Utilities/StaticAnalyzers/src/TrunCastChecker.cpp - master - githubmirror/cmssw

Utilities/StaticAnalyzers/src/TrunCastChecker.cpp
215 строк9 KB
Shahzad Malik Muzaffar
sync back llvm10 changes
25 май 2020, 09:57
25 май 2020, 09:57df26429
#include <clang/AST/Attr.h>
#include <clang/AST/DeclCXX.h>
#include <clang/AST/ExprCXX.h>
#include <clang/AST/Expr.h>
#include <clang/AST/Decl.h>
#include <clang/AST/DeclTemplate.h>
#include <clang/AST/StmtVisitor.h>
#include <clang/AST/ParentMap.h>
#include <clang/Analysis/CFGStmtMap.h>
#include <clang/Analysis/CallGraph.h>
#include <llvm/Support/SaveAndRestore.h>
#include <clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h>
#include <clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h>
#include <clang/StaticAnalyzer/Core/Checker.h>
#include <clang/StaticAnalyzer/Core/BugReporter/BugReporter.h>
#include <clang/StaticAnalyzer/Core/BugReporter/BugType.h>
#include <llvm/ADT/SmallString.h>
#include "TrunCastChecker.h"
#include "CmsSupport.h"

using namespace clang;
using namespace ento;
using namespace llvm;

namespace clangcms {

  class ICEVisitor : public clang::StmtVisitor<ICEVisitor> {
    const clang::ento::CheckerBase *Checker;
    clang::ento::BugReporter &BR;
    clang::AnalysisDeclContext *AC;

  public:
    ICEVisitor(const clang::ento::CheckerBase *checker, clang::ento::BugReporter &br, clang::AnalysisDeclContext *ac)
        : Checker(checker), BR(br), AC(ac) {}

    void VisitImplicitCastExpr(ImplicitCastExpr *CE);
    void VisitBinaryOperator(BinaryOperator *BO);
    void VisitChildren(clang::Stmt *S);
    void VisitStmt(clang::Stmt *S) { VisitChildren(S); }
  };

  void ICEVisitor::VisitChildren(clang::Stmt *S) {
    for (auto I = S->child_begin(), E = S->child_end(); I != E; ++I)
      if (clang::Stmt *child = *I) {
        Visit(child);
      }
  }

  void ICEVisitor::VisitBinaryOperator(BinaryOperator *BO) {
    const NamedDecl *ACD = dyn_cast_or_null<NamedDecl>(AC->getDecl());
    VisitChildren(BO);
    std::string ename = "EventNumber_t";
    clang::Expr *LHS = BO->getLHS();
    clang::Expr *RHS = BO->getRHS();
    if (!LHS || !RHS)
      return;
    std::string lname = LHS->getType().getAsString();
    std::string rname = RHS->getType().getAsString();
    if (IntegerLiteral::classof(LHS->IgnoreCasts()) || IntegerLiteral::classof(RHS->IgnoreCasts()))
      return;
    if (!(lname == ename || rname == ename))
      return;
    if (lname == ename && rname == ename)
      return;
    clang::QualType OTy;
    clang::QualType TTy;
    if (lname == ename && ImplicitCastExpr::classof(RHS)) {
      ImplicitCastExpr *ICE = dyn_cast_or_null<ImplicitCastExpr>(RHS);
      TTy = BR.getContext().getCanonicalType(LHS->getType());
      OTy = BR.getContext().getCanonicalType(ICE->getSubExprAsWritten()->getType());
    }
    if (rname == ename && ImplicitCastExpr::classof(LHS)) {
      ImplicitCastExpr *ICE = dyn_cast_or_null<ImplicitCastExpr>(LHS);
      TTy = BR.getContext().getCanonicalType(RHS->getType());
      OTy = BR.getContext().getCanonicalType(ICE->getSubExprAsWritten()->getType());
    }
    if (TTy.isNull() || OTy.isNull())
      return;
    QualType ToTy = TTy.getUnqualifiedType();
    QualType OrigTy = OTy.getUnqualifiedType();
    if (!(ToTy->isIntegerType() || ToTy->isFloatingType()))
      return;
    if (ToTy->isBooleanType())
      return;
    CharUnits size_otype = BR.getContext().getTypeSizeInChars(OrigTy);
    CharUnits size_ttype = BR.getContext().getTypeSizeInChars(ToTy);
    std::string oname = OrigTy.getAsString();
    std::string tname = ToTy.getAsString();
    if (ToTy->isFloatingType()) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << " . " << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(BO, BR.getSourceManager(), AC);
      BR.EmitBasicReport(ACD,
                         CheckerNameRef(),
                         "implicit cast of int type to float type",
                         "CMS code rules",
                         os.str(),
                         CELoc,
                         BO->getSourceRange());
    }
    if ((size_otype > size_ttype)) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << ". Cast may result in truncation. "
         << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(BO, BR.getSourceManager(), AC);
      BR.EmitBasicReport(ACD,
                         CheckerNameRef(),
                         "implicit cast of int type to smaller int type could truncate",
                         "CMS code rules",
                         os.str(),
                         CELoc,
                         BO->getSourceRange());
    }
    if ((size_otype == size_ttype) &&
        (ToTy->hasSignedIntegerRepresentation() && OrigTy->hasUnsignedIntegerRepresentation() ||
         ToTy->hasUnsignedIntegerRepresentation() && OrigTy->hasSignedIntegerRepresentation())) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << ". Changes int sign type. "
         << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(BO, BR.getSourceManager(), AC);
      BR.EmitBasicReport(
          ACD, CheckerNameRef(), "implicit cast ins sign type", "CMS code rules", os.str(), CELoc, BO->getSourceRange());
    }
    return;
    return;
  }

  void ICEVisitor::VisitImplicitCastExpr(ImplicitCastExpr *CE) {
    const NamedDecl *ACD = dyn_cast<NamedDecl>(AC->getDecl());
    VisitChildren(CE);
    const Expr *SE = CE->getSubExprAsWritten();
    std::string sename = SE->getType().getAsString();
    const clang::Expr *E = CE->getSubExpr();
    if (!(sename == "EventNumber_t"))
      return;
    QualType OTy = BR.getContext().getCanonicalType(E->getType());
    QualType TTy = BR.getContext().getCanonicalType(CE->getType());
    QualType ToTy = TTy.getUnqualifiedType();
    QualType OrigTy = OTy.getUnqualifiedType();
    if (!(ToTy->isIntegerType() || ToTy->isFloatingType()))
      return;
    if (ToTy->isBooleanType())
      return;
    CharUnits size_otype = BR.getContext().getTypeSizeInChars(OrigTy);
    CharUnits size_ttype = BR.getContext().getTypeSizeInChars(ToTy);
    std::string oname = OrigTy.getAsString();
    std::string tname = ToTy.getAsString();
    if (ToTy->isFloatingType()) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << " . " << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(CE, BR.getSourceManager(), AC);
      BR.EmitBasicReport(ACD,
                         CheckerNameRef(),
                         "implicit cast of int type to float type",
                         "CMS code rules",
                         os.str(),
                         CELoc,
                         CE->getSourceRange());
    }
    if ((size_otype > size_ttype)) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << ". Cast may result in truncation. "
         << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(CE, BR.getSourceManager(), AC);
      BR.EmitBasicReport(ACD,
                         CheckerNameRef(),
                         "implicit cast of int type to smaller int type could truncate",
                         "CMS code rules",
                         os.str(),
                         CELoc,
                         CE->getSourceRange());
    }
    if (ToTy->hasSignedIntegerRepresentation() && OrigTy->hasUnsignedIntegerRepresentation() ||
        ToTy->hasUnsignedIntegerRepresentation() && OrigTy->hasSignedIntegerRepresentation()) {
      llvm::SmallString<100> buf;
      llvm::raw_svector_ostream os(buf);
      os << "Cast-to type, " << tname << ". Cast-from type, " << oname << ". Changes int sign type. "
         << support::getQualifiedName(*(ACD));
      clang::ento::PathDiagnosticLocation CELoc =
          clang::ento::PathDiagnosticLocation::createBegin(CE, BR.getSourceManager(), AC);
      BR.EmitBasicReport(ACD,
                         CheckerNameRef(),
                         "implicit cast changes int sign type",
                         "CMS code rules",
                         os.str(),
                         CELoc,
                         CE->getSourceRange());
    }
    return;
  }

  void TrunCastChecker::checkASTDecl(const CXXRecordDecl *D, AnalysisManager &Mgr, BugReporter &BR) const {
    for (auto I = D->method_begin(), E = D->method_end(); I != E; ++I) {
      if (!llvm::isa<clang::CXXMethodDecl>((*I)))
        continue;
      clang::CXXMethodDecl *MD = llvm::cast<clang::CXXMethodDecl>((*I)->getMostRecentDecl());
      if (!MD->hasBody())
        continue;
      clang::Stmt *Body = MD->getBody();
      ICEVisitor icevisitor(this, BR, Mgr.getAnalysisDeclContext(MD));
      icevisitor.Visit(Body);
    }
  }

}  // namespace clangcms