[SYCL] Forbid declaration of static non-const variable inside kernel.

clang/lib/Sema/SemaDecl.cpp

@@ -6945,6 +6945,13 @@ NamedDecl *Sema::ActOnVariableDeclarator(
       NewVD->setTSCSpec(TSCS);
   }
 
+  // Static variables declared inside SYCL device code must be const or
+  // constexpr
+  if (getLangOpts().SYCLIsDevice && SCSpec == DeclSpec::SCS_static &&
+      !R.isConstant(Context))
+    SYCLDiagIfDeviceCode(D.getIdentifierLoc(), diag::err_sycl_restrict)
+        << Sema::KernelNonConstStaticDataVariable;
+
   switch (D.getDeclSpec().getConstexprSpecifier()) {
   case CSK_unspecified:
     break;

clang/test/CodeGenSYCL/address-space-of-returns.cpp

@@ -10,13 +10,14 @@ const char *ret_char() {
 // CHECK: ret i8 addrspace(4)* addrspacecast (i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0) to i8 addrspace(4)*)
 
 const char *ret_arr() {
-  static char Arr[42];
+  const static char Arr[36] = "Carrots, cabbage, radish, potatoes!";
   return Arr;
 }
-// CHECK: ret i8 addrspace(4)* getelementptr inbounds ([42 x i8], [42 x i8] addrspace(4)* addrspacecast ([42 x i8] addrspace(1)* @{{.*}}ret_arr{{.*}}Arr to [42 x i8] addrspace(4)*), i64 0, i64 0)
+
+// CHECK: ret i8 addrspace(4)* getelementptr inbounds ([36 x i8], [36 x i8] addrspace(4)* addrspacecast ([36 x i8] addrspace(1)* @{{.*}}ret_arr{{.*}}Arr to [36 x i8] addrspace(4)*), i64 0, i64 0)
 
 const char &ret_ref() {
-  static char a = 'A';
+  const static char a = 'A';
   return a;
 }
 // CHECK: ret i8 addrspace(4)* addrspacecast (i8 addrspace(1)* @{{.*}}ret_ref{{.*}} to i8 addrspace(4)*)

clang/test/CodeGenSYCL/address-space-swap.cpp

@@ -3,8 +3,8 @@
 
 
 void test() {
-  static int foo = 0x42;
-// CHECK: @[[FOO:[a-zA-Z0-9_]+]] = internal addrspace(1) global i32 66, align 4
+ int foo = 0x42;
+// CHECK: %[[FOO:[a-zA-Z0-9_]+]] = alloca i32, align 4 
   int i = 43;
 // CHECK: %[[I:[a-zA-Z0-9_]+]] = alloca i32, align 4
 
@@ -19,8 +19,9 @@ void test() {
 // CHECK: call spir_func void @_ZSt4swap{{.*}}(i32 addrspace(4)* addrspace(4)* dereferenceable(8) %[[P1GEN]], i32 addrspace(4)* addrspace(4)* dereferenceable(8) %[[P2GEN]])
 
   std::swap(foo, i);
-// CHECK: %[[ICAST:[a-zA-Z0-9_]+]] = addrspacecast i32* %[[I]] to i32 addrspace(4)*
-// CHECK: call spir_func void @_ZSt4swap{{.*}}(i32 addrspace(4)* dereferenceable(4) addrspacecast (i32 addrspace(1)* @[[FOO]] to i32 addrspace(4)*), i32 addrspace(4)* dereferenceable(4) %[[ICAST]])
+// CHECK: %[[FOOCAST:[a-zA-Z0-9_]+]] = addrspacecast i32* %[[FOO]] to i32 addrspace(4)*
+// CHECK: %[[ICAST:[a-zA-Z0-9_]+]] = addrspacecast i32* %[[I]] to i32 addrspace(4)* 
+// CHECK: call spir_func void @_ZSt4swap{{.*}}(i32 addrspace(4)* dereferenceable(4) %[[FOOCAST]], i32 addrspace(4)* dereferenceable(4) %[[ICAST]])
 }
 
 

clang/test/CodeGenSYCL/intel-fpga-local.cpp

@@ -25,24 +25,18 @@
 
 // CHECK-BOTH: @llvm.global.annotations
 // CHECK-DEVICE-SAME: { i8* addrspacecast (i8 addrspace(1)* bitcast (i32 addrspace(1)* @_ZZ15attrs_on_staticvE15static_numbanks to i8 addrspace(1)*) to i8*)
-// CHECK-DEVICE-SAME: [[ANN_numbanks_4]]{{.*}}i32 38
-// CHECK-DEVICE-SAME: { i8* addrspacecast (i8 addrspace(1)* bitcast (i32 addrspace(1)* @_ZZ15attrs_on_staticvE15static_annotate to i8 addrspace(1)*) to i8*)
+// CHECK-DEVICE-SAME: [[ANN_numbanks_4]], i32 0
+// CHECK-DEVICE-SAME: { i8* addrspacecast (i8 addrspace(1)* bitcast (i32 addrspace(1)* @_ZZ15attrs_on_staticvE15static_annotate to i8 addrspace(1)*) to i8*) 
 // CHECK-HOST-SAME: { i8* bitcast (i32* @_ZZ15attrs_on_staticvE15static_annotate to i8*)
-// CHECK-BOTH-SAME: [[ANN_annotate]]{{.*}}i32 42
+// CHECK-BOTH-SAME: [[ANN_annotate]], i32 0
 
 // CHECK-HOST-NOT: llvm.var.annotation
 // CHECK-HOST-NOT: llvm.ptr.annotation
 
 void attrs_on_static() {
   int a = 42;
-  static int static_numbanks [[intelfpga::numbanks(4)]];
-  // CHECK-BOTH: load{{.*}}static_numbanks
-  // CHECK-BOTH: store{{.*}}static_numbanks
-  static_numbanks = static_numbanks + a;
-  static int static_annotate [[clang::annotate("foobar")]];
-  // CHECK-BOTH: load{{.*}}static_annotate
-  // CHECK-BOTH: store{{.*}}static_annotate
-  static_annotate = static_annotate + a;
+  const static int static_numbanks [[intelfpga::numbanks(4)]] = 20;
+  const static int static_annotate [[clang::annotate("foobar")]] = 30;
 }
 
 void attrs_on_var() {

clang/test/SemaSYCL/sycl-device-const-static.cpp

@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -verify -fsyntax-only -fsycl-is-device %s
+
+void usage() {
+  // expected-error@+1{{SYCL kernel cannot use a non-const static data variable}}
+  static int m; 
+}
+
+template <typename Name, typename Func>
+__attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
+  // expected-error@+1{{SYCL kernel cannot use a non-const static data variable}}
+  static int z;
+  // expected-note-re@+2{{called by 'kernel_single_task<fake_kernel, (lambda at {{.*}})>}}
+  // expected-note-re@+1{{called by 'kernel_single_task<fake_kernel, (lambda at {{.*}})>}}
+  kernelFunc();
+}
+
+int main() {
+  static int n;
+  kernel_single_task<class fake_kernel>([]() {
+    //  expected-note@+1{{called by 'operator()'}}
+    usage();
+    // expected-error@+1{{SYCL kernel cannot use a non-const static data variable}}
+    static int g;
+  });
+
+  return 0;
+}