[libc-commits] [libc] [libc] Implement vector 'split' and 'concat' routines (PR #157537)

[Joseph Huber via libc-commits]

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@@ -61,6 +57,74 @@ using simd = T [[clang::ext_vector_type(N)]];
 template <typename T>
 using simd_mask = simd<bool, internal::native_vector_size<T>>;
 
+namespace internal {
+
+template <typename T>
+using get_as_integer_type_t = unsigned _BitInt(sizeof(T) * CHAR_BIT);
+
+template <typename T> LIBC_INLINE constexpr T poison() {
+  return __builtin_nondeterministic_value(T());
+}
+
+template <typename T, size_t N, size_t OriginalSize, size_t... Indices>
+LIBC_INLINE constexpr static cpp::simd<T, sizeof...(Indices)>
+extend(cpp::simd<T, N> x, cpp::index_sequence<Indices...>) {
+  return __builtin_shufflevector(
+      x, x, (Indices < OriginalSize ? static_cast<int>(Indices) : -1)...);
+}
+
+template <typename T, size_t N, size_t TargetSize, size_t OriginalSize>
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jhuber6 wrote:

Nevermind, renaming the function breaks everything because I remembered I wrote it this way on purpose. It'll just need to be confusing.

https://github.com/llvm/llvm-project/pull/157537