1 /* 1
2 * Copyright (c) Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under both the
6 * LICENSE file in the root directory of this
7 * in the COPYING file in the root directory o
8 * You may select, at your option, one of the
9 */
10
11 #ifndef ZSTD_COMPILER_H
12 #define ZSTD_COMPILER_H
13
14 #include "portability_macros.h"
15
16 /*-*******************************************
17 * Compiler specifics
18 **********************************************
19 /* force inlining */
20
21 #if !defined(ZSTD_NO_INLINE)
22 #if (defined(__GNUC__) && !defined(__STRICT_AN
23 # define INLINE_KEYWORD inline
24 #else
25 # define INLINE_KEYWORD
26 #endif
27
28 #define FORCE_INLINE_ATTR __attribute__((alway
29
30 #else
31
32 #define INLINE_KEYWORD
33 #define FORCE_INLINE_ATTR
34
35 #endif
36
37 /*
38 On MSVC qsort requires that functions passed
39 This explicitly marks such functions as __cd
40 if a CC other than __cdecl has been made the
41 */
42 #define WIN_CDECL
43
44 /*
45 * FORCE_INLINE_TEMPLATE is used to define C "
46 * parameters. They must be inlined for the co
47 * branches.
48 */
49 #define FORCE_INLINE_TEMPLATE static INLINE_KE
50 /*
51 * HINT_INLINE is used to help the compiler ge
52 * used for "templates", so it can be tweaked
53 * performance.
54 *
55 * gcc-4.8 and gcc-4.9 have been shown to bene
56 * always_inline attribute.
57 *
58 * clang up to 5.0.0 (trunk) benefit tremendou
59 * attribute.
60 */
61 #if !defined(__clang__) && defined(__GNUC__) &
62 # define HINT_INLINE static INLINE_KEYWORD
63 #else
64 # define HINT_INLINE static INLINE_KEYWORD FO
65 #endif
66
67 /* UNUSED_ATTR tells the compiler it is okay i
68 #define UNUSED_ATTR __attribute__((unused))
69
70 /* force no inlining */
71 #define FORCE_NOINLINE static __attribute__((_
72
73
74 /* target attribute */
75 #define TARGET_ATTRIBUTE(target) __attribute__
76
77 /* Target attribute for BMI2 dynamic dispatch.
78 * Enable lzcnt, bmi, and bmi2.
79 * We test for bmi1 & bmi2. lzcnt is included
80 */
81 #define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE
82
83 /* prefetch
84 * can be disabled, by declaring NO_PREFETCH b
85 #if ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) &&
86 # define PREFETCH_L1(ptr) __builtin_prefetch
87 # define PREFETCH_L2(ptr) __builtin_prefetch
88 #elif defined(__aarch64__)
89 # define PREFETCH_L1(ptr) __asm__ __volatile
90 # define PREFETCH_L2(ptr) __asm__ __volatile
91 #else
92 # define PREFETCH_L1(ptr) (void)(ptr) /* dis
93 # define PREFETCH_L2(ptr) (void)(ptr) /* dis
94 #endif /* NO_PREFETCH */
95
96 #define CACHELINE_SIZE 64
97
98 #define PREFETCH_AREA(p, s) { \
99 const char* const _ptr = (const char*)(p);
100 size_t const _size = (size_t)(s); \
101 size_t _pos; \
102 for (_pos=0; _pos<_size; _pos+=CACHELINE_S
103 PREFETCH_L2(_ptr + _pos); \
104 } \
105 }
106
107 /* vectorization
108 * older GCC (pre gcc-4.3 picked as the cutoff
109 * and some compilers, like Intel ICC and MCST
110 #if !defined(__INTEL_COMPILER) && !defined(__c
111 # if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) ||
112 # define DONT_VECTORIZE __attribute__((opti
113 # else
114 # define DONT_VECTORIZE _Pragma("GCC optimi
115 # endif
116 #else
117 # define DONT_VECTORIZE
118 #endif
119
120 /* Tell the compiler that a branch is likely o
121 * Only use these macros if it causes the comp
122 * If you can remove a LIKELY/UNLIKELY annotat
123 * and clang, please do.
124 */
125 #define LIKELY(x) (__builtin_expect((x), 1))
126 #define UNLIKELY(x) (__builtin_expect((x), 0))
127
128 #if __has_builtin(__builtin_unreachable) || (d
129 # define ZSTD_UNREACHABLE { assert(0), __buil
130 #else
131 # define ZSTD_UNREACHABLE { assert(0); }
132 #endif
133
134 /* disable warnings */
135
136 /*Like DYNAMIC_BMI2 but for compile time deter
137
138
139 /* compile time determination of SIMD support
140
141 /* C-language Attributes are added in C23. */
142 #if defined(__STDC_VERSION__) && (__STDC_VERSI
143 # define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attri
144 #else
145 # define ZSTD_HAS_C_ATTRIBUTE(x) 0
146 #endif
147
148 /* Only use C++ attributes in C++. Some compil
149 * attributes when compiling with C.
150 */
151 #define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
152
153 /* Define ZSTD_FALLTHROUGH macro for annotatin
154 * - C23: https://en.cppreference.com/w/c/lang
155 * - CPP17: https://en.cppreference.com/w/cpp/
156 * - Else: __attribute__((__fallthrough__))
157 */
158 #define ZSTD_FALLTHROUGH fallthrough
159
160 /*-*******************************************
161 * Alignment check
162 **********************************************
163
164 /* this test was initially positioned in mem.h
165 * but this file is removed (or replaced) for
166 * so it's now hosted in compiler.h,
167 * which remains valid for both user & kernel
168 */
169
170 #ifndef ZSTD_ALIGNOF
171 /* covers gcc, clang & MSVC */
172 /* note : this section must come first, before
173 * due to a limitation in the kernel source ge
174 # define ZSTD_ALIGNOF(T) __alignof(T)
175
176 #endif /* ZSTD_ALIGNOF */
177
178 /*-*******************************************
179 * Sanitizer
180 **********************************************
181
182
183
184 #endif /* ZSTD_COMPILER_H */
185
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.