Timm =?utf-8?q?Bäder?= <[email protected]>, Timm =?utf-8?q?Bäder?= <[email protected]> Message-ID: In-Reply-To: <llvm.org/llvm/llvm-project/pull/[email protected]>
https://github.com/tbaederr updated https://github.com/llvm/llvm-project/pull/183706 >From 2572b6d2967a0ab5954fcc06f6566416a3d173cc Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <[email protected]> Date: Mon, 16 Feb 2026 08:25:42 +0100 Subject: [PATCH 1/3] EvalSettings --- clang/lib/AST/ByteCode/ByteCodeEmitter.h | 1 + clang/lib/AST/ByteCode/Compiler.cpp | 16 +- clang/lib/AST/ByteCode/Context.cpp | 109 ++++-- clang/lib/AST/ByteCode/Context.h | 38 +- clang/lib/AST/ByteCode/EvalEmitter.cpp | 41 +- clang/lib/AST/ByteCode/EvalEmitter.h | 18 +- clang/lib/AST/ByteCode/EvalSettings.h | 35 ++ clang/lib/AST/ByteCode/EvaluationResult.cpp | 362 +++++++++++++++++- clang/lib/AST/ByteCode/EvaluationResult.h | 33 +- clang/lib/AST/ByteCode/Interp.cpp | 2 + clang/lib/AST/ByteCode/InterpState.cpp | 27 +- clang/lib/AST/ByteCode/InterpState.h | 9 +- clang/lib/AST/ExprConstShared.h | 43 +++ clang/lib/AST/ExprConstant.cpp | 267 ++++++------- .../ByteCode/codegen-constexpr-unknown.cpp | 8 +- clang/test/AST/ByteCode/unused-variables.cpp | 87 +++++ clang/test/CodeGenCXX/global-init.cpp | 8 + clang/test/SemaCXX/PR19955.cpp | 3 + 18 files changed, 869 insertions(+), 238 deletions(-) create mode 100644 clang/lib/AST/ByteCode/EvalSettings.h create mode 100644 clang/test/AST/ByteCode/unused-variables.cpp diff --git a/clang/lib/AST/ByteCode/ByteCodeEmitter.h b/clang/lib/AST/ByteCode/ByteCodeEmitter.h index dd18341d52a09..c5bd3b494c8df 100644 --- a/clang/lib/AST/ByteCode/ByteCodeEmitter.h +++ b/clang/lib/AST/ByteCode/ByteCodeEmitter.h @@ -62,6 +62,7 @@ class ByteCodeEmitter { /// We're always emitting bytecode. bool isActive() const { return true; } bool checkingForUndefinedBehavior() const { return false; } + bool constantFolding() const { return false; } /// Callback for local registration. Local createLocal(Descriptor *D); diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index 70d3d80b806d1..b7dbea539d48f 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -2985,6 +2985,9 @@ bool Compiler<Emitter>::VisitMaterializeTemporaryExpr( // the temporary is explicitly static, create a global variable. OptPrimType SubExprT = classify(SubExpr); if (E->getStorageDuration() == SD_Static) { + if (this->constantFolding()) + return false; + UnsignedOrNone GlobalIndex = P.createGlobal(E); if (!GlobalIndex) return false; @@ -4823,6 +4826,9 @@ const Function *Compiler<Emitter>::getFunction(const FunctionDecl *FD) { template <class Emitter> bool Compiler<Emitter>::visitExpr(const Expr *E, bool DestroyToplevelScope) { + if (E->getType().isNull()) + return false; + LocalScope<Emitter> RootScope(this, ScopeKind::FullExpression); // If we won't destroy the toplevel scope, check for memory leaks first. @@ -7250,10 +7256,10 @@ bool Compiler<Emitter>::visitDeclRef(const ValueDecl *D, const Expr *E) { } // In case we need to re-visit a declaration. - auto revisit = [&](const VarDecl *VD) -> bool { + auto revisit = [&](const VarDecl *VD, bool ConstexprUnknown = true) -> bool { if (!this->emitPushCC(VD->hasConstantInitialization(), E)) return false; - auto VarState = this->visitDecl(VD, /*IsConstexprUnknown=*/true); + auto VarState = this->visitDecl(VD, ConstexprUnknown); if (!this->emitPopCC(E)) return false; @@ -7299,7 +7305,7 @@ bool Compiler<Emitter>::visitDeclRef(const ValueDecl *D, const Expr *E) { if (!Ctx.getLangOpts().CPlusPlus) { if (VD->getAnyInitializer() && DeclType.isConstant(Ctx.getASTContext()) && !VD->isWeak()) - return revisit(VD); + return revisit(VD, DeclType->isPointerType()); return this->emitDummyPtr(D, E); } @@ -7333,10 +7339,12 @@ bool Compiler<Emitter>::visitDeclRef(const ValueDecl *D, const Expr *E) { if (VD->isLocalVarDecl() && typeShouldBeVisited(DeclType) && VD->getInit() && !VD->getInit()->isValueDependent()) { if (VD->evaluateValue()) { + bool ConstexprUnknown = !DeclType.isConstant(Ctx.getASTContext()) && + !DeclType->isReferenceType(); // Revisit the variable declaration, but make sure it's associated with a // different evaluation, so e.g. mutable reads don't work on it. EvalIDScope _(Ctx); - return revisit(VD); + return revisit(VD, ConstexprUnknown); } if (IsReference) diff --git a/clang/lib/AST/ByteCode/Context.cpp b/clang/lib/AST/ByteCode/Context.cpp index 879d51e6a2c3e..3fbfc114857f4 100644 --- a/clang/lib/AST/ByteCode/Context.cpp +++ b/clang/lib/AST/ByteCode/Context.cpp @@ -36,7 +36,8 @@ Context::Context(ASTContext &Ctx) : Ctx(Ctx), P(new Program(*this)) { Context::~Context() {} -bool Context::isPotentialConstantExpr(State &Parent, const FunctionDecl *FD) { +bool Context::isPotentialConstantExpr(const EvalSettings &Settings, + const FunctionDecl *FD) { assert(Stk.empty()); // Get a function handle. @@ -53,15 +54,16 @@ bool Context::isPotentialConstantExpr(State &Parent, const FunctionDecl *FD) { ++EvalID; // And run it. - return Run(Parent, Func); + return Run(Settings, Func); } -void Context::isPotentialConstantExprUnevaluated(State &Parent, const Expr *E, +void Context::isPotentialConstantExprUnevaluated(const EvalSettings &Settings, + const Expr *E, const FunctionDecl *FD) { assert(Stk.empty()); ++EvalID; size_t StackSizeBefore = Stk.size(); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); if (!C.interpretCall(FD, E)) { C.cleanup(); @@ -75,7 +77,37 @@ bool Context::evaluateAsRValue(State &Parent, const Expr *E, APValue &Result) { size_t StackSizeBefore = Stk.size(); Compiler<EvalEmitter> C(*this, *P, Parent, Stk); - auto Res = C.interpretExpr(E, /*ConvertResultToRValue=*/E->isGLValue()); + auto Res = C.interpretExpr(E); + + if (Res.isInvalid()) { + C.cleanup(); + Stk.clearTo(StackSizeBefore); + return false; + } + + if (!Recursing) { + // We *can* actually get here with a non-empty stack, since + // things like InterpState::noteSideEffect() exist. + C.cleanup(); +#ifndef NDEBUG + // Make sure we don't rely on some value being still alive in + // InterpStack memory. + Stk.clearTo(StackSizeBefore); +#endif + } + + Result = Res.stealAPValue(); + return true; +} + +bool Context::evaluateAsRValue(const EvalSettings &Settings, const Expr *E, + APValue &Result) { + ++EvalID; + bool Recursing = !Stk.empty(); + size_t StackSizeBefore = Stk.size(); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); + + auto Res = C.interpretExpr(E); if (Res.isInvalid()) { C.cleanup(); @@ -99,12 +131,12 @@ bool Context::evaluateAsRValue(State &Parent, const Expr *E, APValue &Result) { return true; } -bool Context::evaluate(State &Parent, const Expr *E, APValue &Result, - ConstantExprKind Kind) { +bool Context::evaluate(const EvalSettings &Settings, const Expr *E, + APValue &Result) { ++EvalID; bool Recursing = !Stk.empty(); size_t StackSizeBefore = Stk.size(); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); auto Res = C.interpretExpr(E, /*ConvertResultToRValue=*/false, /*DestroyToplevelScope=*/true); @@ -128,16 +160,17 @@ bool Context::evaluate(State &Parent, const Expr *E, APValue &Result, return true; } -bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD, - const Expr *Init, APValue &Result) { +bool Context::evaluateAsInitializer(const EvalSettings &Settings, + const VarDecl *VD, const Expr *Init, + APValue &Result) { ++EvalID; bool Recursing = !Stk.empty(); size_t StackSizeBefore = Stk.size(); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); bool CheckGlobalInitialized = - shouldBeGloballyIndexed(VD) && (VD->getType()->isRecordType() || VD->getType()->isArrayType()); + auto Res = C.interpretDecl(VD, Init, CheckGlobalInitialized); if (Res.isInvalid()) { C.cleanup(); @@ -161,21 +194,23 @@ bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD, } template <typename ResultT> -bool Context::evaluateStringRepr(State &Parent, const Expr *SizeExpr, - const Expr *PtrExpr, ResultT &Result) { +bool Context::evaluateStringRepr(const EvalSettings &Settings, + const Expr *SizeExpr, const Expr *PtrExpr, + ResultT &Result) { assert(Stk.empty()); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); // Evaluate size value. APValue SizeValue; - if (!evaluateAsRValue(Parent, SizeExpr, SizeValue)) + if (!evaluateAsRValue(Settings, SizeExpr, SizeValue)) return false; if (!SizeValue.isInt()) return false; uint64_t Size = SizeValue.getInt().getZExtValue(); - auto PtrRes = C.interpretAsPointer(PtrExpr, [&](const Pointer &Ptr) { + auto PtrRes = C.interpretAsPointer(PtrExpr, [&](InterpState &S, + const Pointer &Ptr) { if (Size == 0) { if constexpr (std::is_same_v<ResultT, APValue>) Result = APValue(APValue::UninitArray{}, 0, 0); @@ -190,7 +225,7 @@ bool Context::evaluateStringRepr(State &Parent, const Expr *SizeExpr, return false; if (Size > Ptr.getNumElems()) { - Parent.FFDiag(SizeExpr, diag::note_constexpr_access_past_end) << AK_Read; + S.FFDiag(SizeExpr, diag::note_constexpr_access_past_end) << AK_Read; Size = Ptr.getNumElems(); } @@ -223,28 +258,30 @@ bool Context::evaluateStringRepr(State &Parent, const Expr *SizeExpr, return true; } -bool Context::evaluateCharRange(State &Parent, const Expr *SizeExpr, - const Expr *PtrExpr, APValue &Result) { +bool Context::evaluateCharRange(const EvalSettings &Settings, + const Expr *SizeExpr, const Expr *PtrExpr, + APValue &Result) { assert(SizeExpr); assert(PtrExpr); - return evaluateStringRepr(Parent, SizeExpr, PtrExpr, Result); + return evaluateStringRepr(Settings, SizeExpr, PtrExpr, Result); } -bool Context::evaluateCharRange(State &Parent, const Expr *SizeExpr, - const Expr *PtrExpr, std::string &Result) { +bool Context::evaluateCharRange(const EvalSettings &Settings, + const Expr *SizeExpr, const Expr *PtrExpr, + std::string &Result) { assert(SizeExpr); assert(PtrExpr); - return evaluateStringRepr(Parent, SizeExpr, PtrExpr, Result); + return evaluateStringRepr(Settings, SizeExpr, PtrExpr, Result); } -bool Context::evaluateString(State &Parent, const Expr *E, +bool Context::evaluateString(const EvalSettings &Settings, const Expr *E, std::string &Result) { assert(Stk.empty()); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); - auto PtrRes = C.interpretAsPointer(E, [&](const Pointer &Ptr) { + auto PtrRes = C.interpretAsPointer(E, [&](InterpState &, const Pointer &Ptr) { if (!Ptr.isBlockPointer()) return false; @@ -288,12 +325,13 @@ bool Context::evaluateString(State &Parent, const Expr *E, return true; } -std::optional<uint64_t> Context::evaluateStrlen(State &Parent, const Expr *E) { +std::optional<uint64_t> Context::evaluateStrlen(const EvalSettings &Settings, + const Expr *E) { assert(Stk.empty()); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); std::optional<uint64_t> Result; - auto PtrRes = C.interpretAsPointer(E, [&](const Pointer &Ptr) { + auto PtrRes = C.interpretAsPointer(E, [&](InterpState &, const Pointer &Ptr) { if (!Ptr.isBlockPointer()) return false; @@ -335,13 +373,14 @@ std::optional<uint64_t> Context::evaluateStrlen(State &Parent, const Expr *E) { } std::optional<uint64_t> -Context::tryEvaluateObjectSize(State &Parent, const Expr *E, unsigned Kind) { +Context::tryEvaluateObjectSize(const EvalSettings &Settings, const Expr *E, + unsigned Kind) { assert(Stk.empty()); - Compiler<EvalEmitter> C(*this, *P, Parent, Stk); + Compiler<EvalEmitter> C(*this, *P, Settings, Stk); std::optional<uint64_t> Result; - auto PtrRes = C.interpretAsPointer(E, [&](const Pointer &Ptr) { + auto PtrRes = C.interpretAsPointer(E, [&](InterpState &, const Pointer &Ptr) { const Descriptor *DeclDesc = Ptr.getDeclDesc(); if (!DeclDesc) return false; @@ -490,8 +529,8 @@ const llvm::fltSemantics &Context::getFloatSemantics(QualType T) const { return Ctx.getFloatTypeSemantics(T); } -bool Context::Run(State &Parent, const Function *Func) { - InterpState State(Parent, *P, Stk, *this, Func); +bool Context::Run(const EvalSettings &Settings, const Function *Func) { + InterpState State(Settings, *P, Stk, *this, Func); if (Interpret(State)) { assert(Stk.empty()); return true; diff --git a/clang/lib/AST/ByteCode/Context.h b/clang/lib/AST/ByteCode/Context.h index 1b8c25732a262..b1e15859a5d3f 100644 --- a/clang/lib/AST/ByteCode/Context.h +++ b/clang/lib/AST/ByteCode/Context.h @@ -16,6 +16,7 @@ #ifndef LLVM_CLANG_AST_INTERP_CONTEXT_H #define LLVM_CLANG_AST_INTERP_CONTEXT_H +#include "EvalSettings.h" #include "InterpStack.h" #include "clang/AST/ASTContext.h" @@ -48,33 +49,40 @@ class Context final { ~Context(); /// Checks if a function is a potential constant expression. - bool isPotentialConstantExpr(State &Parent, const FunctionDecl *FD); - void isPotentialConstantExprUnevaluated(State &Parent, const Expr *E, + bool isPotentialConstantExpr(const EvalSettings &Settings, + const FunctionDecl *FD); + void isPotentialConstantExprUnevaluated(const EvalSettings &Settings, + const Expr *E, const FunctionDecl *FD); - /// Evaluates a toplevel expression as an rvalue. + // FIXME: Get rid of this version and switch to the one taking + // EvalSettings always. bool evaluateAsRValue(State &Parent, const Expr *E, APValue &Result); + /// Evaluates a toplevel expression as an rvalue. + bool evaluateAsRValue(const EvalSettings &Settings, const Expr *E, + APValue &Result); /// Like evaluateAsRvalue(), but does no implicit lvalue-to-rvalue conversion. - bool evaluate(State &Parent, const Expr *E, APValue &Result, - ConstantExprKind Kind); + bool evaluate(const EvalSettings &Settings, const Expr *E, APValue &Result); /// Evaluates a toplevel initializer. - bool evaluateAsInitializer(State &Parent, const VarDecl *VD, const Expr *Init, - APValue &Result); + bool evaluateAsInitializer(const EvalSettings &Settings, const VarDecl *VD, + const Expr *Init, APValue &Result); - bool evaluateCharRange(State &Parent, const Expr *SizeExpr, + bool evaluateCharRange(const EvalSettings &Settings, const Expr *SizeExpr, const Expr *PtrExpr, APValue &Result); - bool evaluateCharRange(State &Parent, const Expr *SizeExpr, + bool evaluateCharRange(const EvalSettings &Settings, const Expr *SizeExpr, const Expr *PtrExpr, std::string &Result); /// Evaluate \param E and if it can be evaluated to a null-terminated string, /// copy the result into \param Result. - bool evaluateString(State &Parent, const Expr *E, std::string &Result); + bool evaluateString(const EvalSettings &Settings, const Expr *E, + std::string &Result); /// Evalute \param E and if it can be evaluated to a string literal, /// run strlen() on it. - std::optional<uint64_t> evaluateStrlen(State &Parent, const Expr *E); + std::optional<uint64_t> evaluateStrlen(const EvalSettings &Settings, + const Expr *E); /// If \param E evaluates to a pointer the number of accessible bytes /// past the pointer is estimated in \param Result as if evaluated by @@ -86,8 +94,8 @@ class Context final { /// as the one referred to by E are considered, when Kind & 1 == 0 /// bytes belonging to the same storage (stack, heap allocation, /// global variable) are considered. - std::optional<uint64_t> tryEvaluateObjectSize(State &Parent, const Expr *E, - unsigned Kind); + std::optional<uint64_t> tryEvaluateObjectSize(const EvalSettings &Setgings, + const Expr *E, unsigned Kind); /// Returns the AST context. ASTContext &getASTContext() const { return Ctx; } @@ -170,10 +178,10 @@ class Context final { private: friend class EvalIDScope; /// Runs a function. - bool Run(State &Parent, const Function *Func); + bool Run(const EvalSettings &Settings, const Function *Func); template <typename ResultT> - bool evaluateStringRepr(State &Parent, const Expr *SizeExpr, + bool evaluateStringRepr(const EvalSettings &Settings, const Expr *SizeExpr, const Expr *PtrExpr, ResultT &Result); /// Current compilation context. diff --git a/clang/lib/AST/ByteCode/EvalEmitter.cpp b/clang/lib/AST/ByteCode/EvalEmitter.cpp index ee168a82d20a2..d18ec7103e206 100644 --- a/clang/lib/AST/ByteCode/EvalEmitter.cpp +++ b/clang/lib/AST/ByteCode/EvalEmitter.cpp @@ -11,14 +11,21 @@ #include "IntegralAP.h" #include "Interp.h" #include "clang/AST/DeclCXX.h" +#include "clang/AST/ExprCXX.h" using namespace clang; using namespace clang::interp; +// FIXME: Get rid of this constructor. EvalEmitter::EvalEmitter(Context &Ctx, Program &P, State &Parent, InterpStack &Stk) : Ctx(Ctx), P(P), S(Parent, P, Stk, Ctx, this), EvalResult(&Ctx) {} +EvalEmitter::EvalEmitter(Context &Ctx, Program &P, const EvalSettings &Settings, + InterpStack &Stk) + : Ctx(Ctx), P(P), S(Settings, P, Stk, Ctx, this), EvalResult(&Ctx), + ConstexprKind(Settings.ConstexprKind) {} + EvalEmitter::~EvalEmitter() { for (auto &V : Locals) { Block *B = reinterpret_cast<Block *>(V.get()); @@ -106,7 +113,7 @@ EvalEmitter::LabelTy EvalEmitter::getLabel() { return NextLabel++; } Scope::Local EvalEmitter::createLocal(Descriptor *D) { // Allocate memory for a local. auto Memory = std::make_unique<char[]>(sizeof(Block) + D->getAllocSize()); - auto *B = new (Memory.get()) Block(Ctx.getEvalID(), D, /*isStatic=*/false); + auto *B = new (Memory.get()) Block(Ctx.getEvalID(), D, /*IsStatic=*/false); B->invokeCtor(); // Initialize local variable inline descriptor. @@ -188,6 +195,18 @@ template <PrimType OpType> bool EvalEmitter::emitRet(SourceInfo Info) { return true; } +template <> bool EvalEmitter::emitRet<PT_MemberPtr>(SourceInfo Info) { + if (!isActive()) + return true; + + const MemberPointer &MP = S.Stk.pop<MemberPointer>(); + if (!EvalResult.checkMemberPointer(S, MP, Info, ConstexprKind)) + return false; + + EvalResult.takeValue(MP.toAPValue(Ctx.getASTContext())); + return true; +} + template <> bool EvalEmitter::emitRet<PT_Ptr>(SourceInfo Info) { if (!isActive()) return true; @@ -195,15 +214,19 @@ template <> bool EvalEmitter::emitRet<PT_Ptr>(SourceInfo Info) { const Pointer &Ptr = S.Stk.pop<Pointer>(); // If we're returning a raw pointer, call our callback. if (this->PtrCB) - return (*this->PtrCB)(Ptr); + return (*this->PtrCB)(S, Ptr); - if (!EvalResult.checkReturnValue(S, Ctx, Ptr, Info)) + if (!EvalResult.checkDynamicAllocations(S, Ctx, Ptr, Info)) return false; + if (CheckFullyInitialized && !EvalResult.checkFullyInitialized(S, Ptr)) return false; - // Function pointers are alway returned as lvalues. + // Function pointers are always returned as lvalues. if (Ptr.isFunctionPointer()) { + if (!EvalResult.checkFunctionPointer(S, Ptr, Info, ConstexprKind)) + return false; + EvalResult.takeValue(Ptr.toAPValue(Ctx.getASTContext())); return true; } @@ -225,6 +248,9 @@ template <> bool EvalEmitter::emitRet<PT_Ptr>(SourceInfo Info) { Ptr.block()->getEvalID() != Ctx.getEvalID()) return false; + if (!EvalResult.checkLValueFields(S, Ptr, Info, ConstexprKind)) + return false; + if (std::optional<APValue> V = Ptr.toRValue(Ctx, EvalResult.getSourceType())) { EvalResult.takeValue(std::move(*V)); @@ -232,6 +258,8 @@ template <> bool EvalEmitter::emitRet<PT_Ptr>(SourceInfo Info) { return false; } } else { + if (!EvalResult.checkLValue(S, Ptr, Info, ConstexprKind)) + return false; // If this is pointing to a local variable, just return // the result, even if the pointer is dead. // This will later be diagnosed by CheckLValueConstantExpression. @@ -257,10 +285,12 @@ bool EvalEmitter::emitRetVoid(SourceInfo Info) { bool EvalEmitter::emitRetValue(SourceInfo Info) { const auto &Ptr = S.Stk.pop<Pointer>(); - if (!EvalResult.checkReturnValue(S, Ctx, Ptr, Info)) + if (!EvalResult.checkDynamicAllocations(S, Ctx, Ptr, Info)) return false; if (CheckFullyInitialized && !EvalResult.checkFullyInitialized(S, Ptr)) return false; + if (!EvalResult.checkLValueFields(S, Ptr, Info, ConstexprKind)) + return false; if (std::optional<APValue> APV = Ptr.toRValue(S.getASTContext(), EvalResult.getSourceType())) { @@ -275,7 +305,6 @@ bool EvalEmitter::emitRetValue(SourceInfo Info) { bool EvalEmitter::emitGetPtrLocal(uint32_t I, SourceInfo Info) { if (!isActive()) return true; - Block *B = getLocal(I); S.Stk.push<Pointer>(B, sizeof(InlineDescriptor)); return true; diff --git a/clang/lib/AST/ByteCode/EvalEmitter.h b/clang/lib/AST/ByteCode/EvalEmitter.h index a9f87db5d7f8d..045512c5582eb 100644 --- a/clang/lib/AST/ByteCode/EvalEmitter.h +++ b/clang/lib/AST/ByteCode/EvalEmitter.h @@ -33,11 +33,16 @@ class EvalEmitter : public SourceMapper { using LabelTy = uint32_t; using AddrTy = uintptr_t; using Local = Scope::Local; - using PtrCallback = llvm::function_ref<bool(const Pointer &)>; + using PtrCallback = llvm::function_ref<bool(InterpState &, const Pointer &)>; - EvaluationResult interpretExpr(const Expr *E, - bool ConvertResultToRValue = false, + EvaluationResult interpretExpr(const Expr *E) { + return interpretExpr(E, /*ConvertResultToRValue=*/E->isGLValue(), + /*DestroyToplevelScope=*/false); + } + + EvaluationResult interpretExpr(const Expr *E, bool ConvertResultToRValue, bool DestroyToplevelScope = false); + EvaluationResult interpretDecl(const VarDecl *VD, const Expr *Init, bool CheckFullyInitialized); /// Interpret the given Expr to a Pointer. @@ -49,8 +54,14 @@ class EvalEmitter : public SourceMapper { /// Clean up all resources. void cleanup(); + bool constantFolding() const { + return S.EvalMode == EvaluationMode::ConstantFold; + } + protected: EvalEmitter(Context &Ctx, Program &P, State &Parent, InterpStack &Stk); + EvalEmitter(Context &Ctx, Program &P, const EvalSettings &Settings, + InterpStack &Stk); virtual ~EvalEmitter(); @@ -109,6 +120,7 @@ class EvalEmitter : public SourceMapper { InterpState S; /// Location to write the result to. EvaluationResult EvalResult; + ConstantExprKind ConstexprKind = ConstantExprKind::Normal; /// Whether the result should be converted to an RValue. bool ConvertResultToRValue = false; /// Whether we should check if the result has been fully diff --git a/clang/lib/AST/ByteCode/EvalSettings.h b/clang/lib/AST/ByteCode/EvalSettings.h new file mode 100644 index 0000000000000..df4dcda515ded --- /dev/null +++ b/clang/lib/AST/ByteCode/EvalSettings.h @@ -0,0 +1,35 @@ +//===--------------------------- EvalSettings.h -----------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_AST_INTERP_EVALSETTINGS_H +#define LLVM_CLANG_AST_INTERP_EVALSETTINGS_H + +#include "State.h" + +namespace clang { +namespace interp { + +struct EvalSettings { + Expr::EvalStatus &EvalStatus; + const EvaluationMode EvalMode; + const ConstantExprKind ConstexprKind; + + bool InConstantContext = false; + bool CheckingPotentialConstantExpression = false; + bool CheckingForUndefinedBehavior = false; + + EvalSettings(EvaluationMode EvalMode, Expr::EvalStatus &EvalStatus, + ConstantExprKind ConstexprKind = ConstantExprKind::Normal) + : EvalStatus(EvalStatus), EvalMode(EvalMode), + ConstexprKind(ConstexprKind) {} +}; + +} // namespace interp +} // namespace clang + +#endif diff --git a/clang/lib/AST/ByteCode/EvaluationResult.cpp b/clang/lib/AST/ByteCode/EvaluationResult.cpp index 039848f00764e..ddc3470ae86bd 100644 --- a/clang/lib/AST/ByteCode/EvaluationResult.cpp +++ b/clang/lib/AST/ByteCode/EvaluationResult.cpp @@ -7,16 +7,36 @@ //===----------------------------------------------------------------------===// #include "EvaluationResult.h" +#include "../ExprConstShared.h" #include "InterpState.h" #include "Pointer.h" #include "Record.h" +#include "clang/AST/DeclTemplate.h" +#include "clang/AST/Expr.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/ExprObjC.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SetVector.h" +#include "llvm/ADT/SmallPtrSet.h" #include <iterator> namespace clang { namespace interp { +QualType EvaluationResult::getStorageType() const { + if (const auto *E = Source.dyn_cast<const Expr *>()) { + if (E->isPRValue()) + return E->getType(); + + return Ctx->getASTContext().getLValueReferenceType(E->getType()); + } + + if (const auto *D = + dyn_cast_if_present<ValueDecl>(Source.dyn_cast<const Decl *>())) + return D->getType(); + return QualType(); +} + static void DiagnoseUninitializedSubobject(InterpState &S, SourceLocation Loc, const FieldDecl *SubObjDecl) { assert(SubObjDecl && "Subobject declaration does not exist"); @@ -210,9 +230,10 @@ static void collectBlocks(const Pointer &Ptr, } } -bool EvaluationResult::checkReturnValue(InterpState &S, const Context &Ctx, - const Pointer &Ptr, - const SourceInfo &Info) { +bool EvaluationResult::checkDynamicAllocations(InterpState &S, + const Context &Ctx, + const Pointer &Ptr, + SourceInfo Info) { // Collect all blocks that this pointer (transitively) points to and // return false if any of them is a dynamic block. llvm::SetVector<const Block *> Blocks; @@ -236,5 +257,340 @@ bool EvaluationResult::checkReturnValue(InterpState &S, const Context &Ctx, return true; } +static bool isGlobalLValue(const Pointer &Ptr) { + if (Ptr.isBlockPointer() && Ptr.block()->isDynamic()) + return true; + if (Ptr.isTypeidPointer()) + return true; + + const Descriptor *Desc = Ptr.getDeclDesc(); + return ::isGlobalLValue(Desc->asValueDecl(), Desc->asExpr()); +} + +/// Check if the given function pointer can be returned from an evaluation. +static bool checkFunctionPtr(InterpState &S, const Pointer &Ptr, + QualType PtrType, SourceInfo Info, + ConstantExprKind ConstexprKind) { + assert(Ptr.isFunctionPointer()); + const FunctionPointer &FuncPtr = Ptr.asFunctionPointer(); + const FunctionDecl *FD = FuncPtr.getFunction()->getDecl(); + // E.g. ObjC block pointers. + if (!FD) + return true; + if (FD->isImmediateFunction()) { + S.FFDiag(Info, diag::note_consteval_address_accessible) + << !PtrType->isAnyPointerType(); + S.Note(FD->getLocation(), diag::note_declared_at); + return false; + } + + // __declspec(dllimport) must be handled very carefully: + // We must never initialize an expression with the thunk in C++. + // Doing otherwise would allow the same id-expression to yield + // different addresses for the same function in different translation + // units. However, this means that we must dynamically initialize the + // expression with the contents of the import address table at runtime. + // + // The C language has no notion of ODR; furthermore, it has no notion of + // dynamic initialization. This means that we are permitted to + // perform initialization with the address of the thunk. + if (S.getLangOpts().CPlusPlus && !isForManglingOnly(ConstexprKind) && + FD->hasAttr<DLLImportAttr>()) + // FIXME: Diagnostic! + return false; + return true; +} + +static bool lvalFields(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, + QualType PtrType, SourceInfo Info, + ConstantExprKind ConstexprKind, + llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks); +static bool lval(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, + QualType PtrType, SourceInfo Info, + ConstantExprKind ConstexprKind, + llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks) { + if (Ptr.isFunctionPointer()) + return checkFunctionPtr(S, Ptr, PtrType, Info, ConstexprKind); + + if (!Ptr.isBlockPointer()) + return true; + + const Descriptor *DeclDesc = Ptr.block()->getDescriptor(); + const Expr *BaseE = DeclDesc->asExpr(); + const ValueDecl *BaseVD = DeclDesc->asValueDecl(); + assert(BaseE || BaseVD); + bool IsReferenceType = PtrType->isReferenceType(); + bool IsSubObj = !Ptr.isRoot() || (Ptr.inArray() && !Ptr.isArrayRoot()); + + if (!isGlobalLValue(Ptr)) { + if (S.getLangOpts().CPlusPlus11) { + S.FFDiag(Info, diag::note_constexpr_non_global, 1) + << IsReferenceType << IsSubObj + << !!DeclDesc->asValueDecl() // DeclDesc->IsTemporary + << DeclDesc->asValueDecl(); + const VarDecl *VarD = DeclDesc->asVarDecl(); + if (VarD && VarD->isConstexpr()) { + // Non-static local constexpr variables have unintuitive semantics: + // constexpr int a = 1; + // constexpr const int *p = &a; + // ... is invalid because the address of 'a' is not constant. Suggest + // adding a 'static' in this case. + S.Note(VarD->getLocation(), diag::note_constexpr_not_static) + << VarD + << FixItHint::CreateInsertion(VarD->getBeginLoc(), "static "); + } else { + if (const ValueDecl *VD = DeclDesc->asValueDecl()) + S.Note(VD->getLocation(), diag::note_declared_at); + else if (const Expr *E = DeclDesc->asExpr()) + S.Note(E->getExprLoc(), diag::note_constexpr_temporary_here); + } + } else { + S.FFDiag(Info); + } + return false; + } + + if (const auto *VD = dyn_cast_if_present<VarDecl>(BaseVD)) { + // Check if this is a thread-local variable. + if (VD->getTLSKind()) { + // FIXME: Diagnostic! + return false; + } + + // A dllimport variable never acts like a constant, unless we're + // evaluating a value for use only in name mangling, and unless it's a + // static local. For the latter case, we'd still need to evaluate the + // constant expression in case we're inside a (inlined) function. + if (!isForManglingOnly(ConstexprKind) && VD->hasAttr<DLLImportAttr>() && + !VD->isStaticLocal()) + return false; + + // In CUDA/HIP device compilation, only device side variables have + // constant addresses. + if (S.getLangOpts().CUDA && S.getLangOpts().CUDAIsDevice && + Ctx.CUDAConstantEvalCtx.NoWrongSidedVars) { + if ((!VD->hasAttr<CUDADeviceAttr>() && !VD->hasAttr<CUDAConstantAttr>() && + !VD->getType()->isCUDADeviceBuiltinSurfaceType() && + !VD->getType()->isCUDADeviceBuiltinTextureType()) || + VD->hasAttr<HIPManagedAttr>()) + return false; + } + + return true; + } + + if (const auto *MTE = dyn_cast_if_present<MaterializeTemporaryExpr>(BaseE)) { + QualType TempType = Ptr.getType(); + + if (TempType.isDestructedType()) { + S.FFDiag(MTE->getExprLoc(), + diag::note_constexpr_unsupported_temporary_nontrivial_dtor) + << TempType; + return false; + } + + if (Ptr.getFieldDesc()->isPrimitive() && + Ptr.getFieldDesc()->getPrimType() == PT_Ptr) { + // Recurse! + Pointer Pointee = Ptr.deref<Pointer>(); + if (CheckedBlocks.insert(Pointee.block()).second) { + if (!lval(S, Ctx, Pointee, Pointee.getType(), + Ptr.getDeclDesc()->getLoc(), ConstexprKind, CheckedBlocks)) + return false; + } + } else if (Ptr.getRecord()) { + return lvalFields(S, Ctx, Ptr, Ptr.getType(), Info, + ConstantExprKind::Normal, CheckedBlocks); + } + } + + return true; +} + +static bool lvalFields(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, + QualType PtrType, SourceInfo Info, + ConstantExprKind ConstexprKind, + llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks) { + if (!Ptr.isBlockPointer()) + return true; + + const Descriptor *FieldDesc = Ptr.getFieldDesc(); + if (const Record *R = Ptr.getRecord()) { + for (const Record::Field &F : R->fields()) { + if (F.Desc->isPrimitive() && F.Desc->getPrimType() == PT_Ptr) { + QualType FieldType = F.Decl->getType(); + if (!Ptr.atField(F.Offset).isLive()) + return false; + + Pointer Pointee = Ptr.atField(F.Offset).deref<Pointer>(); + if (CheckedBlocks.insert(Pointee.block()).second) { + if (!lval(S, Ctx, Pointee, FieldType, Info, ConstexprKind, + CheckedBlocks)) + return false; + } + } else { + Pointer FieldPtr = Ptr.atField(F.Offset); + if (!lvalFields(S, Ctx, FieldPtr, F.Decl->getType(), Info, + ConstexprKind, CheckedBlocks)) + return false; + } + } + + for (const Record::Base &B : R->bases()) { + Pointer BasePtr = Ptr.atField(B.Offset); + if (!lvalFields(S, Ctx, BasePtr, B.Desc->getType(), Info, ConstexprKind, + CheckedBlocks)) + return false; + } + for (const Record::Base &B : R->virtual_bases()) { + Pointer BasePtr = Ptr.atField(B.Offset); + if (!lvalFields(S, Ctx, BasePtr, B.Desc->getType(), Info, ConstexprKind, + CheckedBlocks)) + return false; + } + + return true; + } + if (FieldDesc->isPrimitiveArray()) { + if (FieldDesc->getPrimType() == PT_Ptr) { + for (unsigned I = 0; I != FieldDesc->getNumElems(); ++I) { + if (!Ptr.isLive()) + return false; + Pointer Pointee = Ptr.elem<Pointer>(I); + if (CheckedBlocks.insert(Pointee.block()).second) { + if (!lval(S, Ctx, Pointee, FieldDesc->getElemQualType(), Info, + ConstexprKind, CheckedBlocks)) + return false; + } + } + } + return true; + } + if (FieldDesc->isCompositeArray()) { + for (unsigned I = 0; I != FieldDesc->getNumElems(); ++I) { + Pointer Elem = Ptr.atIndex(I).narrow(); + if (!lvalFields(S, Ctx, Elem, FieldDesc->getElemQualType(), Info, + ConstexprKind, CheckedBlocks)) + return false; + } + return true; + } + if (FieldDesc->isPrimitive() && FieldDesc->getPrimType() == PT_MemberPtr) { + MemberPointer MP = Ptr.deref<MemberPointer>(); + if (const CXXMethodDecl *MD = MP.getMemberFunction(); + MD && MD->isImmediateFunction()) { + S.FFDiag(Info, diag::note_consteval_address_accessible) + << !PtrType->isAnyPointerType(); + S.Note(MD->getLocation(), diag::note_declared_at); + return false; + } + } + + return true; +} + +/// Toplevel accessor to check all lvalue fields. +bool EvaluationResult::checkLValueFields(InterpState &S, const Pointer &Ptr, + SourceInfo Info, + ConstantExprKind ConstexprKind) { + QualType SourceType = getStorageType(); + llvm::SmallPtrSet<const Block *, 4> CheckedBlocks; + + return lvalFields(S, Ctx->getASTContext(), Ptr, SourceType, Info, + ConstexprKind, CheckedBlocks); +} + +bool EvaluationResult::checkLValue(InterpState &S, const Pointer &Ptr, + SourceInfo Info, + ConstantExprKind ConstexprKind) { + if (Ptr.isZero()) + return true; + + QualType SourceType = getStorageType(); + if (Ptr.isFunctionPointer()) + return checkFunctionPtr(S, Ptr, SourceType, Info, ConstexprKind); + + bool IsReferenceType = SourceType->isReferenceType(); + if (Ptr.isTypeidPointer()) { + if (isTemplateArgument(ConstexprKind)) { + int InvalidBaseKind = 0; + StringRef Ident; + S.FFDiag(Info, diag::note_constexpr_invalid_template_arg) + << IsReferenceType << false << InvalidBaseKind << Ident; + return false; + } + + return true; + } + + if (!Ptr.isBlockPointer()) + return true; + + const Descriptor *DeclDesc = Ptr.getDeclDesc(); + const Expr *BaseE = DeclDesc->asExpr(); + const ValueDecl *BaseVD = DeclDesc->asValueDecl(); + assert(BaseE || BaseVD); + bool IsSubObj = !Ptr.isRoot() || (Ptr.inArray() && !Ptr.isArrayRoot()); + + // Additional restrictions apply in a template argument. We only enforce the + // C++20 restrictions here; additional syntactic and semantic restrictions + // are applied elsewhere. + if (isTemplateArgument(ConstexprKind)) { + int InvalidBaseKind = -1; + StringRef Ident; + if (isa_and_nonnull<StringLiteral>(BaseE)) + InvalidBaseKind = 1; + else if (isa_and_nonnull<MaterializeTemporaryExpr>(BaseE) || + isa_and_nonnull<LifetimeExtendedTemporaryDecl>(BaseVD)) + InvalidBaseKind = 2; + else if (auto *PE = dyn_cast_if_present<PredefinedExpr>(BaseE)) { + InvalidBaseKind = 3; + Ident = PE->getIdentKindName(); + IsSubObj = true; + } + + if (InvalidBaseKind != -1) { + S.FFDiag(Info, diag::note_constexpr_invalid_template_arg) + << IsReferenceType << IsSubObj << InvalidBaseKind << Ident; + return false; + } + } + + llvm::SmallPtrSet<const Block *, 4> CheckedBlocks; + if (!lval(S, Ctx->getASTContext(), Ptr, SourceType, Info, ConstexprKind, + CheckedBlocks)) { + return false; + } + + return true; +} + +bool EvaluationResult::checkMemberPointer(InterpState &S, + const MemberPointer &MemberPtr, + SourceInfo Info, + ConstantExprKind ConstexprKind) { + const CXXMethodDecl *MD = MemberPtr.getMemberFunction(); + if (!MD) + return true; + + if (MD->isImmediateFunction()) { + S.FFDiag(Info, diag::note_consteval_address_accessible) << false; + S.Note(MD->getLocation(), diag::note_declared_at); + return false; + } + + if (isForManglingOnly(ConstexprKind) || MD->isVirtual() || + !MD->hasAttr<DLLImportAttr>()) { + return true; + } + return false; +} + +bool EvaluationResult::checkFunctionPointer(InterpState &S, const Pointer &Ptr, + SourceInfo Info, + ConstantExprKind ConstexprKind) { + return checkFunctionPtr(S, Ptr, getStorageType(), Info, ConstexprKind); +} + } // namespace interp } // namespace clang diff --git a/clang/lib/AST/ByteCode/EvaluationResult.h b/clang/lib/AST/ByteCode/EvaluationResult.h index c296cc98ca375..4c4dd7172da9a 100644 --- a/clang/lib/AST/ByteCode/EvaluationResult.h +++ b/clang/lib/AST/ByteCode/EvaluationResult.h @@ -17,6 +17,7 @@ namespace clang { namespace interp { class EvalEmitter; class Context; +class MemberPointer; class Pointer; class SourceInfo; class InterpState; @@ -39,9 +40,7 @@ class EvaluationResult final { using DeclTy = llvm::PointerUnion<const Decl *, const Expr *>; private: -#ifndef NDEBUG - const Context *Ctx = nullptr; -#endif + const Context *Ctx; APValue Value; ResultKind Kind = Empty; DeclTy Source = nullptr; @@ -63,30 +62,29 @@ class EvaluationResult final { } public: -#ifndef NDEBUG EvaluationResult(const Context *Ctx) : Ctx(Ctx) {} -#else - EvaluationResult(const Context *Ctx) {} -#endif bool empty() const { return Kind == Empty; } bool isInvalid() const { return Kind == Invalid; } - - /// Returns an APValue for the evaluation result. - APValue toAPValue() const { - assert(!empty()); - assert(!isInvalid()); - return Value; - } - APValue stealAPValue() { return std::move(Value); } /// Check that all subobjects of the given pointer have been initialized. bool checkFullyInitialized(InterpState &S, const Pointer &Ptr) const; /// Check that none of the blocks the given pointer (transitively) points /// to are dynamically allocated. - bool checkReturnValue(InterpState &S, const Context &Ctx, const Pointer &Ptr, - const SourceInfo &Info); + bool checkDynamicAllocations(InterpState &S, const Context &Ctx, + const Pointer &Ptr, SourceInfo Info); + + bool checkLValue(InterpState &S, const Pointer &Ptr, SourceInfo Info, + ConstantExprKind ConstexprKind); + bool checkLValueFields(InterpState &S, const Pointer &Ptr, SourceInfo Info, + ConstantExprKind ConstexprKind); + + /// Check if the given member pointer can be returned from an evaluation. + bool checkMemberPointer(InterpState &S, const MemberPointer &MemberPtr, + SourceInfo Info, ConstantExprKind ConstexprKind); + bool checkFunctionPointer(InterpState &S, const Pointer &Ptr, SourceInfo Info, + ConstantExprKind ConstexprKind); QualType getSourceType() const { if (const auto *D = @@ -96,6 +94,7 @@ class EvaluationResult final { return E->getType(); return QualType(); } + QualType getStorageType() const; /// Dump to stderr. void dump() const; diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp index ebc7220aa5671..d926fa9b15128 100644 --- a/clang/lib/AST/ByteCode/Interp.cpp +++ b/clang/lib/AST/ByteCode/Interp.cpp @@ -890,6 +890,8 @@ bool CheckFinalLoad(InterpState &S, CodePtr OpPC, const Pointer &Ptr) { return false; if (!CheckMutable(S, OpPC, Ptr)) return false; + if (!S.inConstantContext() && isConstexprUnknown(Ptr)) + return false; return true; } diff --git a/clang/lib/AST/ByteCode/InterpState.cpp b/clang/lib/AST/ByteCode/InterpState.cpp index fd69559af5917..dd62e8da195db 100644 --- a/clang/lib/AST/ByteCode/InterpState.cpp +++ b/clang/lib/AST/ByteCode/InterpState.cpp @@ -30,18 +30,31 @@ InterpState::InterpState(const State &Parent, Program &P, InterpStack &Stk, EvalMode = Parent.EvalMode; } -InterpState::InterpState(const State &Parent, Program &P, InterpStack &Stk, - Context &Ctx, const Function *Func) - : State(Ctx.getASTContext(), Parent.getEvalStatus()), M(nullptr), P(P), +InterpState::InterpState(const EvalSettings &Settings, Program &P, + InterpStack &Stk, Context &Ctx, SourceMapper *M) + : State(Ctx.getASTContext(), Settings.EvalStatus), M(M), P(P), Stk(Stk), + Ctx(Ctx), BottomFrame(*this), Current(&BottomFrame), + StepsLeft(Ctx.getLangOpts().ConstexprStepLimit), + InfiniteSteps(StepsLeft == 0), EvalID(Ctx.getEvalID()) { + InConstantContext = Settings.InConstantContext; + CheckingPotentialConstantExpression = + Settings.CheckingPotentialConstantExpression; + CheckingForUndefinedBehavior = Settings.CheckingForUndefinedBehavior; + EvalMode = Settings.EvalMode; +} + +InterpState::InterpState(const EvalSettings &Settings, Program &P, + InterpStack &Stk, Context &Ctx, const Function *Func) + : State(Ctx.getASTContext(), Settings.EvalStatus), M(nullptr), P(P), Stk(Stk), Ctx(Ctx), BottomFrame(*this, Func, nullptr, CodePtr(), Func->getArgSize()), Current(&BottomFrame), StepsLeft(Ctx.getLangOpts().ConstexprStepLimit), InfiniteSteps(StepsLeft == 0), EvalID(Ctx.getEvalID()) { - InConstantContext = Parent.InConstantContext; + InConstantContext = Settings.InConstantContext; CheckingPotentialConstantExpression = - Parent.CheckingPotentialConstantExpression; - CheckingForUndefinedBehavior = Parent.CheckingForUndefinedBehavior; - EvalMode = Parent.EvalMode; + Settings.CheckingPotentialConstantExpression; + CheckingForUndefinedBehavior = Settings.CheckingForUndefinedBehavior; + EvalMode = Settings.EvalMode; } bool InterpState::inConstantContext() const { diff --git a/clang/lib/AST/ByteCode/InterpState.h b/clang/lib/AST/ByteCode/InterpState.h index 8ed92432f1c7e..e5772da463f02 100644 --- a/clang/lib/AST/ByteCode/InterpState.h +++ b/clang/lib/AST/ByteCode/InterpState.h @@ -15,6 +15,7 @@ #include "Context.h" #include "DynamicAllocator.h" +#include "EvalSettings.h" #include "Floating.h" #include "Function.h" #include "InterpFrame.h" @@ -35,10 +36,14 @@ struct StdAllocatorCaller { /// Interpreter context. class InterpState final : public State, public SourceMapper { public: + // FIXME: Get rid of this constructor as well. InterpState(const State &Parent, Program &P, InterpStack &Stk, Context &Ctx, SourceMapper *M = nullptr); - InterpState(const State &Parent, Program &P, InterpStack &Stk, Context &Ctx, - const Function *Func); + + InterpState(const EvalSettings &Settings, Program &P, InterpStack &Stk, + Context &Ctx, SourceMapper *M = nullptr); + InterpState(const EvalSettings &Settings, Program &P, InterpStack &Stk, + Context &Ctx, const Function *Func); ~InterpState(); diff --git a/clang/lib/AST/ExprConstShared.h b/clang/lib/AST/ExprConstShared.h index 619c79a1408f3..5035306a8249c 100644 --- a/clang/lib/AST/ExprConstShared.h +++ b/clang/lib/AST/ExprConstShared.h @@ -14,6 +14,7 @@ #ifndef LLVM_CLANG_LIB_AST_EXPRCONSTSHARED_H #define LLVM_CLANG_LIB_AST_EXPRCONSTSHARED_H +#include "ByteCode/State.h" #include "clang/Basic/TypeTraits.h" #include <cstdint> #include <optional> @@ -89,4 +90,46 @@ std::optional<llvm::APFloat> EvalScalarMinMaxFp(const llvm::APFloat &A, const llvm::APFloat &B, std::optional<llvm::APSInt> RoundingMode, bool IsMin); +/// Determines whether the given kind of constant expression is only ever +/// used for name mangling. If so, it's permitted to reference things that we +/// can't generate code for (in particular, dllimported functions). +inline bool isForManglingOnly(ConstantExprKind Kind) { + switch (Kind) { + case ConstantExprKind::Normal: + case ConstantExprKind::ClassTemplateArgument: + case ConstantExprKind::ImmediateInvocation: + // Note that non-type template arguments of class type are emitted as + // template parameter objects. + return false; + + case ConstantExprKind::NonClassTemplateArgument: + return true; + } + llvm_unreachable("unknown ConstantExprKind"); +} + +inline bool isTemplateArgument(ConstantExprKind Kind) { + switch (Kind) { + case ConstantExprKind::Normal: + case ConstantExprKind::ImmediateInvocation: + return false; + + case ConstantExprKind::ClassTemplateArgument: + case ConstantExprKind::NonClassTemplateArgument: + return true; + } + llvm_unreachable("unknown ConstantExprKind"); +} + +/// Should this call expression be treated as forming an opaque constant? +inline bool isOpaqueConstantCall(const CallExpr *E) { + unsigned Builtin = E->getBuiltinCallee(); + return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString || + Builtin == Builtin::BI__builtin___NSStringMakeConstantString || + Builtin == Builtin::BI__builtin_ptrauth_sign_constant || + Builtin == Builtin::BI__builtin_function_start); +} + +bool isGlobalLValue(const ValueDecl *D, const Expr *E); + #endif diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp index c7805f7a2dbcd..dc8b5c7a1b8c2 100644 --- a/clang/lib/AST/ExprConstant.cpp +++ b/clang/lib/AST/ExprConstant.cpp @@ -33,6 +33,7 @@ //===----------------------------------------------------------------------===// #include "ByteCode/Context.h" +#include "ByteCode/EvalSettings.h" #include "ByteCode/Frame.h" #include "ByteCode/State.h" #include "ExprConstShared.h" @@ -145,37 +146,6 @@ namespace { return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E); } - /// Determines whether the given kind of constant expression is only ever - /// used for name mangling. If so, it's permitted to reference things that we - /// can't generate code for (in particular, dllimported functions). - static bool isForManglingOnly(ConstantExprKind Kind) { - switch (Kind) { - case ConstantExprKind::Normal: - case ConstantExprKind::ClassTemplateArgument: - case ConstantExprKind::ImmediateInvocation: - // Note that non-type template arguments of class type are emitted as - // template parameter objects. - return false; - - case ConstantExprKind::NonClassTemplateArgument: - return true; - } - llvm_unreachable("unknown ConstantExprKind"); - } - - static bool isTemplateArgument(ConstantExprKind Kind) { - switch (Kind) { - case ConstantExprKind::Normal: - case ConstantExprKind::ImmediateInvocation: - return false; - - case ConstantExprKind::ClassTemplateArgument: - case ConstantExprKind::NonClassTemplateArgument: - return true; - } - llvm_unreachable("unknown ConstantExprKind"); - } - /// The bound to claim that an array of unknown bound has. /// The value in MostDerivedArraySize is undefined in this case. So, set it /// to an arbitrary value that's likely to loudly break things if it's used. @@ -1925,31 +1895,30 @@ static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) { return true; } -/// Should this call expression be treated as forming an opaque constant? -static bool IsOpaqueConstantCall(const CallExpr *E) { - unsigned Builtin = E->getBuiltinCallee(); - return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString || - Builtin == Builtin::BI__builtin___NSStringMakeConstantString || - Builtin == Builtin::BI__builtin_ptrauth_sign_constant || - Builtin == Builtin::BI__builtin_function_start); -} - static bool IsOpaqueConstantCall(const LValue &LVal) { const auto *BaseExpr = llvm::dyn_cast_if_present<CallExpr>(LVal.Base.dyn_cast<const Expr *>()); - return BaseExpr && IsOpaqueConstantCall(BaseExpr); + return BaseExpr && isOpaqueConstantCall(BaseExpr); } static bool IsGlobalLValue(APValue::LValueBase B) { + if (B.is<TypeInfoLValue>() || B.is<DynamicAllocLValue>()) + return true; + + return isGlobalLValue(B.dyn_cast<const ValueDecl *>(), + B.dyn_cast<const Expr *>()); +} + +bool isGlobalLValue(const ValueDecl *D, const Expr *E) { // C++11 [expr.const]p3 An address constant expression is a prvalue core // constant expression of pointer type that evaluates to... // ... a null pointer value, or a prvalue core constant expression of type // std::nullptr_t. - if (!B) + if (!D && !E) return true; - if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { + if (D) { // ... the address of an object with static storage duration, if (const VarDecl *VD = dyn_cast<VarDecl>(D)) return VD->hasGlobalStorage(); @@ -1961,10 +1930,7 @@ static bool IsGlobalLValue(APValue::LValueBase B) { return isa<FunctionDecl, MSGuidDecl, UnnamedGlobalConstantDecl>(D); } - if (B.is<TypeInfoLValue>() || B.is<DynamicAllocLValue>()) - return true; - - const Expr *E = B.get<const Expr*>(); + assert(E); switch (E->getStmtClass()) { default: return false; @@ -1985,7 +1951,7 @@ static bool IsGlobalLValue(APValue::LValueBase B) { case Expr::ObjCBoxedExprClass: return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer(); case Expr::CallExprClass: - return IsOpaqueConstantCall(cast<CallExpr>(E)); + return isOpaqueConstantCall(cast<CallExpr>(E)); // For GCC compatibility, &&label has static storage duration. case Expr::AddrLabelExprClass: return true; @@ -2006,6 +1972,8 @@ static bool IsGlobalLValue(APValue::LValueBase B) { // an expression might be a global lvalue. return true; } + + return false; } static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) { @@ -10294,7 +10262,7 @@ static bool isOneByteCharacterType(QualType T) { bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp) { - if (IsOpaqueConstantCall(E)) + if (isOpaqueConstantCall(E)) return Success(E); switch (BuiltinOp) { @@ -20545,12 +20513,8 @@ static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) { if (!CheckLiteralType(Info, E)) return false; - if (Info.EnableNewConstInterp) { - if (!Info.Ctx.getInterpContext().evaluateAsRValue(Info, E, Result)) - return false; - return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result, - ConstantExprKind::Normal); - } + if (Info.EnableNewConstInterp) + return Info.Ctx.getInterpContext().evaluateAsRValue(Info, E, Result); if (!::Evaluate(Result, Info, E)) return false; @@ -20682,6 +20646,18 @@ bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx, assert(!isValueDependent() && "Expression evaluator can't be called on a dependent expression."); ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsRValue"); + + bool IsConst; + if (FastEvaluateAsRValue(this, Result.Val, Ctx, IsConst) && + Result.Val.hasValue()) + return true; + + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::IgnoreSideEffects, Result); + S.InConstantContext = InConstantContext; + return Ctx.getInterpContext().evaluateAsRValue(S, this, Result.Val); + } + EvalInfo Info(Ctx, Result, EvaluationMode::IgnoreSideEffects); Info.InConstantContext = InConstantContext; return ::EvaluateAsRValue(this, Result, Ctx, Info); @@ -20745,22 +20721,18 @@ bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx, "Expression evaluator can't be called on a dependent expression."); ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsLValue"); + + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantFold, Result); + S.InConstantContext = InConstantContext; + return Ctx.getInterpContext().evaluate(S, this, Result.Val); + } + EvalInfo Info(Ctx, Result, EvaluationMode::ConstantFold); Info.InConstantContext = InConstantContext; LValue LV; CheckedTemporaries CheckedTemps; - if (Info.EnableNewConstInterp) { - if (!Info.Ctx.getInterpContext().evaluate(Info, this, Result.Val, - ConstantExprKind::Normal)) - return false; - - LV.setFrom(Ctx, Result.Val); - return CheckLValueConstantExpression( - Info, getExprLoc(), Ctx.getLValueReferenceType(getType()), LV, - ConstantExprKind::Normal, CheckedTemps); - } - if (!EvaluateLValue(this, LV, Info) || !Info.discardCleanups() || Result.HasSideEffects || !CheckLValueConstantExpression(Info, getExprLoc(), @@ -20806,17 +20778,16 @@ bool Expr::EvaluateAsConstantExpr(EvalResult &Result, const ASTContext &Ctx, return true; ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsConstantExpr"); - EvaluationMode EM = EvaluationMode::ConstantExpression; - EvalInfo Info(Ctx, Result, EM); - Info.InConstantContext = true; - if (Info.EnableNewConstInterp) { - if (!Info.Ctx.getInterpContext().evaluate(Info, this, Result.Val, Kind)) - return false; - return CheckConstantExpression(Info, getExprLoc(), - getStorageType(Ctx, this), Result.Val, Kind); + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantExpression, Result, Kind); + S.InConstantContext = true; + return Ctx.getInterpContext().evaluate(S, this, Result.Val); } + EvalInfo Info(Ctx, Result, EvaluationMode::ConstantExpression); + Info.InConstantContext = true; + // The type of the object we're initializing is 'const T' for a class NTTP. QualType T = getType(); if (Kind == ConstantExprKind::ClassTemplateArgument) @@ -20881,52 +20852,50 @@ bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx, Expr::EvalStatus EStatus; EStatus.Diag = &Notes; - EvalInfo Info(Ctx, EStatus, - (IsConstantInitialization && - (Ctx.getLangOpts().CPlusPlus || Ctx.getLangOpts().C23)) - ? EvaluationMode::ConstantExpression - : EvaluationMode::ConstantFold); - Info.setEvaluatingDecl(VD, Value); - Info.InConstantContext = IsConstantInitialization; + EvaluationMode EvalMode = + (IsConstantInitialization && + (Ctx.getLangOpts().CPlusPlus || Ctx.getLangOpts().C23)) + ? EvaluationMode::ConstantExpression + : EvaluationMode::ConstantFold; + + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvalMode, EStatus); + S.InConstantContext = IsConstantInitialization; + return Ctx.getInterpContext().evaluateAsInitializer(S, VD, this, Value); + } SourceLocation DeclLoc = VD->getLocation(); QualType DeclTy = VD->getType(); - if (Info.EnableNewConstInterp) { - auto &InterpCtx = Ctx.getInterpContext(); - if (!InterpCtx.evaluateAsInitializer(Info, VD, this, Value)) - return false; - - return CheckConstantExpression(Info, DeclLoc, DeclTy, Value, - ConstantExprKind::Normal); - } else { - LValue LVal; - LVal.set(VD); - - { - // C++23 [intro.execution]/p5 - // A full-expression is ... an init-declarator ([dcl.decl]) or a - // mem-initializer. - // So we need to make sure temporary objects are destroyed after having - // evaluated the expression (per C++23 [class.temporary]/p4). - // - // FIXME: Otherwise this may break test/Modules/pr68702.cpp because the - // serialization code calls ParmVarDecl::getDefaultArg() which strips the - // outermost FullExpr, such as ExprWithCleanups. - FullExpressionRAII Scope(Info); - if (!EvaluateInPlace(Value, Info, LVal, this, - /*AllowNonLiteralTypes=*/true) || - EStatus.HasSideEffects) - return false; - } + EvalInfo Info(Ctx, EStatus, EvalMode); + Info.setEvaluatingDecl(VD, Value); + Info.InConstantContext = IsConstantInitialization; - // At this point, any lifetime-extended temporaries are completely - // initialized. - Info.performLifetimeExtension(); + LValue LVal; + LVal.set(VD); - if (!Info.discardCleanups()) - llvm_unreachable("Unhandled cleanup; missing full expression marker?"); + { + // C++23 [intro.execution]/p5 + // A full-expression is ... an init-declarator ([dcl.decl]) or a + // mem-initializer. + // So we need to make sure temporary objects are destroyed after having + // evaluated the expression (per C++23 [class.temporary]/p4). + // + // FIXME: Otherwise this may break test/Modules/pr68702.cpp because the + // serialization code calls ParmVarDecl::getDefaultArg() which strips the + // outermost FullExpr, such as ExprWithCleanups. + FullExpressionRAII Scope(Info); + if (!EvaluateInPlace(Value, Info, LVal, this, + /*AllowNonLiteralTypes=*/true) || + EStatus.HasSideEffects) + return false; } + // At this point, any lifetime-extended temporaries are completely + // initialized. + Info.performLifetimeExtension(); + + if (!Info.discardCleanups()) + llvm_unreachable("Unhandled cleanup; missing full expression marker?"); return CheckConstantExpression(Info, DeclLoc, DeclTy, Value, ConstantExprKind::Normal) && @@ -21694,20 +21663,23 @@ bool Expr::isPotentialConstantExpr(const FunctionDecl *FD, return Name; }); + const ASTContext &Ctx = FD->getASTContext(); Expr::EvalStatus Status; Status.Diag = &Diags; - EvalInfo Info(FD->getASTContext(), Status, - EvaluationMode::ConstantExpression); - Info.InConstantContext = true; - Info.CheckingPotentialConstantExpression = true; - // The constexpr VM attempts to compile all methods to bytecode here. - if (Info.EnableNewConstInterp) { - Info.Ctx.getInterpContext().isPotentialConstantExpr(Info, FD); + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantExpression, Status); + S.InConstantContext = true; + S.CheckingPotentialConstantExpression = true; + FD->getASTContext().getInterpContext().isPotentialConstantExpr(S, FD); return Diags.empty(); } + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantExpression); + Info.InConstantContext = true; + Info.CheckingPotentialConstantExpression = true; + const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr; @@ -21743,20 +21715,24 @@ bool Expr::isPotentialConstantExprUnevaluated(Expr *E, PartialDiagnosticAt> &Diags) { assert(!E->isValueDependent() && "Expression evaluator can't be called on a dependent expression."); - + const ASTContext &Ctx = FD->getASTContext(); Expr::EvalStatus Status; Status.Diag = &Diags; - EvalInfo Info(FD->getASTContext(), Status, - EvaluationMode::ConstantExpressionUnevaluated); - Info.InConstantContext = true; - Info.CheckingPotentialConstantExpression = true; - - if (Info.EnableNewConstInterp) { - Info.Ctx.getInterpContext().isPotentialConstantExprUnevaluated(Info, E, FD); + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantExpressionUnevaluated, + Status); + S.InConstantContext = true; + S.CheckingPotentialConstantExpression = true; + FD->getASTContext().getInterpContext().isPotentialConstantExprUnevaluated( + S, E, FD); return Diags.empty(); } + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantExpressionUnevaluated); + Info.InConstantContext = true; + Info.CheckingPotentialConstantExpression = true; + // Fabricate a call stack frame to give the arguments a plausible cover story. CallStackFrame Frame(Info, SourceLocation(), FD, /*This=*/nullptr, /*CallExpr=*/nullptr, CallRef()); @@ -21772,9 +21748,12 @@ std::optional<uint64_t> Expr::tryEvaluateObjectSize(const ASTContext &Ctx, return std::nullopt; Expr::EvalStatus Status; + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantFold, Status); + return Ctx.getInterpContext().tryEvaluateObjectSize(S, this, Type); + } + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantFold); - if (Info.EnableNewConstInterp) - return Info.Ctx.getInterpContext().tryEvaluateObjectSize(Info, this, Type); return tryEvaluateBuiltinObjectSize(this, Type, Info); } @@ -21831,15 +21810,16 @@ EvaluateBuiltinStrLen(const Expr *E, EvalInfo &Info, std::optional<std::string> Expr::tryEvaluateString(ASTContext &Ctx) const { Expr::EvalStatus Status; - EvalInfo Info(Ctx, Status, EvaluationMode::ConstantFold); std::string StringResult; - if (Info.EnableNewConstInterp) { - if (!Info.Ctx.getInterpContext().evaluateString(Info, this, StringResult)) + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantFold, Status); + if (!Ctx.getInterpContext().evaluateString(S, this, StringResult)) return std::nullopt; return StringResult; } + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantFold); if (EvaluateBuiltinStrLen(this, Info, &StringResult)) return StringResult; return std::nullopt; @@ -21851,13 +21831,15 @@ static bool EvaluateCharRangeAsStringImpl(const Expr *, T &Result, const Expr *PtrExpression, ASTContext &Ctx, Expr::EvalResult &Status) { + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantExpression, Status); + S.InConstantContext = true; + return Ctx.getInterpContext().evaluateCharRange(S, SizeExpression, + PtrExpression, Result); + } + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantExpression); Info.InConstantContext = true; - - if (Info.EnableNewConstInterp) - return Info.Ctx.getInterpContext().evaluateCharRange(Info, SizeExpression, - PtrExpression, Result); - LValue String; FullExpressionRAII Scope(Info); APSInt SizeValue; @@ -21919,10 +21901,13 @@ bool Expr::EvaluateCharRangeAsString(APValue &Result, std::optional<uint64_t> Expr::tryEvaluateStrLen(const ASTContext &Ctx) const { Expr::EvalStatus Status; - EvalInfo Info(Ctx, Status, EvaluationMode::ConstantFold); - if (Info.EnableNewConstInterp) - return Info.Ctx.getInterpContext().evaluateStrlen(Info, this); + if (Ctx.getLangOpts().EnableNewConstInterp) { + interp::EvalSettings S(EvaluationMode::ConstantFold, Status); + return Ctx.getInterpContext().evaluateStrlen(S, this); + } + + EvalInfo Info(Ctx, Status, EvaluationMode::ConstantFold); return EvaluateBuiltinStrLen(this, Info); } diff --git a/clang/test/AST/ByteCode/codegen-constexpr-unknown.cpp b/clang/test/AST/ByteCode/codegen-constexpr-unknown.cpp index d5312c09d0bd8..20a1f805c0d4b 100644 --- a/clang/test/AST/ByteCode/codegen-constexpr-unknown.cpp +++ b/clang/test/AST/ByteCode/codegen-constexpr-unknown.cpp @@ -1,5 +1,5 @@ -// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm -fcxx-exceptions -o - %s | FileCheck %s --check-prefix=CHECK -// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm -fcxx-exceptions -o - %s -fexperimental-new-constant-interpreter -DINTERP | FileCheck %s --check-prefix=CHECK,INTERP +// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm -fcxx-exceptions -o - %s | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm -fcxx-exceptions -o - %s -fexperimental-new-constant-interpreter -DINTERP | FileCheck %s /// CodeGenFunction::ConstantFoldsToSimpleInteger() for the if condition /// needs to succeed and return true. @@ -7,8 +7,6 @@ /// variable to the topmost scope, otherwise we will pick the call scope /// of to_address and de-allocate the local variable at the end of the /// to_address call. -/// FIXME: This is not currently correct since we still mark p as -/// constexpr-unknown and then reject it when comparing. extern void abort2(); constexpr const int* to_address(const int *a) { return a; @@ -23,7 +21,7 @@ void rightscope() { // CHECK-NEXT: entry: // CHECK-NEXT: %p = alloca i32 // CHECK-NEXT: store i32 0, ptr %p -// INTERP-NEXT: call noundef ptr @_Z10to_addressPKi(ptr noundef %p) +// CHECK-NEXT: ret void /// In the if expression below, the read from s.i should fail. diff --git a/clang/test/AST/ByteCode/unused-variables.cpp b/clang/test/AST/ByteCode/unused-variables.cpp new file mode 100644 index 0000000000000..c675f31161aaa --- /dev/null +++ b/clang/test/AST/ByteCode/unused-variables.cpp @@ -0,0 +1,87 @@ +// RUN: %clang_cc1 -std=c++23 -Wunused -fexperimental-new-constant-interpreter -verify=both,expected %s +// RUN: %clang_cc1 -std=c++23 -Wunused -verify=both,ref %s + + +// both-no-diagnostics +namespace BaseUninitializedField { + struct __optional_storage_base { + int value; + template <class _UArg> constexpr __optional_storage_base(_UArg) {} + }; + + struct optional : __optional_storage_base { + template <class _Up> + constexpr optional(_Up &&) : __optional_storage_base(0) {} + }; + int main_x; + void test() { optional opt{main_x}; } +} + + +namespace BaseInvalidLValue { + int *addressof(int &); + struct in_place_t { + } in_place; + template <class> struct __optional_storage_base { + int *__value_; + template <class _UArg> + constexpr __optional_storage_base(in_place_t, _UArg &&__uarg) { + int &__trans_tmp_1(__uarg); + int &__val = __trans_tmp_1; + int &__r(__val); + __value_ = addressof(__r); + } + }; + template <class _Tp> + struct __optional_copy_base : __optional_storage_base<_Tp> { + using __optional_storage_base<_Tp>::__optional_storage_base; + }; + template <class _Tp> struct __optional_move_base : __optional_copy_base<_Tp> { + using __optional_copy_base<_Tp>::__optional_copy_base; + }; + template <class _Tp> + struct __optional_copy_assign_base : __optional_move_base<_Tp> { + using __optional_move_base<_Tp>::__optional_move_base; + }; + template <class _Tp> + struct __optional_move_assign_base : __optional_copy_assign_base<_Tp> { + using __optional_copy_assign_base<_Tp>::__optional_copy_assign_base; + }; + struct optional : __optional_move_assign_base<int> { + template <class _Up> + constexpr optional(_Up &&__v) : __optional_move_assign_base(in_place, __v) {} + }; + int test() { + int x; + /// With -Wunused, we will call EvaluateAsInitializer() on the variable here and if that + /// succeeds, it will be reported unused. It should NOT succeed because the __value_ is an + /// invalid lvalue. + optional opt{x}; + return 0; + } +} + +namespace NonConstantInitChecksLValue { + template <class _Tp, class> + concept __weakly_equality_comparable_with = requires(_Tp __t) { __t; }; + template <class _Ip> + concept input_or_output_iterator = requires(_Ip __i) { __i; }; + template <class _Sp, class _Ip> + concept sentinel_for = __weakly_equality_comparable_with<_Sp, _Ip>; + + template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent = _Iter> + struct subrange { + _Iter __begin_; + _Sent __end_; + constexpr subrange(auto, _Sent __sent) : __begin_(), __end_(__sent) {} + }; + struct forward_iterator { + int *it_; + }; + void test() { + using Range = subrange<forward_iterator>; + int buffer[]{}; + /// The EvaluateAsInitializer() call needs to check the LValue and not just the lvalue fields. + Range input(forward_iterator{}, {buffer}); + } +} diff --git a/clang/test/CodeGenCXX/global-init.cpp b/clang/test/CodeGenCXX/global-init.cpp index 52039a5208223..f10f1be4ce95d 100644 --- a/clang/test/CodeGenCXX/global-init.cpp +++ b/clang/test/CodeGenCXX/global-init.cpp @@ -6,6 +6,14 @@ // RUN: | FileCheck -check-prefix CHECK-NOBUILTIN %s // RUN: %clang_cc1 %std_cxx17- -triple=x86_64-apple-darwin10 -emit-llvm -fexceptions %s -o - | FileCheck %s +// RUN: %clang_cc1 %std_cxx98-14 -triple=x86_64-apple-darwin10 -emit-llvm -fexceptions %s -o - -fexperimental-new-constant-interpreter | FileCheck %s --check-prefixes=CHECK,PRE17 +// RUN: %clang_cc1 %std_cxx98-14 -triple=x86_64-apple-darwin10 -emit-llvm %s -o - -fexperimental-new-constant-interpreter | FileCheck %s --check-prefixes=CHECK-NOEXC,PRE17 +// RUN: %clang_cc1 %std_cxx98-14 -triple=x86_64-apple-darwin10 -emit-llvm -mframe-pointer=non-leaf %s -o - -fexperimental-new-constant-interpreter \ +// RUN: | FileCheck -check-prefix CHECK-FP %s +// RUN: %clang_cc1 %std_cxx98-14 -triple=x86_64-apple-darwin10 -emit-llvm %s -o - -fno-builtin -fexperimental-new-constant-interpreter \ +// RUN: | FileCheck -check-prefix CHECK-NOBUILTIN %s +// RUN: %clang_cc1 %std_cxx17- -triple=x86_64-apple-darwin10 -emit-llvm -fexceptions %s -o - -fexperimental-new-constant-interpreter | FileCheck %s + struct A { A(); ~A(); diff --git a/clang/test/SemaCXX/PR19955.cpp b/clang/test/SemaCXX/PR19955.cpp index cbbe2fe9af164..6fa22ab846374 100644 --- a/clang/test/SemaCXX/PR19955.cpp +++ b/clang/test/SemaCXX/PR19955.cpp @@ -1,5 +1,8 @@ // RUN: %clang_cc1 -triple i686-win32 -verify -std=c++11 %s // RUN: %clang_cc1 -triple i686-mingw32 -verify -std=c++11 %s +// RUN: %clang_cc1 -triple i686-win32 -verify -std=c++11 %s -fexperimental-new-constant-interpreter +// RUN: %clang_cc1 -triple i686-mingw32 -verify -std=c++11 %s -fexperimental-new-constant-interpreter + extern int __attribute__((dllimport)) var; constexpr int *varp = &var; // expected-error {{must be initialized by a constant expression}} >From 742a680516bc5fbc14a38fc460b2a68d811d7b6b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <[email protected]> Date: Fri, 27 Feb 2026 11:16:31 +0100 Subject: [PATCH 2/3] const ASTContext --- clang/lib/AST/ByteCode/EvaluationResult.cpp | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/clang/lib/AST/ByteCode/EvaluationResult.cpp b/clang/lib/AST/ByteCode/EvaluationResult.cpp index ddc3470ae86bd..7d1f7a3f0d553 100644 --- a/clang/lib/AST/ByteCode/EvaluationResult.cpp +++ b/clang/lib/AST/ByteCode/EvaluationResult.cpp @@ -301,11 +301,11 @@ static bool checkFunctionPtr(InterpState &S, const Pointer &Ptr, return true; } -static bool lvalFields(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, - QualType PtrType, SourceInfo Info, +static bool lvalFields(InterpState &S, const ASTContext &Ctx, + const Pointer &Ptr, QualType PtrType, SourceInfo Info, ConstantExprKind ConstexprKind, llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks); -static bool lval(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, +static bool lval(InterpState &S, const ASTContext &Ctx, const Pointer &Ptr, QualType PtrType, SourceInfo Info, ConstantExprKind ConstexprKind, llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks) { @@ -407,8 +407,8 @@ static bool lval(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, return true; } -static bool lvalFields(InterpState &S, ASTContext &Ctx, const Pointer &Ptr, - QualType PtrType, SourceInfo Info, +static bool lvalFields(InterpState &S, const ASTContext &Ctx, + const Pointer &Ptr, QualType PtrType, SourceInfo Info, ConstantExprKind ConstexprKind, llvm::SmallPtrSet<const Block *, 4> &CheckedBlocks) { if (!Ptr.isBlockPointer()) >From b9e288ddec4ae571feba99490bf83a22fcd52e09 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <[email protected]> Date: Fri, 27 Feb 2026 11:03:55 +0100 Subject: [PATCH 3/3] hasptrfield --- clang/lib/AST/ByteCode/EvaluationResult.cpp | 5 +++++ clang/lib/AST/ByteCode/Program.cpp | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/clang/lib/AST/ByteCode/EvaluationResult.cpp b/clang/lib/AST/ByteCode/EvaluationResult.cpp index 7d1f7a3f0d553..6c761e08ed98f 100644 --- a/clang/lib/AST/ByteCode/EvaluationResult.cpp +++ b/clang/lib/AST/ByteCode/EvaluationResult.cpp @@ -416,6 +416,8 @@ static bool lvalFields(InterpState &S, const ASTContext &Ctx, const Descriptor *FieldDesc = Ptr.getFieldDesc(); if (const Record *R = Ptr.getRecord()) { + if (!R->hasPtrField()) + return true; for (const Record::Field &F : R->fields()) { if (F.Desc->isPrimitive() && F.Desc->getPrimType() == PT_Ptr) { QualType FieldType = F.Decl->getType(); @@ -467,6 +469,9 @@ static bool lvalFields(InterpState &S, const ASTContext &Ctx, return true; } if (FieldDesc->isCompositeArray()) { + if (FieldDesc->ElemRecord && !FieldDesc->ElemRecord->hasPtrField()) + return true; + for (unsigned I = 0; I != FieldDesc->getNumElems(); ++I) { Pointer Elem = Ptr.atIndex(I).narrow(); if (!lvalFields(S, Ctx, Elem, FieldDesc->getElemQualType(), Info, diff --git a/clang/lib/AST/ByteCode/Program.cpp b/clang/lib/AST/ByteCode/Program.cpp index 7eebb303d8553..980e1e87f5ab8 100644 --- a/clang/lib/AST/ByteCode/Program.cpp +++ b/clang/lib/AST/ByteCode/Program.cpp @@ -380,7 +380,7 @@ Record *Program::getOrCreateRecord(const RecordDecl *RD) { Desc = createDescriptor(FD, FT.getTypePtr(), std::nullopt, IsConst, /*isTemporary=*/false, IsMutable, IsVolatile); HasPtrField = HasPtrField || (Desc && Desc->isPrimitiveArray() && - Desc->getPrimType() == PT_Ptr); + Desc->getPrimType() == PT_Ptr) || (Desc && Desc->ElemRecord && Desc->ElemRecord->hasPtrField()); } if (!Desc) return nullptr; _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
