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, 59 Temple Place - Suite 330, Boston,
  21    MA 02111-1307, 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 /* AIX does not support Altivec.  */
  37 #undef  TARGET_ALTIVEC
  38 #define TARGET_ALTIVEC 0
  39 #undef  TARGET_ALTIVEC_ABI
  40 #define TARGET_ALTIVEC_ABI 0
  41 #undef  TARGET_ALTIVEC_VRSAVE
  42 #define TARGET_ALTIVEC_VRSAVE 0
  43
  44 /* The AIX linker will discard static constructors in object files before
  45    collect has a chance to see them, so scan the object files directly.  */
  46 #define COLLECT_EXPORT_LIST
  47
  48 /* Handle #pragma weak and #pragma pack.  */
  49 #define HANDLE_SYSV_PRAGMA 1
  50
  51 /* This is the only version of nm that collect2 can work with.  */
  52 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  53
  54 #define USER_LABEL_PREFIX  ""
  55
  56 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  57 #define RELATIVE_PREFIX_NOT_LINKDIR
  58
  59 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  60 #define LINK_LIBGCC_SPECIAL_1
  61
  62 #define MFWRAP_SPEC " %{static: %{fmudflap|fmudflapth: \
  63  -brename:malloc,__wrap_malloc -brename:__real_malloc,malloc \
  64  -brename:free,__wrap_free -brename:__real_free,free \
  65  -brename:calloc,__wrap_calloc -brename:__real_calloc,calloc \
  66  -brename:realloc,__wrap_realloc -brename:__real_realloc,realloc \
  67  -brename:mmap,__wrap_mmap -brename:__real_mmap,mmap \
  68  -brename:munmap,__wrap_munmap -brename:__real_munmap,munmap \
  69  -brename:alloca,__wrap_alloca -brename:__real_alloca,alloca \
  70 } %{fmudflapth: \
  71  -brename:pthread_create,__wrap_pthread_create \
  72  -brename:__real_pthread_create,pthread_create \
  73  -brename:pthread_join,__wrap_pthread_join \
  74  -brename:__real_pthread_join,pthread_join \
  75  -brename:pthread_exit,__wrap_pthread_exit \
  76  -brename:__real_pthread_exit,pthread_exit \
  77 }} %{fmudflap|fmudflapth: \
  78  -brename:main,__wrap_main -brename:__real_main,main \
  79 }"
  80
  81 #define MFLIB_SPEC " %{fmudflap: -lmudflap \
  82  %{static:%(link_gcc_c_sequence) -lmudflap}} \
  83  %{fmudflapth: -lmudflapth -lpthread \
  84  %{static:%(link_gcc_c_sequence) -lmudflapth}} "
  85
  86 /* Names to predefine in the preprocessor for this target machine.  */
  87 #define TARGET_OS_AIX_CPP_BUILTINS()            \
  88   do                                            \
  89     {                                           \
  90       builtin_define ("_IBMR2");                \
  91       builtin_define ("_POWER");                \
  92       builtin_define ("_AIX");                  \
  93       builtin_define ("_AIX32");                \
  94       builtin_define ("_AIX41");                \
  95       builtin_define ("_LONG_LONG");            \
  96       if (TARGET_LONG_DOUBLE_128)               \
  97         builtin_define ("__LONGDOUBLE128");     \
  98       builtin_assert ("system=unix");           \
  99       builtin_assert ("system=aix");            \
 100     }                                           \
 101   while (0)
 102
 103 /* Define appropriate architecture macros for preprocessor depending on
 104    target switches.  */
 105
 106 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
 107    %{ansi: -D_ANSI_C_SOURCE}"
 108
 109 #undef ASM_DEFAULT_SPEC
 110 #define ASM_DEFAULT_SPEC ""
 111
 112 /* Tell the assembler to assume that all undefined names are external.
 113
 114    Don't do this until the fixed IBM assembler is more generally available.
 115    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
 116    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
 117    longer be needed.  Also, the extern declaration of mcount in
 118    rs6000_xcoff_file_start will no longer be needed.  */
 119
 120 /* #define ASM_SPEC "-u %(asm_cpu)" */
 121
 122 /* Default location of syscalls.exp under AIX */
 123 #ifndef CROSS_COMPILE
 124 #define LINK_SYSCALLS_SPEC "-bI:/lib/syscalls.exp"
 125 #else
 126 #define LINK_SYSCALLS_SPEC ""
 127 #endif
 128
 129 /* Default location of libg.exp under AIX */
 130 #ifndef CROSS_COMPILE
 131 #define LINK_LIBG_SPEC "-bexport:/usr/lib/libg.exp"
 132 #else
 133 #define LINK_LIBG_SPEC ""
 134 #endif
 135
 136 /* Define the options for the binder: Start text at 512, align all segments
 137    to 512 bytes, and warn if there is text relocation.
 138
 139    The -bhalt:4 option supposedly changes the level at which ld will abort,
 140    but it also suppresses warnings about multiply defined symbols and is
 141    used by the AIX cc command.  So we use it here.
 142
 143    -bnodelcsect undoes a poor choice of default relating to multiply-defined
 144    csects.  See AIX documentation for more information about this.
 145
 146    -bM:SRE tells the linker that the output file is Shared REusable.  Note
 147    that to actually build a shared library you will also need to specify an
 148    export list with the -Wl,-bE option.  */
 149
 150 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\
 151 %{static:-bnso %(link_syscalls) } \
 152 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}"
 153
 154 /* Profiled library versions are used by linking with special directories.  */
 155 #define LIB_SPEC "%{pg:-L/lib/profiled -L/usr/lib/profiled}\
 156 %{p:-L/lib/profiled -L/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 157
 158 /* This now supports a natural alignment mode.  */
 159 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 160 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 161   (TARGET_ALIGN_NATURAL ? (COMPUTED) : \
 162   (TYPE_MODE (TREE_CODE (TREE_TYPE (FIELD)) == ARRAY_TYPE \
 163               ? get_inner_array_type (FIELD) \
 164               : TREE_TYPE (FIELD)) == DFmode \
 165    ? MIN ((COMPUTED), 32) : (COMPUTED)))
 166
 167 /* AIX increases natural record alignment to doubleword if the first
 168    field is an FP double while the FP fields remain word aligned.  */
 169 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)                           \
 170   ((TREE_CODE (STRUCT) == RECORD_TYPE                                           \
 171     || TREE_CODE (STRUCT) == UNION_TYPE                                         \
 172     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)                                   \
 173    && TARGET_ALIGN_NATURAL == 0                                                 \
 174    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)              \
 175    : MAX ((COMPUTED), (SPECIFIED)))
 176
 177 /* The AIX ABI isn't explicit on whether aggregates smaller than a
 178    word/doubleword should be padded upward or downward.  One could
 179    reasonably assume that they follow the normal rules for structure
 180    layout treating the parameter area as any other block of memory,
 181    then map the reg param area to registers, i.e., pad upward, which
 182    is the way IBM Compilers for AIX behave.
 183    Setting both of the following defines results in this behavior.  */
 184 #define AGGREGATE_PADDING_FIXED 1
 185 #define AGGREGATES_PAD_UPWARD_ALWAYS 1
 186
 187 /* Specify padding for the last element of a block move between
 188    registers and memory.  FIRST is nonzero if this is the only
 189    element.  */
 190 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 191   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
 192
 193 /* Indicate that jump tables go in the text section.  */
 194
 195 #define JUMP_TABLES_IN_TEXT_SECTION 1
 196
 197 /* Enable AIX XL compiler calling convention breakage compatibility.  */
 198 #undef TARGET_XL_COMPAT
 199 #define MASK_XL_COMPAT          0x40000000
 200 #define TARGET_XL_COMPAT        (target_flags & MASK_XL_COMPAT)
 201 #undef  SUBTARGET_SWITCHES
 202 #define SUBTARGET_SWITCHES              \
 203   {"xl-compat",         MASK_XL_COMPAT,                                 \
 204    N_("Conform more closely to IBM XLC semantics") },           \
 205   {"no-xl-compat",      - MASK_XL_COMPAT,                                       \
 206    N_("Default GCC semantics that differ from IBM XLC") },      \
 207   SUBSUBTARGET_SWITCHES
 208 #define SUBSUBTARGET_SWITCHES
 209
 210 /* Define any extra SPECS that the compiler needs to generate.  */
 211 #undef  SUBTARGET_EXTRA_SPECS
 212 #define SUBTARGET_EXTRA_SPECS                                           \
 213   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 214   { "link_libg",                LINK_LIBG_SPEC }
 215
 216 /* Define cutoff for using external functions to save floating point.  */
 217 #define FP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) == 62 || (FIRST_REG) == 63)
 218
 219 /* __throw will restore its own return address to be the same as the
 220    return address of the function that the throw is being made to.
 221    This is unfortunate, because we want to check the original
 222    return address to see if we need to restore the TOC.
 223    So we have to squirrel it away with this.  */
 224 #define SETUP_FRAME_ADDRESSES() rs6000_aix_emit_builtin_unwind_init ()
 225
 226 /* If the current unwind info (FS) does not contain explicit info
 227    saving R2, then we have to do a minor amount of code reading to
 228    figure out if it was saved.  The big problem here is that the
 229    code that does the save/restore is generated by the linker, so
 230    we have no good way to determine at compile time what to do.  */
 231
 232 #ifdef __64BIT__
 233 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 234   do {                                                                  \
 235     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 236       {                                                                 \
 237         unsigned int *insn                                              \
 238           = (unsigned int *)                                            \
 239             _Unwind_GetGR ((CTX), LINK_REGISTER_REGNUM);                \
 240         if (*insn == 0xE8410028)                                        \
 241           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 40);                 \
 242       }                                                                 \
 243   } while (0)
 244 #else
 245 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 246   do {                                                                  \
 247     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 248       {                                                                 \
 249         unsigned int *insn                                              \
 250           = (unsigned int *)                                            \
 251             _Unwind_GetGR ((CTX), LINK_REGISTER_REGNUM);                \
 252         if (*insn == 0x80410014)                                        \
 253           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 20);                 \
 254       }                                                                 \
 255   } while (0)
 256 #endif
 257
 258 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)
 259
 260 /* Print subsidiary information on the compiler version in use.  */
 261 #define TARGET_VERSION ;
 262
 263 /* No version of AIX fully supports AltiVec or 64-bit instructions in
 264    32-bit mode.  */
 265 #define OS_MISSING_POWERPC64 1
 266 #define OS_MISSING_ALTIVEC 1
 267
 268 /* WINT_TYPE */
 269 #define WINT_TYPE "int"