167bc6071d7abea2d4870bc4fd8f119ebd93c46f3Francois Pichet//===--- JumpDiagnostics.cpp - Protected scope jump analysis ------*- C++ -*-=// 25af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// 35af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// The LLVM Compiler Infrastructure 45af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// 55af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// This file is distributed under the University of Illinois Open Source 65af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// License. See LICENSE.TXT for details. 75af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// 85af280ce21af061f96b5b5b752746871e364ba99Chris Lattner//===----------------------------------------------------------------------===// 95af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// 105af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// This file implements the JumpScopeChecker class, which is used to diagnose 1167bc6071d7abea2d4870bc4fd8f119ebd93c46f3Francois Pichet// jumps that enter a protected scope in an invalid way. 125af280ce21af061f96b5b5b752746871e364ba99Chris Lattner// 135af280ce21af061f96b5b5b752746871e364ba99Chris Lattner//===----------------------------------------------------------------------===// 145af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 152d88708cbe4e4ec5e04e4acb6bd7f5be68557379John McCall#include "clang/Sema/SemaInternal.h" 16384aff8b94bb0d1ad6c5667b90621e5699815bb2John McCall#include "clang/AST/DeclCXX.h" 175af280ce21af061f96b5b5b752746871e364ba99Chris Lattner#include "clang/AST/Expr.h" 18e413516d0ed61ef9e2ff706bcc00480adca947c4Douglas Gregor#include "clang/AST/ExprCXX.h" 1916f0049415ec596504891259e2a83e19871c0d52Chris Lattner#include "clang/AST/StmtObjC.h" 20972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl#include "clang/AST/StmtCXX.h" 21e737f5041a36d0befb39ffeed8d50ba15916d3daDouglas Gregor#include "llvm/ADT/BitVector.h" 225af280ce21af061f96b5b5b752746871e364ba99Chris Lattnerusing namespace clang; 235af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 245af280ce21af061f96b5b5b752746871e364ba99Chris Lattnernamespace { 255af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 265af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// JumpScopeChecker - This object is used by Sema to diagnose invalid jumps 275af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// into VLA and other protected scopes. For example, this rejects: 285af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// goto L; 295af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// int a[n]; 305af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// L: 315af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// 325af280ce21af061f96b5b5b752746871e364ba99Chris Lattnerclass JumpScopeChecker { 335af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Sema &S; 341eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 355af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// GotoScope - This is a record that we use to keep track of all of the 365af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// scopes that are introduced by VLAs and other things that scope jumps like 375af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// gotos. This scope tree has nothing to do with the source scope tree, 385af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// because you can have multiple VLA scopes per compound statement, and most 395af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// compound statements don't introduce any scopes. 405af280ce21af061f96b5b5b752746871e364ba99Chris Lattner struct GotoScope { 415af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// ParentScope - The index in ScopeMap of the parent scope. This is 0 for 425af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// the parent scope is the function body. 435af280ce21af061f96b5b5b752746871e364ba99Chris Lattner unsigned ParentScope; 441eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 450e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith /// InDiag - The note to emit if there is a jump into this scope. 46ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned InDiag; 47ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 480e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith /// OutDiag - The note to emit if there is an indirect jump out 49ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall /// of this scope. Direct jumps always clean up their current scope 50ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall /// in an orderly way. 51ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned OutDiag; 521eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 535af280ce21af061f96b5b5b752746871e364ba99Chris Lattner /// Loc - Location to emit the diagnostic. 545af280ce21af061f96b5b5b752746871e364ba99Chris Lattner SourceLocation Loc; 551eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 56ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall GotoScope(unsigned parentScope, unsigned InDiag, unsigned OutDiag, 57ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall SourceLocation L) 58ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall : ParentScope(parentScope), InDiag(InDiag), OutDiag(OutDiag), Loc(L) {} 595af280ce21af061f96b5b5b752746871e364ba99Chris Lattner }; 601eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 615f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner SmallVector<GotoScope, 48> Scopes; 625af280ce21af061f96b5b5b752746871e364ba99Chris Lattner llvm::DenseMap<Stmt*, unsigned> LabelAndGotoScopes; 635f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner SmallVector<Stmt*, 16> Jumps; 64ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 655f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner SmallVector<IndirectGotoStmt*, 4> IndirectJumps; 665f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner SmallVector<LabelDecl*, 4> IndirectJumpTargets; 675af280ce21af061f96b5b5b752746871e364ba99Chris Lattnerpublic: 685af280ce21af061f96b5b5b752746871e364ba99Chris Lattner JumpScopeChecker(Stmt *Body, Sema &S); 695af280ce21af061f96b5b5b752746871e364ba99Chris Lattnerprivate: 7043dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor void BuildScopeInformation(Decl *D, unsigned &ParentScope); 714e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian void BuildScopeInformation(VarDecl *D, const BlockDecl *BDecl, 724e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned &ParentScope); 734e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian void BuildScopeInformation(Stmt *S, unsigned &origParentScope); 744e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 755af280ce21af061f96b5b5b752746871e364ba99Chris Lattner void VerifyJumps(); 76ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall void VerifyIndirectJumps(); 774fe5be028b723fedc28bb33be96cde1ab2574ee6Bill Wendling void NoteJumpIntoScopes(ArrayRef<unsigned> ToScopes); 78ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall void DiagnoseIndirectJump(IndirectGotoStmt *IG, unsigned IGScope, 79ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *Target, unsigned TargetScope); 80c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet void CheckJump(Stmt *From, Stmt *To, SourceLocation DiagLoc, 810e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith unsigned JumpDiag, unsigned JumpDiagWarning, 820e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith unsigned JumpDiagCXX98Compat); 835e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall 845e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall unsigned GetDeepestCommonScope(unsigned A, unsigned B); 855af280ce21af061f96b5b5b752746871e364ba99Chris Lattner}; 865af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} // end anonymous namespace 875af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 885af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 895af280ce21af061f96b5b5b752746871e364ba99Chris LattnerJumpScopeChecker::JumpScopeChecker(Stmt *Body, Sema &s) : S(s) { 905af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Add a scope entry for function scope. 91ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Scopes.push_back(GotoScope(~0U, ~0U, ~0U, SourceLocation())); 921eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 935af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Build information for the top level compound statement, so that we have a 945af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // defined scope record for every "goto" and label. 954e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned BodyParentScope = 0; 964e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(Body, BodyParentScope); 971eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 985af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Check that all jumps we saw are kosher. 995af280ce21af061f96b5b5b752746871e364ba99Chris Lattner VerifyJumps(); 100ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall VerifyIndirectJumps(); 1015af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 1021eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 1035e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// GetDeepestCommonScope - Finds the innermost scope enclosing the 1045e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// two scopes. 1055e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCallunsigned JumpScopeChecker::GetDeepestCommonScope(unsigned A, unsigned B) { 1065e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall while (A != B) { 1075e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Inner scopes are created after outer scopes and therefore have 1085e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // higher indices. 1095e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall if (A < B) { 1105e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall assert(Scopes[B].ParentScope < B); 1115e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall B = Scopes[B].ParentScope; 1125e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall } else { 1135e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall assert(Scopes[A].ParentScope < A); 1145e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall A = Scopes[A].ParentScope; 1155e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall } 1165e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall } 1175e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall return A; 1185e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall} 1195e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall 120f85e193739c953358c865005855253af4f68a497John McCalltypedef std::pair<unsigned,unsigned> ScopePair; 121f85e193739c953358c865005855253af4f68a497John McCall 1225af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// GetDiagForGotoScopeDecl - If this decl induces a new goto scope, return a 1235af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// diagnostic that should be emitted if control goes over it. If not, return 0. 124f85e193739c953358c865005855253af4f68a497John McCallstatic ScopePair GetDiagForGotoScopeDecl(ASTContext &Context, const Decl *D) { 1255af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 126ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned InDiag = 0, OutDiag = 0; 1275af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (VD->getType()->isVariablyModifiedType()) 128ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall InDiag = diag::note_protected_by_vla; 129ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 130f85e193739c953358c865005855253af4f68a497John McCall if (VD->hasAttr<BlocksAttr>()) 131f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(diag::note_protected_by___block, 132f85e193739c953358c865005855253af4f68a497John McCall diag::note_exits___block); 133f85e193739c953358c865005855253af4f68a497John McCall 134f85e193739c953358c865005855253af4f68a497John McCall if (VD->hasAttr<CleanupAttr>()) 135f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(diag::note_protected_by_cleanup, 136f85e193739c953358c865005855253af4f68a497John McCall diag::note_exits_cleanup); 137f85e193739c953358c865005855253af4f68a497John McCall 1384e4d08403ca5cfd4d558fa2936215d3a4e5a528dDavid Blaikie if (Context.getLangOpts().ObjCAutoRefCount && VD->hasLocalStorage()) { 139f85e193739c953358c865005855253af4f68a497John McCall switch (VD->getType().getObjCLifetime()) { 140f85e193739c953358c865005855253af4f68a497John McCall case Qualifiers::OCL_None: 141f85e193739c953358c865005855253af4f68a497John McCall case Qualifiers::OCL_ExplicitNone: 142f85e193739c953358c865005855253af4f68a497John McCall case Qualifiers::OCL_Autoreleasing: 143f85e193739c953358c865005855253af4f68a497John McCall break; 144f85e193739c953358c865005855253af4f68a497John McCall 145f85e193739c953358c865005855253af4f68a497John McCall case Qualifiers::OCL_Strong: 146f85e193739c953358c865005855253af4f68a497John McCall case Qualifiers::OCL_Weak: 147b8b0313e84700b5c6d597b3be4de41c97b7550f1Argyrios Kyrtzidis return ScopePair(diag::note_protected_by_objc_ownership, 148b8b0313e84700b5c6d597b3be4de41c97b7550f1Argyrios Kyrtzidis diag::note_exits_objc_ownership); 149f85e193739c953358c865005855253af4f68a497John McCall } 150f85e193739c953358c865005855253af4f68a497John McCall } 151f85e193739c953358c865005855253af4f68a497John McCall 1524e4d08403ca5cfd4d558fa2936215d3a4e5a528dDavid Blaikie if (Context.getLangOpts().CPlusPlus && VD->hasLocalStorage()) { 1530e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith // C++11 [stmt.dcl]p3: 154f85e193739c953358c865005855253af4f68a497John McCall // A program that jumps from a point where a variable with automatic 155f85e193739c953358c865005855253af4f68a497John McCall // storage duration is not in scope to a point where it is in scope 156f85e193739c953358c865005855253af4f68a497John McCall // is ill-formed unless the variable has scalar type, class type with 157f85e193739c953358c865005855253af4f68a497John McCall // a trivial default constructor and a trivial destructor, a 158f85e193739c953358c865005855253af4f68a497John McCall // cv-qualified version of one of these types, or an array of one of 159f85e193739c953358c865005855253af4f68a497John McCall // the preceding types and is declared without an initializer. 160f85e193739c953358c865005855253af4f68a497John McCall 161f85e193739c953358c865005855253af4f68a497John McCall // C++03 [stmt.dcl.p3: 162f85e193739c953358c865005855253af4f68a497John McCall // A program that jumps from a point where a local variable 163f85e193739c953358c865005855253af4f68a497John McCall // with automatic storage duration is not in scope to a point 164f85e193739c953358c865005855253af4f68a497John McCall // where it is in scope is ill-formed unless the variable has 165f85e193739c953358c865005855253af4f68a497John McCall // POD type and is declared without an initializer. 166f85e193739c953358c865005855253af4f68a497John McCall 167f85e193739c953358c865005855253af4f68a497John McCall if (const Expr *init = VD->getInit()) { 168f85e193739c953358c865005855253af4f68a497John McCall // We actually give variables of record type (or array thereof) 169f85e193739c953358c865005855253af4f68a497John McCall // an initializer even if that initializer only calls a trivial 170f85e193739c953358c865005855253af4f68a497John McCall // ctor. Detect that case. 171f85e193739c953358c865005855253af4f68a497John McCall // FIXME: With generalized initializer lists, this may 172f85e193739c953358c865005855253af4f68a497John McCall // classify "X x{};" as having no initializer. 173f85e193739c953358c865005855253af4f68a497John McCall unsigned inDiagToUse = diag::note_protected_by_variable_init; 174f85e193739c953358c865005855253af4f68a497John McCall 175f85e193739c953358c865005855253af4f68a497John McCall const CXXRecordDecl *record = 0; 176f85e193739c953358c865005855253af4f68a497John McCall 177f85e193739c953358c865005855253af4f68a497John McCall if (const CXXConstructExpr *cce = dyn_cast<CXXConstructExpr>(init)) { 178f85e193739c953358c865005855253af4f68a497John McCall const CXXConstructorDecl *ctor = cce->getConstructor(); 179f85e193739c953358c865005855253af4f68a497John McCall record = ctor->getParent(); 180f85e193739c953358c865005855253af4f68a497John McCall 181f85e193739c953358c865005855253af4f68a497John McCall if (ctor->isTrivial() && ctor->isDefaultConstructor()) { 1820e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (!record->hasTrivialDestructor()) 1830e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith inDiagToUse = diag::note_protected_by_variable_nontriv_destructor; 1840e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith else if (!record->isPOD()) 1850e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith inDiagToUse = diag::note_protected_by_variable_non_pod; 1860e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith else 1870e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith inDiagToUse = 0; 188e413516d0ed61ef9e2ff706bcc00480adca947c4Douglas Gregor } 189f85e193739c953358c865005855253af4f68a497John McCall } else if (VD->getType()->isArrayType()) { 190f85e193739c953358c865005855253af4f68a497John McCall record = VD->getType()->getBaseElementTypeUnsafe() 191f85e193739c953358c865005855253af4f68a497John McCall ->getAsCXXRecordDecl(); 192e413516d0ed61ef9e2ff706bcc00480adca947c4Douglas Gregor } 193f85e193739c953358c865005855253af4f68a497John McCall 194f85e193739c953358c865005855253af4f68a497John McCall if (inDiagToUse) 195f85e193739c953358c865005855253af4f68a497John McCall InDiag = inDiagToUse; 196f85e193739c953358c865005855253af4f68a497John McCall 197f85e193739c953358c865005855253af4f68a497John McCall // Also object to indirect jumps which leave scopes with dtors. 198f85e193739c953358c865005855253af4f68a497John McCall if (record && !record->hasTrivialDestructor()) 199f61103ef335fb273a98c1389e6fddaf796feb4b3Douglas Gregor OutDiag = diag::note_exits_dtor; 200025291b591a528d8a3f303991f65e19fa1e90a9dDouglas Gregor } 201ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 2026d97e5e4b7abdae710c2548b51f4ed0298e86d80Chris Lattner 203f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(InDiag, OutDiag); 204ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 205ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 206ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (const TypedefDecl *TD = dyn_cast<TypedefDecl>(D)) { 2075af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (TD->getUnderlyingType()->isVariablyModifiedType()) 208f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(diag::note_protected_by_vla_typedef, 0); 2095af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 2101eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 211162e1c1b487352434552147967c3dd296ebee2f7Richard Smith if (const TypeAliasDecl *TD = dyn_cast<TypeAliasDecl>(D)) { 212162e1c1b487352434552147967c3dd296ebee2f7Richard Smith if (TD->getUnderlyingType()->isVariablyModifiedType()) 213f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(diag::note_protected_by_vla_type_alias, 0); 214162e1c1b487352434552147967c3dd296ebee2f7Richard Smith } 215162e1c1b487352434552147967c3dd296ebee2f7Richard Smith 216f85e193739c953358c865005855253af4f68a497John McCall return ScopePair(0U, 0U); 2175af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 2185af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 21943dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor/// \brief Build scope information for a declaration that is part of a DeclStmt. 22043dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregorvoid JumpScopeChecker::BuildScopeInformation(Decl *D, unsigned &ParentScope) { 22143dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // If this decl causes a new scope, push and switch to it. 222f85e193739c953358c865005855253af4f68a497John McCall std::pair<unsigned,unsigned> Diags = GetDiagForGotoScopeDecl(S.Context, D); 22343dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor if (Diags.first || Diags.second) { 22443dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor Scopes.push_back(GotoScope(ParentScope, Diags.first, Diags.second, 22543dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor D->getLocation())); 22643dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor ParentScope = Scopes.size()-1; 22743dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor } 22843dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor 22943dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // If the decl has an initializer, walk it with the potentially new 23043dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // scope we just installed. 23143dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor if (VarDecl *VD = dyn_cast<VarDecl>(D)) 23243dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor if (Expr *Init = VD->getInit()) 23343dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor BuildScopeInformation(Init, ParentScope); 23443dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor} 2355af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 2364e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian/// \brief Build scope information for a captured block literal variables. 2374e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanianvoid JumpScopeChecker::BuildScopeInformation(VarDecl *D, 2384e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian const BlockDecl *BDecl, 2394e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned &ParentScope) { 2404e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian // exclude captured __block variables; there's no destructor 2414e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian // associated with the block literal for them. 2424e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian if (D->hasAttr<BlocksAttr>()) 2434e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian return; 2444e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian QualType T = D->getType(); 2454e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian QualType::DestructionKind destructKind = T.isDestructedType(); 2464e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian if (destructKind != QualType::DK_none) { 2474e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian std::pair<unsigned,unsigned> Diags; 2484e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian switch (destructKind) { 2494e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian case QualType::DK_cxx_destructor: 2504e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Diags = ScopePair(diag::note_enters_block_captures_cxx_obj, 2514e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian diag::note_exits_block_captures_cxx_obj); 2524e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian break; 2534e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian case QualType::DK_objc_strong_lifetime: 2544e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Diags = ScopePair(diag::note_enters_block_captures_strong, 2554e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian diag::note_exits_block_captures_strong); 2564e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian break; 2574e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian case QualType::DK_objc_weak_lifetime: 2584e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Diags = ScopePair(diag::note_enters_block_captures_weak, 2594e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian diag::note_exits_block_captures_weak); 2604e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian break; 2614e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian case QualType::DK_none: 2620e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith llvm_unreachable("non-lifetime captured variable"); 2634e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian } 2644e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian SourceLocation Loc = D->getLocation(); 2654e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian if (Loc.isInvalid()) 2664e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Loc = BDecl->getLocation(); 2674e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Scopes.push_back(GotoScope(ParentScope, 2684e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian Diags.first, Diags.second, Loc)); 2694e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian ParentScope = Scopes.size()-1; 2704e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian } 2714e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian} 2724e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 2735af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// BuildScopeInformation - The statements from CI to CE are known to form a 2745af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// coherent VLA scope with a specified parent node. Walk through the 2755af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// statements, adding any labels or gotos to LabelAndGotoScopes and recursively 2765af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// walking the AST as needed. 2774e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanianvoid JumpScopeChecker::BuildScopeInformation(Stmt *S, unsigned &origParentScope) { 2784e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian // If this is a statement, rather than an expression, scopes within it don't 2794e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian // propagate out into the enclosing scope. Otherwise we have to worry 2804e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian // about block literals, which have the lifetime of their enclosing statement. 2814e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned independentParentScope = origParentScope; 2824e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned &ParentScope = ((isa<Expr>(S) && !isa<StmtExpr>(S)) 2834e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian ? origParentScope : independentParentScope); 2844e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 28543dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor bool SkipFirstSubStmt = false; 28643dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor 2875af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // If we found a label, remember that it is in ParentScope scope. 288ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall switch (S->getStmtClass()) { 289ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall case Stmt::AddrLabelExprClass: 290ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall IndirectJumpTargets.push_back(cast<AddrLabelExpr>(S)->getLabel()); 291ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall break; 292ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 293ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall case Stmt::IndirectGotoStmtClass: 29495c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // "goto *&&lbl;" is a special case which we treat as equivalent 29595c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // to a normal goto. In addition, we don't calculate scope in the 29695c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // operand (to avoid recording the address-of-label use), which 29795c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // works only because of the restricted set of expressions which 29895c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // we detect as constant targets. 29995c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall if (cast<IndirectGotoStmt>(S)->getConstantTarget()) { 30095c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall LabelAndGotoScopes[S] = ParentScope; 30195c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall Jumps.push_back(S); 30295c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall return; 30395c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall } 30495c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall 3055af280ce21af061f96b5b5b752746871e364ba99Chris Lattner LabelAndGotoScopes[S] = ParentScope; 306ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall IndirectJumps.push_back(cast<IndirectGotoStmt>(S)); 307ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall break; 308ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 309ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall case Stmt::SwitchStmtClass: 31043dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // Evaluate the condition variable before entering the scope of the switch 31143dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // statement. 31243dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor if (VarDecl *Var = cast<SwitchStmt>(S)->getConditionVariable()) { 31343dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor BuildScopeInformation(Var, ParentScope); 31443dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor SkipFirstSubStmt = true; 31543dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor } 31643dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor // Fall through 31743dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor 31843dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor case Stmt::GotoStmtClass: 3195af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Remember both what scope a goto is in as well as the fact that we have 3205af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // it. This makes the second scan not have to walk the AST again. 3215af280ce21af061f96b5b5b752746871e364ba99Chris Lattner LabelAndGotoScopes[S] = ParentScope; 3225af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Jumps.push_back(S); 323ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall break; 324ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 325ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall default: 326ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall break; 3275af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 3281eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 3297502c1d3ce8bb97bcc4f7bebef507040bd93b26fJohn McCall for (Stmt::child_range CI = S->children(); CI; ++CI) { 33043dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor if (SkipFirstSubStmt) { 33143dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor SkipFirstSubStmt = false; 33243dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor continue; 33343dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor } 33443dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor 3355af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Stmt *SubStmt = *CI; 3365af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (SubStmt == 0) continue; 3371eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 33897ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall // Cases, labels, and defaults aren't "scope parents". It's also 33997ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall // important to handle these iteratively instead of recursively in 34097ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall // order to avoid blowing out the stack. 34197ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall while (true) { 34297ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall Stmt *Next; 343ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner if (CaseStmt *CS = dyn_cast<CaseStmt>(SubStmt)) 344ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner Next = CS->getSubStmt(); 345ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner else if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SubStmt)) 346ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner Next = DS->getSubStmt(); 347ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner else if (LabelStmt *LS = dyn_cast<LabelStmt>(SubStmt)) 348ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner Next = LS->getSubStmt(); 34997ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall else 35097ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall break; 35197ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall 35297ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall LabelAndGotoScopes[SubStmt] = ParentScope; 35397ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall SubStmt = Next; 35497ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall } 35597ba481f3f45e5b63b4a354bfb471ce146b7de57John McCall 3565af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // If this is a declstmt with a VLA definition, it defines a scope from here 3575af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // to the end of the containing context. 3585af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (DeclStmt *DS = dyn_cast<DeclStmt>(SubStmt)) { 3596d97e5e4b7abdae710c2548b51f4ed0298e86d80Chris Lattner // The decl statement creates a scope if any of the decls in it are VLAs 3606d97e5e4b7abdae710c2548b51f4ed0298e86d80Chris Lattner // or have the cleanup attribute. 3615af280ce21af061f96b5b5b752746871e364ba99Chris Lattner for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end(); 36243dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor I != E; ++I) 36343dec6bbde2d0a16c35978983761c8b7030c8e18Douglas Gregor BuildScopeInformation(*I, ParentScope); 3645af280ce21af061f96b5b5b752746871e364ba99Chris Lattner continue; 3655af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 3665af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Disallow jumps into any part of an @try statement by pushing a scope and 3675af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // walking all sub-stmts in that scope. 3685af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (ObjCAtTryStmt *AT = dyn_cast<ObjCAtTryStmt>(SubStmt)) { 3694e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned newParentScope; 3705af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Recursively walk the AST for the @try part. 371ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Scopes.push_back(GotoScope(ParentScope, 372ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_protected_by_objc_try, 373ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_objc_try, 3745af280ce21af061f96b5b5b752746871e364ba99Chris Lattner AT->getAtTryLoc())); 3755af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (Stmt *TryPart = AT->getTryBody()) 3764e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(TryPart, (newParentScope = Scopes.size()-1)); 3775af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 3785af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Jump from the catch to the finally or try is not valid. 3798f5e3dd32e443768d9dbbad7191e123e6733750cDouglas Gregor for (unsigned I = 0, N = AT->getNumCatchStmts(); I != N; ++I) { 3808f5e3dd32e443768d9dbbad7191e123e6733750cDouglas Gregor ObjCAtCatchStmt *AC = AT->getCatchStmt(I); 3815af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Scopes.push_back(GotoScope(ParentScope, 3825af280ce21af061f96b5b5b752746871e364ba99Chris Lattner diag::note_protected_by_objc_catch, 383ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_objc_catch, 3845af280ce21af061f96b5b5b752746871e364ba99Chris Lattner AC->getAtCatchLoc())); 3851eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump // @catches are nested and it isn't 3864e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(AC->getCatchBody(), 3874e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian (newParentScope = Scopes.size()-1)); 3885af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 3891eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 3905af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Jump from the finally to the try or catch is not valid. 3915af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (ObjCAtFinallyStmt *AF = AT->getFinallyStmt()) { 3925af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Scopes.push_back(GotoScope(ParentScope, 3935af280ce21af061f96b5b5b752746871e364ba99Chris Lattner diag::note_protected_by_objc_finally, 394ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_objc_finally, 3955af280ce21af061f96b5b5b752746871e364ba99Chris Lattner AF->getAtFinallyLoc())); 3964e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(AF, (newParentScope = Scopes.size()-1)); 3975af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 3981eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 3995af280ce21af061f96b5b5b752746871e364ba99Chris Lattner continue; 4005af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 4014e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 4024e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian unsigned newParentScope; 40346c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // Disallow jumps into the protected statement of an @synchronized, but 40446c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // allow jumps into the object expression it protects. 40546c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner if (ObjCAtSynchronizedStmt *AS = dyn_cast<ObjCAtSynchronizedStmt>(SubStmt)){ 40646c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // Recursively walk the AST for the @synchronized object expr, it is 40746c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // evaluated in the normal scope. 40846c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner BuildScopeInformation(AS->getSynchExpr(), ParentScope); 4091eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 41046c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // Recursively walk the AST for the @synchronized part, protected by a new 41146c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner // scope. 41246c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner Scopes.push_back(GotoScope(ParentScope, 41346c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner diag::note_protected_by_objc_synchronized, 414ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_objc_synchronized, 41546c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner AS->getAtSynchronizedLoc())); 4164e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(AS->getSynchBody(), 4174e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian (newParentScope = Scopes.size()-1)); 41846c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner continue; 41946c3c4ba78766ac0f1c5ec631b424773e21f5271Chris Lattner } 420972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl 421972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl // Disallow jumps into any part of a C++ try statement. This is pretty 422972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl // much the same as for Obj-C. 423972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl if (CXXTryStmt *TS = dyn_cast<CXXTryStmt>(SubStmt)) { 424ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Scopes.push_back(GotoScope(ParentScope, 425ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_protected_by_cxx_try, 426ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_cxx_try, 427972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl TS->getSourceRange().getBegin())); 428972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl if (Stmt *TryBlock = TS->getTryBlock()) 4294e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(TryBlock, (newParentScope = Scopes.size()-1)); 430972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl 431972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl // Jump from the catch into the try is not allowed either. 4321eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump for (unsigned I = 0, E = TS->getNumHandlers(); I != E; ++I) { 433972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl CXXCatchStmt *CS = TS->getHandler(I); 434972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl Scopes.push_back(GotoScope(ParentScope, 435972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl diag::note_protected_by_cxx_catch, 436ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::note_exits_cxx_catch, 437972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl CS->getSourceRange().getBegin())); 4384e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(CS->getHandlerBlock(), 4394e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian (newParentScope = Scopes.size()-1)); 440972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl } 441972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl 442972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl continue; 443972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl } 444972041f45bdf8df7ea447221292d7827466ba94bSebastian Redl 445f85e193739c953358c865005855253af4f68a497John McCall // Disallow jumps into the protected statement of an @autoreleasepool. 446f85e193739c953358c865005855253af4f68a497John McCall if (ObjCAutoreleasePoolStmt *AS = dyn_cast<ObjCAutoreleasePoolStmt>(SubStmt)){ 447f85e193739c953358c865005855253af4f68a497John McCall // Recursively walk the AST for the @autoreleasepool part, protected by a new 448f85e193739c953358c865005855253af4f68a497John McCall // scope. 449f85e193739c953358c865005855253af4f68a497John McCall Scopes.push_back(GotoScope(ParentScope, 450f85e193739c953358c865005855253af4f68a497John McCall diag::note_protected_by_objc_autoreleasepool, 451f85e193739c953358c865005855253af4f68a497John McCall diag::note_exits_objc_autoreleasepool, 452f85e193739c953358c865005855253af4f68a497John McCall AS->getAtLoc())); 4534e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(AS->getSubStmt(), (newParentScope = Scopes.size()-1)); 454f85e193739c953358c865005855253af4f68a497John McCall continue; 455f85e193739c953358c865005855253af4f68a497John McCall } 4564e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 4574e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian if (const BlockExpr *BE = dyn_cast<BlockExpr>(SubStmt)) { 4584e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian const BlockDecl *BDecl = BE->getBlockDecl(); 4594e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian for (BlockDecl::capture_const_iterator ci = BDecl->capture_begin(), 4604e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian ce = BDecl->capture_end(); ci != ce; ++ci) { 4614e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian VarDecl *variable = ci->getVariable(); 4624e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian BuildScopeInformation(variable, BDecl, ParentScope); 4634e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian } 4644e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian } 4654e7c7f2b78ac3930e45f00626ef6acf08b3f80caFariborz Jahanian 4665af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Recursively walk the AST. 4675af280ce21af061f96b5b5b752746871e364ba99Chris Lattner BuildScopeInformation(SubStmt, ParentScope); 4685af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 4695af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 4705af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 4715af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// VerifyJumps - Verify each element of the Jumps array to see if they are 4725af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// valid, emitting diagnostics if not. 4735af280ce21af061f96b5b5b752746871e364ba99Chris Lattnervoid JumpScopeChecker::VerifyJumps() { 4745af280ce21af061f96b5b5b752746871e364ba99Chris Lattner while (!Jumps.empty()) { 4755af280ce21af061f96b5b5b752746871e364ba99Chris Lattner Stmt *Jump = Jumps.pop_back_val(); 4761eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 4771eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump // With a goto, 4785af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (GotoStmt *GS = dyn_cast<GotoStmt>(Jump)) { 479ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner CheckJump(GS, GS->getLabel()->getStmt(), GS->getGotoLoc(), 480c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet diag::err_goto_into_protected_scope, 4810e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_goto_into_protected_scope, 4820e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_cxx98_compat_goto_into_protected_scope); 4835af280ce21af061f96b5b5b752746871e364ba99Chris Lattner continue; 4845af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 4851eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 48695c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall // We only get indirect gotos here when they have a constant target. 48795c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall if (IndirectGotoStmt *IGS = dyn_cast<IndirectGotoStmt>(Jump)) { 488ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *Target = IGS->getConstantTarget(); 489ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner CheckJump(IGS, Target->getStmt(), IGS->getGotoLoc(), 4902e96511773c6a21291dfa5218eb8ba79f04b5318Francois Pichet diag::err_goto_into_protected_scope, 4910e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_goto_into_protected_scope, 4920e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_cxx98_compat_goto_into_protected_scope); 49395c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall continue; 49495c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall } 49595c225de9fa3d79f70ef5008c0279580a7d9dcadJohn McCall 496ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall SwitchStmt *SS = cast<SwitchStmt>(Jump); 497ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall for (SwitchCase *SC = SS->getSwitchCaseList(); SC; 498ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall SC = SC->getNextSwitchCase()) { 499ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall assert(LabelAndGotoScopes.count(SC) && "Case not visited?"); 500ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall CheckJump(SS, SC, SC->getLocStart(), 5010e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::err_switch_into_protected_scope, 0, 5020e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_cxx98_compat_switch_into_protected_scope); 5035af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 504ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 505ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall} 506ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 5075e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// VerifyIndirectJumps - Verify whether any possible indirect jump 5085e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// might cross a protection boundary. Unlike direct jumps, indirect 5095e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// jumps count cleanups as protection boundaries: since there's no 5105e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// way to know where the jump is going, we can't implicitly run the 5115e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// right cleanups the way we can with direct jumps. 5125e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// 5135e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// Thus, an indirect jump is "trivial" if it bypasses no 5145e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// initializations and no teardowns. More formally, an indirect jump 5155e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// from A to B is trivial if the path out from A to DCA(A,B) is 5165e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// trivial and the path in from DCA(A,B) to B is trivial, where 5175e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// DCA(A,B) is the deepest common ancestor of A and B. 5185e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// Jump-triviality is transitive but asymmetric. 519ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall/// 520ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall/// A path in is trivial if none of the entered scopes have an InDiag. 521ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall/// A path out is trivial is none of the exited scopes have an OutDiag. 5225e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// 5235e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// Under these definitions, this function checks that the indirect 5245e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// jump between A and B is trivial for every indirect goto statement A 5255e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// and every label B whose address was taken in the function. 526ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCallvoid JumpScopeChecker::VerifyIndirectJumps() { 527ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (IndirectJumps.empty()) return; 528ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 529ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // If there aren't any address-of-label expressions in this function, 530ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // complain about the first indirect goto. 531ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (IndirectJumpTargets.empty()) { 532ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall S.Diag(IndirectJumps[0]->getGotoLoc(), 533ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall diag::err_indirect_goto_without_addrlabel); 534ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall return; 535ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 536ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 5375e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Collect a single representative of every scope containing an 5385e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // indirect goto. For most code bases, this substantially cuts 5395e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // down on the number of jump sites we'll have to consider later. 540ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall typedef std::pair<unsigned, IndirectGotoStmt*> JumpScope; 5415f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner SmallVector<JumpScope, 32> JumpScopes; 542ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall { 543ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall llvm::DenseMap<unsigned, IndirectGotoStmt*> JumpScopesMap; 5445f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner for (SmallVectorImpl<IndirectGotoStmt*>::iterator 545ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall I = IndirectJumps.begin(), E = IndirectJumps.end(); I != E; ++I) { 546ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall IndirectGotoStmt *IG = *I; 547ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall assert(LabelAndGotoScopes.count(IG) && 548ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall "indirect jump didn't get added to scopes?"); 549ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned IGScope = LabelAndGotoScopes[IG]; 550ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall IndirectGotoStmt *&Entry = JumpScopesMap[IGScope]; 551ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (!Entry) Entry = IG; 552ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 553ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall JumpScopes.reserve(JumpScopesMap.size()); 554ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall for (llvm::DenseMap<unsigned, IndirectGotoStmt*>::iterator 555ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall I = JumpScopesMap.begin(), E = JumpScopesMap.end(); I != E; ++I) 556ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall JumpScopes.push_back(*I); 557ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 558ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 5595e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Collect a single representative of every scope containing a 5605e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // label whose address was taken somewhere in the function. 5615e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // For most code bases, there will be only one such scope. 562ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner llvm::DenseMap<unsigned, LabelDecl*> TargetScopes; 5635f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner for (SmallVectorImpl<LabelDecl*>::iterator 564ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall I = IndirectJumpTargets.begin(), E = IndirectJumpTargets.end(); 565ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall I != E; ++I) { 566ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *TheLabel = *I; 567ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner assert(LabelAndGotoScopes.count(TheLabel->getStmt()) && 568ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall "Referenced label didn't get added to scopes?"); 569ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner unsigned LabelScope = LabelAndGotoScopes[TheLabel->getStmt()]; 570ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *&Target = TargetScopes[LabelScope]; 571ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (!Target) Target = TheLabel; 572ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 573ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 5745e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // For each target scope, make sure it's trivially reachable from 5755e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // every scope containing a jump site. 5765e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // 5775e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // A path between scopes always consists of exitting zero or more 5785e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // scopes, then entering zero or more scopes. We build a set of 5795e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // of scopes S from which the target scope can be trivially 5805e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // entered, then verify that every jump scope can be trivially 5815e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // exitted to reach a scope in S. 582ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall llvm::BitVector Reachable(Scopes.size(), false); 583ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner for (llvm::DenseMap<unsigned,LabelDecl*>::iterator 584ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall TI = TargetScopes.begin(), TE = TargetScopes.end(); TI != TE; ++TI) { 585ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned TargetScope = TI->first; 586ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *TargetLabel = TI->second; 587ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 588ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Reachable.reset(); 589ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 590ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Mark all the enclosing scopes from which you can safely jump 5915e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // into the target scope. 'Min' will end up being the index of 5925e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // the shallowest such scope. 593ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned Min = TargetScope; 594ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall while (true) { 595ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Reachable.set(Min); 596ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 597ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Don't go beyond the outermost scope. 598ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (Min == 0) break; 599ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 6005e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Stop if we can't trivially enter the current scope. 601ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (Scopes[Min].InDiag) break; 6025af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 603ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Min = Scopes[Min].ParentScope; 6045af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 6055af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 606ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Walk through all the jump sites, checking that they can trivially 607ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // reach this label scope. 6085f9e272e632e951b1efe824cd16acb4d96077930Chris Lattner for (SmallVectorImpl<JumpScope>::iterator 609ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall I = JumpScopes.begin(), E = JumpScopes.end(); I != E; ++I) { 610ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned Scope = I->first; 611ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 612ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Walk out the "scope chain" for this scope, looking for a scope 6135e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // we've marked reachable. For well-formed code this amortizes 6145e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // to O(JumpScopes.size() / Scopes.size()): we only iterate 6155e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // when we see something unmarked, and in well-formed code we 6165e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // mark everything we iterate past. 617ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall bool IsReachable = false; 618ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall while (true) { 619ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (Reachable.test(Scope)) { 620ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // If we find something reachable, mark all the scopes we just 621ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // walked through as reachable. 622ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall for (unsigned S = I->first; S != Scope; S = Scopes[S].ParentScope) 623ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Reachable.set(S); 624ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall IsReachable = true; 625ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall break; 626ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 627ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 628ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Don't walk out if we've reached the top-level scope or we've 629ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // gotten shallower than the shallowest reachable scope. 630ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (Scope == 0 || Scope < Min) break; 631ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 632ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Don't walk out through an out-diagnostic. 633ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (Scopes[Scope].OutDiag) break; 634ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 635ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall Scope = Scopes[Scope].ParentScope; 636ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall } 637ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 638ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Only diagnose if we didn't find something. 639ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall if (IsReachable) continue; 640ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 641ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall DiagnoseIndirectJump(I->second, I->first, TargetLabel, TargetScope); 6425af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 6435af280ce21af061f96b5b5b752746871e364ba99Chris Lattner } 6445af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 6455af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 6460e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// Return true if a particular error+note combination must be downgraded to a 6470e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// warning in Microsoft mode. 6480e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smithstatic bool IsMicrosoftJumpWarning(unsigned JumpDiag, unsigned InDiagNote) { 6490e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith return (JumpDiag == diag::err_goto_into_protected_scope && 6500e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith (InDiagNote == diag::note_protected_by_variable_init || 6510e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith InDiagNote == diag::note_protected_by_variable_nontriv_destructor)); 6520e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith} 6530e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 6540e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// Return true if a particular note should be downgraded to a compatibility 6550e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// warning in C++11 mode. 6560e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smithstatic bool IsCXX98CompatWarning(Sema &S, unsigned InDiagNote) { 6574e4d08403ca5cfd4d558fa2936215d3a4e5a528dDavid Blaikie return S.getLangOpts().CPlusPlus0x && 6580e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith InDiagNote == diag::note_protected_by_variable_non_pod; 6590e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith} 6600e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 6610e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// Produce primary diagnostic for an indirect jump statement. 6620e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smithstatic void DiagnoseIndirectJumpStmt(Sema &S, IndirectGotoStmt *Jump, 6630e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith LabelDecl *Target, bool &Diagnosed) { 6640e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (Diagnosed) 6650e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith return; 6660e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(Jump->getGotoLoc(), diag::err_indirect_goto_in_protected_scope); 6670e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(Target->getStmt()->getIdentLoc(), diag::note_indirect_goto_target); 6680e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith Diagnosed = true; 6690e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith} 6700e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 6710e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith/// Produce note diagnostics for a jump into a protected scope. 6724fe5be028b723fedc28bb33be96cde1ab2574ee6Bill Wendlingvoid JumpScopeChecker::NoteJumpIntoScopes(ArrayRef<unsigned> ToScopes) { 6730e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith assert(!ToScopes.empty()); 6740e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith for (unsigned I = 0, E = ToScopes.size(); I != E; ++I) 6750e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (Scopes[ToScopes[I]].InDiag) 6760e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(Scopes[ToScopes[I]].Loc, Scopes[ToScopes[I]].InDiag); 6770e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith} 6780e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 6795e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall/// Diagnose an indirect jump which is known to cross scopes. 680ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCallvoid JumpScopeChecker::DiagnoseIndirectJump(IndirectGotoStmt *Jump, 681ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned JumpScope, 682ad8dcf4a9df0e24051dc31bf9e6f3cd138a34298Chris Lattner LabelDecl *Target, 683ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall unsigned TargetScope) { 684ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall assert(JumpScope != TargetScope); 685ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 6865e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall unsigned Common = GetDeepestCommonScope(JumpScope, TargetScope); 6870e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith bool Diagnosed = false; 6885e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall 6895e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Walk out the scope chain until we reach the common ancestor. 6905e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall for (unsigned I = JumpScope; I != Common; I = Scopes[I].ParentScope) 6910e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (Scopes[I].OutDiag) { 6920e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith DiagnoseIndirectJumpStmt(S, Jump, Target, Diagnosed); 6935e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall S.Diag(Scopes[I].Loc, Scopes[I].OutDiag); 6940e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith } 6950e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 6960e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith SmallVector<unsigned, 10> ToScopesCXX98Compat; 697ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 698ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall // Now walk into the scopes containing the label whose address was taken. 6995e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall for (unsigned I = TargetScope; I != Common; I = Scopes[I].ParentScope) 7000e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (IsCXX98CompatWarning(S, Scopes[I].InDiag)) 7010e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith ToScopesCXX98Compat.push_back(I); 7020e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith else if (Scopes[I].InDiag) { 7030e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith DiagnoseIndirectJumpStmt(S, Jump, Target, Diagnosed); 7045e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall S.Diag(Scopes[I].Loc, Scopes[I].InDiag); 7050e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith } 706ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 7070e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith // Diagnose this jump if it would be ill-formed in C++98. 7080e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (!Diagnosed && !ToScopesCXX98Compat.empty()) { 7090e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(Jump->getGotoLoc(), 7100e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith diag::warn_cxx98_compat_indirect_goto_in_protected_scope); 7110e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(Target->getStmt()->getIdentLoc(), diag::note_indirect_goto_target); 7120e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith NoteJumpIntoScopes(ToScopesCXX98Compat); 7130e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith } 714c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet} 715c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet 7165af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// CheckJump - Validate that the specified jump statement is valid: that it is 7175af280ce21af061f96b5b5b752746871e364ba99Chris Lattner/// jumping within or out of its current scope, not into a deeper one. 718c985b88efc9188845952ab524fe6d4717705257bFrancois Pichetvoid JumpScopeChecker::CheckJump(Stmt *From, Stmt *To, SourceLocation DiagLoc, 7190e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith unsigned JumpDiagError, unsigned JumpDiagWarning, 7200e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith unsigned JumpDiagCXX98Compat) { 7215af280ce21af061f96b5b5b752746871e364ba99Chris Lattner assert(LabelAndGotoScopes.count(From) && "Jump didn't get added to scopes?"); 7225af280ce21af061f96b5b5b752746871e364ba99Chris Lattner unsigned FromScope = LabelAndGotoScopes[From]; 7235af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 7245af280ce21af061f96b5b5b752746871e364ba99Chris Lattner assert(LabelAndGotoScopes.count(To) && "Jump didn't get added to scopes?"); 7255af280ce21af061f96b5b5b752746871e364ba99Chris Lattner unsigned ToScope = LabelAndGotoScopes[To]; 7261eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 7275af280ce21af061f96b5b5b752746871e364ba99Chris Lattner // Common case: exactly the same scope, which is fine. 7285af280ce21af061f96b5b5b752746871e364ba99Chris Lattner if (FromScope == ToScope) return; 7291eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 7305e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall unsigned CommonScope = GetDeepestCommonScope(FromScope, ToScope); 7311eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 7325e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // It's okay to jump out from a nested scope. 7335e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall if (CommonScope == ToScope) return; 7341eb4433ac451dc16f4133a88af2d002ac26c58efMike Stump 7355e2a7acbdc9e4aee4da54e1e2f560a78bf6fb3c1John McCall // Pull out (and reverse) any scopes we might need to diagnose skipping. 7360e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith SmallVector<unsigned, 10> ToScopesCXX98Compat; 737c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet SmallVector<unsigned, 10> ToScopesError; 738c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet SmallVector<unsigned, 10> ToScopesWarning; 739c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet for (unsigned I = ToScope; I != CommonScope; I = Scopes[I].ParentScope) { 7404e4d08403ca5cfd4d558fa2936215d3a4e5a528dDavid Blaikie if (S.getLangOpts().MicrosoftMode && JumpDiagWarning != 0 && 741c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet IsMicrosoftJumpWarning(JumpDiagError, Scopes[I].InDiag)) 742c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet ToScopesWarning.push_back(I); 7430e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith else if (IsCXX98CompatWarning(S, Scopes[I].InDiag)) 7440e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith ToScopesCXX98Compat.push_back(I); 745c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet else if (Scopes[I].InDiag) 746c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet ToScopesError.push_back(I); 747c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet } 748ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 749c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet // Handle warnings. 750c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet if (!ToScopesWarning.empty()) { 751c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet S.Diag(DiagLoc, JumpDiagWarning); 7520e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith NoteJumpIntoScopes(ToScopesWarning); 753c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet } 754ddb0b4d5391d3e6bc9dcf93dc42310b20c96b6fcJohn McCall 755c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet // Handle errors. 756c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet if (!ToScopesError.empty()) { 757c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet S.Diag(DiagLoc, JumpDiagError); 7580e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith NoteJumpIntoScopes(ToScopesError); 7590e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith } 7600e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith 7610e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith // Handle -Wc++98-compat warnings if the jump is well-formed. 7620e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith if (ToScopesError.empty() && !ToScopesCXX98Compat.empty()) { 7630e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith S.Diag(DiagLoc, JumpDiagCXX98Compat); 7640e9e9814a7f8313c0c02b6afea71f0e4c411873eRichard Smith NoteJumpIntoScopes(ToScopesCXX98Compat); 765c985b88efc9188845952ab524fe6d4717705257bFrancois Pichet } 7665af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 7675af280ce21af061f96b5b5b752746871e364ba99Chris Lattner 7685af280ce21af061f96b5b5b752746871e364ba99Chris Lattnervoid Sema::DiagnoseInvalidJumps(Stmt *Body) { 7696490ae5003226cae28f980648948bea8b21a8638Douglas Gregor (void)JumpScopeChecker(Body, *this); 7705af280ce21af061f96b5b5b752746871e364ba99Chris Lattner} 771