runtime/objc-config.h

   1 /*
   2  * Copyright (c) 1999-2002, 2005-2008 Apple Inc.  All Rights Reserved.
   3  *
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   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,
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  18  * Please see the License for the specific language governing rights and
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  23
  24 #ifndef _OBJC_CONFIG_H_
  25 #define _OBJC_CONFIG_H_
  26
  27 #include <TargetConditionals.h>
  28
  29 // Define SUPPORT_GC=1 to enable garbage collection.
  30 // Be sure to edit OBJC_NO_GC in objc-auto.h as well.
  31 #if TARGET_OS_EMBEDDED  ||  TARGET_OS_IPHONE  ||  TARGET_OS_WIN32
  32 #   define SUPPORT_GC 0
  33 #else
  34 #   define SUPPORT_GC 1
  35 #endif
  36
  37 // Define SUPPORT_ZONES=1 to enable malloc zone support in NXHashTable.
  38 #if TARGET_OS_EMBEDDED  ||  TARGET_OS_IPHONE
  39 #   define SUPPORT_ZONES 0
  40 #else
  41 #   define SUPPORT_ZONES 1
  42 #endif
  43
  44 // Define SUPPORT_MOD=1 to use the mod operator in NXHashTable and objc-sel-set
  45 #if defined(__arm__)
  46 #   define SUPPORT_MOD 0
  47 #else
  48 #   define SUPPORT_MOD 1
  49 #endif
  50
  51 // Define SUPPORT_PREOPT=1 to enable dyld shared cache optimizations
  52 #if TARGET_OS_WIN32  ||  TARGET_IPHONE_SIMULATOR
  53 #   define SUPPORT_PREOPT 0
  54 #else
  55 #   define SUPPORT_PREOPT 1
  56 #endif
  57
  58 // Define SUPPORT_TAGGED_POINTERS=1 to enable tagged pointer objects
  59 // Be sure to edit tagged pointer SPI in objc-internal.h as well.
  60 #if !(__OBJC2__  &&  __LP64__)
  61 #   define SUPPORT_TAGGED_POINTERS 0
  62 #else
  63 #   define SUPPORT_TAGGED_POINTERS 1
  64 #endif
  65
  66 // Define SUPPORT_MSB_TAGGED_POINTERS to use the MSB
  67 // as the tagged pointer marker instead of the LSB.
  68 // Be sure to edit tagged pointer SPI in objc-internal.h as well.
  69 #if !SUPPORT_TAGGED_POINTERS  ||  !TARGET_OS_IPHONE
  70 #   define SUPPORT_MSB_TAGGED_POINTERS 0
  71 #else
  72 #   define SUPPORT_MSB_TAGGED_POINTERS 1
  73 #endif
  74
  75 // Define SUPPORT_NONPOINTER_ISA=1 to enable extra data in the isa field.
  76 #if !__LP64__  ||  TARGET_OS_WIN32  ||  TARGET_IPHONE_SIMULATOR  ||  __x86_64__
  77 #   define SUPPORT_NONPOINTER_ISA 0
  78 #else
  79 #   define SUPPORT_NONPOINTER_ISA 1
  80 #endif
  81
  82 // Define SUPPORT_FIXUP=1 to repair calls sites for fixup dispatch.
  83 // Fixup messaging itself is no longer supported.
  84 // Be sure to edit objc-abi.h as well (objc_msgSend*_fixup)
  85 // Note TARGET_OS_MAC is also set for iOS simulator.
  86 #if !__x86_64__  ||  !TARGET_OS_MAC
  87 #   define SUPPORT_FIXUP 0
  88 #else
  89 #   define SUPPORT_FIXUP 1
  90 #endif
  91
  92 // Define SUPPORT_IGNORED_SELECTOR_CONSTANT to remap GC-ignored selectors.
  93 // Good: fast ignore in objc_msgSend. Bad: disable shared cache optimizations
  94 // Now used only for old-ABI GC.
  95 // This is required for binary compatibility on 32-bit Mac: rdar://13757938
  96 #if __OBJC2__  ||  !SUPPORT_GC
  97 #   define SUPPORT_IGNORED_SELECTOR_CONSTANT 0
  98 #else
  99 #   define SUPPORT_IGNORED_SELECTOR_CONSTANT 1
 100 #   if defined(__i386__)
 101 #       define kIgnore 0xfffeb010
 102 #   else
 103 #       error unknown architecture
 104 #   endif
 105 #endif
 106
 107 // Define SUPPORT_ZEROCOST_EXCEPTIONS to use "zero-cost" exceptions for OBJC2.
 108 // Be sure to edit objc-exception.h as well (objc_add/removeExceptionHandler)
 109 #if !__OBJC2__  ||  defined(__arm__)
 110 #   define SUPPORT_ZEROCOST_EXCEPTIONS 0
 111 #else
 112 #   define SUPPORT_ZEROCOST_EXCEPTIONS 1
 113 #endif
 114
 115 // Define SUPPORT_ALT_HANDLERS if you're using zero-cost exceptions
 116 // but also need to support AppKit's alt-handler scheme
 117 // Be sure to edit objc-exception.h as well (objc_add/removeExceptionHandler)
 118 #if !SUPPORT_ZEROCOST_EXCEPTIONS  ||  TARGET_OS_IPHONE  ||  TARGET_OS_EMBEDDED
 119 #   define SUPPORT_ALT_HANDLERS 0
 120 #else
 121 #   define SUPPORT_ALT_HANDLERS 1
 122 #endif
 123
 124 // Define SUPPORT_RETURN_AUTORELEASE to optimize autoreleased return values
 125 #if !__OBJC2__  ||  TARGET_OS_WIN32
 126 #   define SUPPORT_RETURN_AUTORELEASE 0
 127 #else
 128 #   define SUPPORT_RETURN_AUTORELEASE 1
 129 #endif
 130
 131 // Define SUPPORT_STRET on architectures that need separate struct-return ABI.
 132 #if defined(__arm64__)
 133 #   define SUPPORT_STRET 0
 134 #else
 135 #   define SUPPORT_STRET 1
 136 #endif
 137
 138 // Define SUPPORT_MESSAGE_LOGGING to enable NSObjCMessageLoggingEnabled
 139 #if TARGET_OS_WIN32  ||  TARGET_OS_EMBEDDED
 140 #   define SUPPORT_MESSAGE_LOGGING 0
 141 #else
 142 #   define SUPPORT_MESSAGE_LOGGING 1
 143 #endif
 144
 145 // Define SUPPORT_QOS_HACK to work around deadlocks due to QoS bugs.
 146 #if !__OBJC2__  ||  TARGET_OS_WIN32
 147 #   define SUPPORT_QOS_HACK 0
 148 #else
 149 #   define SUPPORT_QOS_HACK 1
 150 #endif
 151
 152 // OBJC_INSTRUMENTED controls whether message dispatching is dynamically
 153 // monitored.  Monitoring introduces substantial overhead.
 154 // NOTE: To define this condition, do so in the build command, NOT by
 155 // uncommenting the line here.  This is because objc-class.h heeds this
 156 // condition, but objc-class.h can not #include this file (objc-config.h)
 157 // because objc-class.h is public and objc-config.h is not.
 158 //#define OBJC_INSTRUMENTED
 159
 160 #endif