/* symbols.c -symbol table-
- Copyright (C) 1987-2018 Free Software Foundation, Inc.
+ Copyright (C) 1987-2020 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
#include "safe-ctype.h"
#include "obstack.h" /* For "symbols.h" */
#include "subsegs.h"
-#include "struc-symbol.h"
#include "write.h"
+struct symbol_flags
+{
+ /* Whether the symbol is a local_symbol. */
+ unsigned int sy_local_symbol : 1;
+
+ /* Weather symbol has been written. */
+ unsigned int sy_written : 1;
+
+ /* Whether symbol value has been completely resolved (used during
+ final pass over symbol table). */
+ unsigned int sy_resolved : 1;
+
+ /* Whether the symbol value is currently being resolved (used to
+ detect loops in symbol dependencies). */
+ unsigned int sy_resolving : 1;
+
+ /* Whether the symbol value is used in a reloc. This is used to
+ ensure that symbols used in relocs are written out, even if they
+ are local and would otherwise not be. */
+ unsigned int sy_used_in_reloc : 1;
+
+ /* Whether the symbol is used as an operand or in an expression.
+ NOTE: Not all the backends keep this information accurate;
+ backends which use this bit are responsible for setting it when
+ a symbol is used in backend routines. */
+ unsigned int sy_used : 1;
+
+ /* Whether the symbol can be re-defined. */
+ unsigned int sy_volatile : 1;
+
+ /* Whether the symbol is a forward reference. */
+ unsigned int sy_forward_ref : 1;
+
+ /* This is set if the symbol is defined in an MRI common section.
+ We handle such sections as single common symbols, so symbols
+ defined within them must be treated specially by the relocation
+ routines. */
+ unsigned int sy_mri_common : 1;
+
+ /* This is set if the symbol is set with a .weakref directive. */
+ unsigned int sy_weakrefr : 1;
+
+ /* This is set when the symbol is referenced as part of a .weakref
+ directive, but only if the symbol was not in the symbol table
+ before. It is cleared as soon as any direct reference to the
+ symbol is present. */
+ unsigned int sy_weakrefd : 1;
+};
+
+/* The information we keep for a symbol. Note that the symbol table
+ holds pointers both to this and to local_symbol structures. See
+ below. */
+
+struct symbol
+{
+ /* Symbol flags. */
+ struct symbol_flags sy_flags;
+
+ /* BFD symbol */
+ asymbol *bsym;
+
+ /* The value of the symbol. */
+ expressionS sy_value;
+
+ /* Forwards and (optionally) backwards chain pointers. */
+ struct symbol *sy_next;
+ struct symbol *sy_previous;
+
+ /* Pointer to the frag this symbol is attached to, if any.
+ Otherwise, NULL. */
+ struct frag *sy_frag;
+
+#ifdef OBJ_SYMFIELD_TYPE
+ OBJ_SYMFIELD_TYPE sy_obj;
+#endif
+
+#ifdef TC_SYMFIELD_TYPE
+ TC_SYMFIELD_TYPE sy_tc;
+#endif
+
+#ifdef TARGET_SYMBOL_FIELDS
+ TARGET_SYMBOL_FIELDS
+#endif
+};
+
+/* A pointer in the symbol may point to either a complete symbol
+ (struct symbol above) or to a local symbol (struct local_symbol
+ defined here). The symbol code can detect the case by examining
+ the first field. It is always NULL for a local symbol.
+
+ We do this because we ordinarily only need a small amount of
+ information for a local symbol. The symbol table takes up a lot of
+ space, and storing less information for a local symbol can make a
+ big difference in assembler memory usage when assembling a large
+ file. */
+
+struct local_symbol
+{
+ /* Symbol flags. Only sy_local_symbol and sy_resolved are relevant. */
+ struct symbol_flags lsy_flags;
+
+ /* The symbol section. This also serves as a flag. If this is
+ reg_section, then this symbol has been converted into a regular
+ symbol, and lsy_sym points to it. */
+ segT lsy_section;
+
+ /* The symbol name. */
+ const char *lsy_name;
+
+ /* The symbol frag or the real symbol, depending upon the value in
+ lsy_section. */
+ union
+ {
+ fragS *lsy_frag;
+ symbolS *lsy_sym;
+ } u;
+
+ /* The value of the symbol. */
+ valueT lsy_value;
+
+#ifdef TC_LOCAL_SYMFIELD_TYPE
+ TC_LOCAL_SYMFIELD_TYPE lsy_tc;
+#endif
+};
+
+#define local_symbol_converted_p(l) ((l)->lsy_section == reg_section)
+#define local_symbol_mark_converted(l) ((l)->lsy_section = reg_section)
+#define local_symbol_resolved_p(l) ((l)->lsy_flags.sy_resolved)
+#define local_symbol_mark_resolved(l) ((l)->lsy_flags.sy_resolved = 1)
+#define local_symbol_get_frag(l) ((l)->u.lsy_frag)
+#define local_symbol_set_frag(l, f) ((l)->u.lsy_frag = (f))
+#define local_symbol_get_real_symbol(l) ((l)->u.lsy_sym)
+#define local_symbol_set_real_symbol(l, s) ((l)->u.lsy_sym = (s))
+
/* This is non-zero if symbols are case sensitive, which is the
default. */
int symbols_case_sensitive = 1;
return newsymP;
}
+/* If S is a local symbol that has been converted, return the
+ converted symbol. Otherwise return S. */
+
+static inline symbolS *
+get_real_sym (symbolS *s)
+{
+ if (s != NULL
+ && s->sy_flags.sy_local_symbol
+ && local_symbol_converted_p ((struct local_symbol *) s))
+ s = local_symbol_get_real_symbol ((struct local_symbol *) s);
+ return s;
+}
+
/* Referenced symbols, if they are forward references, need to be cloned
(without replacing the original) so that the value of the referenced
- symbols at the point of use . */
+ symbols at the point of use is saved by the clone. */
#undef symbol_clone_if_forward_ref
symbolS *
{
if (symbolP && !LOCAL_SYMBOL_CHECK (symbolP))
{
- symbolS *add_symbol = symbolP->sy_value.X_add_symbol;
- symbolS *op_symbol = symbolP->sy_value.X_op_symbol;
+ symbolS *orig_add_symbol = get_real_sym (symbolP->sy_value.X_add_symbol);
+ symbolS *orig_op_symbol = get_real_sym (symbolP->sy_value.X_op_symbol);
+ symbolS *add_symbol = orig_add_symbol;
+ symbolS *op_symbol = orig_op_symbol;
if (symbolP->sy_flags.sy_forward_ref)
is_forward = 1;
}
if (symbolP->sy_flags.sy_forward_ref
- || add_symbol != symbolP->sy_value.X_add_symbol
- || op_symbol != symbolP->sy_value.X_op_symbol)
+ || add_symbol != orig_add_symbol
+ || op_symbol != orig_op_symbol)
{
if (symbolP != &dot_symbol)
{
return symbol_temp_new (now_seg, frag_now_fix (), frag_now);
}
+symbolS *
+symbol_temp_new_now_octets (void)
+{
+ return symbol_temp_new (now_seg, frag_now_fix_octets (), frag_now);
+}
+
symbolS *
symbol_temp_make (void)
{
gas_assert (lastP == symbolP);
}
+int
+symbol_on_chain (symbolS *s, symbolS *rootPP, symbolS *lastPP)
+{
+ return (!LOCAL_SYMBOL_CHECK (s)
+ && ((s->sy_next != s
+ && s->sy_next != NULL
+ && s->sy_next->sy_previous == s)
+ || s == lastPP)
+ && ((s->sy_previous != s
+ && s->sy_previous != NULL
+ && s->sy_previous->sy_next == s)
+ || s == rootPP));
+}
+
#ifdef OBJ_COMPLEX_RELC
static int
case O_constant:
return 0;
- case O_symbol:
- case O_symbol_rva:
- case O_uminus:
- case O_bit_not:
- case O_logical_not:
- if ( (S_IS_COMMON (symp->sy_value.X_add_symbol)
- || S_IS_LOCAL (symp->sy_value.X_add_symbol))
- &&
- (S_IS_DEFINED (symp->sy_value.X_add_symbol)
- && S_GET_SEGMENT (symp->sy_value.X_add_symbol) != expr_section))
- return 0;
- break;
-
case O_multiply:
case O_divide:
case O_modulus:
case O_gt:
case O_logical_and:
case O_logical_or:
-
- if ( (S_IS_COMMON (symp->sy_value.X_add_symbol)
- || S_IS_LOCAL (symp->sy_value.X_add_symbol))
- &&
- (S_IS_COMMON (symp->sy_value.X_op_symbol)
+ if ((S_IS_COMMON (symp->sy_value.X_op_symbol)
|| S_IS_LOCAL (symp->sy_value.X_op_symbol))
-
- && S_IS_DEFINED (symp->sy_value.X_add_symbol)
&& S_IS_DEFINED (symp->sy_value.X_op_symbol)
- && S_GET_SEGMENT (symp->sy_value.X_add_symbol) != expr_section
&& S_GET_SEGMENT (symp->sy_value.X_op_symbol) != expr_section)
- return 0;
+ {
+ case O_symbol:
+ case O_symbol_rva:
+ case O_uminus:
+ case O_bit_not:
+ case O_logical_not:
+ if ((S_IS_COMMON (symp->sy_value.X_add_symbol)
+ || S_IS_LOCAL (symp->sy_value.X_add_symbol))
+ && S_IS_DEFINED (symp->sy_value.X_add_symbol)
+ && S_GET_SEGMENT (symp->sy_value.X_add_symbol) != expr_section)
+ return 0;
+ }
break;
default:
resolve_symbol_value (symbolS *symp)
{
int resolved;
- valueT final_val = 0;
+ valueT final_val;
segT final_seg;
if (LOCAL_SYMBOL_CHECK (symp))
if (local_symbol_resolved_p (locsym))
return final_val;
- final_val += local_symbol_get_frag (locsym)->fr_address / OCTETS_PER_BYTE;
+ /* Symbols whose section has SEC_ELF_OCTETS set,
+ resolve to octets instead of target bytes. */
+ if (locsym->lsy_section->flags & SEC_OCTETS)
+ final_val += local_symbol_get_frag (locsym)->fr_address;
+ else
+ final_val += (local_symbol_get_frag (locsym)->fr_address
+ / OCTETS_PER_BYTE);
if (finalize_syms)
{
if (symp->sy_flags.sy_resolved)
{
+ final_val = 0;
+ while (symp->sy_value.X_op == O_symbol
+ && symp->sy_value.X_add_symbol->sy_flags.sy_resolved)
+ {
+ final_val += symp->sy_value.X_add_number;
+ symp = symp->sy_value.X_add_symbol;
+ }
if (symp->sy_value.X_op == O_constant)
- return (valueT) symp->sy_value.X_add_number;
+ final_val += symp->sy_value.X_add_number;
else
- return 0;
+ final_val = 0;
+ return final_val;
}
resolved = 0;
resolved = 1;
}
+ final_val = 0;
final_seg = undefined_section;
goto exit_dont_set_value;
}
/* Fall through. */
case O_constant:
- final_val += symp->sy_frag->fr_address / OCTETS_PER_BYTE;
+ /* Symbols whose section has SEC_ELF_OCTETS set,
+ resolve to octets instead of target bytes. */
+ if (symp->bsym->section->flags & SEC_OCTETS)
+ final_val += symp->sy_frag->fr_address;
+ else
+ final_val += symp->sy_frag->fr_address / OCTETS_PER_BYTE;
if (final_seg == expr_section)
final_seg = absolute_section;
/* Fall through. */
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)
+ if (seg_left == undefined_section
+ || bfd_is_com_section (seg_left)
#if defined (OBJ_COFF) && defined (TE_PE)
|| S_IS_WEAK (add_symbol)
#endif
- || S_IS_COMMON (add_symbol))
+ || (finalize_syms
+ && ((final_seg == expr_section
+ && seg_left != expr_section
+ && seg_left != absolute_section)
+ || symbol_shadow_p (symp))))
{
if (finalize_syms)
{
symp->sy_value.X_op_symbol = add_symbol;
}
final_seg = seg_left;
- final_val = 0;
- resolved = symbol_resolved_p (add_symbol);
- symp->sy_flags.sy_resolving = 0;
- goto exit_dont_set_value;
- }
- else if (finalize_syms
- && ((final_seg == expr_section && seg_left != expr_section)
- || symbol_shadow_p (symp)))
- {
- /* If the symbol is an expression symbol, do similarly
- as for undefined and common syms above. Handles
- "sym +/- expr" where "expr" cannot be evaluated
- immediately, and we want relocations to be against
- "sym", eg. because it is weak. */
- symp->sy_value.X_op = O_symbol;
- symp->sy_value.X_add_symbol = add_symbol;
- symp->sy_value.X_add_number = final_val;
- symp->sy_value.X_op_symbol = add_symbol;
- final_seg = seg_left;
final_val += symp->sy_frag->fr_address + left;
resolved = symbol_resolved_p (add_symbol);
symp->sy_flags.sy_resolving = 0;
if (finalize_syms)
S_SET_VALUE (symp, final_val);
-exit_dont_set_value:
+ exit_dont_set_value:
/* Always set the segment, even if not finalizing the value.
The segment is used to determine whether a symbol is defined. */
S_SET_SEGMENT (symp, final_seg);
if ((flags & BSF_LOCAL) && (flags & BSF_GLOBAL))
abort ();
- if (bfd_get_section (s->bsym) == reg_section)
+ if (bfd_asymbol_section (s->bsym) == reg_section)
return 1;
if (flag_strip_local_absolute
/* Keep BSF_FILE symbols in order to allow debuggers to identify
the source file even when the object file is stripped. */
&& (flags & (BSF_GLOBAL | BSF_FILE)) == 0
- && bfd_get_section (s->bsym) == absolute_section)
+ && bfd_asymbol_section (s->bsym) == absolute_section)
return 1;
name = S_GET_NAME (s);
int
symbol_same_p (symbolS *s1, symbolS *s2)
{
- if (s1->sy_flags.sy_local_symbol
- && local_symbol_converted_p ((struct local_symbol *) s1))
- s1 = local_symbol_get_real_symbol ((struct local_symbol *) s1);
- if (s2->sy_flags.sy_local_symbol
- && local_symbol_converted_p ((struct local_symbol *) s2))
- s2 = local_symbol_get_real_symbol ((struct local_symbol *) s2);
+ s1 = get_real_sym (s1);
+ s2 = get_real_sym (s2);
return s1 == s2;
}
return s->sy_next == s;
}
+/* If S was created as a struct symbol, return S, otherwise if S is a
+ converted local_symbol return the converted symbol, otherwise
+ return NULL. */
+
+symbolS *
+symbol_symbolS (symbolS *s)
+{
+ if (LOCAL_SYMBOL_CHECK (s))
+ return NULL;
+ return s;
+}
+
/* Return the BFD symbol for a symbol. */
asymbol *
is defined as an expression or a plain value. */
if ( S_GET_SEGMENT (sym) == expr_section
|| S_GET_SEGMENT (sym) == absolute_section)
- return symbol_relc_make_expr (& sym->sy_value);
+ return symbol_relc_make_expr (symbol_get_value_expression (sym));
/* This may be a "fake symbol", referring to ".".
Write out a special null symbol to refer to this position. */