binutils-gdb/gas/symbols.c

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/* symbols.c -symbol table-
Copyright (C) 1987, 1990, 1991, 1992, 1993 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
/* #define DEBUG_SYMS / * to debug symbol list maintenance */
#include <ctype.h>
#include "as.h"
#include "obstack.h" /* For "symbols.h" */
#include "subsegs.h"
#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;
struct obstack notes;
static void fb_label_init PARAMS ((void));
/*
* 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.
*
*
* Please always call this to create a new symbol.
*
* Changes since 1985: Symbol names may not contain '\0'. Sigh.
* 2nd argument is now a SEG rather than a TYPE. The mapping between
* segments and types is mostly encapsulated herein (actually, we inherit it
* from macros in struc-symbol.h).
*/
symbolS *
symbol_new (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
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);
assert (symbolP->bsym != 0);
symbolP->bsym->udata = (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
/*
* Link to end of symbol chain.
*/
symbol_append (symbolP, symbol_lastP, &symbol_rootP, &symbol_lastP);
obj_symbol_new_hook (symbolP);
#ifdef DEBUG_SYMS
verify_symbol_chain(symbol_rootP, symbol_lastP);
#endif /* DEBUG_SYMS */
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).
*
*/
void
colon (sym_name) /* just seen "x:" - rattle symbols & frags */
register 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 */
#ifdef LOCAL_LABELS_DOLLAR
/* Sun local labels go out of scope whenever a non-local symbol is
defined. */
if (*sym_name != 'L')
dollar_label_clear ();
#endif /* LOCAL_LABELS_DOLLAR */
#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,
0L,
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;
#endif
/*
* Now check for undefined symbols
*/
if (!S_IS_DEFINED (symbolP))
{
if (S_GET_VALUE (symbolP) == 0)
{
symbolP->sy_frag = frag_now;
#ifdef OBJ_VMS
S_GET_OTHER(symbolP) = const_flag;
#endif
S_SET_VALUE (symbolP, (valueT) ((char*)obstack_next_free (&frags) - frag_now->fr_literal));
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_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_GET_OTHER(symbolP) = const_flag;
#endif /* OBJ_VMS */
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) == (char*)obstack_next_free (&frags) - frag_now->fr_literal
&& 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) ((char*)obstack_next_free (&frags) - frag_now->fr_literal),
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 */
#ifdef tc_frob_label
tc_frob_label (symbolP);
#endif
}
/*
* 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)
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++;
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);
*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 */
}
#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 */
#ifdef DEBUG_SYMS
verify_symbol_chain (*rootPP, *lastPP);
#endif /* DEBUG_SYMS */
}
/* Set the chain pointers of SYMBOL to null. */
void
symbol_clear_list_pointers (symbolP)
symbolS *symbolP;
{
symbolP->sy_next = NULL;
symbolP->sy_previous = NULL;
}
/* 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;
#ifdef DEBUG_SYMS
verify_symbol_chain (*rootPP, *lastPP);
#endif /* DEBUG_SYMS */
}
#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
know (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. */
void
resolve_symbol_value (symp)
symbolS *symp;
{
int resolved;
if (symp->sy_resolved)
return;
resolved = 0;
if (symp->sy_resolving)
{
as_bad ("Symbol definition loop encountered at %s",
S_GET_NAME (symp));
S_SET_VALUE (symp, (valueT) 0);
resolved = 1;
}
else
{
offsetT left, right, val;
segT seg_left, seg_right;
symp->sy_resolving = 1;
switch (symp->sy_value.X_op)
{
case O_absent:
S_SET_VALUE (symp, 0);
/* Fall through. */
case O_constant:
S_SET_VALUE (symp, S_GET_VALUE (symp) + symp->sy_frag->fr_address);
if (S_GET_SEGMENT (symp) == expr_section)
S_SET_SEGMENT (symp, absolute_section);
resolved = 1;
break;
case O_symbol:
resolve_symbol_value (symp->sy_value.X_add_symbol);
#ifdef obj_frob_forward_symbol
/* Some object formats need to forward the segment. */
obj_frob_forward_symbol (symp);
#endif
S_SET_VALUE (symp,
(symp->sy_value.X_add_number
+ symp->sy_frag->fr_address
+ S_GET_VALUE (symp->sy_value.X_add_symbol)));
if (S_GET_SEGMENT (symp) == expr_section
|| S_GET_SEGMENT (symp) == undefined_section)
S_SET_SEGMENT (symp,
S_GET_SEGMENT (symp->sy_value.X_add_symbol));
resolved = symp->sy_value.X_add_symbol->sy_resolved;
break;
case O_uminus:
case O_bit_not:
resolve_symbol_value (symp->sy_value.X_add_symbol);
if (symp->sy_value.X_op == O_uminus)
val = - S_GET_VALUE (symp->sy_value.X_add_symbol);
else
val = ~ S_GET_VALUE (symp->sy_value.X_add_symbol);
S_SET_VALUE (symp,
(val
+ symp->sy_value.X_add_number
+ symp->sy_frag->fr_address));
if (S_GET_SEGMENT (symp) == expr_section
|| S_GET_SEGMENT (symp) == undefined_section)
S_SET_SEGMENT (symp, absolute_section);
resolved = symp->sy_value.X_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:
resolve_symbol_value (symp->sy_value.X_add_symbol);
resolve_symbol_value (symp->sy_value.X_op_symbol);
seg_left = S_GET_SEGMENT (symp->sy_value.X_add_symbol);
seg_right = S_GET_SEGMENT (symp->sy_value.X_op_symbol);
if (seg_left != seg_right
&& seg_left != undefined_section
&& seg_right != undefined_section)
as_bad ("%s is operation on symbols in different sections",
S_GET_NAME (symp));
if ((S_GET_SEGMENT (symp->sy_value.X_add_symbol)
!= absolute_section)
&& symp->sy_value.X_op != O_subtract)
as_bad ("%s is illegal operation on non-absolute symbols",
S_GET_NAME (symp));
left = S_GET_VALUE (symp->sy_value.X_add_symbol);
right = S_GET_VALUE (symp->sy_value.X_op_symbol);
switch (symp->sy_value.X_op)
{
case O_multiply: val = left * right; break;
case O_divide: val = left / right; break;
case O_modulus: val = left % right; break;
case O_left_shift: val = left << right; break;
case O_right_shift: val = left >> right; break;
case O_bit_inclusive_or: val = left | right; break;
case O_bit_or_not: val = left |~ right; break;
case O_bit_exclusive_or: val = left ^ right; break;
case O_bit_and: val = left & right; break;
case O_add: val = left + right; break;
case O_subtract: val = left - right; break;
default: abort ();
}
S_SET_VALUE (symp,
(symp->sy_value.X_add_number
+ symp->sy_frag->fr_address
+ val));
if (S_GET_SEGMENT (symp) == expr_section
|| S_GET_SEGMENT (symp) == undefined_section)
S_SET_SEGMENT (symp, absolute_section);
resolved = (symp->sy_value.X_add_symbol->sy_resolved
&& symp->sy_value.X_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;
}
}
/* Don't worry if we can't resolve an expr_section symbol. */
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;
}
}
#ifdef LOCAL_LABELS_DOLLAR
/* 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 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 int
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;
}
#endif /* LOCAL_LABELS_DOLLAR */
#ifdef LOCAL_LABELS_FB
/*
* 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() */
#endif /* LOCAL_LABELS_FB */
/*
* 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 (*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 = s + 1; isdigit (*p); ++p)
{
instance_number = (10 * instance_number) + *p - '0';
}
symbol_decode = obstack_alloc (&notes, strlen (message_format) + 30);
(void) sprintf (symbol_decode, message_format, label_number,
instance_number, type);
return (symbol_decode);
} /* decode_local_label_name() */
/* Get the value of a symbol. */
valueT
S_GET_VALUE (s)
symbolS *s;
{
if (s->sy_value.X_op != O_constant)
as_bad ("Attempt to get value of unresolved symbol %s", S_GET_NAME (s));
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;
}
#ifdef BFD_ASSEMBLER
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_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;
/* sanity check */
if (flags & BSF_LOCAL && flags & BSF_GLOBAL)
abort ();
return (S_GET_NAME (s)
&& ! S_IS_DEBUG (s)
&& (strchr (S_GET_NAME (s), '\001')
|| strchr (S_GET_NAME (s), '\002')
|| (S_LOCAL_NAME (s)
&& !flagseen['L'])));
}
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;
{
s->bsym->section = seg;
}
void
S_SET_EXTERNAL (s)
symbolS *s;
{
s->bsym->flags |= BSF_GLOBAL;
s->bsym->flags &= ~(BSF_LOCAL|BSF_WEAK);
}
void
S_CLEAR_EXTERNAL (s)
symbolS *s;
{
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
abs_symbol.bsym = bfd_abs_section.symbol;
#else
/* Can't initialise a union. Sigh. */
S_SET_SEGMENT (&abs_symbol, absolute_section);
#endif
#ifdef LOCAL_LABELS_FB
fb_label_init ();
#endif /* LOCAL_LABELS_FB */
}
/* end of symbols.c */