[libcxx-commits] [libcxx] [libc++] Optimize num_get integral functions (PR #121795)

[Louis Dionne via libcxx-commits]

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@@ -116,11 +116,36 @@ template <class _VecT, class _Iter>
   }(make_index_sequence<__simd_vector_size_v<_VecT>>{});
 }
 
+// Load the first _Np elements, zero the rest
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wpsabi")
+template <class _VecT, size_t _Np, class _Iter>
+[[__nodiscard__]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _VecT __partial_load(_Iter __iter) noexcept {
+  return [=]<size_t... _LoadIndices, size_t... _ZeroIndices>(
+             index_sequence<_LoadIndices...>, index_sequence<_ZeroIndices...>) _LIBCPP_ALWAYS_INLINE noexcept {
+    return _VecT{__iter[_LoadIndices]...};
+  }(make_index_sequence<_Np>{}, make_index_sequence<__simd_vector_size_v<_VecT> - _Np>{});
+}
+
+template <class _VecT>
+[[__nodiscard__]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _VecT
+__broadcast(__simd_vector_underlying_type_t<_VecT> __val) {
+  return [&]<std::size_t... _Indices>(index_sequence<_Indices...>) {
+    return _VecT{((void)_Indices, __val)...};
+  }(make_index_sequence<__simd_vector_size_v<_VecT>>());
+}
+_LIBCPP_DIAGNOSTIC_POP
+
 template <class _Tp, size_t _Np>
 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI bool __all_of(__simd_vector<_Tp, _Np> __vec) noexcept {
   return __builtin_reduce_and(__builtin_convertvector(__vec, __simd_vector<bool, _Np>));
 }
 
+template <class _Tp, size_t _Np>
+[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI bool __none_of(__simd_vector<_Tp, _Np> __vec) noexcept {
+  return !__builtin_reduce_or(__vec);
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ldionne wrote:

I find it confusing that we use `__builtin_convertvector` for `__all_of` but not for `__none_of`. IMO we should either use it in both places or in neither. From our discussion it looks like it's needed in both cases.

https://github.com/llvm/llvm-project/pull/121795