https://github.com/Sirraide created
https://github.com/llvm/llvm-project/pull/83187
When resolving the type of `this` inside a member function, we were attaching
all qualifiers present on the member function to the class type and then making
it a pointer; however, `__restrict`, unlike `const` and `volatile`, needs to be
attached to the pointer type rather than the pointee type.
This fixes #82941.
>From e9df22166fd5768e11273446cb9e52953e55cd5d Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalm...@gmail.com>
Date: Tue, 27 Feb 2024 22:07:23 +0100
Subject: [PATCH 1/3] [Clang] [Sema] Handle __restrict-qualified member
functions properly
---
clang/lib/AST/DeclCXX.cpp | 15 ++++++--
clang/lib/Sema/SemaExprCXX.cpp | 2 +-
clang/test/SemaCXX/restrict-this.cpp | 51 ++++++++++++++++++++++++++++
3 files changed, 65 insertions(+), 3 deletions(-)
create mode 100644 clang/test/SemaCXX/restrict-this.cpp
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 117e802dae2d9d..b4f2327d9c560a 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -2543,8 +2543,19 @@ QualType CXXMethodDecl::getThisType(const
FunctionProtoType *FPT,
const CXXRecordDecl *Decl) {
ASTContext &C = Decl->getASTContext();
QualType ObjectTy = ::getThisObjectType(C, FPT, Decl);
- return C.getLangOpts().HLSL ? C.getLValueReferenceType(ObjectTy)
- : C.getPointerType(ObjectTy);
+
+ // Unlike 'const' and 'volatile', a '__restrict' qualifier must be
+ // attached to the pointer type, not the pointee.
+ bool Restrict = FPT->getMethodQuals().hasRestrict();
+ if (Restrict)
+ ObjectTy.removeLocalRestrict();
+
+ ObjectTy = C.getLangOpts().HLSL ? C.getLValueReferenceType(ObjectTy)
+ : C.getPointerType(ObjectTy);
+
+ if (Restrict)
+ ObjectTy.addRestrict();
+ return ObjectTy;
}
QualType CXXMethodDecl::getThisType() const {
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 59758d3bd6d1a3..c4750ce78fa9c1 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -1220,7 +1220,7 @@ static QualType adjustCVQualifiersForCXXThisWithinLambda(
: nullptr;
}
}
- return ASTCtx.getPointerType(ClassType);
+ return ThisTy;
}
QualType Sema::getCurrentThisType() {
diff --git a/clang/test/SemaCXX/restrict-this.cpp
b/clang/test/SemaCXX/restrict-this.cpp
new file mode 100644
index 00000000000000..79c6081f904275
--- /dev/null
+++ b/clang/test/SemaCXX/restrict-this.cpp
@@ -0,0 +1,51 @@
+// RUN: %clang_cc1 -verify -fsyntax-only %s
+// expected-no-diagnostics
+
+struct C {
+ void f() __restrict {
+ static_assert(__is_same(decltype(this), C *__restrict));
+ (void) [this]() {
+ static_assert(__is_same(decltype(this), C *__restrict));
+ (void) [this]() { static_assert(__is_same(decltype(this), C
*__restrict)); };
+
+ // By-value capture means 'this' is now a different object; do not
+ // make it __restrict.
+ (void) [*this]() { static_assert(__is_same(decltype(this), const C *));
};
+ (void) [*this]() mutable { static_assert(__is_same(decltype(this), C
*)); };
+ };
+ }
+};
+
+template <typename T> struct TC {
+ void f() __restrict {
+ static_assert(__is_same(decltype(this), TC<int> *__restrict));
+ (void) [this]() {
+ static_assert(__is_same(decltype(this), TC<int> *__restrict));
+ (void) [this]() { static_assert(__is_same(decltype(this), TC<int>
*__restrict)); };
+
+ // By-value capture means 'this' is now a different object; do not
+ // make it __restrict.
+ (void) [*this]() { static_assert(__is_same(decltype(this), const TC<int>
*)); };
+ (void) [*this]() mutable { static_assert(__is_same(decltype(this),
TC<int> *)); };
+ };
+ }
+};
+
+void f() {
+ TC<int>{}.f();
+}
+
+namespace gh82941 {
+void f(int& x) {
+ (void)x;
+}
+
+class C {
+ int x;
+ void g() __restrict;
+};
+
+void C::g() __restrict {
+ f(this->x);
+}
+}
\ No newline at end of file
>From c3031a9699582391e25e1bccd58fad59fbec379b Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalm...@gmail.com>
Date: Tue, 27 Feb 2024 22:13:09 +0100
Subject: [PATCH 2/3] [Clang] Update release notes
---
clang/docs/ReleaseNotes.rst | 3 +++
1 file changed, 3 insertions(+)
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 7e16b9f0c67dbd..d420f572a84487 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -290,6 +290,9 @@ Bug Fixes to C++ Support
lookup searches the bases of an incomplete class.
- Fix a crash when an unresolved overload set is encountered on the RHS of a
``.*`` operator.
(`#53815 <https://github.com/llvm/llvm-project/issues/53815>`_)
+- In ``__restrict``-qualified member functions, attach ``__restrict`` to the
pointer type of
+ ``this`` rather than the pointee type.
+ Fixes (`#82941 <https://github.com/llvm/llvm-project/issues/82941>`_).
Bug Fixes to AST Handling
^^^^^^^^^^^^^^^^^^^^^^^^^
>From 073be09acf2b20bc20b15615c81b5ae89e490786 Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalm...@gmail.com>
Date: Tue, 27 Feb 2024 22:16:43 +0100
Subject: [PATCH 3/3] [NFC] Add newline at end of file
---
clang/test/SemaCXX/restrict-this.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/clang/test/SemaCXX/restrict-this.cpp
b/clang/test/SemaCXX/restrict-this.cpp
index 79c6081f904275..8cd89f0f36a76c 100644
--- a/clang/test/SemaCXX/restrict-this.cpp
+++ b/clang/test/SemaCXX/restrict-this.cpp
@@ -48,4 +48,4 @@ class C {
void C::g() __restrict {
f(this->x);
}
-}
\ No newline at end of file
+}
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
