/* Remember the value of dot when parsing expressions. */
addressT dot_value;
+/* Relocs generated by ".reloc" pseudo. */
+struct reloc_list* reloc_list;
+
void print_fixup (fixS *);
/* We generally attach relocs to frag chains. However, after we have
#define EMIT_SECTION_SYMBOLS 1
#endif
+/* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
+ and check for validity. Convert RELOC_LIST from using U.A fields
+ to U.B fields. */
+static void
+resolve_reloc_expr_symbols (void)
+{
+ struct reloc_list *r;
+
+ for (r = reloc_list; r; r = r->next)
+ {
+ expressionS *symval;
+ symbolS *sym;
+ bfd_vma offset, addend;
+ asection *sec;
+ reloc_howto_type *howto;
+
+ resolve_symbol_value (r->u.a.offset_sym);
+ symval = symbol_get_value_expression (r->u.a.offset_sym);
+
+ offset = 0;
+ sym = NULL;
+ if (symval->X_op == O_constant)
+ sym = r->u.a.offset_sym;
+ else if (symval->X_op == O_symbol)
+ {
+ sym = symval->X_add_symbol;
+ offset = symval->X_add_number;
+ symval = symbol_get_value_expression (symval->X_add_symbol);
+ }
+ if (sym == NULL
+ || symval->X_op != O_constant
+ || (sec = S_GET_SEGMENT (sym)) == NULL
+ || !SEG_NORMAL (sec))
+ {
+ as_bad_where (r->file, r->line, _("invalid offset expression"));
+ sec = NULL;
+ }
+ else
+ offset += S_GET_VALUE (sym);
+
+ sym = NULL;
+ addend = r->u.a.addend;
+ if (r->u.a.sym != NULL)
+ {
+ resolve_symbol_value (r->u.a.sym);
+ symval = symbol_get_value_expression (r->u.a.sym);
+ if (symval->X_op == O_constant)
+ sym = r->u.a.sym;
+ else if (symval->X_op == O_symbol)
+ {
+ sym = symval->X_add_symbol;
+ addend += symval->X_add_number;
+ symval = symbol_get_value_expression (symval->X_add_symbol);
+ }
+ if (symval->X_op != O_constant)
+ {
+ as_bad_where (r->file, r->line, _("invalid reloc expression"));
+ sec = NULL;
+ }
+ else if (sym != NULL)
+ symbol_mark_used_in_reloc (sym);
+ }
+ if (sym == NULL)
+ {
+ if (abs_section_sym == NULL)
+ abs_section_sym = section_symbol (absolute_section);
+ sym = abs_section_sym;
+ }
+
+ howto = r->u.a.howto;
+
+ r->u.b.sec = sec;
+ r->u.b.s = symbol_get_bfdsym (sym);
+ r->u.b.r.sym_ptr_ptr = &r->u.b.s;
+ r->u.b.r.address = offset;
+ r->u.b.r.addend = addend;
+ r->u.b.r.howto = howto;
+ }
+}
+
/* This pass over fixups decides whether symbols can be replaced with
section symbols. */
segment_info_type *seginfo = seg_info (sec);
unsigned int i;
unsigned int n;
+ struct reloc_list *my_reloc_list, **rp, *r;
arelent **relocs;
fixS *fixp;
n *= MAX_RELOC_EXPANSION;
#endif
+ /* Extract relocs for this section from reloc_list. */
+ rp = &reloc_list;
+ my_reloc_list = NULL;
+ while ((r = *rp) != NULL)
+ {
+ if (r->u.b.sec == sec)
+ {
+ *rp = r->next;
+ r->next = my_reloc_list;
+ my_reloc_list = r;
+ n++;
+ }
+ else
+ rp = &r->next;
+ }
+
relocs = xcalloc (n, sizeof (arelent *));
i = 0;
}
#endif
+ for (r = my_reloc_list; r != NULL; r = r->next)
+ {
+ fragS *f;
+ for (f = seginfo->frchainP->frch_root; f; f = f->fr_next)
+ if (f->fr_address <= r->u.b.r.address
+ && r->u.b.r.address < f->fr_address + f->fr_fix)
+ break;
+ if (f == NULL)
+ as_bad_where (r->file, r->line,
+ _("reloc not within (fixed part of) section"));
+ else
+ {
+ relocs[n++] = &r->u.b.r;
+ install_reloc (sec, &r->u.b.r, f, r->file, r->line);
+ }
+ }
+
if (n)
{
flagword flags = bfd_get_section_flags (abfd, sec);
resolve_symbol_value (symp);
}
resolve_local_symbol_values ();
+ resolve_reloc_expr_symbols ();
PROGRESS (1);
/* Do relax(). */
{
unsigned long max_iterations;
- offsetT stretch; /* May be any size, 0 or negative. */
- /* Cumulative number of addresses we have relaxed this pass.
- We may have relaxed more than one address. */
- int stretched; /* Have we stretched on this pass? */
- /* This is 'cuz stretch may be zero, when, in fact some piece of code
- grew, and another shrank. If a branch instruction doesn't fit anymore,
- we could be scrod. */
+
+ /* Cumulative address adjustment. */
+ offsetT stretch;
+
+ /* Have we made any adjustment this pass? We can't just test
+ stretch because one piece of code may have grown and another
+ shrank. */
+ int stretched;
+
+ /* Most horrible, but gcc may give us some exception data that
+ is impossible to assemble, of the form
+
+ .align 4
+ .byte 0, 0
+ .uleb128 end - start
+ start:
+ .space 128*128 - 1
+ .align 4
+ end:
+
+ If the leb128 is two bytes in size, then end-start is 128*128,
+ which requires a three byte leb128. If the leb128 is three
+ bytes in size, then end-start is 128*128-1, which requires a
+ two byte leb128. We work around this dilemma by inserting
+ an extra 4 bytes of alignment just after the .align. This
+ works because the data after the align is accessed relative to
+ the end label.
+
+ This counter is used in a tiny state machine to detect
+ whether a leb128 followed by an align is impossible to
+ relax. */
+ int rs_leb128_fudge = 0;
/* We want to prevent going into an infinite loop where one frag grows
depending upon the location of a symbol which is in turn moved by
}
growth = newoff - oldoff;
+
+ /* If this align happens to follow a leb128 and
+ we have determined that the leb128 is bouncing
+ in size, then break the cycle by inserting an
+ extra alignment. */
+ if (growth < 0
+ && (rs_leb128_fudge & 16) != 0
+ && (rs_leb128_fudge & 15) >= 2)
+ {
+ segment_info_type *seginfo = seg_info (segment);
+ struct obstack *ob = &seginfo->frchainP->frch_obstack;
+ struct frag *newf;
+
+ newf = frag_alloc (ob);
+ obstack_blank_fast (ob, fragP->fr_var);
+ obstack_finish (ob);
+ memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
+ memcpy (newf->fr_literal,
+ fragP->fr_literal + fragP->fr_fix,
+ fragP->fr_var);
+ newf->fr_type = rs_fill;
+ newf->fr_fix = 0;
+ newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
+ / fragP->fr_var);
+ if (newf->fr_offset * newf->fr_var
+ != (offsetT) 1 << fragP->fr_offset)
+ {
+ newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
+ newf->fr_var = 1;
+ }
+ /* Include growth of new frag, because rs_fill
+ frags don't normally grow. */
+ growth += newf->fr_offset * newf->fr_var;
+ /* The new frag address is newoff. Adjust this
+ for the amount we'll add when we process the
+ new frag. */
+ newf->fr_address = newoff - stretch - growth;
+ newf->relax_marker ^= 1;
+ fragP->fr_next = newf;
+#ifdef DEBUG
+ as_warn (_("padding added"));
+#endif
+ }
}
break;
{
stretch += growth;
stretched = 1;
+ if (fragP->fr_type == rs_leb128)
+ rs_leb128_fudge += 16;
+ else if (fragP->fr_type == rs_align
+ && (rs_leb128_fudge & 16) != 0
+ && stretch == 0)
+ rs_leb128_fudge += 16;
+ else
+ rs_leb128_fudge = 0;
}
}
+
+ if (stretch == 0
+ && (rs_leb128_fudge & 16) == 0
+ && (rs_leb128_fudge & -16) != 0)
+ rs_leb128_fudge += 1;
+ else
+ rs_leb128_fudge = 0;
}
/* Until nothing further to relax. */
while (stretched && -- max_iterations);