[clang] Enable AST mutation in the constant evaluator (PR #115168)
Vlad Serebrennikov via cfe-commits
cfe-commits at lists.llvm.org
Mon Nov 25 10:48:04 PST 2024
https://github.com/Endilll updated https://github.com/llvm/llvm-project/pull/115168
>From 5ca48e03412b1b8e9253f13356b9cc957f6fd9e5 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Wed, 6 Nov 2024 17:58:43 +0300
Subject: [PATCH 01/13] Add EvalASTMutator interface with
`InstantiateFunctionDefinition` function
---
clang/include/clang/AST/ASTContext.h | 2 +-
clang/include/clang/AST/Decl.h | 22 ++++++++++---
clang/include/clang/AST/Expr.h | 3 +-
clang/include/clang/Sema/Sema.h | 17 ++++++++++
clang/lib/AST/ASTContext.cpp | 4 +--
clang/lib/AST/Decl.cpp | 16 +++++-----
clang/lib/AST/ExprConstant.cpp | 24 +++++++++++---
clang/lib/Sema/Sema.cpp | 11 ++++++-
clang/lib/Sema/SemaDecl.cpp | 5 +--
.../constexpr-function-instantiation.cpp | 31 +++++++++++++++++++
10 files changed, 113 insertions(+), 22 deletions(-)
create mode 100644 clang/test/SemaCXX/constexpr-function-instantiation.cpp
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index a4d36f2eacd5d1..d143591de9f2cd 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -3258,7 +3258,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
///
/// \returns true if the function/var must be CodeGen'ed/deserialized even if
/// it is not used.
- bool DeclMustBeEmitted(const Decl *D);
+ bool DeclMustBeEmitted(const Decl *D, EvalASTMutator *ASTMutator = nullptr);
/// Visits all versions of a multiversioned function with the passed
/// predicate.
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 7ff35d73df5997..89a2833c82194d 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -78,6 +78,18 @@ class UnresolvedSetImpl;
class VarTemplateDecl;
enum class ImplicitParamKind;
+/// Interface that allows constant evaluator to mutate AST.
+/// When constant evaluation is triggered by Sema, it can supply a proper
+/// implementation of this interface.
+struct EvalASTMutator {
+ virtual ~EvalASTMutator() = default;
+
+ virtual void
+ InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
+ FunctionDecl *Function, bool Recursive,
+ bool DefinitionRequired, bool AtEndOfTU) = 0;
+};
+
/// The top declaration context.
class TranslationUnitDecl : public Decl,
public DeclContext,
@@ -1355,11 +1367,12 @@ class VarDecl : public DeclaratorDecl, public Redeclarable<VarDecl> {
/// Attempt to evaluate the value of the initializer attached to this
/// declaration, and produce notes explaining why it cannot be evaluated.
/// Returns a pointer to the value if evaluation succeeded, 0 otherwise.
- APValue *evaluateValue() const;
+ APValue *evaluateValue(EvalASTMutator *ASTMutator = nullptr) const;
private:
APValue *evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization) const;
+ bool IsConstantInitialization,
+ EvalASTMutator *ASTMutator = nullptr) const;
public:
/// Return the already-evaluated value of this variable's
@@ -1391,8 +1404,9 @@ class VarDecl : public DeclaratorDecl, public Redeclarable<VarDecl> {
/// Evaluate the initializer of this variable to determine whether it's a
/// constant initializer. Should only be called once, after completing the
/// definition of the variable.
- bool checkForConstantInitialization(
- SmallVectorImpl<PartialDiagnosticAt> &Notes) const;
+ bool
+ checkForConstantInitialization(SmallVectorImpl<PartialDiagnosticAt> &Notes,
+ EvalASTMutator *ASTMutator = nullptr) const;
void setInitStyle(InitializationStyle Style) {
VarDeclBits.InitStyle = Style;
diff --git a/clang/include/clang/AST/Expr.h b/clang/include/clang/AST/Expr.h
index 466c65a9685ad3..ccf7fd226b5a8f 100644
--- a/clang/include/clang/AST/Expr.h
+++ b/clang/include/clang/AST/Expr.h
@@ -734,7 +734,8 @@ class Expr : public ValueStmt {
bool EvaluateAsInitializer(APValue &Result, const ASTContext &Ctx,
const VarDecl *VD,
SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitializer) const;
+ bool IsConstantInitializer,
+ EvalASTMutator *ASTMutator = nullptr) const;
/// EvaluateWithSubstitution - Evaluate an expression as if from the context
/// of a call to the given function with the given arguments, inside an
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 93d98e1cbb9c81..1c0c6949573335 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -153,6 +153,7 @@ enum class OverloadCandidateParamOrder : char;
enum OverloadCandidateRewriteKind : unsigned;
class OverloadCandidateSet;
class Preprocessor;
+class Sema;
class SemaAMDGPU;
class SemaARM;
class SemaAVR;
@@ -352,6 +353,15 @@ struct SkipBodyInfo {
NamedDecl *New = nullptr;
};
+/// Implementation of EvalASTMutator interface that enables constant evaluator
+/// to modify AST, e.g. to instantiate templates.
+struct SemaASTMutator : EvalASTMutator {
+ Sema &SemaRef;
+ SemaASTMutator(Sema &SemaRef) void InstantiateFunctionDefinition(
+ SourceLocation PointOfInstantiation, FunctionDecl *Function,
+ bool Recursive, bool DefinitionRequired, bool AtEndOfTU) override;
+};
+
/// Describes the result of template argument deduction.
///
/// The TemplateDeductionResult enumeration describes the result of
@@ -1042,6 +1052,9 @@ class Sema final : public SemaBase {
/// CurContext - This is the current declaration context of parsing.
DeclContext *CurContext;
+ /// Get a Sema implementation of EvalASTMutator interface.
+ SemaASTMutator *getASTMutator() { return &ASTMutator; }
+
SemaAMDGPU &AMDGPU() {
assert(AMDGPUPtr);
return *AMDGPUPtr;
@@ -1199,6 +1212,10 @@ class Sema final : public SemaBase {
mutable IdentifierInfo *Ident_super;
+ /// EvalASTMutator implementation that can be passed to constant evaluator
+ /// to enable it to do AST mutations, e.g. template instantiation.
+ SemaASTMutator ASTMutator;
+
std::unique_ptr<SemaAMDGPU> AMDGPUPtr;
std::unique_ptr<SemaARM> ARMPtr;
std::unique_ptr<SemaAVR> AVRPtr;
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 69892bda42b256..0aaf23af28d3d6 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -12522,7 +12522,7 @@ GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) const {
basicGVALinkageForVariable(*this, VD)));
}
-bool ASTContext::DeclMustBeEmitted(const Decl *D) {
+bool ASTContext::DeclMustBeEmitted(const Decl *D, EvalASTMutator *ASTMutator) {
if (const auto *VD = dyn_cast<VarDecl>(D)) {
if (!VD->isFileVarDecl())
return false;
@@ -12627,7 +12627,7 @@ bool ASTContext::DeclMustBeEmitted(const Decl *D) {
// Variables that have initialization with side-effects are required.
if (VD->getInit() && VD->getInit()->HasSideEffects(*this) &&
// We can get a value-dependent initializer during error recovery.
- (VD->getInit()->isValueDependent() || !VD->evaluateValue()))
+ (VD->getInit()->isValueDependent() || !VD->evaluateValue(ASTMutator)))
return true;
// Likewise, variables with tuple-like bindings are required if their
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 86913763ef9ff5..f49ef66cb43aea 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -2546,13 +2546,14 @@ EvaluatedStmt *VarDecl::getEvaluatedStmt() const {
return Init.dyn_cast<EvaluatedStmt *>();
}
-APValue *VarDecl::evaluateValue() const {
+APValue *VarDecl::evaluateValue(EvalASTMutator *ASTMutator) const {
SmallVector<PartialDiagnosticAt, 8> Notes;
- return evaluateValueImpl(Notes, hasConstantInitialization());
+ return evaluateValueImpl(Notes, hasConstantInitialization(), ASTMutator);
}
APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization) const {
+ bool IsConstantInitialization,
+ EvalASTMutator *ASTMutator) const {
EvaluatedStmt *Eval = ensureEvaluatedStmt();
const auto *Init = getInit();
@@ -2572,8 +2573,8 @@ APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
Eval->IsEvaluating = true;
ASTContext &Ctx = getASTContext();
- bool Result = Init->EvaluateAsInitializer(Eval->Evaluated, Ctx, this, Notes,
- IsConstantInitialization);
+ bool Result = Init->EvaluateAsInitializer(
+ Eval->Evaluated, Ctx, this, Notes, IsConstantInitialization, ASTMutator);
// In C++, or in C23 if we're initialising a 'constexpr' variable, this isn't
// a constant initializer if we produced notes. In that case, we can't keep
@@ -2636,7 +2637,8 @@ bool VarDecl::hasConstantInitialization() const {
}
bool VarDecl::checkForConstantInitialization(
- SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
+ SmallVectorImpl<PartialDiagnosticAt> &Notes,
+ EvalASTMutator *ASTMutator) const {
EvaluatedStmt *Eval = ensureEvaluatedStmt();
// If we ask for the value before we know whether we have a constant
// initializer, we can compute the wrong value (for example, due to
@@ -2651,7 +2653,7 @@ bool VarDecl::checkForConstantInitialization(
// Evaluate the initializer to check whether it's a constant expression.
Eval->HasConstantInitialization =
- evaluateValueImpl(Notes, true) && Notes.empty();
+ evaluateValueImpl(Notes, true, ASTMutator) && Notes.empty();
// If evaluation as a constant initializer failed, allow re-evaluation as a
// non-constant initializer if we later find we want the value.
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index d664c503655ba6..b9a075154b6d6f 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1004,6 +1004,11 @@ namespace {
EM_IgnoreSideEffects,
} EvalMode;
+ /// Implementation of an interface for AST mutation.
+ /// Basically something backed by Sema,
+ /// or nullptr if Sema is not available.
+ EvalASTMutator *ASTMutator;
+
/// Are we checking whether the expression is a potential constant
/// expression?
bool checkingPotentialConstantExpression() const override {
@@ -1017,7 +1022,8 @@ namespace {
return CheckingForUndefinedBehavior;
}
- EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode)
+ EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode,
+ EvalASTMutator *ASTMutator = nullptr)
: Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr),
CallStackDepth(0), NextCallIndex(1),
StepsLeft(C.getLangOpts().ConstexprStepLimit),
@@ -1027,13 +1033,15 @@ namespace {
/*CallExpr=*/nullptr, CallRef()),
EvaluatingDecl((const ValueDecl *)nullptr),
EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
- HasFoldFailureDiagnostic(false), EvalMode(Mode) {}
+ HasFoldFailureDiagnostic(false), EvalMode(Mode),
+ ASTMutator(ASTMutator) {}
~EvalInfo() {
discardCleanups();
}
ASTContext &getASTContext() const override { return Ctx; }
+ EvalASTMutator *getASTMutator() const { return ASTMutator; }
void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value,
EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) {
@@ -8328,6 +8336,12 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
+ if (!Definition && FD->getTemplateInstantiationPattern()) {
+ Info.getASTMutator()->InstantiateFunctionDefinition(
+ E->getExprLoc(), const_cast<FunctionDecl *>(FD),
+ /*Recursive=*/true, /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
+ Body = FD->getBody(Definition);
+ }
if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) ||
!HandleFunctionCall(E->getExprLoc(), Definition, This, E, Args, Call,
@@ -16669,7 +16683,8 @@ bool Expr::EvaluateAsConstantExpr(EvalResult &Result, const ASTContext &Ctx,
bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
const VarDecl *VD,
SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization) const {
+ bool IsConstantInitialization,
+ EvalASTMutator *ASTMutator) const {
assert(!isValueDependent() &&
"Expression evaluator can't be called on a dependent expression.");
@@ -16687,7 +16702,8 @@ bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
(IsConstantInitialization &&
(Ctx.getLangOpts().CPlusPlus || Ctx.getLangOpts().C23))
? EvalInfo::EM_ConstantExpression
- : EvalInfo::EM_ConstantFold);
+ : EvalInfo::EM_ConstantFold,
+ ASTMutator);
Info.setEvaluatingDecl(VD, Value);
Info.InConstantContext = IsConstantInitialization;
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 2b51765e80864a..328a8f7912a8ea 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -208,6 +208,8 @@ class SemaPPCallbacks : public PPCallbacks {
} // end namespace sema
} // end namespace clang
+SemaASTMutator::SemaASTMutator(Sema &SemaRef) : SemaRef(SemaRef) {}
+
const unsigned Sema::MaxAlignmentExponent;
const uint64_t Sema::MaximumAlignment;
@@ -221,7 +223,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
LateTemplateParser(nullptr), LateTemplateParserCleanup(nullptr),
OpaqueParser(nullptr), CurContext(nullptr), ExternalSource(nullptr),
StackHandler(Diags), CurScope(nullptr), Ident_super(nullptr),
- AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
+ ASTMutator(*this), AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
ARMPtr(std::make_unique<SemaARM>(*this)),
AVRPtr(std::make_unique<SemaAVR>(*this)),
BPFPtr(std::make_unique<SemaBPF>(*this)),
@@ -2798,3 +2800,10 @@ Attr *Sema::CreateAnnotationAttr(const ParsedAttr &AL) {
return CreateAnnotationAttr(AL, Str, Args);
}
+
+void SemaASTMutator::InstantiateFunctionDefinition(
+ SourceLocation PointOfInstantiation, FunctionDecl *Function, bool Recursive,
+ bool DefinitionRequired, bool AtEndOfTU) {
+ SemaRef.InstantiateFunctionDefinition(
+ PointOfInstantiation, Function, Recursive, DefinitionRequired, AtEndOfTU);
+}
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index f8e5f3c6d309d6..ea6ca66f8c69e9 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -14441,7 +14441,8 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
}
} else {
// Evaluate the initializer to see if it's a constant initializer.
- HasConstInit = var->checkForConstantInitialization(Notes);
+ HasConstInit =
+ var->checkForConstantInitialization(Notes, getASTMutator());
}
if (HasConstInit) {
@@ -14549,7 +14550,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
// If this variable must be emitted, add it as an initializer for the current
// module.
- if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
+ if (Context.DeclMustBeEmitted(var, getASTMutator()) && !ModuleScopes.empty())
Context.addModuleInitializer(ModuleScopes.back().Module, var);
// Build the bindings if this is a structured binding declaration.
diff --git a/clang/test/SemaCXX/constexpr-function-instantiation.cpp b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
new file mode 100644
index 00000000000000..43c2ced137474d
--- /dev/null
+++ b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify %s
+
+namespace GH73232 {
+namespace ex1 {
+template <typename T>
+constexpr void g(T);
+
+constexpr int f() {
+ g(0);
+ return 0;
+}
+
+template <typename T>
+constexpr void g(T) {}
+
+constexpr auto z = f();
+} // namespace ex1
+
+namespace ex2 {
+template <typename> constexpr static void fromType();
+
+void registerConverter() { fromType<int>(); }
+template <typename> struct QMetaTypeId {};
+template <typename T> constexpr void fromType() {
+ (void)QMetaTypeId<T>{};
+} // #1
+template <> struct QMetaTypeId<int> {}; // #20428
+} // namespace ex2
+} // namespace GH73232
\ No newline at end of file
>From 57de67a735c40557ba203ad1c3e46c6791dff706 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Wed, 6 Nov 2024 18:00:39 +0300
Subject: [PATCH 02/13] Add missing newline
---
clang/test/SemaCXX/constexpr-function-instantiation.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/clang/test/SemaCXX/constexpr-function-instantiation.cpp b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
index 43c2ced137474d..6c7e43f85cf6f9 100644
--- a/clang/test/SemaCXX/constexpr-function-instantiation.cpp
+++ b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
@@ -28,4 +28,4 @@ template <typename T> constexpr void fromType() {
} // #1
template <> struct QMetaTypeId<int> {}; // #20428
} // namespace ex2
-} // namespace GH73232
\ No newline at end of file
+} // namespace GH73232
>From 548298c8e2d1030b5d4edb8b548609b55aeba7f0 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Wed, 6 Nov 2024 18:14:45 +0300
Subject: [PATCH 03/13] Add missing semicolon
---
clang/include/clang/Sema/Sema.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 1c0c6949573335..61114b7107c650 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -357,7 +357,8 @@ struct SkipBodyInfo {
/// to modify AST, e.g. to instantiate templates.
struct SemaASTMutator : EvalASTMutator {
Sema &SemaRef;
- SemaASTMutator(Sema &SemaRef) void InstantiateFunctionDefinition(
+ SemaASTMutator(Sema &SemaRef);
+ void InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function,
bool Recursive, bool DefinitionRequired, bool AtEndOfTU) override;
};
>From 33092200cb15b3e095ee82d9001dd0e50eda668f Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Thu, 7 Nov 2024 19:35:41 +0300
Subject: [PATCH 04/13] Put ASTMutator inside ASTContext
---
clang/include/clang/AST/ASTContext.h | 21 ++++++++++++++++++-
clang/include/clang/AST/Decl.h | 20 +++---------------
clang/include/clang/AST/Expr.h | 3 +--
clang/lib/AST/ASTContext.cpp | 4 ++--
clang/lib/AST/Decl.cpp | 14 ++++++-------
clang/lib/AST/ExprConstant.cpp | 7 +++----
clang/lib/Sema/Sema.cpp | 6 ++++++
clang/lib/Sema/SemaDecl.cpp | 4 ++--
.../constexpr-function-instantiation.cpp | 20 +++++++++++-------
9 files changed, 56 insertions(+), 43 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index d143591de9f2cd..487b1647012ca8 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -98,6 +98,7 @@ class ParentMapContext;
struct ParsedTargetAttr;
class Preprocessor;
class ProfileList;
+class Sema;
class StoredDeclsMap;
class TargetAttr;
class TargetInfo;
@@ -182,6 +183,18 @@ struct TypeInfoChars {
}
};
+// Interface that allows constant evaluator to mutate AST.
+// When constant evaluation is triggered by Sema, it can supply a proper
+// implementation of this interface.
+struct EvalASTMutator {
+ virtual ~EvalASTMutator() = default;
+
+ virtual void
+ InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
+ FunctionDecl *Function, bool Recursive,
+ bool DefinitionRequired, bool AtEndOfTU) = 0;
+};
+
/// Holds long-lived AST nodes (such as types and decls) that can be
/// referred to throughout the semantic analysis of a file.
class ASTContext : public RefCountedBase<ASTContext> {
@@ -671,7 +684,11 @@ class ASTContext : public RefCountedBase<ASTContext> {
/// Keeps track of the deallocated DeclListNodes for future reuse.
DeclListNode *ListNodeFreeList = nullptr;
+ EvalASTMutator *ASTMutator = nullptr;
+
public:
+ EvalASTMutator *getASTMutator() const { return ASTMutator; }
+
IdentifierTable &Idents;
SelectorTable &Selectors;
Builtin::Context &BuiltinInfo;
@@ -3258,7 +3275,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
///
/// \returns true if the function/var must be CodeGen'ed/deserialized even if
/// it is not used.
- bool DeclMustBeEmitted(const Decl *D, EvalASTMutator *ASTMutator = nullptr);
+ bool DeclMustBeEmitted(const Decl *D);
/// Visits all versions of a multiversioned function with the passed
/// predicate.
@@ -3509,6 +3526,8 @@ OPT_LIST(V)
void ReleaseDeclContextMaps();
+ friend void injectASTMutatorIntoASTContext(Sema &, ASTContext &);
+
public:
enum PragmaSectionFlag : unsigned {
PSF_None = 0,
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 89a2833c82194d..83a4a2f4863fab 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -78,18 +78,6 @@ class UnresolvedSetImpl;
class VarTemplateDecl;
enum class ImplicitParamKind;
-/// Interface that allows constant evaluator to mutate AST.
-/// When constant evaluation is triggered by Sema, it can supply a proper
-/// implementation of this interface.
-struct EvalASTMutator {
- virtual ~EvalASTMutator() = default;
-
- virtual void
- InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
- FunctionDecl *Function, bool Recursive,
- bool DefinitionRequired, bool AtEndOfTU) = 0;
-};
-
/// The top declaration context.
class TranslationUnitDecl : public Decl,
public DeclContext,
@@ -1367,12 +1355,11 @@ class VarDecl : public DeclaratorDecl, public Redeclarable<VarDecl> {
/// Attempt to evaluate the value of the initializer attached to this
/// declaration, and produce notes explaining why it cannot be evaluated.
/// Returns a pointer to the value if evaluation succeeded, 0 otherwise.
- APValue *evaluateValue(EvalASTMutator *ASTMutator = nullptr) const;
+ APValue *evaluateValue() const;
private:
APValue *evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization,
- EvalASTMutator *ASTMutator = nullptr) const;
+ bool IsConstantInitialization) const;
public:
/// Return the already-evaluated value of this variable's
@@ -1405,8 +1392,7 @@ class VarDecl : public DeclaratorDecl, public Redeclarable<VarDecl> {
/// constant initializer. Should only be called once, after completing the
/// definition of the variable.
bool
- checkForConstantInitialization(SmallVectorImpl<PartialDiagnosticAt> &Notes,
- EvalASTMutator *ASTMutator = nullptr) const;
+ checkForConstantInitialization(SmallVectorImpl<PartialDiagnosticAt> &Notes) const;
void setInitStyle(InitializationStyle Style) {
VarDeclBits.InitStyle = Style;
diff --git a/clang/include/clang/AST/Expr.h b/clang/include/clang/AST/Expr.h
index ccf7fd226b5a8f..466c65a9685ad3 100644
--- a/clang/include/clang/AST/Expr.h
+++ b/clang/include/clang/AST/Expr.h
@@ -734,8 +734,7 @@ class Expr : public ValueStmt {
bool EvaluateAsInitializer(APValue &Result, const ASTContext &Ctx,
const VarDecl *VD,
SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitializer,
- EvalASTMutator *ASTMutator = nullptr) const;
+ bool IsConstantInitializer) const;
/// EvaluateWithSubstitution - Evaluate an expression as if from the context
/// of a call to the given function with the given arguments, inside an
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 0aaf23af28d3d6..69892bda42b256 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -12522,7 +12522,7 @@ GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) const {
basicGVALinkageForVariable(*this, VD)));
}
-bool ASTContext::DeclMustBeEmitted(const Decl *D, EvalASTMutator *ASTMutator) {
+bool ASTContext::DeclMustBeEmitted(const Decl *D) {
if (const auto *VD = dyn_cast<VarDecl>(D)) {
if (!VD->isFileVarDecl())
return false;
@@ -12627,7 +12627,7 @@ bool ASTContext::DeclMustBeEmitted(const Decl *D, EvalASTMutator *ASTMutator) {
// Variables that have initialization with side-effects are required.
if (VD->getInit() && VD->getInit()->HasSideEffects(*this) &&
// We can get a value-dependent initializer during error recovery.
- (VD->getInit()->isValueDependent() || !VD->evaluateValue(ASTMutator)))
+ (VD->getInit()->isValueDependent() || !VD->evaluateValue()))
return true;
// Likewise, variables with tuple-like bindings are required if their
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index f49ef66cb43aea..d264441fe74e7e 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -2546,14 +2546,13 @@ EvaluatedStmt *VarDecl::getEvaluatedStmt() const {
return Init.dyn_cast<EvaluatedStmt *>();
}
-APValue *VarDecl::evaluateValue(EvalASTMutator *ASTMutator) const {
+APValue *VarDecl::evaluateValue() const {
SmallVector<PartialDiagnosticAt, 8> Notes;
- return evaluateValueImpl(Notes, hasConstantInitialization(), ASTMutator);
+ return evaluateValueImpl(Notes, hasConstantInitialization());
}
APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization,
- EvalASTMutator *ASTMutator) const {
+ bool IsConstantInitialization) const {
EvaluatedStmt *Eval = ensureEvaluatedStmt();
const auto *Init = getInit();
@@ -2574,7 +2573,7 @@ APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
ASTContext &Ctx = getASTContext();
bool Result = Init->EvaluateAsInitializer(
- Eval->Evaluated, Ctx, this, Notes, IsConstantInitialization, ASTMutator);
+ Eval->Evaluated, Ctx, this, Notes, IsConstantInitialization);
// In C++, or in C23 if we're initialising a 'constexpr' variable, this isn't
// a constant initializer if we produced notes. In that case, we can't keep
@@ -2637,8 +2636,7 @@ bool VarDecl::hasConstantInitialization() const {
}
bool VarDecl::checkForConstantInitialization(
- SmallVectorImpl<PartialDiagnosticAt> &Notes,
- EvalASTMutator *ASTMutator) const {
+ SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
EvaluatedStmt *Eval = ensureEvaluatedStmt();
// If we ask for the value before we know whether we have a constant
// initializer, we can compute the wrong value (for example, due to
@@ -2653,7 +2651,7 @@ bool VarDecl::checkForConstantInitialization(
// Evaluate the initializer to check whether it's a constant expression.
Eval->HasConstantInitialization =
- evaluateValueImpl(Notes, true, ASTMutator) && Notes.empty();
+ evaluateValueImpl(Notes, true) && Notes.empty();
// If evaluation as a constant initializer failed, allow re-evaluation as a
// non-constant initializer if we later find we want the value.
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index b9a075154b6d6f..c167e6fa8e92a4 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -8336,7 +8336,7 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
- if (!Definition && FD->getTemplateInstantiationPattern()) {
+ if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getASTMutator() && !Definition && FD->getTemplateInstantiationPattern()) {
Info.getASTMutator()->InstantiateFunctionDefinition(
E->getExprLoc(), const_cast<FunctionDecl *>(FD),
/*Recursive=*/true, /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
@@ -16683,8 +16683,7 @@ bool Expr::EvaluateAsConstantExpr(EvalResult &Result, const ASTContext &Ctx,
bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
const VarDecl *VD,
SmallVectorImpl<PartialDiagnosticAt> &Notes,
- bool IsConstantInitialization,
- EvalASTMutator *ASTMutator) const {
+ bool IsConstantInitialization) const {
assert(!isValueDependent() &&
"Expression evaluator can't be called on a dependent expression.");
@@ -16703,7 +16702,7 @@ bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
(Ctx.getLangOpts().CPlusPlus || Ctx.getLangOpts().C23))
? EvalInfo::EM_ConstantExpression
: EvalInfo::EM_ConstantFold,
- ASTMutator);
+ Ctx.getASTMutator());
Info.setEvaluatingDecl(VD, Value);
Info.InConstantContext = IsConstantInitialization;
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 328a8f7912a8ea..ab58a54541c628 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -208,6 +208,10 @@ class SemaPPCallbacks : public PPCallbacks {
} // end namespace sema
} // end namespace clang
+void clang::injectASTMutatorIntoASTContext(Sema &S, ASTContext &Context) {
+ Context.ASTMutator = S.getASTMutator();
+}
+
SemaASTMutator::SemaASTMutator(Sema &SemaRef) : SemaRef(SemaRef) {}
const unsigned Sema::MaxAlignmentExponent;
@@ -300,6 +304,8 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
SemaPPCallbackHandler->set(*this);
CurFPFeatures.setFPEvalMethod(PP.getCurrentFPEvalMethod());
+
+ injectASTMutatorIntoASTContext(*this, Context);
}
// Anchor Sema's type info to this TU.
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index ea6ca66f8c69e9..3d95fd7013fbdd 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -14442,7 +14442,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
} else {
// Evaluate the initializer to see if it's a constant initializer.
HasConstInit =
- var->checkForConstantInitialization(Notes, getASTMutator());
+ var->checkForConstantInitialization(Notes);
}
if (HasConstInit) {
@@ -14550,7 +14550,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
// If this variable must be emitted, add it as an initializer for the current
// module.
- if (Context.DeclMustBeEmitted(var, getASTMutator()) && !ModuleScopes.empty())
+ if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
Context.addModuleInitializer(ModuleScopes.back().Module, var);
// Build the bindings if this is a structured binding declaration.
diff --git a/clang/test/SemaCXX/constexpr-function-instantiation.cpp b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
index 6c7e43f85cf6f9..aec14e938be9f5 100644
--- a/clang/test/SemaCXX/constexpr-function-instantiation.cpp
+++ b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
@@ -1,21 +1,27 @@
-// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s
-// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify %s
-// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify %s
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify=cxx20-23 %s
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=cxx20-23 %s
+// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=cxx26 %s
+
+// cxx26-no-diagnostics
namespace GH73232 {
namespace ex1 {
template <typename T>
-constexpr void g(T);
+constexpr void g(T); // #ex1-g-decl
constexpr int f() {
- g(0);
- return 0;
+ g(0); // #ex1-g-call
+ return 0;
}
template <typename T>
constexpr void g(T) {}
-constexpr auto z = f();
+constexpr auto z = f(); // #ex1-z-defn
+// cxx20-23-error at -1 {{constexpr variable 'z' must be initialized by a constant expression}}
+// cxx20-23-note@#ex1-g-call {{undefined function 'g<int>' cannot be used in a constant expression}}
+// cxx20-23-note@#ex1-z-defn {{in call to 'f()'}}
+// cxx20-23-note@#ex1-g-decl {{declared here}}
} // namespace ex1
namespace ex2 {
>From 54da0e85a0095e6b1c40a6bb51446c4feb20e67b Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Thu, 7 Nov 2024 20:08:04 +0300
Subject: [PATCH 05/13] Don't store `ASTMutator` inside `EvalInfo`
---
clang/include/clang/AST/ASTContext.h | 11 +++++++++--
clang/include/clang/AST/Decl.h | 4 ++--
clang/lib/AST/Decl.cpp | 4 ++--
clang/lib/AST/ExprConstant.cpp | 19 ++++++-------------
clang/lib/Sema/Sema.cpp | 3 +++
clang/lib/Sema/SemaDecl.cpp | 3 +--
6 files changed, 23 insertions(+), 21 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index 487b1647012ca8..b5895627213d10 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -184,8 +184,7 @@ struct TypeInfoChars {
};
// Interface that allows constant evaluator to mutate AST.
-// When constant evaluation is triggered by Sema, it can supply a proper
-// implementation of this interface.
+// Sema is the only entity that can implement this.
struct EvalASTMutator {
virtual ~EvalASTMutator() = default;
@@ -684,9 +683,14 @@ class ASTContext : public RefCountedBase<ASTContext> {
/// Keeps track of the deallocated DeclListNodes for future reuse.
DeclListNode *ListNodeFreeList = nullptr;
+ /// Implementation of the interface that Sema provides during its
+ /// construction.
EvalASTMutator *ASTMutator = nullptr;
public:
+ /// Returns an object that is capable of modifying AST,
+ /// or nullptr if it's not available. The latter happens when
+ /// Sema is not available.
EvalASTMutator *getASTMutator() const { return ASTMutator; }
IdentifierTable &Idents;
@@ -3526,6 +3530,9 @@ OPT_LIST(V)
void ReleaseDeclContextMaps();
+ /// This is a function that is implemented in the Sema layer,
+ /// that needs friendship to initialize ASTMutator without this capability
+ /// being available in the public interface of ASTContext.
friend void injectASTMutatorIntoASTContext(Sema &, ASTContext &);
public:
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 83a4a2f4863fab..7ff35d73df5997 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -1391,8 +1391,8 @@ class VarDecl : public DeclaratorDecl, public Redeclarable<VarDecl> {
/// Evaluate the initializer of this variable to determine whether it's a
/// constant initializer. Should only be called once, after completing the
/// definition of the variable.
- bool
- checkForConstantInitialization(SmallVectorImpl<PartialDiagnosticAt> &Notes) const;
+ bool checkForConstantInitialization(
+ SmallVectorImpl<PartialDiagnosticAt> &Notes) const;
void setInitStyle(InitializationStyle Style) {
VarDeclBits.InitStyle = Style;
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index d264441fe74e7e..86913763ef9ff5 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -2572,8 +2572,8 @@ APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
Eval->IsEvaluating = true;
ASTContext &Ctx = getASTContext();
- bool Result = Init->EvaluateAsInitializer(
- Eval->Evaluated, Ctx, this, Notes, IsConstantInitialization);
+ bool Result = Init->EvaluateAsInitializer(Eval->Evaluated, Ctx, this, Notes,
+ IsConstantInitialization);
// In C++, or in C23 if we're initialising a 'constexpr' variable, this isn't
// a constant initializer if we produced notes. In that case, we can't keep
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index c167e6fa8e92a4..701dca6bf373ee 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1004,11 +1004,6 @@ namespace {
EM_IgnoreSideEffects,
} EvalMode;
- /// Implementation of an interface for AST mutation.
- /// Basically something backed by Sema,
- /// or nullptr if Sema is not available.
- EvalASTMutator *ASTMutator;
-
/// Are we checking whether the expression is a potential constant
/// expression?
bool checkingPotentialConstantExpression() const override {
@@ -1022,8 +1017,7 @@ namespace {
return CheckingForUndefinedBehavior;
}
- EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode,
- EvalASTMutator *ASTMutator = nullptr)
+ EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode)
: Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr),
CallStackDepth(0), NextCallIndex(1),
StepsLeft(C.getLangOpts().ConstexprStepLimit),
@@ -1033,15 +1027,14 @@ namespace {
/*CallExpr=*/nullptr, CallRef()),
EvaluatingDecl((const ValueDecl *)nullptr),
EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
- HasFoldFailureDiagnostic(false), EvalMode(Mode),
- ASTMutator(ASTMutator) {}
+ HasFoldFailureDiagnostic(false), EvalMode(Mode) {}
~EvalInfo() {
discardCleanups();
}
ASTContext &getASTContext() const override { return Ctx; }
- EvalASTMutator *getASTMutator() const { return ASTMutator; }
+ EvalASTMutator *getASTMutator() const { return Ctx.getASTMutator(); }
void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value,
EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) {
@@ -8336,7 +8329,8 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
- if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getASTMutator() && !Definition && FD->getTemplateInstantiationPattern()) {
+ if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getASTMutator() &&
+ !Definition && FD->getTemplateInstantiationPattern()) {
Info.getASTMutator()->InstantiateFunctionDefinition(
E->getExprLoc(), const_cast<FunctionDecl *>(FD),
/*Recursive=*/true, /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
@@ -16701,8 +16695,7 @@ bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
(IsConstantInitialization &&
(Ctx.getLangOpts().CPlusPlus || Ctx.getLangOpts().C23))
? EvalInfo::EM_ConstantExpression
- : EvalInfo::EM_ConstantFold,
- Ctx.getASTMutator());
+ : EvalInfo::EM_ConstantFold);
Info.setEvaluatingDecl(VD, Value);
Info.InConstantContext = IsConstantInitialization;
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index ab58a54541c628..41eff868a3fafb 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -305,6 +305,9 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
CurFPFeatures.setFPEvalMethod(PP.getCurrentFPEvalMethod());
+ /// Initialize ASTMutator within ASTContext.
+ /// This is very intentionally not a part of public interface
+ /// of ASTContext.
injectASTMutatorIntoASTContext(*this, Context);
}
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 3d95fd7013fbdd..f8e5f3c6d309d6 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -14441,8 +14441,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
}
} else {
// Evaluate the initializer to see if it's a constant initializer.
- HasConstInit =
- var->checkForConstantInitialization(Notes);
+ HasConstInit = var->checkForConstantInitialization(Notes);
}
if (HasConstInit) {
>From 4d91ede45c51acc0dee61695ef19e1b8f0fcfb72 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Fri, 8 Nov 2024 18:20:22 +0300
Subject: [PATCH 06/13] Remove `Sema` from `ASTContext`
---
clang/include/clang/AST/ASTContext.h | 3 +--
clang/lib/Sema/Sema.cpp | 7 ++++---
2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index b5895627213d10..d2d4e13ee9b7e3 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -98,7 +98,6 @@ class ParentMapContext;
struct ParsedTargetAttr;
class Preprocessor;
class ProfileList;
-class Sema;
class StoredDeclsMap;
class TargetAttr;
class TargetInfo;
@@ -3533,7 +3532,7 @@ OPT_LIST(V)
/// This is a function that is implemented in the Sema layer,
/// that needs friendship to initialize ASTMutator without this capability
/// being available in the public interface of ASTContext.
- friend void injectASTMutatorIntoASTContext(Sema &, ASTContext &);
+ friend void injectASTMutatorIntoASTContext(ASTContext &, EvalASTMutator *);
public:
enum PragmaSectionFlag : unsigned {
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 41eff868a3fafb..9469be0ba1e8cc 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -208,8 +208,9 @@ class SemaPPCallbacks : public PPCallbacks {
} // end namespace sema
} // end namespace clang
-void clang::injectASTMutatorIntoASTContext(Sema &S, ASTContext &Context) {
- Context.ASTMutator = S.getASTMutator();
+void clang::injectASTMutatorIntoASTContext(ASTContext &Context,
+ EvalASTMutator *ASTMutator) {
+ Context.ASTMutator = ASTMutator;
}
SemaASTMutator::SemaASTMutator(Sema &SemaRef) : SemaRef(SemaRef) {}
@@ -308,7 +309,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
/// Initialize ASTMutator within ASTContext.
/// This is very intentionally not a part of public interface
/// of ASTContext.
- injectASTMutatorIntoASTContext(*this, Context);
+ injectASTMutatorIntoASTContext(Context, getASTMutator());
}
// Anchor Sema's type info to this TU.
>From 98945b41b480b2f51cf95b2705e9750be997d5bc Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Wed, 13 Nov 2024 18:46:58 +0300
Subject: [PATCH 07/13] Rename ASTMutator to SemaProxy
---
clang/include/clang/AST/ASTContext.h | 18 +++++++++---------
clang/include/clang/Sema/Sema.h | 16 ++++++++--------
clang/lib/AST/ExprConstant.cpp | 6 +++---
clang/lib/Sema/Sema.cpp | 12 ++++++------
4 files changed, 26 insertions(+), 26 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index d2d4e13ee9b7e3..944140542b11b4 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -182,10 +182,10 @@ struct TypeInfoChars {
}
};
-// Interface that allows constant evaluator to mutate AST.
-// Sema is the only entity that can implement this.
-struct EvalASTMutator {
- virtual ~EvalASTMutator() = default;
+// Interface that allows constant evaluator to call Sema
+// and mutate the AST.
+struct SemaProxy {
+ virtual ~SemaProxy() = default;
virtual void
InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
@@ -684,13 +684,13 @@ class ASTContext : public RefCountedBase<ASTContext> {
/// Implementation of the interface that Sema provides during its
/// construction.
- EvalASTMutator *ASTMutator = nullptr;
+ SemaProxy *ASTMutator = nullptr;
public:
/// Returns an object that is capable of modifying AST,
/// or nullptr if it's not available. The latter happens when
/// Sema is not available.
- EvalASTMutator *getASTMutator() const { return ASTMutator; }
+ SemaProxy *getSemaProxy() const { return ASTMutator; }
IdentifierTable &Idents;
SelectorTable &Selectors;
@@ -3530,9 +3530,9 @@ OPT_LIST(V)
void ReleaseDeclContextMaps();
/// This is a function that is implemented in the Sema layer,
- /// that needs friendship to initialize ASTMutator without this capability
- /// being available in the public interface of ASTContext.
- friend void injectASTMutatorIntoASTContext(ASTContext &, EvalASTMutator *);
+ /// that needs friendship to initialize SemaProxy without this capability
+ /// being exposed in the public interface of ASTContext.
+ friend void injectSemaProxyIntoASTContext(ASTContext &, SemaProxy *);
public:
enum PragmaSectionFlag : unsigned {
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 61114b7107c650..7fe05a8991acfa 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -353,11 +353,11 @@ struct SkipBodyInfo {
NamedDecl *New = nullptr;
};
-/// Implementation of EvalASTMutator interface that enables constant evaluator
-/// to modify AST, e.g. to instantiate templates.
-struct SemaASTMutator : EvalASTMutator {
+/// Implementation of SemaProxy interface that enables constant evaluator
+/// to call Sema and modify AST, e.g. to instantiate templates.
+struct SemaProxyImpl : SemaProxy {
Sema &SemaRef;
- SemaASTMutator(Sema &SemaRef);
+ SemaProxyImpl(Sema &SemaRef);
void InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function,
bool Recursive, bool DefinitionRequired, bool AtEndOfTU) override;
@@ -1053,8 +1053,8 @@ class Sema final : public SemaBase {
/// CurContext - This is the current declaration context of parsing.
DeclContext *CurContext;
- /// Get a Sema implementation of EvalASTMutator interface.
- SemaASTMutator *getASTMutator() { return &ASTMutator; }
+ /// Get a Sema implementation of SemaProxy interface.
+ SemaProxyImpl *getSemaProxy() { return &SemaProxy; }
SemaAMDGPU &AMDGPU() {
assert(AMDGPUPtr);
@@ -1213,9 +1213,9 @@ class Sema final : public SemaBase {
mutable IdentifierInfo *Ident_super;
- /// EvalASTMutator implementation that can be passed to constant evaluator
+ /// SemaProxy implementation that can be passed to constant evaluator
/// to enable it to do AST mutations, e.g. template instantiation.
- SemaASTMutator ASTMutator;
+ SemaProxyImpl SemaProxy;
std::unique_ptr<SemaAMDGPU> AMDGPUPtr;
std::unique_ptr<SemaARM> ARMPtr;
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 701dca6bf373ee..c118fba87e615f 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1034,7 +1034,7 @@ namespace {
}
ASTContext &getASTContext() const override { return Ctx; }
- EvalASTMutator *getASTMutator() const { return Ctx.getASTMutator(); }
+ SemaProxy *getSemaProxy() const { return Ctx.getSemaProxy(); }
void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value,
EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) {
@@ -8329,9 +8329,9 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
- if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getASTMutator() &&
+ if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getSemaProxy() &&
!Definition && FD->getTemplateInstantiationPattern()) {
- Info.getASTMutator()->InstantiateFunctionDefinition(
+ Info.getSemaProxy()->InstantiateFunctionDefinition(
E->getExprLoc(), const_cast<FunctionDecl *>(FD),
/*Recursive=*/true, /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
Body = FD->getBody(Definition);
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 9469be0ba1e8cc..d5f65470a02486 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -208,12 +208,12 @@ class SemaPPCallbacks : public PPCallbacks {
} // end namespace sema
} // end namespace clang
-void clang::injectASTMutatorIntoASTContext(ASTContext &Context,
- EvalASTMutator *ASTMutator) {
+void clang::injectSemaProxyIntoASTContext(ASTContext &Context,
+ SemaProxy *ASTMutator) {
Context.ASTMutator = ASTMutator;
}
-SemaASTMutator::SemaASTMutator(Sema &SemaRef) : SemaRef(SemaRef) {}
+SemaProxyImpl::SemaProxyImpl(Sema &SemaRef) : SemaRef(SemaRef) {}
const unsigned Sema::MaxAlignmentExponent;
const uint64_t Sema::MaximumAlignment;
@@ -228,7 +228,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
LateTemplateParser(nullptr), LateTemplateParserCleanup(nullptr),
OpaqueParser(nullptr), CurContext(nullptr), ExternalSource(nullptr),
StackHandler(Diags), CurScope(nullptr), Ident_super(nullptr),
- ASTMutator(*this), AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
+ SemaProxy(*this), AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
ARMPtr(std::make_unique<SemaARM>(*this)),
AVRPtr(std::make_unique<SemaAVR>(*this)),
BPFPtr(std::make_unique<SemaBPF>(*this)),
@@ -309,7 +309,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
/// Initialize ASTMutator within ASTContext.
/// This is very intentionally not a part of public interface
/// of ASTContext.
- injectASTMutatorIntoASTContext(Context, getASTMutator());
+ injectSemaProxyIntoASTContext(Context, getSemaProxy());
}
// Anchor Sema's type info to this TU.
@@ -2811,7 +2811,7 @@ Attr *Sema::CreateAnnotationAttr(const ParsedAttr &AL) {
return CreateAnnotationAttr(AL, Str, Args);
}
-void SemaASTMutator::InstantiateFunctionDefinition(
+void SemaProxyImpl::InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function, bool Recursive,
bool DefinitionRequired, bool AtEndOfTU) {
SemaRef.InstantiateFunctionDefinition(
>From b4e605ac1afe57c39d9b2b145873fbe306fd0ddb Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Fri, 15 Nov 2024 17:58:02 +0300
Subject: [PATCH 08/13] Address feedback
---
clang/include/clang/AST/ASTContext.h | 27 ++++++++++++++-----
.../include/clang/Basic/DiagnosticASTKinds.td | 5 ++++
clang/include/clang/Basic/DiagnosticGroups.td | 1 +
clang/include/clang/Sema/Sema.h | 14 +++-------
clang/lib/AST/ASTContext.cpp | 18 ++++++++++---
clang/lib/AST/ExprConstant.cpp | 10 +++----
clang/lib/Sema/Sema.cpp | 17 ++++++------
7 files changed, 57 insertions(+), 35 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index 944140542b11b4..d05d55206c55ee 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -182,15 +182,14 @@ struct TypeInfoChars {
}
};
-// Interface that allows constant evaluator to call Sema
-// and mutate the AST.
+/// Interface that allows constant evaluator to call Sema
+/// and mutate the AST.
struct SemaProxy {
virtual ~SemaProxy() = default;
virtual void
InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
- FunctionDecl *Function, bool Recursive,
- bool DefinitionRequired, bool AtEndOfTU) = 0;
+ FunctionDecl *Function) = 0;
};
/// Holds long-lived AST nodes (such as types and decls) that can be
@@ -684,13 +683,16 @@ class ASTContext : public RefCountedBase<ASTContext> {
/// Implementation of the interface that Sema provides during its
/// construction.
- SemaProxy *ASTMutator = nullptr;
+ std::unique_ptr<SemaProxy> SemaProxyPtr;
public:
/// Returns an object that is capable of modifying AST,
/// or nullptr if it's not available. The latter happens when
/// Sema is not available.
- SemaProxy *getSemaProxy() const { return ASTMutator; }
+ SemaProxy &getSemaProxy() const {
+ assert(SemaProxyPtr);
+ return *SemaProxyPtr;
+ }
IdentifierTable &Idents;
SelectorTable &Selectors;
@@ -3532,7 +3534,8 @@ OPT_LIST(V)
/// This is a function that is implemented in the Sema layer,
/// that needs friendship to initialize SemaProxy without this capability
/// being exposed in the public interface of ASTContext.
- friend void injectSemaProxyIntoASTContext(ASTContext &, SemaProxy *);
+ friend void injectSemaProxyIntoASTContext(ASTContext &,
+ std::unique_ptr<SemaProxy>);
public:
enum PragmaSectionFlag : unsigned {
@@ -3601,6 +3604,16 @@ inline Selector GetUnarySelector(StringRef name, ASTContext &Ctx) {
return Ctx.Selectors.getSelector(1, &II);
}
+/// Placeholder implementation that issues a diagnostic on any usage.
+struct UnimplementedSemaProxy : SemaProxy {
+ ASTContext &Ctx;
+ explicit UnimplementedSemaProxy(ASTContext &);
+ virtual ~UnimplementedSemaProxy() = default;
+
+ void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
+ FunctionDecl *Function) override;
+};
+
} // namespace clang
// operator new and delete aren't allowed inside namespaces.
diff --git a/clang/include/clang/Basic/DiagnosticASTKinds.td b/clang/include/clang/Basic/DiagnosticASTKinds.td
index 6a658cf14356f5..58ded8d0b2a7fc 100644
--- a/clang/include/clang/Basic/DiagnosticASTKinds.td
+++ b/clang/include/clang/Basic/DiagnosticASTKinds.td
@@ -1025,4 +1025,9 @@ def warn_unpacked_field
def warn_unaligned_access : Warning<
"field %1 within %0 is less aligned than %2 and is usually due to %0 being "
"packed, which can lead to unaligned accesses">, InGroup<UnalignedAccess>, DefaultIgnore;
+
+def warn_side_effects_on_ast_unavailable : Warning<
+ "%select{instantiation of a function template}0"
+ " did not happen, because internal program representation is immutable">,
+ InGroup<SideEffectsUnavailable>;
}
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 72eada50a56cc9..4119c90352137f 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -629,6 +629,7 @@ def Packed : DiagGroup<"packed", [PackedNonPod]>;
def PaddedBitField : DiagGroup<"padded-bitfield">;
def Padded : DiagGroup<"padded", [PaddedBitField]>;
def UnalignedAccess : DiagGroup<"unaligned-access">;
+def SideEffectsUnavailable : DiagGroup<"side-effects-unavailable">;
def PessimizingMove : DiagGroup<"pessimizing-move">;
def ReturnStdMove : DiagGroup<"return-std-move">;
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 7fe05a8991acfa..dfde0e69323a65 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -357,10 +357,9 @@ struct SkipBodyInfo {
/// to call Sema and modify AST, e.g. to instantiate templates.
struct SemaProxyImpl : SemaProxy {
Sema &SemaRef;
- SemaProxyImpl(Sema &SemaRef);
- void InstantiateFunctionDefinition(
- SourceLocation PointOfInstantiation, FunctionDecl *Function,
- bool Recursive, bool DefinitionRequired, bool AtEndOfTU) override;
+ explicit SemaProxyImpl(Sema &SemaRef);
+ void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
+ FunctionDecl *Function) override;
};
/// Describes the result of template argument deduction.
@@ -1053,9 +1052,6 @@ class Sema final : public SemaBase {
/// CurContext - This is the current declaration context of parsing.
DeclContext *CurContext;
- /// Get a Sema implementation of SemaProxy interface.
- SemaProxyImpl *getSemaProxy() { return &SemaProxy; }
-
SemaAMDGPU &AMDGPU() {
assert(AMDGPUPtr);
return *AMDGPUPtr;
@@ -1213,10 +1209,6 @@ class Sema final : public SemaBase {
mutable IdentifierInfo *Ident_super;
- /// SemaProxy implementation that can be passed to constant evaluator
- /// to enable it to do AST mutations, e.g. template instantiation.
- SemaProxyImpl SemaProxy;
-
std::unique_ptr<SemaAMDGPU> AMDGPUPtr;
std::unique_ptr<SemaARM> ARMPtr;
std::unique_ptr<SemaAVR> AVRPtr;
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 69892bda42b256..b61e064bc255bd 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -51,6 +51,7 @@
#include "clang/Basic/AddressSpaces.h"
#include "clang/Basic/Builtins.h"
#include "clang/Basic/CommentOptions.h"
+#include "clang/Basic/DiagnosticAST.h"
#include "clang/Basic/ExceptionSpecificationType.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/LLVM.h"
@@ -902,9 +903,11 @@ ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
LangOpts.XRayNeverInstrumentFiles,
LangOpts.XRayAttrListFiles, SM)),
ProfList(new ProfileList(LangOpts.ProfileListFiles, SM)),
- PrintingPolicy(LOpts), Idents(idents), Selectors(sels),
- BuiltinInfo(builtins), TUKind(TUKind), DeclarationNames(*this),
- Comments(SM), CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
+ PrintingPolicy(LOpts),
+ SemaProxyPtr(std::make_unique<UnimplementedSemaProxy>(*this)),
+ Idents(idents), Selectors(sels), BuiltinInfo(builtins), TUKind(TUKind),
+ DeclarationNames(*this), Comments(SM),
+ CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
CompCategories(this_()), LastSDM(nullptr, 0) {
addTranslationUnitDecl();
}
@@ -14492,3 +14495,12 @@ bool ASTContext::useAbbreviatedThunkName(GlobalDecl VirtualMethodDecl,
ThunksToBeAbbreviated[VirtualMethodDecl] = std::move(SimplifiedThunkNames);
return Result;
}
+
+UnimplementedSemaProxy::UnimplementedSemaProxy(ASTContext &Ctx) : Ctx(Ctx) {}
+
+void UnimplementedSemaProxy::InstantiateFunctionDefinition(
+ SourceLocation PointOfInstantiation, FunctionDecl *Function) {
+ Ctx.getDiagnostics().Report(PointOfInstantiation,
+ diag::warn_side_effects_on_ast_unavailable)
+ << 0;
+}
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index c118fba87e615f..4d523d9f15e9c4 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1034,7 +1034,7 @@ namespace {
}
ASTContext &getASTContext() const override { return Ctx; }
- SemaProxy *getSemaProxy() const { return Ctx.getSemaProxy(); }
+ SemaProxy &getSemaProxy() const { return Ctx.getSemaProxy(); }
void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value,
EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) {
@@ -8329,11 +8329,9 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
- if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getSemaProxy() &&
- !Definition && FD->getTemplateInstantiationPattern()) {
- Info.getSemaProxy()->InstantiateFunctionDefinition(
- E->getExprLoc(), const_cast<FunctionDecl *>(FD),
- /*Recursive=*/true, /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
+ if (!Definition && FD->getTemplateInstantiationPattern()) {
+ Info.getSemaProxy().InstantiateFunctionDefinition(
+ E->getExprLoc(), const_cast<FunctionDecl *>(FD));
Body = FD->getBody(Definition);
}
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index d5f65470a02486..793e6ed3d059bd 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -209,8 +209,8 @@ class SemaPPCallbacks : public PPCallbacks {
} // end namespace clang
void clang::injectSemaProxyIntoASTContext(ASTContext &Context,
- SemaProxy *ASTMutator) {
- Context.ASTMutator = ASTMutator;
+ std::unique_ptr<SemaProxy> ProxyPtr) {
+ Context.SemaProxyPtr = std::move(ProxyPtr);
}
SemaProxyImpl::SemaProxyImpl(Sema &SemaRef) : SemaRef(SemaRef) {}
@@ -228,7 +228,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
LateTemplateParser(nullptr), LateTemplateParserCleanup(nullptr),
OpaqueParser(nullptr), CurContext(nullptr), ExternalSource(nullptr),
StackHandler(Diags), CurScope(nullptr), Ident_super(nullptr),
- SemaProxy(*this), AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
+ AMDGPUPtr(std::make_unique<SemaAMDGPU>(*this)),
ARMPtr(std::make_unique<SemaARM>(*this)),
AVRPtr(std::make_unique<SemaAVR>(*this)),
BPFPtr(std::make_unique<SemaBPF>(*this)),
@@ -306,10 +306,11 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
CurFPFeatures.setFPEvalMethod(PP.getCurrentFPEvalMethod());
- /// Initialize ASTMutator within ASTContext.
+ /// Initialize SemaProxyPtr within ASTContext.
/// This is very intentionally not a part of public interface
/// of ASTContext.
- injectSemaProxyIntoASTContext(Context, getSemaProxy());
+ injectSemaProxyIntoASTContext(Context,
+ std::make_unique<SemaProxyImpl>(*this));
}
// Anchor Sema's type info to this TU.
@@ -2812,8 +2813,8 @@ Attr *Sema::CreateAnnotationAttr(const ParsedAttr &AL) {
}
void SemaProxyImpl::InstantiateFunctionDefinition(
- SourceLocation PointOfInstantiation, FunctionDecl *Function, bool Recursive,
- bool DefinitionRequired, bool AtEndOfTU) {
+ SourceLocation PointOfInstantiation, FunctionDecl *Function) {
SemaRef.InstantiateFunctionDefinition(
- PointOfInstantiation, Function, Recursive, DefinitionRequired, AtEndOfTU);
+ PointOfInstantiation, Function, /*Recursive=*/true,
+ /*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
}
>From 57bed5d3f61decf192edc4686c35202bd69b59f8 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Fri, 15 Nov 2024 21:56:43 +0300
Subject: [PATCH 09/13] Replace the diagnostic with llvm_unreachable that can
be disabled
---
clang/include/clang/AST/ASTContext.h | 6 ++++++
clang/include/clang/Basic/DiagnosticASTKinds.td | 5 -----
clang/include/clang/Basic/DiagnosticGroups.td | 1 -
clang/lib/AST/ASTContext.cpp | 15 ++++++++++++---
clang/lib/Sema/Sema.cpp | 2 ++
5 files changed, 20 insertions(+), 9 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index d05d55206c55ee..d7a9197500b30e 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -187,9 +187,15 @@ struct TypeInfoChars {
struct SemaProxy {
virtual ~SemaProxy() = default;
+ bool getIgnoreSideEffectsOnAST();
+ void setIgnoreSideEffectsOnAST(bool ignore = true);
+
virtual void
InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
FunctionDecl *Function) = 0;
+
+private:
+ bool IgnoreSideEffectsOnAST = false;
};
/// Holds long-lived AST nodes (such as types and decls) that can be
diff --git a/clang/include/clang/Basic/DiagnosticASTKinds.td b/clang/include/clang/Basic/DiagnosticASTKinds.td
index 58ded8d0b2a7fc..6a658cf14356f5 100644
--- a/clang/include/clang/Basic/DiagnosticASTKinds.td
+++ b/clang/include/clang/Basic/DiagnosticASTKinds.td
@@ -1025,9 +1025,4 @@ def warn_unpacked_field
def warn_unaligned_access : Warning<
"field %1 within %0 is less aligned than %2 and is usually due to %0 being "
"packed, which can lead to unaligned accesses">, InGroup<UnalignedAccess>, DefaultIgnore;
-
-def warn_side_effects_on_ast_unavailable : Warning<
- "%select{instantiation of a function template}0"
- " did not happen, because internal program representation is immutable">,
- InGroup<SideEffectsUnavailable>;
}
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 4119c90352137f..72eada50a56cc9 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -629,7 +629,6 @@ def Packed : DiagGroup<"packed", [PackedNonPod]>;
def PaddedBitField : DiagGroup<"padded-bitfield">;
def Padded : DiagGroup<"padded", [PaddedBitField]>;
def UnalignedAccess : DiagGroup<"unaligned-access">;
-def SideEffectsUnavailable : DiagGroup<"side-effects-unavailable">;
def PessimizingMove : DiagGroup<"pessimizing-move">;
def ReturnStdMove : DiagGroup<"return-std-move">;
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index b61e064bc255bd..916fecefd01fd7 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -14496,11 +14496,20 @@ bool ASTContext::useAbbreviatedThunkName(GlobalDecl VirtualMethodDecl,
return Result;
}
+bool SemaProxy::getIgnoreSideEffectsOnAST() { return IgnoreSideEffectsOnAST; }
+
+void SemaProxy::setIgnoreSideEffectsOnAST(bool Ignore) {
+ IgnoreSideEffectsOnAST = Ignore;
+}
+
UnimplementedSemaProxy::UnimplementedSemaProxy(ASTContext &Ctx) : Ctx(Ctx) {}
void UnimplementedSemaProxy::InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function) {
- Ctx.getDiagnostics().Report(PointOfInstantiation,
- diag::warn_side_effects_on_ast_unavailable)
- << 0;
+ if (getIgnoreSideEffectsOnAST())
+ return;
+ llvm_unreachable(
+ "AST mutation was requested without clang::Sema available. "
+ "Consider providing it, or disabling side effects on AST via "
+ "ASTContext.getSemaProxy().setIgnoreSideEffectsOnAST(true).");
}
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 793e6ed3d059bd..f3568faba0b935 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -2814,6 +2814,8 @@ Attr *Sema::CreateAnnotationAttr(const ParsedAttr &AL) {
void SemaProxyImpl::InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function) {
+ if (getIgnoreSideEffectsOnAST())
+ return;
SemaRef.InstantiateFunctionDefinition(
PointOfInstantiation, Function, /*Recursive=*/true,
/*DefinitionRequired=*/true, /*AtEndOfTU=*/false);
>From 369aac84ae58a84e7feeacf5c4e982fbdfbd2571 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Fri, 15 Nov 2024 22:01:45 +0300
Subject: [PATCH 10/13] Mark both implementation of `SemaProxy` as `final`
---
clang/include/clang/AST/ASTContext.h | 2 +-
clang/include/clang/Sema/Sema.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index d7a9197500b30e..4b3d571b68489e 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -3611,7 +3611,7 @@ inline Selector GetUnarySelector(StringRef name, ASTContext &Ctx) {
}
/// Placeholder implementation that issues a diagnostic on any usage.
-struct UnimplementedSemaProxy : SemaProxy {
+struct UnimplementedSemaProxy final : SemaProxy {
ASTContext &Ctx;
explicit UnimplementedSemaProxy(ASTContext &);
virtual ~UnimplementedSemaProxy() = default;
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index dfde0e69323a65..b64ede7cf28196 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -355,7 +355,7 @@ struct SkipBodyInfo {
/// Implementation of SemaProxy interface that enables constant evaluator
/// to call Sema and modify AST, e.g. to instantiate templates.
-struct SemaProxyImpl : SemaProxy {
+struct SemaProxyImpl final : SemaProxy {
Sema &SemaRef;
explicit SemaProxyImpl(Sema &SemaRef);
void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
>From 0ffb6eea02f03521c753a41d83069472084a95c2 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Fri, 15 Nov 2024 22:10:42 +0300
Subject: [PATCH 11/13] Clean up `UnimplementedSemaProxy`
---
clang/include/clang/AST/ASTContext.h | 2 --
clang/lib/AST/ASTContext.cpp | 4 +---
2 files changed, 1 insertion(+), 5 deletions(-)
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index 4b3d571b68489e..d3cfb34b9c4ed9 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -3612,8 +3612,6 @@ inline Selector GetUnarySelector(StringRef name, ASTContext &Ctx) {
/// Placeholder implementation that issues a diagnostic on any usage.
struct UnimplementedSemaProxy final : SemaProxy {
- ASTContext &Ctx;
- explicit UnimplementedSemaProxy(ASTContext &);
virtual ~UnimplementedSemaProxy() = default;
void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 916fecefd01fd7..c02f3b5389dee5 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -904,7 +904,7 @@ ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
LangOpts.XRayAttrListFiles, SM)),
ProfList(new ProfileList(LangOpts.ProfileListFiles, SM)),
PrintingPolicy(LOpts),
- SemaProxyPtr(std::make_unique<UnimplementedSemaProxy>(*this)),
+ SemaProxyPtr(std::make_unique<UnimplementedSemaProxy>()),
Idents(idents), Selectors(sels), BuiltinInfo(builtins), TUKind(TUKind),
DeclarationNames(*this), Comments(SM),
CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
@@ -14502,8 +14502,6 @@ void SemaProxy::setIgnoreSideEffectsOnAST(bool Ignore) {
IgnoreSideEffectsOnAST = Ignore;
}
-UnimplementedSemaProxy::UnimplementedSemaProxy(ASTContext &Ctx) : Ctx(Ctx) {}
-
void UnimplementedSemaProxy::InstantiateFunctionDefinition(
SourceLocation PointOfInstantiation, FunctionDecl *Function) {
if (getIgnoreSideEffectsOnAST())
>From 857dc2f63c7aa2d6a1eb959fac3ca226566bfe3d Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Mon, 25 Nov 2024 21:06:09 +0300
Subject: [PATCH 12/13] Adjust the test case to acknowledge that it fails in
C++20
---
clang/lib/AST/ExprConstant.cpp | 3 ++-
.../SemaCXX/constexpr-function-instantiation.cpp | 16 ++++++++--------
2 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 4d523d9f15e9c4..4c6953f5933034 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -8329,7 +8329,8 @@ class ExprEvaluatorBase
const FunctionDecl *Definition = nullptr;
Stmt *Body = FD->getBody(Definition);
- if (!Definition && FD->getTemplateInstantiationPattern()) {
+ if (Info.getLangOpts().CPlusPlus23 && !Definition &&
+ FD->getTemplateInstantiationPattern()) {
Info.getSemaProxy().InstantiateFunctionDefinition(
E->getExprLoc(), const_cast<FunctionDecl *>(FD));
Body = FD->getBody(Definition);
diff --git a/clang/test/SemaCXX/constexpr-function-instantiation.cpp b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
index aec14e938be9f5..2480f14fdb7387 100644
--- a/clang/test/SemaCXX/constexpr-function-instantiation.cpp
+++ b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify=cxx20-23 %s
-// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=cxx20-23 %s
-// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=cxx26 %s
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify=cxx20 %s
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=cxx23-26 %s
+// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=cxx23-26 %s
-// cxx26-no-diagnostics
+// cxx23-26-no-diagnostics
namespace GH73232 {
namespace ex1 {
@@ -18,10 +18,10 @@ template <typename T>
constexpr void g(T) {}
constexpr auto z = f(); // #ex1-z-defn
-// cxx20-23-error at -1 {{constexpr variable 'z' must be initialized by a constant expression}}
-// cxx20-23-note@#ex1-g-call {{undefined function 'g<int>' cannot be used in a constant expression}}
-// cxx20-23-note@#ex1-z-defn {{in call to 'f()'}}
-// cxx20-23-note@#ex1-g-decl {{declared here}}
+// cxx20-error at -1 {{constexpr variable 'z' must be initialized by a constant expression}}
+// cxx20-note@#ex1-g-call {{undefined function 'g<int>' cannot be used in a constant expression}}
+// cxx20-note@#ex1-z-defn {{in call to 'f()'}}
+// cxx20-note@#ex1-g-decl {{declared here}}
} // namespace ex1
namespace ex2 {
>From 0b2d92e0fed41ee2428c3ef8b8369790a1279a21 Mon Sep 17 00:00:00 2001
From: Vlad Serebrennikov <serebrennikov.vladislav at gmail.com>
Date: Mon, 25 Nov 2024 21:47:41 +0300
Subject: [PATCH 13/13] Update the new constant interpreter to use the Sema
callback
---
clang/lib/AST/ByteCode/ByteCodeEmitter.cpp | 12 +++++++++++-
clang/lib/AST/ByteCode/ByteCodeEmitter.h | 2 +-
clang/lib/AST/ByteCode/Compiler.cpp | 9 +++++----
clang/lib/AST/ByteCode/Compiler.h | 2 +-
clang/lib/AST/ByteCode/Context.cpp | 8 +++++---
clang/lib/AST/ByteCode/Context.h | 3 ++-
.../SemaCXX/constexpr-function-instantiation.cpp | 4 ++++
7 files changed, 29 insertions(+), 11 deletions(-)
diff --git a/clang/lib/AST/ByteCode/ByteCodeEmitter.cpp b/clang/lib/AST/ByteCode/ByteCodeEmitter.cpp
index 4fd697ebe4938d..5b9fffdfc74dea 100644
--- a/clang/lib/AST/ByteCode/ByteCodeEmitter.cpp
+++ b/clang/lib/AST/ByteCode/ByteCodeEmitter.cpp
@@ -22,7 +22,8 @@
using namespace clang;
using namespace clang::interp;
-Function *ByteCodeEmitter::compileFunc(const FunctionDecl *FuncDecl) {
+Function *ByteCodeEmitter::compileFunc(const FunctionDecl *FuncDecl,
+ SourceLocation Loc) {
// Manually created functions that haven't been assigned proper
// parameters yet.
@@ -145,6 +146,15 @@ Function *ByteCodeEmitter::compileFunc(const FunctionDecl *FuncDecl) {
}
assert(Func);
+
+ if (Ctx.getLangOpts().CPlusPlus23 && !FuncDecl->isDefined() &&
+ FuncDecl->isImplicitlyInstantiable()) {
+ assert(Loc.isValid() && "Implicitly instantiating from the new constant "
+ "interpreter without a valid source location!");
+ Ctx.getASTContext().getSemaProxy().InstantiateFunctionDefinition(
+ Loc, const_cast<FunctionDecl *>(FuncDecl));
+ }
+
// For not-yet-defined functions, we only create a Function instance and
// compile their body later.
if (!FuncDecl->isDefined() ||
diff --git a/clang/lib/AST/ByteCode/ByteCodeEmitter.h b/clang/lib/AST/ByteCode/ByteCodeEmitter.h
index ac728830527a26..ac03a86aff41bd 100644
--- a/clang/lib/AST/ByteCode/ByteCodeEmitter.h
+++ b/clang/lib/AST/ByteCode/ByteCodeEmitter.h
@@ -31,7 +31,7 @@ class ByteCodeEmitter {
public:
/// Compiles the function into the module.
- Function *compileFunc(const FunctionDecl *FuncDecl);
+ Function *compileFunc(const FunctionDecl *FuncDecl, SourceLocation Loc);
Function *compileObjCBlock(const BlockExpr *BE);
protected:
diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp
index 59e09a44d747b9..734f122f3d10d4 100644
--- a/clang/lib/AST/ByteCode/Compiler.cpp
+++ b/clang/lib/AST/ByteCode/Compiler.cpp
@@ -2983,7 +2983,7 @@ bool Compiler<Emitter>::VisitCXXConstructExpr(const CXXConstructExpr *E) {
return true;
}
- const Function *Func = getFunction(Ctor);
+ const Function *Func = getFunction(Ctor, E->getExprLoc());
if (!Func)
return false;
@@ -4121,8 +4121,9 @@ Record *Compiler<Emitter>::getRecord(const RecordDecl *RD) {
}
template <class Emitter>
-const Function *Compiler<Emitter>::getFunction(const FunctionDecl *FD) {
- return Ctx.getOrCreateFunction(FD);
+const Function *Compiler<Emitter>::getFunction(const FunctionDecl *FD,
+ SourceLocation Loc) {
+ return Ctx.getOrCreateFunction(FD, Loc);
}
template <class Emitter>
@@ -4648,7 +4649,7 @@ bool Compiler<Emitter>::VisitCallExpr(const CallExpr *E) {
}
if (FuncDecl) {
- const Function *Func = getFunction(FuncDecl);
+ const Function *Func = getFunction(FuncDecl, E->getExprLoc());
if (!Func)
return false;
assert(HasRVO == Func->hasRVO());
diff --git a/clang/lib/AST/ByteCode/Compiler.h b/clang/lib/AST/ByteCode/Compiler.h
index 5627d5071e810a..c6f4b3b638765d 100644
--- a/clang/lib/AST/ByteCode/Compiler.h
+++ b/clang/lib/AST/ByteCode/Compiler.h
@@ -243,7 +243,7 @@ class Compiler : public ConstStmtVisitor<Compiler<Emitter>, bool>,
/// Returns a function for the given FunctionDecl.
/// If the function does not exist yet, it is compiled.
- const Function *getFunction(const FunctionDecl *FD);
+ const Function *getFunction(const FunctionDecl *FD, SourceLocation Loc = {});
std::optional<PrimType> classify(const Expr *E) const {
return Ctx.classify(E);
diff --git a/clang/lib/AST/ByteCode/Context.cpp b/clang/lib/AST/ByteCode/Context.cpp
index 7088cf02901c63..df34594242f4c3 100644
--- a/clang/lib/AST/ByteCode/Context.cpp
+++ b/clang/lib/AST/ByteCode/Context.cpp
@@ -29,7 +29,8 @@ bool Context::isPotentialConstantExpr(State &Parent, const FunctionDecl *FD) {
assert(Stk.empty());
Function *Func = P->getFunction(FD);
if (!Func || !Func->hasBody())
- Func = Compiler<ByteCodeEmitter>(*this, *P).compileFunc(FD);
+ Func =
+ Compiler<ByteCodeEmitter>(*this, *P).compileFunc(FD, SourceLocation{});
if (!Func)
return false;
@@ -270,7 +271,8 @@ Context::getOverridingFunction(const CXXRecordDecl *DynamicDecl,
return nullptr;
}
-const Function *Context::getOrCreateFunction(const FunctionDecl *FD) {
+const Function *Context::getOrCreateFunction(const FunctionDecl *FD,
+ SourceLocation Loc) {
assert(FD);
const Function *Func = P->getFunction(FD);
bool IsBeingCompiled = Func && Func->isDefined() && !Func->isFullyCompiled();
@@ -280,7 +282,7 @@ const Function *Context::getOrCreateFunction(const FunctionDecl *FD) {
return Func;
if (!Func || WasNotDefined) {
- if (auto F = Compiler<ByteCodeEmitter>(*this, *P).compileFunc(FD))
+ if (auto F = Compiler<ByteCodeEmitter>(*this, *P).compileFunc(FD, Loc))
Func = F;
}
diff --git a/clang/lib/AST/ByteCode/Context.h b/clang/lib/AST/ByteCode/Context.h
index e0d4bafdebaf2b..fd630dcaed708e 100644
--- a/clang/lib/AST/ByteCode/Context.h
+++ b/clang/lib/AST/ByteCode/Context.h
@@ -91,7 +91,8 @@ class Context final {
const CXXRecordDecl *StaticDecl,
const CXXMethodDecl *InitialFunction) const;
- const Function *getOrCreateFunction(const FunctionDecl *FD);
+ const Function *getOrCreateFunction(const FunctionDecl *FD,
+ SourceLocation Loc = {});
/// Returns whether we should create a global variable for the
/// given ValueDecl.
diff --git a/clang/test/SemaCXX/constexpr-function-instantiation.cpp b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
index 2480f14fdb7387..edc3e6fbd52639 100644
--- a/clang/test/SemaCXX/constexpr-function-instantiation.cpp
+++ b/clang/test/SemaCXX/constexpr-function-instantiation.cpp
@@ -2,6 +2,10 @@
// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=cxx23-26 %s
// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=cxx23-26 %s
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify=cxx20 -fexperimental-new-constant-interpreter %s
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=cxx23-26 -fexperimental-new-constant-interpreter %s
+// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=cxx23-26 -fexperimental-new-constant-interpreter %s
+
// cxx23-26-no-diagnostics
namespace GH73232 {
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