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diff --git a/third_party/jpeg-xl/lib/jpegli/dct-inl.h b/third_party/jpeg-xl/lib/jpegli/dct-inl.h
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+++ b/third_party/jpeg-xl/lib/jpegli/dct-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_JPEGLI_DCT_INL_H_) == defined(HWY_TARGET_TOGGLE)
+#ifdef LIB_JPEGLI_DCT_INL_H_
+#undef LIB_JPEGLI_DCT_INL_H_
+#else
+#define LIB_JPEGLI_DCT_INL_H_
+#endif
+
+#include "lib/jpegli/transpose-inl.h"
+#include "lib/jxl/base/compiler_specific.h"
+
+HWY_BEFORE_NAMESPACE();
+namespace jpegli {
+namespace HWY_NAMESPACE {
+namespace {
+
+// These templates are not found via ADL.
+using hwy::HWY_NAMESPACE::Abs;
+using hwy::HWY_NAMESPACE::Add;
+using hwy::HWY_NAMESPACE::DemoteTo;
+using hwy::HWY_NAMESPACE::Ge;
+using hwy::HWY_NAMESPACE::IfThenElseZero;
+using hwy::HWY_NAMESPACE::Mul;
+using hwy::HWY_NAMESPACE::MulAdd;
+using hwy::HWY_NAMESPACE::Rebind;
+using hwy::HWY_NAMESPACE::Round;
+using hwy::HWY_NAMESPACE::Sub;
+using hwy::HWY_NAMESPACE::Vec;
+
+using D = HWY_FULL(float);
+using DI = HWY_FULL(int32_t);
+
+template <size_t N>
+void AddReverse(const float* JXL_RESTRICT ain1, const float* JXL_RESTRICT ain2,
+ float* JXL_RESTRICT aout) {
+ HWY_CAPPED(float, 8) d8;
+ for (size_t i = 0; i < N; i++) {
+ auto in1 = Load(d8, ain1 + i * 8);
+ auto in2 = Load(d8, ain2 + (N - i - 1) * 8);
+ Store(Add(in1, in2), d8, aout + i * 8);
+ }
+}
+
+template <size_t N>
+void SubReverse(const float* JXL_RESTRICT ain1, const float* JXL_RESTRICT ain2,
+ float* JXL_RESTRICT aout) {
+ HWY_CAPPED(float, 8) d8;
+ for (size_t i = 0; i < N; i++) {
+ auto in1 = Load(d8, ain1 + i * 8);
+ auto in2 = Load(d8, ain2 + (N - i - 1) * 8);
+ Store(Sub(in1, in2), d8, aout + i * 8);
+ }
+}
+
+template <size_t N>
+void B(float* JXL_RESTRICT coeff) {
+ HWY_CAPPED(float, 8) d8;
+ constexpr float kSqrt2 = 1.41421356237f;
+ auto sqrt2 = Set(d8, kSqrt2);
+ auto in1 = Load(d8, coeff);
+ auto in2 = Load(d8, coeff + 8);
+ Store(MulAdd(in1, sqrt2, in2), d8, coeff);
+ for (size_t i = 1; i + 1 < N; i++) {
+ auto in1 = Load(d8, coeff + i * 8);
+ auto in2 = Load(d8, coeff + (i + 1) * 8);
+ Store(Add(in1, in2), d8, coeff + i * 8);
+ }
+}
+
+// Ideally optimized away by compiler (except the multiply).
+template <size_t N>
+void InverseEvenOdd(const float* JXL_RESTRICT ain, float* JXL_RESTRICT aout) {
+ HWY_CAPPED(float, 8) d8;
+ for (size_t i = 0; i < N / 2; i++) {
+ auto in1 = Load(d8, ain + i * 8);
+ Store(in1, d8, aout + 2 * i * 8);
+ }
+ for (size_t i = N / 2; i < N; i++) {
+ auto in1 = Load(d8, ain + i * 8);
+ Store(in1, d8, aout + (2 * (i - N / 2) + 1) * 8);
+ }
+}
+
+// Constants for DCT implementation. Generated by the following snippet:
+// for i in range(N // 2):
+// print(1.0 / (2 * math.cos((i + 0.5) * math.pi / N)), end=", ")
+template <size_t N>
+struct WcMultipliers;
+
+template <>
+struct WcMultipliers<4> {
+ static constexpr float kMultipliers[] = {
+ 0.541196100146197,
+ 1.3065629648763764,
+ };
+};
+
+template <>
+struct WcMultipliers<8> {
+ static constexpr float kMultipliers[] = {
+ 0.5097955791041592,
+ 0.6013448869350453,
+ 0.8999762231364156,
+ 2.5629154477415055,
+ };
+};
+
+constexpr float WcMultipliers<4>::kMultipliers[];
+constexpr float WcMultipliers<8>::kMultipliers[];
+
+// Invoked on full vector.
+template <size_t N>
+void Multiply(float* JXL_RESTRICT coeff) {
+ HWY_CAPPED(float, 8) d8;
+ for (size_t i = 0; i < N / 2; i++) {
+ auto in1 = Load(d8, coeff + (N / 2 + i) * 8);
+ auto mul = Set(d8, WcMultipliers<N>::kMultipliers[i]);
+ Store(Mul(in1, mul), d8, coeff + (N / 2 + i) * 8);
+ }
+}
+
+void LoadFromBlock(const float* JXL_RESTRICT pixels, size_t pixels_stride,
+ size_t off, float* JXL_RESTRICT coeff) {
+ HWY_CAPPED(float, 8) d8;
+ for (size_t i = 0; i < 8; i++) {
+ Store(LoadU(d8, pixels + i * pixels_stride + off), d8, coeff + i * 8);
+ }
+}
+
+void StoreToBlockAndScale(const float* JXL_RESTRICT coeff, float* output,
+ size_t off) {
+ HWY_CAPPED(float, 8) d8;
+ auto mul = Set(d8, 1.0f / 8);
+ for (size_t i = 0; i < 8; i++) {
+ StoreU(Mul(mul, Load(d8, coeff + i * 8)), d8, output + i * 8 + off);
+ }
+}
+
+template <size_t N>
+struct DCT1DImpl;
+
+template <>
+struct DCT1DImpl<1> {
+ JXL_INLINE void operator()(float* JXL_RESTRICT mem) {}
+};
+
+template <>
+struct DCT1DImpl<2> {
+ JXL_INLINE void operator()(float* JXL_RESTRICT mem) {
+ HWY_CAPPED(float, 8) d8;
+ auto in1 = Load(d8, mem);
+ auto in2 = Load(d8, mem + 8);
+ Store(Add(in1, in2), d8, mem);
+ Store(Sub(in1, in2), d8, mem + 8);
+ }
+};
+
+template <size_t N>
+struct DCT1DImpl {
+ void operator()(float* JXL_RESTRICT mem) {
+ HWY_ALIGN float tmp[N * 8];
+ AddReverse<N / 2>(mem, mem + N * 4, tmp);
+ DCT1DImpl<N / 2>()(tmp);
+ SubReverse<N / 2>(mem, mem + N * 4, tmp + N * 4);
+ Multiply<N>(tmp);
+ DCT1DImpl<N / 2>()(tmp + N * 4);
+ B<N / 2>(tmp + N * 4);
+ InverseEvenOdd<N>(tmp, mem);
+ }
+};
+
+void DCT1D(const float* JXL_RESTRICT pixels, size_t pixels_stride,
+ float* JXL_RESTRICT output) {
+ HWY_CAPPED(float, 8) d8;
+ HWY_ALIGN float tmp[64];
+ for (size_t i = 0; i < 8; i += Lanes(d8)) {
+ // TODO(veluca): consider removing the temporary memory here (as is done in
+ // IDCT), if it turns out that some compilers don't optimize away the loads
+ // and this is performance-critical.
+ LoadFromBlock(pixels, pixels_stride, i, tmp);
+ DCT1DImpl<8>()(tmp);
+ StoreToBlockAndScale(tmp, output, i);
+ }
+}
+
+void TransformFromPixels(const float* JXL_RESTRICT pixels, size_t pixels_stride,
+ float* JXL_RESTRICT coefficients,
+ float* JXL_RESTRICT scratch_space) {
+ DCT1D(pixels, pixels_stride, scratch_space);
+ Transpose8x8Block(scratch_space, coefficients);
+ DCT1D(coefficients, 8, scratch_space);
+ Transpose8x8Block(scratch_space, coefficients);
+}
+
+void StoreQuantizedValue(const Vec<DI>& ival, int16_t* out) {
+ Rebind<int16_t, DI> di16;
+ Store(DemoteTo(di16, ival), di16, out);
+}
+
+void StoreQuantizedValue(const Vec<DI>& ival, int32_t* out) {
+ DI di;
+ Store(ival, di, out);
+}
+
+template <typename T>
+void QuantizeBlock(const float* dct, const float* qmc, float aq_strength,
+ const float* zero_bias_offset, const float* zero_bias_mul,
+ T* block) {
+ D d;
+ DI di;
+ const auto aq_mul = Set(d, aq_strength);
+ for (size_t k = 0; k < DCTSIZE2; k += Lanes(d)) {
+ const auto val = Load(d, dct + k);
+ const auto q = Load(d, qmc + k);
+ const auto qval = Mul(val, q);
+ const auto zb_offset = Load(d, zero_bias_offset + k);
+ const auto zb_mul = Load(d, zero_bias_mul + k);
+ const auto threshold = Add(zb_offset, Mul(zb_mul, aq_mul));
+ const auto nzero_mask = Ge(Abs(qval), threshold);
+ const auto ival = ConvertTo(di, IfThenElseZero(nzero_mask, Round(qval)));
+ StoreQuantizedValue(ival, block + k);
+ }
+}
+
+template <typename T>
+void QuantizeBlockNoAQ(const float* dct, const float* qmc, T* block) {
+ D d;
+ DI di;
+ for (size_t k = 0; k < DCTSIZE2; k += Lanes(d)) {
+ const auto val = Load(d, dct + k);
+ const auto q = Load(d, qmc + k);
+ const auto ival = ConvertTo(di, Round(Mul(val, q)));
+ StoreQuantizedValue(ival, block + k);
+ }
+}
+
+template <typename T>
+void ComputeCoefficientBlock(const float* JXL_RESTRICT pixels, size_t stride,
+ const float* JXL_RESTRICT qmc, float aq_strength,
+ const float* zero_bias_offset,
+ const float* zero_bias_mul,
+ float* JXL_RESTRICT tmp, T* block) {
+ float* JXL_RESTRICT dct = tmp;
+ float* JXL_RESTRICT scratch_space = tmp + DCTSIZE2;
+ TransformFromPixels(pixels, stride, dct, scratch_space);
+ if (aq_strength > 0.0f) {
+ QuantizeBlock(dct, qmc, aq_strength, zero_bias_offset, zero_bias_mul,
+ block);
+ } else {
+ QuantizeBlockNoAQ(dct, qmc, block);
+ }
+ // Center DC values around zero.
+ static constexpr float kDCBias = 128.0f;
+ block[0] = std::round((dct[0] - kDCBias) * qmc[0]);
+}
+
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+} // namespace
+} // namespace HWY_NAMESPACE
+} // namespace jpegli
+HWY_AFTER_NAMESPACE();
+#endif // LIB_JPEGLI_DCT_INL_H_
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-25 08:37:18 +0000