[HIP] Diagnose -fopenmp-targets for HIP programs

[yaxunl]

Summary

Diagnose -fopenmp-targets for HIP programs since dual HIP and OpenMP offloading in the same compilation
is currently not supported by HIP toolchain.

[tra]

clang/lib/Driver/Driver.cpp

704

I think "unsupported" here is a bit misleading. We need something along the lines of "option X can't be used with option Y".

I think err_drv_argument_not_allowed_with might be a better choice.

[yaxunl]

clang/lib/Driver/Driver.cpp

704

That is for two conflicting options. However, HIP may be specified by input file extension instead of -x option. Another issue is that this is unsupported option for HIP, not option argument.

How about

unsupported option '%1' for HIP language mode

[tra]

clang/lib/Driver/Driver.cpp

704

SGTM.

[yaxunl]

revise diag message

clang/lib/Driver/Driver.cpp

     }
     C.addOffloadDeviceToolChain(CudaTC.get(), OFK);
   } else if (IsHIP) {
+    if (auto *OMPTargetArg =
+            C.getInputArgs().getLastArg(options::OPT_fopenmp_targets_EQ)) {
+      Diag(clang::diag::err_drv_unsupported_opt) << OMPTargetArg->getSpelling();
+      return;
+    }
     const ToolChain *HostTC = C.getSingleOffloadToolChain<Action::OFK_Host>();
     const llvm::Triple &HostTriple = HostTC->getTriple();
     auto OFK = Action::OFK_HIP;

clang/test/Driver/hip-options.hip

 // THINLTO-NOT: clang{{.*}}" "-triple" "amdgcn-amd-amdhsa" {{.*}} "-fwhole-program-vtables"
 // THINLTO: clang{{.*}}" "-triple" "x86_64-unknown-linux-gnu" {{.*}} "-flto=thin" {{.*}} "-fwhole-program-vtables"
 // THINLTO-NOT: clang{{.*}}" "-triple" "amdgcn-amd-amdhsa" {{.*}} "-fwhole-program-vtables"
+
+// Check -fopenmp is allowed with HIP but -fopenmp-targets= is not allowed.
+
+// RUN: %clang -### -target x86_64-unknown-linux-gnu -nogpuinc -nogpulib \
+// RUN:   --offload-arch=gfx906 -fopenmp %s 2>&1 | FileCheck -check-prefix=OMP %s
+// OMP-NOT: clang{{.*}} "-triple" "amdgcn-amd-amdhsa" {{.*}} "-fopenmp"
+// OMP: clang{{.*}} "-triple" "x86_64-unknown-linux-gnu" {{.*}} "-fopenmp"
+
+// RUN: not %clang -target x86_64-unknown-linux-gnu -nogpuinc -nogpulib \
+// RUN:   --offload-arch=gfx906 -fopenmp -fopenmp-targets=amdgcn %s 2>&1 \
+// RUN:   | FileCheck -check-prefix=OMPTGT %s
+// OMPTGT: unsupported option '-fopenmp-targets='