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author | 2020-08-03 14:31:31 +0000 | |
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committer | 2020-08-03 14:31:31 +0000 | |
commit | e5dd70708596ae51455a0ffa086a00c5b29f8583 (patch) | |
tree | 5d676f27b570bacf71e786c3b5cff3e6f6679b59 /gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp | |
parent | Import LLVM 10.0.0 release including clang, lld and lldb. (diff) | |
download | wireguard-openbsd-e5dd70708596ae51455a0ffa086a00c5b29f8583.tar.xz wireguard-openbsd-e5dd70708596ae51455a0ffa086a00c5b29f8583.zip |
Import LLVM 10.0.0 release including clang, lld and lldb.
ok hackroom
tested by plenty
Diffstat (limited to 'gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp')
-rw-r--r-- | gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp b/gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp new file mode 100644 index 00000000000..725ff1002e2 --- /dev/null +++ b/gnu/llvm/clang/lib/StaticAnalyzer/Core/CheckerContext.cpp @@ -0,0 +1,131 @@ +//== CheckerContext.cpp - Context info for path-sensitive checkers-----------=// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file defines CheckerContext that provides contextual info for +// path-sensitive checkers. +// +//===----------------------------------------------------------------------===// + +#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" +#include "clang/Basic/Builtins.h" +#include "clang/Lex/Lexer.h" + +using namespace clang; +using namespace ento; + +const FunctionDecl *CheckerContext::getCalleeDecl(const CallExpr *CE) const { + const Expr *Callee = CE->getCallee(); + SVal L = Pred->getSVal(Callee); + return L.getAsFunctionDecl(); +} + +StringRef CheckerContext::getCalleeName(const FunctionDecl *FunDecl) const { + if (!FunDecl) + return StringRef(); + IdentifierInfo *funI = FunDecl->getIdentifier(); + if (!funI) + return StringRef(); + return funI->getName(); +} + +StringRef CheckerContext::getDeclDescription(const Decl *D) { + if (isa<ObjCMethodDecl>(D) || isa<CXXMethodDecl>(D)) + return "method"; + if (isa<BlockDecl>(D)) + return "anonymous block"; + return "function"; +} + +bool CheckerContext::isCLibraryFunction(const FunctionDecl *FD, + StringRef Name) { + // To avoid false positives (Ex: finding user defined functions with + // similar names), only perform fuzzy name matching when it's a builtin. + // Using a string compare is slow, we might want to switch on BuiltinID here. + unsigned BId = FD->getBuiltinID(); + if (BId != 0) { + if (Name.empty()) + return true; + StringRef BName = FD->getASTContext().BuiltinInfo.getName(BId); + if (BName.find(Name) != StringRef::npos) + return true; + } + + const IdentifierInfo *II = FD->getIdentifier(); + // If this is a special C++ name without IdentifierInfo, it can't be a + // C library function. + if (!II) + return false; + + // Look through 'extern "C"' and anything similar invented in the future. + // If this function is not in TU directly, it is not a C library function. + if (!FD->getDeclContext()->getRedeclContext()->isTranslationUnit()) + return false; + + // If this function is not externally visible, it is not a C library function. + // Note that we make an exception for inline functions, which may be + // declared in header files without external linkage. + if (!FD->isInlined() && !FD->isExternallyVisible()) + return false; + + if (Name.empty()) + return true; + + StringRef FName = II->getName(); + if (FName.equals(Name)) + return true; + + if (FName.startswith("__inline") && (FName.find(Name) != StringRef::npos)) + return true; + + if (FName.startswith("__") && FName.endswith("_chk") && + FName.find(Name) != StringRef::npos) + return true; + + return false; +} + +StringRef CheckerContext::getMacroNameOrSpelling(SourceLocation &Loc) { + if (Loc.isMacroID()) + return Lexer::getImmediateMacroName(Loc, getSourceManager(), + getLangOpts()); + SmallVector<char, 16> buf; + return Lexer::getSpelling(Loc, buf, getSourceManager(), getLangOpts()); +} + +/// Evaluate comparison and return true if it's known that condition is true +static bool evalComparison(SVal LHSVal, BinaryOperatorKind ComparisonOp, + SVal RHSVal, ProgramStateRef State) { + if (LHSVal.isUnknownOrUndef()) + return false; + ProgramStateManager &Mgr = State->getStateManager(); + if (!LHSVal.getAs<NonLoc>()) { + LHSVal = Mgr.getStoreManager().getBinding(State->getStore(), + LHSVal.castAs<Loc>()); + if (LHSVal.isUnknownOrUndef() || !LHSVal.getAs<NonLoc>()) + return false; + } + + SValBuilder &Bldr = Mgr.getSValBuilder(); + SVal Eval = Bldr.evalBinOp(State, ComparisonOp, LHSVal, RHSVal, + Bldr.getConditionType()); + if (Eval.isUnknownOrUndef()) + return false; + ProgramStateRef StTrue, StFalse; + std::tie(StTrue, StFalse) = State->assume(Eval.castAs<DefinedSVal>()); + return StTrue && !StFalse; +} + +bool CheckerContext::isGreaterOrEqual(const Expr *E, unsigned long long Val) { + DefinedSVal V = getSValBuilder().makeIntVal(Val, getASTContext().LongLongTy); + return evalComparison(getSVal(E), BO_GE, V, getState()); +} + +bool CheckerContext::isNegative(const Expr *E) { + DefinedSVal V = getSValBuilder().makeIntVal(0, false); + return evalComparison(getSVal(E), BO_LT, V, getState()); +} |