mirror of
https://github.com/matrix-construct/construct
synced 2024-11-05 05:18:54 +01:00
65 lines
1.8 KiB
C++
65 lines
1.8 KiB
C++
// The Construct
|
|
//
|
|
// Copyright (C) The Construct Developers, Authors & Contributors
|
|
// Copyright (C) 2016-2020 Jason Volk <jason@zemos.net>
|
|
//
|
|
// Permission to use, copy, modify, and/or distribute this software for any
|
|
// purpose with or without fee is hereby granted, provided that the above
|
|
// copyright notice and this permission notice is present in all copies. The
|
|
// full license for this software is available in the LICENSE file.
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_SIMD_GATHER_H
|
|
|
|
namespace ircd::simd
|
|
{
|
|
template<int scale = 1,
|
|
class value,
|
|
class index_vector,
|
|
class value_vector>
|
|
value_vector gather(const value *, const index_vector, const u64, value_vector) noexcept;
|
|
}
|
|
|
|
/// Gather values from memory locations into the returned vector. This template
|
|
/// emits vpgather on skylake and later. On broadwell and haswell and earlier
|
|
/// this template will not emit any vpgather by default.
|
|
///
|
|
/// Each lane in the index vector corresponds to each lane in the return vector.
|
|
/// Each bit in the mask corresponds to each lane as well.
|
|
/// The default values for each lane are provided in the last argument.
|
|
///
|
|
template<int scale,
|
|
class value,
|
|
class index_vector,
|
|
class value_vector>
|
|
inline value_vector
|
|
ircd::simd::gather(const value *const __restrict__ base,
|
|
const index_vector index,
|
|
const u64 mask,
|
|
value_vector ret)
|
|
noexcept
|
|
{
|
|
static_assert
|
|
(
|
|
lanes<index_vector>() == lanes<value_vector>()
|
|
);
|
|
|
|
auto *const out
|
|
{
|
|
reinterpret_cast<lane_type<value_vector> *>(&ret)
|
|
};
|
|
|
|
const auto *const idx
|
|
{
|
|
reinterpret_cast<const lane_type<index_vector> *>(&index)
|
|
};
|
|
|
|
#if defined(__AVX2__)
|
|
#pragma clang loop unroll(disable)
|
|
#endif
|
|
for(size_t i(0); i < lanes<index_vector>(); ++i)
|
|
if(mask & (1UL << i))
|
|
out[i] = base[idx[i] * scale];
|
|
|
|
return ret;
|
|
}
|