[clang] [llvm] [SPIRV] GPU intrinsics (PR #131190)

[Matt Arsenault via llvm-commits]

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@@ -2861,6 +2861,69 @@ def int_experimental_convergence_anchor
 def int_experimental_convergence_loop
   : DefaultAttrsIntrinsic<[llvm_token_ty], [], [IntrNoMem, IntrConvergent]>;
 
+//===------- GPU Intrinsics -----------------------------------------------===//
+
+class GPUIntrinsic<LLVMType ret_type, string name>
+  : DefaultAttrsIntrinsic<[ret_type],
+                          [],
+                          [NoUndef<RetIndex>, IntrNoMem, IntrSpeculatable]>,
+                          ClangBuiltin<name>;
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arsenm wrote:

https://godbolt.org/z/9Gv4jsW3n even the undecorated fake.use infers everything 

https://github.com/llvm/llvm-project/pull/131190