std::next(OE->arg_begin()), OE->arg_end(),
|
|
|
2078 /*SkipFirstParam*/ !isa<CXXMethodDecl>(FD));
|
|
|
2079 break;
|
|
|
2080 }
|
|
|
2081 }
|
|
|
2082 } else {
|
|
|
2083 examineArguments(Exp->getDirectCallee(), Exp->arg_begin(), Exp->arg_end());
|
|
|
2084 }
|
|
|
2085
|
|
|
2086 auto *D = dyn_cast_or_null<NamedDecl>(Exp->getCalleeDecl());
|
|
|
2087 if(!D || !D->hasAttrs())
|
|
|
2088 return;
|
|
|
2089 handleCall(Exp, D);
|
|
|
2090 }
|
|
|
2091
|
|
|
2092 void BuildLockset::VisitCXXConstructExpr(const CXXConstructExpr *Exp) {
|
|
|
2093 const CXXConstructorDecl *D = Exp->getConstructor();
|
|
|
2094 if (D && D->isCopyConstructor()) {
|
|
|
2095 const Expr* Source = Exp->getArg(0);
|
|
|
2096 checkAccess(Source, AK_Read);
|
|
|
2097 } else {
|
|
|
2098 examineArguments(D, Exp->arg_begin(), Exp->arg_end());
|
|
|
2099 }
|
|
|
2100 }
|
|
|
2101
|
|
|
2102 static CXXConstructorDecl *
|
|
|
2103 findConstructorForByValueReturn(const CXXRecordDecl *RD) {
|
|
|
2104 // Prefer a move constructor over a copy constructor. If there's more than
|
|
|
2105 // one copy constructor or more than one move constructor, we arbitrarily
|
|
|
2106 // pick the first declared such constructor rather than trying to guess which
|
|
|
2107 // one is more appropriate.
|
|
|
2108 CXXConstructorDecl *CopyCtor = nullptr;
|
|
|
2109 for (auto *Ctor : RD->ctors()) {
|
|
|
2110 if (Ctor->isDeleted())
|
|
|
2111 continue;
|
|
|
2112 if (Ctor->isMoveConstructor())
|
|
|
2113 return Ctor;
|
|
|
2114 if (!CopyCtor && Ctor->isCopyConstructor())
|
|
|
2115 CopyCtor = Ctor;
|
|
|
2116 }
|
|
|
2117 return CopyCtor;
|
|
|
2118 }
|
|
|
2119
|
|
|
2120 static Expr *buildFakeCtorCall(CXXConstructorDecl *CD, ArrayRef<Expr *> Args,
|
|
|
2121 SourceLocation Loc) {
|
|
|
2122 ASTContext &Ctx = CD->getASTContext();
|
|
|
2123 return CXXConstructExpr::Create(Ctx, Ctx.getRecordType(CD->getParent()), Loc,
|
|
|
2124 CD, true, Args, false, false, false, false,
|
|
|
2125 CXXConstructExpr::CK_Complete,
|
|
|
2126 SourceRange(Loc, Loc));
|
|
|
2127 }
|
|
|
2128
|
|
|
2129 void BuildLockset::VisitDeclStmt(const DeclStmt *S) {
|
|
|
2130 // adjust the context
|
|
|
2131 LVarCtx = Analyzer->LocalVarMap.getNextContext(CtxIndex, S, LVarCtx);
|
|
|
2132
|
|
|
2133 for (auto *D : S->getDeclGroup()) {
|
|
|
2134 if (auto *VD = dyn_cast_or_null<VarDecl>(D)) {
|
|
|
2135 Expr *E = VD->getInit();
|
|
|
2136 if (!E)
|
|
|
2137 continue;
|
|
|
2138 E = E->IgnoreParens();
|
|
|
2139
|
|
|
2140 // handle constructors that involve temporaries
|
|
|
2141 if (auto *EWC = dyn_cast<ExprWithCleanups>(E))
|
|
173
|
2142 E = EWC->getSubExpr()->IgnoreParens();
|
|
|
2143 if (auto *CE = dyn_cast<CastExpr>(E))
|
|
|
2144 if (CE->getCastKind() == CK_NoOp ||
|
|
|
2145 CE->getCastKind() == CK_ConstructorConversion ||
|
|
|
2146 CE->getCastKind() == CK_UserDefinedConversion)
|
|
|
2147 E = CE->getSubExpr()->IgnoreParens();
|
|
150
|
2148 if (auto *BTE = dyn_cast<CXXBindTemporaryExpr>(E))
|
|
173
|
2149 E = BTE->getSubExpr()->IgnoreParens();
|
|
150
|
2150
|
|
|
2151 if (const auto *CE = dyn_cast<CXXConstructExpr>(E)) {
|
|
|
2152 const auto *CtorD = dyn_cast_or_null<NamedDecl>(CE->getConstructor());
|
|
|
2153 if (!CtorD || !CtorD->hasAttrs())
|
|
|
2154 continue;
|
|
|
2155 handleCall(E, CtorD, VD);
|
|
|
2156 } else if (isa<CallExpr>(E) && E->isRValue()) {
|
|
|
2157 // If the object is initialized by a function call that returns a
|
|
|
2158 // scoped lockable by value, use the attributes on the copy or move
|
|
|
2159 // constructor to figure out what effect that should have on the
|
|
|
2160 // lockset.
|
|
|
2161 // FIXME: Is this really the best way to handle this situation?
|
|
|
2162 auto *RD = E->getType()->getAsCXXRecordDecl();
|
|
|
2163 if (!RD || !RD->hasAttr<ScopedLockableAttr>())
|
|
|
2164 continue;
|
|
|
2165 CXXConstructorDecl *CtorD = findConstructorForByValueReturn(RD);
|
|
|
2166 if (!CtorD || !CtorD->hasAttrs())
|
|
|
2167 continue;
|
|
|
2168 handleCall(buildFakeCtorCall(CtorD, {E}, E->getBeginLoc()), CtorD, VD);
|
|
|
2169 }
|
|
|
2170 }
|
|
|
2171 }
|
|
|
2172 }
|
|
|
2173
|
|
|
2174 /// Compute the intersection of two locksets and issue warnings for any
|
|
|
2175 /// locks in the symmetric difference.
|
|
|
2176 ///
|
|
|
2177 /// This function is used at a merge point in the CFG when comparing the lockset
|
|
|
2178 /// of each branch being merged. For example, given the following sequence:
|
|
|
2179 /// A; if () then B; else C; D; we need to check that the lockset after B and C
|
|
|
2180 /// are the same. In the event of a difference, we use the intersection of these
|
|
|
2181 /// two locksets at the start of D.
|
|
|
2182 ///
|
|
|
2183 /// \param FSet1 The first lockset.
|
|
|
2184 /// \param FSet2 The second lockset.
|
|
|
2185 /// \param JoinLoc The location of the join point for error reporting
|
|
|
2186 /// \param LEK1 The error message to report if a mutex is missing from LSet1
|
|
|
2187 /// \param LEK2 The error message to report if a mutex is missing from Lset2
|
|
|
2188 void ThreadSafetyAnalyzer::intersectAndWarn(FactSet &FSet1,
|
|
|
2189 const FactSet &FSet2,
|
|
|
2190 SourceLocation JoinLoc,
|
|
|
2191 LockErrorKind LEK1,
|
|
|
2192 LockErrorKind LEK2,
|
|
|
2193 bool Modify) {
|
|
|
2194 FactSet FSet1Orig = FSet1;
|
|
|
2195
|
|
|
2196 // Find locks in FSet2 that conflict or are not in FSet1, and warn.
|
|
|
2197 for (const auto &Fact : FSet2) {
|
|
|
2198 const FactEntry *LDat1 = nullptr;
|
|
|
2199 const FactEntry *LDat2 = &FactMan[Fact];
|
|
|
2200 FactSet::iterator Iter1 = FSet1.findLockIter(FactMan, *LDat2);
|
|
|
2201 if (Iter1 != FSet1.end()) LDat1 = &FactMan[*Iter1];
|
|
|
2202
|
|
|
2203 if (LDat1) {
|
|
|
2204 if (LDat1->kind() != LDat2->kind()) {
|
|
|
2205 Handler.handleExclusiveAndShared("mutex", LDat2->toString(),
|
|
|
2206 LDat2->loc(), LDat1->loc());
|
|
|
2207 if (Modify && LDat1->kind() != LK_Exclusive) {
|
|
|
2208 // Take the exclusive lock, which is the one in FSet2.
|
|
|
2209 *Iter1 = Fact;
|
|
|
2210 }
|
|
|
2211 }
|
|
|
2212 else if (Modify && LDat1->asserted() && !LDat2->asserted()) {
|
|
|
2213 // The non-asserted lock in FSet2 is the one we want to track.
|
|
|
2214 *Iter1 = Fact;
|
|
|
2215 }
|
|
|
2216 } else {
|
|
|
2217 LDat2->handleRemovalFromIntersection(FSet2, FactMan, JoinLoc, LEK1,
|
|
|
2218 Handler);
|
|
|
2219 }
|
|
|
2220 }
|
|
|
2221
|
|
|
2222 // Find locks in FSet1 that are not in FSet2, and remove them.
|
|
|
2223 for (const auto &Fact : FSet1Orig) {
|
|
|
2224 const FactEntry *LDat1 = &FactMan[Fact];
|
|
|
2225 const FactEntry *LDat2 = FSet2.findLock(FactMan, *LDat1);
|
|
|
2226
|
|
|
2227 if (!LDat2) {
|
|
|
2228 LDat1->handleRemovalFromIntersection(FSet1Orig, FactMan, JoinLoc, LEK2,
|
|
|
2229 Handler);
|
|
|
2230 if (Modify)
|
|
|
2231 FSet1.removeLock(FactMan, *LDat1);
|
|
|
2232 }
|
|
|
2233 }
|
|
|
2234 }
|
|
|
2235
|
|
|
2236 // Return true if block B never continues to its successors.
|
|
|
2237 static bool neverReturns(const CFGBlock *B) {
|
|
|
2238 if (B->hasNoReturnElement())
|
|
|
2239 return true;
|
|
|
2240 if (B->empty())
|
|
|
2241 return false;
|
|
|
2242
|
|
|
2243 CFGElement Last = B->back();
|
|
|
2244 if (Optional<CFGStmt> S = Last.getAs<CFGStmt>()) {
|
|
|
2245 if (isa<CXXThrowExpr>(S->getStmt()))
|
|
|
2246 return true;
|
|
|
2247 }
|
|
|
2248 return false;
|
|
|
2249 }
|
|
|
2250
|
|
|
2251 /// Check a function's CFG for thread-safety violations.
|
|
|
2252 ///
|
|
|
2253 /// We traverse the blocks in the CFG, compute the set of mutexes that are held
|
|
|
2254 /// at the end of each block, and issue warnings for thread safety violations.
|
|
|
2255 /// Each block in the CFG is traversed exactly once.
|
|
|
2256 void ThreadSafetyAnalyzer::runAnalysis(AnalysisDeclContext &AC) {
|
|
|
2257 // TODO: this whole function needs be rewritten as a visitor for CFGWalker.
|
|
|
2258 // For now, we just use the walker to set things up.
|
|
|
2259 threadSafety::CFGWalker walker;
|
|
|
2260 if (!walker.init(AC))
|
|
|
2261 return;
|
|
|
2262
|
|
|
2263 // AC.dumpCFG(true);
|
|
|
2264 // threadSafety::printSCFG(walker);
|
|
|
2265
|
|
|
2266 CFG *CFGraph = walker.getGraph();
|
|
|
2267 const NamedDecl *D = walker.getDecl();
|
|
|
2268 const auto *CurrentFunction = dyn_cast<FunctionDecl>(D);
|
|
|
2269 CurrentMethod = dyn_cast<CXXMethodDecl>(D);
|
|
|
2270
|
|
|
2271 if (D->hasAttr<NoThreadSafetyAnalysisAttr>())
|
|
|
2272 return;
|
|
|
2273
|
|
|
2274 // FIXME: Do something a bit more intelligent inside constructor and
|
|
|
2275 // destructor code. Constructors and destructors must assume unique access
|
|
|
2276 // to 'this', so checks on member variable access is disabled, but we should
|
|
|
2277 // still enable checks on other objects.
|
|
|
2278 if (isa<CXXConstructorDecl>(D))
|
|
|
2279 return; // Don't check inside constructors.
|
|
|
2280 if (isa<CXXDestructorDecl>(D))
|
|
|
2281 return; // Don't check inside destructors.
|
|
|
2282
|
|
|
2283 Handler.enterFunction(CurrentFunction);
|
|
|
2284
|
|
|
2285 BlockInfo.resize(CFGraph->getNumBlockIDs(),
|
|
|
2286 CFGBlockInfo::getEmptyBlockInfo(LocalVarMap));
|
|
|
2287
|
|
|
2288 // We need to explore the CFG via a "topological" ordering.
|
|
|
2289 // That way, we will be guaranteed to have information about required
|
|
|
2290 // predecessor locksets when exploring a new block.
|
|
|
2291 const PostOrderCFGView *SortedGraph = walker.getSortedGraph();
|
|
|
2292 PostOrderCFGView::CFGBlockSet VisitedBlocks(CFGraph);
|
|
|
2293
|
|
|
2294 // Mark entry block as reachable
|
|
|
2295 BlockInfo[CFGraph->getEntry().getBlockID()].Reachable = true;
|
|
|
2296
|
|
|
2297 // Compute SSA names for local variables
|
|
|
2298 LocalVarMap.traverseCFG(CFGraph, SortedGraph, BlockInfo);
|
|
|
2299
|
|
|
2300 // Fill in source locations for all CFGBlocks.
|
|
|
2301 findBlockLocations(CFGraph, SortedGraph, BlockInfo);
|
|
|
2302
|
|
|
2303 CapExprSet ExclusiveLocksAcquired;
|
|
|
2304 CapExprSet SharedLocksAcquired;
|
|
|
2305 CapExprSet LocksReleased;
|
|
|
2306
|
|
|
2307 // Add locks from exclusive_locks_required and shared_locks_required
|
|
|
2308 // to initial lockset. Also turn off checking for lock and unlock functions.
|
|
|
2309 // FIXME: is there a more intelligent way to check lock/unlock functions?
|
|
|
2310 if (!SortedGraph->empty() && D->hasAttrs()) {
|
|
|
2311 const CFGBlock *FirstBlock = *SortedGraph->begin();
|
|
|
2312 FactSet &InitialLockset = BlockInfo[FirstBlock->getBlockID()].EntrySet;
|
|
|
2313
|
|
|
2314 CapExprSet ExclusiveLocksToAdd;
|
|
|
2315 CapExprSet SharedLocksToAdd;
|
|
|
2316 StringRef CapDiagKind = "mutex";
|
|
|
2317
|
|
|
2318 SourceLocation Loc = D->getLocation();
|
|
|
2319 for (const auto *Attr : D->attrs()) {
|
|
|
2320 Loc = Attr->getLocation();
|
|
|
2321 if (const auto *A = dyn_cast<RequiresCapabilityAttr>(Attr)) {
|
|
|
2322 getMutexIDs(A->isShared() ? SharedLocksToAdd : ExclusiveLocksToAdd, A,
|
|
|
2323 nullptr, D);
|
|
|
2324 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
2325 } else if (const auto *A = dyn_cast<ReleaseCapabilityAttr>(Attr)) {
|
|
|
2326 // UNLOCK_FUNCTION() is used to hide the underlying lock implementation.
|
|
|
2327 // We must ignore such methods.
|
|
|
2328 if (A->args_size() == 0)
|
|
|
2329 return;
|
|
|
2330 getMutexIDs(A->isShared() ? SharedLocksToAdd : ExclusiveLocksToAdd, A,
|
|
|
2331 nullptr, D);
|
|
|
2332 getMutexIDs(LocksReleased, A, nullptr, D);
|
|
|
2333 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
2334 } else if (const auto *A = dyn_cast<AcquireCapabilityAttr>(Attr)) {
|
|
|
2335 if (A->args_size() == 0)
|
|
|
2336 return;
|
|
|
2337 getMutexIDs(A->isShared() ? SharedLocksAcquired
|
|
|
2338 : ExclusiveLocksAcquired,
|
|
|
2339 A, nullptr, D);
|
|
|
2340 CapDiagKind = ClassifyDiagnostic(A);
|
|
|
2341 } else if (isa<ExclusiveTrylockFunctionAttr>(Attr)) {
|
|
|
2342 // Don't try to check trylock functions for now.
|
|
|
2343 return;
|
|
|
2344 } else if (isa<SharedTrylockFunctionAttr>(Attr)) {
|
|
|
2345 // Don't try to check trylock functions for now.
|
|
|
2346 return;
|
|
|
2347 } else if (isa<TryAcquireCapabilityAttr>(Attr)) {
|
|
|
2348 // Don't try to check trylock functions for now.
|
|
|
2349 return;
|
|
|
2350 }
|
|
|
2351 }
|
|
|
2352
|
|
|
2353 // FIXME -- Loc can be wrong here.
|
|
|
2354 for (const auto &Mu : ExclusiveLocksToAdd) {
|
|
|
2355 auto Entry = std::make_unique<LockableFactEntry>(Mu, LK_Exclusive, Loc);
|
|
|
2356 Entry->setDeclared(true);
|
|
|
2357 addLock(InitialLockset, std::move(Entry), CapDiagKind, true);
|
|
|
2358 }
|
|
|
2359 for (const auto &Mu : SharedLocksToAdd) {
|
|
|
2360 auto Entry = std::make_unique<LockableFactEntry>(Mu, LK_Shared, Loc);
|
|
|
2361 Entry->setDeclared(true);
|
|
|
2362 addLock(InitialLockset, std::move(Entry), CapDiagKind, true);
|
|
|
2363 }
|
|
|
2364 }
|
|
|
2365
|
|
|
2366 for (const auto *CurrBlock : *SortedGraph) {
|
|
|
2367 unsigned CurrBlockID = CurrBlock->getBlockID();
|
|
|
2368 CFGBlockInfo *CurrBlockInfo = &BlockInfo[CurrBlockID];
|
|
|
2369
|
|
|
2370 // Use the default initial lockset in case there are no predecessors.
|
|
|
2371 VisitedBlocks.insert(CurrBlock);
|
|
|
2372
|
|
|
2373 // Iterate through the predecessor blocks and warn if the lockset for all
|
|
|
2374 // predecessors is not the same. We take the entry lockset of the current
|
|
|
2375 // block to be the intersection of all previous locksets.
|
|
|
2376 // FIXME: By keeping the intersection, we may output more errors in future
|
|
|
2377 // for a lock which is not in the intersection, but was in the union. We
|
|
|
2378 // may want to also keep the union in future. As an example, let's say
|
|
|
2379 // the intersection contains Mutex L, and the union contains L and M.
|
|
|
2380 // Later we unlock M. At this point, we would output an error because we
|
|
|
2381 // never locked M; although the real error is probably that we forgot to
|
|
|
2382 // lock M on all code paths. Conversely, let's say that later we lock M.
|
|
|
2383 // In this case, we should compare against the intersection instead of the
|
|
|
2384 // union because the real error is probably that we forgot to unlock M on
|
|
|
2385 // all code paths.
|
|
|
2386 bool LocksetInitialized = false;
|
|
|
2387 SmallVector<CFGBlock *, 8> SpecialBlocks;
|
|
|
2388 for (CFGBlock::const_pred_iterator PI = CurrBlock->pred_begin(),
|
|
|
2389 PE = CurrBlock->pred_end(); PI != PE; ++PI) {
|
|
|
2390 // if *PI -> CurrBlock is a back edge
|
|
|
2391 if (*PI == nullptr || !VisitedBlocks.alreadySet(*PI))
|
|
|
2392 continue;
|
|
|
2393
|
|
|
2394 unsigned PrevBlockID = (*PI)->getBlockID();
|
|
|
2395 CFGBlockInfo *PrevBlockInfo = &BlockInfo[PrevBlockID];
|
|
|
2396
|
|
|
2397 // Ignore edges from blocks that can't return.
|
|
|
2398 if (neverReturns(*PI) || !PrevBlockInfo->Reachable)
|
|
|
2399 continue;
|
|
|
2400
|
|
|
2401 // Okay, we can reach this block from the entry.
|
|
|
2402 CurrBlockInfo->Reachable = true;
|
|
|
2403
|
|
|
2404 // If the previous block ended in a 'continue' or 'break' statement, then
|
|
|
2405 // a difference in locksets is probably due to a bug in that block, rather
|
|
|
2406 // than in some other predecessor. In that case, keep the other
|
|
|
2407 // predecessor's lockset.
|
|
|
2408 if (const Stmt *Terminator = (*PI)->getTerminatorStmt()) {
|
|
|
2409 if (isa<ContinueStmt>(Terminator) || isa<BreakStmt>(Terminator)) {
|
|
|
2410 SpecialBlocks.push_back(*PI);
|
|
|
2411 continue;
|
|
|
2412 }
|
|
|
2413 }
|
|
|
2414
|
|
|
2415 FactSet PrevLockset;
|
|
|
2416 getEdgeLockset(PrevLockset, PrevBlockInfo->ExitSet, *PI, CurrBlock);
|
|
|
2417
|
|
|
2418 if (!LocksetInitialized) {
|
|
|
2419 CurrBlockInfo->EntrySet = PrevLockset;
|
|
|
2420 LocksetInitialized = true;
|
|
|
2421 } else {
|
|
|
2422 intersectAndWarn(CurrBlockInfo->EntrySet, PrevLockset,
|
|
|
2423 CurrBlockInfo->EntryLoc,
|
|
|
2424 LEK_LockedSomePredecessors);
|
|
|
2425 }
|
|
|
2426 }
|
|
|
2427
|
|
|
2428 // Skip rest of block if it's not reachable.
|
|
|
2429 if (!CurrBlockInfo->Reachable)
|
|
|
2430 continue;
|
|
|
2431
|
|
|
2432 // Process continue and break blocks. Assume that the lockset for the
|
|
|
2433 // resulting block is unaffected by any discrepancies in them.
|
|
|
2434 for (const auto *PrevBlock : SpecialBlocks) {
|
|
|
2435 unsigned PrevBlockID = PrevBlock->getBlockID();
|
|
|
2436 CFGBlockInfo *PrevBlockInfo = &BlockInfo[PrevBlockID];
|
|
|
2437
|
|
|
2438 if (!LocksetInitialized) {
|
|
|
2439 CurrBlockInfo->EntrySet = PrevBlockInfo->ExitSet;
|
|
|
2440 LocksetInitialized = true;
|
|
|
2441 } else {
|
|
|
2442 // Determine whether this edge is a loop terminator for diagnostic
|
|
|
2443 // purposes. FIXME: A 'break' statement might be a loop terminator, but
|
|
|
2444 // it might also be part of a switch. Also, a subsequent destructor
|
|
|
2445 // might add to the lockset, in which case the real issue might be a
|
|
|
2446 // double lock on the other path.
|
|
|
2447 const Stmt *Terminator = PrevBlock->getTerminatorStmt();
|
|
|
2448 bool IsLoop = Terminator && isa<ContinueStmt>(Terminator);
|
|
|
2449
|
|
|
2450 FactSet PrevLockset;
|
|
|
2451 getEdgeLockset(PrevLockset, PrevBlockInfo->ExitSet,
|
|
|
2452 PrevBlock, CurrBlock);
|
|
|
2453
|
|
|
2454 // Do not update EntrySet.
|
|
|
2455 intersectAndWarn(CurrBlockInfo->EntrySet, PrevLockset,
|
|
|
2456 PrevBlockInfo->ExitLoc,
|
|
|
2457 IsLoop ? LEK_LockedSomeLoopIterations
|
|
|
2458 : LEK_LockedSomePredecessors,
|
|
|
2459 false);
|
|
|
2460 }
|
|
|
2461 }
|
|
|
2462
|
|
|
2463 BuildLockset LocksetBuilder(this, *CurrBlockInfo);
|
|
|
2464
|
|
|
2465 // Visit all the statements in the basic block.
|
|
|
2466 for (const auto &BI : *CurrBlock) {
|
|
|
2467 switch (BI.getKind()) {
|
|
|
2468 case CFGElement::Statement: {
|
|
|
2469 CFGStmt CS = BI.castAs<CFGStmt>();
|
|
|
2470 LocksetBuilder.Visit(CS.getStmt());
|
|
|
2471 break;
|
|
|
2472 }
|
|
|
2473 // Ignore BaseDtor, MemberDtor, and TemporaryDtor for now.
|
|
|
2474 case CFGElement::AutomaticObjectDtor: {
|
|
|
2475 CFGAutomaticObjDtor AD = BI.castAs<CFGAutomaticObjDtor>();
|
|
|
2476 const auto *DD = AD.getDestructorDecl(AC.getASTContext());
|
|
|
2477 if (!DD->hasAttrs())
|
|
|
2478 break;
|
|
|
2479
|
|
|
2480 // Create a dummy expression,
|
|
|
2481 auto *VD = const_cast<VarDecl *>(AD.getVarDecl());
|
|
|
2482 DeclRefExpr DRE(VD->getASTContext(), VD, false,
|
|
|
2483 VD->getType().getNonReferenceType(), VK_LValue,
|
|
|
2484 AD.getTriggerStmt()->getEndLoc());
|
|
|
2485 LocksetBuilder.handleCall(&DRE, DD);
|
|
|
2486 break;
|
|
|
2487 }
|
|
|
2488 default:
|
|
|
2489 break;
|
|
|
2490 }
|
|
|
2491 }
|
|
|
2492 CurrBlockInfo->ExitSet = LocksetBuilder.FSet;
|
|
|
2493
|
|
|
2494 // For every back edge from CurrBlock (the end of the loop) to another block
|
|
|
2495 // (FirstLoopBlock) we need to check that the Lockset of Block is equal to
|
|
|
2496 // the one held at the beginning of FirstLoopBlock. We can look up the
|
|
|
2497 // Lockset held at the beginning of FirstLoopBlock in the EntryLockSets map.
|
|
|
2498 for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(),
|
|
|
2499 SE = CurrBlock->succ_end(); SI != SE; ++SI) {
|
|
|
2500 // if CurrBlock -> *SI is *not* a back edge
|
|
|
2501 if (*SI == nullptr || !VisitedBlocks.alreadySet(*SI))
|
|
|
2502 continue;
|
|
|
2503
|
|
|
2504 CFGBlock *FirstLoopBlock = *SI;
|
|
|
2505 CFGBlockInfo *PreLoop = &BlockInfo[FirstLoopBlock->getBlockID()];
|
|
|
2506 CFGBlockInfo *LoopEnd = &BlockInfo[CurrBlockID];
|
|
|
2507 intersectAndWarn(LoopEnd->ExitSet, PreLoop->EntrySet,
|
|
|
2508 PreLoop->EntryLoc,
|
|
|
2509 LEK_LockedSomeLoopIterations,
|
|
|
2510 false);
|
|
|
2511 }
|
|
|
2512 }
|
|
|
2513
|
|
|
2514 CFGBlockInfo *Initial = &BlockInfo[CFGraph->getEntry().getBlockID()];
|
|
|
2515 CFGBlockInfo *Final = &BlockInfo[CFGraph->getExit().getBlockID()];
|
|
|
2516
|
|
|
2517 // Skip the final check if the exit block is unreachable.
|
|
|
2518 if (!Final->Reachable)
|
|
|
2519 return;
|
|
|
2520
|
|
|
2521 // By default, we expect all locks held on entry to be held on exit.
|
|
|
2522 FactSet ExpectedExitSet = Initial->EntrySet;
|
|
|
2523
|
|
|
2524 // Adjust the expected exit set by adding or removing locks, as declared
|
|
|
2525 // by *-LOCK_FUNCTION and UNLOCK_FUNCTION. The intersect below will then
|
|
|
2526 // issue the appropriate warning.
|
|
|
2527 // FIXME: the location here is not quite right.
|
|
|
2528 for (const auto &Lock : ExclusiveLocksAcquired)
|
|
|
2529 ExpectedExitSet.addLock(FactMan, std::make_unique<LockableFactEntry>(
|
|
|
2530 Lock, LK_Exclusive, D->getLocation()));
|
|
|
2531 for (const auto &Lock : SharedLocksAcquired)
|
|
|
2532 ExpectedExitSet.addLock(FactMan, std::make_unique<LockableFactEntry>(
|
|
|
2533 Lock, LK_Shared, D->getLocation()));
|
|
|
2534 for (const auto &Lock : LocksReleased)
|
|
|
2535 ExpectedExitSet.removeLock(FactMan, Lock);
|
|
|
2536
|
|
|
2537 // FIXME: Should we call this function for all blocks which exit the function?
|
|
|
2538 intersectAndWarn(ExpectedExitSet, Final->ExitSet,
|
|
|
2539 Final->ExitLoc,
|
|
|
2540 LEK_LockedAtEndOfFunction,
|
|
|
2541 LEK_NotLockedAtEndOfFunction,
|
|
|
2542 false);
|
|
|
2543
|
|
|
2544 Handler.leaveFunction(CurrentFunction);
|
|
|
2545 }
|
|
|
2546
|
|
|
2547 /// Check a function's CFG for thread-safety violations.
|
|
|
2548 ///
|
|
|
2549 /// We traverse the blocks in the CFG, compute the set of mutexes that are held
|
|
|
2550 /// at the end of each block, and issue warnings for thread safety violations.
|
|
|
2551 /// Each block in the CFG is traversed exactly once.
|
|
|
2552 void threadSafety::runThreadSafetyAnalysis(AnalysisDeclContext &AC,
|
|
|
2553 ThreadSafetyHandler &Handler,
|
|
|
2554 BeforeSet **BSet) {
|
|
|
2555 if (!*BSet)
|
|
|
2556 *BSet = new BeforeSet;
|
|
|
2557 ThreadSafetyAnalyzer Analyzer(Handler, *BSet);
|
|
|
2558 Analyzer.runAnalysis(AC);
|
|
|
2559 }
|
|
|
2560
|
|
|
2561 void threadSafety::threadSafetyCleanup(BeforeSet *Cache) { delete Cache; }
|
|
|
2562
|
|
|
2563 /// Helper function that returns a LockKind required for the given level
|
|
|
2564 /// of access.
|
|
|
2565 LockKind threadSafety::getLockKindFromAccessKind(AccessKind AK) {
|
|
|
2566 switch (AK) {
|
|
|
2567 case AK_Read :
|
|
|
2568 return LK_Shared;
|
|
|
2569 case AK_Written :
|
|
|
2570 return LK_Exclusive;
|
|
|
2571 }
|
|
|
2572 llvm_unreachable("Unknown AccessKind");
|
|
|
2573 }
|
