NoReturnFunctionChecker.cpp revision 9b663716449b618ba0390b1dbebc54fa8e971124 
1//=== NoReturnFunctionChecker.cpp -------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This defines NoReturnFunctionChecker, which evaluates functions that do not
11// return to the caller.
12//
13//===----------------------------------------------------------------------===//
14
15#include "InternalChecks.h"
16#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerVisitor.h"
17#include "llvm/ADT/StringSwitch.h"
18
19using namespace clang;
20using namespace ento;
21
22namespace {
23
24class NoReturnFunctionChecker : public CheckerVisitor<NoReturnFunctionChecker> {
25public:
26  static void *getTag() { static int tag = 0; return &tag; }
27  void PostVisitCallExpr(CheckerContext &C, const CallExpr *CE);
28};
29
30}
31
32void ento::RegisterNoReturnFunctionChecker(ExprEngine &Eng) {
33  Eng.registerCheck(new NoReturnFunctionChecker());
34}
35
36void NoReturnFunctionChecker::PostVisitCallExpr(CheckerContext &C,
37                                                const CallExpr *CE) {
38  const GRState *state = C.getState();
39  const Expr *Callee = CE->getCallee();
40
41  bool BuildSinks = getFunctionExtInfo(Callee->getType()).getNoReturn();
42
43  if (!BuildSinks) {
44    SVal L = state->getSVal(Callee);
45    const FunctionDecl *FD = L.getAsFunctionDecl();
46    if (!FD)
47      return;
48
49    if (FD->getAttr<AnalyzerNoReturnAttr>())
50      BuildSinks = true;
51    else if (const IdentifierInfo *II = FD->getIdentifier()) {
52      // HACK: Some functions are not marked noreturn, and don't return.
53      //  Here are a few hardwired ones.  If this takes too long, we can
54      //  potentially cache these results.
55      BuildSinks
56        = llvm::StringSwitch<bool>(llvm::StringRef(II->getName()))
57            .Case("exit", true)
58            .Case("panic", true)
59            .Case("error", true)
60            .Case("Assert", true)
61            // FIXME: This is just a wrapper around throwing an exception.
62            //  Eventually inter-procedural analysis should handle this easily.
63            .Case("ziperr", true)
64            .Case("assfail", true)
65            .Case("db_error", true)
66            .Case("__assert", true)
67            .Case("__assert_rtn", true)
68            .Case("__assert_fail", true)
69            .Case("dtrace_assfail", true)
70            .Case("yy_fatal_error", true)
71            .Case("_XCAssertionFailureHandler", true)
72            .Case("_DTAssertionFailureHandler", true)
73            .Case("_TSAssertionFailureHandler", true)
74            .Default(false);
75    }
76  }
77
78  if (BuildSinks)
79    C.generateSink(CE);
80}
81