gcc/config/svr3.h

   1 /* Operating system specific defines to be used when targeting GCC for
   2    generic System V Release 3 system.
   3    Copyright (C) 1991, 1996 Free Software Foundation, Inc.
   4    Contributed by Ron Guilmette (rfg@monkeys.com).
   5
   6 This file is part of GNU CC.
   7
   8 GNU CC 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 GNU CC 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 GNU CC; see the file COPYING.  If not, write to
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.
  22
  23    To use this file, make up a file with a name like:
  24
  25         ?????svr3.h
  26
  27    where ????? is replaced by the name of the basic hardware that you
  28    are targeting for.  Then, in the file ?????svr3.h, put something
  29    like:
  30
  31         #include "?????.h"
  32         #include "svr3.h"
  33
  34    followed by any really system-specific defines (or overrides of
  35    defines) which you find that you need.  For example, CPP_PREDEFINES
  36    is defined here with only the defined -Dunix and -DSVR3.  You should
  37    probably override that in your target-specific ?????svr3.h file
  38    with a set of defines that includes these, but also contains an
  39    appropriate define for the type of hardware that you are targeting.
  40 */
  41
  42 /* Define a symbol indicating that we are using svr3.h.  */
  43 #define USING_SVR3_H
  44
  45 /* Define a symbol so that libgcc* can know what sort of operating
  46    environment and assembler syntax we are targeting for.  */
  47 #define SVR3_target
  48
  49 /* Cpp, assembler, linker, library, and startfile spec's.  */
  50
  51 /* You should redefine CPP_PREDEFINES in any file which includes this one.
  52    The definition should be appropriate for the type of target system
  53    involved, and it should include any -A (assertion) options which are
  54    appropriate for the given target system.  */
  55
  56 #undef CPP_PREDEFINES
  57
  58 /* Output at beginning of assembler file.  */
  59 /* The .file command should always begin the output.  */
  60
  61 #undef ASM_FILE_START
  62 #define ASM_FILE_START(FILE)                                    \
  63   do { output_file_directive ((FILE), main_input_filename);     \
  64        if (optimize) { ASM_FILE_START_1 (FILE); }               \
  65      } while (0)
  66
  67 /* By default, do nothing: a few machines support .optim, but not most.  */
  68 #undef ASM_FILE_START_1
  69 #define ASM_FILE_START_1(FILE)
  70
  71 /* This says how to output an assembler line
  72    to define a global common symbol.  */
  73 /* We don't use ROUNDED because the standard compiler doesn't,
  74    and the linker gives error messages if a common symbol
  75    has more than one length value.  */
  76
  77 #undef ASM_OUTPUT_COMMON
  78 #define ASM_OUTPUT_COMMON(FILE, NAME, SIZE, ROUNDED)  \
  79 ( fputs (".comm ", (FILE)),                     \
  80   assemble_name ((FILE), (NAME)),               \
  81   fprintf ((FILE), ",%u\n", (SIZE)))
  82
  83 /* This says how to output an assembler line
  84    to define a local common symbol.  */
  85
  86 /* Note that using bss_section here caused errors
  87    in building shared libraries on system V.3.  */
  88 #undef ASM_OUTPUT_LOCAL
  89 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
  90   do {                                                  \
  91     int align = exact_log2 (ROUNDED);                   \
  92     if (align > 2) align = 2;                           \
  93     data_section ();                                    \
  94     ASM_OUTPUT_ALIGN ((FILE), align == -1 ? 2 : align); \
  95     ASM_OUTPUT_LABEL ((FILE), (NAME));                  \
  96     fprintf ((FILE), "\t.set .,.+%u\n", (ROUNDED));     \
  97   } while (0)
  98
  99 #if 0 /* For now, let's leave these machine-specific.  */
 100 /* Use crt1.o as a startup file and crtn.o as a closing file.  */
 101
 102 #define STARTFILE_SPEC  \
 103   "%{pg:gcrt1.o%s}%{!pg:%{p:mcrt1.o%s}%{!p:crt1.o%s}}"
 104
 105 #ifdef CROSS_COMPILE
 106 #define LIB_SPEC "-lc crtn.o%s"
 107 #else
 108 #define LIB_SPEC "%{p:-L/usr/lib/libp}%{pg:-L/usr/lib/libp} -lc crtn.o%s"
 109 #endif
 110
 111 /* Special flags for the linker.  I don't know what they do.  */
 112
 113 #define LINK_SPEC "%{T*} %{z:-lm}"
 114 #endif
 115
 116 /* Allow #sccs in preprocessor.  */
 117
 118 #define SCCS_DIRECTIVE
 119
 120 /* Output #ident as a .ident.  */
 121
 122 #define ASM_OUTPUT_IDENT(FILE, NAME) \
 123   fprintf (FILE, "\t.ident \"%s\"\n", NAME);
 124
 125 /* Use periods rather than dollar signs in special g++ assembler names.  */
 126
 127 #define NO_DOLLAR_IN_LABEL
 128
 129 /* Implicit library calls should use memcpy, not bcopy, etc.  */
 130
 131 #define TARGET_MEM_FUNCTIONS
 132
 133 /* System V Release 3 uses COFF debugging info.  */
 134
 135 #define SDB_DEBUGGING_INFO
 136
 137 /* We don't want to output DBX debugging information.  */
 138
 139 #undef DBX_DEBUGGING_INFO
 140
 141 /* Define the actual types of some ANSI-mandated types.  These
 142    definitions should work for most SVR3 systems.  */
 143
 144 #undef SIZE_TYPE
 145 #define SIZE_TYPE "unsigned int"
 146
 147 #undef PTRDIFF_TYPE
 148 #define PTRDIFF_TYPE "int"
 149
 150 #undef WCHAR_TYPE
 151 #define WCHAR_TYPE "long int"
 152
 153 #undef WCHAR_TYPE_SIZE
 154 #define WCHAR_TYPE_SIZE BITS_PER_WORD
 155
 156 /* Assembler pseudos to introduce constants of various size.  These
 157    definitions should work for most svr3 systems.  */
 158
 159 #undef ASM_BYTE_OP
 160 #define ASM_BYTE_OP "\t.byte"
 161
 162 /* The prefix to add to user-visible assembler symbols.
 163
 164    For System V Release 3 the convention is to prepend a leading
 165    underscore onto user-level symbol names.  */
 166
 167 #undef USER_LABEL_PREFIX
 168 #define USER_LABEL_PREFIX "_"
 169
 170 /* This is how to output an internal numbered label where
 171    PREFIX is the class of label and NUM is the number within the class.
 172
 173    For most svr3 systems, the convention is that any symbol which begins
 174    with a period is not put into the linker symbol table by the assembler.  */
 175
 176 #undef ASM_OUTPUT_INTERNAL_LABEL
 177 #define ASM_OUTPUT_INTERNAL_LABEL(FILE,PREFIX,NUM)      \
 178   asm_fprintf (FILE, "%0L%s%d:\n", PREFIX, NUM)
 179
 180 /* This is how to store into the string LABEL
 181    the symbol_ref name of an internal numbered label where
 182    PREFIX is the class of label and NUM is the number within the class.
 183    This is suitable for output with `assemble_name'.
 184
 185    For most svr3 systems, the convention is that any symbol which begins
 186    with a period is not put into the linker symbol table by the assembler.  */
 187
 188 #undef ASM_GENERATE_INTERNAL_LABEL
 189 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
 190   sprintf (LABEL, "*%s%s%d", LOCAL_LABEL_PREFIX, PREFIX, NUM)
 191
 192 /* We want local labels to start with period if made with asm_fprintf.  */
 193 #undef LOCAL_LABEL_PREFIX
 194 #define LOCAL_LABEL_PREFIX "."
 195
 196 /* Support const sections and the ctors and dtors sections for g++.
 197    Note that there appears to be two different ways to support const
 198    sections at the moment.  You can either #define the symbol
 199    READONLY_DATA_SECTION (giving it some code which switches to the
 200    readonly data section) or else you can #define the symbols
 201    EXTRA_SECTIONS, EXTRA_SECTION_FUNCTIONS, SELECT_SECTION, and
 202    SELECT_RTX_SECTION.  We do both here just to be on the safe side.
 203    However, use of the const section is turned off by default
 204    unless the specific tm.h file turns it on by defining
 205    USE_CONST_SECTION as 1.  */
 206
 207 /* Define a few machine-specific details of the implementation of
 208    constructors.
 209
 210    The __CTORS_LIST__ goes in the .init section.  Define CTOR_LIST_BEGIN
 211    and CTOR_LIST_END to contribute to the .init section an instruction to
 212    push a word containing 0 (or some equivalent of that).
 213
 214    Define ASM_OUTPUT_CONSTRUCTOR to push the address of the constructor.  */
 215
 216 #define USE_CONST_SECTION       0
 217
 218 #define INIT_SECTION_ASM_OP     ".section\t.init"
 219 #define FINI_SECTION_ASM_OP     ".section .fini,\"x\""
 220 #define CONST_SECTION_ASM_OP    ".section\t.rodata, \"x\""
 221 #define CTORS_SECTION_ASM_OP    INIT_SECTION_ASM_OP
 222 #define DTORS_SECTION_ASM_OP    FINI_SECTION_ASM_OP
 223
 224 /* CTOR_LIST_BEGIN and CTOR_LIST_END are machine-dependent
 225    because they push on the stack.  */
 226
 227 #ifndef STACK_GROWS_DOWNWARD
 228
 229 /* Constructor list on stack is in reverse order.  Go to the end of the
 230    list and go backwards to call constructors in the right order.  */
 231 #define DO_GLOBAL_CTORS_BODY                                    \
 232 do {                                                            \
 233   func_ptr *p, *beg = alloca (0);                               \
 234   for (p = beg; *p; p++)                                        \
 235     ;                                                           \
 236   while (p != beg)                                              \
 237     (*--p) ();                                                  \
 238 } while (0)
 239
 240 #else
 241
 242 /* Constructor list on stack is in correct order.  Just call them.  */
 243 #define DO_GLOBAL_CTORS_BODY                                    \
 244 do {                                                            \
 245   func_ptr *p, *beg = alloca (0);                               \
 246   for (p = beg; *p; )                                           \
 247     (*p++) ();                                                  \
 248 } while (0)
 249
 250 #endif /* STACK_GROWS_DOWNWARD */
 251
 252 /* Add extra sections .rodata, .init and .fini.  */
 253
 254 #undef EXTRA_SECTIONS
 255 #define EXTRA_SECTIONS in_const, in_init, in_fini
 256
 257 #undef EXTRA_SECTION_FUNCTIONS
 258 #define EXTRA_SECTION_FUNCTIONS                                 \
 259   CONST_SECTION_FUNCTION                                        \
 260   INIT_SECTION_FUNCTION                                         \
 261   FINI_SECTION_FUNCTION
 262
 263 #define INIT_SECTION_FUNCTION                                   \
 264 void                                                            \
 265 init_section ()                                                 \
 266 {                                                               \
 267   if (in_section != in_init)                                    \
 268     {                                                           \
 269       fprintf (asm_out_file, "\t%s\n", INIT_SECTION_ASM_OP);    \
 270       in_section = in_init;                                     \
 271     }                                                           \
 272 }
 273
 274 #define FINI_SECTION_FUNCTION                                   \
 275 void                                                            \
 276 fini_section ()                                                 \
 277 {                                                               \
 278   if (in_section != in_fini)                                    \
 279     {                                                           \
 280       fprintf (asm_out_file, "\t%s\n", FINI_SECTION_ASM_OP);    \
 281       in_section = in_fini;                                     \
 282     }                                                           \
 283 }
 284
 285 #define READONLY_DATA_SECTION() const_section ()
 286
 287 #define CONST_SECTION_FUNCTION                                          \
 288 void                                                                    \
 289 const_section ()                                                        \
 290 {                                                                       \
 291   if (!USE_CONST_SECTION)                                               \
 292     text_section();                                                     \
 293   else if (in_section != in_const)                                      \
 294     {                                                                   \
 295       fprintf (asm_out_file, "%s\n", CONST_SECTION_ASM_OP);             \
 296       in_section = in_const;                                            \
 297     }                                                                   \
 298 }
 299
 300 /* The ctors and dtors sections are not normally put into use
 301    by EXTRA_SECTIONS and EXTRA_SECTION_FUNCTIONS as defined in svr3.h,
 302    but it can't hurt to define these macros for whatever systems use them.  */
 303 #define CTORS_SECTION_FUNCTION                                          \
 304 void                                                                    \
 305 ctors_section ()                                                        \
 306 {                                                                       \
 307   if (in_section != in_ctors)                                           \
 308     {                                                                   \
 309       fprintf (asm_out_file, "%s\n", CTORS_SECTION_ASM_OP);             \
 310       in_section = in_ctors;                                            \
 311     }                                                                   \
 312 }
 313
 314 #define DTORS_SECTION_FUNCTION                                          \
 315 void                                                                    \
 316 dtors_section ()                                                        \
 317 {                                                                       \
 318   if (in_section != in_dtors)                                           \
 319     {                                                                   \
 320       fprintf (asm_out_file, "%s\n", DTORS_SECTION_ASM_OP);             \
 321       in_section = in_dtors;                                            \
 322     }                                                                   \
 323 }
 324
 325 /* This is machine-dependent
 326    because it needs to push something on the stack.  */
 327 #undef ASM_OUTPUT_CONSTRUCTOR
 328
 329 /* A C statement (sans semicolon) to output an element in the table of
 330    global destructors.  */
 331 #define ASM_OUTPUT_DESTRUCTOR(FILE,NAME)                                \
 332   do {                                                                  \
 333     fini_section ();                                            \
 334     fprintf (FILE, "%s\t ", ASM_LONG);                                  \
 335     assemble_name (FILE, NAME);                                         \
 336     fprintf (FILE, "\n");                                               \
 337   } while (0)
 338
 339 /* A C statement or statements to switch to the appropriate
 340    section for output of DECL.  DECL is either a `VAR_DECL' node
 341    or a constant of some sort.  RELOC indicates whether forming
 342    the initial value of DECL requires link-time relocations.  */
 343
 344 #define SELECT_SECTION(DECL,RELOC)                                      \
 345 {                                                                       \
 346   if (TREE_CODE (DECL) == STRING_CST)                                   \
 347     {                                                                   \
 348       if (! flag_writable_strings)                                      \
 349         const_section ();                                               \
 350       else                                                              \
 351         data_section ();                                                \
 352     }                                                                   \
 353   else if (TREE_CODE (DECL) == VAR_DECL)                                \
 354     {                                                                   \
 355       if ((0 && RELOC)  /* should be (flag_pic && RELOC) */             \
 356           || !TREE_READONLY (DECL) || TREE_SIDE_EFFECTS (DECL)          \
 357           || !DECL_INITIAL (DECL)                                       \
 358           || (DECL_INITIAL (DECL) != error_mark_node                    \
 359               && !TREE_CONSTANT (DECL_INITIAL (DECL))))                 \
 360         data_section ();                                                \
 361       else                                                              \
 362         const_section ();                                               \
 363     }                                                                   \
 364   else                                                                  \
 365     const_section ();                                                   \
 366 }
 367
 368 /* A C statement or statements to switch to the appropriate
 369    section for output of RTX in mode MODE.  RTX is some kind
 370    of constant in RTL.  The argument MODE is redundant except
 371    in the case of a `const_int' rtx.  Currently, these always
 372    go into the const section.  */
 373
 374 #define SELECT_RTX_SECTION(MODE,RTX) const_section()