[SYCL][Driver] Fix suggested target triple in the warning message (#4475)

The warning message emitted for deprecated target triple includes
suggested target triple to be used instead of deprecated one. Currently
it prints only architecture component of the target triple, which works
only for SPIR target architecture. Non-SPIR targets may support multiple
vendor/OS components, so users are expected to specify the full triple.
This patch fixes the warning message and suggests all components set
before deprecated `sycldevice` environment component if they are not
"unknown" (which is default and can be omitted).

Author: bader

clang/lib/Driver/Driver.cpp

@@ -925,8 +925,17 @@ void Driver::CreateOffloadingDeviceToolChains(Compilation &C,
 
           // Warn about deprecated `sycldevice` environment component.
           if (TT.getEnvironmentName() == "sycldevice") {
+            // Build a string with suggested target triple.
+            std::string SuggestedTriple = TT.getArchName().str();
+            if (TT.getOS() != llvm::Triple::UnknownOS) {
+              SuggestedTriple += '-';
+              if (TT.getVendor() != llvm::Triple::UnknownVendor)
+                SuggestedTriple += TT.getVendorName();
+              SuggestedTriple += Twine("-" + TT.getOSName()).str();
+            } else if (TT.getVendor() != llvm::Triple::UnknownVendor)
+              SuggestedTriple += Twine("-" + TT.getVendorName()).str();
             Diag(clang::diag::warn_drv_deprecated_arg)
-                << TT.str() << TT.getArchName();
+                << TT.str() << SuggestedTriple;
             // Drop environment component.
             std::string EffectiveTriple =
                 Twine(TT.getArchName() + "-" + TT.getVendorName() + "-" +

clang/test/Driver/sycl.c

@@ -28,8 +28,9 @@
 // DISABLED-NOT: "-sycl-std={{.*}}"
 // DISABLED-NOT: "-fsycl-std-layout-kernel-params"
 
-// RUN: %clangxx -fsycl -fsycl-targets=spir64-unknown-unknown-sycldevice -c %s 2>&1 | FileCheck %s --check-prefix=CHECK_WARNING
+// RUN: %clangxx -fsycl -fsycl-targets=spir64-unknown-unknown-sycldevice,nvptx64-nvidia-cuda-sycldevice -fno-sycl-libspirv -nocudalib -c %s 2>&1 | FileCheck %s --check-prefix=CHECK_WARNING
 // CHECK_WARNING: argument 'spir64-unknown-unknown-sycldevice' is deprecated, use 'spir64' instead
+// CHECK_WARNING: argument 'nvptx64-nvidia-cuda-sycldevice' is deprecated, use 'nvptx64-nvidia-cuda' instead
 
 // RUN: %clang -### -fsycl-device-only -c %s 2>&1 | FileCheck %s --check-prefix=DEFAULT
 // RUN: %clang -### -fsycl-device-only %s 2>&1 | FileCheck %s --check-prefix=DEFAULT