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 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, 51 Franklin Street, Fifth Floor,
  21 Boston, MA 02110-1301, 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_assert ("system=unix");                 \
  45         builtin_assert ("system=xpg4");                 \
  46         /* Tru64 UNIX V5 has a 16 byte long             \
  47            double type and requires __X_FLOAT           \
  48            to be defined for <math.h>.  */              \
  49         if (LONG_DOUBLE_TYPE_SIZE == 128)               \
  50           builtin_define ("__X_FLOAT");                 \
  51                                                         \
  52         /* Tru64 UNIX V4/V5 provide several ISO C94     \
  53            features protected by the corresponding      \
  54            __STDC_VERSION__ macro.  libstdc++ v3        \
  55            needs them as well.  */                      \
  56         if (c_dialect_cxx ())                           \
  57           builtin_define ("__STDC_VERSION__=199409L");  \
  58     } while (0)
  59
  60 /* Accept DEC C flags for multithreaded programs.  We use _PTHREAD_USE_D4
  61    instead of PTHREAD_USE_D4 since both have the same effect and the former
  62    doesn't invade the users' namespace.  */
  63
  64 #undef CPP_SUBTARGET_SPEC
  65 #define CPP_SUBTARGET_SPEC \
  66 "%{pthread|threads:-D_REENTRANT} %{threads:-D_PTHREAD_USE_D4}"
  67
  68 /* Under OSF4, -p and -pg require -lprof1, and -lprof1 requires -lpdf.  */
  69
  70 #define LIB_SPEC \
  71 "%{p|pg:-lprof1%{pthread|threads:_r} -lpdf} %{a:-lprof2} \
  72  %{threads: -lpthreads} %{pthread|threads: -lpthread -lmach -lexc} -lc"
  73
  74 /* Pass "-G 8" to ld because Alpha's CC does.  Pass -O3 if we are
  75    optimizing, -O1 if we are not.  Pass -S to silence `weak symbol
  76    multiply defined' warnings.  Pass -shared, -non_shared or
  77    -call_shared as appropriate.  Pass -hidden_symbol so that our
  78    constructor and call-frame data structures are not accidentally
  79    overridden.  */
  80 #define LINK_SPEC  \
  81   "-G 8 %{O*:-O3} %{!O*:-O1} -S %{static:-non_shared} \
  82    %{!static:%{shared:-shared -hidden_symbol _GLOBAL_*} \
  83    %{!shared:-call_shared}} %{pg} %{taso} %{rpath*}"
  84
  85 #define STARTFILE_SPEC  \
  86   "%{!shared:%{pg:gcrt0.o%s}%{!pg:%{p:mcrt0.o%s}%{!p:crt0.o%s}}}"
  87
  88 #define ENDFILE_SPEC \
  89   "%{ffast-math|funsafe-math-optimizations:crtfastmath.o%s}"
  90
  91 #define MD_STARTFILE_PREFIX "/usr/lib/cmplrs/cc/"
  92
  93 /* Tru64 UNIX V5.1 requires a special as flag.  Empty by default.  */
  94
  95 #define ASM_OLDAS_SPEC ""
  96
  97 /* In OSF/1 v3.2c, the assembler by default does not output file names which
  98    causes mips-tfile to fail.  Passing -g to the assembler fixes this problem.
  99    ??? Strictly speaking, we need -g only if the user specifies -g.  Passing
 100    it always means that we get slightly larger than necessary object files
 101    if the user does not specify -g.  If we don't pass -g, then mips-tfile
 102    will need to be fixed to work in this case.  Pass -O0 since some
 103    optimization are broken and don't help us anyway.  Pass -nocpp because
 104    there's no point in running CPP on our assembler output.  */
 105 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 106 #define ASM_SPEC "%{malpha-as:-g %(asm_oldas) -nocpp %{pg} -O0}"
 107 #else
 108 #define ASM_SPEC "%{!mgas:-g %(asm_oldas) -nocpp %{pg} -O0}"
 109 #endif
 110
 111 /* Specify to run a post-processor, mips-tfile after the assembler
 112    has run to stuff the ecoff debug information into the object file.
 113    This is needed because the Alpha assembler provides no way
 114    of specifying such information in the assembly file.  */
 115
 116 #if ((TARGET_DEFAULT | TARGET_CPU_DEFAULT) & MASK_GAS) != 0
 117
 118 #define ASM_FINAL_SPEC "\
 119 %{malpha-as: %{!mno-mips-tfile: \
 120         \n mips-tfile %{v*: -v} \
 121                 %{K: -I %b.o~} \
 122                 %{!K: %{save-temps: -I %b.o~}} \
 123                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 124                 %{.s:%i} %{!.s:%g.s}}}"
 125
 126 #else
 127 #define ASM_FINAL_SPEC "\
 128 %{!mgas: %{!mno-mips-tfile: \
 129         \n mips-tfile %{v*: -v} \
 130                 %{K: -I %b.o~} \
 131                 %{!K: %{save-temps: -I %b.o~}} \
 132                 %{c:%W{o*}%{!o*:-o %b.o}}%{!c:-o %U.o} \
 133                 %{.s:%i} %{!.s:%g.s}}}"
 134
 135 #endif
 136
 137 #undef SUBTARGET_EXTRA_SPECS
 138 #define SUBTARGET_EXTRA_SPECS { "asm_oldas", ASM_OLDAS_SPEC }
 139
 140 /* Indicate that we have a stamp.h to use.  */
 141 #ifndef CROSS_COMPILE
 142 #define HAVE_STAMP_H 1
 143 #endif
 144
 145 /* Attempt to turn on access permissions for the stack.  */
 146
 147 #define ENABLE_EXECUTE_STACK                                            \
 148 void                                                                    \
 149 __enable_execute_stack (void *addr)                                     \
 150 {                                                                       \
 151   extern int mprotect (const void *, size_t, int);                      \
 152   long size = getpagesize ();                                           \
 153   long mask = ~(size-1);                                                \
 154   char *page = (char *) (((long) addr) & mask);                         \
 155   char *end  = (char *) ((((long) (addr + TRAMPOLINE_SIZE)) & mask) + size); \
 156                                                                         \
 157   /* 7 is PROT_READ | PROT_WRITE | PROT_EXEC */                         \
 158   if (mprotect (page, end - page, 7) < 0)                               \
 159     perror ("mprotect of trampoline code");                             \
 160 }
 161
 162 /* Digital UNIX V4.0E (1091)/usr/include/sys/types.h 4.3.49.9 1997/08/14 */
 163 #define SIZE_TYPE       "long unsigned int"
 164 #define PTRDIFF_TYPE    "long int"
 165
 166 /* The linker will stick __main into the .init section.  */
 167 #define HAS_INIT_SECTION
 168 #define LD_INIT_SWITCH "-init"
 169 #define LD_FINI_SWITCH "-fini"
 170
 171 /* The linker needs a space after "-o".  This allows -oldstyle_liblookup to
 172    be passed to ld.  */
 173 #define SWITCHES_NEED_SPACES "o"
 174
 175 /* Select a format to encode pointers in exception handling data.  CODE
 176    is 0 for data, 1 for code labels, 2 for function pointers.  GLOBAL is
 177    true if the symbol may be affected by dynamic relocations.
 178
 179    We really ought to be using the SREL32 relocations that ECOFF has,
 180    but no version of the native assembler supports creating such things,
 181    and Compaq has no plans to rectify this.  Worse, the dynamic loader
 182    cannot handle unaligned relocations, so we have to make sure that
 183    things get padded appropriately.  */
 184 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)                            \
 185   (TARGET_GAS                                                                \
 186    ? (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4) \
 187    : DW_EH_PE_aligned)
 188
 189 /* This is how we tell the assembler that a symbol is weak.  */
 190
 191 #define ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, VALUE)        \
 192   do                                                    \
 193     {                                                   \
 194       (*targetm.asm_out.globalize_label) (FILE, NAME);  \
 195       fputs ("\t.weakext\t", FILE);                     \
 196       assemble_name (FILE, NAME);                       \
 197       if (VALUE)                                        \
 198         {                                               \
 199           fputc (' ', FILE);                            \
 200           assemble_name (FILE, VALUE);                  \
 201         }                                               \
 202       fputc ('\n', FILE);                               \
 203     }                                                   \
 204   while (0)
 205
 206 #define ASM_WEAKEN_LABEL(FILE, NAME) ASM_OUTPUT_WEAK_ALIAS(FILE, NAME, 0)
 207
 208 /* Handle #pragma weak and #pragma pack.  */
 209 #define HANDLE_SYSV_PRAGMA 1
 210
 211 /* Handle #pragma extern_prefix.  Technically only needed for Tru64 5.x,
 212    but easier to manipulate preprocessor bits from here.  */
 213 #define TARGET_HANDLE_PRAGMA_EXTERN_PREFIX 1