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                  tree type = DECL_ARG_TYPE (parm);                      \
 123                  machine_mode mode = TYPE_MODE (type);                  \
 124                  if (mode == SFmode && ! TARGET_SOFT_FLOAT)             \
 125                    fprintf (FILE, ",ARGW%d=FR", i++);                   \
 126                  else if (mode == DFmode && ! 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 = pa_function_arg_size (mode, type);  \
 139                      /* Passing structs by invisible reference uses     \
 140                         one general register.  */                       \
 141                      if (arg_size > 2 || TREE_ADDRESSABLE (type))       \
 142                        arg_size = 1;                                    \
 143                      if (arg_size == 2 && i <= 2)                       \
 144                        {                                                \
 145                          if (i == 1) i++;                               \
 146                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 147                          fprintf (FILE, ",ARGW%d=GR", i++);             \
 148                        }                                                \
 149                      else if (arg_size == 1)                            \
 150                        fprintf (FILE, ",ARGW%d=GR", i++);               \
 151                      else                                               \
 152                        i += arg_size;                                   \
 153                    }                                                    \
 154                }                                                        \
 155              /* anonymous args */                                       \
 156              if (stdarg_p (tree_type))                                  \
 157                {                                                        \
 158                  for (; i < 4; i++)                                     \
 159                    fprintf (FILE, ",ARGW%d=GR", i);                     \
 160                }                                                        \
 161              if (TYPE_MODE (fntype) == DFmode && ! TARGET_SOFT_FLOAT)   \
 162                fputs (DFMODE_RETURN_STRING, FILE);                      \
 163              else if (TYPE_MODE (fntype) == SFmode && ! TARGET_SOFT_FLOAT) \
 164                fputs (SFMODE_RETURN_STRING, FILE);                      \
 165              else if (fntype != void_type_node)                         \
 166                fputs (",RTNVAL=GR", FILE);                              \
 167              fputs ("\n", FILE);                                        \
 168            }} while (0)
 169
 170 #define TARGET_ASM_FILE_START pa_som_file_start
 171 #define TARGET_ASM_INIT_SECTIONS pa_som_asm_init_sections
 172
 173 /* String to output before writable data.  */
 174 #define DATA_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $DATA$\n"
 175
 176 /* String to output before uninitialized data.  */
 177 #define BSS_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $BSS$\n"
 178
 179 /* This is how to output a command to make the user-level label
 180    named NAME defined for reference from other files.  We use
 181    assemble_name_raw instead of assemble_name since a symbol in
 182    a .IMPORT directive that isn't otherwise referenced is not
 183    placed in the symbol table of the assembled object.
 184
 185    Failure to import a function reference can cause the HP linker
 186    to segmentation fault!
 187
 188    Note that the SOM based tools need the symbol imported as a
 189    CODE symbol, while the ELF based tools require the symbol to
 190    be imported as an ENTRY symbol.  */
 191
 192 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME) \
 193   pa_hpux_asm_output_external ((FILE), (DECL), (NAME))
 194 #define ASM_OUTPUT_EXTERNAL_REAL(FILE, DECL, NAME) \
 195   do { fputs ("\t.IMPORT ", FILE);                                      \
 196        assemble_name_raw (FILE, NAME);                                  \
 197        if (FUNCTION_NAME_P (NAME))                                      \
 198          fputs (",CODE\n", FILE);                                       \
 199        else                                                             \
 200          fputs (",DATA\n", FILE);                                       \
 201      } while (0)
 202
 203 /* The bogus HP assembler requires ALL external references to be
 204    "imported", even library calls.  They look a bit different, so
 205    here's this macro.
 206
 207    Also note not all libcall names are passed to pa_encode_section_info
 208    (__main for example).  To make sure all libcall names have section
 209    info recorded in them, we do it here.
 210
 211    We must also ensure that a libcall that has been previously
 212    exported is not subsequently imported since the HP assembler may
 213    change the type from an ENTRY to a CODE symbol.  This would make
 214    the symbol local.  We are forced to use the identifier node
 215    associated with the real assembler name for this check as the
 216    symbol_ref available in ASM_DECLARE_FUNCTION_NAME is not the
 217    same as the one used here.  As a result, we can't use flags
 218    in the symbol_ref for this check.  The identifier check assumes
 219    assemble_external_libcall is called before the symbol is used.  */
 220
 221 #define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, RTL) \
 222   do { const char *name;                                                \
 223        tree id;                                                         \
 224                                                                         \
 225        if (!function_label_operand (RTL, VOIDmode))                     \
 226          pa_encode_label (RTL);                                         \
 227                                                                         \
 228        name = targetm.strip_name_encoding (XSTR ((RTL), 0));            \
 229        id = maybe_get_identifier (name);                                \
 230        if (!id || !TREE_SYMBOL_REFERENCED (id))                         \
 231          {                                                              \
 232            fputs ("\t.IMPORT ", FILE);                                  \
 233            assemble_name_raw (FILE, XSTR ((RTL), 0));                   \
 234            fputs (",CODE\n", FILE);                                     \
 235          }                                                              \
 236      } while (0)
 237
 238 /* We want __gcc_plt_call to appear in every program built by
 239    gcc, so we make a reference to it out of __main.
 240    We use the asm statement to fool the optimizer into not
 241    removing the dead (but important) initialization of
 242    REFERENCE.  */
 243
 244 #define DO_GLOBAL_DTORS_BODY                    \
 245 do {                                            \
 246   extern void __gcc_plt_call (void);            \
 247   void (*reference)(void) = &__gcc_plt_call;    \
 248   func_ptr *p;                                  \
 249   __asm__ ("" : : "r" (reference));             \
 250   for (p = __DTOR_LIST__ + 1; *p; )             \
 251     (*p++) ();                                  \
 252 } while (0)
 253
 254 /* This macro specifies the biggest alignment supported by the object
 255    file format of this machine.
 256
 257    The .align directive in the HP assembler allows alignments up to 4096
 258    bytes.  However, the maximum alignment of a global common symbol is 8
 259    bytes for objects smaller than the page size (4096 bytes).  For larger
 260    objects, the linker provides an alignment of 32 bytes.  Unfortunately,
 261    this macro doesn't provide a mechanism to test for common symbols.  */
 262 #define MAX_OFILE_ALIGNMENT 32768
 263
 264 /* The SOM linker hardcodes paths into binaries.  As a result, dotdots
 265    must be removed from library prefixes to prevent binaries from depending
 266    on the location of the GCC tool directory.  The downside is GCC
 267    cannot be moved after installation using a symlink.  */
 268 #undef TARGET_ALWAYS_STRIP_DOTDOT
 269 #define TARGET_ALWAYS_STRIP_DOTDOT true
 270
 271 /* If GAS supports weak, we can support weak when we have working linker
 272    support for secondary definitions and are generating code for GAS.
 273    This is primarily for one-only support as SOM doesn't allow undefined
 274    weak symbols.  */
 275 #ifdef HAVE_GAS_WEAK
 276 #define TARGET_SUPPORTS_WEAK (TARGET_SOM_SDEF && TARGET_GAS)
 277 #else
 278 #define TARGET_SUPPORTS_WEAK 0
 279 #endif
 280
 281 /* CVS GAS as of 4/28/04 supports a comdat parameter for the .nsubspa
 282    directive.  This provides one-only linkage semantics even though we
 283    don't have weak support.  */
 284 #ifdef HAVE_GAS_NSUBSPA_COMDAT
 285 #define SUPPORTS_SOM_COMDAT (TARGET_GAS)
 286 #else
 287 #define SUPPORTS_SOM_COMDAT 0
 288 #endif
 289
 290 /* We can support one only if we support weak or comdat.  */
 291 #define SUPPORTS_ONE_ONLY (TARGET_SUPPORTS_WEAK || SUPPORTS_SOM_COMDAT)
 292
 293 /* We use DECL_COMMON for uninitialized one-only variables as we don't
 294    have linkonce .bss.  We use SOM secondary definitions or comdat for
 295    initialized variables and functions.  */
 296 #define MAKE_DECL_ONE_ONLY(DECL) \
 297   do {                                                                  \
 298     if (TREE_CODE (DECL) == VAR_DECL                                    \
 299         && (DECL_INITIAL (DECL) == 0                                    \
 300             || DECL_INITIAL (DECL) == error_mark_node))                 \
 301       DECL_COMMON (DECL) = 1;                                           \
 302     else if (TARGET_SUPPORTS_WEAK)                                      \
 303       DECL_WEAK (DECL) = 1;                                             \
 304   } while (0)
 305
 306 /* This is how we tell the assembler that a symbol is weak.  The SOM
 307    weak implementation uses the secondary definition (sdef) flag.
 308
 309    The behavior of sdef symbols is similar to ELF weak symbols in that
 310    multiple definitions can occur without incurring a link error.
 311    However, they differ in the following ways:
 312      1) Undefined sdef symbols are not allowed.
 313      2) The linker searches for undefined sdef symbols and will load an
 314         archive library member to resolve an undefined sdef symbol.
 315      3) The exported symbol from a shared library is a primary symbol
 316         rather than a sdef symbol.  Thus, more care is needed in the
 317         ordering of libraries.
 318
 319    It appears that the linker discards extra copies of "weak" functions
 320    when linking shared libraries, independent of whether or not they
 321    are in their own section.  In linking final executables, -Wl,-O can
 322    be used to remove dead procedures.  Thus, support for named sections
 323    is not needed and in previous testing caused problems with various
 324    HP tools.  */
 325 #define ASM_WEAKEN_LABEL(FILE,NAME) \
 326   do { fputs ("\t.weak\t", FILE);                               \
 327        assemble_name (FILE, NAME);                              \
 328        fputc ('\n', FILE);                                      \
 329        targetm.asm_out.globalize_label (FILE, NAME);            \
 330   } while (0)
 331
 332 /* We can't handle weak aliases, and therefore can't support pragma weak.
 333    Suppress the use of pragma weak in gthr-dce.h and gthr-posix.h.  */
 334 #define GTHREAD_USE_WEAK 0
 335
 336 /* Shared library suffix.  Collect2 strips the version string after
 337    this suffix when generating constructor/destructor names.  */
 338 #define SHLIB_SUFFIX ".sl"
 339
 340 /* We don't have named sections.  */
 341 #define TARGET_HAVE_NAMED_SECTIONS false
 342
 343 #define TARGET_ASM_TM_CLONE_TABLE_SECTION pa_som_tm_clone_table_section
 344
 345 /* Generate specially named labels to identify DWARF 2 frame unwind
 346    information.  */
 347 #define EH_FRAME_THROUGH_COLLECT2