[clang] [OpenMP][Clang] Add support for OMP6.1 fb_nullify and fb_preserve in need_device_ptr modifier (PR #168905)

[Zahira Ammarguellat via cfe-commits]

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@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -verify -fopenmp -fopenmp-version=61 %s
+
+void __attribute__((noinline)) device_impl(int *xp, int *&xpref, int n) {}
+
+#pragma omp declare variant(device_impl)                                       \
+    adjust_args(need_device_ptr(foo) : xp, xpref)   // expected-error{{unknown modifier in 'need_device_ptr' clause (OpenMP 6.1 or later only)}} // expected-error{{expected 'match', 'adjust_args', or 'append_args' clause on 'omp declare variant' directive}}
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zahiraam wrote:

Done.

https://github.com/llvm/llvm-project/pull/168905