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
   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 2, 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 COPYING.  If not, write to the
  20    Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 /* Yes!  We are AIX!  */
  24 #define DEFAULT_ABI ABI_AIX
  25 #undef  TARGET_AIX
  26 #define TARGET_AIX 1
  27
  28 /* AIX always has a TOC.  */
  29 #define TARGET_NO_TOC 0
  30 #define TARGET_TOC 1
  31 #define FIXED_R2 1
  32
  33 /* AIX allows r13 to be used in 32-bit mode.  */
  34 #define FIXED_R13 0
  35
  36 /* 32-bit and 64-bit AIX stack boundary is 128.  */
  37 #undef  STACK_BOUNDARY
  38 #define STACK_BOUNDARY 128
  39
  40 /* AIX does not support Altivec.  */
  41 #undef  TARGET_ALTIVEC
  42 #define TARGET_ALTIVEC 0
  43 #undef  TARGET_ALTIVEC_ABI
  44 #define TARGET_ALTIVEC_ABI 0
  45
  46 /* The AIX linker will discard static constructors in object files before
  47    collect has a chance to see them, so scan the object files directly.  */
  48 #define COLLECT_EXPORT_LIST
  49
  50 /* Handle #pragma weak and #pragma pack.  */
  51 #define HANDLE_SYSV_PRAGMA 1
  52
  53 /* This is the only version of nm that collect2 can work with.  */
  54 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  55
  56 #define USER_LABEL_PREFIX  ""
  57
  58 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  59 #define RELATIVE_PREFIX_NOT_LINKDIR
  60
  61 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  62 #define LINK_LIBGCC_SPECIAL_1
  63
  64 #define MFWRAP_SPEC " %{static: %{fmudflap|fmudflapth: \
  65  -brename:malloc,__wrap_malloc -brename:__real_malloc,malloc \
  66  -brename:free,__wrap_free -brename:__real_free,free \
  67  -brename:calloc,__wrap_calloc -brename:__real_calloc,calloc \
  68  -brename:realloc,__wrap_realloc -brename:__real_realloc,realloc \
  69  -brename:mmap,__wrap_mmap -brename:__real_mmap,mmap \
  70  -brename:munmap,__wrap_munmap -brename:__real_munmap,munmap \
  71  -brename:alloca,__wrap_alloca -brename:__real_alloca,alloca \
  72 } %{fmudflapth: \
  73  -brename:pthread_create,__wrap_pthread_create \
  74  -brename:__real_pthread_create,pthread_create \
  75  -brename:pthread_join,__wrap_pthread_join \
  76  -brename:__real_pthread_join,pthread_join \
  77  -brename:pthread_exit,__wrap_pthread_exit \
  78  -brename:__real_pthread_exit,pthread_exit \
  79 }} %{fmudflap|fmudflapth: \
  80  -brename:main,__wrap_main -brename:__real_main,main \
  81 }"
  82
  83 #define MFLIB_SPEC " %{fmudflap: -lmudflap \
  84  %{static:%(link_gcc_c_sequence) -lmudflap}} \
  85  %{fmudflapth: -lmudflapth -lpthread \
  86  %{static:%(link_gcc_c_sequence) -lmudflapth}} "
  87
  88 /* Names to predefine in the preprocessor for this target machine.  */
  89 #define TARGET_OS_AIX_CPP_BUILTINS()            \
  90   do                                            \
  91     {                                           \
  92       builtin_define ("_IBMR2");                \
  93       builtin_define ("_POWER");                \
  94       builtin_define ("_AIX");                  \
  95       builtin_define ("_AIX32");                \
  96       builtin_define ("_AIX41");                \
  97       builtin_define ("_LONG_LONG");            \
  98       if (TARGET_LONG_DOUBLE_128)               \
  99         builtin_define ("__LONGDOUBLE128");     \
 100       builtin_assert ("system=unix");           \
 101       builtin_assert ("system=aix");            \
 102     }                                           \
 103   while (0)
 104
 105 /* Define appropriate architecture macros for preprocessor depending on
 106    target switches.  */
 107
 108 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
 109    %{ansi: -D_ANSI_C_SOURCE}"
 110
 111 #undef ASM_DEFAULT_SPEC
 112 #define ASM_DEFAULT_SPEC ""
 113
 114 /* Tell the assembler to assume that all undefined names are external.
 115
 116    Don't do this until the fixed IBM assembler is more generally available.
 117    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
 118    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
 119    longer be needed.  Also, the extern declaration of mcount in
 120    rs6000_xcoff_file_start will no longer be needed.  */
 121
 122 /* #define ASM_SPEC "-u %(asm_cpu)" */
 123
 124 /* Default location of syscalls.exp under AIX */
 125 #ifndef CROSS_COMPILE
 126 #define LINK_SYSCALLS_SPEC "-bI:/lib/syscalls.exp"
 127 #else
 128 #define LINK_SYSCALLS_SPEC ""
 129 #endif
 130
 131 /* Default location of libg.exp under AIX */
 132 #ifndef CROSS_COMPILE
 133 #define LINK_LIBG_SPEC "-bexport:/usr/lib/libg.exp"
 134 #else
 135 #define LINK_LIBG_SPEC ""
 136 #endif
 137
 138 /* Define the options for the binder: Start text at 512, align all segments
 139    to 512 bytes, and warn if there is text relocation.
 140
 141    The -bhalt:4 option supposedly changes the level at which ld will abort,
 142    but it also suppresses warnings about multiply defined symbols and is
 143    used by the AIX cc command.  So we use it here.
 144
 145    -bnodelcsect undoes a poor choice of default relating to multiply-defined
 146    csects.  See AIX documentation for more information about this.
 147
 148    -bM:SRE tells the linker that the output file is Shared REusable.  Note
 149    that to actually build a shared library you will also need to specify an
 150    export list with the -Wl,-bE option.  */
 151
 152 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\
 153 %{static:-bnso %(link_syscalls) } \
 154 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}"
 155
 156 /* Profiled library versions are used by linking with special directories.  */
 157 #define LIB_SPEC "%{pg:-L/lib/profiled -L/usr/lib/profiled}\
 158 %{p:-L/lib/profiled -L/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 159
 160 /* This now supports a natural alignment mode.  */
 161 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 162 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 163   (TARGET_ALIGN_NATURAL ? (COMPUTED) : \
 164   (TYPE_MODE (TREE_CODE (TREE_TYPE (FIELD)) == ARRAY_TYPE \
 165               ? get_inner_array_type (FIELD) \
 166               : TREE_TYPE (FIELD)) == DFmode \
 167    ? MIN ((COMPUTED), 32) : (COMPUTED)))
 168
 169 /* AIX increases natural record alignment to doubleword if the first
 170    field is an FP double while the FP fields remain word aligned.  */
 171 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)                   \
 172   ((TREE_CODE (STRUCT) == RECORD_TYPE                                   \
 173     || TREE_CODE (STRUCT) == UNION_TYPE                                 \
 174     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)                           \
 175    && TARGET_ALIGN_NATURAL == 0                                         \
 176    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)      \
 177    : MAX ((COMPUTED), (SPECIFIED)))
 178
 179 /* The AIX ABI isn't explicit on whether aggregates smaller than a
 180    word/doubleword should be padded upward or downward.  One could
 181    reasonably assume that they follow the normal rules for structure
 182    layout treating the parameter area as any other block of memory,
 183    then map the reg param area to registers, i.e., pad upward, which
 184    is the way IBM Compilers for AIX behave.
 185    Setting both of the following defines results in this behavior.  */
 186 #define AGGREGATE_PADDING_FIXED 1
 187 #define AGGREGATES_PAD_UPWARD_ALWAYS 1
 188
 189 /* Specify padding for the last element of a block move between
 190    registers and memory.  FIRST is nonzero if this is the only
 191    element.  */
 192 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 193   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
 194
 195 /* Indicate that jump tables go in the text section.  */
 196
 197 #define JUMP_TABLES_IN_TEXT_SECTION 1
 198
 199 /* Define any extra SPECS that the compiler needs to generate.  */
 200 #undef  SUBTARGET_EXTRA_SPECS
 201 #define SUBTARGET_EXTRA_SPECS                                           \
 202   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 203   { "link_libg",                LINK_LIBG_SPEC }
 204
 205 /* Define cutoff for using external functions to save floating point.  */
 206 #define FP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) == 62 || (FIRST_REG) == 63)
 207
 208 /* __throw will restore its own return address to be the same as the
 209    return address of the function that the throw is being made to.
 210    This is unfortunate, because we want to check the original
 211    return address to see if we need to restore the TOC.
 212    So we have to squirrel it away with this.  */
 213 #define SETUP_FRAME_ADDRESSES() rs6000_aix_emit_builtin_unwind_init ()
 214
 215 /* If the current unwind info (FS) does not contain explicit info
 216    saving R2, then we have to do a minor amount of code reading to
 217    figure out if it was saved.  The big problem here is that the
 218    code that does the save/restore is generated by the linker, so
 219    we have no good way to determine at compile time what to do.  */
 220
 221 #ifdef __64BIT__
 222 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 223   do {                                                                  \
 224     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 225       {                                                                 \
 226         unsigned int *insn                                              \
 227           = (unsigned int *)                                            \
 228             _Unwind_GetGR ((CTX), LINK_REGISTER_REGNUM);                \
 229         if (*insn == 0xE8410028)                                        \
 230           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 40);                 \
 231       }                                                                 \
 232   } while (0)
 233 #else
 234 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 235   do {                                                                  \
 236     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 237       {                                                                 \
 238         unsigned int *insn                                              \
 239           = (unsigned int *)                                            \
 240             _Unwind_GetGR ((CTX), LINK_REGISTER_REGNUM);                \
 241         if (*insn == 0x80410014)                                        \
 242           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 20);                 \
 243       }                                                                 \
 244   } while (0)
 245 #endif
 246
 247 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)
 248
 249 /* Print subsidiary information on the compiler version in use.  */
 250 #define TARGET_VERSION ;
 251
 252 /* No version of AIX fully supports AltiVec or 64-bit instructions in
 253    32-bit mode.  */
 254 #define OS_MISSING_POWERPC64 1
 255 #define OS_MISSING_ALTIVEC 1
 256
 257 /* WINT_TYPE */
 258 #define WINT_TYPE "int"