gcc/config/pa/som.h

   1 /* Definitions for SOM assembler support.
   2    Copyright (C) 1999-2018 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 3, or (at your option)
   9 any later version.
  10
  11 GCC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* So we can conditionalize small amounts of code in pa.c or pa.md.  */
  21 #undef TARGET_SOM
  22 #define TARGET_SOM 1
  23
  24 /* We do not use BINCL stabs in SOM.
  25    ??? If it does not hurt, we probably should to avoid useless divergence
  26    from other embedded stabs implementations.  */
  27 #undef DBX_USE_BINCL
  28
  29 #define DBX_LINES_FUNCTION_RELATIVE 1
  30
  31 /* gdb needs a null N_SO at the end of each file for scattered loading.  */
  32
  33 #define DBX_OUTPUT_NULL_N_SO_AT_MAIN_SOURCE_FILE_END
  34
  35 /* HPUX has a program 'chatr' to list the dependencies of dynamically
  36    linked executables and shared libraries.  */
  37 #define LDD_SUFFIX "chatr"
  38 /* Look for lines like "dynamic   /usr/lib/X11R5/libX11.sl"
  39    or "static    /usr/lib/X11R5/libX11.sl".
  40
  41    HPUX 10.20 also has lines like "static branch prediction ..."
  42    so we filter that out explicitly.
  43
  44    We also try to bound our search for libraries with marker
  45    lines.  What a pain.  */
  46 #define PARSE_LDD_OUTPUT(PTR)                                   \
  47 do {                                                            \
  48   static int in_shlib_list = 0;                                 \
  49   while (*PTR == ' ') PTR++;                                    \
  50   if (strncmp (PTR, "shared library list:",                     \
  51                sizeof ("shared library list:") - 1) == 0)       \
  52     {                                                           \
  53       PTR = 0;                                                  \
  54       in_shlib_list = 1;                                        \
  55     }                                                           \
  56   else if (strncmp (PTR, "shared library binding:",             \
  57                     sizeof ("shared library binding:") - 1) == 0)\
  58     {                                                           \
  59       PTR = 0;                                                  \
  60       in_shlib_list = 0;                                        \
  61     }                                                           \
  62   else if (strncmp (PTR, "static branch prediction disabled",   \
  63                     sizeof ("static branch prediction disabled") - 1) == 0)\
  64     {                                                           \
  65       PTR = 0;                                                  \
  66       in_shlib_list = 0;                                        \
  67     }                                                           \
  68   else if (in_shlib_list                                        \
  69            &&  strncmp (PTR, "dynamic", sizeof ("dynamic") - 1) == 0) \
  70     {                                                           \
  71       PTR += sizeof ("dynamic") - 1;                            \
  72       while (*p == ' ') PTR++;                                  \
  73     }                                                           \
  74   else if (in_shlib_list                                        \
  75            && strncmp (PTR, "static", sizeof ("static") - 1) == 0) \
  76     {                                                           \
  77       PTR += sizeof ("static") - 1;                             \
  78       while (*p == ' ') PTR++;                                  \
  79     }                                                           \
  80   else                                                          \
  81     PTR = 0;                                                    \
  82 } while (0)
  83
  84 /* Output the label for a function definition.  */
  85 #ifndef HP_FP_ARG_DESCRIPTOR_REVERSED
  86 #define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)    \
  87   do { fprintf (FILE, ",ARGW%d=FR", (ARG0));            \
  88        fprintf (FILE, ",ARGW%d=FU", (ARG1));} while (0)
  89 #define DFMODE_RETURN_STRING ",RTNVAL=FU"
  90 #define SFMODE_RETURN_STRING ",RTNVAL=FR"
  91 #else
  92 #define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)    \
  93   do { fprintf (FILE, ",ARGW%d=FU", (ARG0));            \
  94        fprintf (FILE, ",ARGW%d=FR", (ARG1));} while (0)
  95 #define DFMODE_RETURN_STRING ",RTNVAL=FR"
  96 #define SFMODE_RETURN_STRING ",RTNVAL=FU"
  97 #endif
  98
  99 \f
 100 #define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
 101     do { tree fntype = TREE_TYPE (TREE_TYPE (DECL));                    \
 102          tree tree_type = TREE_TYPE (DECL);                             \
 103          tree parm;                                                     \
 104          int i;                                                         \
 105          if (TREE_PUBLIC (DECL) || TARGET_GAS)                          \
 106            {                                                            \
 107              if (TREE_PUBLIC (DECL))                                    \
 108                {                                                        \
 109                  fputs ("\t.EXPORT ", FILE);                            \
 110                  assemble_name (FILE, NAME);                            \
 111                  fputs (",ENTRY,PRIV_LEV=3", FILE);                     \
 112                }                                                        \
 113              else                                                       \
 114                {                                                        \
 115                  fputs ("\t.PARAM ", FILE);                             \
 116                  assemble_name (FILE, NAME);                            \
 117                  fputs (",PRIV_LEV=3", FILE);                           \
 118                }                                                        \
 119              for (parm = DECL_ARGUMENTS (DECL), i = 0; parm && i < 4;   \
 120                   parm = DECL_CHAIN (parm))                             \
 121                {                                                        \
 122                  if (TYPE_MODE (DECL_ARG_TYPE (parm)) == SFmode         \
 123                      && ! TARGET_SOFT_FLOAT)                            \
 124                    fprintf (FILE, ",ARGW%d=FR", i++);                   \
 125                  else if (TYPE_MODE (DECL_ARG_TYPE (parm)) == DFmode    \
 126                           && ! TARGET_SOFT_FLOAT)                       \
 127                    {                                                    \
 128                      if (i <= 2)                                        \
 129                        {                                                \
 130                          if (i == 1) i++;                               \
 131                          ASM_DOUBLE_ARG_DESCRIPTORS (FILE, i++, i++);   \
 132                        }                                                \
 133                      else                                               \
 134                        break;                                           \
 135                    }                                                    \
 136                  else                                                   \
 137                    {                                                    \
 138                      int arg_size =                                     \
 139                        pa_function_arg_size (TYPE_MODE (DECL_ARG_TYPE (parm)),\
 140                                              DECL_ARG_TYPE (parm));     \
 141                      /* Passing structs by invisible reference uses     \
 142                         one general register.  */                       \
 143                      if (arg_size > 2                                   \
 144                          || TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))    \
 145                        arg_size = 1;                                    \
 146                      if (arg_size == 2 && i <= 2)                       \
 147                        {                                                \
 148                          if (i == 1) i++;                               \
 149                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 150                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 151                        }                                                \
 152                      else if (arg_size == 1)                            \
 153                        fprintf (FILE, ",ARGW%d=GR", i++);               \
 154                      else                                               \
 155                        i += arg_size;                                   \
 156                    }                                                    \
 157                }                                                        \
 158              /* anonymous args */                                       \
 159              if (stdarg_p (tree_type))                                  \
 160                {                                                        \
 161                  for (; i < 4; i++)                                     \
 162                    fprintf (FILE, ",ARGW%d=GR", i);                     \
 163                }                                                        \
 164              if (TYPE_MODE (fntype) == DFmode && ! TARGET_SOFT_FLOAT)   \
 165                fputs (DFMODE_RETURN_STRING, FILE);                      \
 166              else if (TYPE_MODE (fntype) == SFmode && ! TARGET_SOFT_FLOAT) \
 167                fputs (SFMODE_RETURN_STRING, FILE);                      \
 168              else if (fntype != void_type_node)                         \
 169                fputs (",RTNVAL=GR", FILE);                              \
 170              fputs ("\n", FILE);                                        \
 171            }} while (0)
 172
 173 #define TARGET_ASM_FILE_START pa_som_file_start
 174 #define TARGET_ASM_INIT_SECTIONS pa_som_asm_init_sections
 175
 176 /* String to output before writable data.  */
 177 #define DATA_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $DATA$\n"
 178
 179 /* String to output before uninitialized data.  */
 180 #define BSS_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $BSS$\n"
 181
 182 /* This is how to output a command to make the user-level label
 183    named NAME defined for reference from other files.  We use
 184    assemble_name_raw instead of assemble_name since a symbol in
 185    a .IMPORT directive that isn't otherwise referenced is not
 186    placed in the symbol table of the assembled object.
 187
 188    Failure to import a function reference can cause the HP linker
 189    to segmentation fault!
 190
 191    Note that the SOM based tools need the symbol imported as a
 192    CODE symbol, while the ELF based tools require the symbol to
 193    be imported as an ENTRY symbol.  */
 194
 195 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME) \
 196   pa_hpux_asm_output_external ((FILE), (DECL), (NAME))
 197 #define ASM_OUTPUT_EXTERNAL_REAL(FILE, DECL, NAME) \
 198   do { fputs ("\t.IMPORT ", FILE);                                      \
 199        assemble_name_raw (FILE, NAME);                                  \
 200        if (FUNCTION_NAME_P (NAME))                                      \
 201          fputs (",CODE\n", FILE);                                       \
 202        else                                                             \
 203          fputs (",DATA\n", FILE);                                       \
 204      } while (0)
 205
 206 /* The bogus HP assembler requires ALL external references to be
 207    "imported", even library calls.  They look a bit different, so
 208    here's this macro.
 209
 210    Also note not all libcall names are passed to pa_encode_section_info
 211    (__main for example).  To make sure all libcall names have section
 212    info recorded in them, we do it here.
 213
 214    We must also ensure that a libcall that has been previously
 215    exported is not subsequently imported since the HP assembler may
 216    change the type from an ENTRY to a CODE symbol.  This would make
 217    the symbol local.  We are forced to use the identifier node
 218    associated with the real assembler name for this check as the
 219    symbol_ref available in ASM_DECLARE_FUNCTION_NAME is not the
 220    same as the one used here.  As a result, we can't use flags
 221    in the symbol_ref for this check.  The identifier check assumes
 222    assemble_external_libcall is called before the symbol is used.  */
 223
 224 #define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, RTL) \
 225   do { const char *name;                                                \
 226        tree id;                                                         \
 227                                                                         \
 228        if (!function_label_operand (RTL, VOIDmode))                     \
 229          pa_encode_label (RTL);                                         \
 230                                                                         \
 231        name = targetm.strip_name_encoding (XSTR ((RTL), 0));            \
 232        id = maybe_get_identifier (name);                                \
 233        if (!id || !TREE_SYMBOL_REFERENCED (id))                         \
 234          {                                                              \
 235            fputs ("\t.IMPORT ", FILE);                                  \
 236            assemble_name_raw (FILE, XSTR ((RTL), 0));                   \
 237            fputs (",CODE\n", FILE);                                     \
 238          }                                                              \
 239      } while (0)
 240
 241 /* We want __gcc_plt_call to appear in every program built by
 242    gcc, so we make a reference to it out of __main.
 243    We use the asm statement to fool the optimizer into not
 244    removing the dead (but important) initialization of
 245    REFERENCE.  */
 246
 247 #define DO_GLOBAL_DTORS_BODY                    \
 248 do {                                            \
 249   extern void __gcc_plt_call (void);            \
 250   void (*reference)(void) = &__gcc_plt_call;    \
 251   func_ptr *p;                                  \
 252   __asm__ ("" : : "r" (reference));             \
 253   for (p = __DTOR_LIST__ + 1; *p; )             \
 254     (*p++) ();                                  \
 255 } while (0)
 256
 257 /* This macro specifies the biggest alignment supported by the object
 258    file format of this machine.
 259
 260    The .align directive in the HP assembler allows alignments up to 4096
 261    bytes.  However, the maximum alignment of a global common symbol is 8
 262    bytes for objects smaller than the page size (4096 bytes).  For larger
 263    objects, the linker provides an alignment of 32 bytes.  Unfortunately,
 264    this macro doesn't provide a mechanism to test for common symbols.  */
 265 #define MAX_OFILE_ALIGNMENT 32768
 266
 267 /* The SOM linker hardcodes paths into binaries.  As a result, dotdots
 268    must be removed from library prefixes to prevent binaries from depending
 269    on the location of the GCC tool directory.  The downside is GCC
 270    cannot be moved after installation using a symlink.  */
 271 #undef TARGET_ALWAYS_STRIP_DOTDOT
 272 #define TARGET_ALWAYS_STRIP_DOTDOT true
 273
 274 /* If GAS supports weak, we can support weak when we have working linker
 275    support for secondary definitions and are generating code for GAS.
 276    This is primarily for one-only support as SOM doesn't allow undefined
 277    weak symbols.  */
 278 #ifdef HAVE_GAS_WEAK
 279 #define TARGET_SUPPORTS_WEAK (TARGET_SOM_SDEF && TARGET_GAS)
 280 #else
 281 #define TARGET_SUPPORTS_WEAK 0
 282 #endif
 283
 284 /* CVS GAS as of 4/28/04 supports a comdat parameter for the .nsubspa
 285    directive.  This provides one-only linkage semantics even though we
 286    don't have weak support.  */
 287 #ifdef HAVE_GAS_NSUBSPA_COMDAT
 288 #define SUPPORTS_SOM_COMDAT (TARGET_GAS)
 289 #else
 290 #define SUPPORTS_SOM_COMDAT 0
 291 #endif
 292
 293 /* We can support one only if we support weak or comdat.  */
 294 #define SUPPORTS_ONE_ONLY (TARGET_SUPPORTS_WEAK || SUPPORTS_SOM_COMDAT)
 295
 296 /* We use DECL_COMMON for uninitialized one-only variables as we don't
 297    have linkonce .bss.  We use SOM secondary definitions or comdat for
 298    initialized variables and functions.  */
 299 #define MAKE_DECL_ONE_ONLY(DECL) \
 300   do {                                                                  \
 301     if (TREE_CODE (DECL) == VAR_DECL                                    \
 302         && (DECL_INITIAL (DECL) == 0                                    \
 303             || DECL_INITIAL (DECL) == error_mark_node))                 \
 304       DECL_COMMON (DECL) = 1;                                           \
 305     else if (TARGET_SUPPORTS_WEAK)                                      \
 306       DECL_WEAK (DECL) = 1;                                             \
 307   } while (0)
 308
 309 /* This is how we tell the assembler that a symbol is weak.  The SOM
 310    weak implementation uses the secondary definition (sdef) flag.
 311
 312    The behavior of sdef symbols is similar to ELF weak symbols in that
 313    multiple definitions can occur without incurring a link error.
 314    However, they differ in the following ways:
 315      1) Undefined sdef symbols are not allowed.
 316      2) The linker searches for undefined sdef symbols and will load an
 317         archive library member to resolve an undefined sdef symbol.
 318      3) The exported symbol from a shared library is a primary symbol
 319         rather than a sdef symbol.  Thus, more care is needed in the
 320         ordering of libraries.
 321
 322    It appears that the linker discards extra copies of "weak" functions
 323    when linking shared libraries, independent of whether or not they
 324    are in their own section.  In linking final executables, -Wl,-O can
 325    be used to remove dead procedures.  Thus, support for named sections
 326    is not needed and in previous testing caused problems with various
 327    HP tools.  */
 328 #define ASM_WEAKEN_LABEL(FILE,NAME) \
 329   do { fputs ("\t.weak\t", FILE);                               \
 330        assemble_name (FILE, NAME);                              \
 331        fputc ('\n', FILE);                                      \
 332        targetm.asm_out.globalize_label (FILE, NAME);            \
 333   } while (0)
 334
 335 /* We can't handle weak aliases, and therefore can't support pragma weak.
 336    Suppress the use of pragma weak in gthr-dce.h and gthr-posix.h.  */
 337 #define GTHREAD_USE_WEAK 0
 338
 339 /* Shared library suffix.  Collect2 strips the version string after
 340    this suffix when generating constructor/destructor names.  */
 341 #define SHLIB_SUFFIX ".sl"
 342
 343 /* We don't have named sections.  */
 344 #define TARGET_HAVE_NAMED_SECTIONS false
 345
 346 #define TARGET_ASM_TM_CLONE_TABLE_SECTION pa_som_tm_clone_table_section
 347
 348 /* Generate specially named labels to identify DWARF 2 frame unwind
 349    information.  */
 350 #define EH_FRAME_THROUGH_COLLECT2