6 files changed, 1299 insertions, 0 deletions
diff --git a/media/highway/src/hwy/contrib/algo/copy-inl.h b/media/highway/src/hwy/contrib/algo/copy-inl.h
new file mode 100644
index 0000000000..34e926a915
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/copy-inl.h
@@ -0,0 +1,138 @@
+// 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 <string.h>  // memcpy
+
+#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_
diff --git a/media/highway/src/hwy/contrib/algo/copy_test.cc b/media/highway/src/hwy/contrib/algo/copy_test.cc
new file mode 100644
index 0000000000..8e55cd5bec
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/copy_test.cc
@@ -0,0 +1,199 @@
+// 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.
+
+#include "hwy/aligned_allocator.h"
+
+// clang-format off
+#undef HWY_TARGET_INCLUDE
+#define HWY_TARGET_INCLUDE "hwy/contrib/algo/copy_test.cc"
+#include "hwy/foreach_target.h"
+
+#include "hwy/contrib/algo/copy-inl.h"
+#include "hwy/tests/test_util-inl.h"
+// clang-format on
+
+// If your project requires C++14 or later, you can ignore this and pass lambdas
+// directly to Transform, without requiring an lvalue as we do here for C++11.
+#if __cplusplus < 201402L
+#define HWY_GENERIC_LAMBDA 0
+#else
+#define HWY_GENERIC_LAMBDA 1
+#endif
+
+HWY_BEFORE_NAMESPACE();
+namespace hwy {
+namespace HWY_NAMESPACE {
+
+// Returns random integer in [0, 128), which fits in any lane type.
+template <typename T>
+T Random7Bit(RandomState& rng) {
+  return static_cast<T>(Random32(&rng) & 127);
+}
+
+// In C++14, we can instead define these as generic lambdas next to where they
+// are invoked.
+#if !HWY_GENERIC_LAMBDA
+
+struct IsOdd {
+  template <class D, class V>
+  Mask<D> operator()(D d, V v) const {
+    return TestBit(v, Set(d, TFromD<D>{1}));
+  }
+};
+
+#endif  // !HWY_GENERIC_LAMBDA
+
+// Invokes Test (e.g. TestCopyIf) with all arg combinations. T comes from
+// ForFloatTypes.
+template <class Test>
+struct ForeachCountAndMisalign {
+  template <typename T, class D>
+  HWY_NOINLINE void operator()(T /*unused*/, D d) const {
+    RandomState rng;
+    const size_t N = Lanes(d);
+    const size_t misalignments[3] = {0, N / 4, 3 * N / 5};
+
+    for (size_t count = 0; count < 2 * N; ++count) {
+      for (size_t ma : misalignments) {
+        for (size_t mb : misalignments) {
+          Test()(d, count, ma, mb, rng);
+        }
+      }
+    }
+  }
+};
+
+struct TestFill {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    using T = TFromD<D>;
+    // HWY_MAX prevents error when misalign == count == 0.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    T* expected = pa.get() + misalign_a;
+    const T value = Random7Bit<T>(rng);
+    for (size_t i = 0; i < count; ++i) {
+      expected[i] = value;
+    }
+    AlignedFreeUniquePtr<T[]> pb = AllocateAligned<T>(misalign_b + count + 1);
+    T* actual = pb.get() + misalign_b;
+
+    actual[count] = T{0};  // sentinel
+    Fill(d, value, count, actual);
+    HWY_ASSERT_EQ(T{0}, actual[count]);  // did not write past end
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected, actual, count, target_name,
+                                  __FILE__, __LINE__);
+  }
+};
+
+void TestAllFill() {
+  ForAllTypes(ForPartialVectors<ForeachCountAndMisalign<TestFill>>());
+}
+
+struct TestCopy {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    using T = TFromD<D>;
+    // Prevents error if size to allocate is zero.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    T* a = pa.get() + misalign_a;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random7Bit<T>(rng);
+    }
+    AlignedFreeUniquePtr<T[]> pb =
+        AllocateAligned<T>(HWY_MAX(1, misalign_b + count));
+    T* b = pb.get() + misalign_b;
+
+    Copy(d, a, count, b);
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, a, b, count, target_name, __FILE__,
+                                  __LINE__);
+  }
+};
+
+void TestAllCopy() {
+  ForAllTypes(ForPartialVectors<ForeachCountAndMisalign<TestCopy>>());
+}
+
+struct TestCopyIf {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    using T = TFromD<D>;
+    // Prevents error if size to allocate is zero.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    T* a = pa.get() + misalign_a;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random7Bit<T>(rng);
+    }
+    const size_t padding = Lanes(ScalableTag<T>());
+    AlignedFreeUniquePtr<T[]> pb =
+        AllocateAligned<T>(HWY_MAX(1, misalign_b + count + padding));
+    T* b = pb.get() + misalign_b;
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(HWY_MAX(1, count));
+    size_t num_odd = 0;
+    for (size_t i = 0; i < count; ++i) {
+      if (a[i] & 1) {
+        expected[num_odd++] = a[i];
+      }
+    }
+
+#if HWY_GENERIC_LAMBDA
+    const auto is_odd = [](const auto d, const auto v) HWY_ATTR {
+      return TestBit(v, Set(d, TFromD<decltype(d)>{1}));
+    };
+#else
+    const IsOdd is_odd;
+#endif
+    T* end = CopyIf(d, a, count, b, is_odd);
+    const size_t num_written = static_cast<size_t>(end - b);
+    HWY_ASSERT_EQ(num_odd, num_written);
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected.get(), b, num_odd, target_name,
+                                  __FILE__, __LINE__);
+  }
+};
+
+void TestAllCopyIf() {
+  ForUI163264(ForPartialVectors<ForeachCountAndMisalign<TestCopyIf>>());
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace hwy
+HWY_AFTER_NAMESPACE();
+
+#if HWY_ONCE
+
+namespace hwy {
+HWY_BEFORE_TEST(CopyTest);
+HWY_EXPORT_AND_TEST_P(CopyTest, TestAllFill);
+HWY_EXPORT_AND_TEST_P(CopyTest, TestAllCopy);
+HWY_EXPORT_AND_TEST_P(CopyTest, TestAllCopyIf);
+}  // namespace hwy
+
+#endif
diff --git a/media/highway/src/hwy/contrib/algo/find-inl.h b/media/highway/src/hwy/contrib/algo/find-inl.h
new file mode 100644
index 0000000000..388842e988
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/find-inl.h
@@ -0,0 +1,109 @@
+// 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_FIND_INL_H_) == \
+    defined(HWY_TARGET_TOGGLE)
+#ifdef HIGHWAY_HWY_CONTRIB_ALGO_FIND_INL_H_
+#undef HIGHWAY_HWY_CONTRIB_ALGO_FIND_INL_H_
+#else
+#define HIGHWAY_HWY_CONTRIB_ALGO_FIND_INL_H_
+#endif
+
+#include "hwy/highway.h"
+
+HWY_BEFORE_NAMESPACE();
+namespace hwy {
+namespace HWY_NAMESPACE {
+
+// Returns index of the first element equal to `value` in `in[0, count)`, or
+// `count` if not found.
+template <class D, typename T = TFromD<D>>
+size_t Find(D d, T value, const T* HWY_RESTRICT in, size_t count) {
+  const size_t N = Lanes(d);
+  const Vec<D> broadcasted = Set(d, value);
+
+  size_t i = 0;
+  for (; i + N <= count; i += N) {
+    const intptr_t pos = FindFirstTrue(d, Eq(broadcasted, LoadU(d, in + i)));
+    if (pos >= 0) return i + static_cast<size_t>(pos);
+  }
+
+  if (i != count) {
+#if HWY_MEM_OPS_MIGHT_FAULT
+    // Scan single elements.
+    const CappedTag<T, 1> d1;
+    using V1 = Vec<decltype(d1)>;
+    const V1 broadcasted1 = Set(d1, GetLane(broadcasted));
+    for (; i < count; ++i) {
+      if (AllTrue(d1, Eq(broadcasted1, LoadU(d1, in + i)))) {
+        return i;
+      }
+    }
+#else
+    const size_t remaining = count - i;
+    HWY_DASSERT(0 != remaining && remaining < N);
+    const Mask<D> mask = FirstN(d, remaining);
+    const Vec<D> v = MaskedLoad(mask, d, in + i);
+    // Apply mask so that we don't 'find' the zero-padding from MaskedLoad.
+    const intptr_t pos = FindFirstTrue(d, And(Eq(broadcasted, v), mask));
+    if (pos >= 0) return i + static_cast<size_t>(pos);
+#endif  // HWY_MEM_OPS_MIGHT_FAULT
+  }
+
+  return count;  // not found
+}
+
+// Returns index of the first element in `in[0, count)` for which `func(d, vec)`
+// returns true, otherwise `count`.
+template <class D, class Func, typename T = TFromD<D>>
+size_t FindIf(D d, const T* HWY_RESTRICT in, size_t count, const Func& func) {
+  const size_t N = Lanes(d);
+
+  size_t i = 0;
+  for (; i + N <= count; i += N) {
+    const intptr_t pos = FindFirstTrue(d, func(d, LoadU(d, in + i)));
+    if (pos >= 0) return i + static_cast<size_t>(pos);
+  }
+
+  if (i != count) {
+#if HWY_MEM_OPS_MIGHT_FAULT
+    // Scan single elements.
+    const CappedTag<T, 1> d1;
+    for (; i < count; ++i) {
+      if (AllTrue(d1, func(d1, LoadU(d1, in + i)))) {
+        return i;
+      }
+    }
+#else
+    const size_t remaining = count - i;
+    HWY_DASSERT(0 != remaining && remaining < N);
+    const Mask<D> mask = FirstN(d, remaining);
+    const Vec<D> v = MaskedLoad(mask, d, in + i);
+    // Apply mask so that we don't 'find' the zero-padding from MaskedLoad.
+    const intptr_t pos = FindFirstTrue(d, And(func(d, v), mask));
+    if (pos >= 0) return i + static_cast<size_t>(pos);
+#endif  // HWY_MEM_OPS_MIGHT_FAULT
+  }
+
+  return count;  // not found
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace hwy
+HWY_AFTER_NAMESPACE();
+
+#endif  // HIGHWAY_HWY_CONTRIB_ALGO_FIND_INL_H_
diff --git a/media/highway/src/hwy/contrib/algo/find_test.cc b/media/highway/src/hwy/contrib/algo/find_test.cc
new file mode 100644
index 0000000000..8caf7e1512
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/find_test.cc
@@ -0,0 +1,219 @@
+// 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.
+
+#include <algorithm>
+#include <vector>
+
+#include "hwy/aligned_allocator.h"
+#include "hwy/base.h"
+#include "hwy/print.h"
+
+// clang-format off
+#undef HWY_TARGET_INCLUDE
+#define HWY_TARGET_INCLUDE "hwy/contrib/algo/find_test.cc"
+#include "hwy/foreach_target.h"
+
+#include "hwy/contrib/algo/find-inl.h"
+#include "hwy/tests/test_util-inl.h"
+// clang-format on
+
+// If your project requires C++14 or later, you can ignore this and pass lambdas
+// directly to FindIf, without requiring an lvalue as we do here for C++11.
+#if __cplusplus < 201402L
+#define HWY_GENERIC_LAMBDA 0
+#else
+#define HWY_GENERIC_LAMBDA 1
+#endif
+
+HWY_BEFORE_NAMESPACE();
+namespace hwy {
+namespace HWY_NAMESPACE {
+
+// Returns random number in [-8, 8) - we use knowledge of the range to Find()
+// values we know are not present.
+template <typename T>
+T Random(RandomState& rng) {
+  const int32_t bits = static_cast<int32_t>(Random32(&rng)) & 1023;
+  const double val = (bits - 512) / 64.0;
+  // Clamp negative to zero for unsigned types.
+  return static_cast<T>(HWY_MAX(hwy::LowestValue<T>(), val));
+}
+
+// In C++14, we can instead define these as generic lambdas next to where they
+// are invoked.
+#if !HWY_GENERIC_LAMBDA
+
+class GreaterThan {
+ public:
+  GreaterThan(int val) : val_(val) {}
+  template <class D, class V>
+  Mask<D> operator()(D d, V v) const {
+    return Gt(v, Set(d, static_cast<TFromD<D>>(val_)));
+  }
+
+ private:
+  int val_;
+};
+
+#endif  // !HWY_GENERIC_LAMBDA
+
+// Invokes Test (e.g. TestFind) with all arg combinations.
+template <class Test>
+struct ForeachCountAndMisalign {
+  template <typename T, class D>
+  HWY_NOINLINE void operator()(T /*unused*/, D d) const {
+    RandomState rng;
+    const size_t N = Lanes(d);
+    const size_t misalignments[3] = {0, N / 4, 3 * N / 5};
+
+    // Find() checks 8 vectors at a time, so we want to cover a fairly large
+    // range without oversampling (checking every possible count).
+    std::vector<size_t> counts(AdjustedReps(512));
+    for (size_t& count : counts) {
+      count = static_cast<size_t>(rng()) % (16 * N + 1);
+    }
+    counts[0] = 0;  // ensure we test count=0.
+
+    for (size_t count : counts) {
+      for (size_t m : misalignments) {
+        Test()(d, count, m, rng);
+      }
+    }
+  }
+};
+
+struct TestFind {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign, RandomState& rng) {
+    using T = TFromD<D>;
+    // Must allocate at least one even if count is zero.
+    AlignedFreeUniquePtr<T[]> storage =
+        AllocateAligned<T>(HWY_MAX(1, misalign + count));
+    T* in = storage.get() + misalign;
+    for (size_t i = 0; i < count; ++i) {
+      in[i] = Random<T>(rng);
+    }
+
+    // For each position, search for that element (which we know is there)
+    for (size_t pos = 0; pos < count; ++pos) {
+      const size_t actual = Find(d, in[pos], in, count);
+
+      // We may have found an earlier occurrence of the same value; ensure the
+      // value is the same, and that it is the first.
+      if (!IsEqual(in[pos], in[actual])) {
+        fprintf(stderr, "%s count %d, found %.15f at %d but wanted %.15f\n",
+                hwy::TypeName(T(), Lanes(d)).c_str(), static_cast<int>(count),
+                static_cast<double>(in[actual]), static_cast<int>(actual),
+                static_cast<double>(in[pos]));
+        HWY_ASSERT(false);
+      }
+      for (size_t i = 0; i < actual; ++i) {
+        if (IsEqual(in[i], in[pos])) {
+          fprintf(stderr, "%s count %d, found %f at %d but Find returned %d\n",
+                  hwy::TypeName(T(), Lanes(d)).c_str(), static_cast<int>(count),
+                  static_cast<double>(in[i]), static_cast<int>(i),
+                  static_cast<int>(actual));
+          HWY_ASSERT(false);
+        }
+      }
+    }
+
+    // Also search for values we know not to be present (out of range)
+    HWY_ASSERT_EQ(count, Find(d, T{9}, in, count));
+    HWY_ASSERT_EQ(count, Find(d, static_cast<T>(-9), in, count));
+  }
+};
+
+void TestAllFind() {
+  ForAllTypes(ForPartialVectors<ForeachCountAndMisalign<TestFind>>());
+}
+
+struct TestFindIf {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign, RandomState& rng) {
+    using T = TFromD<D>;
+    using TI = MakeSigned<T>;
+    // Must allocate at least one even if count is zero.
+    AlignedFreeUniquePtr<T[]> storage =
+        AllocateAligned<T>(HWY_MAX(1, misalign + count));
+    T* in = storage.get() + misalign;
+    for (size_t i = 0; i < count; ++i) {
+      in[i] = Random<T>(rng);
+      HWY_ASSERT(in[i] < 8);
+      HWY_ASSERT(!hwy::IsSigned<T>() || static_cast<TI>(in[i]) >= -8);
+    }
+
+    bool found_any = false;
+    bool not_found_any = false;
+
+    // unsigned T would be promoted to signed and compare greater than any
+    // negative val, whereas Set() would just cast to an unsigned value and the
+    // comparison remains unsigned, so avoid negative numbers there.
+    const int min_val = IsSigned<T>() ? -9 : 0;
+    // Includes out-of-range value 9 to test the not-found path.
+    for (int val = min_val; val <= 9; ++val) {
+#if HWY_GENERIC_LAMBDA
+      const auto greater = [val](const auto d, const auto v) HWY_ATTR {
+        return Gt(v, Set(d, static_cast<T>(val)));
+      };
+#else
+      const GreaterThan greater(val);
+#endif
+      const size_t actual = FindIf(d, in, count, greater);
+      found_any |= actual < count;
+      not_found_any |= actual == count;
+
+      const auto pos = std::find_if(
+          in, in + count, [val](T x) { return x > static_cast<T>(val); });
+      // Convert returned iterator to index.
+      const size_t expected = static_cast<size_t>(pos - in);
+      if (expected != actual) {
+        fprintf(stderr, "%s count %d val %d, expected %d actual %d\n",
+                hwy::TypeName(T(), Lanes(d)).c_str(), static_cast<int>(count),
+                val, static_cast<int>(expected), static_cast<int>(actual));
+        hwy::detail::PrintArray(hwy::detail::MakeTypeInfo<T>(), "in", in, count,
+                                0, count);
+        HWY_ASSERT(false);
+      }
+    }
+
+    // We will always not-find something due to val=9.
+    HWY_ASSERT(not_found_any);
+    // We'll find something unless the input is empty or {0} - because 0 > i
+    // is false for all i=[0,9].
+    if (count != 0 && in[0] != 0) {
+      HWY_ASSERT(found_any);
+    }
+  }
+};
+
+void TestAllFindIf() {
+  ForAllTypes(ForPartialVectors<ForeachCountAndMisalign<TestFindIf>>());
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace hwy
+HWY_AFTER_NAMESPACE();
+
+#if HWY_ONCE
+
+namespace hwy {
+HWY_BEFORE_TEST(FindTest);
+HWY_EXPORT_AND_TEST_P(FindTest, TestAllFind);
+HWY_EXPORT_AND_TEST_P(FindTest, TestAllFindIf);
+}  // namespace hwy
+
+#endif
diff --git a/media/highway/src/hwy/contrib/algo/transform-inl.h b/media/highway/src/hwy/contrib/algo/transform-inl.h
new file mode 100644
index 0000000000..3e830acb47
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/transform-inl.h
@@ -0,0 +1,262 @@
+// 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_TRANSFORM_INL_H_) == \
+    defined(HWY_TARGET_TOGGLE)
+#ifdef HIGHWAY_HWY_CONTRIB_ALGO_TRANSFORM_INL_H_
+#undef HIGHWAY_HWY_CONTRIB_ALGO_TRANSFORM_INL_H_
+#else
+#define HIGHWAY_HWY_CONTRIB_ALGO_TRANSFORM_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 TransformAlignedPadded because it
+// would be more verbose than such a loop.
+//
+// Func is either a functor with a templated operator()(d, v[, v1[, v2]]), 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 "always_inline function .. requires target".
+//
+// If HWY_MEM_OPS_MIGHT_FAULT, we use scalar code instead of masking. Otherwise,
+// we used `MaskedLoad` and `BlendedStore` to read/write the final partial
+// vector.
+
+// Fills `out[0, count)` with the vectors returned by `func(d, index_vec)`,
+// where `index_vec` is `Vec<RebindToUnsigned<D>>`. On the first call to `func`,
+// the value of its lane i is i, and increases by `Lanes(d)` after every call.
+// Note that some of these indices may be `>= count`, but the elements that
+// `func` returns in those lanes will not be written to `out`.
+template <class D, class Func, typename T = TFromD<D>>
+void Generate(D d, T* HWY_RESTRICT out, size_t count, const Func& func) {
+  const RebindToUnsigned<D> du;
+  using TU = TFromD<decltype(du)>;
+  const size_t N = Lanes(d);
+
+  size_t idx = 0;
+  Vec<decltype(du)> vidx = Iota(du, 0);
+  for (; idx + N <= count; idx += N) {
+    StoreU(func(d, vidx), d, out + idx);
+    vidx = Add(vidx, Set(du, static_cast<TU>(N)));
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  const RebindToUnsigned<decltype(d1)> du1;
+  for (; idx < count; ++idx) {
+    StoreU(func(d1, Set(du1, static_cast<TU>(idx))), d1, out + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  BlendedStore(func(d, vidx), mask, d, out + idx);
+#endif
+}
+
+// Replaces `inout[idx]` with `func(d, inout[idx])`. Example usage: multiplying
+// array elements by a constant.
+template <class D, class Func, typename T = TFromD<D>>
+void Transform(D d, T* HWY_RESTRICT inout, size_t count, 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, inout + idx);
+    StoreU(func(d, v), d, inout + idx);
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  for (; idx < count; ++idx) {
+    using V1 = Vec<decltype(d1)>;
+    const V1 v = LoadU(d1, inout + idx);
+    StoreU(func(d1, v), d1, inout + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  const Vec<D> v = MaskedLoad(mask, d, inout + idx);
+  BlendedStore(func(d, v), mask, d, inout + idx);
+#endif
+}
+
+// Replaces `inout[idx]` with `func(d, inout[idx], in1[idx])`. Example usage:
+// multiplying array elements by those of another array.
+template <class D, class Func, typename T = TFromD<D>>
+void Transform1(D d, T* HWY_RESTRICT inout, size_t count,
+                const T* HWY_RESTRICT in1, 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, inout + idx);
+    const Vec<D> v1 = LoadU(d, in1 + idx);
+    StoreU(func(d, v, v1), d, inout + idx);
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  for (; idx < count; ++idx) {
+    using V1 = Vec<decltype(d1)>;
+    const V1 v = LoadU(d1, inout + idx);
+    const V1 v1 = LoadU(d1, in1 + idx);
+    StoreU(func(d1, v, v1), d1, inout + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  const Vec<D> v = MaskedLoad(mask, d, inout + idx);
+  const Vec<D> v1 = MaskedLoad(mask, d, in1 + idx);
+  BlendedStore(func(d, v, v1), mask, d, inout + idx);
+#endif
+}
+
+// Replaces `inout[idx]` with `func(d, inout[idx], in1[idx], in2[idx])`. Example
+// usage: FMA of elements from three arrays, stored into the first array.
+template <class D, class Func, typename T = TFromD<D>>
+void Transform2(D d, T* HWY_RESTRICT inout, size_t count,
+                const T* HWY_RESTRICT in1, const T* HWY_RESTRICT in2,
+                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, inout + idx);
+    const Vec<D> v1 = LoadU(d, in1 + idx);
+    const Vec<D> v2 = LoadU(d, in2 + idx);
+    StoreU(func(d, v, v1, v2), d, inout + idx);
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  for (; idx < count; ++idx) {
+    using V1 = Vec<decltype(d1)>;
+    const V1 v = LoadU(d1, inout + idx);
+    const V1 v1 = LoadU(d1, in1 + idx);
+    const V1 v2 = LoadU(d1, in2 + idx);
+    StoreU(func(d1, v, v1, v2), d1, inout + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  const Vec<D> v = MaskedLoad(mask, d, inout + idx);
+  const Vec<D> v1 = MaskedLoad(mask, d, in1 + idx);
+  const Vec<D> v2 = MaskedLoad(mask, d, in2 + idx);
+  BlendedStore(func(d, v, v1, v2), mask, d, inout + idx);
+#endif
+}
+
+template <class D, typename T = TFromD<D>>
+void Replace(D d, T* HWY_RESTRICT inout, size_t count, T new_t, T old_t) {
+  const size_t N = Lanes(d);
+  const Vec<D> old_v = Set(d, old_t);
+  const Vec<D> new_v = Set(d, new_t);
+
+  size_t idx = 0;
+  for (; idx + N <= count; idx += N) {
+    Vec<D> v = LoadU(d, inout + idx);
+    StoreU(IfThenElse(Eq(v, old_v), new_v, v), d, inout + idx);
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  const Vec<decltype(d1)> old_v1 = Set(d1, old_t);
+  const Vec<decltype(d1)> new_v1 = Set(d1, new_t);
+  for (; idx < count; ++idx) {
+    using V1 = Vec<decltype(d1)>;
+    const V1 v1 = LoadU(d1, inout + idx);
+    StoreU(IfThenElse(Eq(v1, old_v1), new_v1, v1), d1, inout + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  const Vec<D> v = MaskedLoad(mask, d, inout + idx);
+  BlendedStore(IfThenElse(Eq(v, old_v), new_v, v), mask, d, inout + idx);
+#endif
+}
+
+template <class D, class Func, typename T = TFromD<D>>
+void ReplaceIf(D d, T* HWY_RESTRICT inout, size_t count, T new_t,
+               const Func& func) {
+  const size_t N = Lanes(d);
+  const Vec<D> new_v = Set(d, new_t);
+
+  size_t idx = 0;
+  for (; idx + N <= count; idx += N) {
+    Vec<D> v = LoadU(d, inout + idx);
+    StoreU(IfThenElse(func(d, v), new_v, v), d, inout + idx);
+  }
+
+  // `count` was a multiple of the vector length `N`: already done.
+  if (HWY_UNLIKELY(idx == count)) return;
+
+#if HWY_MEM_OPS_MIGHT_FAULT
+  // Proceed one by one.
+  const CappedTag<T, 1> d1;
+  const Vec<decltype(d1)> new_v1 = Set(d1, new_t);
+  for (; idx < count; ++idx) {
+    using V1 = Vec<decltype(d1)>;
+    const V1 v = LoadU(d1, inout + idx);
+    StoreU(IfThenElse(func(d1, v), new_v1, v), d1, inout + idx);
+  }
+#else
+  const size_t remaining = count - idx;
+  HWY_DASSERT(0 != remaining && remaining < N);
+  const Mask<D> mask = FirstN(d, remaining);
+  const Vec<D> v = MaskedLoad(mask, d, inout + idx);
+  BlendedStore(IfThenElse(func(d, v), new_v, v), mask, d, inout + idx);
+#endif
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace hwy
+HWY_AFTER_NAMESPACE();
+
+#endif  // HIGHWAY_HWY_CONTRIB_ALGO_TRANSFORM_INL_H_
diff --git a/media/highway/src/hwy/contrib/algo/transform_test.cc b/media/highway/src/hwy/contrib/algo/transform_test.cc
new file mode 100644
index 0000000000..52373cca6c
--- /dev/null
+++ b/media/highway/src/hwy/contrib/algo/transform_test.cc
@@ -0,0 +1,372 @@
+// 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.
+
+#include <string.h>
+
+#include "hwy/aligned_allocator.h"
+
+// clang-format off
+#undef HWY_TARGET_INCLUDE
+#define HWY_TARGET_INCLUDE "hwy/contrib/algo/transform_test.cc"
+#include "hwy/foreach_target.h"
+
+#include "hwy/contrib/algo/transform-inl.h"
+#include "hwy/tests/test_util-inl.h"
+// clang-format on
+
+// If your project requires C++14 or later, you can ignore this and pass lambdas
+// directly to Transform, without requiring an lvalue as we do here for C++11.
+#if __cplusplus < 201402L
+#define HWY_GENERIC_LAMBDA 0
+#else
+#define HWY_GENERIC_LAMBDA 1
+#endif
+
+HWY_BEFORE_NAMESPACE();
+namespace hwy {
+namespace HWY_NAMESPACE {
+
+template <typename T>
+T Alpha() {
+  return static_cast<T>(1.5);  // arbitrary scalar
+}
+
+// Returns random floating-point number in [-8, 8) to ensure computations do
+// not exceed float32 precision.
+template <typename T>
+T Random(RandomState& rng) {
+  const int32_t bits = static_cast<int32_t>(Random32(&rng)) & 1023;
+  const double val = (bits - 512) / 64.0;
+  // Clamp negative to zero for unsigned types.
+  return static_cast<T>(HWY_MAX(hwy::LowestValue<T>(), val));
+}
+
+// SCAL, AXPY names are from BLAS.
+template <typename T>
+HWY_NOINLINE void SimpleSCAL(const T* x, T* out, size_t count) {
+  for (size_t i = 0; i < count; ++i) {
+    out[i] = Alpha<T>() * x[i];
+  }
+}
+
+template <typename T>
+HWY_NOINLINE void SimpleAXPY(const T* x, const T* y, T* out, size_t count) {
+  for (size_t i = 0; i < count; ++i) {
+    out[i] = Alpha<T>() * x[i] + y[i];
+  }
+}
+
+template <typename T>
+HWY_NOINLINE void SimpleFMA4(const T* x, const T* y, const T* z, T* out,
+                             size_t count) {
+  for (size_t i = 0; i < count; ++i) {
+    out[i] = x[i] * y[i] + z[i];
+  }
+}
+
+// In C++14, we can instead define these as generic lambdas next to where they
+// are invoked.
+#if !HWY_GENERIC_LAMBDA
+
+// Generator that returns even numbers by doubling the output indices.
+struct Gen2 {
+  template <class D, class VU>
+  Vec<D> operator()(D d, VU vidx) const {
+    return BitCast(d, Add(vidx, vidx));
+  }
+};
+
+struct SCAL {
+  template <class D, class V>
+  Vec<D> operator()(D d, V v) const {
+    using T = TFromD<D>;
+    return Mul(Set(d, Alpha<T>()), v);
+  }
+};
+
+struct AXPY {
+  template <class D, class V>
+  Vec<D> operator()(D d, V v, V v1) const {
+    using T = TFromD<D>;
+    return MulAdd(Set(d, Alpha<T>()), v, v1);
+  }
+};
+
+struct FMA4 {
+  template <class D, class V>
+  Vec<D> operator()(D /*d*/, V v, V v1, V v2) const {
+    return MulAdd(v, v1, v2);
+  }
+};
+
+#endif  // !HWY_GENERIC_LAMBDA
+
+// Invokes Test (e.g. TestTransform1) with all arg combinations. T comes from
+// ForFloatTypes.
+template <class Test>
+struct ForeachCountAndMisalign {
+  template <typename T, class D>
+  HWY_NOINLINE void operator()(T /*unused*/, D d) const {
+    RandomState rng;
+    const size_t N = Lanes(d);
+    const size_t misalignments[3] = {0, N / 4, 3 * N / 5};
+
+    for (size_t count = 0; count < 2 * N; ++count) {
+      for (size_t ma : misalignments) {
+        for (size_t mb : misalignments) {
+          Test()(d, count, ma, mb, rng);
+        }
+      }
+    }
+  }
+};
+
+// Output-only, no loads
+struct TestGenerate {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t /*misalign_b*/,
+                  RandomState& /*rng*/) {
+    using T = TFromD<D>;
+    AlignedFreeUniquePtr<T[]> pa = AllocateAligned<T>(misalign_a + count + 1);
+    T* actual = pa.get() + misalign_a;
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(HWY_MAX(1, count));
+    for (size_t i = 0; i < count; ++i) {
+      expected[i] = static_cast<T>(2 * i);
+    }
+
+    // TODO(janwas): can we update the apply_to in HWY_PUSH_ATTRIBUTES so that
+    // the attribute also applies to lambdas? If so, remove HWY_ATTR.
+#if HWY_GENERIC_LAMBDA
+    const auto gen2 = [](const auto d, const auto vidx)
+                          HWY_ATTR { return BitCast(d, Add(vidx, vidx)); };
+#else
+    const Gen2 gen2;
+#endif
+    actual[count] = T{0};  // sentinel
+    Generate(d, actual, count, gen2);
+    HWY_ASSERT_EQ(T{0}, actual[count]);  // did not write past end
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected.get(), actual, count,
+                                  target_name, __FILE__, __LINE__);
+  }
+};
+
+// Zero extra input arrays
+struct TestTransform {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    if (misalign_b != 0) return;
+    using T = TFromD<D>;
+    // Prevents error if size to allocate is zero.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    T* a = pa.get() + misalign_a;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random<T>(rng);
+    }
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(HWY_MAX(1, count));
+    SimpleSCAL(a, expected.get(), count);
+
+    // TODO(janwas): can we update the apply_to in HWY_PUSH_ATTRIBUTES so that
+    // the attribute also applies to lambdas? If so, remove HWY_ATTR.
+#if HWY_GENERIC_LAMBDA
+    const auto scal = [](const auto d, const auto v)
+                          HWY_ATTR { return Mul(Set(d, Alpha<T>()), v); };
+#else
+    const SCAL scal;
+#endif
+    Transform(d, a, count, scal);
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected.get(), a, count, target_name,
+                                  __FILE__, __LINE__);
+  }
+};
+
+// One extra input array
+struct TestTransform1 {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    using T = TFromD<D>;
+    // Prevents error if size to allocate is zero.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    AlignedFreeUniquePtr<T[]> pb =
+        AllocateAligned<T>(HWY_MAX(1, misalign_b + count));
+    T* a = pa.get() + misalign_a;
+    T* b = pb.get() + misalign_b;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random<T>(rng);
+      b[i] = Random<T>(rng);
+    }
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(HWY_MAX(1, count));
+    SimpleAXPY(a, b, expected.get(), count);
+
+#if HWY_GENERIC_LAMBDA
+    const auto axpy = [](const auto d, const auto v, const auto v1) HWY_ATTR {
+      return MulAdd(Set(d, Alpha<T>()), v, v1);
+    };
+#else
+    const AXPY axpy;
+#endif
+    Transform1(d, a, count, b, axpy);
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected.get(), a, count, target_name,
+                                  __FILE__, __LINE__);
+  }
+};
+
+// Two extra input arrays
+struct TestTransform2 {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    using T = TFromD<D>;
+    // Prevents error if size to allocate is zero.
+    AlignedFreeUniquePtr<T[]> pa =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    AlignedFreeUniquePtr<T[]> pb =
+        AllocateAligned<T>(HWY_MAX(1, misalign_b + count));
+    AlignedFreeUniquePtr<T[]> pc =
+        AllocateAligned<T>(HWY_MAX(1, misalign_a + count));
+    T* a = pa.get() + misalign_a;
+    T* b = pb.get() + misalign_b;
+    T* c = pc.get() + misalign_a;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random<T>(rng);
+      b[i] = Random<T>(rng);
+      c[i] = Random<T>(rng);
+    }
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(HWY_MAX(1, count));
+    SimpleFMA4(a, b, c, expected.get(), count);
+
+#if HWY_GENERIC_LAMBDA
+    const auto fma4 = [](auto /*d*/, auto v, auto v1, auto v2)
+                          HWY_ATTR { return MulAdd(v, v1, v2); };
+#else
+    const FMA4 fma4;
+#endif
+    Transform2(d, a, count, b, c, fma4);
+
+    const auto info = hwy::detail::MakeTypeInfo<T>();
+    const char* target_name = hwy::TargetName(HWY_TARGET);
+    hwy::detail::AssertArrayEqual(info, expected.get(), a, count, target_name,
+                                  __FILE__, __LINE__);
+  }
+};
+
+template <typename T>
+class IfEq {
+ public:
+  IfEq(T val) : val_(val) {}
+
+  template <class D, class V>
+  Mask<D> operator()(D d, V v) const {
+    return Eq(v, Set(d, val_));
+  }
+
+ private:
+  T val_;
+};
+
+struct TestReplace {
+  template <class D>
+  void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
+                  RandomState& rng) {
+    if (misalign_b != 0) return;
+    if (count == 0) return;
+    using T = TFromD<D>;
+    AlignedFreeUniquePtr<T[]> pa = AllocateAligned<T>(misalign_a + count);
+    T* a = pa.get() + misalign_a;
+    for (size_t i = 0; i < count; ++i) {
+      a[i] = Random<T>(rng);
+    }
+    AlignedFreeUniquePtr<T[]> pb = AllocateAligned<T>(count);
+
+    AlignedFreeUniquePtr<T[]> expected = AllocateAligned<T>(count);
+
+    std::vector<size_t> positions(AdjustedReps(count));
+    for (size_t& pos : positions) {
+      pos = static_cast<size_t>(rng()) % count;
+    }
+
+    for (size_t pos = 0; pos < count; ++pos) {
+      const T old_t = a[pos];
+      const T new_t = Random<T>(rng);
+      for (size_t i = 0; i < count; ++i) {
+        expected[i] = IsEqual(a[i], old_t) ? new_t : a[i];
+      }
+
+      // Copy so ReplaceIf gets the same input (and thus also outputs expected)
+      memcpy(pb.get(), a, count * sizeof(T));
+
+      Replace(d, a, count, new_t, old_t);
+      HWY_ASSERT_ARRAY_EQ(expected.get(), a, count);
+
+      ReplaceIf(d, pb.get(), count, new_t, IfEq<T>(old_t));
+      HWY_ASSERT_ARRAY_EQ(expected.get(), pb.get(), count);
+    }
+  }
+};
+
+void TestAllGenerate() {
+  // The test BitCast-s the indices, which does not work for floats.
+  ForIntegerTypes(ForPartialVectors<ForeachCountAndMisalign<TestGenerate>>());
+}
+
+void TestAllTransform() {
+  ForFloatTypes(ForPartialVectors<ForeachCountAndMisalign<TestTransform>>());
+}
+
+void TestAllTransform1() {
+  ForFloatTypes(ForPartialVectors<ForeachCountAndMisalign<TestTransform1>>());
+}
+
+void TestAllTransform2() {
+  ForFloatTypes(ForPartialVectors<ForeachCountAndMisalign<TestTransform2>>());
+}
+
+void TestAllReplace() {
+  ForFloatTypes(ForPartialVectors<ForeachCountAndMisalign<TestReplace>>());
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace hwy
+HWY_AFTER_NAMESPACE();
+
+#if HWY_ONCE
+
+namespace hwy {
+HWY_BEFORE_TEST(TransformTest);
+HWY_EXPORT_AND_TEST_P(TransformTest, TestAllGenerate);
+HWY_EXPORT_AND_TEST_P(TransformTest, TestAllTransform);
+HWY_EXPORT_AND_TEST_P(TransformTest, TestAllTransform1);
+HWY_EXPORT_AND_TEST_P(TransformTest, TestAllTransform2);
+HWY_EXPORT_AND_TEST_P(TransformTest, TestAllReplace);
+}  // namespace hwy
+
+#endif