| /* literal.c - GAS literal pool management. |
| Copyright (C) 1994-2016 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 3, 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, 51 Franklin Street - Fifth Floor, |
| Boston, MA 02110-1301, 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" |
| |
| #ifdef NEED_LITERAL_POOL |
| |
| valueT |
| add_to_literal_pool (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 |