[SYCL] Change clang toolchain local accessor check (#5408)

This PR resolves an issue raised in #5149.
It changes the the check from `IsSYCL` to `IsSYCLOffloadDevice` and limits its usage to nvptx and amdgcn.
A new test is added, to prevent regression.

Author: AidanBeltonS

clang/lib/Driver/ToolChains/Clang.cpp

@@ -5795,7 +5795,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   // Enable local accessor to shared memory pass for SYCL.
-  if (isa<BackendJobAction>(JA) && IsSYCL) {
+  if (isa<BackendJobAction>(JA) && IsSYCLOffloadDevice &&
+      (Triple.isNVPTX() || Triple.isAMDGCN())) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-sycl-enable-local-accessor");
   }

clang/test/Driver/sycl-local-accessor-opt.cpp

@@ -3,8 +3,11 @@
 // REQUIRES: clang-driver
 
 // RUN:   %clang -fsycl -### %s 2>&1 \
-// RUN:   | FileCheck -check-prefix=CHECK-NO-OPT %s
-// CHECK-NO-OPT-NOT: "-sycl-enable-local-accessor"
+// RUN:   | FileCheck -check-prefix=OPT-CHECK %s
+
+// RUN:   %clang -fsycl -S -### %s 2>&1 \
+// RUN:   | FileCheck -check-prefix=OPT-CHECK %s
+// OPT-CHECK-NOT: "-sycl-enable-local-accessor"
 
 // RUN:   %clang -fsycl -fsycl-targets=nvptx64-nvidia-cuda -### %s 2>&1 \
 // RUN:   | FileCheck %s