diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index 42b88f12ad14a..8ca18e2fac10c 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -208,19 +208,6 @@ template class LocOverrideScope final { } // namespace interp } // namespace clang -template -bool Compiler::isValidBitCast(const CastExpr *E) { - QualType FromTy = E->getSubExpr()->getType()->getPointeeType(); - QualType ToTy = E->getType()->getPointeeType(); - - if (classify(FromTy) == classify(ToTy)) - return true; - - if (FromTy->isVoidType() || ToTy->isVoidType()) - return true; - return false; -} - template bool Compiler::VisitCastExpr(const CastExpr *CE) { const Expr *SubExpr = CE->getSubExpr(); @@ -506,12 +493,9 @@ bool Compiler::VisitCastExpr(const CastExpr *CE) { if (!FromT || !ToT) return false; - if (!this->isValidBitCast(CE) && - !this->emitInvalidCast(CastKind::ReinterpretLike, /*Fatal=*/false, CE)) - return false; - assert(isPtrType(*FromT)); assert(isPtrType(*ToT)); + bool SrcIsVoidPtr = SubExprTy->isVoidPointerType(); if (FromT == ToT) { if (CE->getType()->isVoidPointerType() && !SubExprTy->isFunctionPointerType()) { @@ -520,6 +504,10 @@ bool Compiler::VisitCastExpr(const CastExpr *CE) { if (!this->visit(SubExpr)) return false; + if (!this->emitCheckBitCast(CETy->getPointeeType().getTypePtr(), + SrcIsVoidPtr, CE)) + return false; + if (CE->getType()->isFunctionPointerType() || SubExprTy->isFunctionPointerType()) { return this->emitFnPtrCast(CE); diff --git a/clang/lib/AST/ByteCode/Compiler.h b/clang/lib/AST/ByteCode/Compiler.h index fac0a7f4e1886..5c46f75af4da3 100644 --- a/clang/lib/AST/ByteCode/Compiler.h +++ b/clang/lib/AST/ByteCode/Compiler.h @@ -425,8 +425,6 @@ class Compiler : public ConstStmtVisitor, bool>, bool refersToUnion(const Expr *E); - bool isValidBitCast(const CastExpr *E); - protected: /// Variable to storage mapping. llvm::DenseMap Locals; diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h index c16408cef1fde..cbd60c9f2b37c 100644 --- a/clang/lib/AST/ByteCode/Interp.h +++ b/clang/lib/AST/ByteCode/Interp.h @@ -3290,6 +3290,52 @@ inline bool SideEffect(InterpState &S, CodePtr OpPC) { return S.noteSideEffect(); } +inline bool CheckBitCast(InterpState &S, CodePtr OpPC, const Type *TargetType, + bool SrcIsVoidPtr) { + const auto &Ptr = S.Stk.peek(); + if (Ptr.isZero()) + return true; + if (!Ptr.isBlockPointer()) + return true; + + if (TargetType->isIntegerType()) + return true; + + if (SrcIsVoidPtr && S.getLangOpts().CPlusPlus) { + bool HasValidResult = !Ptr.isZero(); + + if (HasValidResult) { + if (S.getStdAllocatorCaller("allocate")) + return true; + + const auto &E = cast(S.Current->getExpr(OpPC)); + if (S.getLangOpts().CPlusPlus26 && + S.getASTContext().hasSimilarType(Ptr.getType(), + QualType(TargetType, 0))) + return true; + + S.CCEDiag(E, diag::note_constexpr_invalid_void_star_cast) + << E->getSubExpr()->getType() << S.getLangOpts().CPlusPlus26 + << Ptr.getType().getCanonicalType() << E->getType()->getPointeeType(); + } else if (!S.getLangOpts().CPlusPlus26) { + const SourceInfo &E = S.Current->getSource(OpPC); + S.CCEDiag(E, diag::note_constexpr_invalid_cast) + << diag::ConstexprInvalidCastKind::CastFrom << "'void *'" + << S.Current->getRange(OpPC); + } + } + + QualType PtrType = Ptr.getType(); + if (PtrType->isRecordType() && + PtrType->getAsRecordDecl() != TargetType->getAsRecordDecl()) { + S.CCEDiag(S.Current->getSource(OpPC), diag::note_constexpr_invalid_cast) + << diag::ConstexprInvalidCastKind::ThisConversionOrReinterpret + << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC); + return false; + } + return true; +} + /// Same here, but only for casts. inline bool InvalidCast(InterpState &S, CodePtr OpPC, CastKind Kind, bool Fatal) { diff --git a/clang/lib/AST/ByteCode/Opcodes.td b/clang/lib/AST/ByteCode/Opcodes.td index a2eaa61ea4306..1785fcf4a7b20 100644 --- a/clang/lib/AST/ByteCode/Opcodes.td +++ b/clang/lib/AST/ByteCode/Opcodes.td @@ -422,8 +422,8 @@ def CheckLiteralType : Opcode { } def CheckArraySize : Opcode { let Args = [ArgUint64]; } - def CheckFunctionDecl : Opcode { let Args = [ArgFunctionDecl]; } +def CheckBitCast : Opcode { let Args = [ArgTypePtr, ArgBool]; } // [] -> [Value] def GetGlobal : AccessOpcode; diff --git a/clang/test/AST/ByteCode/cxx11.cpp b/clang/test/AST/ByteCode/cxx11.cpp index 753e51dfbfc1c..95615350f5142 100644 --- a/clang/test/AST/ByteCode/cxx11.cpp +++ b/clang/test/AST/ByteCode/cxx11.cpp @@ -387,3 +387,14 @@ struct Counter { // Passing an lvalue by value makes a non-elidable copy. constexpr int PassByValue(Counter c) { return c.copies; } static_assert(PassByValue(Counter(0)) == 0, "expect no copies"); + +namespace PointerCast { + /// The two interpreters disagree here. + struct S { int x, y; } s; + constexpr S* sptr = &s; + struct U {}; + struct Str { + int e : (Str*)(sptr) == (Str*)(sptr); // expected-error {{not an integral constant expression}} \ + // expected-note {{cast that performs the conversions of a reinterpret_cast}} + }; +} diff --git a/clang/test/AST/ByteCode/invalid.cpp b/clang/test/AST/ByteCode/invalid.cpp index 1f2d6bc1d48eb..115c8663079a1 100644 --- a/clang/test/AST/ByteCode/invalid.cpp +++ b/clang/test/AST/ByteCode/invalid.cpp @@ -88,4 +88,22 @@ namespace InvalidBitCast { // both-note {{in call to}} + struct sockaddr + { + char sa_data[8]; + }; + struct in_addr + { + unsigned int s_addr; + }; + struct sockaddr_in + { + unsigned short int sin_port; + struct in_addr sin_addr; + }; + /// Bitcast from sockaddr to sockaddr_in. Used to crash. + unsigned int get_addr(sockaddr addr) { + return ((sockaddr_in *)&addr)->sin_addr.s_addr; + } + }