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 | // Endian related functions. |
11 | |
12 | #ifndef WEBP_UTILS_ENDIAN_INL_UTILS_H_ |
13 | #define WEBP_UTILS_ENDIAN_INL_UTILS_H_ |
14 | |
15 | #ifdef HAVE_CONFIG_H |
16 | #include "src/webp/config.h" |
17 | #endif |
18 | |
19 | #include "src/dsp/dsp.h" |
20 | #include "src/webp/types.h" |
21 | |
22 | #if defined(WORDS_BIGENDIAN) |
23 | #define HToLE32 BSwap32 |
24 | #define HToLE16 BSwap16 |
25 | #else |
26 | #define HToLE32(x) (x) |
27 | #define HToLE16(x) (x) |
28 | #endif |
29 | |
30 | #if !defined(HAVE_CONFIG_H) |
31 | #if LOCAL_GCC_PREREQ(4,8) || __has_builtin(__builtin_bswap16) |
32 | #define HAVE_BUILTIN_BSWAP16 |
33 | #endif |
34 | #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap32) |
35 | #define HAVE_BUILTIN_BSWAP32 |
36 | #endif |
37 | #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap64) |
38 | #define HAVE_BUILTIN_BSWAP64 |
39 | #endif |
40 | #endif // !HAVE_CONFIG_H |
41 | |
42 | static WEBP_INLINE uint16_t BSwap16(uint16_t x) { |
43 | #if defined(HAVE_BUILTIN_BSWAP16) |
44 | return __builtin_bswap16(x); |
45 | #elif defined(_MSC_VER) |
46 | return _byteswap_ushort(x); |
47 | #else |
48 | // gcc will recognize a 'rorw $8, ...' here: |
49 | return (x >> 8) | ((x & 0xff) << 8); |
50 | #endif // HAVE_BUILTIN_BSWAP16 |
51 | } |
52 | |
53 | static WEBP_INLINE uint32_t BSwap32(uint32_t x) { |
54 | #if defined(WEBP_USE_MIPS32_R2) |
55 | uint32_t ret; |
56 | __asm__ volatile ( |
57 | "wsbh %[ret], %[x] \n\t" |
58 | "rotr %[ret], %[ret], 16 \n\t" |
59 | : [ret]"=r" (ret) |
60 | : [x]"r" (x) |
61 | ); |
62 | return ret; |
63 | #elif defined(HAVE_BUILTIN_BSWAP32) |
64 | return __builtin_bswap32(x); |
65 | #elif defined(__i386__) || defined(__x86_64__) |
66 | uint32_t swapped_bytes; |
67 | __asm__ volatile("bswap %0" : "=r" (swapped_bytes) : "0" (x)); |
68 | return swapped_bytes; |
69 | #elif defined(_MSC_VER) |
70 | return (uint32_t)_byteswap_ulong(x); |
71 | #else |
72 | return (x >> 24) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | (x << 24); |
73 | #endif // HAVE_BUILTIN_BSWAP32 |
74 | } |
75 | |
76 | static WEBP_INLINE uint64_t BSwap64(uint64_t x) { |
77 | #if defined(HAVE_BUILTIN_BSWAP64) |
78 | return __builtin_bswap64(x); |
79 | #elif defined(__x86_64__) |
80 | uint64_t swapped_bytes; |
81 | __asm__ volatile("bswapq %0" : "=r" (swapped_bytes) : "0" (x)); |
82 | return swapped_bytes; |
83 | #elif defined(_MSC_VER) |
84 | return (uint64_t)_byteswap_uint64(x); |
85 | #else // generic code for swapping 64-bit values (suggested by bdb@) |
86 | x = ((x & 0xffffffff00000000ull) >> 32) | ((x & 0x00000000ffffffffull) << 32); |
87 | x = ((x & 0xffff0000ffff0000ull) >> 16) | ((x & 0x0000ffff0000ffffull) << 16); |
88 | x = ((x & 0xff00ff00ff00ff00ull) >> 8) | ((x & 0x00ff00ff00ff00ffull) << 8); |
89 | return x; |
90 | #endif // HAVE_BUILTIN_BSWAP64 |
91 | } |
92 | |
93 | #endif // WEBP_UTILS_ENDIAN_INL_UTILS_H_ |
94 | |