[clang] 3a03513 - Revert "[clang] Introduce [[clang::lifetime_capture_by(X)]] (#111499)"
Nikita Popov via cfe-commits
cfe-commits at lists.llvm.org
Mon Nov 11 11:57:36 PST 2024
Author: Nikita Popov
Date: 2024-11-11T20:57:26+01:00
New Revision: 3a03513fc6ef8f3272d33be19164243c9dbf0452
URL: https://github.com/llvm/llvm-project/commit/3a03513fc6ef8f3272d33be19164243c9dbf0452
DIFF: https://github.com/llvm/llvm-project/commit/3a03513fc6ef8f3272d33be19164243c9dbf0452.diff
LOG: Revert "[clang] Introduce [[clang::lifetime_capture_by(X)]] (#111499)"
This reverts commit 8c4331c1abeb33eabf3cdbefa7f2b6e0540e7f4f.
Causes a large compile-time regression, see:
https://llvm-compile-time-tracker.com/compare.php?from=4a68e4cbd2423dcacada8162ab7c4bb8d7f7e2cf&to=8c4331c1abeb33eabf3cdbefa7f2b6e0540e7f4f&stat=instructions:u
Added:
Modified:
clang/docs/ReleaseNotes.rst
clang/include/clang/Basic/Attr.td
clang/include/clang/Basic/AttrDocs.td
clang/include/clang/Basic/DiagnosticSemaKinds.td
clang/include/clang/Sema/Sema.h
clang/lib/AST/TypePrinter.cpp
clang/lib/Sema/SemaDecl.cpp
clang/lib/Sema/SemaDeclAttr.cpp
clang/lib/Sema/SemaType.cpp
Removed:
clang/test/AST/attr-lifetime-capture-by.cpp
clang/test/SemaCXX/attr-lifetime-capture-by.cpp
################################################################################
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index e817b0ceb3fd06..e235a04f78112b 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -449,9 +449,6 @@ Attribute Changes in Clang
- Fix a bug where clang doesn't automatically apply the ``[[gsl::Owner]]`` or
``[[gsl::Pointer]]`` to STL explicit template specialization decls. (#GH109442)
-- Clang now supports ``[[clang::lifetime_capture_by(X)]]``. Similar to lifetimebound, this can be
- used to specify when a reference to a function parameter is captured by another capturing entity ``X``.
-
Improvements to Clang's diagnostics
-----------------------------------
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index 6a77967c32cbcb..a631e81d40aa68 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -1889,39 +1889,6 @@ def LifetimeBound : DeclOrTypeAttr {
let SimpleHandler = 1;
}
-def LifetimeCaptureBy : DeclOrTypeAttr {
- let Spellings = [Clang<"lifetime_capture_by", 0>];
- let Subjects = SubjectList<[ParmVar, ImplicitObjectParameter], ErrorDiag>;
- let Args = [VariadicParamOrParamIdxArgument<"Params">];
- let Documentation = [LifetimeCaptureByDocs];
- let AdditionalMembers = [{
-private:
- SmallVector<IdentifierInfo*, 1> ArgIdents;
- SmallVector<SourceLocation, 1> ArgLocs;
-
-public:
- static constexpr int THIS = 0;
- static constexpr int INVALID = -1;
- static constexpr int UNKNOWN = -2;
- static constexpr int GLOBAL = -3;
-
- void setArgs(SmallVector<IdentifierInfo*>&& Idents,
- SmallVector<SourceLocation>&& Locs) {
- assert(Idents.size() == Locs.size());
- assert(Idents.size() == params_Size);
- ArgIdents = std::move(Idents);
- ArgLocs = std::move(Locs);
- }
-
- ArrayRef<IdentifierInfo*> getArgIdents() const { return ArgIdents; }
- ArrayRef<SourceLocation> getArgLocs() const { return ArgLocs; }
- void setParamIdx(size_t Idx, int Val) {
- assert(Idx < params_Size);
- params_[Idx] = Val;
- }
-}];
-}
-
def TrivialABI : InheritableAttr {
// This attribute does not have a C [[]] spelling because it requires the
// CPlusPlus language option.
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index 21fcd183e8969c..b64dbef6332e6a 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -3918,75 +3918,6 @@ have their lifetimes extended.
}];
}
-def LifetimeCaptureByDocs : Documentation {
- let Category = DocCatFunction;
- let Content = [{
- Similar to `lifetimebound`_, the ``lifetime_capture_by(X)`` attribute on a function
-parameter or implicit object parameter indicates that that objects that are referred to
-by that parameter may also be referred to by the capturing entity ``X``.
-
-By default, a reference is considered to refer to its referenced object, a
-pointer is considered to refer to its pointee, a ``std::initializer_list<T>``
-is considered to refer to its underlying array, and aggregates (arrays and
-simple ``struct``\s) are considered to refer to all objects that their
-transitive subobjects refer to.
-
-The capturing entity ``X`` can be one of the following:
-- Another (named) function parameter.
-
- .. code-block:: c++
-
- void addToSet(std::string_view a [[clang::lifetime_capture_by(s)]], std::set<std::string_view>& s) {
- s.insert(a);
- }
-
-- ``this`` (in case of member functions).
-
- .. code-block:: c++
-
- class S {
- void addToSet(std::string_view a [[clang::lifetime_capture_by(this)]]) {
- s.insert(a);
- }
- std::set<std::string_view> s;
- };
-
-- 'global', 'unknown' (without quotes).
-
- .. code-block:: c++
-
- std::set<std::string_view> s;
- void addToSet(std::string_view a [[clang::lifetime_capture_by(global)]]) {
- s.insert(a);
- }
- void addSomewhere(std::string_view a [[clang::lifetime_capture_by(unknown)]]);
-
-The attribute can be applied to the implicit ``this`` parameter of a member
-function by writing the attribute after the function type:
-
-.. code-block:: c++
-
- struct S {
- const char *data(std::set<S*>& s) [[clang::lifetime_capture_by(s)]] {
- s.insert(this);
- }
- };
-
-The attribute supports specifying more than one capturing entities:
-
-.. code-block:: c++
-
- void addToSets(std::string_view a [[clang::lifetime_capture_by(s1, s2)]],
- std::set<std::string_view>& s1,
- std::set<std::string_view>& s2) {
- s1.insert(a);
- s2.insert(a);
- }
-
-.. _`lifetimebound`: https://clang.llvm.org/docs/AttributeReference.html#lifetimebound
- }];
-}
-
def TrivialABIDocs : Documentation {
let Category = DocCatDecl;
let Content = [{
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index f4452fbb57e736..a5d97d7e545ffd 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3383,20 +3383,6 @@ def err_callback_callee_is_variadic : Error<
"'callback' attribute callee may not be variadic">;
def err_callback_implicit_this_not_available : Error<
"'callback' argument at position %0 references unavailable implicit 'this'">;
-
-def err_capture_by_attribute_multiple : Error<
- "multiple 'lifetime_capture' attributes specified">;
-def err_capture_by_attribute_no_entity : Error<
- "'lifetime_capture_by' attribute specifies no capturing entity">;
-def err_capture_by_implicit_this_not_available : Error<
- "'lifetime_capture_by' argument references unavailable implicit 'this'">;
-def err_capture_by_attribute_argument_unknown : Error<
- "'lifetime_capture_by' attribute argument %0 is not a known function parameter"
- "; must be a function parameter, 'this', 'global' or 'unknown'">;
-def err_capture_by_references_itself : Error<"'lifetime_capture_by' argument references itself">;
-def err_capture_by_param_uses_reserved_name : Error<
- "parameter cannot be named '%select{global|unknown}0' while using 'lifetime_capture_by(%select{global|unknown}0)'">;
-
def err_init_method_bad_return_type : Error<
"init methods must return an object pointer type, not %0">;
def err_attribute_invalid_size : Error<
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index d6f3508a5243f3..fad446a05e782f 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -1760,14 +1760,6 @@ class Sema final : public SemaBase {
/// Add [[gsl::Pointer]] attributes for std:: types.
void inferGslPointerAttribute(TypedefNameDecl *TD);
- LifetimeCaptureByAttr *ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
- StringRef ParamName);
- // Processes the argument 'X' in [[clang::lifetime_capture_by(X)]]. Since 'X'
- // can be the name of a function parameter, we need to parse the function
- // declaration and rest of the parameters before processesing 'X'. Therefore
- // do this lazily instead of processing while parsing the annotation itself.
- void LazyProcessLifetimeCaptureByParams(FunctionDecl *FD);
-
/// Add _Nullable attributes for std:: types.
void inferNullableClassAttribute(CXXRecordDecl *CRD);
diff --git a/clang/lib/AST/TypePrinter.cpp b/clang/lib/AST/TypePrinter.cpp
index a073a6a4b7d454..6d8db5cf4ffd22 100644
--- a/clang/lib/AST/TypePrinter.cpp
+++ b/clang/lib/AST/TypePrinter.cpp
@@ -25,7 +25,6 @@
#include "clang/AST/TextNodeDumper.h"
#include "clang/AST/Type.h"
#include "clang/Basic/AddressSpaces.h"
-#include "clang/Basic/AttrKinds.h"
#include "clang/Basic/ExceptionSpecificationType.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/LLVM.h"
@@ -1910,19 +1909,6 @@ void TypePrinter::printAttributedAfter(const AttributedType *T,
OS << " [[clang::lifetimebound]]";
return;
}
- if (T->getAttrKind() == attr::LifetimeCaptureBy) {
- OS << " [[clang::lifetime_capture_by(";
- if (auto *attr = dyn_cast_or_null<LifetimeCaptureByAttr>(T->getAttr())) {
- auto Idents = attr->getArgIdents();
- for (unsigned I = 0; I < Idents.size(); ++I) {
- OS << Idents[I]->getName();
- if (I != Idents.size() - 1)
- OS << ", ";
- }
- }
- OS << ")]]";
- return;
- }
// The printing of the address_space attribute is handled by the qualifier
// since it is still stored in the qualifier. Return early to prevent printing
@@ -1990,7 +1976,6 @@ void TypePrinter::printAttributedAfter(const AttributedType *T,
case attr::SizedBy:
case attr::SizedByOrNull:
case attr::LifetimeBound:
- case attr::LifetimeCaptureBy:
case attr::TypeNonNull:
case attr::TypeNullable:
case attr::TypeNullableResult:
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index a3bc8e4191c819..61c29e320d5c73 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -16687,7 +16687,6 @@ void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
}
}
- LazyProcessLifetimeCaptureByParams(FD);
inferLifetimeBoundAttribute(FD);
AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction(FD);
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index b4aaa58c082002..d05d326178e1b8 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -14,7 +14,6 @@
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTMutationListener.h"
#include "clang/AST/CXXInheritance.h"
-#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
@@ -3868,113 +3867,6 @@ static void handleCallbackAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
S.Context, AL, EncodingIndices.data(), EncodingIndices.size()));
}
-LifetimeCaptureByAttr *Sema::ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
- StringRef ParamName) {
- // Atleast one capture by is required.
- if (AL.getNumArgs() == 0) {
- Diag(AL.getLoc(), diag::err_capture_by_attribute_no_entity)
- << AL.getRange();
- return nullptr;
- }
- SmallVector<IdentifierInfo *, 1> ParamIdents;
- SmallVector<SourceLocation, 1> ParamLocs;
- for (unsigned I = 0; I < AL.getNumArgs(); ++I) {
- if (AL.isArgExpr(I)) {
- Expr *E = AL.getArgAsExpr(I);
- Diag(E->getExprLoc(), diag::err_capture_by_attribute_argument_unknown)
- << E << E->getExprLoc();
- continue;
- }
- assert(AL.isArgIdent(I));
- IdentifierLoc *IdLoc = AL.getArgAsIdent(I);
- if (IdLoc->Ident->getName() == ParamName) {
- Diag(IdLoc->Loc, diag::err_capture_by_references_itself) << IdLoc->Loc;
- continue;
- }
- ParamIdents.push_back(IdLoc->Ident);
- ParamLocs.push_back(IdLoc->Loc);
- }
- SmallVector<int, 1> FakeParamIndices(ParamIdents.size(),
- LifetimeCaptureByAttr::INVALID);
- LifetimeCaptureByAttr *CapturedBy = ::new (Context) LifetimeCaptureByAttr(
- Context, AL, FakeParamIndices.data(), FakeParamIndices.size());
- CapturedBy->setArgs(std::move(ParamIdents), std::move(ParamLocs));
- return CapturedBy;
-}
-
-static void HandleLifetimeCaptureByAttr(Sema &S, Decl *D,
- const ParsedAttr &AL) {
- // Do not allow multiple attributes.
- if (D->hasAttr<LifetimeCaptureByAttr>()) {
- S.Diag(AL.getLoc(), diag::err_capture_by_attribute_multiple)
- << AL.getRange();
- return;
- }
- auto *PVD = dyn_cast<ParmVarDecl>(D);
- assert(PVD);
- auto *CaptureByAttr = S.ParseLifetimeCaptureByAttr(AL, PVD->getName());
- if (CaptureByAttr)
- D->addAttr(CaptureByAttr);
-}
-
-void Sema::LazyProcessLifetimeCaptureByParams(FunctionDecl *FD) {
- bool HasImplicitThisParam = isInstanceMethod(FD);
-
- llvm::StringMap<int> NameIdxMapping;
- NameIdxMapping["global"] = LifetimeCaptureByAttr::GLOBAL;
- NameIdxMapping["unknown"] = LifetimeCaptureByAttr::UNKNOWN;
- int Idx = 0;
- if (HasImplicitThisParam) {
- NameIdxMapping["this"] = 0;
- Idx++;
- }
- for (const ParmVarDecl *PVD : FD->parameters())
- NameIdxMapping[PVD->getName()] = Idx++;
- auto DisallowReservedParams = [&](StringRef Reserved) {
- for (const ParmVarDecl *PVD : FD->parameters())
- if (PVD->getName() == Reserved)
- Diag(PVD->getLocation(), diag::err_capture_by_param_uses_reserved_name)
- << (PVD->getName() == "unknown");
- };
- auto HandleCaptureBy = [&](LifetimeCaptureByAttr *CapturedBy) {
- if (!CapturedBy)
- return;
- const auto &Entities = CapturedBy->getArgIdents();
- for (size_t I = 0; I < Entities.size(); ++I) {
- StringRef Name = Entities[I]->getName();
- auto It = NameIdxMapping.find(Name);
- if (It == NameIdxMapping.end()) {
- auto Loc = CapturedBy->getArgLocs()[I];
- if (!HasImplicitThisParam && Name == "this")
- Diag(Loc, diag::err_capture_by_implicit_this_not_available) << Loc;
- else
- Diag(Loc, diag::err_capture_by_attribute_argument_unknown)
- << Entities[I] << Loc;
- continue;
- }
- if (Name == "unknown" || Name == "global")
- DisallowReservedParams(Name);
- CapturedBy->setParamIdx(I, It->second);
- }
- };
- for (ParmVarDecl *PVD : FD->parameters())
- HandleCaptureBy(PVD->getAttr<LifetimeCaptureByAttr>());
- if (!HasImplicitThisParam)
- return;
- TypeSourceInfo *TSI = FD->getTypeSourceInfo();
- if (!TSI)
- return;
- AttributedTypeLoc ATL;
- for (TypeLoc TL = TSI->getTypeLoc();
- (ATL = TL.getAsAdjusted<AttributedTypeLoc>());
- TL = ATL.getModifiedLoc()) {
- auto *A = ATL.getAttrAs<LifetimeCaptureByAttr>();
- if (!A)
- continue;
- HandleCaptureBy(const_cast<LifetimeCaptureByAttr *>(A));
- }
-}
-
static bool isFunctionLike(const Type &T) {
// Check for explicit function types.
// 'called_once' is only supported in Objective-C and it has
@@ -6752,9 +6644,6 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
case ParsedAttr::AT_Callback:
handleCallbackAttr(S, D, AL);
break;
- case ParsedAttr::AT_LifetimeCaptureBy:
- HandleLifetimeCaptureByAttr(S, D, AL);
- break;
case ParsedAttr::AT_CalledOnce:
handleCalledOnceAttr(S, D, AL);
break;
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index eb7516b3ef1ece..515b9f689a248a 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -8609,15 +8609,6 @@ static void HandleLifetimeBoundAttr(TypeProcessingState &State,
}
}
-static void HandleLifetimeCaptureByAttr(TypeProcessingState &State,
- QualType &CurType, ParsedAttr &PA) {
- if (State.getDeclarator().isDeclarationOfFunction()) {
- auto *Attr = State.getSema().ParseLifetimeCaptureByAttr(PA, "this");
- if (Attr)
- CurType = State.getAttributedType(Attr, CurType, CurType);
- }
-}
-
static void HandleHLSLParamModifierAttr(TypeProcessingState &State,
QualType &CurType,
const ParsedAttr &Attr, Sema &S) {
@@ -8779,10 +8770,6 @@ static void processTypeAttrs(TypeProcessingState &state, QualType &type,
if (TAL == TAL_DeclChunk)
HandleLifetimeBoundAttr(state, type, attr);
break;
- case ParsedAttr::AT_LifetimeCaptureBy:
- if (TAL == TAL_DeclChunk)
- HandleLifetimeCaptureByAttr(state, type, attr);
- break;
case ParsedAttr::AT_NoDeref: {
// FIXME: `noderef` currently doesn't work correctly in [[]] syntax.
diff --git a/clang/test/AST/attr-lifetime-capture-by.cpp b/clang/test/AST/attr-lifetime-capture-by.cpp
deleted file mode 100644
index da2eb0cf3d592e..00000000000000
--- a/clang/test/AST/attr-lifetime-capture-by.cpp
+++ /dev/null
@@ -1,9 +0,0 @@
-// RUN: %clang_cc1 %s -ast-dump | FileCheck %s
-
-// Verify that we print the [[clang::lifetime_capture_by(X)]] attribute.
-
-struct S {
- void foo(int &a, int &b) [[clang::lifetime_capture_by(a, b, global)]];
-};
-
-// CHECK: CXXMethodDecl {{.*}}clang::lifetime_capture_by(a, b, global)
diff --git a/clang/test/SemaCXX/attr-lifetime-capture-by.cpp b/clang/test/SemaCXX/attr-lifetime-capture-by.cpp
deleted file mode 100644
index 3115dc8d6150c9..00000000000000
--- a/clang/test/SemaCXX/attr-lifetime-capture-by.cpp
+++ /dev/null
@@ -1,46 +0,0 @@
-// RUN: %clang_cc1 -std=c++23 -verify %s
-
-struct S {
- const int *x;
- void captureInt(const int&x [[clang::lifetime_capture_by(this)]]) { this->x = &x; }
-};
-
-///////////////////////////
-// Test for valid usages.
-///////////////////////////
-[[clang::lifetime_capture_by(unknown)]] // expected-error {{'lifetime_capture_by' attribute only applies to parameters and implicit object parameters}}
-void nonMember(
- const int &x1 [[clang::lifetime_capture_by(s, t)]],
- S &s,
- S &t,
- const int &x2 [[clang::lifetime_capture_by(12345 + 12)]], // expected-error {{'lifetime_capture_by' attribute argument 12345 + 12 is not a known function parameter; must be a function parameter, 'this', 'global' or 'unknown'}}
- const int &x3 [[clang::lifetime_capture_by(abcdefgh)]], // expected-error {{'lifetime_capture_by' attribute argument 'abcdefgh' is not a known function parameter; must be a function parameter, 'this', 'global' or 'unknown'}}
- const int &x4 [[clang::lifetime_capture_by("abcdefgh")]], // expected-error {{'lifetime_capture_by' attribute argument "abcdefgh" is not a known function parameter; must be a function parameter, 'this', 'global' or 'unknown'}}
- const int &x5 [[clang::lifetime_capture_by(this)]], // expected-error {{'lifetime_capture_by' argument references unavailable implicit 'this'}}
- const int &x6 [[clang::lifetime_capture_by()]], // expected-error {{'lifetime_capture_by' attribute specifies no capturing entity}}
- const int& x7 [[clang::lifetime_capture_by(u,
- x7)]], // expected-error {{'lifetime_capture_by' argument references itself}}
- const int &x8 [[clang::lifetime_capture_by(global)]],
- const int &x9 [[clang::lifetime_capture_by(unknown)]],
- const S& u
- )
-{
- s.captureInt(x1);
-}
-
-void unknown_param_name(const int& unknown, // expected-error {{parameter cannot be named 'unknown' while using 'lifetime_capture_by(unknown)'}}
- const int& s [[clang::lifetime_capture_by(unknown)]]);
-void global_param_name(const int& global, // expected-error {{parameter cannot be named 'global' while using 'lifetime_capture_by(global)'}}
- const int& s [[clang::lifetime_capture_by(global)]]);
-struct T {
- void member(
- const int &x [[clang::lifetime_capture_by(s)]],
- S &s,
- S &t,
- const int &y [[clang::lifetime_capture_by(s)]],
- const int &z [[clang::lifetime_capture_by(this, x, y)]],
- const int &u [[clang::lifetime_capture_by(global, unknown, x, s)]])
- {
- s.captureInt(x);
- }
-};
More information about the cfe-commits
mailing list