95 lines
3.1 KiB
C
95 lines
3.1 KiB
C
/* as.c - GAS literal pool management.
|
|
Copyright 1994, 2000 Free Software Foundation, Inc.
|
|
Written by Ken Raeburn (raeburn@cygnus.com).
|
|
|
|
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. */
|
|
|
|
/* This isn't quite a "constant" pool. Some of the values may get
|
|
adjusted at run time, e.g., for symbolic relocations when shared
|
|
libraries are in use. It's more of a "literal" pool.
|
|
|
|
On the Alpha, this should be used for .lita and .lit8. (Is there
|
|
ever a .lit4?) On the MIPS, it could be used for .lit4 as well.
|
|
|
|
The expressions passed here should contain either constants or symbols,
|
|
not a combination of both. Typically, the constant pool is accessed
|
|
with some sort of GP register, so the size of the pool must be kept down
|
|
if possible. The exception is section offsets -- if you're storing a
|
|
pointer to the start of .data, for example, and your machine provides
|
|
for 16-bit signed addends, you might want to store .data+32K, so that
|
|
you can access all of the first 64K of .data with the one pointer.
|
|
|
|
This isn't a requirement, just a guideline that can help keep .o file
|
|
size down. */
|
|
|
|
#include "as.h"
|
|
#include "subsegs.h"
|
|
|
|
#if defined (BFD_ASSEMBLER) && defined (NEED_LITERAL_POOL)
|
|
|
|
valueT
|
|
add_to_literal_pool (sym, addend, sec, size)
|
|
symbolS *sym;
|
|
valueT addend;
|
|
segT sec;
|
|
int size;
|
|
{
|
|
segT current_section = now_seg;
|
|
int current_subsec = now_subseg;
|
|
valueT offset;
|
|
bfd_reloc_code_real_type reloc_type;
|
|
char *p;
|
|
segment_info_type *seginfo = seg_info (sec);
|
|
fixS *fixp;
|
|
|
|
offset = 0;
|
|
/* @@ This assumes all entries in a given section will be of the same
|
|
size... Probably correct, but unwise to rely on. */
|
|
/* This must always be called with the same subsegment. */
|
|
if (seginfo->frchainP)
|
|
for (fixp = seginfo->frchainP->fix_root;
|
|
fixp != (fixS *) NULL;
|
|
fixp = fixp->fx_next, offset += size)
|
|
{
|
|
if (fixp->fx_addsy == sym && fixp->fx_offset == addend)
|
|
return offset;
|
|
}
|
|
|
|
subseg_set (sec, 0);
|
|
p = frag_more (size);
|
|
memset (p, 0, size);
|
|
|
|
switch (size)
|
|
{
|
|
case 4:
|
|
reloc_type = BFD_RELOC_32;
|
|
break;
|
|
case 8:
|
|
reloc_type = BFD_RELOC_64;
|
|
break;
|
|
default:
|
|
abort ();
|
|
}
|
|
fix_new (frag_now, p - frag_now->fr_literal, size, sym, addend, 0,
|
|
reloc_type);
|
|
|
|
subseg_set (current_section, current_subsec);
|
|
offset = seginfo->literal_pool_size;
|
|
seginfo->literal_pool_size += size;
|
|
return offset;
|
|
}
|
|
#endif /* BFD_ASSEMBLER */
|