xref: /netbsd-src/external/gpl3/gdb/dist/bfd/elf32-d10v.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* D10V-specific support for 32-bit ELF
2    Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
3    2007, 2010, 2012 Free Software Foundation, Inc.
4    Contributed by Martin Hunt (hunt@cygnus.com).
5 
6    This file is part of BFD, the Binary File Descriptor library.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21    MA 02110-1301, USA.  */
22 
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27 #include "elf/d10v.h"
28 
29 /* Use REL instead of RELA to save space.  */
30 #define USE_REL	1
31 
32 static reloc_howto_type elf_d10v_howto_table[] =
33 {
34   /* This reloc does nothing.  */
35   HOWTO (R_D10V_NONE,		/* Type.  */
36 	 0,			/* Rightshift.  */
37 	 2,			/* Size (0 = byte, 1 = short, 2 = long).  */
38 	 32,			/* Bitsize.  */
39 	 FALSE,			/* PC_relative.  */
40 	 0,			/* Bitpos.  */
41 	 complain_overflow_dont,/* Complain_on_overflow.  */
42 	 bfd_elf_generic_reloc, /* Special_function.  */
43 	 "R_D10V_NONE",		/* Name.  */
44 	 FALSE,			/* Partial_inplace.  */
45 	 0,			/* Src_mask.  */
46 	 0,			/* Dst_mask.  */
47 	 FALSE),		/* PCrel_offset.  */
48 
49   /* An PC Relative 10-bit relocation, shifted by 2, right container.  */
50   HOWTO (R_D10V_10_PCREL_R,	/* Type.  */
51 	 2,	                /* Rightshift.  */
52 	 2,	                /* Size (0 = byte, 1 = short, 2 = long).  */
53 	 8,	                /* Bitsize.  */
54 	 TRUE,	        	/* PC_relative.  */
55 	 0,	                /* Bitpos.  */
56 	 complain_overflow_signed, /* Complain_on_overflow.  */
57 	 bfd_elf_generic_reloc, /* Special_function.  */
58 	 "R_D10V_10_PCREL_R",	/* Name.  */
59 	 FALSE,	        	/* Partial_inplace.  */
60 	 0xff,			/* Src_mask.  */
61 	 0xff,   		/* Dst_mask.  */
62 	 TRUE),			/* PCrel_offset.  */
63 
64   /* An PC Relative 10-bit relocation, shifted by 2, left container.  */
65   HOWTO (R_D10V_10_PCREL_L,	/* Type.  */
66 	 2,	                /* Rightshift.  */
67 	 2,	                /* Size (0 = byte, 1 = short, 2 = long).  */
68 	 8,	                /* Bitsize.  */
69 	 TRUE,	        	/* PC_relative.  */
70 	 15,	                /* Bitpos.  */
71 	 complain_overflow_signed, /* Complain_on_overflow.  */
72 	 bfd_elf_generic_reloc, /* Special_function.  */
73 	 "R_D10V_10_PCREL_L",	/* Name.  */
74 	 FALSE,	        	/* Partial_inplace.  */
75 	 0x07f8000,		/* Src_mask.  */
76 	 0x07f8000,   		/* Dst_mask.  */
77 	 TRUE),			/* PCrel_offset.  */
78 
79   /* A 16 bit absolute relocation.  */
80   HOWTO (R_D10V_16,		/* Type.  */
81 	 0,			/* Rightshift.  */
82 	 1,			/* Size (0 = byte, 1 = short, 2 = long).  */
83 	 16,			/* Bitsize.  */
84 	 FALSE,			/* PC_relative.  */
85 	 0,			/* Bitpos.  */
86 	 complain_overflow_dont,/* Complain_on_overflow.  */
87 	 bfd_elf_generic_reloc, /* Special_function.  */
88 	 "R_D10V_16",		/* Name.  */
89 	 FALSE,			/* Partial_inplace.  */
90 	 0xffff,		/* Src_mask.  */
91 	 0xffff,		/* Dst_mask.  */
92 	 FALSE),		/* PCrel_offset.  */
93 
94   /* An 18 bit absolute relocation, right shifted 2.  */
95   HOWTO (R_D10V_18,		/* Type.  */
96 	 2,			/* Rightshift.  */
97 	 1,			/* Size (0 = byte, 1 = short, 2 = long).  */
98 	 16,			/* Bitsize.  */
99 	 FALSE,			/* PC_relative.  */
100 	 0,			/* Bitpos.  */
101 	 complain_overflow_dont, /* Complain_on_overflow.  */
102 	 bfd_elf_generic_reloc, /* Special_function.  */
103 	 "R_D10V_18",		/* Name.  */
104 	 FALSE,			/* Partial_inplace.  */
105 	 0xffff,		/* Src_mask.  */
106 	 0xffff,		/* Dst_mask.  */
107 	 FALSE),		/* PCrel_offset.  */
108 
109   /* A relative 18 bit relocation, right shifted by 2.  */
110   HOWTO (R_D10V_18_PCREL,	/* Type.  */
111 	 2,			/* Rightshift.  */
112 	 2,			/* Size (0 = byte, 1 = short, 2 = long).  */
113 	 16,			/* Bitsize.  */
114 	 TRUE,			/* PC_relative.  */
115 	 0,			/* Bitpos.  */
116 	 complain_overflow_signed, /* Complain_on_overflow.  */
117 	 bfd_elf_generic_reloc, /* Special_function.  */
118 	 "R_D10V_18_PCREL",	/* Name.  */
119 	 FALSE,			/* Partial_inplace.  */
120 	 0xffff,		/* Src_mask.  */
121 	 0xffff,		/* Dst_mask.  */
122 	 TRUE),			/* PCrel_offset.  */
123 
124   /* A 32 bit absolute relocation.  */
125   HOWTO (R_D10V_32,		/* Type.  */
126 	 0,			/* Rightshift.  */
127 	 2,			/* Size (0 = byte, 1 = short, 2 = long).  */
128 	 32,			/* Bitsize.  */
129 	 FALSE,			/* PC_relative.  */
130 	 0,			/* Bitpos.  */
131 	 complain_overflow_dont,/* Complain_on_overflow.  */
132 	 bfd_elf_generic_reloc, /* Special_function.  */
133 	 "R_D10V_32",		/* Name.  */
134 	 FALSE,			/* Partial_inplace.  */
135 	 0xffffffff,		/* Src_mask.  */
136 	 0xffffffff,		/* Dst_mask.  */
137 	 FALSE),		/* PCrel_offset.  */
138 
139   /* GNU extension to record C++ vtable hierarchy.  */
140   HOWTO (R_D10V_GNU_VTINHERIT,	/* Type.  */
141 	 0,                     /* Rightshift.  */
142 	 2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
143 	 0,                     /* Bitsize.  */
144 	 FALSE,                 /* PC_relative.  */
145 	 0,                     /* Bitpos.  */
146 	 complain_overflow_dont,/* Complain_on_overflow.  */
147 	 NULL,                  /* Special_function.  */
148 	 "R_D10V_GNU_VTINHERIT",/* Name.  */
149 	 FALSE,                 /* Partial_inplace.  */
150 	 0,                     /* Src_mask.  */
151 	 0,                     /* Dst_mask.  */
152 	 FALSE),                /* PCrel_offset.  */
153 
154   /* GNU extension to record C++ vtable member usage.  */
155   HOWTO (R_D10V_GNU_VTENTRY,    /* Type.  */
156 	 0,                     /* Rightshift.  */
157 	 2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
158 	 0,                     /* Bitsize.  */
159 	 FALSE,                 /* PC_relative.  */
160 	 0,                     /* Bitpos.  */
161 	 complain_overflow_dont,/* Complain_on_overflow.  */
162 	 _bfd_elf_rel_vtable_reloc_fn,  /* Special_function.  */
163 	 "R_D10V_GNU_VTENTRY",  /* Name.  */
164 	 FALSE,                 /* Partial_inplace.  */
165 	 0,                     /* Src_mask.  */
166 	 0,                     /* Dst_mask.  */
167 	 FALSE),                /* PCrel_offset.  */
168 };
169 
170 /* Map BFD reloc types to D10V ELF reloc types.  */
171 
172 struct d10v_reloc_map
173 {
174   bfd_reloc_code_real_type bfd_reloc_val;
175   unsigned char elf_reloc_val;
176 };
177 
178 static const struct d10v_reloc_map d10v_reloc_map[] =
179 {
180   { BFD_RELOC_NONE, R_D10V_NONE, },
181   { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
182   { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
183   { BFD_RELOC_16, R_D10V_16 },
184   { BFD_RELOC_D10V_18, R_D10V_18 },
185   { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
186   { BFD_RELOC_32, R_D10V_32 },
187   { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
188   { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
189 };
190 
191 static reloc_howto_type *
192 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
193 				 bfd_reloc_code_real_type code)
194 {
195   unsigned int i;
196 
197   for (i = 0;
198        i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
199        i++)
200     if (d10v_reloc_map[i].bfd_reloc_val == code)
201       return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val];
202 
203   return NULL;
204 }
205 
206 static reloc_howto_type *
207 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
208 				 const char *r_name)
209 {
210   unsigned int i;
211 
212   for (i = 0;
213        i < sizeof (elf_d10v_howto_table) / sizeof (elf_d10v_howto_table[0]);
214        i++)
215     if (elf_d10v_howto_table[i].name != NULL
216 	&& strcasecmp (elf_d10v_howto_table[i].name, r_name) == 0)
217       return &elf_d10v_howto_table[i];
218 
219   return NULL;
220 }
221 
222 /* Set the howto pointer for an D10V ELF reloc.  */
223 
224 static void
225 d10v_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
226 			arelent *cache_ptr,
227 			Elf_Internal_Rela *dst)
228 {
229   unsigned int r_type;
230 
231   r_type = ELF32_R_TYPE (dst->r_info);
232   BFD_ASSERT (r_type < (unsigned int) R_D10V_max);
233   cache_ptr->howto = &elf_d10v_howto_table[r_type];
234 }
235 
236 static asection *
237 elf32_d10v_gc_mark_hook (asection *sec,
238 			 struct bfd_link_info *info,
239 			 Elf_Internal_Rela *rel,
240 			 struct elf_link_hash_entry *h,
241 			 Elf_Internal_Sym *sym)
242 {
243   if (h != NULL)
244     switch (ELF32_R_TYPE (rel->r_info))
245       {
246       case R_D10V_GNU_VTINHERIT:
247       case R_D10V_GNU_VTENTRY:
248 	return NULL;
249       }
250 
251   return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
252 }
253 
254 /* Look through the relocs for a section during the first phase.
255    Since we don't do .gots or .plts, we just need to consider the
256    virtual table relocs for gc.  */
257 
258 static bfd_boolean
259 elf32_d10v_check_relocs (bfd *abfd,
260 			 struct bfd_link_info *info,
261 			 asection *sec,
262 			 const Elf_Internal_Rela *relocs)
263 {
264   Elf_Internal_Shdr *symtab_hdr;
265   struct elf_link_hash_entry **sym_hashes;
266   const Elf_Internal_Rela *rel;
267   const Elf_Internal_Rela *rel_end;
268 
269   if (info->relocatable)
270     return TRUE;
271 
272   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
273   sym_hashes = elf_sym_hashes (abfd);
274 
275   rel_end = relocs + sec->reloc_count;
276   for (rel = relocs; rel < rel_end; rel++)
277     {
278       struct elf_link_hash_entry *h;
279       unsigned long r_symndx;
280 
281       r_symndx = ELF32_R_SYM (rel->r_info);
282       if (r_symndx < symtab_hdr->sh_info)
283         h = NULL;
284       else
285 	{
286 	  h = sym_hashes[r_symndx - symtab_hdr->sh_info];
287 	  while (h->root.type == bfd_link_hash_indirect
288 		 || h->root.type == bfd_link_hash_warning)
289 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
290 
291 	  /* PR15323, ref flags aren't set for references in the same
292 	     object.  */
293 	  h->root.non_ir_ref = 1;
294 	}
295 
296       switch (ELF32_R_TYPE (rel->r_info))
297         {
298         /* This relocation describes the C++ object vtable hierarchy.
299            Reconstruct it for later use during GC.  */
300         case R_D10V_GNU_VTINHERIT:
301           if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
302             return FALSE;
303           break;
304 
305         /* This relocation describes which C++ vtable entries are actually
306            used.  Record for later use during GC.  */
307         case R_D10V_GNU_VTENTRY:
308           BFD_ASSERT (h != NULL);
309           if (h != NULL
310               && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
311             return FALSE;
312           break;
313         }
314     }
315 
316   return TRUE;
317 }
318 
319 static bfd_vma
320 extract_rel_addend (bfd *abfd,
321 		    bfd_byte *where,
322 		    reloc_howto_type *howto)
323 {
324   bfd_vma insn, val;
325 
326   switch (howto->size)
327     {
328     case 0:
329       insn = bfd_get_8 (abfd, where);
330       break;
331     case 1:
332       insn = bfd_get_16 (abfd, where);
333       break;
334     case 2:
335       insn = bfd_get_32 (abfd, where);
336       break;
337     default:
338       abort ();
339     }
340 
341   val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
342   /* We should really be testing for signed addends here, but we don't
343      have that info directly in the howto.  */
344   if (howto->pc_relative)
345     {
346       bfd_vma sign;
347       sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
348       sign = sign >> howto->bitpos << howto->rightshift;
349       val = (val ^ sign) - sign;
350     }
351   return val;
352 }
353 
354 static void
355 insert_rel_addend (bfd *abfd,
356 		   bfd_byte *where,
357 		   reloc_howto_type *howto,
358 		   bfd_vma addend)
359 {
360   bfd_vma insn;
361 
362   addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
363   insn = ~howto->dst_mask;
364   switch (howto->size)
365     {
366     case 0:
367       insn &= bfd_get_8 (abfd, where);
368       insn |= addend;
369       bfd_put_8 (abfd, insn, where);
370       break;
371     case 1:
372       insn &= bfd_get_16 (abfd, where);
373       insn |= addend;
374       bfd_put_16 (abfd, insn, where);
375       break;
376     case 2:
377       insn &= bfd_get_32 (abfd, where);
378       insn |= addend;
379       bfd_put_32 (abfd, insn, where);
380       break;
381     default:
382       abort ();
383     }
384 }
385 
386 /* Relocate a D10V ELF section.  */
387 
388 static bfd_boolean
389 elf32_d10v_relocate_section (bfd *output_bfd,
390 			     struct bfd_link_info *info,
391 			     bfd *input_bfd,
392 			     asection *input_section,
393 			     bfd_byte *contents,
394 			     Elf_Internal_Rela *relocs,
395 			     Elf_Internal_Sym *local_syms,
396 			     asection **local_sections)
397 {
398   Elf_Internal_Shdr *symtab_hdr;
399   struct elf_link_hash_entry **sym_hashes;
400   Elf_Internal_Rela *rel, *relend;
401   const char *name;
402 
403   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
404   sym_hashes = elf_sym_hashes (input_bfd);
405 
406   rel = relocs;
407   relend = relocs + input_section->reloc_count;
408   for (; rel < relend; rel++)
409     {
410       int r_type;
411       reloc_howto_type *howto;
412       unsigned long r_symndx;
413       Elf_Internal_Sym *sym;
414       asection *sec;
415       struct elf_link_hash_entry *h;
416       bfd_vma relocation;
417       bfd_reloc_status_type r;
418 
419       r_symndx = ELF32_R_SYM (rel->r_info);
420       r_type = ELF32_R_TYPE (rel->r_info);
421 
422       if (r_type == R_D10V_GNU_VTENTRY
423           || r_type == R_D10V_GNU_VTINHERIT)
424         continue;
425 
426       howto = elf_d10v_howto_table + r_type;
427       h = NULL;
428       sym = NULL;
429       sec = NULL;
430       if (r_symndx < symtab_hdr->sh_info)
431 	{
432 	  sym = local_syms + r_symndx;
433 	  sec = local_sections[r_symndx];
434 	  relocation = (sec->output_section->vma
435 			+ sec->output_offset
436 			+ sym->st_value);
437 	  if (ELF_ST_TYPE (sym->st_info) == STT_SECTION
438 	      && ((sec->flags & SEC_MERGE) != 0
439 		  || (info->relocatable
440 		      && sec->output_offset != 0)))
441 	    {
442 	      bfd_vma addend;
443 	      bfd_byte *where = contents + rel->r_offset;
444 
445 	      addend = extract_rel_addend (input_bfd, where, howto);
446 
447 	      if (info->relocatable)
448 		addend += sec->output_offset;
449 	      else
450 		{
451 		  asection *msec = sec;
452 		  addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec,
453 						   addend);
454 		  addend -= relocation;
455 		  addend += msec->output_section->vma + msec->output_offset;
456 		}
457 	      insert_rel_addend (input_bfd, where, howto, addend);
458 	    }
459 	}
460       else
461 	{
462 	  bfd_boolean unresolved_reloc, warned, ignored;
463 
464 	  RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
465 				   r_symndx, symtab_hdr, sym_hashes,
466 				   h, sec, relocation,
467 				   unresolved_reloc, warned, ignored);
468 	}
469 
470       if (sec != NULL && discarded_section (sec))
471 	RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
472 					 rel, 1, relend, howto, 0, contents);
473 
474       if (info->relocatable)
475 	continue;
476 
477       if (h != NULL)
478 	name = h->root.root.string;
479       else
480 	{
481 	  name = (bfd_elf_string_from_elf_section
482 		  (input_bfd, symtab_hdr->sh_link, sym->st_name));
483 	  if (name == NULL || *name == '\0')
484 	    name = bfd_section_name (input_bfd, sec);
485 	}
486 
487       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
488                                     contents, rel->r_offset,
489                                     relocation, (bfd_vma) 0);
490 
491       if (r != bfd_reloc_ok)
492 	{
493 	  const char * msg = (const char *) 0;
494 
495 	  switch (r)
496 	    {
497 	    case bfd_reloc_overflow:
498 	      if (!((*info->callbacks->reloc_overflow)
499 		    (info, (h ? &h->root : NULL), name, howto->name,
500 		     (bfd_vma) 0, input_bfd, input_section,
501 		     rel->r_offset)))
502 		return FALSE;
503 	      break;
504 
505 	    case bfd_reloc_undefined:
506 	      if (!((*info->callbacks->undefined_symbol)
507 		    (info, name, input_bfd, input_section,
508 		     rel->r_offset, TRUE)))
509 		return FALSE;
510 	      break;
511 
512 	    case bfd_reloc_outofrange:
513 	      msg = _("internal error: out of range error");
514 	      goto common_error;
515 
516 	    case bfd_reloc_notsupported:
517 	      msg = _("internal error: unsupported relocation error");
518 	      goto common_error;
519 
520 	    case bfd_reloc_dangerous:
521 	      msg = _("internal error: dangerous error");
522 	      goto common_error;
523 
524 	    default:
525 	      msg = _("internal error: unknown error");
526 	      /* fall through */
527 
528 	    common_error:
529 	      if (!((*info->callbacks->warning)
530 		    (info, msg, name, input_bfd, input_section,
531 		     rel->r_offset)))
532 		return FALSE;
533 	      break;
534 	    }
535 	}
536     }
537 
538   return TRUE;
539 }
540 #define ELF_ARCH		bfd_arch_d10v
541 #define ELF_MACHINE_CODE	EM_D10V
542 #define ELF_MACHINE_ALT1	EM_CYGNUS_D10V
543 #define ELF_MAXPAGESIZE		0x1000
544 
545 #define TARGET_BIG_SYM          bfd_elf32_d10v_vec
546 #define TARGET_BIG_NAME		"elf32-d10v"
547 
548 #define elf_info_to_howto	             0
549 #define elf_info_to_howto_rel	             d10v_info_to_howto_rel
550 #define elf_backend_object_p	             0
551 #define elf_backend_final_write_processing   0
552 #define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
553 #define elf_backend_check_relocs             elf32_d10v_check_relocs
554 #define elf_backend_relocate_section         elf32_d10v_relocate_section
555 #define elf_backend_can_gc_sections          1
556 
557 #include "elf32-target.h"
558