1 // Copyright 2014 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 //  NEON common code.
11 
12 #ifndef WEBP_DSP_NEON_H_
13 #define WEBP_DSP_NEON_H_
14 
15 #include <arm_neon.h>
16 
17 #include "src/dsp/dsp.h"
18 
19 // Right now, some intrinsics functions seem slower, so we disable them
20 // everywhere except newer clang/gcc or aarch64 where the inline assembly is
21 // incompatible.
22 #if LOCAL_CLANG_PREREQ(3,8) || LOCAL_GCC_PREREQ(4,9) || defined(__aarch64__)
23 #define WEBP_USE_INTRINSICS   // use intrinsics when possible
24 #endif
25 
26 #define INIT_VECTOR2(v, a, b) do {  \
27   v.val[0] = a;                     \
28   v.val[1] = b;                     \
29 } while (0)
30 
31 #define INIT_VECTOR3(v, a, b, c) do {  \
32   v.val[0] = a;                        \
33   v.val[1] = b;                        \
34   v.val[2] = c;                        \
35 } while (0)
36 
37 #define INIT_VECTOR4(v, a, b, c, d) do {  \
38   v.val[0] = a;                           \
39   v.val[1] = b;                           \
40   v.val[2] = c;                           \
41   v.val[3] = d;                           \
42 } while (0)
43 
44 // if using intrinsics, this flag avoids some functions that make gcc-4.6.3
45 // crash ("internal compiler error: in immed_double_const, at emit-rtl.").
46 // (probably similar to gcc.gnu.org/bugzilla/show_bug.cgi?id=48183)
47 #if !(LOCAL_CLANG_PREREQ(3,8) || LOCAL_GCC_PREREQ(4,8) || defined(__aarch64__))
48 #define WORK_AROUND_GCC
49 #endif
50 
Transpose4x4_NEON(const int32x4x4_t rows)51 static WEBP_INLINE int32x4x4_t Transpose4x4_NEON(const int32x4x4_t rows) {
52   uint64x2x2_t row01, row23;
53 
54   row01.val[0] = vreinterpretq_u64_s32(rows.val[0]);
55   row01.val[1] = vreinterpretq_u64_s32(rows.val[1]);
56   row23.val[0] = vreinterpretq_u64_s32(rows.val[2]);
57   row23.val[1] = vreinterpretq_u64_s32(rows.val[3]);
58   // Transpose 64-bit values (there's no vswp equivalent)
59   {
60     const uint64x1_t row0h = vget_high_u64(row01.val[0]);
61     const uint64x1_t row2l = vget_low_u64(row23.val[0]);
62     const uint64x1_t row1h = vget_high_u64(row01.val[1]);
63     const uint64x1_t row3l = vget_low_u64(row23.val[1]);
64     row01.val[0] = vcombine_u64(vget_low_u64(row01.val[0]), row2l);
65     row23.val[0] = vcombine_u64(row0h, vget_high_u64(row23.val[0]));
66     row01.val[1] = vcombine_u64(vget_low_u64(row01.val[1]), row3l);
67     row23.val[1] = vcombine_u64(row1h, vget_high_u64(row23.val[1]));
68   }
69   {
70     const int32x4x2_t out01 = vtrnq_s32(vreinterpretq_s32_u64(row01.val[0]),
71                                         vreinterpretq_s32_u64(row01.val[1]));
72     const int32x4x2_t out23 = vtrnq_s32(vreinterpretq_s32_u64(row23.val[0]),
73                                         vreinterpretq_s32_u64(row23.val[1]));
74     int32x4x4_t out;
75     out.val[0] = out01.val[0];
76     out.val[1] = out01.val[1];
77     out.val[2] = out23.val[0];
78     out.val[3] = out23.val[1];
79     return out;
80   }
81 }
82 
83 #if 0     // Useful debug macro.
84 #include <stdio.h>
85 #define PRINT_REG(REG, SIZE) do {                       \
86   int i;                                                \
87   printf("%s \t[%d]: 0x", #REG, SIZE);                  \
88   if (SIZE == 8) {                                      \
89     uint8_t _tmp[8];                                    \
90     vst1_u8(_tmp, (REG));                               \
91     for (i = 0; i < 8; ++i) printf("%.2x ", _tmp[i]);   \
92   } else if (SIZE == 16) {                              \
93     uint16_t _tmp[4];                                   \
94     vst1_u16(_tmp, (REG));                              \
95     for (i = 0; i < 4; ++i) printf("%.4x ", _tmp[i]);   \
96   }                                                     \
97   printf("\n");                                         \
98 } while (0)
99 #endif
100 
101 #endif  // WEBP_DSP_NEON_H_
102