|  | /* | 
|  | *  Copyright 2014 The LibYuv 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 "libyuv/scale.h" | 
|  | #include "libyuv/row.h" | 
|  | #include "libyuv/scale_row.h" | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | namespace libyuv { | 
|  | extern "C" { | 
|  | #endif | 
|  |  | 
|  | // This module is for GCC Neon armv8 64 bit. | 
|  | #if !defined(LIBYUV_DISABLE_NEON) && defined(__aarch64__) | 
|  |  | 
|  | // Read 32x1 throw away even pixels, and write 16x1. | 
|  | void ScaleRowDown2_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | // load even pixels into v0, odd into v1 | 
|  | MEMACCESS(0) | 
|  | "ld2        {v0.16b,v1.16b}, [%0], #32     \n" | 
|  | "subs       %w2, %w2, #16                  \n"  // 16 processed per loop | 
|  | MEMACCESS(1) | 
|  | "st1        {v1.16b}, [%1], #16            \n"  // store odd pixels | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst),              // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : | 
|  | : "v0", "v1"              // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Read 32x1 average down and write 16x1. | 
|  | void ScaleRowDown2Linear_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.16b,v1.16b}, [%0], #32     \n"  // load pixels and post inc | 
|  | "subs       %w2, %w2, #16                  \n"  // 16 processed per loop | 
|  | "uaddlp     v0.8h, v0.16b                  \n"  // add adjacent | 
|  | "uaddlp     v1.8h, v1.16b                  \n" | 
|  | "rshrn      v0.8b, v0.8h, #1               \n"  // downshift, round and pack | 
|  | "rshrn2     v0.16b, v1.8h, #1              \n" | 
|  | MEMACCESS(1) | 
|  | "st1        {v0.16b}, [%1], #16            \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst),              // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : | 
|  | : "v0", "v1"     // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Read 32x2 average down and write 16x1. | 
|  | void ScaleRowDown2Box_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst, int dst_width) { | 
|  | asm volatile ( | 
|  | // change the stride to row 2 pointer | 
|  | "add        %1, %1, %0                     \n" | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.16b,v1.16b}, [%0], #32    \n"  // load row 1 and post inc | 
|  | MEMACCESS(1) | 
|  | "ld1        {v2.16b, v3.16b}, [%1], #32    \n"  // load row 2 and post inc | 
|  | "subs       %w3, %w3, #16                  \n"  // 16 processed per loop | 
|  | "uaddlp     v0.8h, v0.16b                  \n"  // row 1 add adjacent | 
|  | "uaddlp     v1.8h, v1.16b                  \n" | 
|  | "uadalp     v0.8h, v2.16b                  \n"  // row 2 add adjacent + row1 | 
|  | "uadalp     v1.8h, v3.16b                  \n" | 
|  | "rshrn      v0.8b, v0.8h, #2               \n"  // downshift, round and pack | 
|  | "rshrn2     v0.16b, v1.8h, #2              \n" | 
|  | MEMACCESS(2) | 
|  | "st1        {v0.16b}, [%2], #16            \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(src_stride),       // %1 | 
|  | "+r"(dst),              // %2 | 
|  | "+r"(dst_width)         // %3 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3"     // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleRowDown4_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld4     {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32          \n"  // src line 0 | 
|  | "subs       %w2, %w2, #8                   \n"  // 8 processed per loop | 
|  | MEMACCESS(1) | 
|  | "st1     {v2.8b}, [%1], #8                 \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleRowDown4Box_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | const uint8* src_ptr1 = src_ptr + src_stride; | 
|  | const uint8* src_ptr2 = src_ptr + src_stride * 2; | 
|  | const uint8* src_ptr3 = src_ptr + src_stride * 3; | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld1     {v0.16b}, [%0], #16               \n"   // load up 16x4 | 
|  | MEMACCESS(3) | 
|  | "ld1     {v1.16b}, [%2], #16               \n" | 
|  | MEMACCESS(4) | 
|  | "ld1     {v2.16b}, [%3], #16               \n" | 
|  | MEMACCESS(5) | 
|  | "ld1     {v3.16b}, [%4], #16               \n" | 
|  | "subs    %w5, %w5, #4                      \n" | 
|  | "uaddlp  v0.8h, v0.16b                     \n" | 
|  | "uadalp  v0.8h, v1.16b                     \n" | 
|  | "uadalp  v0.8h, v2.16b                     \n" | 
|  | "uadalp  v0.8h, v3.16b                     \n" | 
|  | "addp    v0.8h, v0.8h, v0.8h               \n" | 
|  | "rshrn   v0.8b, v0.8h, #4                  \n"   // divide by 16 w/rounding | 
|  | MEMACCESS(1) | 
|  | "st1    {v0.s}[0], [%1], #4                \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),   // %0 | 
|  | "+r"(dst_ptr),   // %1 | 
|  | "+r"(src_ptr1),  // %2 | 
|  | "+r"(src_ptr2),  // %3 | 
|  | "+r"(src_ptr3),  // %4 | 
|  | "+r"(dst_width)  // %5 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Down scale from 4 to 3 pixels. Use the neon multilane read/write | 
|  | // to load up the every 4th pixel into a 4 different registers. | 
|  | // Point samples 32 pixels to 24 pixels. | 
|  | void ScaleRowDown34_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                                  \n" | 
|  | MEMACCESS(0) | 
|  | "ld4       {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32                \n"  // src line 0 | 
|  | "subs      %w2, %w2, #24                           \n" | 
|  | "orr       v2.16b, v3.16b, v3.16b                  \n"  // order v0, v1, v2 | 
|  | MEMACCESS(1) | 
|  | "st3       {v0.8b,v1.8b,v2.8b}, [%1], #24                \n" | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleRowDown34_0_Box_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | asm volatile ( | 
|  | "movi      v20.8b, #3                              \n" | 
|  | "add       %3, %3, %0                              \n" | 
|  | "1:                                                  \n" | 
|  | MEMACCESS(0) | 
|  | "ld4       {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32                \n"  // src line 0 | 
|  | MEMACCESS(3) | 
|  | "ld4       {v4.8b,v5.8b,v6.8b,v7.8b}, [%3], #32                \n"  // src line 1 | 
|  | "subs         %w2, %w2, #24                        \n" | 
|  |  | 
|  | // filter src line 0 with src line 1 | 
|  | // expand chars to shorts to allow for room | 
|  | // when adding lines together | 
|  | "ushll     v16.8h, v4.8b, #0                       \n" | 
|  | "ushll     v17.8h, v5.8b, #0                       \n" | 
|  | "ushll     v18.8h, v6.8b, #0                       \n" | 
|  | "ushll     v19.8h, v7.8b, #0                       \n" | 
|  |  | 
|  | // 3 * line_0 + line_1 | 
|  | "umlal     v16.8h, v0.8b, v20.8b                   \n" | 
|  | "umlal     v17.8h, v1.8b, v20.8b                   \n" | 
|  | "umlal     v18.8h, v2.8b, v20.8b                   \n" | 
|  | "umlal     v19.8h, v3.8b, v20.8b                   \n" | 
|  |  | 
|  | // (3 * line_0 + line_1) >> 2 | 
|  | "uqrshrn   v0.8b, v16.8h, #2                       \n" | 
|  | "uqrshrn   v1.8b, v17.8h, #2                       \n" | 
|  | "uqrshrn   v2.8b, v18.8h, #2                       \n" | 
|  | "uqrshrn   v3.8b, v19.8h, #2                       \n" | 
|  |  | 
|  | // a0 = (src[0] * 3 + s[1] * 1) >> 2 | 
|  | "ushll     v16.8h, v1.8b, #0                       \n" | 
|  | "umlal     v16.8h, v0.8b, v20.8b                   \n" | 
|  | "uqrshrn   v0.8b, v16.8h, #2                       \n" | 
|  |  | 
|  | // a1 = (src[1] * 1 + s[2] * 1) >> 1 | 
|  | "urhadd    v1.8b, v1.8b, v2.8b                     \n" | 
|  |  | 
|  | // a2 = (src[2] * 1 + s[3] * 3) >> 2 | 
|  | "ushll     v16.8h, v2.8b, #0                       \n" | 
|  | "umlal     v16.8h, v3.8b, v20.8b                   \n" | 
|  | "uqrshrn   v2.8b, v16.8h, #2                       \n" | 
|  |  | 
|  | MEMACCESS(1) | 
|  | "st3       {v0.8b,v1.8b,v2.8b}, [%1], #24                \n" | 
|  |  | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(dst_width),        // %2 | 
|  | "+r"(src_stride)        // %3 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16", "v17", "v18", "v19", | 
|  | "v20", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleRowDown34_1_Box_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | asm volatile ( | 
|  | "movi      v20.8b, #3                              \n" | 
|  | "add       %3, %3, %0                              \n" | 
|  | "1:                                                  \n" | 
|  | MEMACCESS(0) | 
|  | "ld4       {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32                \n"  // src line 0 | 
|  | MEMACCESS(3) | 
|  | "ld4       {v4.8b,v5.8b,v6.8b,v7.8b}, [%3], #32                \n"  // src line 1 | 
|  | "subs         %w2, %w2, #24                        \n" | 
|  | // average src line 0 with src line 1 | 
|  | "urhadd    v0.8b, v0.8b, v4.8b                     \n" | 
|  | "urhadd    v1.8b, v1.8b, v5.8b                     \n" | 
|  | "urhadd    v2.8b, v2.8b, v6.8b                     \n" | 
|  | "urhadd    v3.8b, v3.8b, v7.8b                     \n" | 
|  |  | 
|  | // a0 = (src[0] * 3 + s[1] * 1) >> 2 | 
|  | "ushll     v4.8h, v1.8b, #0                        \n" | 
|  | "umlal     v4.8h, v0.8b, v20.8b                    \n" | 
|  | "uqrshrn   v0.8b, v4.8h, #2                        \n" | 
|  |  | 
|  | // a1 = (src[1] * 1 + s[2] * 1) >> 1 | 
|  | "urhadd    v1.8b, v1.8b, v2.8b                     \n" | 
|  |  | 
|  | // a2 = (src[2] * 1 + s[3] * 3) >> 2 | 
|  | "ushll     v4.8h, v2.8b, #0                        \n" | 
|  | "umlal     v4.8h, v3.8b, v20.8b                    \n" | 
|  | "uqrshrn   v2.8b, v4.8h, #2                        \n" | 
|  |  | 
|  | MEMACCESS(1) | 
|  | "st3       {v0.8b,v1.8b,v2.8b}, [%1], #24                \n" | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(dst_width),        // %2 | 
|  | "+r"(src_stride)        // %3 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v20", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | static uvec8 kShuf38 = | 
|  | { 0, 3, 6, 8, 11, 14, 16, 19, 22, 24, 27, 30, 0, 0, 0, 0 }; | 
|  | static uvec8 kShuf38_2 = | 
|  | { 0, 16, 32, 2, 18, 33, 4, 20, 34, 6, 22, 35, 0, 0, 0, 0 }; | 
|  | static vec16 kMult38_Div6 = | 
|  | { 65536 / 12, 65536 / 12, 65536 / 12, 65536 / 12, | 
|  | 65536 / 12, 65536 / 12, 65536 / 12, 65536 / 12 }; | 
|  | static vec16 kMult38_Div9 = | 
|  | { 65536 / 18, 65536 / 18, 65536 / 18, 65536 / 18, | 
|  | 65536 / 18, 65536 / 18, 65536 / 18, 65536 / 18 }; | 
|  |  | 
|  | // 32 -> 12 | 
|  | void ScaleRowDown38_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | asm volatile ( | 
|  | MEMACCESS(3) | 
|  | "ld1       {v3.16b}, [%3]                          \n" | 
|  | "1:                                                  \n" | 
|  | MEMACCESS(0) | 
|  | "ld1       {v0.16b,v1.16b}, [%0], #32             \n" | 
|  | "subs      %w2, %w2, #12                           \n" | 
|  | "tbl       v2.16b, {v0.16b,v1.16b}, v3.16b        \n" | 
|  | MEMACCESS(1) | 
|  | "st1       {v2.8b}, [%1], #8                       \n" | 
|  | MEMACCESS(1) | 
|  | "st1       {v2.s}[2], [%1], #4                     \n" | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : "r"(&kShuf38)           // %3 | 
|  | : "v0", "v1", "v2", "v3", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // 32x3 -> 12x1 | 
|  | void OMITFP ScaleRowDown38_3_Box_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | const uint8* src_ptr1 = src_ptr + src_stride * 2; | 
|  | ptrdiff_t tmp_src_stride = src_stride; | 
|  |  | 
|  | asm volatile ( | 
|  | MEMACCESS(5) | 
|  | "ld1       {v29.8h}, [%5]                          \n" | 
|  | MEMACCESS(6) | 
|  | "ld1       {v30.16b}, [%6]                         \n" | 
|  | MEMACCESS(7) | 
|  | "ld1       {v31.8h}, [%7]                          \n" | 
|  | "add       %2, %2, %0                              \n" | 
|  | "1:                                                  \n" | 
|  |  | 
|  | // 00 40 01 41 02 42 03 43 | 
|  | // 10 50 11 51 12 52 13 53 | 
|  | // 20 60 21 61 22 62 23 63 | 
|  | // 30 70 31 71 32 72 33 73 | 
|  | MEMACCESS(0) | 
|  | "ld4       {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32                \n" | 
|  | MEMACCESS(3) | 
|  | "ld4       {v4.8b,v5.8b,v6.8b,v7.8b}, [%2], #32                \n" | 
|  | MEMACCESS(4) | 
|  | "ld4       {v16.8b,v17.8b,v18.8b,v19.8b}, [%3], #32              \n" | 
|  | "subs      %w4, %w4, #12                           \n" | 
|  |  | 
|  | // Shuffle the input data around to get align the data | 
|  | //  so adjacent data can be added. 0,1 - 2,3 - 4,5 - 6,7 | 
|  | // 00 10 01 11 02 12 03 13 | 
|  | // 40 50 41 51 42 52 43 53 | 
|  | "trn1      v20.8b, v0.8b, v1.8b                    \n" | 
|  | "trn2      v21.8b, v0.8b, v1.8b                    \n" | 
|  | "trn1      v22.8b, v4.8b, v5.8b                    \n" | 
|  | "trn2      v23.8b, v4.8b, v5.8b                    \n" | 
|  | "trn1      v24.8b, v16.8b, v17.8b                  \n" | 
|  | "trn2      v25.8b, v16.8b, v17.8b                  \n" | 
|  |  | 
|  | // 20 30 21 31 22 32 23 33 | 
|  | // 60 70 61 71 62 72 63 73 | 
|  | "trn1      v0.8b, v2.8b, v3.8b                     \n" | 
|  | "trn2      v1.8b, v2.8b, v3.8b                     \n" | 
|  | "trn1      v4.8b, v6.8b, v7.8b                     \n" | 
|  | "trn2      v5.8b, v6.8b, v7.8b                     \n" | 
|  | "trn1      v16.8b, v18.8b, v19.8b                  \n" | 
|  | "trn2      v17.8b, v18.8b, v19.8b                  \n" | 
|  |  | 
|  | // 00+10 01+11 02+12 03+13 | 
|  | // 40+50 41+51 42+52 43+53 | 
|  | "uaddlp    v20.4h, v20.8b                          \n" | 
|  | "uaddlp    v21.4h, v21.8b                          \n" | 
|  | "uaddlp    v22.4h, v22.8b                          \n" | 
|  | "uaddlp    v23.4h, v23.8b                          \n" | 
|  | "uaddlp    v24.4h, v24.8b                          \n" | 
|  | "uaddlp    v25.4h, v25.8b                          \n" | 
|  |  | 
|  | // 60+70 61+71 62+72 63+73 | 
|  | "uaddlp    v1.4h, v1.8b                            \n" | 
|  | "uaddlp    v5.4h, v5.8b                            \n" | 
|  | "uaddlp    v17.4h, v17.8b                          \n" | 
|  |  | 
|  | // combine source lines | 
|  | "add       v20.4h, v20.4h, v22.4h                  \n" | 
|  | "add       v21.4h, v21.4h, v23.4h                  \n" | 
|  | "add       v20.4h, v20.4h, v24.4h                  \n" | 
|  | "add       v21.4h, v21.4h, v25.4h                  \n" | 
|  | "add       v2.4h, v1.4h, v5.4h                     \n" | 
|  | "add       v2.4h, v2.4h, v17.4h                    \n" | 
|  |  | 
|  | // dst_ptr[3] = (s[6 + st * 0] + s[7 + st * 0] | 
|  | //             + s[6 + st * 1] + s[7 + st * 1] | 
|  | //             + s[6 + st * 2] + s[7 + st * 2]) / 6 | 
|  | "sqrdmulh  v2.8h, v2.8h, v29.8h                    \n" | 
|  | "xtn       v2.8b,  v2.8h                           \n" | 
|  |  | 
|  | // Shuffle 2,3 reg around so that 2 can be added to the | 
|  | //  0,1 reg and 3 can be added to the 4,5 reg. This | 
|  | //  requires expanding from u8 to u16 as the 0,1 and 4,5 | 
|  | //  registers are already expanded. Then do transposes | 
|  | //  to get aligned. | 
|  | // xx 20 xx 30 xx 21 xx 31 xx 22 xx 32 xx 23 xx 33 | 
|  | "ushll     v16.8h, v16.8b, #0                      \n" | 
|  | "uaddl     v0.8h, v0.8b, v4.8b                     \n" | 
|  |  | 
|  | // combine source lines | 
|  | "add       v0.8h, v0.8h, v16.8h                    \n" | 
|  |  | 
|  | // xx 20 xx 21 xx 22 xx 23 | 
|  | // xx 30 xx 31 xx 32 xx 33 | 
|  | "trn1      v1.8h, v0.8h, v0.8h                     \n" | 
|  | "trn2      v4.8h, v0.8h, v0.8h                     \n" | 
|  | "xtn       v0.4h, v1.4s                            \n" | 
|  | "xtn       v4.4h, v4.4s                            \n" | 
|  |  | 
|  | // 0+1+2, 3+4+5 | 
|  | "add       v20.8h, v20.8h, v0.8h                   \n" | 
|  | "add       v21.8h, v21.8h, v4.8h                   \n" | 
|  |  | 
|  | // Need to divide, but can't downshift as the the value | 
|  | //  isn't a power of 2. So multiply by 65536 / n | 
|  | //  and take the upper 16 bits. | 
|  | "sqrdmulh  v0.8h, v20.8h, v31.8h                   \n" | 
|  | "sqrdmulh  v1.8h, v21.8h, v31.8h                   \n" | 
|  |  | 
|  | // Align for table lookup, vtbl requires registers to | 
|  | //  be adjacent | 
|  | "tbl       v3.16b, {v0.16b, v1.16b, v2.16b}, v30.16b \n" | 
|  |  | 
|  | MEMACCESS(1) | 
|  | "st1       {v3.8b}, [%1], #8                       \n" | 
|  | MEMACCESS(1) | 
|  | "st1       {v3.s}[2], [%1], #4                     \n" | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),          // %0 | 
|  | "+r"(dst_ptr),          // %1 | 
|  | "+r"(tmp_src_stride),   // %2 | 
|  | "+r"(src_ptr1),         // %3 | 
|  | "+r"(dst_width)         // %4 | 
|  | : "r"(&kMult38_Div6),     // %5 | 
|  | "r"(&kShuf38_2),        // %6 | 
|  | "r"(&kMult38_Div9)      // %7 | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16", "v17", | 
|  | "v18", "v19", "v20", "v21", "v22", "v23", "v24", "v25", "v29", | 
|  | "v30", "v31", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // 32x2 -> 12x1 | 
|  | void ScaleRowDown38_2_Box_NEON(const uint8* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8* dst_ptr, int dst_width) { | 
|  | // TODO(fbarchard): use src_stride directly for clang 3.5+. | 
|  | ptrdiff_t tmp_src_stride = src_stride; | 
|  | asm volatile ( | 
|  | MEMACCESS(4) | 
|  | "ld1       {v30.8h}, [%4]                          \n" | 
|  | MEMACCESS(5) | 
|  | "ld1       {v31.16b}, [%5]                         \n" | 
|  | "add       %2, %2, %0                              \n" | 
|  | "1:                                                  \n" | 
|  |  | 
|  | // 00 40 01 41 02 42 03 43 | 
|  | // 10 50 11 51 12 52 13 53 | 
|  | // 20 60 21 61 22 62 23 63 | 
|  | // 30 70 31 71 32 72 33 73 | 
|  | MEMACCESS(0) | 
|  | "ld4       {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32                \n" | 
|  | MEMACCESS(3) | 
|  | "ld4       {v4.8b,v5.8b,v6.8b,v7.8b}, [%2], #32                \n" | 
|  | "subs      %w3, %w3, #12                           \n" | 
|  |  | 
|  | // Shuffle the input data around to get align the data | 
|  | //  so adjacent data can be added. 0,1 - 2,3 - 4,5 - 6,7 | 
|  | // 00 10 01 11 02 12 03 13 | 
|  | // 40 50 41 51 42 52 43 53 | 
|  | "trn1      v16.8b, v0.8b, v1.8b                    \n" | 
|  | "trn2      v17.8b, v0.8b, v1.8b                    \n" | 
|  | "trn1      v18.8b, v4.8b, v5.8b                    \n" | 
|  | "trn2      v19.8b, v4.8b, v5.8b                    \n" | 
|  |  | 
|  | // 20 30 21 31 22 32 23 33 | 
|  | // 60 70 61 71 62 72 63 73 | 
|  | "trn1      v0.8b, v2.8b, v3.8b                     \n" | 
|  | "trn2      v1.8b, v2.8b, v3.8b                     \n" | 
|  | "trn1      v4.8b, v6.8b, v7.8b                     \n" | 
|  | "trn2      v5.8b, v6.8b, v7.8b                     \n" | 
|  |  | 
|  | // 00+10 01+11 02+12 03+13 | 
|  | // 40+50 41+51 42+52 43+53 | 
|  | "uaddlp    v16.4h, v16.8b                          \n" | 
|  | "uaddlp    v17.4h, v17.8b                          \n" | 
|  | "uaddlp    v18.4h, v18.8b                          \n" | 
|  | "uaddlp    v19.4h, v19.8b                          \n" | 
|  |  | 
|  | // 60+70 61+71 62+72 63+73 | 
|  | "uaddlp    v1.4h, v1.8b                            \n" | 
|  | "uaddlp    v5.4h, v5.8b                            \n" | 
|  |  | 
|  | // combine source lines | 
|  | "add       v16.4h, v16.4h, v18.4h                  \n" | 
|  | "add       v17.4h, v17.4h, v19.4h                  \n" | 
|  | "add       v2.4h, v1.4h, v5.4h                     \n" | 
|  |  | 
|  | // dst_ptr[3] = (s[6] + s[7] + s[6+st] + s[7+st]) / 4 | 
|  | "uqrshrn   v2.8b, v2.8h, #2                        \n" | 
|  |  | 
|  | // Shuffle 2,3 reg around so that 2 can be added to the | 
|  | //  0,1 reg and 3 can be added to the 4,5 reg. This | 
|  | //  requires expanding from u8 to u16 as the 0,1 and 4,5 | 
|  | //  registers are already expanded. Then do transposes | 
|  | //  to get aligned. | 
|  | // xx 20 xx 30 xx 21 xx 31 xx 22 xx 32 xx 23 xx 33 | 
|  |  | 
|  | // combine source lines | 
|  | "uaddl     v0.8h, v0.8b, v4.8b                     \n" | 
|  |  | 
|  | // xx 20 xx 21 xx 22 xx 23 | 
|  | // xx 30 xx 31 xx 32 xx 33 | 
|  | "trn1      v1.8h, v0.8h, v0.8h                     \n" | 
|  | "trn2      v4.8h, v0.8h, v0.8h                     \n" | 
|  | "xtn       v0.4h, v1.4s                            \n" | 
|  | "xtn       v4.4h, v4.4s                            \n" | 
|  |  | 
|  | // 0+1+2, 3+4+5 | 
|  | "add       v16.8h, v16.8h, v0.8h                   \n" | 
|  | "add       v17.8h, v17.8h, v4.8h                   \n" | 
|  |  | 
|  | // Need to divide, but can't downshift as the the value | 
|  | //  isn't a power of 2. So multiply by 65536 / n | 
|  | //  and take the upper 16 bits. | 
|  | "sqrdmulh  v0.8h, v16.8h, v30.8h                   \n" | 
|  | "sqrdmulh  v1.8h, v17.8h, v30.8h                   \n" | 
|  |  | 
|  | // Align for table lookup, vtbl requires registers to | 
|  | //  be adjacent | 
|  |  | 
|  | "tbl       v3.16b, {v0.16b, v1.16b, v2.16b}, v31.16b \n" | 
|  |  | 
|  | MEMACCESS(1) | 
|  | "st1       {v3.8b}, [%1], #8                       \n" | 
|  | MEMACCESS(1) | 
|  | "st1       {v3.s}[2], [%1], #4                     \n" | 
|  | "b.gt      1b                                      \n" | 
|  | : "+r"(src_ptr),         // %0 | 
|  | "+r"(dst_ptr),         // %1 | 
|  | "+r"(tmp_src_stride),  // %2 | 
|  | "+r"(dst_width)        // %3 | 
|  | : "r"(&kMult38_Div6),    // %4 | 
|  | "r"(&kShuf38_2)        // %5 | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16", "v17", | 
|  | "v18", "v19", "v30", "v31", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleAddRows_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint16* dst_ptr, int src_width, int src_height) { | 
|  | const uint8* src_tmp = NULL; | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | "mov       %0, %1                          \n" | 
|  | "mov       w12, %w5                        \n" | 
|  | "eor       v2.16b, v2.16b, v2.16b          \n" | 
|  | "eor       v3.16b, v3.16b, v3.16b          \n" | 
|  | "2:                                          \n" | 
|  | // load 16 pixels into q0 | 
|  | MEMACCESS(0) | 
|  | "ld1       {v0.16b}, [%0], %3              \n" | 
|  | "uaddw2    v3.8h, v3.8h, v0.16b            \n" | 
|  | "uaddw     v2.8h, v2.8h, v0.8b             \n" | 
|  | "subs      w12, w12, #1                    \n" | 
|  | "b.gt      2b                              \n" | 
|  | MEMACCESS(2) | 
|  | "st1      {v2.8h, v3.8h}, [%2], #32        \n"  // store pixels | 
|  | "add      %1, %1, #16                      \n" | 
|  | "subs     %w4, %w4, #16                    \n"  // 16 processed per loop | 
|  | "b.gt     1b                               \n" | 
|  | : "+r"(src_tmp),          // %0 | 
|  | "+r"(src_ptr),          // %1 | 
|  | "+r"(dst_ptr),          // %2 | 
|  | "+r"(src_stride),       // %3 | 
|  | "+r"(src_width),        // %4 | 
|  | "+r"(src_height)        // %5 | 
|  | : | 
|  | : "memory", "cc", "w12", "v0", "v1", "v2", "v3"  // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | // TODO(Yang Zhang): Investigate less load instructions for | 
|  | // the x/dx stepping | 
|  | #define LOAD2_DATA8_LANE(n)                                    \ | 
|  | "lsr        %5, %3, #16                    \n"             \ | 
|  | "add        %6, %1, %5                    \n"              \ | 
|  | "add        %3, %3, %4                     \n"             \ | 
|  | MEMACCESS(6)                                               \ | 
|  | "ld2        {v4.b, v5.b}["#n"], [%6]      \n" | 
|  |  | 
|  | void ScaleFilterCols_NEON(uint8* dst_ptr, const uint8* src_ptr, | 
|  | int dst_width, int x, int dx) { | 
|  | int dx_offset[4] = {0, 1, 2, 3}; | 
|  | int* tmp = dx_offset; | 
|  | const uint8* src_tmp = src_ptr; | 
|  | int64 dst_width64 = (int64) dst_width;  // Work around ios 64 bit warning. | 
|  | int64 x64 = (int64) x; | 
|  | int64 dx64 = (int64) dx; | 
|  | asm volatile ( | 
|  | "dup        v0.4s, %w3                     \n"  // x | 
|  | "dup        v1.4s, %w4                     \n"  // dx | 
|  | "ld1        {v2.4s}, [%5]                  \n"  // 0 1 2 3 | 
|  | "shl        v3.4s, v1.4s, #2               \n"  // 4 * dx | 
|  | "mul        v1.4s, v1.4s, v2.4s            \n" | 
|  | // x         , x + 1 * dx, x + 2 * dx, x + 3 * dx | 
|  | "add        v1.4s, v1.4s, v0.4s            \n" | 
|  | // x + 4 * dx, x + 5 * dx, x + 6 * dx, x + 7 * dx | 
|  | "add        v2.4s, v1.4s, v3.4s            \n" | 
|  | "shl        v0.4s, v3.4s, #1               \n"  // 8 * dx | 
|  | "1:                                          \n" | 
|  | LOAD2_DATA8_LANE(0) | 
|  | LOAD2_DATA8_LANE(1) | 
|  | LOAD2_DATA8_LANE(2) | 
|  | LOAD2_DATA8_LANE(3) | 
|  | LOAD2_DATA8_LANE(4) | 
|  | LOAD2_DATA8_LANE(5) | 
|  | LOAD2_DATA8_LANE(6) | 
|  | LOAD2_DATA8_LANE(7) | 
|  | "mov       v6.16b, v1.16b                  \n" | 
|  | "mov       v7.16b, v2.16b                  \n" | 
|  | "uzp1      v6.8h, v6.8h, v7.8h             \n" | 
|  | "ushll     v4.8h, v4.8b, #0                \n" | 
|  | "ushll     v5.8h, v5.8b, #0                \n" | 
|  | "ssubl     v16.4s, v5.4h, v4.4h            \n" | 
|  | "ssubl2    v17.4s, v5.8h, v4.8h            \n" | 
|  | "ushll     v7.4s, v6.4h, #0                \n" | 
|  | "ushll2    v6.4s, v6.8h, #0                \n" | 
|  | "mul       v16.4s, v16.4s, v7.4s           \n" | 
|  | "mul       v17.4s, v17.4s, v6.4s           \n" | 
|  | "shrn      v6.4h, v16.4s, #16              \n" | 
|  | "shrn2     v6.8h, v17.4s, #16              \n" | 
|  | "add       v4.8h, v4.8h, v6.8h             \n" | 
|  | "xtn       v4.8b, v4.8h                    \n" | 
|  |  | 
|  | MEMACCESS(0) | 
|  | "st1       {v4.8b}, [%0], #8               \n"  // store pixels | 
|  | "add       v1.4s, v1.4s, v0.4s             \n" | 
|  | "add       v2.4s, v2.4s, v0.4s             \n" | 
|  | "subs      %w2, %w2, #8                    \n"  // 8 processed per loop | 
|  | "b.gt      1b                              \n" | 
|  | : "+r"(dst_ptr),          // %0 | 
|  | "+r"(src_ptr),          // %1 | 
|  | "+r"(dst_width64),      // %2 | 
|  | "+r"(x64),              // %3 | 
|  | "+r"(dx64),             // %4 | 
|  | "+r"(tmp),              // %5 | 
|  | "+r"(src_tmp)           // %6 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3", | 
|  | "v4", "v5", "v6", "v7", "v16", "v17" | 
|  | ); | 
|  | } | 
|  |  | 
|  | #undef LOAD2_DATA8_LANE | 
|  |  | 
|  | // 16x2 -> 16x1 | 
|  | void ScaleFilterRows_NEON(uint8* dst_ptr, | 
|  | const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | int dst_width, int source_y_fraction) { | 
|  | int y_fraction = 256 - source_y_fraction; | 
|  | asm volatile ( | 
|  | "cmp          %w4, #0                      \n" | 
|  | "b.eq         100f                         \n" | 
|  | "add          %2, %2, %1                   \n" | 
|  | "cmp          %w4, #64                     \n" | 
|  | "b.eq         75f                          \n" | 
|  | "cmp          %w4, #128                    \n" | 
|  | "b.eq         50f                          \n" | 
|  | "cmp          %w4, #192                    \n" | 
|  | "b.eq         25f                          \n" | 
|  |  | 
|  | "dup          v5.8b, %w4                   \n" | 
|  | "dup          v4.8b, %w5                   \n" | 
|  | // General purpose row blend. | 
|  | "1:                                          \n" | 
|  | MEMACCESS(1) | 
|  | "ld1          {v0.16b}, [%1], #16          \n" | 
|  | MEMACCESS(2) | 
|  | "ld1          {v1.16b}, [%2], #16          \n" | 
|  | "subs         %w3, %w3, #16                \n" | 
|  | "umull        v6.8h, v0.8b, v4.8b          \n" | 
|  | "umull2       v7.8h, v0.16b, v4.16b        \n" | 
|  | "umlal        v6.8h, v1.8b, v5.8b          \n" | 
|  | "umlal2       v7.8h, v1.16b, v5.16b        \n" | 
|  | "rshrn        v0.8b, v6.8h, #8             \n" | 
|  | "rshrn2       v0.16b, v7.8h, #8            \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.16b}, [%0], #16          \n" | 
|  | "b.gt         1b                           \n" | 
|  | "b            99f                          \n" | 
|  |  | 
|  | // Blend 25 / 75. | 
|  | "25:                                         \n" | 
|  | MEMACCESS(1) | 
|  | "ld1          {v0.16b}, [%1], #16          \n" | 
|  | MEMACCESS(2) | 
|  | "ld1          {v1.16b}, [%2], #16          \n" | 
|  | "subs         %w3, %w3, #16                \n" | 
|  | "urhadd       v0.16b, v0.16b, v1.16b       \n" | 
|  | "urhadd       v0.16b, v0.16b, v1.16b       \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.16b}, [%0], #16          \n" | 
|  | "b.gt         25b                          \n" | 
|  | "b            99f                          \n" | 
|  |  | 
|  | // Blend 50 / 50. | 
|  | "50:                                         \n" | 
|  | MEMACCESS(1) | 
|  | "ld1          {v0.16b}, [%1], #16          \n" | 
|  | MEMACCESS(2) | 
|  | "ld1          {v1.16b}, [%2], #16          \n" | 
|  | "subs         %w3, %w3, #16                \n" | 
|  | "urhadd       v0.16b, v0.16b, v1.16b       \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.16b}, [%0], #16          \n" | 
|  | "b.gt         50b                          \n" | 
|  | "b            99f                          \n" | 
|  |  | 
|  | // Blend 75 / 25. | 
|  | "75:                                         \n" | 
|  | MEMACCESS(1) | 
|  | "ld1          {v1.16b}, [%1], #16          \n" | 
|  | MEMACCESS(2) | 
|  | "ld1          {v0.16b}, [%2], #16          \n" | 
|  | "subs         %w3, %w3, #16                \n" | 
|  | "urhadd       v0.16b, v0.16b, v1.16b       \n" | 
|  | "urhadd       v0.16b, v0.16b, v1.16b       \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.16b}, [%0], #16          \n" | 
|  | "b.gt         75b                          \n" | 
|  | "b            99f                          \n" | 
|  |  | 
|  | // Blend 100 / 0 - Copy row unchanged. | 
|  | "100:                                        \n" | 
|  | MEMACCESS(1) | 
|  | "ld1          {v0.16b}, [%1], #16          \n" | 
|  | "subs         %w3, %w3, #16                \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.16b}, [%0], #16          \n" | 
|  | "b.gt         100b                         \n" | 
|  |  | 
|  | "99:                                         \n" | 
|  | MEMACCESS(0) | 
|  | "st1          {v0.b}[15], [%0]             \n" | 
|  | : "+r"(dst_ptr),          // %0 | 
|  | "+r"(src_ptr),          // %1 | 
|  | "+r"(src_stride),       // %2 | 
|  | "+r"(dst_width),        // %3 | 
|  | "+r"(source_y_fraction),// %4 | 
|  | "+r"(y_fraction)        // %5 | 
|  | : | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "memory", "cc" | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleARGBRowDown2_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | // load even pixels into q0, odd into q1 | 
|  | MEMACCESS (0) | 
|  | "ld2        {v0.4s, v1.4s}, [%0], #32      \n" | 
|  | MEMACCESS (0) | 
|  | "ld2        {v2.4s, v3.4s}, [%0], #32      \n" | 
|  | "subs       %w2, %w2, #8                   \n"  // 8 processed per loop | 
|  | MEMACCESS (1) | 
|  | "st1        {v1.16b}, [%1], #16            \n"  // store odd pixels | 
|  | MEMACCESS (1) | 
|  | "st1        {v3.16b}, [%1], #16            \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r" (src_ptr),          // %0 | 
|  | "+r" (dst),              // %1 | 
|  | "+r" (dst_width)         // %2 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3"  // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleARGBRowDown2Linear_NEON(const uint8* src_argb, ptrdiff_t src_stride, | 
|  | uint8* dst_argb, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | MEMACCESS (0) | 
|  | // load 8 ARGB pixels. | 
|  | "ld4        {v0.16b,v1.16b,v2.16b,v3.16b}, [%0], #64   \n" | 
|  | "subs       %w2, %w2, #8                   \n"  // 8 processed per loop. | 
|  | "uaddlp     v0.8h, v0.16b                  \n"  // B 16 bytes -> 8 shorts. | 
|  | "uaddlp     v1.8h, v1.16b                  \n"  // G 16 bytes -> 8 shorts. | 
|  | "uaddlp     v2.8h, v2.16b                  \n"  // R 16 bytes -> 8 shorts. | 
|  | "uaddlp     v3.8h, v3.16b                  \n"  // A 16 bytes -> 8 shorts. | 
|  | "rshrn      v0.8b, v0.8h, #1               \n"  // downshift, round and pack | 
|  | "rshrn      v1.8b, v1.8h, #1               \n" | 
|  | "rshrn      v2.8b, v2.8h, #1               \n" | 
|  | "rshrn      v3.8b, v3.8h, #1               \n" | 
|  | MEMACCESS (1) | 
|  | "st4        {v0.8b,v1.8b,v2.8b,v3.8b}, [%1], #32     \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_argb),         // %0 | 
|  | "+r"(dst_argb),         // %1 | 
|  | "+r"(dst_width)         // %2 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3"    // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleARGBRowDown2Box_NEON(const uint8* src_ptr, ptrdiff_t src_stride, | 
|  | uint8* dst, int dst_width) { | 
|  | asm volatile ( | 
|  | // change the stride to row 2 pointer | 
|  | "add        %1, %1, %0                     \n" | 
|  | "1:                                          \n" | 
|  | MEMACCESS (0) | 
|  | "ld4        {v0.16b,v1.16b,v2.16b,v3.16b}, [%0], #64   \n"  // load 8 ARGB pixels. | 
|  | "subs       %w3, %w3, #8                   \n"  // 8 processed per loop. | 
|  | "uaddlp     v0.8h, v0.16b                  \n"  // B 16 bytes -> 8 shorts. | 
|  | "uaddlp     v1.8h, v1.16b                  \n"  // G 16 bytes -> 8 shorts. | 
|  | "uaddlp     v2.8h, v2.16b                  \n"  // R 16 bytes -> 8 shorts. | 
|  | "uaddlp     v3.8h, v3.16b                  \n"  // A 16 bytes -> 8 shorts. | 
|  | MEMACCESS (1) | 
|  | "ld4        {v16.16b,v17.16b,v18.16b,v19.16b}, [%1], #64 \n"  // load 8 more ARGB pixels. | 
|  | "uadalp     v0.8h, v16.16b                 \n"  // B 16 bytes -> 8 shorts. | 
|  | "uadalp     v1.8h, v17.16b                 \n"  // G 16 bytes -> 8 shorts. | 
|  | "uadalp     v2.8h, v18.16b                 \n"  // R 16 bytes -> 8 shorts. | 
|  | "uadalp     v3.8h, v19.16b                 \n"  // A 16 bytes -> 8 shorts. | 
|  | "rshrn      v0.8b, v0.8h, #2               \n"  // downshift, round and pack | 
|  | "rshrn      v1.8b, v1.8h, #2               \n" | 
|  | "rshrn      v2.8b, v2.8h, #2               \n" | 
|  | "rshrn      v3.8b, v3.8h, #2               \n" | 
|  | MEMACCESS (2) | 
|  | "st4        {v0.8b,v1.8b,v2.8b,v3.8b}, [%2], #32     \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r" (src_ptr),          // %0 | 
|  | "+r" (src_stride),       // %1 | 
|  | "+r" (dst),              // %2 | 
|  | "+r" (dst_width)         // %3 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3", "v16", "v17", "v18", "v19" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Reads 4 pixels at a time. | 
|  | // Alignment requirement: src_argb 4 byte aligned. | 
|  | void ScaleARGBRowDownEven_NEON(const uint8* src_argb,  ptrdiff_t src_stride, | 
|  | int src_stepx, uint8* dst_argb, int dst_width) { | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.s}[0], [%0], %3            \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.s}[1], [%0], %3            \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.s}[2], [%0], %3            \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.s}[3], [%0], %3            \n" | 
|  | "subs       %w2, %w2, #4                   \n"  // 4 pixels per loop. | 
|  | MEMACCESS(1) | 
|  | "st1        {v0.16b}, [%1], #16            \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_argb),    // %0 | 
|  | "+r"(dst_argb),    // %1 | 
|  | "+r"(dst_width)    // %2 | 
|  | : "r"((int64)(src_stepx * 4)) // %3 | 
|  | : "memory", "cc", "v0" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Reads 4 pixels at a time. | 
|  | // Alignment requirement: src_argb 4 byte aligned. | 
|  | // TODO(Yang Zhang): Might be worth another optimization pass in future. | 
|  | // It could be upgraded to 8 pixels at a time to start with. | 
|  | void ScaleARGBRowDownEvenBox_NEON(const uint8* src_argb, ptrdiff_t src_stride, | 
|  | int src_stepx, | 
|  | uint8* dst_argb, int dst_width) { | 
|  | asm volatile ( | 
|  | "add        %1, %1, %0                     \n" | 
|  | "1:                                          \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v0.8b}, [%0], %4              \n"  // Read 4 2x2 blocks -> 2x1 | 
|  | MEMACCESS(1) | 
|  | "ld1        {v1.8b}, [%1], %4              \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v2.8b}, [%0], %4              \n" | 
|  | MEMACCESS(1) | 
|  | "ld1        {v3.8b}, [%1], %4              \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v4.8b}, [%0], %4              \n" | 
|  | MEMACCESS(1) | 
|  | "ld1        {v5.8b}, [%1], %4              \n" | 
|  | MEMACCESS(0) | 
|  | "ld1        {v6.8b}, [%0], %4              \n" | 
|  | MEMACCESS(1) | 
|  | "ld1        {v7.8b}, [%1], %4              \n" | 
|  | "uaddl      v0.8h, v0.8b, v1.8b            \n" | 
|  | "uaddl      v2.8h, v2.8b, v3.8b            \n" | 
|  | "uaddl      v4.8h, v4.8b, v5.8b            \n" | 
|  | "uaddl      v6.8h, v6.8b, v7.8b            \n" | 
|  | "mov        v16.d[1], v0.d[1]              \n"  // ab_cd -> ac_bd | 
|  | "mov        v0.d[1], v2.d[0]               \n" | 
|  | "mov        v2.d[0], v16.d[1]              \n" | 
|  | "mov        v16.d[1], v4.d[1]              \n"  // ef_gh -> eg_fh | 
|  | "mov        v4.d[1], v6.d[0]               \n" | 
|  | "mov        v6.d[0], v16.d[1]              \n" | 
|  | "add        v0.8h, v0.8h, v2.8h            \n"  // (a+b)_(c+d) | 
|  | "add        v4.8h, v4.8h, v6.8h            \n"  // (e+f)_(g+h) | 
|  | "rshrn      v0.8b, v0.8h, #2               \n"  // first 2 pixels. | 
|  | "rshrn2     v0.16b, v4.8h, #2              \n"  // next 2 pixels. | 
|  | "subs       %w3, %w3, #4                   \n"  // 4 pixels per loop. | 
|  | MEMACCESS(2) | 
|  | "st1     {v0.16b}, [%2], #16               \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_argb),    // %0 | 
|  | "+r"(src_stride),  // %1 | 
|  | "+r"(dst_argb),    // %2 | 
|  | "+r"(dst_width)    // %3 | 
|  | : "r"((int64)(src_stepx * 4)) // %4 | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16" | 
|  | ); | 
|  | } | 
|  |  | 
|  | // TODO(Yang Zhang): Investigate less load instructions for | 
|  | // the x/dx stepping | 
|  | #define LOAD1_DATA32_LANE(vn, n)                               \ | 
|  | "lsr        %5, %3, #16                    \n"             \ | 
|  | "add        %6, %1, %5, lsl #2             \n"             \ | 
|  | "add        %3, %3, %4                     \n"             \ | 
|  | MEMACCESS(6)                                               \ | 
|  | "ld1        {"#vn".s}["#n"], [%6]          \n" | 
|  |  | 
|  | void ScaleARGBCols_NEON(uint8* dst_argb, const uint8* src_argb, | 
|  | int dst_width, int x, int dx) { | 
|  | const uint8* src_tmp = src_argb; | 
|  | int64 dst_width64 = (int64) dst_width;  // Work around ios 64 bit warning. | 
|  | int64 x64 = (int64) x; | 
|  | int64 dx64 = (int64) dx; | 
|  | int64 tmp64 = 0; | 
|  | asm volatile ( | 
|  | "1:                                          \n" | 
|  | LOAD1_DATA32_LANE(v0, 0) | 
|  | LOAD1_DATA32_LANE(v0, 1) | 
|  | LOAD1_DATA32_LANE(v0, 2) | 
|  | LOAD1_DATA32_LANE(v0, 3) | 
|  | LOAD1_DATA32_LANE(v1, 0) | 
|  | LOAD1_DATA32_LANE(v1, 1) | 
|  | LOAD1_DATA32_LANE(v1, 2) | 
|  | LOAD1_DATA32_LANE(v1, 3) | 
|  |  | 
|  | MEMACCESS(0) | 
|  | "st1        {v0.4s, v1.4s}, [%0], #32      \n"  // store pixels | 
|  | "subs       %w2, %w2, #8                   \n"  // 8 processed per loop | 
|  | "b.gt        1b                            \n" | 
|  | : "+r"(dst_argb),         // %0 | 
|  | "+r"(src_argb),         // %1 | 
|  | "+r"(dst_width64),      // %2 | 
|  | "+r"(x64),              // %3 | 
|  | "+r"(dx64),             // %4 | 
|  | "+r"(tmp64),            // %5 | 
|  | "+r"(src_tmp)           // %6 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1" | 
|  | ); | 
|  | } | 
|  |  | 
|  | #undef LOAD1_DATA32_LANE | 
|  |  | 
|  | // TODO(Yang Zhang): Investigate less load instructions for | 
|  | // the x/dx stepping | 
|  | #define LOAD2_DATA32_LANE(vn1, vn2, n)                         \ | 
|  | "lsr        %5, %3, #16                           \n"      \ | 
|  | "add        %6, %1, %5, lsl #2                    \n"      \ | 
|  | "add        %3, %3, %4                            \n"      \ | 
|  | MEMACCESS(6)                                               \ | 
|  | "ld2        {"#vn1".s, "#vn2".s}["#n"], [%6]      \n" | 
|  |  | 
|  | void ScaleARGBFilterCols_NEON(uint8* dst_argb, const uint8* src_argb, | 
|  | int dst_width, int x, int dx) { | 
|  | int dx_offset[4] = {0, 1, 2, 3}; | 
|  | int* tmp = dx_offset; | 
|  | const uint8* src_tmp = src_argb; | 
|  | int64 dst_width64 = (int64) dst_width;  // Work around ios 64 bit warning. | 
|  | int64 x64 = (int64) x; | 
|  | int64 dx64 = (int64) dx; | 
|  | asm volatile ( | 
|  | "dup        v0.4s, %w3                     \n"  // x | 
|  | "dup        v1.4s, %w4                     \n"  // dx | 
|  | "ld1        {v2.4s}, [%5]                  \n"  // 0 1 2 3 | 
|  | "shl        v6.4s, v1.4s, #2               \n"  // 4 * dx | 
|  | "mul        v1.4s, v1.4s, v2.4s            \n" | 
|  | "movi       v3.16b, #0x7f                  \n"  // 0x7F | 
|  | "movi       v4.8h, #0x7f                   \n"  // 0x7F | 
|  | // x         , x + 1 * dx, x + 2 * dx, x + 3 * dx | 
|  | "add        v5.4s, v1.4s, v0.4s            \n" | 
|  | "1:                                          \n" | 
|  | // d0, d1: a | 
|  | // d2, d3: b | 
|  | LOAD2_DATA32_LANE(v0, v1, 0) | 
|  | LOAD2_DATA32_LANE(v0, v1, 1) | 
|  | LOAD2_DATA32_LANE(v0, v1, 2) | 
|  | LOAD2_DATA32_LANE(v0, v1, 3) | 
|  | "shrn       v2.4h, v5.4s, #9               \n" | 
|  | "and        v2.8b, v2.8b, v4.8b            \n" | 
|  | "dup        v16.8b, v2.b[0]                \n" | 
|  | "dup        v17.8b, v2.b[2]                \n" | 
|  | "dup        v18.8b, v2.b[4]                \n" | 
|  | "dup        v19.8b, v2.b[6]                \n" | 
|  | "ext        v2.8b, v16.8b, v17.8b, #4      \n" | 
|  | "ext        v17.8b, v18.8b, v19.8b, #4     \n" | 
|  | "ins        v2.d[1], v17.d[0]              \n"  // f | 
|  | "eor        v7.16b, v2.16b, v3.16b         \n"  // 0x7f ^ f | 
|  | "umull      v16.8h, v0.8b, v7.8b           \n" | 
|  | "umull2     v17.8h, v0.16b, v7.16b         \n" | 
|  | "umull      v18.8h, v1.8b, v2.8b           \n" | 
|  | "umull2     v19.8h, v1.16b, v2.16b         \n" | 
|  | "add        v16.8h, v16.8h, v18.8h         \n" | 
|  | "add        v17.8h, v17.8h, v19.8h         \n" | 
|  | "shrn       v0.8b, v16.8h, #7              \n" | 
|  | "shrn2      v0.16b, v17.8h, #7             \n" | 
|  |  | 
|  | MEMACCESS(0) | 
|  | "st1     {v0.4s}, [%0], #16                \n"  // store pixels | 
|  | "add     v5.4s, v5.4s, v6.4s               \n" | 
|  | "subs    %w2, %w2, #4                      \n"  // 4 processed per loop | 
|  | "b.gt    1b                                \n" | 
|  | : "+r"(dst_argb),         // %0 | 
|  | "+r"(src_argb),         // %1 | 
|  | "+r"(dst_width64),      // %2 | 
|  | "+r"(x64),              // %3 | 
|  | "+r"(dx64),             // %4 | 
|  | "+r"(tmp),              // %5 | 
|  | "+r"(src_tmp)           // %6 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3", "v4", "v5", | 
|  | "v6", "v7", "v16", "v17", "v18", "v19" | 
|  | ); | 
|  | } | 
|  |  | 
|  | #undef LOAD2_DATA32_LANE | 
|  |  | 
|  | #endif  // !defined(LIBYUV_DISABLE_NEON) && defined(__aarch64__) | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | }  // extern "C" | 
|  | }  // namespace libyuv | 
|  | #endif |