[NVPTX] Support the OpenCL generic addrspace feature by default

[frasercrmck]

As best as I can see, all NVPTX architectures support the generic address space.

I note there's a FIXME in the target's address space map about 'generic' still having to be added to the target but we haven't observed any issues with it downstream. The generic address space is mapped to the same target address space as default/private (0), but this isn't necessarily a problem for users.

[llvmbot]

@llvm/pr-subscribers-clang

Author: Fraser Cormack (frasercrmck)

Changes

As best as I can see, all NVPTX architectures support the generic address space.

I note there's a FIXME in the target's address space map about 'generic' still having to be added to the target but we haven't observed any issues with it downstream. The generic address space is mapped to the same target address space as default/private (0), but this isn't necessarily a problem for users.

---

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

2 Files Affected:

• (modified) clang/lib/Basic/Targets/NVPTX.h (+2)
• (modified) clang/test/Misc/nvptx.languageOptsOpenCL.cl (+8)

diff --git a/clang/lib/Basic/Targets/NVPTX.h b/clang/lib/Basic/Targets/NVPTX.h
index dc1ecc30980b7..fbb46001b0f90 100644
--- a/clang/lib/Basic/Targets/NVPTX.h
+++ b/clang/lib/Basic/Targets/NVPTX.h
@@ -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;
   }
 
   const llvm::omp::GV &getGridValue() const override {
diff --git a/clang/test/Misc/nvptx.languageOptsOpenCL.cl b/clang/test/Misc/nvptx.languageOptsOpenCL.cl
index f479dddffb3ab..2610cfafc257b 100644
--- a/clang/test/Misc/nvptx.languageOptsOpenCL.cl
+++ b/clang/test/Misc/nvptx.languageOptsOpenCL.cl
@@ -132,3 +132,11 @@
 #pragma OPENCL EXTENSION cl_khr_subgroups: enable
 // expected-warning@-1{{unsupported OpenCL extension 'cl_khr_subgroups' - ignoring}}
 
+#if (__OPENCL_C_VERSION__ >= 300)
+#ifndef __opencl_c_generic_address_space
+#error "Missing __opencl_c_generic_address_space define"
+#else
+#error "Incorrect __opencl_c_generic_address_space define"
+#endif
+#pragma OPENCL EXTENSION __opencl_c_generic_address_space: enable
+#endif