[SYCL][OpenMP] Implement thread-local storage restriction

Summary:
SYCL and OpenMP prohibits thread local storage in device code,
so this commit ensures that error is emitted for device code and not
emitted for host code when host target supports it.

Reviewers: jdoerfert, erichkeane, bader

Reviewed By: jdoerfert, erichkeane

Subscribers: guansong, riccibruno, ABataev, yaxunl, ebevhan, Anastasia, sstefan1, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81641

clang/lib/Sema/SemaDecl.cpp

@@ -7077,7 +7077,8 @@ NamedDecl *Sema::ActOnVariableDeclarator(
            diag::err_thread_non_global)
         << DeclSpec::getSpecifierName(TSCS);
     else if (!Context.getTargetInfo().isTLSSupported()) {
-      if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice) {
+      if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice ||
+          getLangOpts().SYCLIsDevice) {
         // Postpone error emission until we've collected attributes required to
         // figure out whether it's a host or device variable and whether the
         // error should be ignored.
@@ -7179,13 +7180,18 @@ NamedDecl *Sema::ActOnVariableDeclarator(
   // Handle attributes prior to checking for duplicates in MergeVarDecl
   ProcessDeclAttributes(S, NewVD, D);
 
-  if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice) {
+  if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice ||
+      getLangOpts().SYCLIsDevice) {
     if (EmitTLSUnsupportedError &&
         ((getLangOpts().CUDA && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) ||
          (getLangOpts().OpenMPIsDevice &&
           OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(NewVD))))
       Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
            diag::err_thread_unsupported);
+
+    if (EmitTLSUnsupportedError &&
+        (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice)))
+      targetDiag(D.getIdentifierLoc(), diag::err_thread_unsupported);
     // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
     // storage [duration]."
     if (SC == SC_None && S->getFnParent() != nullptr &&

clang/lib/Sema/SemaExpr.cpp

@@ -355,10 +355,16 @@ bool Sema::DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
 
   diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc);
 
-  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice))
+  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice)) {
     if (const auto *VD = dyn_cast<ValueDecl>(D))
       checkDeviceDecl(VD, Loc);
 
+    if (!Context.getTargetInfo().isTLSSupported())
+      if (const auto *VD = dyn_cast<VarDecl>(D))
+        if (VD->getTLSKind() != VarDecl::TLS_None)
+          targetDiag(*Locs.begin(), diag::err_thread_unsupported);
+  }
+
   if (isa<ParmVarDecl>(D) && isa<RequiresExprBodyDecl>(D->getDeclContext()) &&
       !isUnevaluatedContext()) {
     // C++ [expr.prim.req.nested] p3

clang/test/OpenMP/nvptx_prohibit_thread_local.cpp

@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -fopenmp -x c++ -triple x86_64-unknown-linux -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple nvptx64-unknown-unknown -aux-triple x86_64-unknown-linux -fopenmp-targets=nvptx64-nvidia-cuda %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-host.bc -fsyntax-only
+
+thread_local const int prohobit_ns_scope = 0;
+thread_local int prohobit_ns_scope2 = 0;
+thread_local const int allow_ns_scope = 0;
+
+struct S {
+  static const thread_local int prohibit_static_member;
+  static thread_local int prohibit_static_member2;
+};
+
+struct T {
+  static const thread_local int allow_static_member;
+};
+
+void foo() {
+  // expected-error@+1{{thread-local storage is not supported for the current target}}
+  thread_local const int prohibit_local = 0;
+  // expected-error@+1{{thread-local storage is not supported for the current target}}
+  thread_local int prohibit_local2;
+}
+
+void bar() { thread_local int allow_local; }
+
+void usage() {
+  // expected-note@+1 {{called by}}
+  foo();
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)prohobit_ns_scope;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)prohobit_ns_scope2;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)S::prohibit_static_member;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)S::prohibit_static_member2;
+}
+
+int main() {
+  // expected-note@+2 2{{called by}}
+#pragma omp target
+  usage();
+  return 0;
+}

clang/test/OpenMP/nvptx_target_codegen.cpp

@@ -160,7 +160,7 @@ int foo(int n) {
 // CHECK: [[EXIT]]
 // CHECK: ret void
 
-// CHECK: define {{.*}}void [[T2:@__omp_offloading_.+foo.+l200]](i[[SZ:32|64]] [[ARG1:%[a-zA-Z_]+]], i[[SZ:32|64]] [[ID:%[a-zA-Z_]+]])
+// CHECK: define {{.*}}void [[T2:@__omp_offloading_.+foo.+l200]](i[[SZ:32|64]] [[ARG1:%[a-zA-Z_]+]])
 // CHECK: [[AA_ADDR:%.+]] = alloca i[[SZ]],
 // CHECK: store i[[SZ]] [[ARG1]], i[[SZ]]* [[AA_ADDR]],
 // CHECK: [[AA_CADDR:%.+]] = bitcast i[[SZ]]* [[AA_ADDR]] to i16*
@@ -200,7 +200,7 @@ int foo(int n) {
 #pragma omp target if (1)
   {
     aa += 1;
-    id = aa;
+    aa += 2;
   }
 
 // CHECK-LABEL: define {{.*}}void {{@__omp_offloading_.+foo.+l310}}_worker()

clang/test/SemaSYCL/prohibit-thread-local.cpp

@@ -0,0 +1,48 @@
+// RUN: %clang_cc1 -fsycl -fsycl-is-device -triple spir64 -verify -fsyntax-only %s
+
+thread_local const int prohobit_ns_scope = 0;
+thread_local int prohobit_ns_scope2 = 0;
+thread_local const int allow_ns_scope = 0;
+
+struct S {
+  static const thread_local int prohibit_static_member;
+  static thread_local int prohibit_static_member2;
+};
+
+struct T {
+  static const thread_local int allow_static_member;
+};
+
+void foo() {
+  // expected-error@+1{{thread-local storage is not supported for the current target}}
+  thread_local const int prohibit_local = 0;
+  // expected-error@+1{{thread-local storage is not supported for the current target}}
+  thread_local int prohibit_local2;
+}
+
+void bar() { thread_local int allow_local; }
+
+void usage() {
+  // expected-note@+1 {{called by}}
+  foo();
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)prohobit_ns_scope;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)prohobit_ns_scope2;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)S::prohibit_static_member;
+  // expected-error@+1 {{thread-local storage is not supported for the current target}}
+  (void)S::prohibit_static_member2;
+}
+
+template <typename name, typename Func>
+__attribute__((sycl_kernel))
+// expected-note@+2 2{{called by}}
+void
+kernel_single_task(Func kernelFunc) { kernelFunc(); }
+
+int main() {
+  // expected-note@+1 2{{called by}}
+  kernel_single_task<class fake_kernel>([]() { usage(); });
+  return 0;
+}