ReactOS 0.4.15-dev-5666-gc548b97
compiler.h
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1/*
2 * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under both the BSD-style license (found in the
6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7 * in the COPYING file in the root directory of this source tree).
8 * You may select, at your option, one of the above-listed licenses.
9 */
10
11#ifndef ZSTD_COMPILER_H
12#define ZSTD_COMPILER_H
13
14/*-*******************************************************
15* Compiler specifics
16*********************************************************/
17/* force inlining */
18
19#if !defined(ZSTD_NO_INLINE)
20#if (defined(__GNUC__) && !defined(__STRICT_ANSI__)) || defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
21# define INLINE_KEYWORD inline
22#else
23# define INLINE_KEYWORD
24#endif
25
26#if defined(__GNUC__) || defined(__ICCARM__)
27# define FORCE_INLINE_ATTR __attribute__((always_inline))
28#elif defined(_MSC_VER)
29# define FORCE_INLINE_ATTR __forceinline
30#else
31# define FORCE_INLINE_ATTR
32#endif
33
34#else
35
36#define INLINE_KEYWORD
37#define FORCE_INLINE_ATTR
38
39#endif
40
46#define FORCE_INLINE_TEMPLATE static INLINE_KEYWORD FORCE_INLINE_ATTR
58#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 8 && __GNUC__ < 5
59# define HINT_INLINE static INLINE_KEYWORD
60#else
61# define HINT_INLINE static INLINE_KEYWORD FORCE_INLINE_ATTR
62#endif
63
64/* UNUSED_ATTR tells the compiler it is okay if the function is unused. */
65#if defined(__GNUC__)
66# define UNUSED_ATTR __attribute__((unused))
67#else
68# define UNUSED_ATTR
69#endif
70
71/* force no inlining */
72#ifdef _MSC_VER
73# define FORCE_NOINLINE static __declspec(noinline)
74#else
75# if defined(__GNUC__) || defined(__ICCARM__)
76# define FORCE_NOINLINE static __attribute__((__noinline__))
77# else
78# define FORCE_NOINLINE static
79# endif
80#endif
81
82/* target attribute */
83#ifndef __has_attribute
84 #define __has_attribute(x) 0 /* Compatibility with non-clang compilers. */
85#endif
86#if defined(__GNUC__) || defined(__ICCARM__)
87# define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
88#else
89# define TARGET_ATTRIBUTE(target)
90#endif
91
92/* Enable runtime BMI2 dispatch based on the CPU.
93 * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
94 */
95#ifndef DYNAMIC_BMI2
96 #if ((defined(__clang__) && __has_attribute(__target__)) \
97 || (defined(__GNUC__) \
98 && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
99 && (defined(__x86_64__) || defined(_M_X86)) \
100 && !defined(__BMI2__)
101 # define DYNAMIC_BMI2 1
102 #else
103 # define DYNAMIC_BMI2 0
104 #endif
105#endif
106
107/* prefetch
108 * can be disabled, by declaring NO_PREFETCH build macro */
109#if defined(NO_PREFETCH)
110# define PREFETCH_L1(ptr) (void)(ptr) /* disabled */
111# define PREFETCH_L2(ptr) (void)(ptr) /* disabled */
112#else
113# if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) /* _mm_prefetch() is not defined outside of x86/x64 */
114# include <mmintrin.h> /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
115# define PREFETCH_L1(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
116# define PREFETCH_L2(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T1)
117# elif defined(__aarch64__)
118# define PREFETCH_L1(ptr) __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr)))
119# define PREFETCH_L2(ptr) __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr)))
120# elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
121# define PREFETCH_L1(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */)
122# define PREFETCH_L2(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 2 /* locality */)
123# else
124# define PREFETCH_L1(ptr) (void)(ptr) /* disabled */
125# define PREFETCH_L2(ptr) (void)(ptr) /* disabled */
126# endif
127#endif /* NO_PREFETCH */
128
129#define CACHELINE_SIZE 64
130
131#define PREFETCH_AREA(p, s) { \
132 const char* const _ptr = (const char*)(p); \
133 size_t const _size = (size_t)(s); \
134 size_t _pos; \
135 for (_pos=0; _pos<_size; _pos+=CACHELINE_SIZE) { \
136 PREFETCH_L2(_ptr + _pos); \
137 } \
138}
139
140/* vectorization
141 * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax */
142#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__)
143# if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) || (__GNUC__ >= 5)
144# define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize")))
145# else
146# define DONT_VECTORIZE _Pragma("GCC optimize(\"no-tree-vectorize\")")
147# endif
148#else
149# define DONT_VECTORIZE
150#endif
151
152/* Tell the compiler that a branch is likely or unlikely.
153 * Only use these macros if it causes the compiler to generate better code.
154 * If you can remove a LIKELY/UNLIKELY annotation without speed changes in gcc
155 * and clang, please do.
156 */
157#if defined(__GNUC__)
158#define LIKELY(x) (__builtin_expect((x), 1))
159#define UNLIKELY(x) (__builtin_expect((x), 0))
160#else
161#define LIKELY(x) (x)
162#define UNLIKELY(x) (x)
163#endif
164
165/* disable warnings */
166#ifdef _MSC_VER /* Visual Studio */
167# include <intrin.h> /* For Visual 2005 */
168# pragma warning(disable : 4100) /* disable: C4100: unreferenced formal parameter */
169# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
170# pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */
171# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
172# pragma warning(disable : 4324) /* disable: C4324: padded structure */
173#endif
174
175#endif /* ZSTD_COMPILER_H */