gcc/xcoffout.c

   1 /* Output xcoff-format symbol table information from GNU compiler.
   2    Copyright (C) 1992-2021 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 it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 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 /* Output xcoff-format symbol table data.  The main functionality is contained
  21    in dbxout.c.  This file implements the sdbout-like parts of the xcoff
  22    interface.  Many functions are very similar to their counterparts in
  23    the former sdbout.c file.  */
  24
  25 #include "config.h"
  26 #include "system.h"
  27 #include "coretypes.h"
  28 #include "target.h"
  29 #include "rtl.h"
  30 #include "tree.h"
  31 #include "diagnostic-core.h"
  32 #include "varasm.h"
  33 #include "output.h"
  34 #include "debug.h"
  35 #include "file-prefix-map.h" /* remap_debug_filename()  */
  36
  37 #ifdef XCOFF_DEBUGGING_INFO
  38
  39 /* This defines the C_* storage classes.  */
  40 #include "xcoff.h"
  41 #include "xcoffout.h"
  42 #include "dbxout.h"
  43 #include "gstab.h"
  44
  45 /* Line number of beginning of current function, minus one.
  46    Negative means not in a function or not using xcoff.  */
  47
  48 static int xcoff_begin_function_line = -1;
  49 static int xcoff_inlining = 0;
  50
  51 /* Name of the current include file.  */
  52
  53 const char *xcoff_current_include_file;
  54
  55 /* Name of the current function file.  This is the file the `.bf' is
  56    emitted from.  In case a line is emitted from a different file,
  57    (by including that file of course), then the line number will be
  58    absolute.  */
  59
  60 static const char *xcoff_current_function_file;
  61
  62 /* Names of bss and data sections.  These should be unique names for each
  63    compilation unit.  */
  64
  65 char *xcoff_bss_section_name;
  66 char *xcoff_private_data_section_name;
  67 char *xcoff_private_rodata_section_name;
  68 char *xcoff_tls_data_section_name;
  69 char *xcoff_read_only_section_name;
  70
  71 /* Last source file name mentioned in a NOTE insn.  */
  72
  73 const char *xcoff_lastfile;
  74 \f
  75 /* Macro definitions used below.  */
  76
  77 #define ABS_OR_RELATIVE_LINENO(LINENO)          \
  78 ((xcoff_inlining) ? (LINENO) : (LINENO) - xcoff_begin_function_line)
  79
  80 /* Output source line numbers via ".line".  */
  81 #define ASM_OUTPUT_LINE(FILE,LINENUM)                                      \
  82   do                                                                       \
  83     {                                                                      \
  84       /* Make sure we're in a function and prevent output of .line 0, as   \
  85          line # 0 is meant for symbol addresses in xcoff.  Additionally,   \
  86          line numbers are 'unsigned short' in 32-bit mode.  */             \
  87       if (xcoff_begin_function_line >= 0)                                  \
  88         {                                                                  \
  89           int lno = ABS_OR_RELATIVE_LINENO (LINENUM);                      \
  90           if (lno > 0 && (TARGET_64BIT || lno <= (int)USHRT_MAX))          \
  91             fprintf (FILE, "\t.line\t%d\n", lno);                          \
  92         }                                                                  \
  93     }                                                                      \
  94   while (0)
  95
  96 #define ASM_OUTPUT_LFB(FILE,LINENUM) \
  97 {                                               \
  98   if (xcoff_begin_function_line == -1)          \
  99     {                                           \
 100       xcoff_begin_function_line = (LINENUM) - 1;\
 101       fprintf (FILE, "\t.bf\t%d\n", (LINENUM)); \
 102     }                                           \
 103   xcoff_current_function_file                   \
 104     = (xcoff_current_include_file               \
 105        ? xcoff_current_include_file : main_input_filename); \
 106 }
 107
 108 #define ASM_OUTPUT_LFE(FILE,LINENUM)            \
 109   do                                            \
 110     {                                           \
 111       fprintf (FILE, "\t.ef\t%d\n", (LINENUM)); \
 112       xcoff_begin_function_line = -1;           \
 113     }                                           \
 114   while (0)
 115
 116 #define ASM_OUTPUT_LBB(FILE,LINENUM,BLOCKNUM) \
 117   fprintf (FILE, "\t.bb\t%d\n", ABS_OR_RELATIVE_LINENO (LINENUM))
 118
 119 #define ASM_OUTPUT_LBE(FILE,LINENUM,BLOCKNUM) \
 120   fprintf (FILE, "\t.eb\t%d\n", ABS_OR_RELATIVE_LINENO (LINENUM))
 121
 122 static void xcoffout_block (tree, int, tree);
 123 static void xcoffout_source_file (FILE *, const char *, int);
 124 \f
 125 /* Support routines for XCOFF debugging info.  */
 126
 127 struct xcoff_type_number
 128 {
 129   const char *name;
 130   int number;
 131 };
 132 static const struct xcoff_type_number xcoff_type_numbers[] = {
 133   { "int", -1 },
 134   { "char", -2 },
 135   { "short int", -3 },
 136   { "long int", -4 },  /* fiddled to -31 if 64 bits */
 137   { "unsigned char", -5 },
 138   { "signed char", -6 },
 139   { "short unsigned int", -7 },
 140   { "unsigned int", -8 },
 141   /* No such type "unsigned".  */
 142   { "long unsigned int", -10 }, /* fiddled to -32 if 64 bits */
 143   { "void", -11 },
 144   { "float", -12 },
 145   { "double", -13 },
 146   { "long double", -14 },
 147   /* Fortran types run from -15 to -29.  */
 148   { "wchar", -30 },  /* XXX Should be "wchar_t" ? */
 149   { "long long int", -31 },
 150   { "long long unsigned int", -32 },
 151   /* Additional Fortran types run from -33 to -37.  */
 152
 153   /* ??? Should also handle built-in C++ and Obj-C types.  There perhaps
 154      aren't any that C doesn't already have.  */
 155 };
 156
 157 /* Returns an XCOFF fundamental type number for DECL (assumed to be a
 158    TYPE_DECL), or 0 if dbxout.c should assign a type number normally.  */
 159 int
 160 xcoff_assign_fundamental_type_number (tree decl)
 161 {
 162   const char *name;
 163   size_t i;
 164
 165   /* Do not waste time searching the list for non-intrinsic types.  */
 166   if (DECL_NAME (decl) == 0 || ! DECL_IS_UNDECLARED_BUILTIN (decl))
 167     return 0;
 168
 169   name = IDENTIFIER_POINTER (DECL_NAME (decl));
 170
 171   /* Linear search, blech, but the list is too small to bother
 172      doing anything else.  */
 173   for (i = 0; i < ARRAY_SIZE (xcoff_type_numbers); i++)
 174     if (!strcmp (xcoff_type_numbers[i].name, name))
 175       goto found;
 176   return 0;
 177
 178  found:
 179   /* -4 and -10 should be replaced with -31 and -32, respectively,
 180      when used for a 64-bit type.  */
 181   if (int_size_in_bytes (TREE_TYPE (decl)) == 8)
 182     {
 183       if (xcoff_type_numbers[i].number == -4)
 184         return -31;
 185       if (xcoff_type_numbers[i].number == -10)
 186         return -32;
 187     }
 188   return xcoff_type_numbers[i].number;
 189 }
 190
 191 /* Print an error message for unrecognized stab codes.  */
 192
 193 #define UNKNOWN_STAB(STR)       \
 194   internal_error ("no sclass for %s stab (0x%x)", STR, stab)
 195
 196 /* Conversion routine from BSD stabs to AIX storage classes.  */
 197
 198 int
 199 stab_to_sclass (int stab)
 200 {
 201   switch (stab)
 202     {
 203     case N_GSYM:
 204       return C_GSYM;
 205
 206     case N_FNAME:
 207       UNKNOWN_STAB ("N_FNAME");
 208
 209     case N_FUN:
 210       return C_FUN;
 211
 212     case N_STSYM:
 213     case N_LCSYM:
 214       return C_STSYM;
 215
 216     case N_MAIN:
 217       UNKNOWN_STAB ("N_MAIN");
 218
 219     case N_RSYM:
 220       return C_RSYM;
 221
 222     case N_SSYM:
 223       UNKNOWN_STAB ("N_SSYM");
 224
 225     case N_RPSYM:
 226       return C_RPSYM;
 227
 228     case N_PSYM:
 229       return C_PSYM;
 230     case N_LSYM:
 231       return C_LSYM;
 232     case N_DECL:
 233       return C_DECL;
 234     case N_ENTRY:
 235       return C_ENTRY;
 236
 237     case N_SO:
 238       UNKNOWN_STAB ("N_SO");
 239
 240     case N_SOL:
 241       UNKNOWN_STAB ("N_SOL");
 242
 243     case N_SLINE:
 244       UNKNOWN_STAB ("N_SLINE");
 245
 246     case N_DSLINE:
 247       UNKNOWN_STAB ("N_DSLINE");
 248
 249     case N_BSLINE:
 250       UNKNOWN_STAB ("N_BSLINE");
 251
 252     case N_BINCL:
 253       UNKNOWN_STAB ("N_BINCL");
 254
 255     case N_EINCL:
 256       UNKNOWN_STAB ("N_EINCL");
 257
 258     case N_EXCL:
 259       UNKNOWN_STAB ("N_EXCL");
 260
 261     case N_LBRAC:
 262       UNKNOWN_STAB ("N_LBRAC");
 263
 264     case N_RBRAC:
 265       UNKNOWN_STAB ("N_RBRAC");
 266
 267     case N_BCOMM:
 268       return C_BCOMM;
 269     case N_ECOMM:
 270       return C_ECOMM;
 271     case N_ECOML:
 272       return C_ECOML;
 273
 274     case N_LENG:
 275       UNKNOWN_STAB ("N_LENG");
 276
 277     case N_PC:
 278       UNKNOWN_STAB ("N_PC");
 279
 280     case N_M2C:
 281       UNKNOWN_STAB ("N_M2C");
 282
 283     case N_SCOPE:
 284       UNKNOWN_STAB ("N_SCOPE");
 285
 286     case N_CATCH:
 287       UNKNOWN_STAB ("N_CATCH");
 288
 289     case N_OPT:
 290       UNKNOWN_STAB ("N_OPT");
 291
 292     default:
 293       UNKNOWN_STAB ("?");
 294     }
 295 }
 296 \f
 297 /* Output debugging info to FILE to switch to sourcefile FILENAME.
 298    INLINE_P is true if this is from an inlined function.  */
 299
 300 static void
 301 xcoffout_source_file (FILE *file, const char *filename, int inline_p)
 302 {
 303   if (filename
 304       && (xcoff_lastfile == 0 || strcmp (filename, xcoff_lastfile)
 305           || (inline_p && ! xcoff_inlining)
 306           || (! inline_p && xcoff_inlining)))
 307     {
 308       if (xcoff_current_include_file)
 309         {
 310           fprintf (file, "\t.ei\t");
 311           output_quoted_string (file,
 312               remap_debug_filename (xcoff_current_include_file));
 313           fprintf (file, "\n");
 314           xcoff_current_include_file = NULL;
 315         }
 316       xcoff_inlining = inline_p;
 317       if (strcmp (main_input_filename, filename) || inline_p)
 318         {
 319           fprintf (file, "\t.bi\t");
 320           output_quoted_string (file, remap_debug_filename (filename));
 321           fprintf (file, "\n");
 322           xcoff_current_include_file = filename;
 323         }
 324       xcoff_lastfile = filename;
 325     }
 326 }
 327
 328 /* Output a line number symbol entry for location (FILENAME, LINE).  */
 329
 330 void
 331 xcoffout_source_line (unsigned int line, unsigned int column ATTRIBUTE_UNUSED,
 332                       const char *filename, int discriminator ATTRIBUTE_UNUSED,
 333                       bool is_stmt ATTRIBUTE_UNUSED)
 334 {
 335   bool inline_p = (strcmp (xcoff_current_function_file, filename) != 0
 336                    || (int) line < xcoff_begin_function_line);
 337
 338   xcoffout_source_file (asm_out_file, filename, inline_p);
 339
 340   ASM_OUTPUT_LINE (asm_out_file, line);
 341 }
 342 \f
 343 /* Output the symbols defined in block number DO_BLOCK.
 344
 345    This function works by walking the tree structure of blocks,
 346    counting blocks until it finds the desired block.  */
 347
 348 static unsigned int do_block = 0;
 349
 350 static void
 351 xcoffout_block (tree block, int depth, tree args)
 352 {
 353   while (block)
 354     {
 355       /* Ignore blocks never expanded or otherwise marked as real.  */
 356       if (TREE_USED (block))
 357         {
 358           /* When we reach the specified block, output its symbols.  */
 359           if (BLOCK_NUMBER (block) == do_block)
 360             {
 361               /* Output the syms of the block.  */
 362               if (debug_info_level != DINFO_LEVEL_TERSE || depth == 0)
 363                 dbxout_syms (BLOCK_VARS (block));
 364               if (args)
 365                 dbxout_reg_parms (args);
 366
 367               /* We are now done with the block.  Don't go to inner blocks.  */
 368               return;
 369             }
 370           /* If we are past the specified block, stop the scan.  */
 371           else if (BLOCK_NUMBER (block) >= do_block)
 372             return;
 373
 374           /* Output the subblocks.  */
 375           xcoffout_block (BLOCK_SUBBLOCKS (block), depth + 1, NULL_TREE);
 376         }
 377       block = BLOCK_CHAIN (block);
 378     }
 379 }
 380
 381 /* Describe the beginning of an internal block within a function.
 382    Also output descriptions of variables defined in this block.
 383
 384    N is the number of the block, by order of beginning, counting from 1,
 385    and not counting the outermost (function top-level) block.
 386    The blocks match the BLOCKs in DECL_INITIAL (current_function_decl),
 387    if the count starts at 0 for the outermost one.  */
 388
 389 void
 390 xcoffout_begin_block (unsigned int line, unsigned int n)
 391 {
 392   tree decl = current_function_decl;
 393
 394   /* The IBM AIX compiler does not emit a .bb for the function level scope,
 395      so we avoid it here also.  */
 396   if (n != 1)
 397     ASM_OUTPUT_LBB (asm_out_file, line, n);
 398
 399   do_block = n;
 400   xcoffout_block (DECL_INITIAL (decl), 0, DECL_ARGUMENTS (decl));
 401 }
 402
 403 /* Describe the end line-number of an internal block within a function.  */
 404
 405 void
 406 xcoffout_end_block (unsigned int line, unsigned int n)
 407 {
 408   if (n != 1)
 409     ASM_OUTPUT_LBE (asm_out_file, line, n);
 410 }
 411
 412 /* Called at beginning of function (before prologue).
 413    Declare function as needed for debugging.  */
 414
 415 void
 416 xcoffout_declare_function (FILE *file, tree decl, const char *name)
 417 {
 418   size_t len;
 419
 420   if (*name == '*')
 421     name++;
 422   len = strlen (name);
 423   if (name[len - 1] == ']')
 424     {
 425       char *n = XALLOCAVEC (char, len - 3);
 426       memcpy (n, name, len - 4);
 427       n[len - 4] = '\0';
 428       name = n;
 429     }
 430
 431   /* Any pending .bi or .ei must occur before the .function pseudo op.
 432      Otherwise debuggers will think that the function is in the previous
 433      file and/or at the wrong line number.  */
 434   xcoffout_source_file (file, DECL_SOURCE_FILE (decl), 0);
 435   dbxout_symbol (decl, 0);
 436
 437   /* .function NAME, TOP, MAPPING, TYPE, SIZE
 438      16 and 044 are placeholders for backwards compatibility */
 439   fprintf (file, "\t.function .%s,.%s,16,044,FE..%s-.%s\n",
 440            name, name, name, name);
 441 }
 442
 443 /* Called at beginning of function body (at start of prologue).
 444    Record the function's starting line number, so we can output
 445    relative line numbers for the other lines.
 446    Record the file name that this function is contained in.  */
 447
 448 void
 449 xcoffout_begin_prologue (unsigned int line,
 450                          unsigned int column ATTRIBUTE_UNUSED,
 451                          const char *file ATTRIBUTE_UNUSED)
 452 {
 453   ASM_OUTPUT_LFB (asm_out_file, line);
 454   dbxout_parms (DECL_ARGUMENTS (current_function_decl));
 455
 456   /* Emit the symbols for the outermost BLOCK's variables.  sdbout.c did this
 457      in sdbout_begin_block, but there is no guarantee that there will be any
 458      inner block 1, so we must do it here.  This gives a result similar to
 459      dbxout, so it does make some sense.  */
 460   do_block = BLOCK_NUMBER (DECL_INITIAL (current_function_decl));
 461   xcoffout_block (DECL_INITIAL (current_function_decl), 0,
 462                   DECL_ARGUMENTS (current_function_decl));
 463
 464   ASM_OUTPUT_LINE (asm_out_file, line);
 465 }
 466
 467 /* Called at end of function (before epilogue).
 468    Describe end of outermost block.  */
 469
 470 void
 471 xcoffout_end_function (unsigned int last_linenum)
 472 {
 473   ASM_OUTPUT_LFE (asm_out_file, last_linenum);
 474 }
 475
 476 /* Output xcoff info for the absolute end of a function.
 477    Called after the epilogue is output.  */
 478
 479 void
 480 xcoffout_end_epilogue (unsigned int line ATTRIBUTE_UNUSED,
 481                        const char *file ATTRIBUTE_UNUSED)
 482 {
 483   /* We need to pass the correct function size to .function, otherwise,
 484      the xas assembler can't figure out the correct size for the function
 485      aux entry.  So, we emit a label after the last instruction which can
 486      be used by the .function pseudo op to calculate the function size.  */
 487
 488   const char *fname = XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0);
 489   if (*fname == '*')
 490     ++fname;
 491   fprintf (asm_out_file, "FE..");
 492   ASM_OUTPUT_LABEL (asm_out_file, fname);
 493 }
 494 #endif /* XCOFF_DEBUGGING_INFO */