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 Free Software Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 /* Yes!  We are AIX!  */
  23 #define DEFAULT_ABI ABI_AIX
  24 #undef TARGET_AIX
  25 #define TARGET_AIX 1
  26 /* The AIX linker will discard static constructors in object files before
  27    collect has a chance to see them, so scan the object files directly.  */
  28 #define COLLECT_EXPORT_LIST
  29
  30 /* This is the only version of nm that collect2 can work with.  */
  31 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  32
  33 #define USER_LABEL_PREFIX  ""
  34 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  35 #define RELATIVE_PREFIX_NOT_LINKDIR
  36
  37 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  38 #define LINK_LIBGCC_SPECIAL_1
  39
  40 /* Names to predefine in the preprocessor for this target machine.  */
  41 #define CPP_PREDEFINES "-D_IBMR2 -D_POWER -D_AIX -D_AIX32 -D_LONG_LONG \
  42 -Asystem=unix -Asystem=aix -Acpu=rs6000 -Amachine=rs6000"
  43
  44 /* Define appropriate architecture macros for preprocessor depending on
  45    target switches.  */
  46
  47 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
  48    %{ansi: -D_ANSI_C_SOURCE}\
  49    %(cpp_cpu)"
  50
  51 #undef CPP_DEFAULT_SPEC
  52 #define CPP_DEFAULT_SPEC "-D_ARCH_PWR"
  53
  54 #undef ASM_DEFAULT_SPEC
  55 #define ASM_DEFAULT_SPEC ""
  56
  57 /* Tell the assembler to assume that all undefined names are external.
  58
  59    Don't do this until the fixed IBM assembler is more generally available.
  60    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
  61    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
  62    longer be needed.  Also, the extern declaration of mcount in ASM_FILE_START
  63    will no longer be needed.  */
  64
  65 /* #define ASM_SPEC "-u %(asm_cpu)" */
  66
  67 /* Default location of syscalls.exp under AIX */
  68 #ifndef CROSS_COMPILE
  69 #define LINK_SYSCALLS_SPEC "-bI:/lib/syscalls.exp"
  70 #else
  71 #define LINK_SYSCALLS_SPEC ""
  72 #endif
  73
  74 /* Default location of libg.exp under AIX */
  75 #ifndef CROSS_COMPILE
  76 #define LINK_LIBG_SPEC "-bexport:/usr/lib/libg.exp"
  77 #else
  78 #define LINK_LIBG_SPEC ""
  79 #endif
  80
  81 /* Define the options for the binder: Start text at 512, align all segments
  82    to 512 bytes, and warn if there is text relocation.
  83
  84    The -bhalt:4 option supposedly changes the level at which ld will abort,
  85    but it also suppresses warnings about multiply defined symbols and is
  86    used by the AIX cc command.  So we use it here.
  87
  88    -bnodelcsect undoes a poor choice of default relating to multiply-defined
  89    csects.  See AIX documentation for more information about this.
  90
  91    -bM:SRE tells the linker that the output file is Shared REusable.  Note
  92    that to actually build a shared library you will also need to specify an
  93    export list with the -Wl,-bE option.  */
  94
  95 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\
  96 %{static:-bnso %(link_syscalls) } \
  97 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}"
  98
  99 /* Profiled library versions are used by linking with special directories.  */
 100 #define LIB_SPEC "%{pg:-L/lib/profiled -L/usr/lib/profiled}\
 101 %{p:-L/lib/profiled -L/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 102
 103 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 104 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 105   (TYPE_MODE (TREE_CODE (TREE_TYPE (FIELD)) == ARRAY_TYPE \
 106               ? get_inner_array_type (FIELD) \
 107               : TREE_TYPE (FIELD)) == DFmode \
 108    ? MIN ((COMPUTED), 32) : (COMPUTED))
 109
 110 /* AIX increases natural record alignment to doubleword if the first
 111    field is an FP double while the FP fields remain word aligned.  */
 112 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)   \
 113   ((TREE_CODE (STRUCT) == RECORD_TYPE                   \
 114     || TREE_CODE (STRUCT) == UNION_TYPE                 \
 115     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)           \
 116    && TYPE_FIELDS (STRUCT) != 0                         \
 117    && DECL_MODE (TYPE_FIELDS (STRUCT)) == DFmode        \
 118    ? MAX (MAX ((COMPUTED), (SPECIFIED)), BIGGEST_ALIGNMENT) \
 119    : MAX ((COMPUTED), (SPECIFIED)))
 120
 121
 122
 123 /* Indicate that jump tables go in the text section.  */
 124
 125 #define JUMP_TABLES_IN_TEXT_SECTION 1
 126
 127 /* Enable AIX XL compiler calling convention breakage compatibility.  */
 128 #undef TARGET_XL_CALL
 129 #define MASK_XL_CALL            0x40000000
 130 #define TARGET_XL_CALL          (target_flags & MASK_XL_CALL)
 131 #undef  SUBTARGET_SWITCHES
 132 #define SUBTARGET_SWITCHES              \
 133   {"xl-call",           MASK_XL_CALL,                                   \
 134    N_("Always pass floating-point arguments in memory") },              \
 135   {"no-xl-call",        - MASK_XL_CALL,                                 \
 136    N_("Don't always pass floating-point arguments in memory") },        \
 137   SUBSUBTARGET_SWITCHES
 138 #define SUBSUBTARGET_SWITCHES
 139
 140 /* Define any extra SPECS that the compiler needs to generate.  */
 141 #undef  SUBTARGET_EXTRA_SPECS
 142 #define SUBTARGET_EXTRA_SPECS                                           \
 143   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 144   { "link_libg",                LINK_LIBG_SPEC }
 145
 146 /* Define cutoff for using external functions to save floating point.  */
 147 #define FP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) == 62 || (FIRST_REG) == 63)
 148
 149 /* Optabs entries for the int->float routines and quad FP operations
 150    using the standard AIX names.  */
 151 #define ADDTF3_LIBCALL "_xlqadd"
 152 #define DIVTF3_LIBCALL "_xlqdiv"
 153 #define MULTF3_LIBCALL "_xlqmul"
 154 #define SUBTF3_LIBCALL "_xlqsub"
 155
 156 #define INIT_TARGET_OPTABS                                              \
 157   do {                                                                  \
 158     if (! TARGET_POWER2 && ! TARGET_POWERPC && TARGET_HARD_FLOAT)       \
 159       {                                                                 \
 160         fixdfsi_libfunc = init_one_libfunc (RS6000_ITRUNC);             \
 161         fixunsdfsi_libfunc = init_one_libfunc (RS6000_UITRUNC);         \
 162       }                                                                 \
 163     if (TARGET_HARD_FLOAT)                                              \
 164       {                                                                 \
 165         add_optab->handlers[(int) TFmode].libfunc                       \
 166           = init_one_libfunc (ADDTF3_LIBCALL);                          \
 167         sub_optab->handlers[(int) TFmode].libfunc                       \
 168           = init_one_libfunc (SUBTF3_LIBCALL);                          \
 169         smul_optab->handlers[(int) TFmode].libfunc                      \
 170           = init_one_libfunc (MULTF3_LIBCALL);                          \
 171         sdiv_optab->handlers[(int) TFmode].libfunc                      \
 172           = init_one_libfunc (DIVTF3_LIBCALL);                          \
 173       }                                                                 \
 174   } while (0)
 175
 176 /* AIX always has a TOC.  */
 177 #define TARGET_NO_TOC           0
 178 #define TARGET_TOC              1
 179
 180 #define FIXED_R2 1
 181 /* AIX allows r13 to be used.  */
 182 #define FIXED_R13 0
 183
 184 /* __throw will restore its own return address to be the same as the
 185    return address of the function that the throw is being made to.
 186    This is unfortunate, because we want to check the original
 187    return address to see if we need to restore the TOC.
 188    So we have to squirrel it away with this.  */
 189 #define SETUP_FRAME_ADDRESSES() rs6000_aix_emit_builtin_unwind_init ()
 190
 191 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)