|  | /* | 
|  | *  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/row.h" | 
|  | #include "libyuv/scale.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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | // load even pixels into v0, odd into v1 | 
|  | "ld2         {v0.16b,v1.16b}, [%0], #32    \n" | 
|  | "subs        %w2, %w2, #16                 \n"  // 16 processed per loop | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | // load even pixels into v0, odd into v1 | 
|  | "ld2         {v0.16b,v1.16b}, [%0], #32    \n" | 
|  | "subs        %w2, %w2, #16                 \n"  // 16 processed per loop | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n"  // rounding half add | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | // change the stride to row 2 pointer | 
|  | "add         %1, %1, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.16b, v1.16b}, [%0], #32   \n"  // load row 1 and post inc | 
|  | "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 | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uaddlp      v1.8h, v1.16b                 \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n" | 
|  | "uadalp      v0.8h, v2.16b                 \n"  // += row 2 add adjacent | 
|  | "uadalp      v1.8h, v3.16b                 \n" | 
|  | "rshrn       v0.8b, v0.8h, #2              \n"  // round and pack | 
|  | "rshrn2      v0.16b, v1.8h, #2             \n" | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "ld4         {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32 \n"  // src line 0 | 
|  | "subs        %w2, %w2, #8                  \n"  // 8 processed per loop | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | const uint8_t* src_ptr1 = src_ptr + src_stride; | 
|  | const uint8_t* src_ptr2 = src_ptr + src_stride * 2; | 
|  | const uint8_t* src_ptr3 = src_ptr + src_stride * 3; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.16b}, [%0], #16           \n"  // load up 16x4 | 
|  | "ld1         {v1.16b}, [%2], #16           \n" | 
|  | "ld1         {v2.16b}, [%3], #16           \n" | 
|  | "ld1         {v3.16b}, [%4], #16           \n" | 
|  | "subs        %w5, %w5, #4                  \n" | 
|  | "uaddlp      v0.8h, v0.16b                 \n" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uadalp      v0.8h, v1.16b                 \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \n" | 
|  | "uadalp      v0.8h, v2.16b                 \n" | 
|  | "prfm        pldl1keep, [%3, 448]          \n" | 
|  | "uadalp      v0.8h, v3.16b                 \n" | 
|  | "prfm        pldl1keep, [%4, 448]          \n" | 
|  | "addp        v0.8h, v0.8h, v0.8h           \n" | 
|  | "rshrn       v0.8b, v0.8h, #4              \n"  // divide by 16 w/rounding | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "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 | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | "movi        v20.8b, #3                    \n" | 
|  | "add         %3, %3, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld4         {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32 \n"  // src line 0 | 
|  | "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" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  |  | 
|  | // (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" | 
|  | "prfm        pldl1keep, [%3, 448]          \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" | 
|  |  | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | "movi        v20.8b, #3                    \n" | 
|  | "add         %3, %3, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld4         {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32 \n"  // src line 0 | 
|  | "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" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  |  | 
|  | // 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" | 
|  | "prfm        pldl1keep, [%3, 448]          \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" | 
|  |  | 
|  | "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 const uvec8 kShuf38 = {0,  3,  6,  8,  11, 14, 16, 19, | 
|  | 22, 24, 27, 30, 0,  0,  0,  0}; | 
|  | static const uvec8 kShuf38_2 = {0,  16, 32, 2,  18, 33, 4, 20, | 
|  | 34, 6,  22, 35, 0,  0,  0, 0}; | 
|  | static const vec16 kMult38_Div6 = {65536 / 12, 65536 / 12, 65536 / 12, | 
|  | 65536 / 12, 65536 / 12, 65536 / 12, | 
|  | 65536 / 12, 65536 / 12}; | 
|  | static const 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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "ld1         {v3.16b}, [%3]                \n" | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.16b,v1.16b}, [%0], #32    \n" | 
|  | "subs        %w2, %w2, #12                 \n" | 
|  | "tbl         v2.16b, {v0.16b,v1.16b}, v3.16b \n" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "st1         {v2.8b}, [%1], #8             \n" | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | const uint8_t* src_ptr1 = src_ptr + src_stride * 2; | 
|  | ptrdiff_t tmp_src_stride = src_stride; | 
|  |  | 
|  | asm volatile( | 
|  | "ld1         {v29.8h}, [%5]                \n" | 
|  | "ld1         {v30.16b}, [%6]               \n" | 
|  | "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 | 
|  | "ld4         {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32 \n" | 
|  | "ld4         {v4.8b,v5.8b,v6.8b,v7.8b}, [%2], #32 \n" | 
|  | "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" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  |  | 
|  | // 0+1+2, 3+4+5 | 
|  | "add         v20.8h, v20.8h, v0.8h         \n" | 
|  | "add         v21.8h, v21.8h, v4.8h         \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \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" | 
|  | "prfm        pldl1keep, [%3, 448]          \n" | 
|  |  | 
|  | // Align for table lookup, vtbl requires registers to be adjacent | 
|  | "tbl         v3.16b, {v0.16b, v1.16b, v2.16b}, v30.16b \n" | 
|  |  | 
|  | "st1         {v3.8b}, [%1], #8             \n" | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | // TODO(fbarchard): use src_stride directly for clang 3.5+. | 
|  | ptrdiff_t tmp_src_stride = src_stride; | 
|  | asm volatile( | 
|  | "ld1         {v30.8h}, [%4]                \n" | 
|  | "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 | 
|  | "ld4         {v0.8b,v1.8b,v2.8b,v3.8b}, [%0], #32 \n" | 
|  | "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" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  |  | 
|  | // 0+1+2, 3+4+5 | 
|  | "add         v16.8h, v16.8h, v0.8h         \n" | 
|  | "add         v17.8h, v17.8h, v4.8h         \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \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" | 
|  |  | 
|  | "st1         {v3.8b}, [%1], #8             \n" | 
|  | "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"); | 
|  | } | 
|  |  | 
|  | // Add a row of bytes to a row of shorts.  Used for box filter. | 
|  | // Reads 16 bytes and accumulates to 16 shorts at a time. | 
|  | void ScaleAddRow_NEON(const uint8_t* src_ptr, | 
|  | uint16_t* dst_ptr, | 
|  | int src_width) { | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "ld1         {v1.8h, v2.8h}, [%1]          \n"  // load accumulator | 
|  | "ld1         {v0.16b}, [%0], #16           \n"  // load 16 bytes | 
|  | "uaddw2      v2.8h, v2.8h, v0.16b          \n"  // add | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uaddw       v1.8h, v1.8h, v0.8b           \n" | 
|  | "st1         {v1.8h, v2.8h}, [%1], #32     \n"  // store accumulator | 
|  | "subs        %w2, %w2, #16                 \n"  // 16 processed per loop | 
|  | "b.gt        1b                            \n" | 
|  | : "+r"(src_ptr),   // %0 | 
|  | "+r"(dst_ptr),   // %1 | 
|  | "+r"(src_width)  // %2 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v2"  // 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" \ | 
|  | "ld2        {v4.b, v5.b}[" #n "], [%6]     \n" | 
|  |  | 
|  | // The NEON version mimics this formula (from row_common.cc): | 
|  | // #define BLENDER(a, b, f) (uint8_t)((int)(a) + | 
|  | //    ((((int)((f)) * ((int)(b) - (int)(a))) + 0x8000) >> 16)) | 
|  |  | 
|  | void ScaleFilterCols_NEON(uint8_t* dst_ptr, | 
|  | const uint8_t* src_ptr, | 
|  | int dst_width, | 
|  | int x, | 
|  | int dx) { | 
|  | int dx_offset[4] = {0, 1, 2, 3}; | 
|  | int* tmp = dx_offset; | 
|  | const uint8_t* src_tmp = src_ptr; | 
|  | int64_t x64 = (int64_t)x;    // NOLINT | 
|  | int64_t dx64 = (int64_t)dx;  // NOLINT | 
|  | 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" | 
|  | "rshrn       v6.4h, v16.4s, #16            \n" | 
|  | "rshrn2      v6.8h, v17.4s, #16            \n" | 
|  | "add         v4.8h, v4.8h, v6.8h           \n" | 
|  | "xtn         v4.8b, v4.8h                  \n" | 
|  |  | 
|  | "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_width),        // %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_t* dst_ptr, | 
|  | const uint8_t* 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" | 
|  | "ld1         {v0.16b}, [%1], #16           \n" | 
|  | "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" | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | "umlal       v6.8h, v1.8b, v5.8b           \n" | 
|  | "umlal2      v7.8h, v1.16b, v5.16b         \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \n" | 
|  | "rshrn       v0.8b, v6.8h, #8              \n" | 
|  | "rshrn2      v0.16b, v7.8h, #8             \n" | 
|  | "st1         {v0.16b}, [%0], #16           \n" | 
|  | "b.gt        1b                            \n" | 
|  | "b           99f                           \n" | 
|  |  | 
|  | // Blend 25 / 75. | 
|  | "25:                                       \n" | 
|  | "ld1         {v0.16b}, [%1], #16           \n" | 
|  | "ld1         {v1.16b}, [%2], #16           \n" | 
|  | "subs        %w3, %w3, #16                 \n" | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \n" | 
|  | "st1         {v0.16b}, [%0], #16           \n" | 
|  | "b.gt        25b                           \n" | 
|  | "b           99f                           \n" | 
|  |  | 
|  | // Blend 50 / 50. | 
|  | "50:                                       \n" | 
|  | "ld1         {v0.16b}, [%1], #16           \n" | 
|  | "ld1         {v1.16b}, [%2], #16           \n" | 
|  | "subs        %w3, %w3, #16                 \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \n" | 
|  | "st1         {v0.16b}, [%0], #16           \n" | 
|  | "b.gt        50b                           \n" | 
|  | "b           99f                           \n" | 
|  |  | 
|  | // Blend 75 / 25. | 
|  | "75:                                       \n" | 
|  | "ld1         {v1.16b}, [%1], #16           \n" | 
|  | "ld1         {v0.16b}, [%2], #16           \n" | 
|  | "subs        %w3, %w3, #16                 \n" | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n" | 
|  | "prfm        pldl1keep, [%2, 448]          \n" | 
|  | "st1         {v0.16b}, [%0], #16           \n" | 
|  | "b.gt        75b                           \n" | 
|  | "b           99f                           \n" | 
|  |  | 
|  | // Blend 100 / 0 - Copy row unchanged. | 
|  | "100:                                      \n" | 
|  | "ld1         {v0.16b}, [%1], #16           \n" | 
|  | "subs        %w3, %w3, #16                 \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | "st1         {v0.16b}, [%0], #16           \n" | 
|  | "b.gt        100b                          \n" | 
|  |  | 
|  | "99:                                       \n" | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | // load 16 ARGB pixels with even pixels into q0/q2, odd into q1/q3 | 
|  | "ld4         {v0.4s,v1.4s,v2.4s,v3.4s}, [%0], #64 \n" | 
|  | "subs        %w2, %w2, #8                  \n"  // 8 processed per loop | 
|  | "mov         v2.16b, v3.16b                \n" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "st2         {v1.4s,v2.4s}, [%1], #32      \n"  // store 8 odd pixels | 
|  | "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_t* src_argb, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst_argb, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | // load 16 ARGB pixels with even pixels into q0/q2, odd into q1/q3 | 
|  | "ld4         {v0.4s,v1.4s,v2.4s,v3.4s}, [%0], #64 \n" | 
|  | "subs        %w2, %w2, #8                  \n"  // 8 processed per loop | 
|  |  | 
|  | "urhadd      v0.16b, v0.16b, v1.16b        \n"  // rounding half add | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "urhadd      v1.16b, v2.16b, v3.16b        \n" | 
|  | "st2         {v0.4s,v1.4s}, [%1], #32      \n"  // store 8 pixels | 
|  | "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_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | // change the stride to row 2 pointer | 
|  | "add         %1, %1, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld4         {v0.16b,v1.16b,v2.16b,v3.16b}, [%0], #64 \n"  // load 16 ARGB | 
|  | "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. | 
|  | "ld4         {v16.16b,v17.16b,v18.16b,v19.16b}, [%1], #64 \n"  // load 8 | 
|  | "uadalp      v0.8h, v16.16b                \n"  // B 16 bytes -> 8 shorts. | 
|  | "uadalp      v1.8h, v17.16b                \n"  // G 16 bytes -> 8 shorts. | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uadalp      v2.8h, v18.16b                \n"  // R 16 bytes -> 8 shorts. | 
|  | "uadalp      v3.8h, v19.16b                \n"  // A 16 bytes -> 8 shorts. | 
|  | "prfm        pldl1keep, [%1, 448]          \n" | 
|  | "rshrn       v0.8b, v0.8h, #2              \n"  // round and pack | 
|  | "rshrn       v1.8b, v1.8h, #2              \n" | 
|  | "rshrn       v2.8b, v2.8h, #2              \n" | 
|  | "rshrn       v3.8b, v3.8h, #2              \n" | 
|  | "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_t* src_argb, | 
|  | ptrdiff_t src_stride, | 
|  | int src_stepx, | 
|  | uint8_t* dst_argb, | 
|  | int dst_width) { | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.s}[0], [%0], %3           \n" | 
|  | "ld1         {v0.s}[1], [%0], %3           \n" | 
|  | "ld1         {v0.s}[2], [%0], %3           \n" | 
|  | "ld1         {v0.s}[3], [%0], %3           \n" | 
|  | "subs        %w2, %w2, #4                  \n"  // 4 pixels per loop. | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "st1         {v0.16b}, [%1], #16           \n" | 
|  | "b.gt        1b                            \n" | 
|  | : "+r"(src_argb),                // %0 | 
|  | "+r"(dst_argb),                // %1 | 
|  | "+r"(dst_width)                // %2 | 
|  | : "r"((int64_t)(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_t* src_argb, | 
|  | ptrdiff_t src_stride, | 
|  | int src_stepx, | 
|  | uint8_t* dst_argb, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | "add         %1, %1, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.8b}, [%0], %4             \n"  // Read 4 2x2 -> 2x1 | 
|  | "ld1         {v1.8b}, [%1], %4             \n" | 
|  | "ld1         {v2.8b}, [%0], %4             \n" | 
|  | "ld1         {v3.8b}, [%1], %4             \n" | 
|  | "ld1         {v4.8b}, [%0], %4             \n" | 
|  | "ld1         {v5.8b}, [%1], %4             \n" | 
|  | "ld1         {v6.8b}, [%0], %4             \n" | 
|  | "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" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "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" | 
|  | "prfm        pldl1keep, [%1, 448]          \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. | 
|  | "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_t)(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" \ | 
|  | "ld1        {" #vn ".s}[" #n "], [%6]      \n" | 
|  |  | 
|  | void ScaleARGBCols_NEON(uint8_t* dst_argb, | 
|  | const uint8_t* src_argb, | 
|  | int dst_width, | 
|  | int x, | 
|  | int dx) { | 
|  | const uint8_t* src_tmp = src_argb; | 
|  | int64_t x64 = (int64_t)x;    // NOLINT | 
|  | int64_t dx64 = (int64_t)dx;  // NOLINT | 
|  | int64_t tmp64; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | // clang-format off | 
|  | 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) | 
|  | "prfm        pldl1keep, [%1, 448]          \n"  // prefetch 7 lines ahead | 
|  | // clang-format on | 
|  | "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_width),  // %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" \ | 
|  | "ld2        {" #vn1 ".s, " #vn2 ".s}[" #n "], [%6]  \n" | 
|  |  | 
|  | void ScaleARGBFilterCols_NEON(uint8_t* dst_argb, | 
|  | const uint8_t* src_argb, | 
|  | int dst_width, | 
|  | int x, | 
|  | int dx) { | 
|  | int dx_offset[4] = {0, 1, 2, 3}; | 
|  | int* tmp = dx_offset; | 
|  | const uint8_t* src_tmp = src_argb; | 
|  | int64_t x64 = (int64_t)x;    // NOLINT | 
|  | int64_t dx64 = (int64_t)dx;  // NOLINT | 
|  | 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" | 
|  | "prfm       pldl1keep, [%1, 448]           \n"  // prefetch 7 lines ahead | 
|  | "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" | 
|  | "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_width),        // %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 | 
|  |  | 
|  | // Read 16x2 average down and write 8x1. | 
|  | void ScaleRowDown2Box_16_NEON(const uint16_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint16_t* dst, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | // change the stride to row 2 pointer | 
|  | "add         %1, %0, %1, lsl #1            \n"  // ptr + stide * 2 | 
|  | "1:                                        \n" | 
|  | "ld1         {v0.8h, v1.8h}, [%0], #32     \n"  // load row 1 and post inc | 
|  | "ld1         {v2.8h, v3.8h}, [%1], #32     \n"  // load row 2 and post inc | 
|  | "subs        %w3, %w3, #8                  \n"  // 8 processed per loop | 
|  | "uaddlp      v0.4s, v0.8h                  \n"  // row 1 add adjacent | 
|  | "uaddlp      v1.4s, v1.8h                  \n" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uadalp      v0.4s, v2.8h                  \n"  // +row 2 add adjacent | 
|  | "uadalp      v1.4s, v3.8h                  \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n" | 
|  | "rshrn       v0.4h, v0.4s, #2              \n"  // round and pack | 
|  | "rshrn2      v0.8h, v1.4s, #2              \n" | 
|  | "st1         {v0.8h}, [%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 | 
|  | ); | 
|  | } | 
|  |  | 
|  | // Read 8x2 upsample with filtering and write 16x1. | 
|  | // Actually reads an extra pixel, so 9x2. | 
|  | void ScaleRowUp2_16_NEON(const uint16_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint16_t* dst, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | "add         %1, %0, %1, lsl #1            \n"  // ptr + stide * 2 | 
|  | "movi        v0.8h, #9                     \n"  // constants | 
|  | "movi        v1.4s, #3                     \n" | 
|  |  | 
|  | "1:                                        \n" | 
|  | "ld1         {v3.8h}, [%0], %4             \n"  // TL read first 8 | 
|  | "ld1         {v4.8h}, [%0], %5             \n"  // TR read 8 offset by 1 | 
|  | "ld1         {v5.8h}, [%1], %4             \n"  // BL read 8 from next row | 
|  | "ld1         {v6.8h}, [%1], %5             \n"  // BR offset by 1 | 
|  | "subs        %w3, %w3, #16                 \n"  // 16 dst pixels per loop | 
|  | "umull       v16.4s, v3.4h, v0.4h          \n" | 
|  | "umull2      v7.4s, v3.8h, v0.8h           \n" | 
|  | "umull       v18.4s, v4.4h, v0.4h          \n" | 
|  | "umull2      v17.4s, v4.8h, v0.8h          \n" | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "uaddw       v16.4s, v16.4s, v6.4h         \n" | 
|  | "uaddl2      v19.4s, v6.8h, v3.8h          \n" | 
|  | "uaddl       v3.4s, v6.4h, v3.4h           \n" | 
|  | "uaddw2      v6.4s, v7.4s, v6.8h           \n" | 
|  | "uaddl2      v7.4s, v5.8h, v4.8h           \n" | 
|  | "uaddl       v4.4s, v5.4h, v4.4h           \n" | 
|  | "uaddw       v18.4s, v18.4s, v5.4h         \n" | 
|  | "prfm        pldl1keep, [%1, 448]          \n" | 
|  | "mla         v16.4s, v4.4s, v1.4s          \n" | 
|  | "mla         v18.4s, v3.4s, v1.4s          \n" | 
|  | "mla         v6.4s, v7.4s, v1.4s           \n" | 
|  | "uaddw2      v4.4s, v17.4s, v5.8h          \n" | 
|  | "uqrshrn     v16.4h,  v16.4s, #4           \n" | 
|  | "mla         v4.4s, v19.4s, v1.4s          \n" | 
|  | "uqrshrn2    v16.8h, v6.4s, #4             \n" | 
|  | "uqrshrn     v17.4h, v18.4s, #4            \n" | 
|  | "uqrshrn2    v17.8h, v4.4s, #4             \n" | 
|  | "st2         {v16.8h-v17.8h}, [%2], #32    \n" | 
|  | "b.gt        1b                            \n" | 
|  | : "+r"(src_ptr),     // %0 | 
|  | "+r"(src_stride),  // %1 | 
|  | "+r"(dst),         // %2 | 
|  | "+r"(dst_width)    // %3 | 
|  | : "r"(2LL),          // %4 | 
|  | "r"(14LL)          // %5 | 
|  | : "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16", "v17", "v18", | 
|  | "v19"  // Clobber List | 
|  | ); | 
|  | } | 
|  |  | 
|  | void ScaleUVRowDown2Box_NEON(const uint8_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | uint8_t* dst, | 
|  | int dst_width) { | 
|  | asm volatile( | 
|  | // change the stride to row 2 pointer | 
|  | "add         %1, %1, %0                    \n" | 
|  | "1:                                        \n" | 
|  | "ld2         {v0.16b,v1.16b}, [%0], #32    \n"  // load 16 UV | 
|  | "subs        %w3, %w3, #8                  \n"  // 8 processed per loop. | 
|  | "uaddlp      v0.8h, v0.16b                 \n"  // U 16 bytes -> 8 shorts. | 
|  | "uaddlp      v1.8h, v1.16b                 \n"  // V 16 bytes -> 8 shorts. | 
|  | "ld2         {v16.16b,v17.16b}, [%1], #32  \n"  // load 16 | 
|  | "uadalp      v0.8h, v16.16b                \n"  // U 16 bytes -> 8 shorts. | 
|  | "uadalp      v1.8h, v17.16b                \n"  // V 16 bytes -> 8 shorts. | 
|  | "prfm        pldl1keep, [%0, 448]          \n"  // prefetch 7 lines ahead | 
|  | "rshrn       v0.8b, v0.8h, #2              \n"  // round and pack | 
|  | "prfm        pldl1keep, [%1, 448]          \n" | 
|  | "rshrn       v1.8b, v1.8h, #2              \n" | 
|  | "st2         {v0.8b,v1.8b}, [%2], #16      \n" | 
|  | "b.gt        1b                            \n" | 
|  | : "+r"(src_ptr),     // %0 | 
|  | "+r"(src_stride),  // %1 | 
|  | "+r"(dst),         // %2 | 
|  | "+r"(dst_width)    // %3 | 
|  | : | 
|  | : "memory", "cc", "v0", "v1", "v16", "v17"); | 
|  | } | 
|  |  | 
|  | // Reads 4 pixels at a time. | 
|  | void ScaleUVRowDownEven_NEON(const uint8_t* src_ptr, | 
|  | ptrdiff_t src_stride, | 
|  | int src_stepx,  // pixel step | 
|  | uint8_t* dst_ptr, | 
|  | int dst_width) { | 
|  | const uint8_t* src1_ptr = src_ptr + src_stepx * 2; | 
|  | const uint8_t* src2_ptr = src_ptr + src_stepx * 4; | 
|  | const uint8_t* src3_ptr = src_ptr + src_stepx * 6; | 
|  | (void)src_stride; | 
|  | asm volatile( | 
|  | "1:                                        \n" | 
|  | "ld1        {v0.h}[0], [%0], %6            \n" | 
|  | "ld1        {v1.h}[0], [%1], %6            \n" | 
|  | "ld1        {v2.h}[0], [%2], %6            \n" | 
|  | "ld1        {v3.h}[0], [%3], %6            \n" | 
|  | "subs       %w5, %w5, #4                   \n"  // 4 pixels per loop. | 
|  | "st4        {v0.h, v1.h, v2.h, v3.h}[0], [%4], #8 \n" | 
|  | "b.gt       1b                             \n" | 
|  | : "+r"(src_ptr),                 // %0 | 
|  | "+r"(src1_ptr),                // %1 | 
|  | "+r"(src2_ptr),                // %2 | 
|  | "+r"(src3_ptr),                // %3 | 
|  | "+r"(dst_ptr),                 // %4 | 
|  | "+r"(dst_width)                // %5 | 
|  | : "r"((int64_t)(src_stepx * 8))  // %6 | 
|  | : "memory", "cc", "v0", "v1", "v2", "v3"); | 
|  | } | 
|  |  | 
|  | #endif  // !defined(LIBYUV_DISABLE_NEON) && defined(__aarch64__) | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | }  // extern "C" | 
|  | }  // namespace libyuv | 
|  | #endif |