[clang] [Clang] Fix 'gpuintrin.h' match when included with no arch set (PR #129927)

[Joseph Huber via cfe-commits]

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@@ -179,8 +179,10 @@ __gpu_shuffle_idx_u64(uint64_t __lane_mask, uint32_t __idx, uint64_t __x,
 _DEFAULT_FN_ATTRS static __inline__ uint64_t
 __gpu_match_any_u32(uint64_t __lane_mask, uint32_t __x) {
   // Newer targets can use the dedicated CUDA support.
-  if (__CUDA_ARCH__ >= 700 || __nvvm_reflect("__CUDA_ARCH") >= 700)
+#if __CUDA_ARCH__ >= 700
+  if (__nvvm_reflect("__CUDA_ARCH") >= 700)
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jhuber6 wrote:

Probably just because I forgot to but it was a no-op so I didn't notice.

And yeah, I wish there was a way to let `nvvm_reflect` call these without the incurring the wrath of the compiler. You can spoof some target attributes but that's always broken when inlined.

https://github.com/llvm/llvm-project/pull/129927