Improve swizzle for arm32 - [u]int32

Author: serge-sans-paille

include/xsimd/arch/xsimd_neon.hpp

@@ -2914,6 +2914,55 @@ namespace xsimd
         {
             return vreinterpretq_s64_u64(swizzle(vreinterpretq_u64_s64(self), mask, A {}));
         }
+
+        template <class A, uint32_t V0, uint32_t V1, uint32_t V2, uint32_t V3>
+        XSIMD_INLINE batch<uint32_t, A> swizzle(batch<uint32_t, A> const& self,
+                                                batch_constant<uint32_t, A, V0, V1, V2, V3> mask,
+                                                requires_arch<neon>) noexcept
+        {
+            constexpr bool is_identity = detail::is_identity(mask);
+            constexpr bool is_dup_lo = detail::is_dup_lo(mask);
+            constexpr bool is_dup_hi = detail::is_dup_hi(mask);
+
+            XSIMD_IF_CONSTEXPR(is_identity)
+            {
+                return self;
+            }
+            XSIMD_IF_CONSTEXPR(is_dup_lo)
+            {
+                XSIMD_IF_CONSTEXPR(V0 == 0 && V1 == 1)
+                {
+                    return vreinterpretq_u32_u64(vdupq_lane_u64(vget_low_u64(vreinterpretq_u64_u32(self)), 0));
+                }
+                else
+                {
+                    return vreinterpretq_u32_u64(vdupq_lane_u64(vreinterpret_u64_u32(vrev64_u32(vget_low_u32(self))), 0));
+                }
+            }
+            XSIMD_IF_CONSTEXPR(is_dup_hi)
+            {
+                XSIMD_IF_CONSTEXPR(V0 == 2 && V1 == 3)
+                {
+                    return vreinterpretq_u32_u64(vdupq_lane_u64(vget_high_u64(vreinterpretq_u64_u32(self)), 0));
+                }
+                else
+                {
+                    return vreinterpretq_u32_u64(vdupq_lane_u64(vreinterpret_u64_u32(vrev64_u32(vget_high_u32(self))), 0));
+                }
+                return lo_all;
+            }
+            std::array<T, batch<T, A>::size> data;
+            self.store_aligned(data.data());
+            return set(batch<T, A>(), A(), data[idx]...);
+        }
+
+        template <class A, uint32_t V0, uint32_t V1>
+        XSIMD_INLINE batch<int32_t, A> swizzle(batch<int32_t, A> const& self,
+                                               batch_constant<int32_t, A, V0, V1> mask,
+                                               requires_arch<neon>) noexcept
+        {
+            return vreinterpretq_s32_u32(swizzle(vreinterpretq_u32_s32(self), mask, A {}));
+        }
     }
 
 }