[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

@@ -1,35 +1,33 @@
 // RUN: %clang -fsycl-device-only -S -emit-llvm %s -o - | FileCheck %s
 #include <algorithm>
 
-
 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
+  // CHECK: %[[I:[a-zA-Z0-9_]+]] = alloca i32, align 4
 
-  int* p1 = &foo;
-  int* p2 = &i;
-// CHECK: %[[P1:[a-zA-Z0-9_]+]] = alloca i32 addrspace(4)*, align 8
-// CHECK: %[[P2:[a-zA-Z0-9_]+]] = alloca i32 addrspace(4)*, align 8
-// CHECK: %[[P1GEN:[a-zA-Z0-9_]+]] = addrspacecast i32 addrspace(4)** %[[P1]] to i32 addrspace(4)* addrspace(4)*
-// CHECK: %[[P2GEN:[a-zA-Z0-9_]+]] = addrspacecast i32 addrspace(4)** %[[P2]] to i32 addrspace(4)* addrspace(4)*
+  int *p1 = &foo;
+  int *p2 = &i;
+  // CHECK: %[[P1:[a-zA-Z0-9_]+]] = alloca i32 addrspace(4)*, align 8
+  // CHECK: %[[P2:[a-zA-Z0-9_]+]] = alloca i32 addrspace(4)*, align 8
+  // CHECK: %[[P1GEN:[a-zA-Z0-9_]+]] = addrspacecast i32 addrspace(4)** %[[P1]] to i32 addrspace(4)* addrspace(4)*
+  // CHECK: %[[P2GEN:[a-zA-Z0-9_]+]] = addrspacecast i32 addrspace(4)** %[[P2]] to i32 addrspace(4)* addrspace(4)*
 
   std::swap(p1, p2);
-// CHECK: call spir_func void @_ZSt4swap{{.*}}(i32 addrspace(4)* addrspace(4)* dereferenceable(8) %[[P1GEN]], i32 addrspace(4)* addrspace(4)* dereferenceable(8) %[[P2GEN]])
+  // 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]])
 }
 
-
 template <typename name, typename Func>
 __attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
   kernelFunc();
 }
 
-
 int main() {
   kernel_single_task<class fake_kernel>([]() { test(); });
   return 0;

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

@@ -1,7 +1,9 @@
 // RUN: %clang_cc1 -triple spir64-unknown-unknown-sycldevice -disable-llvm-passes -fsycl-is-device -emit-llvm %s -o - | FileCheck %s -check-prefixes CHECK-DEVICE,CHECK-BOTH
 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -disable-llvm-passes -emit-llvm %s -o - | FileCheck %s -check-prefixes CHECK-HOST,CHECK-BOTH
 
+// CHECK-BOTH: @_ZZ15attrs_on_staticvE15static_numbanks = internal{{.*}}constant i32 20, align 4
 // CHECK-DEVICE:  [[ANN_numbanks_4:@.str]] = {{.*}}{memory:DEFAULT}{sizeinfo:4}{numbanks:4}
+// CHECK-BOTH: @_ZZ15attrs_on_staticvE15static_annotate = internal{{.*}}constant i32 30, align 4
 // CHECK-BOTH:    [[ANN_annotate:@.str[.0-9]*]] = {{.*}}foobar
 // CHECK-DEVICE:  [[ANN_register:@.str.[0-9]*]] = {{.*}}{register:1}
 // CHECK-DEVICE:  [[ANN_memory_default:@.str.[0-9]*]] = {{.*}}{memory:DEFAULT}{sizeinfo:4}
@@ -25,24 +27,17 @@
 
 // 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: [[ANN_numbanks_4]]{{.*}} i32 39
 // 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 40
 
 // 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 +1,29 @@
+// 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 s1;
+  const static int cs = 0;
+  constexpr static int ces = 0;
+}
+
+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 s2;
+  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 s3;
+  });
+
+  return 0;
+}