gcc/config/rs6000/aix.h

   1 /* Definitions of target machine for GNU compiler,
   2    for IBM RS/6000 POWER running AIX.
   3    Copyright (C) 2000-2013 Free Software Foundation, Inc.
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published
   9    by the Free Software Foundation; either version 3, or (at your
  10    option) any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GCC; see the file COPYING3.  If not see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 /* Yes!  We are AIX!  */
  22 #define DEFAULT_ABI ABI_AIX
  23 #undef  TARGET_AIX
  24 #define TARGET_AIX 1
  25
  26 /* Linux64.h wants to redefine TARGET_AIX based on -m64, but it can't be used
  27    in the #if conditional in options-default.h, so provide another macro.  */
  28 #undef  TARGET_AIX_OS
  29 #define TARGET_AIX_OS 1
  30
  31 /* AIX always has a TOC.  */
  32 #define TARGET_NO_TOC 0
  33 #define TARGET_TOC 1
  34 #define FIXED_R2 1
  35
  36 /* AIX allows r13 to be used in 32-bit mode.  */
  37 #define FIXED_R13 0
  38
  39 /* 32-bit and 64-bit AIX stack boundary is 128.  */
  40 #undef  STACK_BOUNDARY
  41 #define STACK_BOUNDARY 128
  42
  43 #undef  TARGET_IEEEQUAD
  44 #define TARGET_IEEEQUAD 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 #if HAVE_AS_REF
  51 /* Issue assembly directives that create a reference to the given DWARF table
  52    identifier label from the current function section.  This is defined to
  53    ensure we drag frame frame tables associated with needed function bodies in
  54    a link with garbage collection activated.  */
  55 #define ASM_OUTPUT_DWARF_TABLE_REF rs6000_aix_asm_output_dwarf_table_ref
  56 #endif
  57
  58 /* This is the only version of nm that collect2 can work with.  */
  59 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  60
  61 #define USER_LABEL_PREFIX  ""
  62
  63 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  64 #define RELATIVE_PREFIX_NOT_LINKDIR
  65
  66 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  67 #define LINK_LIBGCC_SPECIAL_1
  68
  69 /* Names to predefine in the preprocessor for this target machine.  */
  70 #define TARGET_OS_AIX_CPP_BUILTINS()            \
  71   do                                            \
  72     {                                           \
  73       builtin_define ("_IBMR2");                \
  74       builtin_define ("_POWER");                \
  75       builtin_define ("__powerpc__");           \
  76       builtin_define ("__PPC__");               \
  77       builtin_define ("__unix__");              \
  78       builtin_define ("_AIX");                  \
  79       builtin_define ("_AIX32");                \
  80       builtin_define ("_AIX41");                \
  81       builtin_define ("_LONG_LONG");            \
  82       if (TARGET_LONG_DOUBLE_128)               \
  83         builtin_define ("__LONGDOUBLE128");     \
  84       builtin_assert ("system=unix");           \
  85       builtin_assert ("system=aix");            \
  86     }                                           \
  87   while (0)
  88
  89 /* Define appropriate architecture macros for preprocessor depending on
  90    target switches.  */
  91
  92 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
  93    %{ansi: -D_ANSI_C_SOURCE}"
  94
  95 #define CC1_SPEC "%(cc1_cpu)"
  96
  97 #undef ASM_DEFAULT_SPEC
  98 #define ASM_DEFAULT_SPEC ""
  99
 100 /* Tell the assembler to assume that all undefined names are external.
 101
 102    Don't do this until the fixed IBM assembler is more generally available.
 103    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
 104    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
 105    longer be needed.  Also, the extern declaration of mcount in
 106    rs6000_xcoff_file_start will no longer be needed.  */
 107
 108 /* #define ASM_SPEC "-u %(asm_cpu)" */
 109
 110 /* Default location of syscalls.exp under AIX */
 111 #define LINK_SYSCALLS_SPEC "-bI:%R/lib/syscalls.exp"
 112
 113 /* Default location of libg.exp under AIX */
 114 #define LINK_LIBG_SPEC "-bexport:%R/usr/lib/libg.exp"
 115
 116 /* Define the options for the binder: Start text at 512, align all segments
 117    to 512 bytes, and warn if there is text relocation.
 118
 119    The -bhalt:4 option supposedly changes the level at which ld will abort,
 120    but it also suppresses warnings about multiply defined symbols and is
 121    used by the AIX cc command.  So we use it here.
 122
 123    -bnodelcsect undoes a poor choice of default relating to multiply-defined
 124    csects.  See AIX documentation for more information about this.
 125
 126    -bM:SRE tells the linker that the output file is Shared REusable.  Note
 127    that to actually build a shared library you will also need to specify an
 128    export list with the -Wl,-bE option.  */
 129
 130 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\
 131 %{static:-bnso %(link_syscalls) } \
 132 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}"
 133
 134 /* Profiled library versions are used by linking with special directories.  */
 135 #define LIB_SPEC "%{pg:-L%R/lib/profiled -L%R/usr/lib/profiled}\
 136 %{p:-L%R/lib/profiled -L%R/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 137
 138 /* Static linking with shared libstdc++ requires libsupc++ as well.  */
 139 #define LIBSTDCXX_STATIC "supc++"
 140
 141 /* This now supports a natural alignment mode.  */
 142 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 143 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 144   ((TARGET_ALIGN_NATURAL == 0                                           \
 145     && TYPE_MODE (strip_array_types (TREE_TYPE (FIELD))) == DFmode)     \
 146    ? MIN ((COMPUTED), 32)                                               \
 147    : (COMPUTED))
 148
 149 /* AIX increases natural record alignment to doubleword if the first
 150    field is an FP double while the FP fields remain word aligned.  */
 151 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)                   \
 152   ((TREE_CODE (STRUCT) == RECORD_TYPE                                   \
 153     || TREE_CODE (STRUCT) == UNION_TYPE                                 \
 154     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)                           \
 155    && TARGET_ALIGN_NATURAL == 0                                         \
 156    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)      \
 157    : MAX ((COMPUTED), (SPECIFIED)))
 158
 159 /* The AIX ABI isn't explicit on whether aggregates smaller than a
 160    word/doubleword should be padded upward or downward.  One could
 161    reasonably assume that they follow the normal rules for structure
 162    layout treating the parameter area as any other block of memory,
 163    then map the reg param area to registers, i.e., pad upward, which
 164    is the way IBM Compilers for AIX behave.
 165    Setting both of the following defines results in this behavior.  */
 166 #define AGGREGATE_PADDING_FIXED 1
 167 #define AGGREGATES_PAD_UPWARD_ALWAYS 1
 168
 169 /* Specify padding for the last element of a block move between
 170    registers and memory.  FIRST is nonzero if this is the only
 171    element.  */
 172 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 173   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
 174
 175 /* Indicate that jump tables go in the text section.  */
 176
 177 #define JUMP_TABLES_IN_TEXT_SECTION 1
 178
 179 /* Define any extra SPECS that the compiler needs to generate.  */
 180 #undef  SUBTARGET_EXTRA_SPECS
 181 #define SUBTARGET_EXTRA_SPECS                                           \
 182   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 183   { "link_libg",                LINK_LIBG_SPEC }
 184
 185 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)
 186
 187 /* No version of AIX fully supports AltiVec or 64-bit instructions in
 188    32-bit mode.  */
 189 #define OS_MISSING_POWERPC64 1
 190 #define OS_MISSING_ALTIVEC 1
 191
 192 /* WINT_TYPE */
 193 #define WINT_TYPE "int"
 194
 195 /* Static stack checking is supported by means of probes.  */
 196 #define STACK_CHECK_STATIC_BUILTIN 1