diff --git a/clang/lib/Sema/SemaSYCLDeclAttr.cpp b/clang/lib/Sema/SemaSYCLDeclAttr.cpp
index 58ee6e81534be..22b72b89133d5 100644
--- a/clang/lib/Sema/SemaSYCLDeclAttr.cpp
+++ b/clang/lib/Sema/SemaSYCLDeclAttr.cpp
@@ -1537,6 +1537,20 @@ void SemaSYCL::addSYCLAddIRAttributesFunctionAttr(
   if (evaluateAddIRAttributesArgs(Attr->args_begin(), Attr->args_size(), *this,
                                   CI))
     return;
+
+  // There could be multiple of the same attribute applied to the same
+  // declaration. If so, we want to merge them.
+  // If there are still dependent expressions in the attribute, we delay merging
+  // till after instantiation.
+  if (!hasDependentExpr(Attr->args_begin(), Attr->args_size()) &&
+      D->hasAttr<SYCLAddIRAttributesFunctionAttr>()) {
+    Attr = mergeSYCLAddIRAttributesFunctionAttr(D, *Attr);
+
+    // If null is returned, the attribute did not change after merge and we can
+    // exit.
+    if (!Attr)
+      return;
+  }
   D->addAttr(Attr);
 
   // There are compile-time SYCL properties which we would like to turn into
@@ -1574,6 +1588,20 @@ void SemaSYCL::addSYCLAddIRAttributesKernelParameterAttr(
   if (evaluateAddIRAttributesArgs(Attr->args_begin(), Attr->args_size(), *this,
                                   CI))
     return;
+
+  // There could be multiple of the same attribute applied to the same argument.
+  // If so, we want to merge them.
+  // If there are still dependent expressions in the attribute, we delay merging
+  // till after instantiation.
+  if (!hasDependentExpr(Attr->args_begin(), Attr->args_size()) &&
+      D->hasAttr<SYCLAddIRAttributesKernelParameterAttr>()) {
+    Attr = mergeSYCLAddIRAttributesKernelParameterAttr(D, *Attr);
+
+    // If null is returned, the attribute did not change after merge and we can
+    // exit.
+    if (!Attr)
+      return;
+  }
   D->addAttr(Attr);
 }
 
@@ -1585,6 +1613,20 @@ void SemaSYCL::addSYCLAddIRAttributesGlobalVariableAttr(
   if (evaluateAddIRAttributesArgs(Attr->args_begin(), Attr->args_size(), *this,
                                   CI))
     return;
+
+  // There could be multiple of the same attribute applied to the same global
+  // variable. If so, we want to merge them.
+  // If there are still dependent expressions in the attribute, we delay merging
+  // till after instantiation.
+  if (!hasDependentExpr(Attr->args_begin(), Attr->args_size()) &&
+      D->hasAttr<SYCLAddIRAttributesGlobalVariableAttr>()) {
+    Attr = mergeSYCLAddIRAttributesGlobalVariableAttr(D, *Attr);
+
+    // If null is returned, the attribute did not change after merge and we can
+    // exit.
+    if (!Attr)
+      return;
+  }
   D->addAttr(Attr);
 }
 
@@ -2559,14 +2601,19 @@ void SemaSYCL::handleSYCLAddIRAttributesFunctionAttr(Decl *D,
   addSYCLAddIRAttributesFunctionAttr(D, A, Args);
 }
 
-static bool hasSameSYCLAddIRAttributes(
+static bool hasConflictingSYCLAddIRAttributes(
     const SmallVector<std::pair<std::string, std::string>, 4> &LAttrs,
     const SmallVector<std::pair<std::string, std::string>, 4> &RAttrs) {
-  std::set<std::pair<std::string, std::string>> LNameValSet{LAttrs.begin(),
-                                                            LAttrs.end()};
-  std::set<std::pair<std::string, std::string>> RNameValSet{RAttrs.begin(),
-                                                            RAttrs.end()};
-  return LNameValSet == RNameValSet;
+  std::unordered_map<std::string, std::string> LNameValMap;
+  for (const std::pair<std::string, std::string> &NameValuePair : LAttrs)
+    LNameValMap[NameValuePair.first] = NameValuePair.second;
+
+  return std::any_of(
+      RAttrs.begin(), RAttrs.end(),
+      [&](const std::pair<std::string, std::string> &NameValuePair) {
+        auto It = LNameValMap.find(NameValuePair.first);
+        return It != LNameValMap.end() && NameValuePair.second != It->second;
+      });
 }
 
 template <typename AddIRAttrT>
@@ -2574,15 +2621,19 @@ static bool checkSYCLAddIRAttributesMergeability(const AddIRAttrT &NewAttr,
                                                  const AddIRAttrT &ExistingAttr,
                                                  SemaSYCL &S) {
   ASTContext &Context = S.getASTContext();
-  // If there are no dependent argument expressions and the filters or the
-  // attributes are different, then fail due to differing duplicates.
-  if (!S.hasDependentExpr(NewAttr.args_begin(), NewAttr.args_size()) &&
-      !S.hasDependentExpr(ExistingAttr.args_begin(),
-                          ExistingAttr.args_size()) &&
-      (NewAttr.getAttributeFilter() != ExistingAttr.getAttributeFilter() ||
-       !hasSameSYCLAddIRAttributes(
-           NewAttr.getAttributeNameValuePairs(Context),
-           ExistingAttr.getAttributeNameValuePairs(Context)))) {
+
+  // If there are dependent argument expressions, then merging cannot be done
+  // yet. In that case, it is deferred till after instantiation.
+  if (S.hasDependentExpr(NewAttr.args_begin(), NewAttr.args_size()) ||
+      S.hasDependentExpr(ExistingAttr.args_begin(), ExistingAttr.args_size()))
+    return true;
+
+  // If the filters differ or the attributes are conflicting, then fail due to
+  // differing duplicates.
+  if (NewAttr.getAttributeFilter() != ExistingAttr.getAttributeFilter() ||
+      hasConflictingSYCLAddIRAttributes(
+          NewAttr.getAttributeNameValuePairs(Context),
+          ExistingAttr.getAttributeNameValuePairs(Context))) {
     S.Diag(ExistingAttr.getLoc(), diag::err_duplicate_attribute) << &NewAttr;
     S.Diag(NewAttr.getLoc(), diag::note_conflicting_attribute);
     return true;
@@ -2590,12 +2641,58 @@ static bool checkSYCLAddIRAttributesMergeability(const AddIRAttrT &NewAttr,
   return false;
 }
 
+template <typename AddIRAttrT>
+static AddIRAttrT *getMergedSYCLAddIRAttribute(const AddIRAttrT &Attr1,
+                                               const AddIRAttrT &Attr2,
+                                               SemaSYCL &S) {
+  ASTContext &Context = S.getASTContext();
+  bool AttrHasFilterList = Attr1.hasFilterList();
+
+  // Get the vectors of name-value-pairs here so we can create string references
+  // to them for the map.
+  llvm::SmallVector<std::pair<std::string, std::string>, 4> Attr1NVPairs =
+      Attr1.getAttributeNameValuePairs(Context);
+  llvm::SmallVector<std::pair<std::string, std::string>, 4> Attr2NVPairs =
+      Attr2.getAttributeNameValuePairs(Context);
+
+  // Collect all the unique attribute names and their corresponding values. This
+  // relies on the uniqueness having been confirmed first and that the
+  // attributes appear in the same order as in the name-value-pairs.
+  llvm::SmallMapVector<StringRef, std::pair<Expr *, Expr *>, 4> AttrExprByName;
+  for (const auto &[Attr, NVPairs] : {std::make_pair(Attr1, Attr1NVPairs),
+                                      std::make_pair(Attr2, Attr2NVPairs)}) {
+    for (size_t I = 0; I < NVPairs.size(); ++I) {
+      AttrExprByName[NVPairs[I].first] = std::make_pair(
+          (Attr.args_begin() + AttrHasFilterList)[I],
+          (Attr.args_begin() + AttrHasFilterList + (Attr.args_size() / 2))[I]);
+    }
+  }
+
+  // Create a list of new arguments, starting with the filter if present.
+  llvm::SmallVector<Expr *, 4> NewArgs;
+  NewArgs.resize(AttrExprByName.size() * 2 + AttrHasFilterList);
+  if (AttrHasFilterList)
+    NewArgs[0] = *Attr1.args_begin();
+
+  // Then insert all the unique attributes found previously.
+  for (size_t I = 0; I < AttrExprByName.size(); ++I) {
+    const std::pair<Expr *, Expr *> &Exprs = AttrExprByName.begin()[I].second;
+    NewArgs[I + AttrHasFilterList] = Exprs.first;
+    NewArgs[I + AttrExprByName.size() + AttrHasFilterList] = Exprs.second;
+  }
+
+  return AddIRAttrT::Create(Context, NewArgs.data(), NewArgs.size(), Attr1);
+}
+
 SYCLAddIRAttributesFunctionAttr *SemaSYCL::mergeSYCLAddIRAttributesFunctionAttr(
     Decl *D, const SYCLAddIRAttributesFunctionAttr &A) {
   if (const auto *ExistingAttr =
           D->getAttr<SYCLAddIRAttributesFunctionAttr>()) {
-    checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this);
-    return nullptr;
+    if (checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this))
+      return nullptr;
+
+    D->dropAttr<SYCLAddIRAttributesFunctionAttr>();
+    return getMergedSYCLAddIRAttribute(A, *ExistingAttr, *this);
   }
   ASTContext &Context = getASTContext();
   return A.clone(Context);
@@ -2618,8 +2715,11 @@ SemaSYCL::mergeSYCLAddIRAttributesKernelParameterAttr(
     Decl *D, const SYCLAddIRAttributesKernelParameterAttr &A) {
   if (const auto *ExistingAttr =
           D->getAttr<SYCLAddIRAttributesKernelParameterAttr>()) {
-    checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this);
-    return nullptr;
+    if (checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this))
+      return nullptr;
+
+    D->dropAttr<SYCLAddIRAttributesKernelParameterAttr>();
+    return getMergedSYCLAddIRAttribute(A, *ExistingAttr, *this);
   }
   ASTContext &Context = getASTContext();
   return A.clone(Context);
@@ -2642,8 +2742,11 @@ SemaSYCL::mergeSYCLAddIRAttributesGlobalVariableAttr(
     Decl *D, const SYCLAddIRAttributesGlobalVariableAttr &A) {
   if (const auto *ExistingAttr =
           D->getAttr<SYCLAddIRAttributesGlobalVariableAttr>()) {
-    checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this);
-    return nullptr;
+    if (checkSYCLAddIRAttributesMergeability(A, *ExistingAttr, *this))
+      return nullptr;
+
+    D->dropAttr<SYCLAddIRAttributesGlobalVariableAttr>();
+    return getMergedSYCLAddIRAttribute(A, *ExistingAttr, *this);
   }
   ASTContext &Context = getASTContext();
   return A.clone(Context);
diff --git a/clang/test/AST/ast-attr-add-ir-attributes-merge.cpp b/clang/test/AST/ast-attr-add-ir-attributes-merge.cpp
index 2773a30e1e20e..5211295138e9d 100644
--- a/clang/test/AST/ast-attr-add-ir-attributes-merge.cpp
+++ b/clang/test/AST/ast-attr-add-ir-attributes-merge.cpp
@@ -33,6 +33,289 @@
 [[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl1();
 void FunctionRedecl1();
 
+// CHECK:      FunctionDecl [[FunctionRedecl2ID1:0x[0-9a-f]+]] {{.*}} FunctionRedecl2 'void ()'
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl2ID2:0x[0-9a-f]+]] prev [[FunctionRedecl2ID1]] {{.*}} FunctionRedecl2 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl2ID3:0x[0-9a-f]+]] prev [[FunctionRedecl2ID2]] {{.*}} FunctionRedecl2 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl2ID4:0x[0-9a-f]+]] prev [[FunctionRedecl2ID3]] {{.*}} FunctionRedecl2 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl {{.*}} prev [[FunctionRedecl2ID4]] {{.*}} FunctionRedecl2 'void ()'
+// CHECK-NEXT:   CompoundStmt
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+void FunctionRedecl2();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl2();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl2();
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]] void FunctionRedecl2();
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]] void FunctionRedecl2(){};
+
+// CHECK:      FunctionDecl [[FunctionRedecl3ID1:0x[0-9a-f]+]] {{.*}} FunctionRedecl3 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl {{.*}} prev [[FunctionRedecl3ID1]] {{.*}} FunctionRedecl3 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+[[__sycl_detail__::add_ir_attributes_function({"Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();
+void FunctionRedecl3();
+
+// CHECK:      FunctionDecl [[FunctionRedecl4ID1:0x[0-9a-f]+]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl4ID2:0x[0-9a-f]+]] prev [[FunctionRedecl4ID1]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl4ID3:0x[0-9a-f]+]] prev [[FunctionRedecl4ID2]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl4ID4:0x[0-9a-f]+]] prev [[FunctionRedecl4ID3]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl [[FunctionRedecl4ID5:0x[0-9a-f]+]] prev [[FunctionRedecl4ID4]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: FunctionDecl {{.*}} prev [[FunctionRedecl4ID5]] {{.*}} FunctionRedecl4 'void ()'
+// CHECK-NEXT:   CompoundStmt
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr3", false)]] void FunctionRedecl4(){};
+
+// CHECK:      FunctionDecl {{.*}} FunctionDecl2 'void ()'
+// CHECK-NEXT:   CompoundStmt
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]]
+void FunctionDecl2(){};
+
+// CHECK:      FunctionDecl {{.*}} FunctionDecl3 'void ()'
+// CHECK-NEXT:   CompoundStmt {{.*}}
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr {{.*}}
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+[[__sycl_detail__::add_ir_attributes_function({"Attr3"}, "Attr1", "Attr2", 1, true)]]
+void FunctionDecl3(){};
+
+// CHECK:      FunctionDecl {{.*}} FunctionDecl4 'void ()'
+// CHECK-NEXT:   CompoundStmt {{.*}}
+// CHECK-NEXT:   SYCLAddIRAttributesFunctionAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr3", false)]]
+void FunctionDecl4(){};
+
 // CHECK:      CXXRecordDecl [[GlobalVarStructRedecl1ID1:0x[0-9a-f]+]] {{.*}} struct GlobalVarStructRedecl1
 // CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
 // CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
@@ -47,7 +330,74 @@ void FunctionRedecl1();
 // CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
 // CHECK-NEXT:       value: Int 1
 // CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
-// CHECK-NEXT: CXXRecordDecl {{.*}} prev [[GlobalVarStructRedecl1ID1]] {{.*}} struct GlobalVarStructRedecl1
+// CHECK-NEXT: CXXRecordDecl {{.*}} prev [[GlobalVarStructRedecl1ID1]] {{.*}} struct GlobalVarStructRedecl1
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl1;
+struct GlobalVarStructRedecl1;
+
+// CHECK:      CXXRecordDecl [[GlobalVarStructRedecl2ID1:0x[0-9a-f]+]] {{.*}} struct GlobalVarStructRedecl2
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl2ID2:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl2ID1]] {{.*}} struct GlobalVarStructRedecl2
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl2ID3:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl2ID2]] {{.*}} struct GlobalVarStructRedecl2
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl2ID4:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl2ID3]] {{.*}} struct GlobalVarStructRedecl2
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl {{.*}} prev [[GlobalVarStructRedecl2ID4]] {{.*}} struct GlobalVarStructRedecl2 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
 // CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
 // CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
 // CHECK-NEXT:       value: LValue
@@ -55,14 +405,246 @@ void FunctionRedecl1();
 // CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
 // CHECK-NEXT:       value: LValue
 // CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
 // CHECK-NEXT:     ConstantExpr {{.*}} 'int'
 // CHECK-NEXT:       value: Int 1
 // CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
 // CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
 // CHECK-NEXT:       value: Int 1
 // CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
-struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl1;
-struct GlobalVarStructRedecl1;
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructRedecl2
+struct GlobalVarStructRedecl2;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl2;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl2;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl2;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl2{};
+
+// CHECK:      CXXRecordDecl [[GlobalVarStructRedecl3ID1:0x[0-9a-f]+]] {{.*}} struct GlobalVarStructRedecl3
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl3ID2:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl3ID1]] {{.*}} struct GlobalVarStructRedecl3
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl3ID3:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl3ID2]] {{.*}} struct GlobalVarStructRedecl3
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr {{.*}} Inherited
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl [[GlobalVarStructRedecl3ID4:0x[0-9a-f]+]] prev [[GlobalVarStructRedecl3ID3]] {{.*}} struct GlobalVarStructRedecl3
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr {{.*}} Inherited
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl {{.*}} prev [[GlobalVarStructRedecl3ID4]] {{.*}} struct GlobalVarStructRedecl3 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr {{.*}} Inherited
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructRedecl3
+struct GlobalVarStructRedecl3;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl3;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl3{};
+
+// CHECK:      CXXRecordDecl [[GlobalVarStructRedecl4ID1:0x[0-9a-f]+]] {{.*}} struct GlobalVarStructRedecl4
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT: CXXRecordDecl {{.*}} prev [[GlobalVarStructRedecl4ID1]] {{.*}} struct GlobalVarStructRedecl4 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr {{.*}} Inherited
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructRedecl4
+struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl4;
+struct GlobalVarStructRedecl4{};
+
+// CHECK:      CXXRecordDecl {{.*}} struct GlobalVarStructDecl1 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructDecl1
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]]
+GlobalVarStructDecl1{};
+
+// CHECK:      CXXRecordDecl {{.*}} struct GlobalVarStructDecl2 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructDecl2
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr3"}, "Attr1", "Attr2", 1, true)]]
+GlobalVarStructDecl2{};
+
+// CHECK:      CXXRecordDecl {{.*}} struct GlobalVarStructDecl3 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLAddIRAttributesGlobalVariableAttr
+// CHECK-NEXT:     InitListExpr {{.*}} 'void'
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:       value: LValue
+// CHECK-NEXT:       StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 0
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:     ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:       value: Int 1
+// CHECK-NEXT:       CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct GlobalVarStructDecl3
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr3", false)]]
+GlobalVarStructDecl3{};
 
 // CHECK:      CXXRecordDecl {{.*}} referenced struct GlobalVarStructBase definition
 // CHECK-NEXT:   DefinitionData
@@ -217,3 +799,96 @@ struct __attribute__((sycl_special_class)) SpecialClassStructInherit1 : SpecialC
 struct __attribute__((sycl_special_class)) SpecialClassStructInherit2 : SpecialClassStructInherit1 {
   void __init([[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr3", false)]] int x) override {}
 };
+
+// CHECK:      CXXRecordDecl {{.*}} struct SpecialClassStruct1 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLSpecialClassAttr
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct SpecialClassStruct1
+// CHECK-NEXT:   CXXMethodDecl {{.*}} __init 'void (int)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} x 'int'
+// CHECK-NEXT:       SYCLAddIRAttributesKernelParameterAttr
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue 
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue 
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue 
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:           value: Int 0
+// CHECK-NEXT:           CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:         ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:           value: Int 1
+// CHECK-NEXT:           CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:         ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:           value: Int 1
+// CHECK-NEXT:           IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     CompoundStmt
+// CHECK-NEXT:   CXXMethodDecl {{.*}} implicit operator= 'SpecialClassStruct1 &(const SpecialClassStruct1 &)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} 'const SpecialClassStruct1 &'
+// CHECK-NEXT:   CXXMethodDecl {{.*}} implicit operator= 'SpecialClassStruct1 &(SpecialClassStruct1 &&)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} 'SpecialClassStruct1 &&'
+// CHECK-NEXT:   CXXDestructorDecl {{.*}} implicit ~SpecialClassStruct1 'void ()'
+struct __attribute__((sycl_special_class)) SpecialClassStruct1 {
+  virtual void __init(
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr1", "Attr2", 1, true)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr2", "Attr1", true, 1)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr3", false)]]
+    int x) {}
+};
+
+// CHECK:      CXXRecordDecl {{.*}} struct SpecialClassStruct2 definition
+// CHECK-NEXT:   DefinitionData
+// CHECK-NEXT:     DefaultConstructor
+// CHECK-NEXT:     CopyConstructor
+// CHECK-NEXT:     MoveConstructor
+// CHECK-NEXT:     CopyAssignment
+// CHECK-NEXT:     MoveAssignment
+// CHECK-NEXT:     Destructor
+// CHECK-NEXT:   SYCLSpecialClassAttr {{.*}}
+// CHECK-NEXT:   CXXRecordDecl {{.*}} implicit struct SpecialClassStruct2
+// CHECK-NEXT:   CXXMethodDecl {{.*}} __init 'void (int)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} x 'int'
+// CHECK-NEXT:       SYCLAddIRAttributesKernelParameterAttr {{.*}}
+// CHECK-NEXT:         InitListExpr {{.*}} 'void'
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr3"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr2"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'const char[6]' lvalue
+// CHECK-NEXT:           value: LValue
+// CHECK-NEXT:           StringLiteral {{.*}} 'const char[6]' lvalue "Attr1"
+// CHECK-NEXT:         ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:           value: Int 0
+// CHECK-NEXT:           CXXBoolLiteralExpr {{.*}} 'bool' false
+// CHECK-NEXT:         ConstantExpr {{.*}} 'bool'
+// CHECK-NEXT:           value: Int 1
+// CHECK-NEXT:           CXXBoolLiteralExpr {{.*}} 'bool' true
+// CHECK-NEXT:         ConstantExpr {{.*}} 'int'
+// CHECK-NEXT:           value: Int 1
+// CHECK-NEXT:           IntegerLiteral {{.*}} 'int' 1
+// CHECK-NEXT:     CompoundStmt {{.*}}
+// CHECK-NEXT:   CXXMethodDecl {{.*}} implicit operator= 'SpecialClassStruct2 &(const SpecialClassStruct2 &)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} 'const SpecialClassStruct2 &'
+// CHECK-NEXT:   CXXMethodDecl {{.*}} implicit operator= 'SpecialClassStruct2 &(SpecialClassStruct2 &&)'
+// CHECK-NEXT:     ParmVarDecl {{.*}} 'SpecialClassStruct2 &&'
+// CHECK-NEXT:   CXXDestructorDecl {{.*}} implicit ~SpecialClassStruct2 'void ()'
+struct __attribute__((sycl_special_class)) SpecialClassStruct2 {
+  virtual void __init(
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr3", false)]]
+    int x) {}
+};
diff --git a/clang/test/SemaSYCL/attr-add-ir-attributes-merge.cpp b/clang/test/SemaSYCL/attr-add-ir-attributes-merge.cpp
index 05d355afe3ffd..8ab66673bd2c8 100644
--- a/clang/test/SemaSYCL/attr-add-ir-attributes-merge.cpp
+++ b/clang/test/SemaSYCL/attr-add-ir-attributes-merge.cpp
@@ -4,43 +4,143 @@
 // attributes to generate are the same.
 
 void FunctionRedecl1();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl1();  // expected-note {{conflicting attribute is here}}
 [[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl1();
-[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl1();
-[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]] void FunctionRedecl1();  // expected-note {{conflicting attribute is here}}
-[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, false)]] void FunctionRedecl1(); // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
-[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]] void FunctionRedecl1(){};           // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]] void FunctionRedecl1();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, false)]] void FunctionRedecl1(); // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]] void FunctionRedecl1(){};
 
 [[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl2();
 void FunctionRedecl2();
 
 void FunctionRedecl3();
-[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();  // expected-note {{conflicting attribute is here}}
 [[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();
 [[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]] void FunctionRedecl3();
-[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();  // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();
 [[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, false)]] void FunctionRedecl3(); // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
 [[__sycl_detail__::add_ir_attributes_function({"Attr1"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl3();           // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
 [[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl3(){};                    // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}}
 
+void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]] void FunctionRedecl4();
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]] void FunctionRedecl4(){};
+
+[[__sycl_detail__::add_ir_attributes_function({"Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl5();
+void FunctionRedecl5();
+
+void FunctionRedecl6();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl6();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl6();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]] void FunctionRedecl6();
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]] void FunctionRedecl6();
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr3", false)]] void FunctionRedecl6(){};
+
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]]  // expected-error {{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, false)]] // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]]
+void FunctionDecl1(){};
+
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]]  // expected-error 3{{attribute '__sycl_detail__::add_ir_attributes_function' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, false)]] // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_function({"Attr1"}, "Attr1", "Attr2", 1, true)]]           // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]                      // expected-note {{conflicting attribute is here}}
+void FunctionDecl2(){};
+
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_function("Attr3", false)]]
+void FunctionDecl3(){};
+
+[[__sycl_detail__::add_ir_attributes_function({"Attr3"}, "Attr1", "Attr2", 1, true)]]
+void FunctionDecl4(){};
+
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_function({"Attr1", "Attr3"}, "Attr3", false)]]
+void FunctionDecl5(){};
+
 struct GlobalVarStructRedecl1;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl1;  // expected-note {{conflicting attribute is here}}
 struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl1;
-struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl1;
-struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl1;  // expected-note {{conflicting attribute is here}}
-struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, false)]] GlobalVarStructRedecl1; // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
-struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl1{};           // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}}
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl1;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, false)]] GlobalVarStructRedecl1; // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}}
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl1{};
 
 struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl2;
 struct GlobalVarStructRedecl2;
 
 struct GlobalVarStructRedecl3;
-struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;
+struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;  // expected-note {{conflicting attribute is here}}
 struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;
 struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl3;
-struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;  // expected-note {{conflicting attribute is here}}
+struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;
 struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, false)]] GlobalVarStructRedecl3; // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
 struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr1"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3;           // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}} expected-note {{conflicting attribute is here}}
 struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl3{};                    // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}}
 
+struct GlobalVarStructRedecl4;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl4;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl4;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl4;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl4{};
+
+struct GlobalVarStructRedecl5;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl5;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl5;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]] GlobalVarStructRedecl5;
+struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]] GlobalVarStructRedecl5{};
+
+struct [[__sycl_detail__::add_ir_attributes_global_variable({"Attr3"}, "Attr1", "Attr2", 1, true)]] GlobalVarStructRedecl6;
+struct GlobalVarStructRedecl6{};
+
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]]  // expected-error {{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, false)]] // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]]
+GlobalVarStructDecl1{};
+
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]  // expected-error 3{{attribute '__sycl_detail__::add_ir_attributes_global_variable' is already applied with different arguments}}
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, false)]] // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1"}, "Attr1", "Attr2", 1, true)]]           // expected-note {{conflicting attribute is here}}
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]                      // expected-note {{conflicting attribute is here}}
+GlobalVarStructDecl2{};
+
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_global_variable("Attr3", false)]]
+GlobalVarStructDecl3{};
+
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr3"}, "Attr1", "Attr2", 1, true)]]
+GlobalVarStructDecl4{};
+
+struct
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr3", "Attr1"}, "Attr1", "Attr2", 1, true)]]
+[[__sycl_detail__::add_ir_attributes_global_variable({"Attr1", "Attr3"}, "Attr3", false)]]
+GlobalVarStructDecl5{};
+
 struct GlobalVarStructBase {};
 struct [[__sycl_detail__::add_ir_attributes_global_variable("Attr1", "Attr2", 1, true)]] GlobalVarStructInherit1 : GlobalVarStructBase{};
 struct GlobalVarStructInherit2 : GlobalVarStructInherit1 {};
@@ -55,3 +155,28 @@ struct __attribute__((sycl_special_class)) SpecialClassStructInherit1 : SpecialC
 struct __attribute__((sycl_special_class)) SpecialClassStructInherit2 : SpecialClassStructInherit1 {
   void __init([[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr3", false)]] int x) override {}
 };
+
+struct __attribute__((sycl_special_class)) SpecialClassStruct1 {
+  virtual void __init(
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr1", "Attr2", 1, true)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr2", "Attr1", true, 1)]]  // expected-error {{attribute '__sycl_detail__::add_ir_attributes_kernel_parameter' is already applied with different arguments}}
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr1", "Attr2", 1, false)]] // expected-note {{conflicting attribute is here}}
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr3", false)]]
+    int x) {}
+};
+
+struct __attribute__((sycl_special_class)) SpecialClassStruct2 {
+  virtual void __init(
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr1", "Attr2", 1, true)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr2", "Attr1", true, 1)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter("Attr3", false)]]
+    int x) {}
+};
+
+struct __attribute__((sycl_special_class)) SpecialClassStruct3 {
+  virtual void __init(
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr1", "Attr2", 1, true)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr2", "Attr1", true, 1)]]
+    [[__sycl_detail__::add_ir_attributes_kernel_parameter({"Attr1", "Attr3"}, "Attr3", false)]]
+    int x) {}
+};