gomp-20050608-branch/gcc/config/pa/som.h

   1 /* Definitions for SOM assembler support.
   2    Copyright (C) 1999, 2001, 2002, 2003, 2004, 2005 Free Software Foundation,
   3    Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public 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 COPYING.  If not, write to
  19 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 /* So we can conditionalize small amounts of code in pa.c or pa.md.  */
  23 #undef TARGET_SOM
  24 #define TARGET_SOM 1
  25
  26 /* We do not use BINCL stabs in SOM.
  27    ??? If it does not hurt, we probably should to avoid useless divergence
  28    from other embedded stabs implementations.  */
  29 #undef DBX_USE_BINCL
  30
  31 #define DBX_LINES_FUNCTION_RELATIVE 1
  32
  33 /* gdb needs a null N_SO at the end of each file for scattered loading.  */
  34
  35 #define DBX_OUTPUT_NULL_N_SO_AT_MAIN_SOURCE_FILE_END
  36
  37 /* HPUX has a program 'chatr' to list the dependencies of dynamically
  38    linked executables and shared libraries.  */
  39 #define LDD_SUFFIX "chatr"
  40 /* Look for lines like "dynamic   /usr/lib/X11R5/libX11.sl"
  41    or "static    /usr/lib/X11R5/libX11.sl".
  42
  43    HPUX 10.20 also has lines like "static branch prediction ..."
  44    so we filter that out explicitly.
  45
  46    We also try to bound our search for libraries with marker
  47    lines.  What a pain.  */
  48 #define PARSE_LDD_OUTPUT(PTR)                                   \
  49 do {                                                            \
  50   static int in_shlib_list = 0;                                 \
  51   while (*PTR == ' ') PTR++;                                    \
  52   if (strncmp (PTR, "shared library list:",                     \
  53                sizeof ("shared library list:") - 1) == 0)       \
  54     {                                                           \
  55       PTR = 0;                                                  \
  56       in_shlib_list = 1;                                        \
  57     }                                                           \
  58   else if (strncmp (PTR, "shared library binding:",             \
  59                     sizeof ("shared library binding:") - 1) == 0)\
  60     {                                                           \
  61       PTR = 0;                                                  \
  62       in_shlib_list = 0;                                        \
  63     }                                                           \
  64   else if (strncmp (PTR, "static branch prediction disabled",   \
  65                     sizeof ("static branch prediction disabled") - 1) == 0)\
  66     {                                                           \
  67       PTR = 0;                                                  \
  68       in_shlib_list = 0;                                        \
  69     }                                                           \
  70   else if (in_shlib_list                                        \
  71            &&  strncmp (PTR, "dynamic", sizeof ("dynamic") - 1) == 0) \
  72     {                                                           \
  73       PTR += sizeof ("dynamic") - 1;                            \
  74       while (*p == ' ') PTR++;                                  \
  75     }                                                           \
  76   else if (in_shlib_list                                        \
  77            && strncmp (PTR, "static", sizeof ("static") - 1) == 0) \
  78     {                                                           \
  79       PTR += sizeof ("static") - 1;                             \
  80       while (*p == ' ') PTR++;                                  \
  81     }                                                           \
  82   else                                                          \
  83     PTR = 0;                                                    \
  84 } while (0)
  85
  86 /* Output the label for a function definition.  */
  87 #ifndef HP_FP_ARG_DESCRIPTOR_REVERSED
  88 #define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)    \
  89   do { fprintf (FILE, ",ARGW%d=FR", (ARG0));            \
  90        fprintf (FILE, ",ARGW%d=FU", (ARG1));} while (0)
  91 #define DFMODE_RETURN_STRING ",RTNVAL=FU"
  92 #define SFMODE_RETURN_STRING ",RTNVAL=FR"
  93 #else
  94 #define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)    \
  95   do { fprintf (FILE, ",ARGW%d=FU", (ARG0));            \
  96        fprintf (FILE, ",ARGW%d=FR", (ARG1));} while (0)
  97 #define DFMODE_RETURN_STRING ",RTNVAL=FR"
  98 #define SFMODE_RETURN_STRING ",RTNVAL=FU"
  99 #endif
 100
 101 \f
 102 #define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
 103     do { tree fntype = TREE_TYPE (TREE_TYPE (DECL));                    \
 104          tree tree_type = TREE_TYPE (DECL);                             \
 105          tree parm;                                                     \
 106          int i;                                                         \
 107          if (TREE_PUBLIC (DECL) || TARGET_GAS)                          \
 108            {                                                            \
 109              if (TREE_PUBLIC (DECL))                                    \
 110                {                                                        \
 111                  fputs ("\t.EXPORT ", FILE);                            \
 112                  assemble_name (FILE, NAME);                            \
 113                  fputs (",ENTRY,PRIV_LEV=3", FILE);                     \
 114                }                                                        \
 115              else                                                       \
 116                {                                                        \
 117                  fputs ("\t.PARAM ", FILE);                             \
 118                  assemble_name (FILE, NAME);                            \
 119                  fputs (",PRIV_LEV=3", FILE);                           \
 120                }                                                        \
 121              for (parm = DECL_ARGUMENTS (DECL), i = 0; parm && i < 4;   \
 122                   parm = TREE_CHAIN (parm))                             \
 123                {                                                        \
 124                  if (TYPE_MODE (DECL_ARG_TYPE (parm)) == SFmode         \
 125                      && ! TARGET_SOFT_FLOAT)                            \
 126                    fprintf (FILE, ",ARGW%d=FR", i++);                   \
 127                  else if (TYPE_MODE (DECL_ARG_TYPE (parm)) == DFmode    \
 128                           && ! TARGET_SOFT_FLOAT)                       \
 129                    {                                                    \
 130                      if (i <= 2)                                        \
 131                        {                                                \
 132                          if (i == 1) i++;                               \
 133                          ASM_DOUBLE_ARG_DESCRIPTORS (FILE, i++, i++);   \
 134                        }                                                \
 135                      else                                               \
 136                        break;                                           \
 137                    }                                                    \
 138                  else                                                   \
 139                    {                                                    \
 140                      int arg_size =                                     \
 141                        FUNCTION_ARG_SIZE (TYPE_MODE (DECL_ARG_TYPE (parm)),\
 142                                           DECL_ARG_TYPE (parm));        \
 143                      /* Passing structs by invisible reference uses     \
 144                         one general register.  */                       \
 145                      if (arg_size > 2                                   \
 146                          || TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))    \
 147                        arg_size = 1;                                    \
 148                      if (arg_size == 2 && i <= 2)                       \
 149                        {                                                \
 150                          if (i == 1) i++;                               \
 151                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 152                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 153                        }                                                \
 154                      else if (arg_size == 1)                            \
 155                        fprintf (FILE, ",ARGW%d=GR", i++);               \
 156                      else                                               \
 157                        i += arg_size;                                   \
 158                    }                                                    \
 159                }                                                        \
 160              /* anonymous args */                                       \
 161              if (TYPE_ARG_TYPES (tree_type) != 0                        \
 162                  && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (tree_type)))\
 163                      != void_type_node))                                \
 164                {                                                        \
 165                  for (; i < 4; i++)                                     \
 166                    fprintf (FILE, ",ARGW%d=GR", i);                     \
 167                }                                                        \
 168              if (TYPE_MODE (fntype) == DFmode && ! TARGET_SOFT_FLOAT)   \
 169                fputs (DFMODE_RETURN_STRING, FILE);                      \
 170              else if (TYPE_MODE (fntype) == SFmode && ! TARGET_SOFT_FLOAT) \
 171                fputs (SFMODE_RETURN_STRING, FILE);                      \
 172              else if (fntype != void_type_node)                         \
 173                fputs (",RTNVAL=GR", FILE);                              \
 174              fputs ("\n", FILE);                                        \
 175            }} while (0)
 176
 177 #define TARGET_ASM_FILE_START pa_som_file_start
 178 #define TARGET_ASM_INIT_SECTIONS pa_som_asm_init_sections
 179
 180 /* String to output before writable data.  */
 181 #define DATA_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $DATA$\n"
 182
 183 /* String to output before uninitialized data.  */
 184 #define BSS_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $BSS$\n"
 185
 186 /* This is how to output a command to make the user-level label
 187    named NAME defined for reference from other files.  We use
 188    assemble_name_raw instead of assemble_name since a symbol in
 189    a .IMPORT directive that isn't otherwise referenced is not
 190    placed in the symbol table of the assembled object.
 191
 192    Failure to import a function reference can cause the HP linker
 193    to segmentation fault!
 194
 195    Note that the SOM based tools need the symbol imported as a
 196    CODE symbol, while the ELF based tools require the symbol to
 197    be imported as an ENTRY symbol.  */
 198
 199 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME) \
 200   pa_hpux_asm_output_external ((FILE), (DECL), (NAME))
 201 #define ASM_OUTPUT_EXTERNAL_REAL(FILE, DECL, NAME) \
 202   do { fputs ("\t.IMPORT ", FILE);                                      \
 203        assemble_name_raw (FILE, NAME);                                  \
 204        if (FUNCTION_NAME_P (NAME))                                      \
 205          fputs (",CODE\n", FILE);                                       \
 206        else                                                             \
 207          fputs (",DATA\n", FILE);                                       \
 208      } while (0)
 209
 210 /* The bogus HP assembler requires ALL external references to be
 211    "imported", even library calls.  They look a bit different, so
 212    here's this macro.
 213
 214    Also note not all libcall names are passed to pa_encode_section_info
 215    (__main for example).  To make sure all libcall names have section
 216    info recorded in them, we do it here.
 217
 218    We must also ensure that a libcall that has been previously
 219    exported is not subsequently imported since the HP assembler may
 220    change the type from an ENTRY to a CODE symbol.  This would make
 221    the symbol local.  We are forced to use the identifier node
 222    associated with the real assembler name for this check as the
 223    symbol_ref available in ASM_DECLARE_FUNCTION_NAME is not the
 224    same as the one used here.  As a result, we can't use flags
 225    in the symbol_ref for this check.  The identifier check assumes
 226    assemble_external_libcall is called before the symbol is used.  */
 227
 228 #define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, RTL) \
 229   do { const char *name;                                                \
 230        tree id;                                                         \
 231                                                                         \
 232        if (!function_label_operand (RTL, VOIDmode))                     \
 233          hppa_encode_label (RTL);                                       \
 234                                                                         \
 235        name = targetm.strip_name_encoding (XSTR ((RTL), 0));            \
 236        id = maybe_get_identifier (name);                                \
 237        if (!id || !TREE_SYMBOL_REFERENCED (id))                         \
 238          {                                                              \
 239            fputs ("\t.IMPORT ", FILE);                                  \
 240            assemble_name_raw (FILE, XSTR ((RTL), 0));                   \
 241            fputs (",CODE\n", FILE);                                     \
 242          }                                                              \
 243      } while (0)
 244
 245 /* We want __gcc_plt_call to appear in every program built by
 246    gcc, so we make a reference to it out of __main.
 247    We use the asm statement to fool the optimizer into not
 248    removing the dead (but important) initialization of
 249    REFERENCE.  */
 250
 251 #define DO_GLOBAL_DTORS_BODY                    \
 252 do {                                            \
 253   extern void __gcc_plt_call (void);            \
 254   void (*reference)(void) = &__gcc_plt_call;    \
 255   func_ptr *p;                                  \
 256   __asm__ ("" : : "r" (reference));             \
 257   for (p = __DTOR_LIST__ + 1; *p; )             \
 258     (*p++) ();                                  \
 259 } while (0)
 260
 261 /* This macro specifies the biggest alignment supported by the object
 262    file format of this machine.
 263
 264    The .align directive in the HP assembler allows alignments up to 4096
 265    bytes.  However, the maximum alignment of a global common symbol is 8
 266    bytes for objects smaller than the page size (4096 bytes).  For larger
 267    objects, the linker provides an alignment of 32 bytes.  Unfortunately,
 268    this macro doesn't provide a mechanism to test for common symbols.  */
 269 #define MAX_OFILE_ALIGNMENT 32768
 270
 271 /* The SOM linker hardcodes paths into binaries.  As a result, dotdots
 272    must be removed from library prefixes to prevent binaries from depending
 273    on the location of the GCC tool directory.  The downside is GCC
 274    cannot be moved after installation using a symlink.  */
 275 #define ALWAYS_STRIP_DOTDOT 1
 276
 277 /* If GAS supports weak, we can support weak when we have working linker
 278    support for secondary definitions and are generating code for GAS.  */
 279 #ifdef HAVE_GAS_WEAK
 280 #define SUPPORTS_WEAK (TARGET_SOM_SDEF && TARGET_GAS)
 281 #else
 282 #define SUPPORTS_WEAK 0
 283 #endif
 284
 285 /* CVS GAS as of 4/28/04 supports a comdat parameter for the .nsubspa
 286    directive.  This provides one-only linkage semantics even though we
 287    don't have weak support.  */
 288 #ifdef HAVE_GAS_NSUBSPA_COMDAT
 289 #define SUPPORTS_SOM_COMDAT (TARGET_GAS)
 290 #else
 291 #define SUPPORTS_SOM_COMDAT 0
 292 #endif
 293
 294 /* We can support one only if we support weak or comdat.  */
 295 #define SUPPORTS_ONE_ONLY (SUPPORTS_WEAK || SUPPORTS_SOM_COMDAT)
 296
 297 /* We use DECL_COMMON for uninitialized one-only variables as we don't
 298    have linkonce .bss.  We use SOM secondary definitions or comdat for
 299    initialized variables and functions.  */
 300 #define MAKE_DECL_ONE_ONLY(DECL) \
 301   do {                                                                  \
 302     if (TREE_CODE (DECL) == VAR_DECL                                    \
 303         && (DECL_INITIAL (DECL) == 0                                    \
 304             || DECL_INITIAL (DECL) == error_mark_node))                 \
 305       DECL_COMMON (DECL) = 1;                                           \
 306     else if (SUPPORTS_WEAK)                                             \
 307       DECL_WEAK (DECL) = 1;                                             \
 308   } while (0)
 309
 310 /* This is how we tell the assembler that a symbol is weak.  The SOM
 311    weak implementation uses the secondary definition (sdef) flag.
 312
 313    The behavior of sdef symbols is similar to ELF weak symbols in that
 314    multiple definitions can occur without incurring a link error.
 315    However, they differ in the following ways:
 316      1) Undefined sdef symbols are not allowed.
 317      2) The linker searches for undefined sdef symbols and will load an
 318         archive library member to resolve an undefined sdef symbol.
 319      3) The exported symbol from a shared library is a primary symbol
 320         rather than a sdef symbol.  Thus, more care is needed in the
 321         ordering of libraries.
 322
 323    It appears that the linker discards extra copies of "weak" functions
 324    when linking shared libraries, independent of whether or not they
 325    are in their own section.  In linking final executables, -Wl,-O can
 326    be used to remove dead procedures.  Thus, support for named sections
 327    is not needed and in previous testing caused problems with various
 328    HP tools.  */
 329 #define ASM_WEAKEN_LABEL(FILE,NAME) \
 330   do { fputs ("\t.weak\t", FILE);                               \
 331        assemble_name (FILE, NAME);                              \
 332        fputc ('\n', FILE);                                      \
 333        targetm.asm_out.globalize_label (FILE, NAME);            \
 334   } while (0)
 335
 336 /* We can't handle weak aliases, and therefore can't support pragma weak.
 337    Suppress the use of pragma weak in gthr-dce.h and gthr-posix.h.  */
 338 #define GTHREAD_USE_WEAK 0