gcc/config/rs6000/aix.h

   1 /* Definitions of target machine for GNU compiler,
   2    for IBM RS/6000 POWER running AIX.
   3    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GCC.
   7
   8    GCC is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published
  10    by the Free Software Foundation; either version 3, or (at your
  11    option) any later version.
  12
  13    GCC is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GCC; see the file COPYING3.  If not see
  20    <http://www.gnu.org/licenses/>.  */
  21
  22 /* Yes!  We are AIX!  */
  23 #define DEFAULT_ABI ABI_AIX
  24 #undef  TARGET_AIX
  25 #define TARGET_AIX 1
  26
  27 /* AIX always has a TOC.  */
  28 #define TARGET_NO_TOC 0
  29 #define TARGET_TOC 1
  30 #define FIXED_R2 1
  31
  32 /* AIX allows r13 to be used in 32-bit mode.  */
  33 #define FIXED_R13 0
  34
  35 /* 32-bit and 64-bit AIX stack boundary is 128.  */
  36 #undef  STACK_BOUNDARY
  37 #define STACK_BOUNDARY 128
  38
  39 /* AIX does not support Altivec.  */
  40 #undef  TARGET_ALTIVEC
  41 #define TARGET_ALTIVEC 0
  42 #undef  TARGET_ALTIVEC_ABI
  43 #define TARGET_ALTIVEC_ABI 0
  44 #undef  TARGET_IEEEQUAD
  45 #define TARGET_IEEEQUAD 0
  46
  47 /* The AIX linker will discard static constructors in object files before
  48    collect has a chance to see them, so scan the object files directly.  */
  49 #define COLLECT_EXPORT_LIST
  50
  51 /* Handle #pragma weak and #pragma pack.  */
  52 #define HANDLE_SYSV_PRAGMA 1
  53
  54 /* This is the only version of nm that collect2 can work with.  */
  55 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  56
  57 #define USER_LABEL_PREFIX  ""
  58
  59 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  60 #define RELATIVE_PREFIX_NOT_LINKDIR
  61
  62 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  63 #define LINK_LIBGCC_SPECIAL_1
  64
  65 #define MFWRAP_SPEC " %{static: %{fmudflap|fmudflapth: \
  66  -brename:malloc,__wrap_malloc -brename:__real_malloc,malloc \
  67  -brename:free,__wrap_free -brename:__real_free,free \
  68  -brename:calloc,__wrap_calloc -brename:__real_calloc,calloc \
  69  -brename:realloc,__wrap_realloc -brename:__real_realloc,realloc \
  70  -brename:mmap,__wrap_mmap -brename:__real_mmap,mmap \
  71  -brename:munmap,__wrap_munmap -brename:__real_munmap,munmap \
  72  -brename:alloca,__wrap_alloca -brename:__real_alloca,alloca \
  73 } %{fmudflapth: \
  74  -brename:pthread_create,__wrap_pthread_create \
  75  -brename:__real_pthread_create,pthread_create \
  76  -brename:pthread_join,__wrap_pthread_join \
  77  -brename:__real_pthread_join,pthread_join \
  78  -brename:pthread_exit,__wrap_pthread_exit \
  79  -brename:__real_pthread_exit,pthread_exit \
  80 }} %{fmudflap|fmudflapth: \
  81  -brename:main,__wrap_main -brename:__real_main,main \
  82 }"
  83
  84 #define MFLIB_SPEC " %{fmudflap: -lmudflap \
  85  %{static:%(link_gcc_c_sequence) -lmudflap}} \
  86  %{fmudflapth: -lmudflapth -lpthread \
  87  %{static:%(link_gcc_c_sequence) -lmudflapth}} "
  88
  89 /* Names to predefine in the preprocessor for this target machine.  */
  90 #define TARGET_OS_AIX_CPP_BUILTINS()            \
  91   do                                            \
  92     {                                           \
  93       builtin_define ("_IBMR2");                \
  94       builtin_define ("_POWER");                \
  95       builtin_define ("_AIX");                  \
  96       builtin_define ("_AIX32");                \
  97       builtin_define ("_AIX41");                \
  98       builtin_define ("_LONG_LONG");            \
  99       if (TARGET_LONG_DOUBLE_128)               \
 100         builtin_define ("__LONGDOUBLE128");     \
 101       builtin_assert ("system=unix");           \
 102       builtin_assert ("system=aix");            \
 103     }                                           \
 104   while (0)
 105
 106 /* Define appropriate architecture macros for preprocessor depending on
 107    target switches.  */
 108
 109 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
 110    %{ansi: -D_ANSI_C_SOURCE}"
 111
 112 #undef ASM_DEFAULT_SPEC
 113 #define ASM_DEFAULT_SPEC ""
 114
 115 /* Tell the assembler to assume that all undefined names are external.
 116
 117    Don't do this until the fixed IBM assembler is more generally available.
 118    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
 119    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
 120    longer be needed.  Also, the extern declaration of mcount in
 121    rs6000_xcoff_file_start will no longer be needed.  */
 122
 123 /* #define ASM_SPEC "-u %(asm_cpu)" */
 124
 125 /* Default location of syscalls.exp under AIX */
 126 #ifndef CROSS_DIRECTORY_STRUCTURE
 127 #define LINK_SYSCALLS_SPEC "-bI:/lib/syscalls.exp"
 128 #else
 129 #define LINK_SYSCALLS_SPEC ""
 130 #endif
 131
 132 /* Default location of libg.exp under AIX */
 133 #ifndef CROSS_DIRECTORY_STRUCTURE
 134 #define LINK_LIBG_SPEC "-bexport:/usr/lib/libg.exp"
 135 #else
 136 #define LINK_LIBG_SPEC ""
 137 #endif
 138
 139 /* Define the options for the binder: Start text at 512, align all segments
 140    to 512 bytes, and warn if there is text relocation.
 141
 142    The -bhalt:4 option supposedly changes the level at which ld will abort,
 143    but it also suppresses warnings about multiply defined symbols and is
 144    used by the AIX cc command.  So we use it here.
 145
 146    -bnodelcsect undoes a poor choice of default relating to multiply-defined
 147    csects.  See AIX documentation for more information about this.
 148
 149    -bM:SRE tells the linker that the output file is Shared REusable.  Note
 150    that to actually build a shared library you will also need to specify an
 151    export list with the -Wl,-bE option.  */
 152
 153 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\
 154 %{static:-bnso %(link_syscalls) } \
 155 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}"
 156
 157 /* Profiled library versions are used by linking with special directories.  */
 158 #define LIB_SPEC "%{pg:-L/lib/profiled -L/usr/lib/profiled}\
 159 %{p:-L/lib/profiled -L/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 160
 161 /* This now supports a natural alignment mode.  */
 162 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 163 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 164   (TARGET_ALIGN_NATURAL ? (COMPUTED) : \
 165   (TYPE_MODE (TREE_CODE (TREE_TYPE (FIELD)) == ARRAY_TYPE \
 166               ? get_inner_array_type (FIELD) \
 167               : TREE_TYPE (FIELD)) == DFmode \
 168    ? MIN ((COMPUTED), 32) : (COMPUTED)))
 169
 170 /* AIX increases natural record alignment to doubleword if the first
 171    field is an FP double while the FP fields remain word aligned.  */
 172 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)                   \
 173   ((TREE_CODE (STRUCT) == RECORD_TYPE                                   \
 174     || TREE_CODE (STRUCT) == UNION_TYPE                                 \
 175     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)                           \
 176    && TARGET_ALIGN_NATURAL == 0                                         \
 177    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)      \
 178    : MAX ((COMPUTED), (SPECIFIED)))
 179
 180 /* The AIX ABI isn't explicit on whether aggregates smaller than a
 181    word/doubleword should be padded upward or downward.  One could
 182    reasonably assume that they follow the normal rules for structure
 183    layout treating the parameter area as any other block of memory,
 184    then map the reg param area to registers, i.e., pad upward, which
 185    is the way IBM Compilers for AIX behave.
 186    Setting both of the following defines results in this behavior.  */
 187 #define AGGREGATE_PADDING_FIXED 1
 188 #define AGGREGATES_PAD_UPWARD_ALWAYS 1
 189
 190 /* Specify padding for the last element of a block move between
 191    registers and memory.  FIRST is nonzero if this is the only
 192    element.  */
 193 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 194   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
 195
 196 /* Indicate that jump tables go in the text section.  */
 197
 198 #define JUMP_TABLES_IN_TEXT_SECTION 1
 199
 200 /* Define any extra SPECS that the compiler needs to generate.  */
 201 #undef  SUBTARGET_EXTRA_SPECS
 202 #define SUBTARGET_EXTRA_SPECS                                           \
 203   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 204   { "link_libg",                LINK_LIBG_SPEC }
 205
 206 /* Define cutoff for using external functions to save floating point.  */
 207 #define FP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) == 62 || (FIRST_REG) == 63)
 208
 209 /* __throw will restore its own return address to be the same as the
 210    return address of the function that the throw is being made to.
 211    This is unfortunate, because we want to check the original
 212    return address to see if we need to restore the TOC.
 213    So we have to squirrel it away with this.  */
 214 #define SETUP_FRAME_ADDRESSES() rs6000_aix_emit_builtin_unwind_init ()
 215
 216 /* If the current unwind info (FS) does not contain explicit info
 217    saving R2, then we have to do a minor amount of code reading to
 218    figure out if it was saved.  The big problem here is that the
 219    code that does the save/restore is generated by the linker, so
 220    we have no good way to determine at compile time what to do.  */
 221
 222 #define R_LR 65
 223
 224 #ifdef __64BIT__
 225 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 226   do {                                                                  \
 227     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 228       {                                                                 \
 229         unsigned int *insn                                              \
 230           = (unsigned int *)                                            \
 231             _Unwind_GetGR ((CTX), R_LR);                                \
 232         if (*insn == 0xE8410028)                                        \
 233           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 40);                 \
 234       }                                                                 \
 235   } while (0)
 236 #else
 237 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 238   do {                                                                  \
 239     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 240       {                                                                 \
 241         unsigned int *insn                                              \
 242           = (unsigned int *)                                            \
 243             _Unwind_GetGR ((CTX), R_LR);                                \
 244         if (*insn == 0x80410014)                                        \
 245           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 20);                 \
 246       }                                                                 \
 247   } while (0)
 248 #endif
 249
 250 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)
 251
 252 /* Print subsidiary information on the compiler version in use.  */
 253 #define TARGET_VERSION ;
 254
 255 /* No version of AIX fully supports AltiVec or 64-bit instructions in
 256    32-bit mode.  */
 257 #define OS_MISSING_POWERPC64 1
 258 #define OS_MISSING_ALTIVEC 1
 259
 260 /* WINT_TYPE */
 261 #define WINT_TYPE "int"