updated diagnostics - sycl version aware, diff messaging

Signed-off-by: Chris Perkins <chris.perkins@intel.com>

Author: cperkinsintel

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -10969,8 +10969,8 @@ def warn_boolean_attribute_argument_is_not_valid: Warning<
 def err_sycl_attibute_cannot_be_applied_here
     : Error<"%0 attribute cannot be applied to a "
             "static function or function in an anonymous namespace">;
-def warn_sycl_old_version 
-    : Warning<"Older version of SYCL headers encountered.">,
+def warn_sycl_pass_by_value_deprecated 
+    : Warning<"Pass-by-value of kernel functions is deprecated in SYCL 2020.">,
       InGroup<SyclStrict>;
 def warn_sycl_attibute_function_raw_ptr
     : Warning<"SYCL 1.2.1 specification does not allow %0 attribute applied "

clang/lib/Frontend/CompilerInvocation.cpp

@@ -2582,6 +2582,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
     if (const Arg *A = Args.getLastArg(OPT_sycl_std_EQ)) {
       Opts.SYCLVersion = llvm::StringSwitch<unsigned>(A->getValue())
                              .Cases("2017", "1.2.1", "121", "sycl-1.2.1", 2017)
+                             .Case("2020", 2020)
                              .Default(0U);
 
       if (Opts.SYCLVersion == 0U) {

clang/lib/Sema/SemaSYCL.cpp

@@ -736,7 +736,10 @@ static const CXXRecordDecl *getKernelObjectType(Sema &SemaRef,
     return KernelParamTy->getPointeeCXXRecordDecl();
 
   // SYCL 1.2
-  SemaRef.Diag(Caller->getLocation(), diag::warn_sycl_old_version);
+  if (SemaRef.LangOpts.SYCLVersion > 2017)
+    SemaRef.Diag(Caller->getLocation(),
+                 diag::warn_sycl_pass_by_value_deprecated);
+
   return KernelParamTy->getAsCXXRecordDecl();
 }
 

clang/test/CodeGenSYCL/kernel-by-reference.cpp

@@ -1,9 +1,14 @@
-// RUN: %clang_cc1 -triple spir64 -fsycl -fsycl-is-device -verify -fsyntax-only %s
+// RUN: %clang_cc1 -triple spir64 -fsycl -fsycl-is-device -verify -fsyntax-only -sycl-std=2017 -DNODIAG %s
+// RUN: %clang_cc1 -triple spir64 -fsycl -fsycl-is-device -verify -fsyntax-only -sycl-std=2020 -DSYCL2020 %s
+// RUN: %clang_cc1 -triple spir64 -fsycl -fsycl-is-device -verify -fsyntax-only -Wno-sycl-strict -DNODIAG %s
+// RUN: %clang_cc1 -triple spir64 -fsycl -fsycl-is-device -verify -fsyntax-only -sycl-std=2020 -Wno-sycl-strict -DNODIAG %s
 
-// SYCL 1.2 - kernel functions passed directly. (Also no const requirement, though mutable lambdas never supported)
+// SYCL 1.2/2017 - kernel functions passed directly. (Also no const requirement, though mutable lambdas never supported)
 template <typename name, typename Func>
-// expected-warning@+1 {{Older version of SYCL headers encountered.}}
-__attribute__((sycl_kernel)) void sycl_12_single_task(Func kernelFunc) {
+#if defined(SYCL2020)
+// expected-warning@+2 {{Pass-by-value of kernel functions is deprecated in SYCL 2020.}}
+#endif
+__attribute__((sycl_kernel)) void sycl_2017_single_task(Func kernelFunc) {
   kernelFunc();
 }
 
@@ -19,7 +24,7 @@ int do_nothing(int i) {
 
 // ensure both compile.
 int main() {
-  sycl_12_single_task<class sycl12>([]() {
+  sycl_2017_single_task<class sycl12>([]() {
     do_nothing(10);
   });
 
@@ -28,4 +33,7 @@ int main() {
   });
 
   return 0;
-}
+}
+#if defined(NODIAG)
+// expected-no-diagnostics
+#endif