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    2004, 2007 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 3, 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 COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 /* As of OSF 4.0, as can subtract adjacent labels.  */
  23
  24 #undef TARGET_AS_CAN_SUBTRACT_LABELS
  25 #define TARGET_AS_CAN_SUBTRACT_LABELS 1
  26
  27 /* The GEM libraries for X_float are present, though not used by C.  */
  28
  29 #undef TARGET_HAS_XFLOATING_LIBS
  30 #define TARGET_HAS_XFLOATING_LIBS 1
  31
  32 /* Names to predefine in the preprocessor for this target machine.  */
  33
  34 #define TARGET_OS_CPP_BUILTINS()                        \
  35     do {                                                \
  36         builtin_define_std ("unix");                    \
  37         builtin_define_std ("SYSTYPE_BSD");             \
  38         builtin_define ("_SYSTYPE_BSD");                \
  39         builtin_define ("__osf__");                     \
  40         builtin_define ("__digital__");                 \
  41         builtin_define ("__arch64__");                  \
  42         builtin_define ("_LONGLONG");                   \
  43         builtin_assert ("system=unix");                 \
  44         builtin_assert ("system=xpg4");                 \
  45         /* Tru64 UNIX V5 has a 16 byte long             \
  46            double type and requires __X_FLOAT           \
  47            to be defined for <math.h>.  */              \
  48         if (LONG_DOUBLE_TYPE_SIZE == 128)               \
  49           builtin_define ("__X_FLOAT");                 \
  50                                                         \
  51         /* Tru64 UNIX V4/V5 provide several ISO C94     \
  52            features protected by the corresponding      \
  53            __STDC_VERSION__ macro.  libstdc++ v3        \
  54            needs them as well.  */                      \
  55         if (c_dialect_cxx ())                           \
  56           builtin_define ("__STDC_VERSION__=199409L");  \
  57     } while (0)
  58
  59 /* Accept DEC C flags for multithreaded programs.  We use _PTHREAD_USE_D4
  60    instead of PTHREAD_USE_D4 since both have the same effect and the former
  61    doesn't invade the users' namespace.  */
  62
  63 #undef CPP_SPEC
  64 #define CPP_SPEC \
  65 "%{pthread|threads:-D_REENTRANT} %{threads:-D_PTHREAD_USE_D4}"
  66
  67 /* Under OSF4, -p and -pg require -lprof1, and -lprof1 requires -lpdf.  */
  68
  69 #define LIB_SPEC \
  70 "%{p|pg:-lprof1%{pthread|threads:_r} -lpdf} %{a:-lprof2} \
  71  %{threads: -lpthreads} %{pthread|threads: -lpthread -lmach -lexc} -lc"
  72
  73 /* Pass "-G 8" to ld because Alpha's CC does.  Pass -O3 if we are
  74    optimizing, -O1 if we are not.  Pass -S to silence `weak symbol
  75    multiply defined' warnings.  Pass -shared, -non_shared or
  76    -call_shared as appropriate.  Pass -hidden_symbol so that our
  77    constructor and call-frame data structures are not accidentally
  78    overridden.  */
  79 #define LINK_SPEC  \
  80   "-G 8 %{O*:-O3} %{!O*:-O1} -S %{static:-non_shared} \
  81    %{!static:%{shared:-shared -hidden_symbol _GLOBAL_*} \
  82    %{!shared:-call_shared}} %{pg} %{taso} %{rpath*}"
  83
  84 #define STARTFILE_SPEC  \
  85   "%{!shared:%{pg:gcrt0.o%s}%{!pg:%{p:mcrt0.o%s}%{!p:crt0.o%s}}}"
  86
  87 #define ENDFILE_SPEC \
  88   "%{ffast-math|funsafe-math-optimizations:crtfastmath.o%s}"
  89
  90 #define MD_STARTFILE_PREFIX "/usr/lib/cmplrs/cc/"
  91
  92 /* Tru64 UNIX V5.1 requires a special as flag.  Empty by default.  */
  93
  94 #define ASM_OLDAS_SPEC ""
  95
  96 /* In OSF/1 v3.2c, the assembler by default does not output file names which
  97    causes mips-tfile to fail.  Passing -g to the assembler fixes this problem.
  98    ??? Strictly speaking, we need -g only if the user specifies -g.  Passing
  99    it always means that we get slightly larger than necessary object files
 100    if the user does not specify -g.  If we don't pass -g, then mips-tfile
 101    will need to be fixed to work in this case.  Pass -O0 since some
 102    optimization are broken and don't help us anyway.  Pass -nocpp because
 103    there's no point in running CPP on our assembler output.  */
 104 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 105 #define ASM_SPEC "%{malpha-as:-g %(asm_oldas) -nocpp %{pg} -O0}"
 106 #else
 107 #define ASM_SPEC "%{!mgas:-g %(asm_oldas) -nocpp %{pg} -O0}"
 108 #endif
 109
 110 /* Specify to run a post-processor, mips-tfile after the assembler
 111    has run to stuff the ecoff debug information into the object file.
 112    This is needed because the Alpha assembler provides no way
 113    of specifying such information in the assembly file.  */
 114
 115 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 116
 117 #define ASM_FINAL_SPEC "\
 118 %{malpha-as: %{!mno-mips-tfile: \
 119         \n mips-tfile %{v*: -v} \
 120                 %{K: -I %b.o~} \
 121                 %{!K: %{save-temps: -I %b.o~}} \
 122                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 123                 %{,assembler:%i;:%g.s}}}"
 124
 125 #else
 126 #define ASM_FINAL_SPEC "\
 127 %{!mgas: %{!mno-mips-tfile: \
 128         \n mips-tfile %{v*: -v} \
 129                 %{K: -I %b.o~} \
 130                 %{!K: %{save-temps: -I %b.o~}} \
 131                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 132                 %{,assembler:%i;:%g.s}}}"
 133
 134 #endif
 135
 136 #undef EXTRA_SPECS
 137 #define EXTRA_SPECS { "asm_oldas", ASM_OLDAS_SPEC }
 138
 139 /* Indicate that we have a stamp.h to use.  */
 140 #ifndef CROSS_DIRECTORY_STRUCTURE
 141 #define HAVE_STAMP_H 1
 142 #endif
 143
 144 /* Attempt to turn on access permissions for the stack.  */
 145
 146 #define ENABLE_EXECUTE_STACK                                            \
 147 void                                                                    \
 148 __enable_execute_stack (void *addr)                                     \
 149 {                                                                       \
 150   extern int mprotect (const void *, size_t, int);                      \
 151   long size = getpagesize ();                                           \
 152   long mask = ~(size-1);                                                \
 153   char *page = (char *) (((long) addr) & mask);                         \
 154   char *end  = (char *) ((((long) (addr + TRAMPOLINE_SIZE)) & mask) + size); \
 155                                                                         \
 156   /* 7 is PROT_READ | PROT_WRITE | PROT_EXEC */                         \
 157   if (mprotect (page, end - page, 7) < 0)                               \
 158     perror ("mprotect of trampoline code");                             \
 159 }
 160
 161 /* Digital UNIX V4.0E (1091)/usr/include/sys/types.h 4.3.49.9 1997/08/14 */
 162 #define SIZE_TYPE       "long unsigned int"
 163 #define PTRDIFF_TYPE    "long int"
 164
 165 /* The linker will stick __main into the .init section.  */
 166 #define HAS_INIT_SECTION
 167 #define LD_INIT_SWITCH "-init"
 168 #define LD_FINI_SWITCH "-fini"
 169
 170 /* The linker needs a space after "-o".  This allows -oldstyle_liblookup to
 171    be passed to ld.  */
 172 #define SWITCHES_NEED_SPACES "o"
 173
 174 /* Select a format to encode pointers in exception handling data.  CODE
 175    is 0 for data, 1 for code labels, 2 for function pointers.  GLOBAL is
 176    true if the symbol may be affected by dynamic relocations.
 177
 178    We really ought to be using the SREL32 relocations that ECOFF has,
 179    but no version of the native assembler supports creating such things,
 180    and Compaq has no plans to rectify this.  Worse, the dynamic loader
 181    cannot handle unaligned relocations, so we have to make sure that
 182    things get padded appropriately.  */
 183 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)                            \
 184   (TARGET_GAS                                                                \
 185    ? (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4) \
 186    : DW_EH_PE_aligned)
 187
 188 /* This is how we tell the assembler that a symbol is weak.  */
 189
 190 #define ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, VALUE)        \
 191   do                                                    \
 192     {                                                   \
 193       (*targetm.asm_out.globalize_label) (FILE, NAME);  \
 194       fputs ("\t.weakext\t", FILE);                     \
 195       assemble_name (FILE, NAME);                       \
 196       if (VALUE)                                        \
 197         {                                               \
 198           fputc (' ', FILE);                            \
 199           assemble_name (FILE, VALUE);                  \
 200         }                                               \
 201       fputc ('\n', FILE);                               \
 202     }                                                   \
 203   while (0)
 204
 205 #define ASM_WEAKEN_LABEL(FILE, NAME) ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, 0)
 206
 207 /* Handle #pragma weak and #pragma pack.  */
 208 #define HANDLE_SYSV_PRAGMA 1
 209
 210 /* Handle #pragma extern_prefix.  Technically only needed for Tru64 5.x,
 211    but easier to manipulate preprocessor bits from here.  */
 212 #define TARGET_HANDLE_PRAGMA_EXTERN_PREFIX 1