runtime/isa.h

   1 /*
   2  * @APPLE_LICENSE_HEADER_START@
   3  *
   4  * Copyright (c) 2018 Apple Inc.  All Rights Reserved.
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
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   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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  22  */
  23 /********************************************************************
  24  *
  25  *  isa.h - Definitions of isa fields for C and assembly code.
  26  *
  27  ********************************************************************/
  28
  29 #ifndef _OBJC_ISA_H_
  30 #define _OBJC_ISA_H_
  31
  32 #include "objc-config.h"
  33
  34
  35 #if (!SUPPORT_NONPOINTER_ISA && !SUPPORT_PACKED_ISA && !SUPPORT_INDEXED_ISA) ||\
  36     ( SUPPORT_NONPOINTER_ISA &&  SUPPORT_PACKED_ISA && !SUPPORT_INDEXED_ISA) ||\
  37     ( SUPPORT_NONPOINTER_ISA && !SUPPORT_PACKED_ISA &&  SUPPORT_INDEXED_ISA)
  38     // good config
  39 #else
  40 #   error bad config
  41 #endif
  42
  43
  44 #if SUPPORT_PACKED_ISA
  45
  46     // extra_rc must be the MSB-most field (so it matches carry/overflow flags)
  47     // nonpointer must be the LSB (fixme or get rid of it)
  48     // shiftcls must occupy the same bits that a real class pointer would
  49     // bits + RC_ONE is equivalent to extra_rc + 1
  50     // RC_HALF is the high bit of extra_rc (i.e. half of its range)
  51
  52     // future expansion:
  53     // uintptr_t fast_rr : 1;     // no r/r overrides
  54     // uintptr_t lock : 2;        // lock for atomic property, @synch
  55     // uintptr_t extraBytes : 1;  // allocated with extra bytes
  56
  57 # if __arm64__
  58 // ARM64 simulators have a larger address space, so use the ARM64e
  59 // scheme even when simulators build for ARM64-not-e.
  60 #   if __has_feature(ptrauth_calls) || TARGET_OS_SIMULATOR
  61 #     define ISA_MASK        0x007ffffffffffff8ULL
  62 #     define ISA_MAGIC_MASK  0x0000000000000001ULL
  63 #     define ISA_MAGIC_VALUE 0x0000000000000001ULL
  64 #     define ISA_HAS_CXX_DTOR_BIT 0
  65 #     define ISA_BITFIELD                                                      \
  66         uintptr_t nonpointer        : 1;                                       \
  67         uintptr_t has_assoc         : 1;                                       \
  68         uintptr_t weakly_referenced : 1;                                       \
  69         uintptr_t shiftcls_and_sig  : 52;                                      \
  70         uintptr_t has_sidetable_rc  : 1;                                       \
  71         uintptr_t extra_rc          : 8
  72 #     define RC_ONE   (1ULL<<56)
  73 #     define RC_HALF  (1ULL<<7)
  74 #   else
  75 #     define ISA_MASK        0x0000000ffffffff8ULL
  76 #     define ISA_MAGIC_MASK  0x000003f000000001ULL
  77 #     define ISA_MAGIC_VALUE 0x000001a000000001ULL
  78 #     define ISA_HAS_CXX_DTOR_BIT 1
  79 #     define ISA_BITFIELD                                                      \
  80         uintptr_t nonpointer        : 1;                                       \
  81         uintptr_t has_assoc         : 1;                                       \
  82         uintptr_t has_cxx_dtor      : 1;                                       \
  83         uintptr_t shiftcls          : 33; /*MACH_VM_MAX_ADDRESS 0x1000000000*/ \
  84         uintptr_t magic             : 6;                                       \
  85         uintptr_t weakly_referenced : 1;                                       \
  86         uintptr_t unused            : 1;                                       \
  87         uintptr_t has_sidetable_rc  : 1;                                       \
  88         uintptr_t extra_rc          : 19
  89 #     define RC_ONE   (1ULL<<45)
  90 #     define RC_HALF  (1ULL<<18)
  91 #   endif
  92
  93 # elif __x86_64__
  94 #   define ISA_MASK        0x00007ffffffffff8ULL
  95 #   define ISA_MAGIC_MASK  0x001f800000000001ULL
  96 #   define ISA_MAGIC_VALUE 0x001d800000000001ULL
  97 #   define ISA_HAS_CXX_DTOR_BIT 1
  98 #   define ISA_BITFIELD                                                        \
  99       uintptr_t nonpointer        : 1;                                         \
 100       uintptr_t has_assoc         : 1;                                         \
 101       uintptr_t has_cxx_dtor      : 1;                                         \
 102       uintptr_t shiftcls          : 44; /*MACH_VM_MAX_ADDRESS 0x7fffffe00000*/ \
 103       uintptr_t magic             : 6;                                         \
 104       uintptr_t weakly_referenced : 1;                                         \
 105       uintptr_t unused            : 1;                                         \
 106       uintptr_t has_sidetable_rc  : 1;                                         \
 107       uintptr_t extra_rc          : 8
 108 #   define RC_ONE   (1ULL<<56)
 109 #   define RC_HALF  (1ULL<<7)
 110
 111 # else
 112 #   error unknown architecture for packed isa
 113 # endif
 114
 115 // SUPPORT_PACKED_ISA
 116 #endif
 117
 118
 119 #if SUPPORT_INDEXED_ISA
 120
 121 # if  __ARM_ARCH_7K__ >= 2  ||  (__arm64__ && !__LP64__)
 122     // armv7k or arm64_32
 123
 124 #   define ISA_INDEX_IS_NPI_BIT  0
 125 #   define ISA_INDEX_IS_NPI_MASK 0x00000001
 126 #   define ISA_INDEX_MASK        0x0001FFFC
 127 #   define ISA_INDEX_SHIFT       2
 128 #   define ISA_INDEX_BITS        15
 129 #   define ISA_INDEX_COUNT       (1 << ISA_INDEX_BITS)
 130 #   define ISA_INDEX_MAGIC_MASK  0x001E0001
 131 #   define ISA_INDEX_MAGIC_VALUE 0x001C0001
 132 #   define ISA_HAS_CXX_DTOR_BIT  1
 133 #   define ISA_BITFIELD                         \
 134       uintptr_t nonpointer        : 1;          \
 135       uintptr_t has_assoc         : 1;          \
 136       uintptr_t indexcls          : 15;         \
 137       uintptr_t magic             : 4;          \
 138       uintptr_t has_cxx_dtor      : 1;          \
 139       uintptr_t weakly_referenced : 1;          \
 140       uintptr_t unused            : 1;          \
 141       uintptr_t has_sidetable_rc  : 1;          \
 142       uintptr_t extra_rc          : 7
 143 #   define RC_ONE   (1ULL<<25)
 144 #   define RC_HALF  (1ULL<<6)
 145
 146 # else
 147 #   error unknown architecture for indexed isa
 148 # endif
 149
 150 // SUPPORT_INDEXED_ISA
 151 #endif
 152
 153
 154 // _OBJC_ISA_H_
 155 #endif