[SYCL] Improve kernel name diagnostics implementation

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -11167,12 +11167,15 @@ def err_ext_int_max_size : Error<"%select{signed|unsigned}0 _ExtInt of bit "
 def err_esimd_glob_cant_init : Error<
   "SYCL explicit SIMD does not permit private global variable to have an initializer">;
 
-def err_sycl_kernel_incorrectly_named : Error<"%0 is an invalid kernel name type">;
-def note_invalid_type_in_sycl_kernel : Note<
-  "%select{%1 should be globally-visible"
+def err_nullptr_t_type_in_sycl_kernel : Error<"%0 is an invalid kernel name, "
+                                        "'std::nullptr_t' is declared in the 'std' namespace ">;
+def err_invalid_std_type_in_sycl_kernel : Error<"%0 is an invalid kernel name, " 
+                                          "%q1 is declared in the 'std' namespace ">;
+
+def err_sycl_kernel_incorrectly_named : Error<
+  "%select{%1 should be globally visible"
   "|unscoped enum %1 requires fixed underlying type"
-  "|type %1 cannot be in the \"std\" namespace"
-  "|unnamed type used in a SYCL kernel name"
+  "|unnamed lambda %1 used"
   "}0">;
 
 def err_sycl_kernel_not_function_object

clang/lib/Sema/SemaSYCL.cpp

@@ -2958,21 +2958,14 @@ class SYCLKernelNameTypeVisitor
   void Visit(QualType T) {
     if (T.isNull())
       return;
+
     const CXXRecordDecl *RD = T->getAsCXXRecordDecl();
-    if (!RD) {
-      if (T->isNullPtrType()) {
-        S.Diag(KernelInvocationFuncLoc, diag::err_sycl_kernel_incorrectly_named)
-            << KernelNameType;
-        S.Diag(KernelInvocationFuncLoc, diag::note_invalid_type_in_sycl_kernel)
-            << /* kernel name cannot be a type in the std namespace */ 2 << T;
-        IsInvalid = true;
-      }
-      return;
-    }
     // If KernelNameType has template args visit each template arg via
     // ConstTemplateArgumentVisitor
-    if (const auto *TSD = dyn_cast<ClassTemplateSpecializationDecl>(RD)) {
+    if (const auto *TSD =
+            dyn_cast_or_null<ClassTemplateSpecializationDecl>(RD)) {
       ArrayRef<TemplateArgument> Args = TSD->getTemplateArgs().asArray();
+
       VisitTemplateArgs(Args);
     } else {
       InnerTypeVisitor::Visit(T.getTypePtr());
@@ -2985,62 +2978,104 @@ class SYCLKernelNameTypeVisitor
     InnerTemplArgVisitor::Visit(TA);
   }
 
-  void VisitEnumType(const EnumType *T) {
-    const EnumDecl *ED = T->getDecl();
-    if (!ED->isScoped() && !ED->isFixed()) {
-      S.Diag(KernelInvocationFuncLoc, diag::err_sycl_kernel_incorrectly_named)
+  void VisitBuiltinType(const BuiltinType *TT) {
+    if (TT->isNullPtrType()) {
+      S.Diag(KernelInvocationFuncLoc, diag::err_nullptr_t_type_in_sycl_kernel)
           << KernelNameType;
-      S.Diag(KernelInvocationFuncLoc, diag::note_invalid_type_in_sycl_kernel)
-          << /* Unscoped enum requires fixed underlying type */ 1
-          << QualType(ED->getTypeForDecl(), 0);
+
       IsInvalid = true;
     }
+    return;
   }
 
-  void VisitRecordType(const RecordType *T) {
-    return VisitTagDecl(T->getDecl());
-  }
+  void VisitTagType(const TagType *TT) {
+    return DiagnoseKernelNameType(TT->getDecl());
+  }
+
+  void DiagnoseKernelNameType(const NamedDecl *DeclNamed) {
+    /*
+    This is a helper function which throws an error if the kernel name
+    declaration is:
+      * declared within namespace 'std' (at any level)
+        e.g., namespace std { namespace literals { class Whatever; } }
+        h.single_task<std::literals::Whatever>([]() {});
+      * declared within an anonymous namespace (at any level)
+        e.g., namespace foo { namespace { class Whatever; } }
+        h.single_task<foo::Whatever>([]() {});
+      * declared within a function
+        e.g., void foo() { struct S { int i; };
+        h.single_task<S>([]() {}); }
+      * declared within another tag
+        e.g., struct S { struct T { int i } t; };
+        h.single_task<S::T>([]() {});
+    */
+
+    if (const auto *ED = dyn_cast<EnumDecl>(DeclNamed)) {
+      if (!ED->isScoped() && !ED->isFixed()) {
+        S.Diag(KernelInvocationFuncLoc, diag::err_sycl_kernel_incorrectly_named)
+            << /* unscoped enum requires fixed underlying type */ 1
+            << DeclNamed;
+        IsInvalid = true;
+      }
+    }
 
-  void VisitTagDecl(const TagDecl *Tag) {
     bool UnnamedLambdaEnabled =
         S.getASTContext().getLangOpts().SYCLUnnamedLambda;
-    const DeclContext *DeclCtx = Tag->getDeclContext();
+    const DeclContext *DeclCtx = DeclNamed->getDeclContext();
     if (DeclCtx && !UnnamedLambdaEnabled) {
-      auto *NameSpace = dyn_cast_or_null<NamespaceDecl>(DeclCtx);
-      if (NameSpace && NameSpace->isStdNamespace()) {
-        S.Diag(KernelInvocationFuncLoc, diag::err_sycl_kernel_incorrectly_named)
-            << KernelNameType;
-        S.Diag(KernelInvocationFuncLoc, diag::note_invalid_type_in_sycl_kernel)
-            << /* kernel name cannot be a type in the std namespace */ 2
-            << QualType(Tag->getTypeForDecl(), 0);
-        IsInvalid = true;
-        return;
-      }
-      if (!DeclCtx->isTranslationUnit() && !isa<NamespaceDecl>(DeclCtx)) {
-        const bool KernelNameIsMissing = Tag->getName().empty();
-        if (KernelNameIsMissing) {
-          S.Diag(KernelInvocationFuncLoc,
-                 diag::err_sycl_kernel_incorrectly_named)
-              << KernelNameType;
+
+      // Check if the kernel name declaration is declared within namespace
+      // "std" or "anonymous" namespace (at any level).
+      while (!DeclCtx->isTranslationUnit() && isa<NamespaceDecl>(DeclCtx)) {
+        const auto *NSDecl = cast<NamespaceDecl>(DeclCtx);
+        if (NSDecl->isStdNamespace()) {
           S.Diag(KernelInvocationFuncLoc,
-                 diag::note_invalid_type_in_sycl_kernel)
-              << /* unnamed type used in a SYCL kernel name */ 3;
+                 diag::err_invalid_std_type_in_sycl_kernel)
+              << KernelNameType << DeclNamed;
           IsInvalid = true;
           return;
         }
-        if (Tag->isCompleteDefinition()) {
+        if (NSDecl->isAnonymousNamespace()) {
           S.Diag(KernelInvocationFuncLoc,
                  diag::err_sycl_kernel_incorrectly_named)
+              << /* kernel name should be globally visible */ 0
               << KernelNameType;
-          S.Diag(KernelInvocationFuncLoc,
-                 diag::note_invalid_type_in_sycl_kernel)
-              << /* kernel name is not globally-visible */ 0
-              << QualType(Tag->getTypeForDecl(), 0);
           IsInvalid = true;
-        } else {
-          S.Diag(KernelInvocationFuncLoc, diag::warn_sycl_implicit_decl);
-          S.Diag(Tag->getSourceRange().getBegin(), diag::note_previous_decl)
-              << Tag->getName();
+          return;
+        }
+        DeclCtx = DeclCtx->getParent();
+      }
+
+      // Check if the kernel name is a Tag declaration
+      // local to a non-namespace scope (i.e. Inside a function or within
+      // another Tag etc).
+      if (!DeclCtx->isTranslationUnit() && !isa<NamespaceDecl>(DeclCtx)) {
+        if (const auto *Tag = dyn_cast<TagDecl>(DeclNamed)) {
+          bool UnnamedLambdaUsed = Tag->getIdentifier() == nullptr;
+
+          if (UnnamedLambdaUsed) {
+            S.Diag(KernelInvocationFuncLoc,
+                   diag::err_sycl_kernel_incorrectly_named)
+                << /* unnamed lambda used */ 2 << KernelNameType;
+
+            IsInvalid = true;
+            return;
+          }
+          // Check if the declaration is completely defined within a
+          // function or class/struct.
+
+          if (Tag->isCompleteDefinition()) {
+            S.Diag(KernelInvocationFuncLoc,
+                   diag::err_sycl_kernel_incorrectly_named)
+                << /* kernel name should be globally visible */ 0
+                << KernelNameType;
+
+            IsInvalid = true;
+          } else {
+            S.Diag(KernelInvocationFuncLoc, diag::warn_sycl_implicit_decl);
+            S.Diag(DeclNamed->getLocation(), diag::note_previous_decl)
+                << DeclNamed->getName();
+          }
         }
       }
     }
@@ -3049,15 +3084,15 @@ class SYCLKernelNameTypeVisitor
   void VisitTypeTemplateArgument(const TemplateArgument &TA) {
     QualType T = TA.getAsType();
     if (const auto *ET = T->getAs<EnumType>())
-      VisitEnumType(ET);
+      VisitTagType(ET);
     else
       Visit(T);
   }
 
   void VisitIntegralTemplateArgument(const TemplateArgument &TA) {
     QualType T = TA.getIntegralType();
     if (const EnumType *ET = T->getAs<EnumType>())
-      VisitEnumType(ET);
+      VisitTagType(ET);
   }
 
   void VisitTemplateTemplateArgument(const TemplateArgument &TA) {
@@ -3068,7 +3103,7 @@ class SYCLKernelNameTypeVisitor
       if (NonTypeTemplateParmDecl *TemplateParam =
               dyn_cast<NonTypeTemplateParmDecl>(P))
         if (const EnumType *ET = TemplateParam->getType()->getAs<EnumType>())
-          VisitEnumType(ET);
+          VisitTagType(ET);
     }
   }
 
@@ -3129,7 +3164,7 @@ void Sema::CheckSYCLKernelCall(FunctionDecl *KernelFunc, SourceRange CallLoc,
 
   // Emit diagnostics for SYCL device kernels only
   if (LangOpts.SYCLIsDevice)
-    KernelNameTypeVisitor.Visit(KernelNameType);
+    KernelNameTypeVisitor.Visit(KernelNameType.getCanonicalType());
   Visitor.VisitRecordBases(KernelObj, FieldChecker, UnionChecker, DecompMarker);
   Visitor.VisitRecordFields(KernelObj, FieldChecker, UnionChecker,
                             DecompMarker);

clang/test/CodeGenSYCL/int_header1.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsycl-is-device -fsycl-int-header=%t.h %s -o %t.out
+// RUN: %clang_cc1 -fsycl-is-device -internal-isystem %S/Inputs -sycl-std=2020 -fsycl-int-header=%t.h %s -o %t.out
 // RUN: FileCheck -input-file=%t.h %s
 
 // CHECK:template <> struct KernelInfo<class KernelName> {
@@ -8,18 +8,15 @@
 // CHECK:template <> struct KernelInfo<::nm1::KernelName3<::nm1::KernelName1>> {
 // CHECK:template <> struct KernelInfo<::nm1::KernelName4<::nm1::nm2::KernelName0>> {
 // CHECK:template <> struct KernelInfo<::nm1::KernelName4<::nm1::KernelName1>> {
-// CHECK:template <> struct KernelInfo<::nm1::KernelName3<KernelName5>> {
-// CHECK:template <> struct KernelInfo<::nm1::KernelName4<KernelName7>> {
 // CHECK:template <> struct KernelInfo<::nm1::KernelName8<::nm1::nm2::C>> {
-// CHECK:template <> struct KernelInfo<::TmplClassInAnonNS<ClassInAnonNS>> {
 // CHECK:template <> struct KernelInfo<::nm1::KernelName9<char>> {
 // CHECK:template <> struct KernelInfo<::nm1::KernelName3<const volatile ::nm1::KernelName3<const volatile char>>> {
 
 // This test checks if the SYCL device compiler is able to generate correct
 // integration header when the kernel name class is expressed in different
 // forms.
 
-#include "Inputs/sycl.hpp"
+#include "sycl.hpp"
 
 template <typename KernelName, typename KernelType>
 __attribute__((sycl_kernel)) void kernel_single_task(const KernelType &kernelFunc) {
@@ -110,29 +107,12 @@ struct MyWrapper {
     kernel_single_task<nm1::KernelName4<nm1::KernelName1>>(
       [=]() { acc.use(); });
 
-    // TIPI
-    // an incomplete template specialization class with incomplete class as
-    // argument forward-declared "in-place"
-    kernel_single_task<nm1::KernelName3<class KernelName5>>(
-      [=]() { acc.use(); });
-
-    // TDPI
-    // a defined template specialization class with incomplete class as
-    // argument forward-declared "in-place"
-    kernel_single_task<nm1::KernelName4<class KernelName7>>(
-      [=]() { acc.use(); });
-
     // TPITD
     // a defined template pack specialization class with defined class
     // as argument declared in a namespace at translation unit scope
     kernel_single_task<nm1::KernelName8<nm1::nm2::C>>(
       [=]() { acc.use(); });
 
-    // kernel name type is a templated class, both the top-level class and the
-    // template argument are declared in the anonymous namespace
-    kernel_single_task<TmplClassInAnonNS<class ClassInAnonNS>>(
-      [=]() { acc.use(); });
-
     // Kernel name type is a templated specialization class with empty template pack argument
     kernel_single_task<nm1::KernelName9<char>>(
         [=]() { acc.use(); });

clang/test/CodeGenSYCL/integration_header.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsycl-is-device -triple spir64-unknown-unknown-sycldevice -fsycl-int-header=%t.h %s -emit-llvm -o %t.ll
+// RUN: %clang_cc1 -fsycl-is-device -triple spir64-unknown-unknown-sycldevice -sycl-std=2020 -fsycl-int-header=%t.h %s -emit-llvm -o %t.ll
 // RUN: FileCheck -input-file=%t.h %s
 //
 // CHECK: #include <CL/sycl/detail/kernel_desc.hpp>
@@ -7,9 +7,6 @@
 // CHECK-NEXT: namespace second_namespace {
 // CHECK-NEXT: template <typename T> class second_kernel;
 // CHECK-NEXT: }
-// CHECK-NEXT: struct X;
-// CHECK-NEXT: template <typename T> struct point;
-// CHECK-NEXT: template <int a, typename T1, typename T2> class third_kernel;
 // CHECK-NEXT: namespace template_arg_ns {
 // CHECK-NEXT: template <int DimX> struct namespaced_arg;
 // CHECK-NEXT: }
@@ -19,7 +16,6 @@
 // CHECK-NEXT: const char* const kernel_names[] = {
 // CHECK-NEXT:   "_ZTSZ4mainE12first_kernel",
 // CHECK-NEXT:   "_ZTSN16second_namespace13second_kernelIcEE",
-// CHECK-NEXT:   "_ZTS12third_kernelILi1Ei5pointIZ4mainE1XEE"
 // CHECK-NEXT:   "_ZTS13fourth_kernelIJN15template_arg_ns14namespaced_argILi1EEEEE"
 // CHECK-NEXT:   "_ZTSZ4mainE16accessor_in_base"
 // CHECK-NEXT: };
@@ -38,11 +34,6 @@
 // CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 6112, 4 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_sampler, 8, 16 },
 // CHECK-EMPTY:
-// CHECK-NEXT:   //--- _ZTS12third_kernelILi1Ei5pointIZ4mainE1XEE
-// CHECK-NEXT:   { kernel_param_kind_t::kind_std_layout, 4, 0 },
-// CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 6112, 4 },
-// CHECK-NEXT:   { kernel_param_kind_t::kind_sampler, 8, 16 },
-// CHECK-EMPTY:
 // CHECK-NEXT:   //--- _ZTS13fourth_kernelIJN15template_arg_ns14namespaced_argILi1EEEEE
 // CHECK-NEXT:   { kernel_param_kind_t::kind_std_layout, 4, 0 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 6112, 4 },
@@ -61,7 +52,6 @@
 //
 // CHECK: template <> struct KernelInfo<class first_kernel> {
 // CHECK: template <> struct KernelInfo<::second_namespace::second_kernel<char>> {
-// CHECK: template <> struct KernelInfo<::third_kernel<1, int, ::point<X>>> {
 // CHECK: template <> struct KernelInfo<::fourth_kernel<::template_arg_ns::namespaced_arg<1>>> {
 
 #include "Inputs/sycl.hpp"
@@ -140,12 +130,6 @@ int main() {
       smplr.use();
     }
   });
-  kernel_single_task<class third_kernel<1, int,point<struct X>>>([=]() {
-    if (i == 13) {
-      acc2.use();
-      smplr.use();
-    }
-  });
 
     kernel_single_task<class fourth_kernel<template_arg_ns::namespaced_arg<1>>>([=]() {
       if (i == 13) {