ref: 1c85230344aa4854dfb8aa3c7bceaea183d66dce
dir: /vpx_dsp/arm/hadamard_neon.c/
/*
* Copyright (c) 2016 The WebM 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 in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <arm_neon.h>
#include "./vpx_dsp_rtcd.h"
static void hadamard8x8_one_pass(int16x8_t *a0, int16x8_t *a1, int16x8_t *a2,
int16x8_t *a3, int16x8_t *a4, int16x8_t *a5,
int16x8_t *a6, int16x8_t *a7) {
const int16x8_t b0 = vaddq_s16(*a0, *a1);
const int16x8_t b1 = vsubq_s16(*a0, *a1);
const int16x8_t b2 = vaddq_s16(*a2, *a3);
const int16x8_t b3 = vsubq_s16(*a2, *a3);
const int16x8_t b4 = vaddq_s16(*a4, *a5);
const int16x8_t b5 = vsubq_s16(*a4, *a5);
const int16x8_t b6 = vaddq_s16(*a6, *a7);
const int16x8_t b7 = vsubq_s16(*a6, *a7);
const int16x8_t c0 = vaddq_s16(b0, b2);
const int16x8_t c1 = vaddq_s16(b1, b3);
const int16x8_t c2 = vsubq_s16(b0, b2);
const int16x8_t c3 = vsubq_s16(b1, b3);
const int16x8_t c4 = vaddq_s16(b4, b6);
const int16x8_t c5 = vaddq_s16(b5, b7);
const int16x8_t c6 = vsubq_s16(b4, b6);
const int16x8_t c7 = vsubq_s16(b5, b7);
*a0 = vaddq_s16(c0, c4);
*a1 = vsubq_s16(c2, c6);
*a2 = vsubq_s16(c0, c4);
*a3 = vaddq_s16(c2, c6);
*a4 = vaddq_s16(c3, c7);
*a5 = vsubq_s16(c3, c7);
*a6 = vsubq_s16(c1, c5);
*a7 = vaddq_s16(c1, c5);
}
// TODO(johannkoenig): Make a transpose library and dedup with idct. Consider
// reversing transpose order which may make it easier for the compiler to
// reconcile the vtrn.64 moves.
static void transpose8x8(int16x8_t *a0, int16x8_t *a1, int16x8_t *a2,
int16x8_t *a3, int16x8_t *a4, int16x8_t *a5,
int16x8_t *a6, int16x8_t *a7) {
// Swap 64 bit elements. Goes from:
// a0: 00 01 02 03 04 05 06 07
// a1: 08 09 10 11 12 13 14 15
// a2: 16 17 18 19 20 21 22 23
// a3: 24 25 26 27 28 29 30 31
// a4: 32 33 34 35 36 37 38 39
// a5: 40 41 42 43 44 45 46 47
// a6: 48 49 50 51 52 53 54 55
// a7: 56 57 58 59 60 61 62 63
// to:
// a04_lo: 00 01 02 03 32 33 34 35
// a15_lo: 08 09 10 11 40 41 42 43
// a26_lo: 16 17 18 19 48 49 50 51
// a37_lo: 24 25 26 27 56 57 58 59
// a04_hi: 04 05 06 07 36 37 38 39
// a15_hi: 12 13 14 15 44 45 46 47
// a26_hi: 20 21 22 23 52 53 54 55
// a37_hi: 28 29 30 31 60 61 62 63
const int16x8_t a04_lo = vcombine_s16(vget_low_s16(*a0), vget_low_s16(*a4));
const int16x8_t a15_lo = vcombine_s16(vget_low_s16(*a1), vget_low_s16(*a5));
const int16x8_t a26_lo = vcombine_s16(vget_low_s16(*a2), vget_low_s16(*a6));
const int16x8_t a37_lo = vcombine_s16(vget_low_s16(*a3), vget_low_s16(*a7));
const int16x8_t a04_hi = vcombine_s16(vget_high_s16(*a0), vget_high_s16(*a4));
const int16x8_t a15_hi = vcombine_s16(vget_high_s16(*a1), vget_high_s16(*a5));
const int16x8_t a26_hi = vcombine_s16(vget_high_s16(*a2), vget_high_s16(*a6));
const int16x8_t a37_hi = vcombine_s16(vget_high_s16(*a3), vget_high_s16(*a7));
// Swap 32 bit elements resulting in:
// a0246_lo:
// 00 01 16 17 32 33 48 49
// 02 03 18 19 34 35 50 51
// a1357_lo:
// 08 09 24 25 40 41 56 57
// 10 11 26 27 42 43 58 59
// a0246_hi:
// 04 05 20 21 36 37 52 53
// 06 07 22 23 38 39 54 55
// a1657_hi:
// 12 13 28 29 44 45 60 61
// 14 15 30 31 46 47 62 63
const int32x4x2_t a0246_lo =
vtrnq_s32(vreinterpretq_s32_s16(a04_lo), vreinterpretq_s32_s16(a26_lo));
const int32x4x2_t a1357_lo =
vtrnq_s32(vreinterpretq_s32_s16(a15_lo), vreinterpretq_s32_s16(a37_lo));
const int32x4x2_t a0246_hi =
vtrnq_s32(vreinterpretq_s32_s16(a04_hi), vreinterpretq_s32_s16(a26_hi));
const int32x4x2_t a1357_hi =
vtrnq_s32(vreinterpretq_s32_s16(a15_hi), vreinterpretq_s32_s16(a37_hi));
// Swap 16 bit elements resulting in:
// b0:
// 00 08 16 24 32 40 48 56
// 01 09 17 25 33 41 49 57
// b1:
// 02 10 18 26 34 42 50 58
// 03 11 19 27 35 43 51 59
// b2:
// 04 12 20 28 36 44 52 60
// 05 13 21 29 37 45 53 61
// b3:
// 06 14 22 30 38 46 54 62
// 07 15 23 31 39 47 55 63
const int16x8x2_t b0 = vtrnq_s16(vreinterpretq_s16_s32(a0246_lo.val[0]),
vreinterpretq_s16_s32(a1357_lo.val[0]));
const int16x8x2_t b1 = vtrnq_s16(vreinterpretq_s16_s32(a0246_lo.val[1]),
vreinterpretq_s16_s32(a1357_lo.val[1]));
const int16x8x2_t b2 = vtrnq_s16(vreinterpretq_s16_s32(a0246_hi.val[0]),
vreinterpretq_s16_s32(a1357_hi.val[0]));
const int16x8x2_t b3 = vtrnq_s16(vreinterpretq_s16_s32(a0246_hi.val[1]),
vreinterpretq_s16_s32(a1357_hi.val[1]));
*a0 = b0.val[0];
*a1 = b0.val[1];
*a2 = b1.val[0];
*a3 = b1.val[1];
*a4 = b2.val[0];
*a5 = b2.val[1];
*a6 = b3.val[0];
*a7 = b3.val[1];
}
void vpx_hadamard_8x8_neon(const int16_t *src_diff, int src_stride,
int16_t *coeff) {
int16x8_t a0 = vld1q_s16(src_diff);
int16x8_t a1 = vld1q_s16(src_diff + src_stride);
int16x8_t a2 = vld1q_s16(src_diff + 2 * src_stride);
int16x8_t a3 = vld1q_s16(src_diff + 3 * src_stride);
int16x8_t a4 = vld1q_s16(src_diff + 4 * src_stride);
int16x8_t a5 = vld1q_s16(src_diff + 5 * src_stride);
int16x8_t a6 = vld1q_s16(src_diff + 6 * src_stride);
int16x8_t a7 = vld1q_s16(src_diff + 7 * src_stride);
hadamard8x8_one_pass(&a0, &a1, &a2, &a3, &a4, &a5, &a6, &a7);
transpose8x8(&a0, &a1, &a2, &a3, &a4, &a5, &a6, &a7);
hadamard8x8_one_pass(&a0, &a1, &a2, &a3, &a4, &a5, &a6, &a7);
// Skip the second transpose because it is not required.
vst1q_s16(coeff + 0, a0);
vst1q_s16(coeff + 8, a1);
vst1q_s16(coeff + 16, a2);
vst1q_s16(coeff + 24, a3);
vst1q_s16(coeff + 32, a4);
vst1q_s16(coeff + 40, a5);
vst1q_s16(coeff + 48, a6);
vst1q_s16(coeff + 56, a7);
}
void vpx_hadamard_16x16_neon(const int16_t *src_diff, int src_stride,
int16_t *coeff) {
int i;
/* Rearrange 16x16 to 8x32 and remove stride.
* Top left first. */
vpx_hadamard_8x8_neon(src_diff + 0 + 0 * src_stride, src_stride, coeff + 0);
/* Top right. */
vpx_hadamard_8x8_neon(src_diff + 8 + 0 * src_stride, src_stride, coeff + 64);
/* Bottom left. */
vpx_hadamard_8x8_neon(src_diff + 0 + 8 * src_stride, src_stride, coeff + 128);
/* Bottom right. */
vpx_hadamard_8x8_neon(src_diff + 8 + 8 * src_stride, src_stride, coeff + 192);
for (i = 0; i < 64; i += 8) {
const int16x8_t a0 = vld1q_s16(coeff + 0);
const int16x8_t a1 = vld1q_s16(coeff + 64);
const int16x8_t a2 = vld1q_s16(coeff + 128);
const int16x8_t a3 = vld1q_s16(coeff + 192);
const int16x8_t b0 = vhaddq_s16(a0, a1);
const int16x8_t b1 = vhsubq_s16(a0, a1);
const int16x8_t b2 = vhaddq_s16(a2, a3);
const int16x8_t b3 = vhsubq_s16(a2, a3);
const int16x8_t c0 = vaddq_s16(b0, b2);
const int16x8_t c1 = vaddq_s16(b1, b3);
const int16x8_t c2 = vsubq_s16(b0, b2);
const int16x8_t c3 = vsubq_s16(b1, b3);
vst1q_s16(coeff + 0, c0);
vst1q_s16(coeff + 64, c1);
vst1q_s16(coeff + 128, c2);
vst1q_s16(coeff + 192, c3);
coeff += 8;
}
}