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diff --git a/media/libjxl/src/lib/jxl/quantizer-inl.h b/media/libjxl/src/lib/jxl/quantizer-inl.h
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+++ b/media/libjxl/src/lib/jxl/quantizer-inl.h
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+// Copyright (c) the JPEG XL Project Authors. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#if defined(LIB_JXL_QUANTIZER_INL_H_) == defined(HWY_TARGET_TOGGLE)
+#ifdef LIB_JXL_QUANTIZER_INL_H_
+#undef LIB_JXL_QUANTIZER_INL_H_
+#else
+#define LIB_JXL_QUANTIZER_INL_H_
+#endif
+
+#include <stddef.h>
+
+#include <hwy/highway.h>
+HWY_BEFORE_NAMESPACE();
+namespace jxl {
+namespace HWY_NAMESPACE {
+namespace {
+
+// These templates are not found via ADL.
+using hwy::HWY_NAMESPACE::Rebind;
+using hwy::HWY_NAMESPACE::Vec;
+
+template <class DI>
+HWY_INLINE HWY_MAYBE_UNUSED Vec<Rebind<float, DI>> AdjustQuantBias(
+    DI di, const size_t c, const Vec<DI> quant_i,
+    const float* HWY_RESTRICT biases) {
+  const Rebind<float, DI> df;
+
+  const auto quant = ConvertTo(df, quant_i);
+
+  // Compare |quant|, keep sign bit for negating result.
+  const auto kSign = BitCast(df, Set(di, INT32_MIN));
+  const auto sign = And(quant, kSign);  // TODO(janwas): = abs ^ orig
+  const auto abs_quant = AndNot(kSign, quant);
+
+  // If |x| is 1, kZeroBias creates a different bias for each channel.
+  // We're implementing the following:
+  // if (quant == 0) return 0;
+  // if (quant == 1) return biases[c];
+  // if (quant == -1) return -biases[c];
+  // return quant - biases[3] / quant;
+
+  // Integer comparison is not helpful because Clang incurs bypass penalties
+  // from unnecessarily mixing integer and float.
+  const auto is_01 = abs_quant < Set(df, 1.125f);
+  const auto not_0 = abs_quant > Zero(df);
+
+  // Bitwise logic is faster than quant * biases[c].
+  const auto one_bias = IfThenElseZero(not_0, Xor(Set(df, biases[c]), sign));
+
+  // About 2E-5 worse than ReciprocalNR or division.
+  const auto bias =
+      NegMulAdd(Set(df, biases[3]), ApproximateReciprocal(quant), quant);
+
+  return IfThenElse(is_01, one_bias, bias);
+}
+
+}  // namespace
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace jxl
+HWY_AFTER_NAMESPACE();
+
+#endif  // LIB_JXL_QUANTIZER_INL_H_