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binutils-gdb/gas/symbols.c

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19990502 sourceware import
1999-05-03 15:29:11 +08:00
/* symbols.c -symbol table-
Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 97, 1998
Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
/* #define DEBUG_SYMS / * to debug symbol list maintenance */
#include <ctype.h>
#include "as.h"
#include "obstack.h" /* For "symbols.h" */
#include "subsegs.h"
/* This is non-zero if symbols are case sensitive, which is the
default. */
int symbols_case_sensitive = 1;
#ifndef WORKING_DOT_WORD
extern int new_broken_words;
#endif
/* symbol-name => struct symbol pointer */
static struct hash_control *sy_hash;
/* Below are commented in "symbols.h". */
symbolS *symbol_rootP;
symbolS *symbol_lastP;
symbolS abs_symbol;
#ifdef DEBUG_SYMS
#define debug_verify_symchain verify_symbol_chain
#else
#define debug_verify_symchain(root, last) ((void) 0)
#endif
struct obstack notes;
static void fb_label_init PARAMS ((void));
static long dollar_label_instance PARAMS ((long));
static long fb_label_instance PARAMS ((long));
static void print_binary PARAMS ((FILE *, const char *, expressionS *));
/* symbol_new()
Return a pointer to a new symbol. Die if we can't make a new
symbol. Fill in the symbol's values. Add symbol to end of symbol
chain.
This function should be called in the general case of creating a
symbol. However, if the output file symbol table has already been
set, and you are certain that this symbol won't be wanted in the
output file, you can call symbol_create. */
symbolS *
symbol_new (name, segment, valu, frag)
const char *name;
segT segment;
valueT valu;
fragS *frag;
{
symbolS *symbolP = symbol_create (name, segment, valu, frag);
/*
* Link to end of symbol chain.
*/
#ifdef BFD_ASSEMBLER
{
extern int symbol_table_frozen;
if (symbol_table_frozen)
abort ();
}
#endif
symbol_append (symbolP, symbol_lastP, &symbol_rootP, &symbol_lastP);
return symbolP;
}
symbolS *
symbol_create (name, segment, valu, frag)
const char *name; /* It is copied, the caller can destroy/modify */
segT segment; /* Segment identifier (SEG_<something>) */
valueT valu; /* Symbol value */
fragS *frag; /* Associated fragment */
{
unsigned int name_length;
char *preserved_copy_of_name;
symbolS *symbolP;
name_length = strlen (name) + 1; /* +1 for \0 */
obstack_grow (&notes, name, name_length);
preserved_copy_of_name = obstack_finish (&notes);
#ifdef STRIP_UNDERSCORE
if (preserved_copy_of_name[0] == '_')
preserved_copy_of_name++;
#endif
#ifdef tc_canonicalize_symbol_name
preserved_copy_of_name =
tc_canonicalize_symbol_name (preserved_copy_of_name);
#endif
if (! symbols_case_sensitive)
{
unsigned char *s;
for (s = (unsigned char *) preserved_copy_of_name; *s != '\0'; s++)
if (islower (*s))
*s = toupper (*s);
}
symbolP = (symbolS *) obstack_alloc (&notes, sizeof (symbolS));
/* symbol must be born in some fixed state. This seems as good as any. */
memset (symbolP, 0, sizeof (symbolS));
#ifdef BFD_ASSEMBLER
symbolP->bsym = bfd_make_empty_symbol (stdoutput);
if (symbolP->bsym == NULL)
as_perror ("%s", "bfd_make_empty_symbol");
symbolP->bsym->udata.p = (PTR) symbolP;
#endif
S_SET_NAME (symbolP, preserved_copy_of_name);
S_SET_SEGMENT (symbolP, segment);
S_SET_VALUE (symbolP, valu);
symbol_clear_list_pointers (symbolP);
symbolP->sy_frag = frag;
#ifndef BFD_ASSEMBLER
symbolP->sy_number = ~0;
symbolP->sy_name_offset = (unsigned int) ~0;
#endif
obj_symbol_new_hook (symbolP);
#ifdef tc_symbol_new_hook
tc_symbol_new_hook (symbolP);
#endif
return symbolP;
}
/*
* colon()
*
* We have just seen "<name>:".
* Creates a struct symbol unless it already exists.
*
* Gripes if we are redefining a symbol incompatibly (and ignores it).
*
*/
symbolS *
colon (sym_name) /* just seen "x:" - rattle symbols & frags */
const char *sym_name; /* symbol name, as a cannonical string */
/* We copy this string: OK to alter later. */
{
register symbolS *symbolP; /* symbol we are working with */
/* Sun local labels go out of scope whenever a non-local symbol is
defined. */
if (LOCAL_LABELS_DOLLAR)
{
int local;
#ifdef BFD_ASSEMBLER
local = bfd_is_local_label_name (stdoutput, sym_name);
#else
local = LOCAL_LABEL (sym_name);
#endif
if (! local)
dollar_label_clear ();
}
#ifndef WORKING_DOT_WORD
if (new_broken_words)
{
struct broken_word *a;
int possible_bytes;
fragS *frag_tmp;
char *frag_opcode;
extern const int md_short_jump_size;
extern const int md_long_jump_size;
possible_bytes = (md_short_jump_size
+ new_broken_words * md_long_jump_size);
frag_tmp = frag_now;
frag_opcode = frag_var (rs_broken_word,
possible_bytes,
possible_bytes,
(relax_substateT) 0,
(symbolS *) broken_words,
(offsetT) 0,
NULL);
/* We want to store the pointer to where to insert the jump table in the
fr_opcode of the rs_broken_word frag. This requires a little
hackery. */
while (frag_tmp
&& (frag_tmp->fr_type != rs_broken_word
|| frag_tmp->fr_opcode))
frag_tmp = frag_tmp->fr_next;
know (frag_tmp);
frag_tmp->fr_opcode = frag_opcode;
new_broken_words = 0;
for (a = broken_words; a && a->dispfrag == 0; a = a->next_broken_word)
a->dispfrag = frag_tmp;
}
#endif /* WORKING_DOT_WORD */
if ((symbolP = symbol_find (sym_name)) != 0)
{
#ifdef RESOLVE_SYMBOL_REDEFINITION
if (RESOLVE_SYMBOL_REDEFINITION (symbolP))
return symbolP;
#endif
/*
* Now check for undefined symbols
*/
if (!S_IS_DEFINED (symbolP) || S_IS_COMMON (symbolP))
{
if (S_GET_VALUE (symbolP) == 0)
{
symbolP->sy_frag = frag_now;
#ifdef OBJ_VMS
S_SET_OTHER(symbolP, const_flag);
#endif
S_SET_VALUE (symbolP, (valueT) frag_now_fix ());
S_SET_SEGMENT (symbolP, now_seg);
#ifdef N_UNDF
know (N_UNDF == 0);
#endif /* if we have one, it better be zero. */
}
else
{
/*
* There are still several cases to check:
* A .comm/.lcomm symbol being redefined as
* initialized data is OK
* A .comm/.lcomm symbol being redefined with
* a larger size is also OK
*
* This only used to be allowed on VMS gas, but Sun cc
* on the sparc also depends on it.
*/
if (((!S_IS_DEBUG (symbolP)
&& (!S_IS_DEFINED (symbolP) || S_IS_COMMON (symbolP))
&& S_IS_EXTERNAL (symbolP))
|| S_GET_SEGMENT (symbolP) == bss_section)
&& (now_seg == data_section
|| now_seg == S_GET_SEGMENT (symbolP)))
{
/*
* Select which of the 2 cases this is
*/
if (now_seg != data_section)
{
/*
* New .comm for prev .comm symbol.
* If the new size is larger we just
* change its value. If the new size
* is smaller, we ignore this symbol
*/
if (S_GET_VALUE (symbolP)
< ((unsigned) frag_now_fix ()))
{
S_SET_VALUE (symbolP, (valueT) frag_now_fix ());
}
}
else
{
/* It is a .comm/.lcomm being converted to initialized
data. */
symbolP->sy_frag = frag_now;
#ifdef OBJ_VMS
S_SET_OTHER(symbolP, const_flag);
#endif
S_SET_VALUE (symbolP, (valueT) frag_now_fix ());
S_SET_SEGMENT (symbolP, now_seg); /* keep N_EXT bit */
}
}
else
{
#if defined (S_GET_OTHER) && defined (S_GET_DESC)
as_fatal (_("Symbol \"%s\" is already defined as \"%s\"/%d.%d.%ld."),
sym_name,
segment_name (S_GET_SEGMENT (symbolP)),
S_GET_OTHER (symbolP), S_GET_DESC (symbolP),
(long) S_GET_VALUE (symbolP));
#else
as_fatal (_("Symbol \"%s\" is already defined as \"%s\"/%ld."),
sym_name,
segment_name (S_GET_SEGMENT (symbolP)),
(long) S_GET_VALUE (symbolP));
#endif
}
} /* if the undefined symbol has no value */
}
else
{
/* Don't blow up if the definition is the same */
if (!(frag_now == symbolP->sy_frag
&& S_GET_VALUE (symbolP) == frag_now_fix ()
&& S_GET_SEGMENT (symbolP) == now_seg))
as_fatal (_("Symbol %s already defined."), sym_name);
} /* if this symbol is not yet defined */
}
else
{
symbolP = symbol_new (sym_name, now_seg, (valueT) frag_now_fix (),
frag_now);
#ifdef OBJ_VMS
S_SET_OTHER (symbolP, const_flag);
#endif /* OBJ_VMS */
symbol_table_insert (symbolP);
} /* if we have seen this symbol before */
if (mri_common_symbol != NULL)
{
/* This symbol is actually being defined within an MRI common
section. This requires special handling. */
symbolP->sy_value.X_op = O_symbol;
symbolP->sy_value.X_add_symbol = mri_common_symbol;
symbolP->sy_value.X_add_number = S_GET_VALUE (mri_common_symbol);
symbolP->sy_frag = &zero_address_frag;
S_SET_SEGMENT (symbolP, expr_section);
symbolP->sy_mri_common = 1;
}
#ifdef tc_frob_label
tc_frob_label (symbolP);
#endif
#ifdef obj_frob_label
obj_frob_label (symbolP);
#endif
return symbolP;
}
/*
* symbol_table_insert()
*
* Die if we can't insert the symbol.
*
*/
void
symbol_table_insert (symbolP)
symbolS *symbolP;
{
register const char *error_string;
know (symbolP);
know (S_GET_NAME (symbolP));
if ((error_string = hash_jam (sy_hash, S_GET_NAME (symbolP), (PTR) symbolP)))
{
as_fatal (_("Inserting \"%s\" into symbol table failed: %s"),
S_GET_NAME (symbolP), error_string);
} /* on error */
} /* symbol_table_insert() */
/*
* symbol_find_or_make()
*
* If a symbol name does not exist, create it as undefined, and insert
* it into the symbol table. Return a pointer to it.
*/
symbolS *
symbol_find_or_make (name)
const char *name;
{
register symbolS *symbolP;
symbolP = symbol_find (name);
if (symbolP == NULL)
{
symbolP = symbol_make (name);
symbol_table_insert (symbolP);
} /* if symbol wasn't found */
return (symbolP);
} /* symbol_find_or_make() */
symbolS *
symbol_make (name)
CONST char *name;
{
symbolS *symbolP;
/* Let the machine description default it, e.g. for register names. */
symbolP = md_undefined_symbol ((char *) name);
if (!symbolP)
symbolP = symbol_new (name, undefined_section, (valueT) 0, &zero_address_frag);
return (symbolP);
} /* symbol_make() */
/*
* symbol_find()
*
* Implement symbol table lookup.
* In: A symbol's name as a string: '\0' can't be part of a symbol name.
* Out: NULL if the name was not in the symbol table, else the address
* of a struct symbol associated with that name.
*/
symbolS *
symbol_find (name)
CONST char *name;
{
#ifdef STRIP_UNDERSCORE
return (symbol_find_base (name, 1));
#else /* STRIP_UNDERSCORE */
return (symbol_find_base (name, 0));
#endif /* STRIP_UNDERSCORE */
} /* symbol_find() */
symbolS *
symbol_find_base (name, strip_underscore)
CONST char *name;
int strip_underscore;
{
if (strip_underscore && *name == '_')
name++;
#ifdef tc_canonicalize_symbol_name
{
char *copy;
copy = (char *) alloca (strlen (name) + 1);
strcpy (copy, name);
name = tc_canonicalize_symbol_name (copy);
}
#endif
if (! symbols_case_sensitive)
{
unsigned char *copy;
copy = (unsigned char *) alloca (strlen (name) + 1);
strcpy (copy, name);
name = (const char *) copy;
for (; *copy != '\0'; copy++)
if (islower (*copy))
*copy = toupper (*copy);
}
return ((symbolS *) hash_find (sy_hash, name));
}
/*
* Once upon a time, symbols were kept in a singly linked list. At
* least coff needs to be able to rearrange them from time to time, for
* which a doubly linked list is much more convenient. Loic did these
* as macros which seemed dangerous to me so they're now functions.
* xoxorich.
*/
/* Link symbol ADDME after symbol TARGET in the chain. */
void
symbol_append (addme, target, rootPP, lastPP)
symbolS *addme;
symbolS *target;
symbolS **rootPP;
symbolS **lastPP;
{
if (target == NULL)
{
know (*rootPP == NULL);
know (*lastPP == NULL);
addme->sy_next = NULL;
#ifdef SYMBOLS_NEED_BACKPOINTERS
addme->sy_previous = NULL;
#endif
*rootPP = addme;
*lastPP = addme;
return;
} /* if the list is empty */
if (target->sy_next != NULL)
{
#ifdef SYMBOLS_NEED_BACKPOINTERS
target->sy_next->sy_previous = addme;
#endif /* SYMBOLS_NEED_BACKPOINTERS */
}
else
{
know (*lastPP == target);
*lastPP = addme;
} /* if we have a next */
addme->sy_next = target->sy_next;
target->sy_next = addme;
#ifdef SYMBOLS_NEED_BACKPOINTERS
addme->sy_previous = target;
#endif /* SYMBOLS_NEED_BACKPOINTERS */
debug_verify_symchain (symbol_rootP, symbol_lastP);
}
/* Set the chain pointers of SYMBOL to null. */
void
symbol_clear_list_pointers (symbolP)
symbolS *symbolP;
{
symbolP->sy_next = NULL;
#ifdef SYMBOLS_NEED_BACKPOINTERS
symbolP->sy_previous = NULL;
#endif
}
#ifdef SYMBOLS_NEED_BACKPOINTERS
/* Remove SYMBOLP from the list. */
void
symbol_remove (symbolP, rootPP, lastPP)
symbolS *symbolP;
symbolS **rootPP;
symbolS **lastPP;
{
if (symbolP == *rootPP)
{
*rootPP = symbolP->sy_next;
} /* if it was the root */
if (symbolP == *lastPP)
{
*lastPP = symbolP->sy_previous;
} /* if it was the tail */
if (symbolP->sy_next != NULL)
{
symbolP->sy_next->sy_previous = symbolP->sy_previous;
} /* if not last */
if (symbolP->sy_previous != NULL)
{
symbolP->sy_previous->sy_next = symbolP->sy_next;
} /* if not first */
debug_verify_symchain (*rootPP, *lastPP);
}
/* Link symbol ADDME before symbol TARGET in the chain. */
void
symbol_insert (addme, target, rootPP, lastPP)
symbolS *addme;
symbolS *target;
symbolS **rootPP;
symbolS **lastPP;
{
if (target->sy_previous != NULL)
{
target->sy_previous->sy_next = addme;
}
else
{
know (*rootPP == target);
*rootPP = addme;
} /* if not first */
addme->sy_previous = target->sy_previous;
target->sy_previous = addme;
addme->sy_next = target;
debug_verify_symchain (*rootPP, *lastPP);
}
#endif /* SYMBOLS_NEED_BACKPOINTERS */
void
verify_symbol_chain (rootP, lastP)
symbolS *rootP;
symbolS *lastP;
{
symbolS *symbolP = rootP;
if (symbolP == NULL)
return;
for (; symbol_next (symbolP) != NULL; symbolP = symbol_next (symbolP))
{
#ifdef SYMBOLS_NEED_BACKPOINTERS
assert (symbolP->sy_next->sy_previous == symbolP);
#else
/* Walk the list anyways, to make sure pointers are still good. */
;
#endif /* SYMBOLS_NEED_BACKPOINTERS */
}
assert (lastP == symbolP);
}
void
verify_symbol_chain_2 (sym)
symbolS *sym;
{
symbolS *p = sym, *n = sym;
#ifdef SYMBOLS_NEED_BACKPOINTERS
while (symbol_previous (p))
p = symbol_previous (p);
#endif
while (symbol_next (n))
n = symbol_next (n);
verify_symbol_chain (p, n);
}
/* Resolve the value of a symbol. This is called during the final
pass over the symbol table to resolve any symbols with complex
values. */
valueT
resolve_symbol_value (symp, finalize)
symbolS *symp;
int finalize;
{
int resolved;
valueT final_val;
segT final_seg;
if (symp->sy_resolved)
{
if (symp->sy_value.X_op == O_constant)
return (valueT) symp->sy_value.X_add_number;
else
return 0;
}
resolved = 0;
final_seg = S_GET_SEGMENT (symp);
if (symp->sy_resolving)
{
if (finalize)
as_bad (_("Symbol definition loop encountered at %s"), S_GET_NAME (symp));
final_val = 0;
resolved = 1;
}
else
{
symbolS *add_symbol, *op_symbol;
offsetT left, right;
segT seg_left, seg_right;
operatorT op;
symp->sy_resolving = 1;
/* Help out with CSE. */
add_symbol = symp->sy_value.X_add_symbol;
op_symbol = symp->sy_value.X_op_symbol;
final_val = symp->sy_value.X_add_number;
op = symp->sy_value.X_op;
switch (op)
{
default:
BAD_CASE (op);
break;
case O_absent:
final_val = 0;
/* Fall through. */
case O_constant:
final_val += symp->sy_frag->fr_address;
if (final_seg == expr_section)
final_seg = absolute_section;
resolved = 1;
break;
case O_symbol:
case O_symbol_rva:
left = resolve_symbol_value (add_symbol, finalize);
do_symbol:
if (symp->sy_mri_common)
{
/* This is a symbol inside an MRI common section. The
relocation routines are going to handle it specially.
Don't change the value. */
resolved = add_symbol->sy_resolved;
break;
}
if (finalize && final_val == 0)
copy_symbol_attributes (symp, add_symbol);
/* If we have equated this symbol to an undefined symbol, we
keep X_op set to O_symbol, and we don't change
X_add_number. This permits the routine which writes out
relocation to detect this case, and convert the
relocation to be against the symbol to which this symbol
is equated. */
if (! S_IS_DEFINED (add_symbol) || S_IS_COMMON (add_symbol))
{
if (finalize)
{
S_SET_SEGMENT (symp, S_GET_SEGMENT (add_symbol));
symp->sy_value.X_op = O_symbol;
symp->sy_value.X_add_symbol = add_symbol;
symp->sy_value.X_add_number = final_val;
}
final_val = 0;
resolved = add_symbol->sy_resolved;
goto exit_dont_set_value;
}
else
{
final_val += symp->sy_frag->fr_address + left;
if (final_seg == expr_section || final_seg == undefined_section)
final_seg = S_GET_SEGMENT (add_symbol);
}
resolved = add_symbol->sy_resolved;
break;
case O_uminus:
case O_bit_not:
case O_logical_not:
left = resolve_symbol_value (add_symbol, finalize);
if (op == O_uminus)
left = -left;
else if (op == O_logical_not)
left = !left;
else
left = ~left;
final_val += left + symp->sy_frag->fr_address;
if (final_seg == expr_section || final_seg == undefined_section)
final_seg = absolute_section;
resolved = add_symbol->sy_resolved;
break;
case O_multiply:
case O_divide:
case O_modulus:
case O_left_shift:
case O_right_shift:
case O_bit_inclusive_or:
case O_bit_or_not:
case O_bit_exclusive_or:
case O_bit_and:
case O_add:
case O_subtract:
case O_eq:
case O_ne:
case O_lt:
case O_le:
case O_ge:
case O_gt:
case O_logical_and:
case O_logical_or:
left = resolve_symbol_value (add_symbol, finalize);
right = resolve_symbol_value (op_symbol, finalize);
seg_left = S_GET_SEGMENT (add_symbol);
seg_right = S_GET_SEGMENT (op_symbol);
/* Simplify addition or subtraction of a constant by folding the
constant into X_add_number. */
if (op == O_add || op == O_subtract)
{
if (seg_right == absolute_section)
{
if (op == O_add)
final_val += right;
else
final_val -= right;
op = O_symbol;
op_symbol = NULL;
goto do_symbol;
}
else if (seg_left == absolute_section && op == O_add)
{
op = O_symbol;
final_val += left;
add_symbol = op_symbol;
left = right;
op_symbol = NULL;
goto do_symbol;
}
}
/* Subtraction is permitted if both operands are in the same
section. Otherwise, both operands must be absolute. We
already handled the case of addition or subtraction of a
constant above. This will probably need to be changed
for an object file format which supports arbitrary
expressions, such as IEEE-695. */
/* Don't emit messages unless we're finalizing the symbol value,
otherwise we may get the same message multiple times. */
if ((seg_left != absolute_section || seg_right != absolute_section)
&& (op != O_subtract || seg_left != seg_right)
&& finalize)
{
char *file;
unsigned int line;
if (expr_symbol_where (symp, &file, &line))
{
if (seg_left == undefined_section)
as_bad_where (file, line,
_("undefined symbol %s in operation"),
S_GET_NAME (symp->sy_value.X_add_symbol));
if (seg_right == undefined_section)
as_bad_where (file, line,
_("undefined symbol %s in operation"),
S_GET_NAME (symp->sy_value.X_op_symbol));
if (seg_left != undefined_section
&& seg_right != undefined_section)
as_bad_where (file, line, _("invalid section for operation"));
}
else
{
if (seg_left == undefined_section)
as_bad (_("undefined symbol %s in operation setting %s"),
S_GET_NAME (symp->sy_value.X_add_symbol),
S_GET_NAME (symp));
if (seg_right == undefined_section)
as_bad (_("undefined symbol %s in operation setting %s"),
S_GET_NAME (symp->sy_value.X_op_symbol),
S_GET_NAME (symp));
if (seg_left != undefined_section
&& seg_right != undefined_section)
as_bad (_("invalid section for operation setting %s"),
S_GET_NAME (symp));
}
}
/* Check for division by zero. */
if ((op == O_divide || op == O_modulus) && right == 0)
{
/* If seg_right is not absolute_section, then we've
already issued a warning about using a bad symbol. */
if (seg_right == absolute_section && finalize)
{
char *file;
unsigned int line;
if (expr_symbol_where (symp, &file, &line))
as_bad_where (file, line, _("division by zero"));
else
as_bad (_("division by zero when setting %s"),
S_GET_NAME (symp));
}
right = 1;
}
switch (symp->sy_value.X_op)
{
case O_multiply: left *= right; break;
case O_divide: left /= right; break;
case O_modulus: left %= right; break;
case O_left_shift: left <<= right; break;
case O_right_shift: left >>= right; break;
case O_bit_inclusive_or: left |= right; break;
case O_bit_or_not: left |= ~right; break;
case O_bit_exclusive_or: left ^= right; break;
case O_bit_and: left &= right; break;
case O_add: left += right; break;
case O_subtract: left -= right; break;
case O_eq: left = left == right ? ~ (offsetT) 0 : 0; break;
case O_ne: left = left != right ? ~ (offsetT) 0 : 0; break;
case O_lt: left = left < right ? ~ (offsetT) 0 : 0; break;
case O_le: left = left <= right ? ~ (offsetT) 0 : 0; break;
case O_ge: left = left >= right ? ~ (offsetT) 0 : 0; break;
case O_gt: left = left > right ? ~ (offsetT) 0 : 0; break;
case O_logical_and: left = left && right; break;
case O_logical_or: left = left || right; break;
default: abort ();
}
final_val += symp->sy_frag->fr_address + left;
if (final_seg == expr_section || final_seg == undefined_section)
final_seg = absolute_section;
resolved = (add_symbol->sy_resolved && op_symbol->sy_resolved);
break;
case O_register:
case O_big:
case O_illegal:
/* Give an error (below) if not in expr_section. We don't
want to worry about expr_section symbols, because they
are fictional (they are created as part of expression
resolution), and any problems may not actually mean
anything. */
break;
}
symp->sy_resolving = 0;
}
if (finalize)
{
S_SET_VALUE (symp, final_val);
#if defined (OBJ_AOUT) && ! defined (BFD_ASSEMBLER)
/* The old a.out backend does not handle S_SET_SEGMENT correctly
for a stab symbol, so we use this bad hack. */
if (final_seg != S_GET_SEGMENT (symp))
#endif
S_SET_SEGMENT (symp, final_seg);
}
exit_dont_set_value:
/* Don't worry if we can't resolve an expr_section symbol. */
if (finalize)
{
if (resolved)
symp->sy_resolved = 1;
else if (S_GET_SEGMENT (symp) != expr_section)
{
as_bad (_("can't resolve value for symbol \"%s\""), S_GET_NAME (symp));
symp->sy_resolved = 1;
}
}
return final_val;
}
/* Dollar labels look like a number followed by a dollar sign. Eg, "42$".
They are *really* local. That is, they go out of scope whenever we see a
label that isn't local. Also, like fb labels, there can be multiple
instances of a dollar label. Therefor, we name encode each instance with
the instance number, keep a list of defined symbols separate from the real
symbol table, and we treat these buggers as a sparse array. */
static long *dollar_labels;
static long *dollar_label_instances;
static char *dollar_label_defines;
static unsigned long dollar_label_count;
static unsigned long dollar_label_max;
int
dollar_label_defined (label)
long label;
{
long *i;
know ((dollar_labels != NULL) || (dollar_label_count == 0));
for (i = dollar_labels; i < dollar_labels + dollar_label_count; ++i)
if (*i == label)
return dollar_label_defines[i - dollar_labels];
/* if we get here, label isn't defined */
return 0;
} /* dollar_label_defined() */
static long
dollar_label_instance (label)
long label;
{
long *i;
know ((dollar_labels != NULL) || (dollar_label_count == 0));
for (i = dollar_labels; i < dollar_labels + dollar_label_count; ++i)
if (*i == label)
return (dollar_label_instances[i - dollar_labels]);
/* If we get here, we haven't seen the label before, therefore its instance
count is zero. */
return 0;
}
void
dollar_label_clear ()
{
memset (dollar_label_defines, '\0', (unsigned int) dollar_label_count);
}
#define DOLLAR_LABEL_BUMP_BY 10
void
define_dollar_label (label)
long label;
{
long *i;
for (i = dollar_labels; i < dollar_labels + dollar_label_count; ++i)
if (*i == label)
{
++dollar_label_instances[i - dollar_labels];
dollar_label_defines[i - dollar_labels] = 1;
return;
}
/* if we get to here, we don't have label listed yet. */
if (dollar_labels == NULL)
{
dollar_labels = (long *) xmalloc (DOLLAR_LABEL_BUMP_BY * sizeof (long));
dollar_label_instances = (long *) xmalloc (DOLLAR_LABEL_BUMP_BY * sizeof (long));
dollar_label_defines = xmalloc (DOLLAR_LABEL_BUMP_BY);
dollar_label_max = DOLLAR_LABEL_BUMP_BY;
dollar_label_count = 0;
}
else if (dollar_label_count == dollar_label_max)
{
dollar_label_max += DOLLAR_LABEL_BUMP_BY;
dollar_labels = (long *) xrealloc ((char *) dollar_labels,
dollar_label_max * sizeof (long));
dollar_label_instances = (long *) xrealloc ((char *) dollar_label_instances,
dollar_label_max * sizeof (long));
dollar_label_defines = xrealloc (dollar_label_defines, dollar_label_max);
} /* if we needed to grow */
dollar_labels[dollar_label_count] = label;
dollar_label_instances[dollar_label_count] = 1;
dollar_label_defines[dollar_label_count] = 1;
++dollar_label_count;
}
/*
* dollar_label_name()
*
* Caller must copy returned name: we re-use the area for the next name.
*
* The mth occurence of label n: is turned into the symbol "Ln^Am"
* where n is the label number and m is the instance number. "L" makes
* it a label discarded unless debugging and "^A"('\1') ensures no
* ordinary symbol SHOULD get the same name as a local label
* symbol. The first "4:" is "L4^A1" - the m numbers begin at 1.
*
* fb labels get the same treatment, except that ^B is used in place of ^A.
*/
char * /* Return local label name. */
dollar_label_name (n, augend)
register long n; /* we just saw "n$:" : n a number */
register int augend; /* 0 for current instance, 1 for new instance */
{
long i;
/* Returned to caller, then copied. used for created names ("4f") */
static char symbol_name_build[24];
register char *p;
register char *q;
char symbol_name_temporary[20]; /* build up a number, BACKWARDS */
know (n >= 0);
know (augend == 0 || augend == 1);
p = symbol_name_build;
*p++ = 'L';
/* Next code just does sprintf( {}, "%d", n); */
/* label number */
q = symbol_name_temporary;
for (*q++ = 0, i = n; i; ++q)
{
*q = i % 10 + '0';
i /= 10;
}
while ((*p = *--q) != '\0')
++p;
*p++ = 1; /* ^A */
/* instance number */
q = symbol_name_temporary;
for (*q++ = 0, i = dollar_label_instance (n) + augend; i; ++q)
{
*q = i % 10 + '0';
i /= 10;
}
while ((*p++ = *--q) != '\0');;
/* The label, as a '\0' ended string, starts at symbol_name_build. */
return symbol_name_build;
}
/*
* Sombody else's idea of local labels. They are made by "n:" where n
* is any decimal digit. Refer to them with
* "nb" for previous (backward) n:
* or "nf" for next (forward) n:.
*
* We do a little better and let n be any number, not just a single digit, but
* since the other guy's assembler only does ten, we treat the first ten
* specially.
*
* Like someone else's assembler, we have one set of local label counters for
* entire assembly, not one set per (sub)segment like in most assemblers. This
* implies that one can refer to a label in another segment, and indeed some
* crufty compilers have done just that.
*
* Since there could be a LOT of these things, treat them as a sparse array.
*/
#define FB_LABEL_SPECIAL (10)
static long fb_low_counter[FB_LABEL_SPECIAL];
static long *fb_labels;
static long *fb_label_instances;
static long fb_label_count;
static long fb_label_max;
/* this must be more than FB_LABEL_SPECIAL */
#define FB_LABEL_BUMP_BY (FB_LABEL_SPECIAL + 6)
static void
fb_label_init ()
{
memset ((void *) fb_low_counter, '\0', sizeof (fb_low_counter));
} /* fb_label_init() */
/* add one to the instance number of this fb label */
void
fb_label_instance_inc (label)
long label;
{
long *i;
if (label < FB_LABEL_SPECIAL)
{
++fb_low_counter[label];
return;
}
if (fb_labels != NULL)
{
for (i = fb_labels + FB_LABEL_SPECIAL;
i < fb_labels + fb_label_count; ++i)
{
if (*i == label)
{
++fb_label_instances[i - fb_labels];
return;
} /* if we find it */
} /* for each existing label */
}
/* if we get to here, we don't have label listed yet. */
if (fb_labels == NULL)
{
fb_labels = (long *) xmalloc (FB_LABEL_BUMP_BY * sizeof (long));
fb_label_instances = (long *) xmalloc (FB_LABEL_BUMP_BY * sizeof (long));
fb_label_max = FB_LABEL_BUMP_BY;
fb_label_count = FB_LABEL_SPECIAL;
}
else if (fb_label_count == fb_label_max)
{
fb_label_max += FB_LABEL_BUMP_BY;
fb_labels = (long *) xrealloc ((char *) fb_labels,
fb_label_max * sizeof (long));
fb_label_instances = (long *) xrealloc ((char *) fb_label_instances,
fb_label_max * sizeof (long));
} /* if we needed to grow */
fb_labels[fb_label_count] = label;
fb_label_instances[fb_label_count] = 1;
++fb_label_count;
}
static long
fb_label_instance (label)
long label;
{
long *i;
if (label < FB_LABEL_SPECIAL)
{
return (fb_low_counter[label]);
}
if (fb_labels != NULL)
{
for (i = fb_labels + FB_LABEL_SPECIAL;
i < fb_labels + fb_label_count; ++i)
{
if (*i == label)
{
return (fb_label_instances[i - fb_labels]);
} /* if we find it */
} /* for each existing label */
}
/* We didn't find the label, so this must be a reference to the
first instance. */
return 0;
}
/*
* fb_label_name()
*
* Caller must copy returned name: we re-use the area for the next name.
*
* The mth occurence of label n: is turned into the symbol "Ln^Bm"
* where n is the label number and m is the instance number. "L" makes
* it a label discarded unless debugging and "^B"('\2') ensures no
* ordinary symbol SHOULD get the same name as a local label
* symbol. The first "4:" is "L4^B1" - the m numbers begin at 1.
*
* dollar labels get the same treatment, except that ^A is used in place of ^B. */
char * /* Return local label name. */
fb_label_name (n, augend)
long n; /* we just saw "n:", "nf" or "nb" : n a number */
long augend; /* 0 for nb, 1 for n:, nf */
{
long i;
/* Returned to caller, then copied. used for created names ("4f") */
static char symbol_name_build[24];
register char *p;
register char *q;
char symbol_name_temporary[20]; /* build up a number, BACKWARDS */
know (n >= 0);
know (augend == 0 || augend == 1);
p = symbol_name_build;
*p++ = 'L';
/* Next code just does sprintf( {}, "%d", n); */
/* label number */
q = symbol_name_temporary;
for (*q++ = 0, i = n; i; ++q)
{
*q = i % 10 + '0';
i /= 10;
}
while ((*p = *--q) != '\0')
++p;
*p++ = 2; /* ^B */
/* instance number */
q = symbol_name_temporary;
for (*q++ = 0, i = fb_label_instance (n) + augend; i; ++q)
{
*q = i % 10 + '0';
i /= 10;
}
while ((*p++ = *--q) != '\0');;
/* The label, as a '\0' ended string, starts at symbol_name_build. */
return (symbol_name_build);
} /* fb_label_name() */
/*
* decode name that may have been generated by foo_label_name() above. If
* the name wasn't generated by foo_label_name(), then return it unaltered.
* This is used for error messages.
*/
char *
decode_local_label_name (s)
char *s;
{
char *p;
char *symbol_decode;
int label_number;
int instance_number;
char *type;
const char *message_format = _("\"%d\" (instance number %d of a %s label)");
if (s[0] != 'L')
return s;
for (label_number = 0, p = s + 1; isdigit ((unsigned char) *p); ++p)
label_number = (10 * label_number) + *p - '0';
if (*p == 1)
type = "dollar";
else if (*p == 2)
type = "fb";
else
return s;
for (instance_number = 0, p++; isdigit ((unsigned char) *p); ++p)
instance_number = (10 * instance_number) + *p - '0';
symbol_decode = obstack_alloc (&notes, strlen (message_format) + 30);
sprintf (symbol_decode, message_format, label_number, instance_number, type);
return symbol_decode;
}
/* Get the value of a symbol. */
valueT
S_GET_VALUE (s)
symbolS *s;
{
if (!s->sy_resolved && s->sy_value.X_op != O_constant)
resolve_symbol_value (s, 1);
if (s->sy_value.X_op != O_constant)
{
static symbolS *recur;
/* FIXME: In non BFD assemblers, S_IS_DEFINED and S_IS_COMMON
may call S_GET_VALUE. We use a static symbol to avoid the
immediate recursion. */
if (recur == s)
return (valueT) s->sy_value.X_add_number;
recur = s;
if (! s->sy_resolved
|| s->sy_value.X_op != O_symbol
|| (S_IS_DEFINED (s) && ! S_IS_COMMON (s)))
as_bad (_("Attempt to get value of unresolved symbol %s"),
S_GET_NAME (s));
recur = NULL;
}
return (valueT) s->sy_value.X_add_number;
}
/* Set the value of a symbol. */
void
S_SET_VALUE (s, val)
symbolS *s;
valueT val;
{
s->sy_value.X_op = O_constant;
s->sy_value.X_add_number = (offsetT) val;
s->sy_value.X_unsigned = 0;
}
void
copy_symbol_attributes (dest, src)
symbolS *dest, *src;
{
#ifdef BFD_ASSEMBLER
/* In an expression, transfer the settings of these flags.
The user can override later, of course. */
#define COPIED_SYMFLAGS (BSF_FUNCTION | BSF_OBJECT)
dest->bsym->flags |= src->bsym->flags & COPIED_SYMFLAGS;
#endif
#ifdef OBJ_COPY_SYMBOL_ATTRIBUTES
OBJ_COPY_SYMBOL_ATTRIBUTES (dest, src);
#endif
}
#ifdef BFD_ASSEMBLER
int
S_IS_FUNCTION (s)
symbolS *s;
{
flagword flags = s->bsym->flags;
return (flags & BSF_FUNCTION) != 0;
}
int
S_IS_EXTERNAL (s)
symbolS *s;
{
flagword flags = s->bsym->flags;
/* sanity check */
if ((flags & BSF_LOCAL) && (flags & BSF_GLOBAL))
abort ();
return (flags & BSF_GLOBAL) != 0;
}
int
S_IS_WEAK (s)
symbolS *s;
{
return (s->bsym->flags & BSF_WEAK) != 0;
}
int
S_IS_COMMON (s)
symbolS *s;
{
return bfd_is_com_section (s->bsym->section);
}
int
S_IS_DEFINED (s)
symbolS *s;
{
return s->bsym->section != undefined_section;
}
int
S_IS_DEBUG (s)
symbolS *s;
{
if (s->bsym->flags & BSF_DEBUGGING)
return 1;
return 0;
}
int
S_IS_LOCAL (s)
symbolS *s;
{
flagword flags = s->bsym->flags;
const char *name;
/* sanity check */
if ((flags & BSF_LOCAL) && (flags & BSF_GLOBAL))
abort ();
if (bfd_get_section (s->bsym) == reg_section)
return 1;
if (flag_strip_local_absolute
&& (flags & BSF_GLOBAL) == 0
&& bfd_get_section (s->bsym) == absolute_section)
return 1;
name = S_GET_NAME (s);
return (name != NULL
&& ! S_IS_DEBUG (s)
&& (strchr (name, '\001')
|| strchr (name, '\002')
|| (! flag_keep_locals
&& (bfd_is_local_label (stdoutput, s->bsym)
|| (flag_mri
&& name[0] == '?'
&& name[1] == '?')))));
}
int
S_IS_EXTERN (s)
symbolS *s;
{
return S_IS_EXTERNAL (s);
}
int
S_IS_STABD (s)
symbolS *s;
{
return S_GET_NAME (s) == 0;
}
CONST char *
S_GET_NAME (s)
symbolS *s;
{
return s->bsym->name;
}
segT
S_GET_SEGMENT (s)
symbolS *s;
{
return s->bsym->section;
}
void
S_SET_SEGMENT (s, seg)
symbolS *s;
segT seg;
{
/* Don't reassign section symbols. The direct reason is to prevent seg
faults assigning back to const global symbols such as *ABS*, but it
shouldn't happen anyway. */
if (s->bsym->flags & BSF_SECTION_SYM)
{
if (s->bsym->section != seg)
abort();
}
else
s->bsym->section = seg;
}
void
S_SET_EXTERNAL (s)
symbolS *s;
{
if ((s->bsym->flags & BSF_WEAK) != 0)
{
/* Let .weak override .global. */
return;
}
s->bsym->flags |= BSF_GLOBAL;
s->bsym->flags &= ~(BSF_LOCAL|BSF_WEAK);
}
void
S_CLEAR_EXTERNAL (s)
symbolS *s;
{
if ((s->bsym->flags & BSF_WEAK) != 0)
{
/* Let .weak override. */
return;
}
s->bsym->flags |= BSF_LOCAL;
s->bsym->flags &= ~(BSF_GLOBAL|BSF_WEAK);
}
void
S_SET_WEAK (s)
symbolS *s;
{
s->bsym->flags |= BSF_WEAK;
s->bsym->flags &= ~(BSF_GLOBAL|BSF_LOCAL);
}
void
S_SET_NAME (s, name)
symbolS *s;
char *name;
{
s->bsym->name = name;
}
#endif /* BFD_ASSEMBLER */
void
symbol_begin ()
{
symbol_lastP = NULL;
symbol_rootP = NULL; /* In case we have 0 symbols (!!) */
sy_hash = hash_new ();
memset ((char *) (&abs_symbol), '\0', sizeof (abs_symbol));
#ifdef BFD_ASSEMBLER
#if defined (EMIT_SECTION_SYMBOLS) || !defined (RELOC_REQUIRES_SYMBOL)
abs_symbol.bsym = bfd_abs_section.symbol;
#endif
#else
/* Can't initialise a union. Sigh. */
S_SET_SEGMENT (&abs_symbol, absolute_section);
#endif
abs_symbol.sy_value.X_op = O_constant;
abs_symbol.sy_frag = &zero_address_frag;
if (LOCAL_LABELS_FB)
fb_label_init ();
}
int indent_level;
/* Maximum indent level.
Available for modification inside a gdb session. */
int max_indent_level = 8;
#if 0
static void
indent ()
{
printf ("%*s", indent_level * 4, "");
}
#endif
void
print_symbol_value_1 (file, sym)
FILE *file;
symbolS *sym;
{
const char *name = S_GET_NAME (sym);
if (!name || !name[0])
name = "(unnamed)";
fprintf (file, "sym %lx %s", (unsigned long) sym, name);
if (sym->sy_frag != &zero_address_frag)
fprintf (file, " frag %lx", (long) sym->sy_frag);
if (sym->written)
fprintf (file, " written");
if (sym->sy_resolved)
fprintf (file, " resolved");
else if (sym->sy_resolving)
fprintf (file, " resolving");
if (sym->sy_used_in_reloc)
fprintf (file, " used-in-reloc");
if (sym->sy_used)
fprintf (file, " used");
if (S_IS_LOCAL (sym))
fprintf (file, " local");
if (S_IS_EXTERN (sym))
fprintf (file, " extern");
if (S_IS_DEBUG (sym))
fprintf (file, " debug");
if (S_IS_DEFINED (sym))
fprintf (file, " defined");
fprintf (file, " %s", segment_name (S_GET_SEGMENT (sym)));
if (sym->sy_resolved)
{
segT s = S_GET_SEGMENT (sym);
if (s != undefined_section
&& s != expr_section)
fprintf (file, " %lx", (long) S_GET_VALUE (sym));
}
else if (indent_level < max_indent_level
&& S_GET_SEGMENT (sym) != undefined_section)
{
indent_level++;
fprintf (file, "\n%*s<", indent_level * 4, "");
print_expr_1 (file, &sym->sy_value);
fprintf (file, ">");
indent_level--;
}
fflush (file);
}
void
print_symbol_value (sym)
symbolS *sym;
{
indent_level = 0;
print_symbol_value_1 (stderr, sym);
fprintf (stderr, "\n");
}
static void
print_binary (file, name, exp)
FILE *file;
const char * name;
expressionS *exp;
{
indent_level++;
fprintf (file, "%s\n%*s<", name, indent_level * 4, "");
print_symbol_value_1 (file, exp->X_add_symbol);
fprintf (file, ">\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_op_symbol);
fprintf (file, ">");
indent_level--;
}
void
print_expr_1 (file, exp)
FILE *file;
expressionS *exp;
{
fprintf (file, "expr %lx ", (long) exp);
switch (exp->X_op)
{
case O_illegal:
fprintf (file, "illegal");
break;
case O_absent:
fprintf (file, "absent");
break;
case O_constant:
fprintf (file, "constant %lx", (long) exp->X_add_number);
break;
case O_symbol:
indent_level++;
fprintf (file, "symbol\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_add_symbol);
fprintf (file, ">");
maybe_print_addnum:
if (exp->X_add_number)
fprintf (file, "\n%*s%lx", indent_level * 4, "",
(long) exp->X_add_number);
indent_level--;
break;
case O_register:
fprintf (file, "register #%d", (int) exp->X_add_number);
break;
case O_big:
fprintf (file, "big");
break;
case O_uminus:
fprintf (file, "uminus -<");
indent_level++;
print_symbol_value_1 (file, exp->X_add_symbol);
fprintf (file, ">");
goto maybe_print_addnum;
case O_bit_not:
fprintf (file, "bit_not");
break;
case O_multiply:
print_binary (file, "multiply", exp);
break;
case O_divide:
print_binary (file, "divide", exp);
break;
case O_modulus:
print_binary (file, "modulus", exp);
break;
case O_left_shift:
print_binary (file, "lshift", exp);
break;
case O_right_shift:
print_binary (file, "rshift", exp);
break;
case O_bit_inclusive_or:
print_binary (file, "bit_ior", exp);
break;
case O_bit_exclusive_or:
print_binary (file, "bit_xor", exp);
break;
case O_bit_and:
print_binary (file, "bit_and", exp);
break;
case O_eq:
print_binary (file, "eq", exp);
break;
case O_ne:
print_binary (file, "ne", exp);
break;
case O_lt:
print_binary (file, "lt", exp);
break;
case O_le:
print_binary (file, "le", exp);
break;
case O_ge:
print_binary (file, "ge", exp);
break;
case O_gt:
print_binary (file, "gt", exp);
break;
case O_logical_and:
print_binary (file, "logical_and", exp);
break;
case O_logical_or:
print_binary (file, "logical_or", exp);
break;
case O_add:
indent_level++;
fprintf (file, "add\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_add_symbol);
fprintf (file, ">\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_op_symbol);
fprintf (file, ">");
goto maybe_print_addnum;
case O_subtract:
indent_level++;
fprintf (file, "subtract\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_add_symbol);
fprintf (file, ">\n%*s<", indent_level * 4, "");
print_symbol_value_1 (file, exp->X_op_symbol);
fprintf (file, ">");
goto maybe_print_addnum;
default:
fprintf (file, "{unknown opcode %d}", (int) exp->X_op);
break;
}
fflush (stdout);
}
void
print_expr (exp)
expressionS *exp;
{
print_expr_1 (stderr, exp);
fprintf (stderr, "\n");
}
void
symbol_print_statistics (file)
FILE *file;
{
hash_print_statistics (file, "symbol table", sy_hash);
}
/* end of symbols.c */
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