[libc] [llvm] [OpenMP] Build OpenMP DeviceRTL on SPIR-V (PR #121600)

[Nick Sarnie via llvm-commits]

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@@ -157,7 +157,7 @@ RPC_ATTRS void sleep_briefly() {
     asm("nanosleep.u32 64;" ::: "memory");
 #elif defined(__AMDGPU__) && defined(RPC_TARGET_IS_GPU)
   __builtin_amdgcn_s_sleep(2);
-#elif __has_builtin(__builtin_ia32_pause)
+#elif __has_builtin(__builtin_ia32_pause) && !defined(__SPIRV__)
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sarnex wrote:

This turned out to be pretty annoying, I have a PR [here](https://github.com/llvm/llvm-project/pull/121839) that attempts to fix it, will mark it ready for review once CI passes.

https://github.com/llvm/llvm-project/pull/121600