1 //== CheckerContext.cpp - Context info for path-sensitive checkers-----------=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines CheckerContext that provides contextual info for
11 // path-sensitive checkers.
13 //===----------------------------------------------------------------------===//
15 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
16 #include "clang/Basic/Builtins.h"
17 #include "clang/Lex/Lexer.h"
19 using namespace clang;
22 const FunctionDecl *CheckerContext::getCalleeDecl(const CallExpr *CE) const {
23 ProgramStateRef State = getState();
24 const Expr *Callee = CE->getCallee();
25 SVal L = State->getSVal(Callee, Pred->getLocationContext());
26 return L.getAsFunctionDecl();
29 StringRef CheckerContext::getCalleeName(const FunctionDecl *FunDecl) const {
32 IdentifierInfo *funI = FunDecl->getIdentifier();
35 return funI->getName();
38 StringRef CheckerContext::getDeclDescription(const Decl *D) {
39 if (isa<ObjCMethodDecl>(D) || isa<CXXMethodDecl>(D))
41 if (isa<BlockDecl>(D))
42 return "anonymous block";
46 bool CheckerContext::isCLibraryFunction(const FunctionDecl *FD,
48 // To avoid false positives (Ex: finding user defined functions with
49 // similar names), only perform fuzzy name matching when it's a builtin.
50 // Using a string compare is slow, we might want to switch on BuiltinID here.
51 unsigned BId = FD->getBuiltinID();
55 StringRef BName = FD->getASTContext().BuiltinInfo.getName(BId);
56 if (BName.find(Name) != StringRef::npos)
60 const IdentifierInfo *II = FD->getIdentifier();
61 // If this is a special C++ name without IdentifierInfo, it can't be a
62 // C library function.
66 // Look through 'extern "C"' and anything similar invented in the future.
67 // If this function is not in TU directly, it is not a C library function.
68 if (!FD->getDeclContext()->getRedeclContext()->isTranslationUnit())
71 // If this function is not externally visible, it is not a C library function.
72 // Note that we make an exception for inline functions, which may be
73 // declared in header files without external linkage.
74 if (!FD->isInlined() && !FD->isExternallyVisible())
80 StringRef FName = II->getName();
81 if (FName.equals(Name))
84 if (FName.startswith("__inline") && (FName.find(Name) != StringRef::npos))
87 if (FName.startswith("__") && FName.endswith("_chk") &&
88 FName.find(Name) != StringRef::npos)
94 StringRef CheckerContext::getMacroNameOrSpelling(SourceLocation &Loc) {
96 return Lexer::getImmediateMacroName(Loc, getSourceManager(),
98 SmallVector<char, 16> buf;
99 return Lexer::getSpelling(Loc, buf, getSourceManager(), getLangOpts());
102 /// Evaluate comparison and return true if it's known that condition is true
103 static bool evalComparison(SVal LHSVal, BinaryOperatorKind ComparisonOp,
104 SVal RHSVal, ProgramStateRef State) {
105 if (LHSVal.isUnknownOrUndef())
107 ProgramStateManager &Mgr = State->getStateManager();
108 if (!LHSVal.getAs<NonLoc>()) {
109 LHSVal = Mgr.getStoreManager().getBinding(State->getStore(),
110 LHSVal.castAs<Loc>());
111 if (LHSVal.isUnknownOrUndef() || !LHSVal.getAs<NonLoc>())
115 SValBuilder &Bldr = Mgr.getSValBuilder();
116 SVal Eval = Bldr.evalBinOp(State, ComparisonOp, LHSVal, RHSVal,
117 Bldr.getConditionType());
118 if (Eval.isUnknownOrUndef())
120 ProgramStateRef StTrue, StFalse;
121 std::tie(StTrue, StFalse) = State->assume(Eval.castAs<DefinedSVal>());
122 return StTrue && !StFalse;
125 bool CheckerContext::isGreaterOrEqual(const Expr *E, unsigned long long Val) {
126 DefinedSVal V = getSValBuilder().makeIntVal(Val, getASTContext().LongLongTy);
127 return evalComparison(getSVal(E), BO_GE, V, getState());
130 bool CheckerContext::isNegative(const Expr *E) {
131 DefinedSVal V = getSValBuilder().makeIntVal(0, false);
132 return evalComparison(getSVal(E), BO_LT, V, getState());