Make compat with full device_global impl.

Signed-off-by: JackAKirk <[email protected]>

Author: JackAKirk

clang/lib/CodeGen/CodeGenModule.cpp

@@ -5759,9 +5759,15 @@ LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) {
     if (Scope && Scope->isWorkGroup())
       return LangAS::sycl_local;
 
-    const RecordDecl *RD = D->getType()->getAsRecordDecl();
-    if (getTriple().isNVPTX() && RD && RD->hasAttr<SYCLDeviceGlobalAttr>() && D->getType().isConstQualified())
-      return LangAS::cuda_constant;
+    if (getTriple().isNVPTX() || getTriple().isAMDGPU()) {
+      const RecordDecl *RD = D->getType()->getAsRecordDecl();
+      if (RD && RD->hasAttr<SYCLDeviceGlobalAttr>()) {
+        clang::CXXRecordDecl *record = D->getType()->getAsCXXRecordDecl();
+        const auto *Spec = cast<ClassTemplateSpecializationDecl>(record);
+        if (Spec->getTemplateArgs().get(0).getAsType().isConstQualified())
+          return LangAS::opencl_constant;
+      }
+    }
   }
 
   if (LangOpts.SYCLIsDevice &&

sycl/test-e2e/DeviceGlobal/device_global_const.cpp

@@ -0,0 +1,31 @@
+// RUN: %{build} -o %t.out
+// RUN: %{run} %t.out
+//
+// The OpenCL GPU backends do not currently support device_global backend
+// calls.
+//
+// UNSUPPORTED: opencl && gpu
+
+#include "common.hpp"
+
+device_global<const int, TestProperties> DeviceGlobalVar;
+
+int main() {
+  queue Q;
+
+  int HostVal = 42;
+  Q.memcpy(DeviceGlobalVar, &HostVal);
+  Q.wait();
+  int OutVal = 0;
+
+  {
+    buffer<int, 1> OutBuf(&OutVal, 1);
+    Q.submit([&](handler &CGH) {
+      auto OutAcc = OutBuf.get_access<access::mode::write>(CGH);
+      CGH.single_task([=]() { OutAcc[0] = DeviceGlobalVar.get(); });
+    });
+  }
+  
+  assert(OutVal == 42 && "Read value does not match.");
+  return 0;
+}