xref: /aosp_15_r20/external/zstd/lib/common/portability_macros.h (revision 01826a4963a0d8a59bc3812d29bdf0fb76416722)
1*01826a49SYabin Cui /*
2*01826a49SYabin Cui  * Copyright (c) Meta Platforms, Inc. and affiliates.
3*01826a49SYabin Cui  * All rights reserved.
4*01826a49SYabin Cui  *
5*01826a49SYabin Cui  * This source code is licensed under both the BSD-style license (found in the
6*01826a49SYabin Cui  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7*01826a49SYabin Cui  * in the COPYING file in the root directory of this source tree).
8*01826a49SYabin Cui  * You may select, at your option, one of the above-listed licenses.
9*01826a49SYabin Cui  */
10*01826a49SYabin Cui 
11*01826a49SYabin Cui #ifndef ZSTD_PORTABILITY_MACROS_H
12*01826a49SYabin Cui #define ZSTD_PORTABILITY_MACROS_H
13*01826a49SYabin Cui 
14*01826a49SYabin Cui /**
15*01826a49SYabin Cui  * This header file contains macro definitions to support portability.
16*01826a49SYabin Cui  * This header is shared between C and ASM code, so it MUST only
17*01826a49SYabin Cui  * contain macro definitions. It MUST not contain any C code.
18*01826a49SYabin Cui  *
19*01826a49SYabin Cui  * This header ONLY defines macros to detect platforms/feature support.
20*01826a49SYabin Cui  *
21*01826a49SYabin Cui  */
22*01826a49SYabin Cui 
23*01826a49SYabin Cui 
24*01826a49SYabin Cui /* compat. with non-clang compilers */
25*01826a49SYabin Cui #ifndef __has_attribute
26*01826a49SYabin Cui   #define __has_attribute(x) 0
27*01826a49SYabin Cui #endif
28*01826a49SYabin Cui 
29*01826a49SYabin Cui /* compat. with non-clang compilers */
30*01826a49SYabin Cui #ifndef __has_builtin
31*01826a49SYabin Cui #  define __has_builtin(x) 0
32*01826a49SYabin Cui #endif
33*01826a49SYabin Cui 
34*01826a49SYabin Cui /* compat. with non-clang compilers */
35*01826a49SYabin Cui #ifndef __has_feature
36*01826a49SYabin Cui #  define __has_feature(x) 0
37*01826a49SYabin Cui #endif
38*01826a49SYabin Cui 
39*01826a49SYabin Cui /* detects whether we are being compiled under msan */
40*01826a49SYabin Cui #ifndef ZSTD_MEMORY_SANITIZER
41*01826a49SYabin Cui #  if __has_feature(memory_sanitizer)
42*01826a49SYabin Cui #    define ZSTD_MEMORY_SANITIZER 1
43*01826a49SYabin Cui #  else
44*01826a49SYabin Cui #    define ZSTD_MEMORY_SANITIZER 0
45*01826a49SYabin Cui #  endif
46*01826a49SYabin Cui #endif
47*01826a49SYabin Cui 
48*01826a49SYabin Cui /* detects whether we are being compiled under asan */
49*01826a49SYabin Cui #ifndef ZSTD_ADDRESS_SANITIZER
50*01826a49SYabin Cui #  if __has_feature(address_sanitizer)
51*01826a49SYabin Cui #    define ZSTD_ADDRESS_SANITIZER 1
52*01826a49SYabin Cui #  elif defined(__SANITIZE_ADDRESS__)
53*01826a49SYabin Cui #    define ZSTD_ADDRESS_SANITIZER 1
54*01826a49SYabin Cui #  else
55*01826a49SYabin Cui #    define ZSTD_ADDRESS_SANITIZER 0
56*01826a49SYabin Cui #  endif
57*01826a49SYabin Cui #endif
58*01826a49SYabin Cui 
59*01826a49SYabin Cui /* detects whether we are being compiled under dfsan */
60*01826a49SYabin Cui #ifndef ZSTD_DATAFLOW_SANITIZER
61*01826a49SYabin Cui # if __has_feature(dataflow_sanitizer)
62*01826a49SYabin Cui #  define ZSTD_DATAFLOW_SANITIZER 1
63*01826a49SYabin Cui # else
64*01826a49SYabin Cui #  define ZSTD_DATAFLOW_SANITIZER 0
65*01826a49SYabin Cui # endif
66*01826a49SYabin Cui #endif
67*01826a49SYabin Cui 
68*01826a49SYabin Cui /* Mark the internal assembly functions as hidden  */
69*01826a49SYabin Cui #ifdef __ELF__
70*01826a49SYabin Cui # define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func
71*01826a49SYabin Cui #elif defined(__APPLE__)
72*01826a49SYabin Cui # define ZSTD_HIDE_ASM_FUNCTION(func) .private_extern func
73*01826a49SYabin Cui #else
74*01826a49SYabin Cui # define ZSTD_HIDE_ASM_FUNCTION(func)
75*01826a49SYabin Cui #endif
76*01826a49SYabin Cui 
77*01826a49SYabin Cui /* Enable runtime BMI2 dispatch based on the CPU.
78*01826a49SYabin Cui  * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
79*01826a49SYabin Cui  */
80*01826a49SYabin Cui #ifndef DYNAMIC_BMI2
81*01826a49SYabin Cui   #if ((defined(__clang__) && __has_attribute(__target__)) \
82*01826a49SYabin Cui       || (defined(__GNUC__) \
83*01826a49SYabin Cui           && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
84*01826a49SYabin Cui       && (defined(__x86_64__) || defined(_M_X64)) \
85*01826a49SYabin Cui       && !defined(__BMI2__)
86*01826a49SYabin Cui   #  define DYNAMIC_BMI2 1
87*01826a49SYabin Cui   #else
88*01826a49SYabin Cui   #  define DYNAMIC_BMI2 0
89*01826a49SYabin Cui   #endif
90*01826a49SYabin Cui #endif
91*01826a49SYabin Cui 
92*01826a49SYabin Cui /**
93*01826a49SYabin Cui  * Only enable assembly for GNUC compatible compilers,
94*01826a49SYabin Cui  * because other platforms may not support GAS assembly syntax.
95*01826a49SYabin Cui  *
96*01826a49SYabin Cui  * Only enable assembly for Linux / MacOS, other platforms may
97*01826a49SYabin Cui  * work, but they haven't been tested. This could likely be
98*01826a49SYabin Cui  * extended to BSD systems.
99*01826a49SYabin Cui  *
100*01826a49SYabin Cui  * Disable assembly when MSAN is enabled, because MSAN requires
101*01826a49SYabin Cui  * 100% of code to be instrumented to work.
102*01826a49SYabin Cui  */
103*01826a49SYabin Cui #if defined(__GNUC__)
104*01826a49SYabin Cui #  if defined(__linux__) || defined(__linux) || defined(__APPLE__)
105*01826a49SYabin Cui #    if ZSTD_MEMORY_SANITIZER
106*01826a49SYabin Cui #      define ZSTD_ASM_SUPPORTED 0
107*01826a49SYabin Cui #    elif ZSTD_DATAFLOW_SANITIZER
108*01826a49SYabin Cui #      define ZSTD_ASM_SUPPORTED 0
109*01826a49SYabin Cui #    else
110*01826a49SYabin Cui #      define ZSTD_ASM_SUPPORTED 1
111*01826a49SYabin Cui #    endif
112*01826a49SYabin Cui #  else
113*01826a49SYabin Cui #    define ZSTD_ASM_SUPPORTED 0
114*01826a49SYabin Cui #  endif
115*01826a49SYabin Cui #else
116*01826a49SYabin Cui #  define ZSTD_ASM_SUPPORTED 0
117*01826a49SYabin Cui #endif
118*01826a49SYabin Cui 
119*01826a49SYabin Cui /**
120*01826a49SYabin Cui  * Determines whether we should enable assembly for x86-64
121*01826a49SYabin Cui  * with BMI2.
122*01826a49SYabin Cui  *
123*01826a49SYabin Cui  * Enable if all of the following conditions hold:
124*01826a49SYabin Cui  * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM
125*01826a49SYabin Cui  * - Assembly is supported
126*01826a49SYabin Cui  * - We are compiling for x86-64 and either:
127*01826a49SYabin Cui  *   - DYNAMIC_BMI2 is enabled
128*01826a49SYabin Cui  *   - BMI2 is supported at compile time
129*01826a49SYabin Cui  */
130*01826a49SYabin Cui #if !defined(ZSTD_DISABLE_ASM) &&                                 \
131*01826a49SYabin Cui     ZSTD_ASM_SUPPORTED &&                                         \
132*01826a49SYabin Cui     defined(__x86_64__) &&                                        \
133*01826a49SYabin Cui     (DYNAMIC_BMI2 || defined(__BMI2__))
134*01826a49SYabin Cui # define ZSTD_ENABLE_ASM_X86_64_BMI2 1
135*01826a49SYabin Cui #else
136*01826a49SYabin Cui # define ZSTD_ENABLE_ASM_X86_64_BMI2 0
137*01826a49SYabin Cui #endif
138*01826a49SYabin Cui 
139*01826a49SYabin Cui /*
140*01826a49SYabin Cui  * For x86 ELF targets, add .note.gnu.property section for Intel CET in
141*01826a49SYabin Cui  * assembly sources when CET is enabled.
142*01826a49SYabin Cui  *
143*01826a49SYabin Cui  * Additionally, any function that may be called indirectly must begin
144*01826a49SYabin Cui  * with ZSTD_CET_ENDBRANCH.
145*01826a49SYabin Cui  */
146*01826a49SYabin Cui #if defined(__ELF__) && (defined(__x86_64__) || defined(__i386__)) \
147*01826a49SYabin Cui     && defined(__has_include)
148*01826a49SYabin Cui # if __has_include(<cet.h>)
149*01826a49SYabin Cui #  include <cet.h>
150*01826a49SYabin Cui #  define ZSTD_CET_ENDBRANCH _CET_ENDBR
151*01826a49SYabin Cui # endif
152*01826a49SYabin Cui #endif
153*01826a49SYabin Cui 
154*01826a49SYabin Cui #ifndef ZSTD_CET_ENDBRANCH
155*01826a49SYabin Cui # define ZSTD_CET_ENDBRANCH
156*01826a49SYabin Cui #endif
157*01826a49SYabin Cui 
158*01826a49SYabin Cui #endif /* ZSTD_PORTABILITY_MACROS_H */
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