runtime/objc-config.h

   1 /*
   2  * Copyright (c) 1999-2002, 2005-2008 Apple Inc.  All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  18  * Please see the License for the specific language governing rights and
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  22  */
  23
  24 #ifndef _OBJC_CONFIG_H_
  25 #define _OBJC_CONFIG_H_
  26
  27 #include <TargetConditionals.h>
  28
  29 // Avoid the !NDEBUG double negative.
  30 #if !NDEBUG
  31 #   define DEBUG 1
  32 #else
  33 #   define DEBUG 0
  34 #endif
  35
  36 // Define SUPPORT_GC_COMPAT=1 to enable compatibility where GC once was.
  37 // OBJC_NO_GC and OBJC_NO_GC_API in objc-api.h mean something else.
  38 #if !TARGET_OS_OSX
  39 #   define SUPPORT_GC_COMPAT 0
  40 #else
  41 #   define SUPPORT_GC_COMPAT 1
  42 #endif
  43
  44 // Define SUPPORT_ZONES=1 to enable malloc zone support in NXHashTable.
  45 #if !(TARGET_OS_OSX || TARGET_OS_MACCATALYST)
  46 #   define SUPPORT_ZONES 0
  47 #else
  48 #   define SUPPORT_ZONES 1
  49 #endif
  50
  51 // Define SUPPORT_MOD=1 to use the mod operator in NXHashTable and objc-sel-set
  52 #if defined(__arm__)
  53 #   define SUPPORT_MOD 0
  54 #else
  55 #   define SUPPORT_MOD 1
  56 #endif
  57
  58 // Define SUPPORT_PREOPT=1 to enable dyld shared cache optimizations
  59 #if TARGET_OS_WIN32
  60 #   define SUPPORT_PREOPT 0
  61 #else
  62 #   define SUPPORT_PREOPT 1
  63 #endif
  64
  65 // Define SUPPORT_TAGGED_POINTERS=1 to enable tagged pointer objects
  66 // Be sure to edit tagged pointer SPI in objc-internal.h as well.
  67 #if !__LP64__
  68 #   define SUPPORT_TAGGED_POINTERS 0
  69 #else
  70 #   define SUPPORT_TAGGED_POINTERS 1
  71 #endif
  72
  73 // Define SUPPORT_MSB_TAGGED_POINTERS to use the MSB
  74 // as the tagged pointer marker instead of the LSB.
  75 // Be sure to edit tagged pointer SPI in objc-internal.h as well.
  76 #if !SUPPORT_TAGGED_POINTERS  ||  ((TARGET_OS_OSX || TARGET_OS_MACCATALYST) && __x86_64__)
  77 #   define SUPPORT_MSB_TAGGED_POINTERS 0
  78 #else
  79 #   define SUPPORT_MSB_TAGGED_POINTERS 1
  80 #endif
  81
  82 // Define SUPPORT_INDEXED_ISA=1 on platforms that store the class in the isa
  83 // field as an index into a class table.
  84 // Note, keep this in sync with any .s files which also define it.
  85 // Be sure to edit objc-abi.h as well.
  86 #if __ARM_ARCH_7K__ >= 2  ||  (__arm64__ && !__LP64__)
  87 #   define SUPPORT_INDEXED_ISA 1
  88 #else
  89 #   define SUPPORT_INDEXED_ISA 0
  90 #endif
  91
  92 // Define SUPPORT_PACKED_ISA=1 on platforms that store the class in the isa
  93 // field as a maskable pointer with other data around it.
  94 #if (!__LP64__  ||  TARGET_OS_WIN32  ||  \
  95      (TARGET_OS_SIMULATOR && !TARGET_OS_MACCATALYST && !__arm64__))
  96 #   define SUPPORT_PACKED_ISA 0
  97 #else
  98 #   define SUPPORT_PACKED_ISA 1
  99 #endif
 100
 101 // Define SUPPORT_NONPOINTER_ISA=1 on any platform that may store something
 102 // in the isa field that is not a raw pointer.
 103 #if !SUPPORT_INDEXED_ISA  &&  !SUPPORT_PACKED_ISA
 104 #   define SUPPORT_NONPOINTER_ISA 0
 105 #else
 106 #   define SUPPORT_NONPOINTER_ISA 1
 107 #endif
 108
 109 // Define SUPPORT_FIXUP=1 to repair calls sites for fixup dispatch.
 110 // Fixup messaging itself is no longer supported.
 111 // Be sure to edit objc-abi.h as well (objc_msgSend*_fixup)
 112 #if !(defined(__x86_64__) && (TARGET_OS_OSX || TARGET_OS_SIMULATOR))
 113 #   define SUPPORT_FIXUP 0
 114 #else
 115 #   define SUPPORT_FIXUP 1
 116 #endif
 117
 118 // Define SUPPORT_ZEROCOST_EXCEPTIONS to use "zero-cost" exceptions for OBJC2.
 119 // Be sure to edit objc-exception.h as well (objc_add/removeExceptionHandler)
 120 #if defined(__arm__)  &&  __USING_SJLJ_EXCEPTIONS__
 121 #   define SUPPORT_ZEROCOST_EXCEPTIONS 0
 122 #else
 123 #   define SUPPORT_ZEROCOST_EXCEPTIONS 1
 124 #endif
 125
 126 // Define SUPPORT_ALT_HANDLERS if you're using zero-cost exceptions
 127 // but also need to support AppKit's alt-handler scheme
 128 // Be sure to edit objc-exception.h as well (objc_add/removeExceptionHandler)
 129 #if !SUPPORT_ZEROCOST_EXCEPTIONS  ||  !TARGET_OS_OSX
 130 #   define SUPPORT_ALT_HANDLERS 0
 131 #else
 132 #   define SUPPORT_ALT_HANDLERS 1
 133 #endif
 134
 135 // Define SUPPORT_RETURN_AUTORELEASE to optimize autoreleased return values
 136 #if TARGET_OS_WIN32
 137 #   define SUPPORT_RETURN_AUTORELEASE 0
 138 #else
 139 #   define SUPPORT_RETURN_AUTORELEASE 1
 140 #endif
 141
 142 // Define SUPPORT_STRET on architectures that need separate struct-return ABI.
 143 #if defined(__arm64__)
 144 #   define SUPPORT_STRET 0
 145 #else
 146 #   define SUPPORT_STRET 1
 147 #endif
 148
 149 // Define SUPPORT_MESSAGE_LOGGING to enable NSObjCMessageLoggingEnabled
 150 #if !TARGET_OS_OSX
 151 #   define SUPPORT_MESSAGE_LOGGING 0
 152 #else
 153 #   define SUPPORT_MESSAGE_LOGGING 1
 154 #endif
 155
 156 // Define SUPPORT_AUTORELEASEPOOL_DEDDUP_PTRS to combine consecutive pointers to the same object in autorelease pools
 157 #if !__LP64__
 158 #   define SUPPORT_AUTORELEASEPOOL_DEDUP_PTRS 0
 159 #else
 160 #   define SUPPORT_AUTORELEASEPOOL_DEDUP_PTRS 1
 161 #endif
 162
 163 // Define HAVE_TASK_RESTARTABLE_RANGES to enable usage of
 164 // task_restartable_ranges_synchronize()
 165 #if TARGET_OS_SIMULATOR || defined(__i386__) || defined(__arm__) || !TARGET_OS_MAC
 166 #   define HAVE_TASK_RESTARTABLE_RANGES 0
 167 #else
 168 #   define HAVE_TASK_RESTARTABLE_RANGES 1
 169 #endif
 170
 171 // OBJC_INSTRUMENTED controls whether message dispatching is dynamically
 172 // monitored.  Monitoring introduces substantial overhead.
 173 // NOTE: To define this condition, do so in the build command, NOT by
 174 // uncommenting the line here.  This is because objc-class.h heeds this
 175 // condition, but objc-class.h can not #include this file (objc-config.h)
 176 // because objc-class.h is public and objc-config.h is not.
 177 //#define OBJC_INSTRUMENTED
 178
 179 // The runtimeLock is a mutex always held hence the cache lock is
 180 // redundant and can be elided.
 181 //
 182 // If the runtime lock ever becomes a rwlock again,
 183 // the cache lock would need to be used again
 184 #define CONFIG_USE_CACHE_LOCK 0
 185
 186 // Determine how the method cache stores IMPs.
 187 #define CACHE_IMP_ENCODING_NONE 1 // Method cache contains raw IMP.
 188 #define CACHE_IMP_ENCODING_ISA_XOR 2 // Method cache contains ISA ^ IMP.
 189 #define CACHE_IMP_ENCODING_PTRAUTH 3 // Method cache contains ptrauth'd IMP.
 190
 191 #if __PTRAUTH_INTRINSICS__
 192 // Always use ptrauth when it's supported.
 193 #define CACHE_IMP_ENCODING CACHE_IMP_ENCODING_PTRAUTH
 194 #elif defined(__arm__)
 195 // 32-bit ARM uses no encoding.
 196 #define CACHE_IMP_ENCODING CACHE_IMP_ENCODING_NONE
 197 #else
 198 // Everything else uses ISA ^ IMP.
 199 #define CACHE_IMP_ENCODING CACHE_IMP_ENCODING_ISA_XOR
 200 #endif
 201
 202 #define CACHE_MASK_STORAGE_OUTLINED 1
 203 #define CACHE_MASK_STORAGE_HIGH_16 2
 204 #define CACHE_MASK_STORAGE_LOW_4 3
 205 #define CACHE_MASK_STORAGE_HIGH_16_BIG_ADDRS 4
 206
 207 #if defined(__arm64__) && __LP64__
 208 #if TARGET_OS_OSX || TARGET_OS_SIMULATOR
 209 #define CACHE_MASK_STORAGE CACHE_MASK_STORAGE_HIGH_16_BIG_ADDRS
 210 #else
 211 #define CACHE_MASK_STORAGE CACHE_MASK_STORAGE_HIGH_16
 212 #endif
 213 #elif defined(__arm64__) && !__LP64__
 214 #define CACHE_MASK_STORAGE CACHE_MASK_STORAGE_LOW_4
 215 #else
 216 #define CACHE_MASK_STORAGE CACHE_MASK_STORAGE_OUTLINED
 217 #endif
 218
 219 // Constants used for signing/authing isas. This doesn't quite belong
 220 // here, but the asm files can't import other headers.
 221 #define ISA_SIGNING_DISCRIMINATOR 0x6AE1
 222 #define ISA_SIGNING_DISCRIMINATOR_CLASS_SUPERCLASS 0xB5AB
 223
 224 #define ISA_SIGNING_KEY ptrauth_key_process_independent_data
 225
 226 // ISA signing authentication modes. Set ISA_SIGNING_AUTH_MODE to one
 227 // of these to choose how ISAs are authenticated.
 228 #define ISA_SIGNING_STRIP 1 // Strip the signature whenever reading an ISA.
 229 #define ISA_SIGNING_AUTH  2 // Authenticate the signature on all ISAs.
 230
 231
 232 // ISA signing modes. Set ISA_SIGNING_SIGN_MODE to one of these to
 233 // choose how ISAs are signed.
 234 #define ISA_SIGNING_SIGN_NONE       1 // Sign no ISAs.
 235 #define ISA_SIGNING_SIGN_ONLY_SWIFT 2 // Only sign ISAs of Swift objects.
 236 #define ISA_SIGNING_SIGN_ALL        3 // Sign all ISAs.
 237
 238 #if __has_feature(ptrauth_objc_isa_strips) || __has_feature(ptrauth_objc_isa_signs) || __has_feature(ptrauth_objc_isa_authenticates)
 239 #   if __has_feature(ptrauth_objc_isa_authenticates)
 240 #       define ISA_SIGNING_AUTH_MODE ISA_SIGNING_AUTH
 241 #   else
 242 #       define ISA_SIGNING_AUTH_MODE ISA_SIGNING_STRIP
 243 #   endif
 244 #   if __has_feature(ptrauth_objc_isa_signs)
 245 #       define ISA_SIGNING_SIGN_MODE ISA_SIGNING_SIGN_ALL
 246 #   else
 247 #       define ISA_SIGNING_SIGN_MODE ISA_SIGNING_SIGN_NONE
 248 #   endif
 249 #else
 250 #   if __has_feature(ptrauth_objc_isa)
 251 #       define ISA_SIGNING_AUTH_MODE ISA_SIGNING_AUTH
 252 #       define ISA_SIGNING_SIGN_MODE ISA_SIGNING_SIGN_ALL
 253 #   else
 254 #       define ISA_SIGNING_AUTH_MODE ISA_SIGNING_STRIP
 255 #       define ISA_SIGNING_SIGN_MODE ISA_SIGNING_SIGN_NONE
 256 #   endif
 257 #endif
 258
 259 // When set, an unsigned superclass pointer is treated as Nil, which
 260 // will treat the class as if its superclass was weakly linked and
 261 // not loaded, and cause uses of the class to resolve to Nil.
 262 #define SUPERCLASS_SIGNING_TREAT_UNSIGNED_AS_NIL 0
 263
 264 #if defined(__arm64__) && TARGET_OS_IOS && !TARGET_OS_SIMULATOR && !TARGET_OS_MACCATALYST
 265 #define CONFIG_USE_PREOPT_CACHES 1
 266 #else
 267 #define CONFIG_USE_PREOPT_CACHES 0
 268 #endif
 269
 270 // When set to 1, small methods in the shared cache have a direct
 271 // offset to a selector. When set to 0, small methods in the shared
 272 // cache have the same format as other small methods, with an offset
 273 // to a selref.
 274 #define CONFIG_SHARED_CACHE_RELATIVE_DIRECT_SELECTORS 1
 275
 276 #endif