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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:44:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:44:51 +0000 |
commit | 9e3c08db40b8916968b9f30096c7be3f00ce9647 (patch) | |
tree | a68f146d7fa01f0134297619fbe7e33db084e0aa /third_party/highway/hwy/contrib/algo/copy-inl.h | |
parent | Initial commit. (diff) | |
download | thunderbird-upstream.tar.xz thunderbird-upstream.zip |
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/highway/hwy/contrib/algo/copy-inl.h')
-rw-r--r-- | third_party/highway/hwy/contrib/algo/copy-inl.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/third_party/highway/hwy/contrib/algo/copy-inl.h b/third_party/highway/hwy/contrib/algo/copy-inl.h new file mode 100644 index 0000000000..033cf8a626 --- /dev/null +++ b/third_party/highway/hwy/contrib/algo/copy-inl.h @@ -0,0 +1,136 @@ +// Copyright 2022 Google LLC +// SPDX-License-Identifier: Apache-2.0 +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Per-target include guard +#if defined(HIGHWAY_HWY_CONTRIB_ALGO_COPY_INL_H_) == \ + defined(HWY_TARGET_TOGGLE) +#ifdef HIGHWAY_HWY_CONTRIB_ALGO_COPY_INL_H_ +#undef HIGHWAY_HWY_CONTRIB_ALGO_COPY_INL_H_ +#else +#define HIGHWAY_HWY_CONTRIB_ALGO_COPY_INL_H_ +#endif + +#include "hwy/highway.h" + +HWY_BEFORE_NAMESPACE(); +namespace hwy { +namespace HWY_NAMESPACE { + +// These functions avoid having to write a loop plus remainder handling in the +// (unfortunately still common) case where arrays are not aligned/padded. If the +// inputs are known to be aligned/padded, it is more efficient to write a single +// loop using Load(). We do not provide a CopyAlignedPadded because it +// would be more verbose than such a loop. + +// Fills `to`[0, `count`) with `value`. +template <class D, typename T = TFromD<D>> +void Fill(D d, T value, size_t count, T* HWY_RESTRICT to) { + const size_t N = Lanes(d); + const Vec<D> v = Set(d, value); + + size_t idx = 0; + for (; idx + N <= count; idx += N) { + StoreU(v, d, to + idx); + } + + // `count` was a multiple of the vector length `N`: already done. + if (HWY_UNLIKELY(idx == count)) return; + + const size_t remaining = count - idx; + HWY_DASSERT(0 != remaining && remaining < N); + SafeFillN(remaining, value, d, to + idx); +} + +// Copies `from`[0, `count`) to `to`, which must not overlap `from`. +template <class D, typename T = TFromD<D>> +void Copy(D d, const T* HWY_RESTRICT from, size_t count, T* HWY_RESTRICT to) { + const size_t N = Lanes(d); + + size_t idx = 0; + for (; idx + N <= count; idx += N) { + const Vec<D> v = LoadU(d, from + idx); + StoreU(v, d, to + idx); + } + + // `count` was a multiple of the vector length `N`: already done. + if (HWY_UNLIKELY(idx == count)) return; + + const size_t remaining = count - idx; + HWY_DASSERT(0 != remaining && remaining < N); + SafeCopyN(remaining, d, from + idx, to + idx); +} + +// For idx in [0, count) in ascending order, appends `from[idx]` to `to` if the +// corresponding mask element of `func(d, v)` is true. Returns the STL-style end +// of the newly written elements in `to`. +// +// `func` is either a functor with a templated operator()(d, v) returning a +// mask, or a generic lambda if using C++14. Due to apparent limitations of +// Clang on Windows, it is currently necessary to add HWY_ATTR before the +// opening { of the lambda to avoid errors about "function .. requires target". +// +// NOTE: this is only supported for 16-, 32- or 64-bit types. +// NOTE: Func may be called a second time for elements it has already seen, but +// these elements will not be written to `to` again. +template <class D, class Func, typename T = TFromD<D>> +T* CopyIf(D d, const T* HWY_RESTRICT from, size_t count, T* HWY_RESTRICT to, + const Func& func) { + const size_t N = Lanes(d); + + size_t idx = 0; + for (; idx + N <= count; idx += N) { + const Vec<D> v = LoadU(d, from + idx); + to += CompressBlendedStore(v, func(d, v), d, to); + } + + // `count` was a multiple of the vector length `N`: already done. + if (HWY_UNLIKELY(idx == count)) return to; + +#if HWY_MEM_OPS_MIGHT_FAULT + // Proceed one by one. + const CappedTag<T, 1> d1; + for (; idx < count; ++idx) { + using V1 = Vec<decltype(d1)>; + // Workaround for -Waggressive-loop-optimizations on GCC 8 + // (iteration 2305843009213693951 invokes undefined behavior for T=i64) + const uintptr_t addr = reinterpret_cast<uintptr_t>(from); + const T* HWY_RESTRICT from_idx = + reinterpret_cast<const T * HWY_RESTRICT>(addr + (idx * sizeof(T))); + const V1 v = LoadU(d1, from_idx); + // Avoid storing to `to` unless we know it should be kept - otherwise, we + // might overrun the end if it was allocated for the exact count. + if (CountTrue(d1, func(d1, v)) == 0) continue; + StoreU(v, d1, to); + to += 1; + } +#else + // Start index of the last unaligned whole vector, ending at the array end. + const size_t last = count - N; + // Number of elements before `from` or already written. + const size_t invalid = idx - last; + HWY_DASSERT(0 != invalid && invalid < N); + const Mask<D> mask = Not(FirstN(d, invalid)); + const Vec<D> v = MaskedLoad(mask, d, from + last); + to += CompressBlendedStore(v, And(mask, func(d, v)), d, to); +#endif + return to; +} + +// NOLINTNEXTLINE(google-readability-namespace-comments) +} // namespace HWY_NAMESPACE +} // namespace hwy +HWY_AFTER_NAMESPACE(); + +#endif // HIGHWAY_HWY_CONTRIB_ALGO_COPY_INL_H_ |