[clang] [NVPTX] Support the OpenCL generic addrspace feature by default (PR #137940)

[Sven van Haastregt via cfe-commits]

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@@ -170,6 +170,8 @@ class LLVM_LIBRARY_VISIBILITY NVPTXTargetInfo : public TargetInfo {
     Opts["cl_khr_global_int32_extended_atomics"] = true;
     Opts["cl_khr_local_int32_base_atomics"] = true;
     Opts["cl_khr_local_int32_extended_atomics"] = true;
+
+    Opts["__opencl_c_generic_address_space"] = true;
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svenvh wrote:

This is target specific, so I agree with @frasercrmck 's reasoning and would say it's fine as is.

https://github.com/llvm/llvm-project/pull/137940