1 /* 2 * Copyright (c) 2014 The WebM project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #include <arm_neon.h> 12 13 #include "./vp8_rtcd.h" 14 15 static const int16_t cospi8sqrt2minus1 = 20091; 16 // 35468 exceeds INT16_MAX and gets converted to a negative number. Because of 17 // the way it is used in vqdmulh, where the result is doubled, it can be divided 18 // by 2 beforehand. This saves compensating for the negative value as well as 19 // shifting the result. 20 static const int16_t sinpi8sqrt2 = 35468 >> 1; 21 22 void vp8_short_idct4x4llm_neon(int16_t *input, unsigned char *pred_ptr, 23 int pred_stride, unsigned char *dst_ptr, 24 int dst_stride) { 25 int i; 26 uint32x2_t d6u32 = vdup_n_u32(0); 27 uint8x8_t d1u8; 28 int16x4_t d2, d3, d4, d5, d10, d11, d12, d13; 29 uint16x8_t q1u16; 30 int16x8_t q1s16, q2s16, q3s16, q4s16; 31 int32x2x2_t v2tmp0, v2tmp1; 32 int16x4x2_t v2tmp2, v2tmp3; 33 34 d2 = vld1_s16(input); 35 d3 = vld1_s16(input + 4); 36 d4 = vld1_s16(input + 8); 37 d5 = vld1_s16(input + 12); 38 39 // 1st for loop 40 q1s16 = vcombine_s16(d2, d4); // Swap d3 d4 here 41 q2s16 = vcombine_s16(d3, d5); 42 43 q3s16 = vqdmulhq_n_s16(q2s16, sinpi8sqrt2); 44 q4s16 = vqdmulhq_n_s16(q2s16, cospi8sqrt2minus1); 45 46 d12 = vqadd_s16(vget_low_s16(q1s16), vget_high_s16(q1s16)); // a1 47 d13 = vqsub_s16(vget_low_s16(q1s16), vget_high_s16(q1s16)); // b1 48 49 q4s16 = vshrq_n_s16(q4s16, 1); 50 51 q4s16 = vqaddq_s16(q4s16, q2s16); 52 53 d10 = vqsub_s16(vget_low_s16(q3s16), vget_high_s16(q4s16)); // c1 54 d11 = vqadd_s16(vget_high_s16(q3s16), vget_low_s16(q4s16)); // d1 55 56 d2 = vqadd_s16(d12, d11); 57 d3 = vqadd_s16(d13, d10); 58 d4 = vqsub_s16(d13, d10); 59 d5 = vqsub_s16(d12, d11); 60 61 v2tmp0 = vtrn_s32(vreinterpret_s32_s16(d2), vreinterpret_s32_s16(d4)); 62 v2tmp1 = vtrn_s32(vreinterpret_s32_s16(d3), vreinterpret_s32_s16(d5)); 63 v2tmp2 = vtrn_s16(vreinterpret_s16_s32(v2tmp0.val[0]), 64 vreinterpret_s16_s32(v2tmp1.val[0])); 65 v2tmp3 = vtrn_s16(vreinterpret_s16_s32(v2tmp0.val[1]), 66 vreinterpret_s16_s32(v2tmp1.val[1])); 67 68 // 2nd for loop 69 q1s16 = vcombine_s16(v2tmp2.val[0], v2tmp3.val[0]); 70 q2s16 = vcombine_s16(v2tmp2.val[1], v2tmp3.val[1]); 71 72 q3s16 = vqdmulhq_n_s16(q2s16, sinpi8sqrt2); 73 q4s16 = vqdmulhq_n_s16(q2s16, cospi8sqrt2minus1); 74 75 d12 = vqadd_s16(vget_low_s16(q1s16), vget_high_s16(q1s16)); // a1 76 d13 = vqsub_s16(vget_low_s16(q1s16), vget_high_s16(q1s16)); // b1 77 78 q4s16 = vshrq_n_s16(q4s16, 1); 79 80 q4s16 = vqaddq_s16(q4s16, q2s16); 81 82 d10 = vqsub_s16(vget_low_s16(q3s16), vget_high_s16(q4s16)); // c1 83 d11 = vqadd_s16(vget_high_s16(q3s16), vget_low_s16(q4s16)); // d1 84 85 d2 = vqadd_s16(d12, d11); 86 d3 = vqadd_s16(d13, d10); 87 d4 = vqsub_s16(d13, d10); 88 d5 = vqsub_s16(d12, d11); 89 90 d2 = vrshr_n_s16(d2, 3); 91 d3 = vrshr_n_s16(d3, 3); 92 d4 = vrshr_n_s16(d4, 3); 93 d5 = vrshr_n_s16(d5, 3); 94 95 v2tmp0 = vtrn_s32(vreinterpret_s32_s16(d2), vreinterpret_s32_s16(d4)); 96 v2tmp1 = vtrn_s32(vreinterpret_s32_s16(d3), vreinterpret_s32_s16(d5)); 97 v2tmp2 = vtrn_s16(vreinterpret_s16_s32(v2tmp0.val[0]), 98 vreinterpret_s16_s32(v2tmp1.val[0])); 99 v2tmp3 = vtrn_s16(vreinterpret_s16_s32(v2tmp0.val[1]), 100 vreinterpret_s16_s32(v2tmp1.val[1])); 101 102 q1s16 = vcombine_s16(v2tmp2.val[0], v2tmp2.val[1]); 103 q2s16 = vcombine_s16(v2tmp3.val[0], v2tmp3.val[1]); 104 105 // dc_only_idct_add 106 for (i = 0; i < 2; i++, q1s16 = q2s16) { 107 d6u32 = vld1_lane_u32((const uint32_t *)pred_ptr, d6u32, 0); 108 pred_ptr += pred_stride; 109 d6u32 = vld1_lane_u32((const uint32_t *)pred_ptr, d6u32, 1); 110 pred_ptr += pred_stride; 111 112 q1u16 = vaddw_u8(vreinterpretq_u16_s16(q1s16), vreinterpret_u8_u32(d6u32)); 113 d1u8 = vqmovun_s16(vreinterpretq_s16_u16(q1u16)); 114 115 vst1_lane_u32((uint32_t *)dst_ptr, vreinterpret_u32_u8(d1u8), 0); 116 dst_ptr += dst_stride; 117 vst1_lane_u32((uint32_t *)dst_ptr, vreinterpret_u32_u8(d1u8), 1); 118 dst_ptr += dst_stride; 119 } 120 return; 121 } 122