[libcxx-commits] [libcxx] [libc++][PSTL] Add backend for forwaring to mem functions (PR #102448)

[Louis Dionne via libcxx-commits]

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@@ -49,11 +49,12 @@ struct __default_backend_tag;
 struct __libdispatch_backend_tag;
 struct __serial_backend_tag;
 struct __std_thread_backend_tag;
+struct __forward_to_mem_funcs_backend_tag;
 
 #if defined(_LIBCPP_PSTL_BACKEND_SERIAL)
 using __current_configuration = __backend_configuration<__serial_backend_tag, __default_backend_tag>;
 #elif defined(_LIBCPP_PSTL_BACKEND_STD_THREAD)
-using __current_configuration = __backend_configuration<__std_thread_backend_tag, __default_backend_tag>;
+using __current_configuration = __backend_configuration<__forward_to_mem_funcs_backend_tag, __std_thread_backend_tag, __default_backend_tag>;
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ldionne wrote:

It seems to me that we basically always want to have that "partial backend" first. When we can forward to C implementations, that should always be better than the alternative.

https://github.com/llvm/llvm-project/pull/102448