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, 2008, 2010,
   4    2011 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 /* Linux64.h wants to redefine TARGET_AIX based on -m64, but it can't be used
  28    in the #if conditional in options-default.h, so provide another macro.  */
  29 #undef  TARGET_AIX_OS
  30 #define TARGET_AIX_OS 1
  31
  32 /* AIX always has a TOC.  */
  33 #define TARGET_NO_TOC 0
  34 #define TARGET_TOC 1
  35 #define FIXED_R2 1
  36
  37 /* AIX allows r13 to be used in 32-bit mode.  */
  38 #define FIXED_R13 0
  39
  40 /* 32-bit and 64-bit AIX stack boundary is 128.  */
  41 #undef  STACK_BOUNDARY
  42 #define STACK_BOUNDARY 128
  43
  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 #if HAVE_AS_REF
  52 /* Issue assembly directives that create a reference to the given DWARF table
  53    identifier label from the current function section.  This is defined to
  54    ensure we drag frame frame tables associated with needed function bodies in
  55    a link with garbage collection activated.  */
  56 #define ASM_OUTPUT_DWARF_TABLE_REF rs6000_aix_asm_output_dwarf_table_ref
  57 #endif
  58
  59 /* This is the only version of nm that collect2 can work with.  */
  60 #define REAL_NM_FILE_NAME "/usr/ucb/nm"
  61
  62 #define USER_LABEL_PREFIX  ""
  63
  64 /* Don't turn -B into -L if the argument specifies a relative file name.  */
  65 #define RELATIVE_PREFIX_NOT_LINKDIR
  66
  67 /* Because of the above, we must have gcc search itself to find libgcc.a.  */
  68 #define LINK_LIBGCC_SPECIAL_1
  69
  70 #define MFWRAP_SPEC " %{static: %{fmudflap|fmudflapth: \
  71  -brename:malloc,__wrap_malloc -brename:__real_malloc,malloc \
  72  -brename:free,__wrap_free -brename:__real_free,free \
  73  -brename:calloc,__wrap_calloc -brename:__real_calloc,calloc \
  74  -brename:realloc,__wrap_realloc -brename:__real_realloc,realloc \
  75  -brename:mmap,__wrap_mmap -brename:__real_mmap,mmap \
  76  -brename:munmap,__wrap_munmap -brename:__real_munmap,munmap \
  77  -brename:alloca,__wrap_alloca -brename:__real_alloca,alloca \
  78 } %{fmudflapth: \
  79  -brename:pthread_create,__wrap_pthread_create \
  80  -brename:__real_pthread_create,pthread_create \
  81  -brename:pthread_join,__wrap_pthread_join \
  82  -brename:__real_pthread_join,pthread_join \
  83  -brename:pthread_exit,__wrap_pthread_exit \
  84  -brename:__real_pthread_exit,pthread_exit \
  85 }} %{fmudflap|fmudflapth: \
  86  -brename:main,__wrap_main -brename:__real_main,main \
  87 }"
  88
  89 #define MFLIB_SPEC " %{fmudflap: -lmudflap \
  90  %{static:%(link_gcc_c_sequence) -lmudflap}} \
  91  %{fmudflapth: -lmudflapth -lpthread \
  92  %{static:%(link_gcc_c_sequence) -lmudflapth}} "
  93
  94 /* Names to predefine in the preprocessor for this target machine.  */
  95 #define TARGET_OS_AIX_CPP_BUILTINS()            \
  96   do                                            \
  97     {                                           \
  98       builtin_define ("_IBMR2");                \
  99       builtin_define ("_POWER");                \
 100       builtin_define ("_AIX");                  \
 101       builtin_define ("_AIX32");                \
 102       builtin_define ("_AIX41");                \
 103       builtin_define ("_LONG_LONG");            \
 104       if (TARGET_LONG_DOUBLE_128)               \
 105         builtin_define ("__LONGDOUBLE128");     \
 106       builtin_assert ("system=unix");           \
 107       builtin_assert ("system=aix");            \
 108     }                                           \
 109   while (0)
 110
 111 /* Define appropriate architecture macros for preprocessor depending on
 112    target switches.  */
 113
 114 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\
 115    %{ansi: -D_ANSI_C_SOURCE}"
 116
 117 #define CC1_SPEC "%(cc1_cpu)"
 118
 119 #undef ASM_DEFAULT_SPEC
 120 #define ASM_DEFAULT_SPEC ""
 121
 122 /* Tell the assembler to assume that all undefined names are external.
 123
 124    Don't do this until the fixed IBM assembler is more generally available.
 125    When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL,
 126    ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no
 127    longer be needed.  Also, the extern declaration of mcount in
 128    rs6000_xcoff_file_start will no longer be needed.  */
 129
 130 /* #define ASM_SPEC "-u %(asm_cpu)" */
 131
 132 /* Default location of syscalls.exp under AIX */
 133 #define LINK_SYSCALLS_SPEC "-bI:%R/lib/syscalls.exp"
 134
 135 /* Default location of libg.exp under AIX */
 136 #define LINK_LIBG_SPEC "-bexport:%R/usr/lib/libg.exp"
 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%R/lib/profiled -L%R/usr/lib/profiled}\
 158 %{p:-L%R/lib/profiled -L%R/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc"
 159
 160 /* Static linking with shared libstdc++ requires libsupc++ as well.  */
 161 #define LIBSTDCXX_STATIC "supc++"
 162
 163 /* This now supports a natural alignment mode.  */
 164 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints.  */
 165 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
 166   ((TARGET_ALIGN_NATURAL == 0                                           \
 167     && TYPE_MODE (strip_array_types (TREE_TYPE (FIELD))) == DFmode)     \
 168    ? MIN ((COMPUTED), 32)                                               \
 169    : (COMPUTED))
 170
 171 /* AIX increases natural record alignment to doubleword if the first
 172    field is an FP double while the FP fields remain word aligned.  */
 173 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)                   \
 174   ((TREE_CODE (STRUCT) == RECORD_TYPE                                   \
 175     || TREE_CODE (STRUCT) == UNION_TYPE                                 \
 176     || TREE_CODE (STRUCT) == QUAL_UNION_TYPE)                           \
 177    && TARGET_ALIGN_NATURAL == 0                                         \
 178    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)      \
 179    : MAX ((COMPUTED), (SPECIFIED)))
 180
 181 /* The AIX ABI isn't explicit on whether aggregates smaller than a
 182    word/doubleword should be padded upward or downward.  One could
 183    reasonably assume that they follow the normal rules for structure
 184    layout treating the parameter area as any other block of memory,
 185    then map the reg param area to registers, i.e., pad upward, which
 186    is the way IBM Compilers for AIX behave.
 187    Setting both of the following defines results in this behavior.  */
 188 #define AGGREGATE_PADDING_FIXED 1
 189 #define AGGREGATES_PAD_UPWARD_ALWAYS 1
 190
 191 /* Specify padding for the last element of a block move between
 192    registers and memory.  FIRST is nonzero if this is the only
 193    element.  */
 194 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 195   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
 196
 197 /* Indicate that jump tables go in the text section.  */
 198
 199 #define JUMP_TABLES_IN_TEXT_SECTION 1
 200
 201 /* Define any extra SPECS that the compiler needs to generate.  */
 202 #undef  SUBTARGET_EXTRA_SPECS
 203 #define SUBTARGET_EXTRA_SPECS                                           \
 204   { "link_syscalls",            LINK_SYSCALLS_SPEC },                   \
 205   { "link_libg",                LINK_LIBG_SPEC }
 206
 207 /* Define cutoff for using external functions to save floating point.  */
 208 #define FP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) == 62 || (FIRST_REG) == 63)
 209 /* And similarly for general purpose registers.  */
 210 #define GP_SAVE_INLINE(FIRST_REG) ((FIRST_REG) < 32)
 211
 212 /* If the current unwind info (FS) does not contain explicit info
 213    saving R2, then we have to do a minor amount of code reading to
 214    figure out if it was saved.  The big problem here is that the
 215    code that does the save/restore is generated by the linker, so
 216    we have no good way to determine at compile time what to do.  */
 217
 218 #define R_LR 65
 219
 220 #ifdef __64BIT__
 221 #define MD_FROB_UPDATE_CONTEXT(CTX, FS)                                 \
 222   do {                                                                  \
 223     if ((FS)->regs.reg[2].how == REG_UNSAVED)                           \
 224       {                                                                 \
 225         unsigned int *insn                                              \
 226           = (unsigned int *)                                            \
 227             _Unwind_GetGR ((CTX), R_LR);                                \
 228         if (*insn == 0xE8410028)                                        \
 229           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 40);                 \
 230       }                                                                 \
 231   } while (0)
 232 #else
 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), R_LR);                                \
 240         if (*insn == 0x80410014)                                        \
 241           _Unwind_SetGRPtr ((CTX), 2, (CTX)->cfa + 20);                 \
 242       }                                                                 \
 243   } while (0)
 244 #endif
 245
 246 #define PROFILE_HOOK(LABEL)   output_profile_hook (LABEL)
 247
 248 /* No version of AIX fully supports AltiVec or 64-bit instructions in
 249    32-bit mode.  */
 250 #define OS_MISSING_POWERPC64 1
 251 #define OS_MISSING_ALTIVEC 1
 252
 253 /* WINT_TYPE */
 254 #define WINT_TYPE "int"
 255
 256 /* Static stack checking is supported by means of probes.  */
 257 #define STACK_CHECK_STATIC_BUILTIN 1