Annotation of gcc/dbxout.c, revision 1.1.1.2

1.1       root        1: /* Output dbx-format symbol table information from GNU compiler.
                      2:    Copyright (C) 1987 Free Software Foundation, Inc.
                      3: 
                      4: This file is part of GNU CC.
                      5: 
                      6: GNU CC is distributed in the hope that it will be useful,
                      7: but WITHOUT ANY WARRANTY.  No author or distributor
                      8: accepts responsibility to anyone for the consequences of using it
                      9: or for whether it serves any particular purpose or works at all,
                     10: unless he says so in writing.  Refer to the GNU CC General Public
                     11: License for full details.
                     12: 
                     13: Everyone is granted permission to copy, modify and redistribute
                     14: GNU CC, but only under the conditions described in the
                     15: GNU CC General Public License.   A copy of this license is
                     16: supposed to have been given to you along with GNU CC so you
                     17: can know your rights and responsibilities.  It should be in a
                     18: file named COPYING.  Among other things, the copyright notice
                     19: and this notice must be preserved on all copies.  */
                     20: 
                     21: 
                     22: /* Output dbx-format symbol table data.
                     23:    This consists of many symbol table entries, each of them
                     24:    a .stabs assembler pseudo-op with four operands:
                     25:    a "name" which is really a description of one symbol and its type,
                     26:    a "code", which is a symbol defined in stab.h whose name starts with N_,
                     27:    an unused operand always 0,
                     28:    and a "value" which is an address or an offset.
                     29:    The name is enclosed in doublequote characters.
                     30: 
                     31:    Each function, variable, typedef, and structure tag
                     32:    has a symbol table entry to define it.
                     33:    The beginning and end of each level of name scoping within
                     34:    a function are also marked by special symbol table entries.
                     35: 
                     36:    The "name" consists of the symbol name, a colon, a kind-of-symbol letter,
                     37:    and a data type number.  The data type number may be followed by
                     38:    "=" and a type definition; normally this will happen the first time
                     39:    the type number is mentioned.  The type definition may refer to
                     40:    other types by number, and those type numbers may be followed
                     41:    by "=" and nested definitions.
                     42: 
                     43:    This can make the "name" quite long.
                     44:    When a name is more than 80 characters, we split the .stabs pseudo-op
                     45:    into two .stabs pseudo-ops, both sharing the same "code" and "value".
                     46:    The first one is marked as continued with a double-backslash at the
                     47:    end of its "name".
                     48: 
                     49:    The kind-of-symbol letter distinguished function names from global
                     50:    variables from file-scope variables from parameters from auto
                     51:    variables in memory from typedef names from register variables.
                     52:    See `dbxout_symbol'.
                     53: 
                     54:    The "code" is mostly redundant with the kind-of-symbol letter
                     55:    that goes in the "name", but not entirely: for symbols located
                     56:    in static storage, the "code" says which segment the address is in,
                     57:    which controls how it is relocated.
                     58: 
                     59:    The "value" for a symbol in static storage
                     60:    is the core address of the symbol (actually, the assembler
                     61:    label for the symbol).  For a symbol located in a stack slot
                     62:    it is the stack offset; for one in a register, the register number.
                     63:    For a typedef symbol, it is zero.
                     64: 
                     65:    For more on data type definitions, see `dbxout_type'.  */
                     66: 
                     67: #include "config.h"
                     68: #include "tree.h"
                     69: #include "rtl.h"
                     70: #include <stdio.h>
1.1.1.2 ! root       71: 
        !            72: /* Typical USG systems don't have stab.h, and they also have
        !            73:    no use for DBX-format debugging info.  */
        !            74: 
        !            75: #ifndef NO_DBX_FORMAT
        !            76: 
1.1       root       77: #include <stab.h>
1.1.1.2 ! root       78: 
1.1       root       79: /* Stream for writing to assembler file.  */
                     80: 
                     81: static FILE *asmfile;
                     82: 
                     83: enum typestatus {TYPE_UNSEEN, TYPE_XREF, TYPE_DEFINED};
                     84: 
                     85: /* Vector recording the status of describing C data types.
                     86:    When we first notice a data type (a tree node),
                     87:    we assign it a number using next_type_number.
                     88:    That is its index in this vector.
                     89:    The vector element says whether we have yet output
                     90:    the definition of the type.  TYPE_XREF says we have
                     91:    output it as a cross-reference only.  */
                     92: 
                     93: enum typestatus *typevec;
                     94: 
                     95: /* Number of elements of space allocated in `typevec'.  */
                     96: 
                     97: static int typevec_len;
                     98: 
                     99: /* In dbx output, each type gets a unique number.
                    100:    This is the number for the next type output.
                    101:    The number, once assigned, is in the TYPE_SYMTAB_ADDRESS field.  */
                    102: 
                    103: static int next_type_number;
                    104: 
                    105: /* In dbx output, we must assign symbol-blocks id numbers
                    106:    in the order in which their beginnings are encountered.
                    107:    We output debugging info that refers to the beginning and
                    108:    end of the ranges of code in each block
                    109:    with assembler labels LBBn and LBEn, where n is the block number.
                    110:    The labels are generated in final, which assigns numbers to the
                    111:    blocks in the same way.  */
                    112: 
                    113: static int next_block_number;
                    114: 
                    115: /* These variables are for dbxout_symbol to communicate to
                    116:    dbxout_finish_symbol.
                    117:    current_sym_code is the symbol-type-code, a symbol N_... define in stab.h.
                    118:    current_sym_value and current_sym_addr are two ways to address the
                    119:    value to store in the symtab entry.
                    120:    current_sym_addr if nonzero represents the value as an rtx.
                    121:    If that is zero, current_sym_value is used.  This is used
                    122:    when the value is an offset (such as for auto variables,
                    123:    register variables and parms).  */
                    124: 
                    125: static int current_sym_code;
                    126: static int current_sym_value;
                    127: static rtx current_sym_addr;
                    128: 
                    129: /* Number of chars of symbol-description generated so far for the
                    130:    current symbol.  Used by CHARS and CONTIN.  */
                    131: 
                    132: static int current_sym_nchars;
                    133: 
                    134: /* Report having output N chars of the current symbol-description.  */
                    135: 
                    136: #define CHARS(N) (current_sym_nchars += (N))
                    137: 
                    138: /* Break the current symbol-description, generating a continuation,
                    139:    if it has become long.  */
                    140: 
1.1.1.2 ! root      141: #ifndef DBX_CONTIN_LENGTH
        !           142: #define DBX_CONTIN_LENGTH 80
        !           143: #endif
        !           144: 
        !           145: #if DBX_CONTIN_LENGTH > 0
1.1       root      146: #define CONTIN  \
1.1.1.2 ! root      147:   do {if (current_sym_nchars > DBX_CONTIN_LENGTH) dbxout_continue ();} while (0)
        !           148: #else
        !           149: #define CONTIN
        !           150: #endif
1.1       root      151: 
                    152: void dbxout_types ();
                    153: void dbxout_tags ();
                    154: static void dbxout_type_name ();
                    155: static void dbxout_type ();
                    156: static void dbxout_type_def ();
                    157: static void dbxout_finish_symbol ();
                    158: static void dbxout_continue ();
                    159: 
                    160: /* At the beginning of compilation, start writing the symbol table.
                    161:    Initialize `typevec' and output the standard data types of C.  */
                    162: 
                    163: void
                    164: dbxout_init (asm_file, input_file_name)
                    165:      FILE *asm_file;
                    166:      char *input_file_name;
                    167: {
                    168:   asmfile = asm_file;
                    169: 
                    170:   typevec_len = 100;
                    171:   typevec = (enum typestatus *) xmalloc (typevec_len * sizeof typevec[0]);
                    172:   bzero (typevec, typevec_len * sizeof typevec[0]);
                    173:   
                    174:   fprintf (asmfile,
                    175:           "Ltext:\t.stabs \"%s\",%d,0,0,Ltext\n",
1.1.1.2 ! root      176:           input_file_name, N_SO);
1.1       root      177: 
                    178:   next_type_number = 1;
                    179:   next_block_number = 2;
                    180: 
                    181:   /* Make sure that types `int' and `char' have numbers 1 and 2.
                    182:      Definitions of other integer types will refer to those numbers.  */
                    183: 
                    184:   dbxout_type_def (integer_type_node);
                    185:   dbxout_type_def (char_type_node);
                    186: 
1.1.1.2 ! root      187:   /* Get all permanent types not yet gotten, and output them.  */
1.1       root      188: 
                    189:   dbxout_types (get_permanent_types ());
                    190: }
                    191: 
                    192: /* Continue a symbol-description that gets too big.
                    193:    End one symbol table entry with a double-backslash
                    194:    and start a new one, eventually producing something like
                    195:    .stabs "start......\\",code,0,value
                    196:    .stabs "...rest",code,0,value   */
                    197: 
                    198: static void
                    199: dbxout_continue ()
                    200: {
1.1.1.2 ! root      201: #ifdef DBX_CONTIN_CHAR
        !           202:   fprintf (asmfile, "%c", DBX_CONTIN_CHAR);
        !           203: #else
1.1       root      204:   fprintf (asmfile, "\\\\");
1.1.1.2 ! root      205: #endif
1.1       root      206:   dbxout_finish_symbol ();
                    207:   fprintf (asmfile, ".stabs \"");
                    208:   current_sym_nchars = 0;
                    209: }
                    210: 
                    211: /* Output a reference to a type.  If the type has not yet been
                    212:    described in the dbx output, output its definition now.
                    213:    For a type already defined, just refer to its definition
                    214:    using the type number.
                    215: 
                    216:    If FULL is nonzero, and the type has been described only with
                    217:    a forward-reference, output the definition now.
                    218:    If FULL is zero in this case, just refer to the forward-reference
                    219:    using the number previously allocated.  */
                    220: 
                    221: static void
                    222: dbxout_type (type, full)
                    223:      tree type;
                    224:      int full;
                    225: {
                    226:   register tree tem;
                    227: 
1.1.1.2 ! root      228:   /* If there was an input error and we don't really have a type,
        !           229:      avoid crashing and write something that is at least valid
        !           230:      by assuming `int'.  */
        !           231:   if (type == error_mark_node)
        !           232:     type = integer_type_node;
        !           233:   else if (TYPE_SIZE (type) == 0)
        !           234:     type = TYPE_MAIN_VARIANT (type);
        !           235: 
1.1       root      236:   if (TYPE_SYMTAB_ADDRESS (type) == 0)
                    237:     {
                    238:       /* Type has no dbx number assigned.  Assign next available number.  */
                    239:       TYPE_SYMTAB_ADDRESS (type) = next_type_number++;
                    240: 
                    241:       /* Make sure type vector is long enough to record about this type.  */
                    242: 
                    243:       if (next_type_number == typevec_len)
                    244:        {
                    245:          typevec = (enum typestatus *) xrealloc (typevec, typevec_len * 2 * sizeof typevec[0]);
                    246:          bzero (typevec + typevec_len, typevec_len * sizeof typevec[0]);
                    247:          typevec_len *= 2;
                    248:        }
                    249:     }
                    250: 
                    251:   /* Output the number of this type, to refer to it.  */
                    252:   fprintf (asmfile, "%d", TYPE_SYMTAB_ADDRESS (type));
                    253:   CHARS (3);
                    254: 
                    255:   /* If this type's definition has been output or is now being output,
                    256:      that is all.  */
                    257: 
                    258:   switch (typevec[TYPE_SYMTAB_ADDRESS (type)])
                    259:     {
                    260:     case TYPE_UNSEEN:
                    261:       break;
                    262:     case TYPE_XREF:
                    263:       if (! full)
                    264:        return;
                    265:       break;
                    266:     case TYPE_DEFINED:
                    267:       return;
                    268:     }
                    269: 
1.1.1.2 ! root      270: #ifdef DBX_NO_XREFS
        !           271:   /* For systems where dbx output does not allow the `=xsNAME:' syntax,
        !           272:      leave the type-number completely undefined rather than output
        !           273:      a cross-reference.  */
        !           274:   if (TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
        !           275:       || TREE_CODE (type) == ENUMERAL_TYPE)
        !           276: 
        !           277:     if ((TYPE_NAME (type) != 0 && !full)
        !           278:        || TYPE_SIZE (type) == 0)
        !           279:       {
        !           280:        typevec[TYPE_SYMTAB_ADDRESS (type)] = TYPE_XREF;
        !           281:        return;
        !           282:       }
        !           283: #endif
        !           284: 
1.1       root      285:   /* Output a definition now.  */
                    286: 
                    287:   fprintf (asmfile, "=");
                    288:   CHARS (1);
                    289: 
                    290:   /* Mark it as defined, so that if it is self-referent
                    291:      we will not get into an infinite recursion of definitions.  */
                    292: 
                    293:   typevec[TYPE_SYMTAB_ADDRESS (type)] = TYPE_DEFINED;
                    294: 
                    295:   switch (TREE_CODE (type))
                    296:     {
                    297:     case VOID_TYPE:
                    298:       /* For a void type, just define it as itself; ie, "5=5".
                    299:         This makes us consider it defined
                    300:         without saying what it is.  The debugger will make it
                    301:         a void type when the reference is seen, and nothing will
                    302:         ever override that default.  */
                    303:       fprintf (asmfile, "%d", TYPE_SYMTAB_ADDRESS (type));
                    304:       CHARS (3);
                    305:       break;
                    306: 
                    307:     case INTEGER_TYPE:
1.1.1.2 ! root      308:       if (type == char_type_node && ! TREE_UNSIGNED (type))
1.1       root      309:        /* Output the type `char' as a subrange of itself!
                    310:           I don't understand this definition, just copied it
                    311:           from the output of pcc.  */
                    312:        fprintf (asmfile, "r2;0;127;");
                    313:       else
                    314:        /* Output other integer types as subranges of `int'.  */
                    315:        fprintf (asmfile, "r1;%d;%d;",
                    316:                 TREE_INT_CST_LOW (TYPE_MIN_VALUE (type)),
                    317:                 TREE_INT_CST_LOW (TYPE_MAX_VALUE (type)));
                    318:       CHARS (25);
                    319:       break;
                    320: 
                    321:     case REAL_TYPE:
                    322:       /* This must be magic.  */
                    323:       fprintf (asmfile, "r1;%d;0;",
                    324:               TREE_INT_CST_LOW (size_in_bytes (type)));
                    325:       CHARS (16);
                    326:       break;
                    327: 
                    328:     case ARRAY_TYPE:
                    329:       /* Output "a" followed by a range type definition
                    330:         for the index type of the array
                    331:         followed by a reference to the target-type.
                    332:         ar1;0;N;M for an array of type M and size N.  */
                    333:       fprintf (asmfile, "ar1;0;%d;",
1.1.1.2 ! root      334:               (TYPE_DOMAIN (type)
        !           335:                ? TREE_INT_CST_LOW (TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
        !           336:                : -1));
1.1       root      337:       CHARS (17);
                    338:       dbxout_type (TREE_TYPE (type), 0);
                    339:       break;
                    340: 
                    341:     case RECORD_TYPE:
                    342:     case UNION_TYPE:
                    343:       /* Output a structure type.  */
                    344:       if ((TYPE_NAME (type) != 0 && !full)
                    345:          || TYPE_SIZE (type) == 0)
                    346:        {
                    347:          /* If the type is just a cross reference, output one
                    348:             and mark the type as partially described.
                    349:             If it later becomes defined, we will output
1.1.1.2 ! root      350:             its real definition.
        !           351:             If the type has a name, don't nest its name within
        !           352:             another type's definition; instead, output an xref
        !           353:             and let the definition come when the name is defined.  */
1.1       root      354:          fprintf (asmfile, (TREE_CODE (type) == RECORD_TYPE) ? "xs" : "xu");
                    355:          CHARS (3);
                    356:          dbxout_type_name (type);
                    357:          fprintf (asmfile, ":");
                    358:          typevec[TYPE_SYMTAB_ADDRESS (type)] = TYPE_XREF;
                    359:          break;
                    360:        }
                    361:       tem = size_in_bytes (type);
                    362:       fprintf (asmfile, (TREE_CODE (type) == RECORD_TYPE) ? "s%d" : "u%d",
                    363:               TREE_INT_CST_LOW (tem));
                    364:       CHARS (11);
                    365:       for (tem = TYPE_FIELDS (type); tem; tem = TREE_CHAIN (tem))
                    366:        /* Output the name, type, position (in bits), size (in bits)
                    367:           of each field.  */
                    368:        /* Omit here the nameless fields that are used to skip bits.  */
                    369:        if (DECL_NAME (tem) != 0)
                    370:          {
1.1.1.2 ! root      371:            /* Continue the line if necessary,
        !           372:               but not before the first field.  */
        !           373:            if (tem != TYPE_FIELDS (type))
        !           374:              CONTIN;
1.1       root      375:            fprintf (asmfile, "%s:", IDENTIFIER_POINTER (DECL_NAME (tem)));
                    376:            CHARS (1 + strlen (IDENTIFIER_POINTER (DECL_NAME (tem))));
                    377:            dbxout_type (TREE_TYPE (tem), 0);
                    378:            fprintf (asmfile, ",%d,%d;", DECL_OFFSET (tem),
                    379:                     TREE_INT_CST_LOW (DECL_SIZE (tem)) * DECL_SIZE_UNIT (tem));
                    380:            CHARS (23);
                    381:          }
                    382:       putc (';', asmfile);
                    383:       CHARS (1);
                    384:       break;
                    385: 
                    386:     case ENUMERAL_TYPE:
                    387:       if ((TYPE_NAME (type) != 0 && !full)
                    388:          || TYPE_SIZE (type) == 0)
                    389:        {
                    390:          fprintf (asmfile, "xe");
                    391:          CHARS (3);
                    392:          dbxout_type_name (type);
                    393:          typevec[TYPE_SYMTAB_ADDRESS (type)] = TYPE_XREF;
                    394:          fprintf (asmfile, ":");
                    395:          return;
                    396:        }
                    397:       putc ('e', asmfile);
                    398:       CHARS (1);
                    399:       for (tem = TYPE_VALUES (type); tem; tem = TREE_CHAIN (tem))
                    400:        {
                    401:          fprintf (asmfile, "%s:%d,", IDENTIFIER_POINTER (TREE_PURPOSE (tem)),
                    402:                   TREE_INT_CST_LOW (TREE_VALUE (tem)));
                    403:          CHARS (11 + strlen (IDENTIFIER_POINTER (TREE_PURPOSE (tem))));
                    404:          if (TREE_CHAIN (tem) != 0)
                    405:            CONTIN;
                    406:        }
                    407:       putc (';', asmfile);
                    408:       CHARS (1);
                    409:       break;
                    410: 
                    411:     case POINTER_TYPE:
                    412:       putc ('*', asmfile);
                    413:       CHARS (1);
                    414:       dbxout_type (TREE_TYPE (type), 0);
                    415:       break;
                    416: 
                    417:     case FUNCTION_TYPE:
                    418:       putc ('f', asmfile);
                    419:       CHARS (1);
                    420:       dbxout_type (TREE_TYPE (type), 0);
                    421:       break;
                    422:     }
                    423: }
                    424: 
                    425: /* Output the name of type TYPE, with no punctuation.
                    426:    Such names can be set up either by typedef declarations
                    427:    or by struct, enum and union tags.  */
                    428: 
                    429: static void
                    430: dbxout_type_name (type)
                    431:      register tree type;
                    432: {
                    433:   register char *name;
                    434:   if (TYPE_NAME (type) == 0)
                    435:     abort ();
                    436:   if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
                    437:     name = IDENTIFIER_POINTER (TYPE_NAME (type));
                    438:   else if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL)
                    439:     name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
                    440:   else
                    441:     abort ();
                    442: 
                    443:   fprintf (asmfile, "%s", name);
                    444:   CHARS (strlen (name));
                    445: }
                    446: 
                    447: /* Output a .stabs for the symbol defined by DECL,
                    448:    which must be a ..._DECL node in the normal namespace.
                    449:    It may be a CONST_DECL, a FUNCTION_DECL, a PARM_DECL or a VAR_DECL.
                    450:    LOCAL is nonzero if the scope is less than the entire file.  */
                    451: 
                    452: void
                    453: dbxout_symbol (decl, local)
                    454:      tree decl;
                    455:      int local;
                    456: {
1.1.1.2 ! root      457:   int letter = 0;
        !           458:   tree type = TREE_TYPE (decl);
1.1       root      459: 
                    460:   /* If global, first output all types and all
                    461:      struct, enum and union tags that have been created
                    462:      and not yet output.  */
                    463: 
                    464:   if (local == 0)
                    465:     {
                    466:       dbxout_tags (gettags ());
                    467:       dbxout_types (get_permanent_types ());
                    468:     }
                    469: 
1.1.1.2 ! root      470:   /* If the decl lacks rtl representation, avoid fault below.  */
        !           471: 
        !           472:   if (DECL_RTL (decl) == 0)
        !           473:     return;
        !           474: 
1.1       root      475:   current_sym_code = 0;
                    476:   current_sym_value = 0;
                    477:   current_sym_addr = 0;
                    478: 
                    479:   /* The output will always start with the symbol name,
                    480:      so count that always in the length-output-so-far.  */
                    481: 
                    482:   current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (decl)));
                    483: 
                    484:   switch (TREE_CODE (decl))
                    485:     {
                    486:     case CONST_DECL:
                    487:       /* Enum values are defined by defining the enum type.  */
                    488:       break;
                    489: 
                    490:     case FUNCTION_DECL:
                    491:       if (TREE_EXTERNAL (decl))
                    492:        break;
                    493:       if (GET_CODE (DECL_RTL (decl)) != MEM
                    494:          || GET_CODE (XEXP (DECL_RTL (decl), 0)) != SYMBOL_REF)
                    495:        break;
                    496:       fprintf (asmfile, ".stabs \"%s:%c",
                    497:               IDENTIFIER_POINTER (DECL_NAME (decl)),
                    498:               TREE_PUBLIC (decl) ? 'F' : 'f');
                    499: 
                    500:       current_sym_code = N_FUN;
                    501:       current_sym_addr = XEXP (DECL_RTL (decl), 0);
                    502: 
                    503:       if (TREE_TYPE (TREE_TYPE (decl)))
                    504:        dbxout_type (TREE_TYPE (TREE_TYPE (decl)), 0);
                    505:       else
                    506:        dbxout_type (void_type_node, 0);
                    507:       dbxout_finish_symbol ();
                    508:       break;
                    509: 
                    510:     case TYPE_DECL:
                    511:       /* Output typedef name.  */
                    512:       fprintf (asmfile, ".stabs \"%s:t",
                    513:               IDENTIFIER_POINTER (DECL_NAME (decl)));
                    514: 
                    515:       current_sym_code = N_LSYM;
                    516: 
                    517:       dbxout_type (TREE_TYPE (decl), 0);
                    518:       dbxout_finish_symbol ();
                    519:       break;
                    520:       
                    521:     case PARM_DECL:
                    522:       /* Parm decls go in their own separate chains
                    523:         and are output by dbxout_reg_parms and dbxout_parms.  */
                    524:       abort ();
                    525: 
                    526:     case VAR_DECL:
                    527:       /* Don't mention a variable that is external.
                    528:         Let the file that defines it describe it.  */
                    529:       if (TREE_EXTERNAL (decl))
                    530:        break;
                    531: 
                    532:       /* Don't mention a variable at all
                    533:         if it was completely optimized into nothingness.  */
                    534:       if (GET_CODE (DECL_RTL (decl)) == REG
1.1.1.2 ! root      535:          && (REGNO (DECL_RTL (decl)) < 0
        !           536:              || REGNO (DECL_RTL (decl)) >= FIRST_PSEUDO_REGISTER))
1.1       root      537:        break;
                    538: 
                    539:       /* Ok, start a symtab entry and output the variable name.  */
                    540:       fprintf (asmfile, ".stabs \"%s:",
                    541:               IDENTIFIER_POINTER (DECL_NAME (decl)));
1.1.1.2 ! root      542: 
1.1       root      543:       /* The kind-of-variable letter depends on where
                    544:         the variable is and on the scope of its name:
                    545:         G and N_GSYM for static storage and global scope,
                    546:         S for static storage and file scope,
                    547:         v for static storage and local scope,
                    548:            for those two, use N_LCSYM if data is in bss segment,
                    549:            N_STSYM if it is in data segment, or N_FUN if in text segment.
                    550:         no letter at all, and N_LSYM, for auto variable,
                    551:         r and N_RSYM for register variable.  */
                    552: 
                    553:       if (GET_CODE (DECL_RTL (decl)) == MEM
                    554:          && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
                    555:        {
                    556:          if (TREE_PUBLIC (decl))
                    557:            {
                    558:              letter = 'G';
                    559:              current_sym_code = N_GSYM;
                    560:            }
                    561:          else
                    562:            {
                    563:              current_sym_addr = XEXP (DECL_RTL (decl), 0);
                    564: 
                    565:              letter = TREE_PERMANENT (decl) ? 'S' : 'v';
                    566: 
                    567:              if (!DECL_INITIAL (decl))
                    568:                current_sym_code = N_LCSYM;
                    569:              else if (TREE_READONLY (decl) && ! TREE_VOLATILE (decl))
                    570:                /* This is not quite right, but it's the closest
                    571:                   of all the codes that Unix defines.  */
                    572:                current_sym_code = N_FUN;
                    573:              else
                    574:                current_sym_code = N_STSYM;
                    575:            }
                    576:        }
1.1.1.2 ! root      577:       else if (GET_CODE (DECL_RTL (decl)) == REG)
        !           578:        {
        !           579:          letter = 'r';
        !           580:          current_sym_code = N_RSYM;
        !           581:          current_sym_value = DBX_REGISTER_NUMBER (REGNO (DECL_RTL (decl)));
        !           582:        }
        !           583:       else if (GET_CODE (DECL_RTL (decl)) == MEM
        !           584:               && (GET_CODE (XEXP (DECL_RTL (decl), 0)) == MEM
        !           585:                   || (GET_CODE (XEXP (DECL_RTL (decl), 0)) == REG
        !           586:                       && REGNO (XEXP (DECL_RTL (decl), 0)) != FRAME_POINTER_REGNUM)))
        !           587:        /* If the value is indirect by memory or by a register
        !           588:           that isn't the frame pointer
        !           589:           then it means the object is variable-sized and address through
        !           590:           that register or stack slot.  DBX has no way to represent this
        !           591:           so all we can do is output the variable as a pointer.  */
1.1       root      592:        {
1.1.1.2 ! root      593:          if (GET_CODE (XEXP (DECL_RTL (decl), 0)) == REG)
1.1       root      594:            {
                    595:              letter = 'r';
                    596:              current_sym_code = N_RSYM;
1.1.1.2 ! root      597:              current_sym_value = DBX_REGISTER_NUMBER (REGNO (XEXP (DECL_RTL (decl), 0)));
1.1       root      598:            }
                    599:          else
                    600:            {
                    601:              current_sym_code = N_LSYM;
1.1.1.2 ! root      602:              /* DECL_RTL looks like (MEM (MEM (PLUS (REG...) (CONST_INT...)))).
1.1       root      603:                 We want the value of that CONST_INT.  */
1.1.1.2 ! root      604:              current_sym_value = INTVAL (XEXP (XEXP (XEXP (DECL_RTL (decl), 0), 0), 1));
1.1       root      605:            }
1.1.1.2 ! root      606: 
        !           607:          type = build_pointer_type (TREE_TYPE (decl));
1.1       root      608:        }
1.1.1.2 ! root      609:       else if (GET_CODE (DECL_RTL (decl)) == MEM
        !           610:               && XEXP (DECL_RTL (decl), 0) != const0_rtx)
        !           611:        /* const0_rtx is used as the address for a variable that
        !           612:           is a dummy due to an erroneous declaration.
        !           613:           Ignore such vars.  */
        !           614:        {
        !           615:          current_sym_code = N_LSYM;
        !           616:          if (GET_CODE (XEXP (DECL_RTL (decl), 0)) == REG)
        !           617:            current_sym_value = 0;
        !           618:          else
        !           619:            /* DECL_RTL looks like (MEM (PLUS (REG...) (CONST_INT...)))
        !           620:               We want the value of that CONST_INT.  */
        !           621:            current_sym_value = INTVAL (XEXP (XEXP (DECL_RTL (decl), 0), 1));
        !           622:        }
        !           623:       if (letter) putc (letter, asmfile);
        !           624:       dbxout_type (type, 0);
        !           625:       dbxout_finish_symbol ();
1.1       root      626:       break;
                    627:     }
                    628: }
                    629: 
                    630: static void
                    631: dbxout_finish_symbol ()
                    632: {
                    633:   fprintf (asmfile, "\",%d,0,0,", current_sym_code);
                    634:   if (current_sym_addr)
                    635:     output_addr_const (asmfile, current_sym_addr);
                    636:   else
                    637:     fprintf (asmfile, "%d", current_sym_value);
                    638:   putc ('\n', asmfile);
                    639: }
                    640: 
                    641: /* Output definitions of all the decls in a chain.  */
                    642: 
                    643: static void
                    644: dbxout_syms (syms)
                    645:      tree syms;
                    646: {
                    647:   while (syms)
                    648:     {
                    649:       dbxout_symbol (syms, 1);
                    650:       syms = TREE_CHAIN (syms);
                    651:     }
                    652: }
                    653: 
                    654: /* The following two functions output definitions of function parameters.
                    655:    Each parameter gets a definition locating it in the parameter list.
                    656:    Each parameter that is a register variable gets a second definition
                    657:    locating it in the register.
                    658: 
                    659:    Printing or argument lists in gdb uses the definitions that
                    660:    locate in the parameter list.  But reference to the variable in
                    661:    expressions uses preferentially the definition as a register.  */
                    662: 
                    663: /* Output definitions, referring to storage in the parmlist,
                    664:    of all the parms in PARMS, which is a chain of PARM_DECL nodes.  */
                    665: 
                    666: static void
                    667: dbxout_parms (parms)
                    668:      tree parms;
                    669: {
                    670:   for (; parms; parms = TREE_CHAIN (parms))
                    671:     {
1.1.1.2 ! root      672:       if (DECL_OFFSET (parms) >= 0)
        !           673:        {
        !           674:          current_sym_code = N_PSYM;
        !           675:          current_sym_value = DECL_OFFSET (parms) / BITS_PER_UNIT;
        !           676:          current_sym_addr = 0;
        !           677:          current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           678: 
        !           679:          fprintf (asmfile, ".stabs \"%s:p",
        !           680:                   IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           681: 
        !           682:          if (GET_CODE (DECL_RTL (parms)) == REG
        !           683:              && REGNO (DECL_RTL (parms)) >= 0
        !           684:              && REGNO (DECL_RTL (parms)) < FIRST_PSEUDO_REGISTER)
        !           685:            dbxout_type (DECL_ARG_TYPE (parms), 0);
        !           686:          else
        !           687:            {
        !           688:              /* This is the case where the parm is passed as an int or double
        !           689:                 and it is converted to a char, short or float and stored back
        !           690:                 in the parmlist.  In this case, describe the parm
        !           691:                 with the variable's declared type, and adjust the address
        !           692:                 if the least significant bytes (which we are using) are not
        !           693:                 the first ones.  */
1.1       root      694: #ifdef BYTES_BIG_ENDIAN
1.1.1.2 ! root      695:              if (TREE_TYPE (parms) != DECL_ARG_TYPE (parms))
        !           696:                current_sym_value += (GET_MODE_SIZE (TYPE_MODE (DECL_ARG_TYPE (parms)))
        !           697:                                      - GET_MODE_SIZE (GET_MODE (DECL_RTL (parms))));
1.1       root      698: #endif
                    699: 
1.1.1.2 ! root      700:              if (GET_CODE (DECL_RTL (parms)) == MEM
        !           701:                  && GET_CODE (XEXP (DECL_RTL (parms), 0)) == PLUS
        !           702:                  && GET_CODE (XEXP (XEXP (DECL_RTL (parms), 0), 1)) == CONST_INT
        !           703:                  && INTVAL (XEXP (XEXP (DECL_RTL (parms), 0), 1)) == current_sym_value)
        !           704:                dbxout_type (TREE_TYPE (parms), 0);
        !           705:              else
        !           706:                {
        !           707:                  current_sym_value = DECL_OFFSET (parms) / BITS_PER_UNIT;
        !           708:                  dbxout_type (DECL_ARG_TYPE (parms), 0);
        !           709:                }
        !           710:            }
        !           711:          dbxout_finish_symbol ();
        !           712:        }
        !           713:       /* Parm was passed in registers.
        !           714:         If it is in a register, output a "regparm" symbol
        !           715:         for the register it lives in.  */
        !           716:       else if (GET_CODE (DECL_RTL (parms)) == REG)
        !           717:        {
        !           718:          current_sym_code = N_RSYM;
        !           719:          current_sym_value = DBX_REGISTER_NUMBER (REGNO (DECL_RTL (parms)));
        !           720:          current_sym_addr = 0;
        !           721:          current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           722: 
        !           723:          fprintf (asmfile, ".stabs \"%s:P",
        !           724:                   IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           725: 
        !           726:          dbxout_type (DECL_ARG_TYPE (parms), 0);
        !           727:          dbxout_finish_symbol ();
        !           728:        }
        !           729:       else if (GET_CODE (DECL_RTL (parms)) == MEM
        !           730:               && XEXP (DECL_RTL (parms), 0) != const0_rtx)
        !           731:        {
        !           732:          current_sym_code = N_LSYM;
        !           733:          /* DECL_RTL looks like (MEM (PLUS (REG...) (CONST_INT...))).
        !           734:             We want the value of that CONST_INT.  */
        !           735:          current_sym_value = INTVAL (XEXP (XEXP (DECL_RTL (parms), 0), 1));
        !           736:          current_sym_addr = 0;
        !           737:          current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           738: 
        !           739:          fprintf (asmfile, ".stabs \"%s:p",
        !           740:                   IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           741: 
        !           742:          /* This is the case where the parm is passed as an int or double
        !           743:             and it is converted to a char, short or float and stored back
        !           744:             in the parmlist.  In this case, describe the parm
        !           745:             with the variable's declared type, and adjust the address
        !           746:             if the least significant bytes (which we are using) are not
        !           747:             the first ones.  */
        !           748: #ifdef BYTES_BIG_ENDIAN
        !           749:          if (TREE_TYPE (parms) != DECL_ARG_TYPE (parms))
        !           750:            current_sym_value += (GET_MODE_SIZE (TYPE_MODE (DECL_ARG_TYPE (parms)))
        !           751:                                  - GET_MODE_SIZE (GET_MODE (DECL_RTL (parms))));
        !           752: #endif
        !           753: 
        !           754:          dbxout_type (TREE_TYPE (parms), 0);
        !           755:          dbxout_finish_symbol ();
        !           756:        }
        !           757: 
1.1       root      758:     }
                    759: }
                    760: 
                    761: /* Output definitions, referring to registers,
                    762:    of all the parms in PARMS which are stored in registers during the function.
                    763:    PARMS is a chain of PARM_DECL nodes.  */
                    764: 
                    765: static void
                    766: dbxout_reg_parms (parms)
                    767:      tree parms;
                    768: {
                    769:   while (parms)
                    770:     {
1.1.1.2 ! root      771:       /* Report parms that live in registers during the function.  */
1.1       root      772:       if (GET_CODE (DECL_RTL (parms)) == REG
1.1.1.2 ! root      773:          && REGNO (DECL_RTL (parms)) >= 0
        !           774:          && REGNO (DECL_RTL (parms)) < FIRST_PSEUDO_REGISTER
        !           775:          && DECL_OFFSET (parms) >= 0)
1.1       root      776:        {
                    777:          current_sym_code = N_RSYM;
                    778:          current_sym_value = DBX_REGISTER_NUMBER (REGNO (DECL_RTL (parms)));
                    779:          current_sym_addr = 0;
                    780:          current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (parms)));
                    781:          fprintf (asmfile, ".stabs \"%s:r",
                    782:                   IDENTIFIER_POINTER (DECL_NAME (parms)));
                    783:          dbxout_type (TREE_TYPE (parms), 0);
                    784:          dbxout_finish_symbol ();
                    785:        }
1.1.1.2 ! root      786:       /* Report parms that live in memory but outside the parmlist.  */
        !           787:       else if (GET_CODE (DECL_RTL (parms)) == MEM
        !           788:               && GET_CODE (XEXP (DECL_RTL (parms), 0)) == PLUS
        !           789:               && GET_CODE (XEXP (XEXP (DECL_RTL (parms), 0), 1)) == CONST_INT)
        !           790:        {
        !           791:          int offset = DECL_OFFSET (parms) / BITS_PER_UNIT;
        !           792:          /* A parm declared char is really passed as an int,
        !           793:             so it occupies the least significant bytes.
        !           794:             On a big-endian machine those are not the low-numbered ones.  */
        !           795: #ifdef BYTES_BIG_ENDIAN
        !           796:          if (offset != -1 && TREE_TYPE (parms) != DECL_ARG_TYPE (parms))
        !           797:            offset += (GET_MODE_SIZE (TYPE_MODE (DECL_ARG_TYPE (parms)))
        !           798:                       - GET_MODE_SIZE (GET_MODE (DECL_RTL (parms))));
        !           799: #endif
        !           800:          if (INTVAL (XEXP (XEXP (DECL_RTL (parms), 0), 1)) != offset)
        !           801:            {
        !           802:              current_sym_code = N_LSYM;
        !           803:              current_sym_value = INTVAL (XEXP (XEXP (DECL_RTL (parms), 0), 1));
        !           804:              current_sym_addr = 0;
        !           805:              current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           806:              fprintf (asmfile, ".stabs \"%s:",
        !           807:                       IDENTIFIER_POINTER (DECL_NAME (parms)));
        !           808:              dbxout_type (TREE_TYPE (parms), 0);
        !           809:              dbxout_finish_symbol ();
        !           810:            }
        !           811:        }
1.1       root      812:       parms = TREE_CHAIN (parms);
                    813:     }
                    814: }
                    815: 
                    816: /* Given a chain of ..._TYPE nodes, all of which have names,
                    817:    output definitions of those names, as typedefs.  */
                    818: 
                    819: void
                    820: dbxout_types (types)
                    821:      register tree types;
                    822: {
                    823:   while (types)
                    824:     {
                    825:       if (TYPE_NAME (types)
                    826:          && TREE_CODE (TYPE_NAME (types)) == TYPE_DECL)
                    827:        dbxout_type_def (types);
                    828:       types = TREE_CHAIN (types);
                    829:     }
                    830: }
                    831: 
                    832: /* Output a definition of a typedef name.
1.1.1.2 ! root      833:    It works much like any other kind of symbol definition.
        !           834:    Output nothing if TYPE's definition has been output already.  */
1.1       root      835: 
                    836: static void
                    837: dbxout_type_def (type)
                    838:      tree type;
                    839: {
1.1.1.2 ! root      840: #if 0  /* Incorrect; causes some type NAMES not to be defined,
        !           841:          whose TYPES were defined already.  */
        !           842:   if (TYPE_SYMTAB_ADDRESS (type) != 0
        !           843:       && typevec[TYPE_SYMTAB_ADDRESS (type)] == TYPE_DEFINED)
        !           844:     return;
        !           845: #endif
        !           846: 
1.1       root      847:   current_sym_code = N_LSYM;
                    848:   current_sym_value = 0;
                    849:   current_sym_addr = 0;
                    850:   current_sym_nchars = 0;
                    851:   current_sym_nchars
                    852:     = 2 + strlen (IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
                    853: 
                    854:   fprintf (asmfile, ".stabs \"%s:t",
                    855:           IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
                    856:   dbxout_type (type, 1);
                    857:   dbxout_finish_symbol ();
                    858: }
                    859: 
                    860: /* Output the tags (struct, union and enum definitions with names) for a block,
                    861:    given a list of them (a chain of TREE_LIST nodes) in TAGS.
                    862:    We must check to include those that have been mentioned already with
                    863:    only a cross-reference.  */
                    864: 
                    865: void
                    866: dbxout_tags (tags)
                    867:      tree tags;
                    868: {
                    869:   register tree link;
                    870:   for (link = tags; link; link = TREE_CHAIN (link))
                    871:     {
1.1.1.2 ! root      872:       register tree type = TYPE_MAIN_VARIANT (TREE_VALUE (link));
1.1       root      873:       if (TREE_PURPOSE (link) != 0
1.1.1.2 ! root      874:          && ! TREE_ASM_WRITTEN (link)
1.1       root      875:          && TYPE_SIZE (type) != 0)
                    876:        {
1.1.1.2 ! root      877:          TREE_ASM_WRITTEN (link) = 1;
1.1       root      878:          current_sym_code = N_LSYM;
                    879:          current_sym_value = 0;
                    880:          current_sym_addr = 0;
                    881:          current_sym_nchars = 2 + strlen (IDENTIFIER_POINTER (TREE_PURPOSE (link)));
                    882: 
                    883:          fprintf (asmfile, ".stabs \"%s:T",
                    884:                   IDENTIFIER_POINTER (TREE_PURPOSE (link)));
                    885:          dbxout_type (type, 1);
                    886:          dbxout_finish_symbol ();
                    887:        }
                    888:     }
                    889: }
                    890: 
                    891: /* Output everything about a symbol block (that is to say, a LET_STMT node
                    892:    that represents a scope level),
                    893:    including recursive output of contained blocks.
                    894: 
                    895:    STMT is the LET_STMT node.
                    896:    DEPTH is its depth within containing symbol blocks.
                    897:    ARGS is usually zero; but for the outermost block of the
                    898:    body of a function, it is a chain of PARM_DECLs for the function parameters.
                    899:    We output definitions of all the register parms
                    900:    as if they were local variables of that block.
                    901: 
                    902:    Actually, STMT may be several statements chained together.
                    903:    We handle them all in sequence.  */
                    904: 
                    905: static void
                    906: dbxout_block (stmt, depth, args)
                    907:      register tree stmt;
                    908:      int depth;
1.1.1.2 ! root      909:      tree args;
1.1       root      910: {
                    911:   int blocknum;
                    912: 
                    913:   while (stmt)
                    914:     {
                    915:       switch (TREE_CODE (stmt))
                    916:        {
                    917:        case COMPOUND_STMT:
                    918:        case LOOP_STMT:
                    919:          dbxout_block (STMT_BODY (stmt), depth, 0);
                    920:          break;
                    921: 
                    922:        case IF_STMT:
                    923:          dbxout_block (STMT_THEN (stmt), depth, 0);
                    924:          dbxout_block (STMT_ELSE (stmt), depth, 0);
                    925:          break;
                    926: 
                    927:        case LET_STMT:
                    928:          /* In dbx format, the syms of a block come before the N_LBRAC.  */
                    929:          dbxout_tags (STMT_TYPE_TAGS (stmt));
1.1.1.2 ! root      930:          dbxout_syms (STMT_VARS (stmt));
1.1       root      931:          if (args)
                    932:            dbxout_reg_parms (args);
                    933: 
                    934:          /* Now output an N_LBRAC symbol to represent the beginning of
                    935:             the block.  Use the block's tree-walk order to generate
                    936:             the assembler symbols LBBn and LBEn
                    937:             that final will define around the code in this block.  */
                    938:          if (depth > 0)
                    939:            {
                    940:              blocknum = next_block_number++;
                    941:              fprintf (asmfile, ".stabn %d,0,0,LBB%d\n", N_LBRAC, blocknum);
                    942:            }
                    943: 
                    944:          /* Output the interior of the block.  */
                    945:          dbxout_block (STMT_BODY (stmt), depth + 1, 0);
                    946: 
                    947:          /* Refer to the marker for the end of the block.  */
                    948:          if (depth > 0)
                    949:            fprintf (asmfile, ".stabn %d,0,0,LBE%d\n", N_RBRAC, blocknum);
                    950:        }
                    951:       stmt = TREE_CHAIN (stmt);
                    952:     }
                    953: }
                    954: 
                    955: /* Output dbx data for a function definition.
                    956:    This includes a definition of the function name itself (a symbol),
                    957:    definitions of the parameters (locating them in the parameter list)
                    958:    and then output the block that makes up the function's body
                    959:    (including all the auto variables of the function).  */
                    960: 
                    961: void
                    962: dbxout_function (decl)
                    963:      tree decl;
                    964: {
                    965:   dbxout_symbol (decl, 0);
                    966:   dbxout_parms (DECL_ARGUMENTS (decl));
                    967:   dbxout_block (DECL_INITIAL (decl), 0, DECL_ARGUMENTS (decl));
                    968: }
1.1.1.2 ! root      969: 
        !           970: #else /* NO_DBX_FORMAT */
        !           971: 
        !           972: void
        !           973: dbxout_init (asm_file, input_file_name)
        !           974:      FILE *asm_file;
        !           975:      char *input_file_name;
        !           976: {}
        !           977: 
        !           978: void
        !           979: dbxout_symbol (decl, local)
        !           980:      tree decl;
        !           981:      int local;
        !           982: {}
        !           983: 
        !           984: void
        !           985: dbxout_types (types)
        !           986:      register tree types;
        !           987: {}
        !           988: 
        !           989: void
        !           990: dbxout_tags (tags)
        !           991:      tree tags;
        !           992: {}
        !           993: 
        !           994: void
        !           995: dbxout_function (decl)
        !           996:      tree decl;
        !           997: {}
        !           998: 
        !           999: #endif /* NO_DBX_FORMAT */

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