clang/lib/ARCMigrate/Transforms.h

   1 //===-- Transforms.h - Transformations to ARC mode --------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_CLANG_LIB_ARCMIGRATE_TRANSFORMS_H
  10 #define LLVM_CLANG_LIB_ARCMIGRATE_TRANSFORMS_H
  11
  12 #include "clang/AST/ParentMap.h"
  13 #include "clang/AST/RecursiveASTVisitor.h"
  14 #include "llvm/ADT/DenseSet.h"
  15 #include "llvm/Support/SaveAndRestore.h"
  16
  17 namespace clang {
  18   class Decl;
  19   class Stmt;
  20   class BlockDecl;
  21   class ObjCMethodDecl;
  22   class FunctionDecl;
  23
  24 namespace arcmt {
  25   class MigrationPass;
  26
  27 namespace trans {
  28
  29   class MigrationContext;
  30
  31 //===----------------------------------------------------------------------===//
  32 // Transformations.
  33 //===----------------------------------------------------------------------===//
  34
  35 void rewriteAutoreleasePool(MigrationPass &pass);
  36 void rewriteUnbridgedCasts(MigrationPass &pass);
  37 void makeAssignARCSafe(MigrationPass &pass);
  38 void removeRetainReleaseDeallocFinalize(MigrationPass &pass);
  39 void removeZeroOutPropsInDeallocFinalize(MigrationPass &pass);
  40 void rewriteUnusedInitDelegate(MigrationPass &pass);
  41 void checkAPIUses(MigrationPass &pass);
  42
  43 void removeEmptyStatementsAndDeallocFinalize(MigrationPass &pass);
  44
  45 class BodyContext {
  46   MigrationContext &MigrateCtx;
  47   ParentMap PMap;
  48   Stmt *TopStmt;
  49
  50 public:
  51   BodyContext(MigrationContext &MigrateCtx, Stmt *S)
  52     : MigrateCtx(MigrateCtx), PMap(S), TopStmt(S) {}
  53
  54   MigrationContext &getMigrationContext() { return MigrateCtx; }
  55   ParentMap &getParentMap() { return PMap; }
  56   Stmt *getTopStmt() { return TopStmt; }
  57 };
  58
  59 class ObjCImplementationContext {
  60   MigrationContext &MigrateCtx;
  61   ObjCImplementationDecl *ImpD;
  62
  63 public:
  64   ObjCImplementationContext(MigrationContext &MigrateCtx,
  65                             ObjCImplementationDecl *D)
  66     : MigrateCtx(MigrateCtx), ImpD(D) {}
  67
  68   MigrationContext &getMigrationContext() { return MigrateCtx; }
  69   ObjCImplementationDecl *getImplementationDecl() { return ImpD; }
  70 };
  71
  72 class ASTTraverser {
  73 public:
  74   virtual ~ASTTraverser();
  75   virtual void traverseTU(MigrationContext &MigrateCtx) { }
  76   virtual void traverseBody(BodyContext &BodyCtx) { }
  77   virtual void traverseObjCImplementation(ObjCImplementationContext &ImplCtx) {}
  78 };
  79
  80 class MigrationContext {
  81   std::vector<ASTTraverser *> Traversers;
  82
  83 public:
  84   MigrationPass &Pass;
  85
  86   struct GCAttrOccurrence {
  87     enum AttrKind { Weak, Strong } Kind;
  88     SourceLocation Loc;
  89     QualType ModifiedType;
  90     Decl *Dcl;
  91     /// true if the attribute is owned, e.g. it is in a body and not just
  92     /// in an interface.
  93     bool FullyMigratable;
  94   };
  95   std::vector<GCAttrOccurrence> GCAttrs;
  96   llvm::DenseSet<SourceLocation> AttrSet;
  97   llvm::DenseSet<SourceLocation> RemovedAttrSet;
  98
  99   /// Set of raw '@' locations for 'assign' properties group that contain
 100   /// GC __weak.
 101   llvm::DenseSet<SourceLocation> AtPropsWeak;
 102
 103   explicit MigrationContext(MigrationPass &pass) : Pass(pass) {}
 104   ~MigrationContext();
 105
 106   typedef std::vector<ASTTraverser *>::iterator traverser_iterator;
 107   traverser_iterator traversers_begin() { return Traversers.begin(); }
 108   traverser_iterator traversers_end() { return Traversers.end(); }
 109
 110   void addTraverser(ASTTraverser *traverser) {
 111     Traversers.push_back(traverser);
 112   }
 113
 114   bool isGCOwnedNonObjC(QualType T);
 115   bool removePropertyAttribute(StringRef fromAttr, SourceLocation atLoc) {
 116     return rewritePropertyAttribute(fromAttr, StringRef(), atLoc);
 117   }
 118   bool rewritePropertyAttribute(StringRef fromAttr, StringRef toAttr,
 119                                 SourceLocation atLoc);
 120   bool addPropertyAttribute(StringRef attr, SourceLocation atLoc);
 121
 122   void traverse(TranslationUnitDecl *TU);
 123
 124   void dumpGCAttrs();
 125 };
 126
 127 class PropertyRewriteTraverser : public ASTTraverser {
 128 public:
 129   void traverseObjCImplementation(ObjCImplementationContext &ImplCtx) override;
 130 };
 131
 132 class BlockObjCVariableTraverser : public ASTTraverser {
 133 public:
 134   void traverseBody(BodyContext &BodyCtx) override;
 135 };
 136
 137 class ProtectedScopeTraverser : public ASTTraverser {
 138 public:
 139   void traverseBody(BodyContext &BodyCtx) override;
 140 };
 141
 142 // GC transformations
 143
 144 class GCAttrsTraverser : public ASTTraverser {
 145 public:
 146   void traverseTU(MigrationContext &MigrateCtx) override;
 147 };
 148
 149 class GCCollectableCallsTraverser : public ASTTraverser {
 150 public:
 151   void traverseBody(BodyContext &BodyCtx) override;
 152 };
 153
 154 //===----------------------------------------------------------------------===//
 155 // Helpers.
 156 //===----------------------------------------------------------------------===//
 157
 158 /// Determine whether we can add weak to the given type.
 159 bool canApplyWeak(ASTContext &Ctx, QualType type,
 160                   bool AllowOnUnknownClass = false);
 161
 162 bool isPlusOneAssign(const BinaryOperator *E);
 163 bool isPlusOne(const Expr *E);
 164
 165 /// 'Loc' is the end of a statement range. This returns the location
 166 /// immediately after the semicolon following the statement.
 167 /// If no semicolon is found or the location is inside a macro, the returned
 168 /// source location will be invalid.
 169 SourceLocation findLocationAfterSemi(SourceLocation loc, ASTContext &Ctx,
 170                                      bool IsDecl = false);
 171
 172 /// 'Loc' is the end of a statement range. This returns the location
 173 /// of the semicolon following the statement.
 174 /// If no semicolon is found or the location is inside a macro, the returned
 175 /// source location will be invalid.
 176 SourceLocation findSemiAfterLocation(SourceLocation loc, ASTContext &Ctx,
 177                                      bool IsDecl = false);
 178
 179 bool hasSideEffects(Expr *E, ASTContext &Ctx);
 180 bool isGlobalVar(Expr *E);
 181 /// Returns "nil" or "0" if 'nil' macro is not actually defined.
 182 StringRef getNilString(MigrationPass &Pass);
 183
 184 template <typename BODY_TRANS>
 185 class BodyTransform : public RecursiveASTVisitor<BodyTransform<BODY_TRANS> > {
 186   MigrationPass &Pass;
 187   Decl *ParentD;
 188
 189   typedef RecursiveASTVisitor<BodyTransform<BODY_TRANS> > base;
 190 public:
 191   BodyTransform(MigrationPass &pass) : Pass(pass), ParentD(nullptr) { }
 192
 193   bool TraverseStmt(Stmt *rootS) {
 194     if (rootS)
 195       BODY_TRANS(Pass).transformBody(rootS, ParentD);
 196     return true;
 197   }
 198
 199   bool TraverseObjCMethodDecl(ObjCMethodDecl *D) {
 200     SaveAndRestore<Decl *> SetParent(ParentD, D);
 201     return base::TraverseObjCMethodDecl(D);
 202   }
 203 };
 204
 205 typedef llvm::DenseSet<Expr *> ExprSet;
 206
 207 void clearRefsIn(Stmt *S, ExprSet &refs);
 208 template <typename iterator>
 209 void clearRefsIn(iterator begin, iterator end, ExprSet &refs) {
 210   for (; begin != end; ++begin)
 211     clearRefsIn(*begin, refs);
 212 }
 213
 214 void collectRefs(ValueDecl *D, Stmt *S, ExprSet &refs);
 215
 216 void collectRemovables(Stmt *S, ExprSet &exprs);
 217
 218 } // end namespace trans
 219
 220 } // end namespace arcmt
 221
 222 } // end namespace clang
 223
 224 #endif