Revert "[clang] fixes named return of variables with dependent alignment"

This reverts commit 21106388eb.
It causes a segfault in certain cases.

clang/include/clang/AST/Decl.h

@@ -1494,9 +1494,6 @@ public:
     NonParmVarDeclBits.EscapingByref = true;
   }
 
-  /// Determines if this variable's alignment is dependent.
-  bool hasDependentAlignment() const;
-
   /// Retrieve the variable declaration from which this variable could
   /// be instantiated, if it is an instantiation (rather than a non-template).
   VarDecl *getTemplateInstantiationPattern() const;

clang/lib/AST/Decl.cpp

@@ -2534,13 +2534,6 @@ bool VarDecl::isNonEscapingByref() const {
   return hasAttr<BlocksAttr>() && !NonParmVarDeclBits.EscapingByref;
 }
 
-bool VarDecl::hasDependentAlignment() const {
-  return getType()->isDependentType() ||
-         llvm::any_of(specific_attrs<AlignedAttr>(), [](const AlignedAttr *AA) {
-           return AA->isAlignmentDependent();
-         });
-}
-
 VarDecl *VarDecl::getTemplateInstantiationPattern() const {
   const VarDecl *VD = this;
 

clang/lib/Sema/SemaDecl.cpp

@@ -13310,6 +13310,16 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
     CheckCompleteDecompositionDeclaration(DD);
 }
 
+/// Determines if a variable's alignment is dependent.
+static bool hasDependentAlignment(VarDecl *VD) {
+  if (VD->getType()->isDependentType())
+    return true;
+  for (auto *I : VD->specific_attrs<AlignedAttr>())
+    if (I->isAlignmentDependent())
+      return true;
+  return false;
+}
+
 /// Check if VD needs to be dllexport/dllimport due to being in a
 /// dllexport/import function.
 void Sema::CheckStaticLocalForDllExport(VarDecl *VD) {
@@ -13398,7 +13408,7 @@ void Sema::FinalizeDeclaration(Decl *ThisDecl) {
   if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
     // Protect the check so that it's not performed on dependent types and
     // dependent alignments (we can't determine the alignment in that case).
-    if (VD->getTLSKind() && !VD->hasDependentAlignment() &&
+    if (VD->getTLSKind() && !hasDependentAlignment(VD) &&
         !VD->isInvalidDecl()) {
       CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
       if (Context.getDeclAlign(VD) > MaxAlignChars) {

clang/lib/Sema/SemaStmt.cpp

@@ -3395,7 +3395,7 @@ Sema::NamedReturnInfo Sema::getNamedReturnInfo(const VarDecl *VD) {
 
   // Variables with higher required alignment than their type's ABI
   // alignment cannot use NRVO.
-  if (!VD->hasDependentAlignment() &&
+  if (!VDType->isDependentType() && VD->hasAttr<AlignedAttr>() &&
       Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VDType))
     Info.S = NamedReturnInfo::MoveEligible;
 

clang/test/CodeGen/nrvo-tracking.cpp

@@ -1,6 +1,6 @@
 // RUN: %clang_cc1 -std=c++20 -fblocks -Wno-return-stack-address -triple x86_64-unknown-unknown-gnu -emit-llvm -O1 -fexperimental-new-pass-manager -o - %s | FileCheck %s
 
-struct alignas(4) X {
+struct X {
     X();
     X(const X&);
     X(X&&);
@@ -210,75 +210,3 @@ void b_attr() {
     };
   }()();
 }
-
-namespace test_alignas {
-
-template <int A> X t1() {
-  X a [[gnu::aligned(A)]];
-  return a;
-}
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t1ILi1EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  ret void
-template X t1<1>();
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t1ILi4EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  ret void
-template X t1<4>();
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t1ILi8EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  call {{.*}} @_ZN1XC1EOS_
-// CHECK-NEXT:  call void @llvm.lifetime.end
-template X t1<8>();
-
-template <int A> X t2() {
-  X a [[gnu::aligned(1)]] [[gnu::aligned(A)]] [[gnu::aligned(2)]];
-  return a;
-}
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t2ILi1EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  ret void
-template X t2<1>();
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t2ILi4EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  ret void
-template X t2<4>();
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t2ILi8EEE1Xv
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  call {{.*}} @_ZN1XC1EOS_
-// CHECK-NEXT:  call void @llvm.lifetime.end
-template X t2<8>();
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t3Ev
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  ret void
-X t3() {
-  X a [[gnu::aligned(1)]];
-  return a;
-}
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t4Ev
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  call {{.*}} @_ZN1XC1EOS_
-// CHECK-NEXT:  call void @llvm.lifetime.end
-X t4() {
-  X a [[gnu::aligned(8)]];
-  return a;
-}
-
-// CHECK-LABEL: define{{.*}} void @_ZN12test_alignas2t5Ev
-// CHECK:       call {{.*}} @_ZN1XC1Ev
-// CHECK-NEXT:  call {{.*}} @_ZN1XC1EOS_
-// CHECK-NEXT:  call void @llvm.lifetime.end
-X t5() {
-  X a [[gnu::aligned(1)]] [[gnu::aligned(8)]];
-  return a;
-}
-
-} // namespace test_alignas