gcc/config/alpha/osf.h

   1 /* Definitions of target machine for GNU compiler, for DEC Alpha on OSF/1.
   2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 2001, 2002, 2003
   3    Free Software Foundation, Inc.
   4    Contributed by Richard Kenner (kenner@vlsi1.ultra.nyu.edu)
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public 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
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.  */
  22
  23 /* As of OSF 4.0, as can subtract adjacent labels.  */
  24
  25 #undef TARGET_AS_CAN_SUBTRACT_LABELS
  26 #define TARGET_AS_CAN_SUBTRACT_LABELS 1
  27
  28 /* The GEM libraries for X_float are present, though not used by C.  */
  29
  30 #undef TARGET_HAS_XFLOATING_LIBS
  31 #define TARGET_HAS_XFLOATING_LIBS 1
  32
  33 /* Names to predefine in the preprocessor for this target machine.  */
  34
  35 #define TARGET_OS_CPP_BUILTINS()                        \
  36     do {                                                \
  37         builtin_define_std ("unix");                    \
  38         builtin_define_std ("SYSTYPE_BSD");             \
  39         builtin_define ("_SYSTYPE_BSD");                \
  40         builtin_define ("__osf__");                     \
  41         builtin_define ("__digital__");                 \
  42         builtin_define ("__arch64__");                  \
  43         builtin_define ("_LONGLONG");                   \
  44         builtin_define ("__PRAGMA_EXTERN_PREFIX");      \
  45         builtin_assert ("system=unix");                 \
  46         builtin_assert ("system=xpg4");                 \
  47         /* Tru64 UNIX V5 has a 16 byte long             \
  48            double type and requires __X_FLOAT           \
  49            to be defined for <math.h>.  */              \
  50         if (LONG_DOUBLE_TYPE_SIZE == 128)               \
  51           builtin_define ("__X_FLOAT");                 \
  52                                                         \
  53         /* Tru64 UNIX V4/V5 provide several ISO C94     \
  54            features protected by the corresponding      \
  55            __STDC_VERSION__ macro.  libstdc++ v3        \
  56            needs them as well.  */                      \
  57         if (c_dialect_cxx ())                           \
  58           builtin_define ("__STDC_VERSION__=199409L");  \
  59     } while (0)
  60
  61 /* Accept DEC C flags for multithreaded programs.  We use _PTHREAD_USE_D4
  62    instead of PTHREAD_USE_D4 since both have the same effect and the former
  63    doesn't invade the users' namespace.  */
  64
  65 #undef CPP_SUBTARGET_SPEC
  66 #define CPP_SUBTARGET_SPEC \
  67 "%{pthread|threads:-D_REENTRANT} %{threads:-D_PTHREAD_USE_D4}"
  68
  69 /* Under OSF4, -p and -pg require -lprof1, and -lprof1 requires -lpdf.  */
  70
  71 #define LIB_SPEC \
  72 "%{p|pg:-lprof1%{pthread|threads:_r} -lpdf} %{a:-lprof2} \
  73  %{threads: -lpthreads} %{pthread|threads: -lpthread -lmach -lexc} -lc"
  74
  75 /* Pass "-G 8" to ld because Alpha's CC does.  Pass -O3 if we are
  76    optimizing, -O1 if we are not.  Pass -S to silence `weak symbol
  77    multiply defined' warnings.  Pass -shared, -non_shared or
  78    -call_shared as appropriate.  Pass -hidden_symbol so that our
  79    constructor and call-frame data structures are not accidentally
  80    overridden.  */
  81 #define LINK_SPEC  \
  82   "-G 8 %{O*:-O3} %{!O*:-O1} -S %{static:-non_shared} \
  83    %{!static:%{shared:-shared -hidden_symbol _GLOBAL_*} \
  84    %{!shared:-call_shared}} %{pg} %{taso} %{rpath*}"
  85
  86 #define STARTFILE_SPEC  \
  87   "%{!shared:%{pg:gcrt0.o%s}%{!pg:%{p:mcrt0.o%s}%{!p:crt0.o%s}}}"
  88
  89 #define ENDFILE_SPEC \
  90   "%{ffast-math|funsafe-math-optimizations:crtfastmath.o%s}"
  91
  92 #define MD_STARTFILE_PREFIX "/usr/lib/cmplrs/cc/"
  93
  94 /* Tru64 UNIX V5.1 requires a special as flag.  Empty by default.  */
  95
  96 #define ASM_OLDAS_SPEC ""
  97
  98 /* In OSF/1 v3.2c, the assembler by default does not output file names which
  99    causes mips-tfile to fail.  Passing -g to the assembler fixes this problem.
 100    ??? Strictly speaking, we need -g only if the user specifies -g.  Passing
 101    it always means that we get slightly larger than necessary object files
 102    if the user does not specify -g.  If we don't pass -g, then mips-tfile
 103    will need to be fixed to work in this case.  Pass -O0 since some
 104    optimization are broken and don't help us anyway.  Pass -nocpp because
 105    there's no point in running CPP on our assembler output.  */
 106 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 107 #define ASM_SPEC "%{malpha-as:-g %(asm_oldas) -nocpp %{pg} -O0}"
 108 #else
 109 #define ASM_SPEC "%{!mgas:-g %(asm_oldas) -nocpp %{pg} -O0}"
 110 #endif
 111
 112 /* Specify to run a post-processor, mips-tfile after the assembler
 113    has run to stuff the ecoff debug information into the object file.
 114    This is needed because the Alpha assembler provides no way
 115    of specifying such information in the assembly file.  */
 116
 117 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 118
 119 #define ASM_FINAL_SPEC "\
 120 %{malpha-as: %{!mno-mips-tfile: \
 121         \n mips-tfile %{v*: -v} \
 122                 %{K: -I %b.o~} \
 123                 %{!K: %{save-temps: -I %b.o~}} \
 124                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 125                 %{.s:%i} %{!.s:%g.s}}}"
 126
 127 #else
 128 #define ASM_FINAL_SPEC "\
 129 %{!mgas: %{!mno-mips-tfile: \
 130         \n mips-tfile %{v*: -v} \
 131                 %{K: -I %b.o~} \
 132                 %{!K: %{save-temps: -I %b.o~}} \
 133                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 134                 %{.s:%i} %{!.s:%g.s}}}"
 135
 136 #endif
 137
 138 #undef SUBTARGET_EXTRA_SPECS
 139 #define SUBTARGET_EXTRA_SPECS { "asm_oldas", ASM_OLDAS_SPEC }
 140
 141 /* Indicate that we have a stamp.h to use.  */
 142 #ifndef CROSS_COMPILE
 143 #define HAVE_STAMP_H 1
 144 #endif
 145
 146 /* Attempt to turn on access permissions for the stack.  */
 147
 148 #define TRANSFER_FROM_TRAMPOLINE                                        \
 149 void                                                                    \
 150 __enable_execute_stack (void *addr)                                     \
 151 {                                                                       \
 152   extern int mprotect (const void *, size_t, int);                      \
 153   long size = getpagesize ();                                           \
 154   long mask = ~(size-1);                                                \
 155   char *page = (char *) (((long) addr) & mask);                         \
 156   char *end  = (char *) ((((long) (addr + TRAMPOLINE_SIZE)) & mask) + size); \
 157                                                                         \
 158   /* 7 is PROT_READ | PROT_WRITE | PROT_EXEC */                         \
 159   if (mprotect (page, end - page, 7) < 0)                               \
 160     perror ("mprotect of trampoline code");                             \
 161 }
 162
 163 /* Digital UNIX V4.0E (1091)/usr/include/sys/types.h 4.3.49.9 1997/08/14 */
 164 #define SIZE_TYPE       "long unsigned int"
 165 #define PTRDIFF_TYPE    "long int"
 166
 167 /* The linker will stick __main into the .init section.  */
 168 #define HAS_INIT_SECTION
 169 #define LD_INIT_SWITCH "-init"
 170 #define LD_FINI_SWITCH "-fini"
 171
 172 /* Select a format to encode pointers in exception handling data.  CODE
 173    is 0 for data, 1 for code labels, 2 for function pointers.  GLOBAL is
 174    true if the symbol may be affected by dynamic relocations.
 175
 176    We really ought to be using the SREL32 relocations that ECOFF has,
 177    but no version of the native assembler supports creating such things,
 178    and Compaq has no plans to rectify this.  Worse, the dynamic loader
 179    cannot handle unaligned relocations, so we have to make sure that
 180    things get padded appropriately.  */
 181 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)                            \
 182   (TARGET_GAS                                                                \
 183    ? (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4) \
 184    : DW_EH_PE_aligned)
 185
 186 /* This is how we tell the assembler that a symbol is weak.  */
 187
 188 #define ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, VALUE)        \
 189   do                                                    \
 190     {                                                   \
 191       (*targetm.asm_out.globalize_label) (FILE, NAME);  \
 192       fputs ("\t.weakext\t", FILE);                     \
 193       assemble_name (FILE, NAME);                       \
 194       if (VALUE)                                        \
 195         {                                               \
 196           fputc (' ', FILE);                            \
 197           assemble_name (FILE, VALUE);                  \
 198         }                                               \
 199       fputc ('\n', FILE);                               \
 200     }                                                   \
 201   while (0)
 202
 203 #define ASM_WEAKEN_LABEL(FILE, NAME) ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, 0)
 204
 205 /* Handle #pragma weak and #pragma pack.  */
 206 #define HANDLE_SYSV_PRAGMA 1
 207
 208 /* Handle #pragma extern_prefix.  Technically only needed for Tru64 5.x,
 209    but easier to manipulate preprocessor bits from here.  */
 210 #define HANDLE_PRAGMA_EXTERN_PREFIX 1