File indexing completed on 2024-04-28 16:57:53

 /*
     This file is part of the clazy static checker.
 
     Copyright (C) 2016-2017 Sergio Martins <smartins@kde.org>
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
 
     This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Library General Public License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to
     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
 */
 
 #ifndef CLAZY_TYPE_UTILS_H
 #define CLAZY_TYPE_UTILS_H
 
 #include <clang/AST/Type.h>
 #include <clang/AST/Expr.h>
 #include <clang/AST/StmtCXX.h>
 #include <clang/AST/DeclCXX.h>
 #include <clang/AST/ASTContext.h>
 #include <clang/AST/Decl.h>
 #include <llvm/Support/Casting.h>
 
 #include <string>
 #include <vector>
 
 namespace clang {
 class CompilerInstance;
 class Expr;
 class LangOptions;
 class QualType;
 class Stmt;
 class VarDecl;
 class Type;
 class CXXRecordDecl;
 class CXXBaseSpecifier;
 }
 
 class ClazyContext;
 
 namespace clazy
 {
 /**
  * Returns the sizeof(void*) for the platform we're compiling for, in bits.
  */
 inline int sizeOfPointer(const clang::ASTContext *context, clang::QualType qt)
 {
     if (!qt.getTypePtrOrNull())
         return -1;
     // HACK: What's a better way of getting the size of a pointer ?
     return context->getTypeSize(context->getPointerType(qt));
 }
 
 struct QualTypeClassification {
     bool isConst = false;
     bool isReference = false;
     bool isBig = false;
     bool isNonTriviallyCopyable = false;
     bool passBigTypeByConstRef = false;
     bool passNonTriviallyCopyableByConstRef = false;
     bool passSmallTrivialByValue = false;
     int size_of_T = 0;
 };
 
 /**
  * Classifies a QualType, for example:
  *
  * This function is useful to know if a type should be passed by value or const-ref.
  * The optional parameter body is in order to advise non-const-ref -> value, since the body
  * needs to be inspected to see if we that would compile.
  */
 bool classifyQualType(const ClazyContext *context, clang::QualType qualType, const clang::VarDecl *varDecl,
                       QualTypeClassification &classification,
                       clang::Stmt *body = nullptr);
 
 /**
  * @brief Lighter version of classifyQualType in case you just want to know if it's small and trivially copyable&destructible
  * @param context The clazy context
  * @param qualType The QualType we're testing.
  * @return true if the type specified by QualType (or its pointee) are small and trivially copyable/destructible.
  */
 bool isSmallTrivial(const ClazyContext *context, clang::QualType qualType);
 
 /**
  * If qt is a reference, return it without a reference.
  * If qt is not a reference, return qt.
  *
  * This is useful because sometimes you have an argument like "const QString &", but qualType.isConstQualified()
  * returns false. Must go through qualType->getPointeeType().isConstQualified().
  */
 inline clang::QualType unrefQualType(clang::QualType qualType)
 {
     const clang::Type *t = qualType.getTypePtrOrNull();
     return (t && t->isReferenceType()) ? t->getPointeeType() : qualType;
 }
 
 /**
  * If qt is a pointer or ref, return it without * or &.
  * Otherwise return qt unchanged.
  */
 inline clang::QualType pointeeQualType(clang::QualType qualType)
 {
     // TODO: Make this recursive when we need to remove more than one level of *
     const clang::Type *t = qualType.getTypePtrOrNull();
     return (t && (t->isReferenceType() || t->isPointerType())) ? t->getPointeeType() : qualType;
 }
 
 /**
  * Returns if @p arg is stack or heap allocated.
  * true means it is. false means it either isn't or the situation was too complex to judge.
  */
 void heapOrStackAllocated(clang::Expr *arg, const std::string &type,
                           const clang::LangOptions &lo,
                           bool &isStack, bool &isHeap);
 
 /**
  * Returns true if t is an AutoType that can't be deduced.
  */
 inline bool isUndeducibleAuto(const clang::Type *t)
 {
     if (!t)
         return false;
 
     auto at = llvm::dyn_cast<clang::AutoType>(t);
     return at && at->getDeducedType().isNull();
 }
 
 inline const clang::Type * unpealAuto(clang::QualType q)
 {
     if (q.isNull())
         return nullptr;
 
     if (auto t = llvm::dyn_cast<clang::AutoType>(q.getTypePtr()))
         return t->getDeducedType().getTypePtrOrNull();
 
     return q.getTypePtr();
 }
 
 /**
  * Returns true if childDecl is a descent from parentDecl
  **/
 bool derivesFrom(const clang::CXXRecordDecl *derived, const clang::CXXRecordDecl *possibleBase,
                  std::vector<clang::CXXRecordDecl*> *baseClasses = nullptr);
 
 // Overload
 bool derivesFrom(const clang::CXXRecordDecl *derived, const std::string &possibleBase);
 
 // Overload
 bool derivesFrom(clang::QualType derived, const std::string &possibleBase);
 
 /**
  * Returns the CXXRecordDecl represented by the CXXBaseSpecifier
  */
 inline clang::CXXRecordDecl * recordFromBaseSpecifier(const clang::CXXBaseSpecifier &base)
 {
     const clang::Type *t = base.getType().getTypePtrOrNull();
     return t ? t->getAsCXXRecordDecl() : nullptr;
 }
 /**
  * Returns true if the value is const. This is usually equivalent to qt.isConstQualified() but
  * takes care of the special case where qt represents a pointer. Many times you don't care if the
  * pointer is const or not and just care about the pointee.
  *
  * A a;        => false
  * const A a;  => true
  * A* a;       => false
  * const A* a; => true
  * A *const a; => false
  */
 inline bool valueIsConst(clang::QualType qt)
 {
     return pointeeQualType(qt).isConstQualified();
 }
 
 inline clang::CXXRecordDecl* typeAsRecord(clang::QualType qt)
 {
     if (qt.isNull())
         return nullptr;
 
     return qt->getAsCXXRecordDecl();
 }
 
 inline clang::CXXRecordDecl* typeAsRecord(clang::Expr *expr)
 {
     if (!expr)
         return nullptr;
 
     return typeAsRecord(pointeeQualType(expr->getType()));
 }
 
 inline clang::CXXRecordDecl* typeAsRecord(clang::ValueDecl *value)
 {
     if (!value)
         return nullptr;
 
     return typeAsRecord(pointeeQualType(value->getType()));
 }
 
 /**
  * Returns the class that the typedef refered by qt is in.
  *
  * class Foo {
  *     typedef A B;
  * };
  *
  * For the above example Foo would be returned.
  */
 inline clang::CXXRecordDecl* parentRecordForTypedef(clang::QualType qt)
 {
     auto t = qt.getTypePtrOrNull();
     if (!t)
         return nullptr;
 
     if (t->getTypeClass() == clang::Type::Typedef) {
         auto tdt = static_cast<const clang::TypedefType*>(t);
         clang::TypedefNameDecl *tdnd = tdt->getDecl();
         return llvm::dyn_cast_or_null<clang::CXXRecordDecl>(tdnd->getDeclContext());
 
     }
 
     return nullptr;
 }
 
 // Example: const QString &
 inline bool isConstRef(const clang::Type *t)
 {
     return t && t->isReferenceType() && t->getPointeeType().isConstQualified();
 }
 }
 
 #endif