1 /* Ubicom IP2xxx specific support for 32-bit ELF
2    Copyright (C) 2000-2021 Free Software Foundation, Inc.
3 
4    This file is part of BFD, the Binary File Descriptor library.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19    MA 02110-1301, USA.  */
20 
21 #include "sysdep.h"
22 #include "bfd.h"
23 #include "libbfd.h"
24 #include "elf-bfd.h"
25 #include "elf/ip2k.h"
26 
27 /* Struct used to pass miscellaneous paramaters which
28    helps to avoid overly long parameter lists.  */
29 struct misc
30 {
31   Elf_Internal_Shdr *  symtab_hdr;
32   Elf_Internal_Rela *  irelbase;
33   bfd_byte *	       contents;
34   Elf_Internal_Sym *   isymbuf;
35 };
36 
37 struct ip2k_opcode
38 {
39   unsigned short opcode;
40   unsigned short mask;
41 };
42 
43 static bool ip2k_relaxed = false;
44 
45 static const struct ip2k_opcode ip2k_page_opcode[] =
46 {
47   {0x0010, 0xFFF8},	/* Page.  */
48   {0x0000, 0x0000},
49 };
50 
51 #define IS_PAGE_OPCODE(code) \
52   ip2k_is_opcode (code, ip2k_page_opcode)
53 
54 static const struct ip2k_opcode ip2k_jmp_opcode[] =
55 {
56   {0xE000, 0xE000},	/* Jmp.  */
57   {0x0000, 0x0000},
58 };
59 
60 #define IS_JMP_OPCODE(code) \
61   ip2k_is_opcode (code, ip2k_jmp_opcode)
62 
63 static const struct ip2k_opcode ip2k_snc_opcode[] =
64 {
65   {0xA00B, 0xFFFF},	/* Snc.  */
66   {0x0000, 0x0000},
67 };
68 
69 #define IS_SNC_OPCODE(code) \
70   ip2k_is_opcode (code, ip2k_snc_opcode)
71 
72 static const struct ip2k_opcode ip2k_inc_1sp_opcode[] =
73 {
74   {0x2B81, 0xFFFF},	/* Inc 1(SP).  */
75   {0x0000, 0x0000},
76 };
77 
78 #define IS_INC_1SP_OPCODE(code) \
79   ip2k_is_opcode (code, ip2k_inc_1sp_opcode)
80 
81 static const struct ip2k_opcode ip2k_add_2sp_w_opcode[] =
82 {
83   {0x1F82, 0xFFFF},	/* Add 2(SP),w.  */
84   {0x0000, 0x0000},
85 };
86 
87 #define IS_ADD_2SP_W_OPCODE(code) \
88   ip2k_is_opcode (code, ip2k_add_2sp_w_opcode)
89 
90 static const struct ip2k_opcode ip2k_add_w_wreg_opcode[] =
91 {
92   {0x1C0A, 0xFFFF},	/* Add w,wreg.  */
93   {0x1E0A, 0xFFFF},	/* Add wreg,w.  */
94   {0x0000, 0x0000},
95 };
96 
97 #define IS_ADD_W_WREG_OPCODE(code) \
98   ip2k_is_opcode (code, ip2k_add_w_wreg_opcode)
99 
100 static const struct ip2k_opcode ip2k_add_pcl_w_opcode[] =
101 {
102   {0x1E09, 0xFFFF},	/* Add pcl,w.  */
103   {0x0000, 0x0000},
104 };
105 
106 #define IS_ADD_PCL_W_OPCODE(code) \
107   ip2k_is_opcode (code, ip2k_add_pcl_w_opcode)
108 
109 static const struct ip2k_opcode ip2k_skip_opcodes[] =
110 {
111   {0xB000, 0xF000},	/* sb */
112   {0xA000, 0xF000},	/* snb */
113   {0x7600, 0xFE00},	/* cse/csne #lit */
114   {0x5800, 0xFC00},	/* incsnz */
115   {0x4C00, 0xFC00},	/* decsnz */
116   {0x4000, 0xFC00},	/* cse/csne */
117   {0x3C00, 0xFC00},	/* incsz */
118   {0x2C00, 0xFC00},	/* decsz */
119   {0x0000, 0x0000},
120 };
121 
122 #define IS_SKIP_OPCODE(code) \
123   ip2k_is_opcode (code, ip2k_skip_opcodes)
124 
125 /* Relocation tables.  */
126 static reloc_howto_type ip2k_elf_howto_table [] =
127 {
128 #define IP2K_HOWTO(t,rs,s,bs,pr,bp,name,sm,dm) \
129     HOWTO(t,			/* type */ \
130 	  rs,			/* rightshift */ \
131 	  s,			/* size (0 = byte, 1 = short, 2 = long) */ \
132 	  bs,			/* bitsize */ \
133 	  pr,			/* pc_relative */ \
134 	  bp,			/* bitpos */ \
135 	  complain_overflow_dont,/* complain_on_overflow */ \
136 	  bfd_elf_generic_reloc,/* special_function */ \
137 	  name,			/* name */ \
138 	  false,		/* partial_inplace */ \
139 	  sm,			/* src_mask */ \
140 	  dm,			/* dst_mask */ \
141 	  pr)			/* pcrel_offset */
142 
143   /* This reloc does nothing.  */
144   IP2K_HOWTO (R_IP2K_NONE, 0,3,0, false, 0, "R_IP2K_NONE", 0, 0),
145   /* A 16 bit absolute relocation.  */
146   IP2K_HOWTO (R_IP2K_16, 0,1,16, false, 0, "R_IP2K_16", 0, 0xffff),
147   /* A 32 bit absolute relocation.  */
148   IP2K_HOWTO (R_IP2K_32, 0,2,32, false, 0, "R_IP2K_32", 0, 0xffffffff),
149   /* A 8-bit data relocation for the FR9 field.  Ninth bit is computed specially.  */
150   IP2K_HOWTO (R_IP2K_FR9, 0,1,9, false, 0, "R_IP2K_FR9", 0, 0x00ff),
151   /* A 4-bit data relocation.  */
152   IP2K_HOWTO (R_IP2K_BANK, 8,1,4, false, 0, "R_IP2K_BANK", 0, 0x000f),
153   /* A 13-bit insn relocation - word address => right-shift 1 bit extra.  */
154   IP2K_HOWTO (R_IP2K_ADDR16CJP, 1,1,13, false, 0, "R_IP2K_ADDR16CJP", 0, 0x1fff),
155   /* A 3-bit insn relocation - word address => right-shift 1 bit extra.  */
156   IP2K_HOWTO (R_IP2K_PAGE3, 14,1,3, false, 0, "R_IP2K_PAGE3", 0, 0x0007),
157   /* Two 8-bit data relocations.  */
158   IP2K_HOWTO (R_IP2K_LO8DATA, 0,1,8, false, 0, "R_IP2K_LO8DATA", 0, 0x00ff),
159   IP2K_HOWTO (R_IP2K_HI8DATA, 8,1,8, false, 0, "R_IP2K_HI8DATA", 0, 0x00ff),
160   /* Two 8-bit insn relocations.  word address => right-shift 1 bit extra.  */
161   IP2K_HOWTO (R_IP2K_LO8INSN, 1,1,8, false, 0, "R_IP2K_LO8INSN", 0, 0x00ff),
162   IP2K_HOWTO (R_IP2K_HI8INSN, 9,1,8, false, 0, "R_IP2K_HI8INSN", 0, 0x00ff),
163 
164   /* Special 1 bit relocation for SKIP instructions.  */
165   IP2K_HOWTO (R_IP2K_PC_SKIP, 1,1,1, false, 12, "R_IP2K_PC_SKIP", 0xfffe, 0x1000),
166   /* 16 bit word address.  */
167   IP2K_HOWTO (R_IP2K_TEXT, 1,1,16, false, 0, "R_IP2K_TEXT", 0, 0xffff),
168   /* A 7-bit offset relocation for the FR9 field.  Eigth and ninth bit comes from insn.  */
169   IP2K_HOWTO (R_IP2K_FR_OFFSET, 0,1,9, false, 0, "R_IP2K_FR_OFFSET", 0x180, 0x007f),
170   /* Bits 23:16 of an address.  */
171   IP2K_HOWTO (R_IP2K_EX8DATA, 16,1,8, false, 0, "R_IP2K_EX8DATA", 0, 0x00ff),
172 };
173 
174 
175 /* Map BFD reloc types to IP2K ELF reloc types.  */
176 
177 static reloc_howto_type *
ip2k_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)178 ip2k_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
179 			bfd_reloc_code_real_type code)
180 {
181   /* Note that the ip2k_elf_howto_table is indxed by the R_
182      constants.  Thus, the order that the howto records appear in the
183      table *must* match the order of the relocation types defined in
184      include/elf/ip2k.h.  */
185 
186   switch (code)
187     {
188     case BFD_RELOC_NONE:
189       return &ip2k_elf_howto_table[ (int) R_IP2K_NONE];
190     case BFD_RELOC_16:
191       return &ip2k_elf_howto_table[ (int) R_IP2K_16];
192     case BFD_RELOC_32:
193       return &ip2k_elf_howto_table[ (int) R_IP2K_32];
194     case BFD_RELOC_IP2K_FR9:
195       return &ip2k_elf_howto_table[ (int) R_IP2K_FR9];
196     case BFD_RELOC_IP2K_BANK:
197       return &ip2k_elf_howto_table[ (int) R_IP2K_BANK];
198     case BFD_RELOC_IP2K_ADDR16CJP:
199       return &ip2k_elf_howto_table[ (int) R_IP2K_ADDR16CJP];
200     case BFD_RELOC_IP2K_PAGE3:
201       return &ip2k_elf_howto_table[ (int) R_IP2K_PAGE3];
202     case BFD_RELOC_IP2K_LO8DATA:
203       return &ip2k_elf_howto_table[ (int) R_IP2K_LO8DATA];
204     case BFD_RELOC_IP2K_HI8DATA:
205       return &ip2k_elf_howto_table[ (int) R_IP2K_HI8DATA];
206     case BFD_RELOC_IP2K_LO8INSN:
207       return &ip2k_elf_howto_table[ (int) R_IP2K_LO8INSN];
208     case BFD_RELOC_IP2K_HI8INSN:
209       return &ip2k_elf_howto_table[ (int) R_IP2K_HI8INSN];
210     case BFD_RELOC_IP2K_PC_SKIP:
211       return &ip2k_elf_howto_table[ (int) R_IP2K_PC_SKIP];
212     case BFD_RELOC_IP2K_TEXT:
213       return &ip2k_elf_howto_table[ (int) R_IP2K_TEXT];
214     case BFD_RELOC_IP2K_FR_OFFSET:
215       return &ip2k_elf_howto_table[ (int) R_IP2K_FR_OFFSET];
216     case BFD_RELOC_IP2K_EX8DATA:
217       return &ip2k_elf_howto_table[ (int) R_IP2K_EX8DATA];
218     default:
219       /* Pacify gcc -Wall.  */
220       return NULL;
221     }
222   return NULL;
223 }
224 
225 static reloc_howto_type *
ip2k_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * r_name)226 ip2k_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
227 {
228   unsigned int i;
229 
230   for (i = 0;
231        i < sizeof (ip2k_elf_howto_table) / sizeof (ip2k_elf_howto_table[0]);
232        i++)
233     if (ip2k_elf_howto_table[i].name != NULL
234 	&& strcasecmp (ip2k_elf_howto_table[i].name, r_name) == 0)
235       return &ip2k_elf_howto_table[i];
236 
237   return NULL;
238 }
239 
240 static void
ip2k_get_mem(bfd * abfd ATTRIBUTE_UNUSED,bfd_byte * addr,int length,bfd_byte * ptr)241 ip2k_get_mem (bfd *abfd ATTRIBUTE_UNUSED,
242 	      bfd_byte *addr,
243 	      int length,
244 	      bfd_byte *ptr)
245 {
246   while (length --)
247     * ptr ++ = bfd_get_8 (abfd, addr ++);
248 }
249 
250 static bool
ip2k_is_opcode(bfd_byte * code,const struct ip2k_opcode * opcodes)251 ip2k_is_opcode (bfd_byte *code, const struct ip2k_opcode *opcodes)
252 {
253   unsigned short insn = (code[0] << 8) | code[1];
254 
255   while (opcodes->mask != 0)
256     {
257       if ((insn & opcodes->mask) == opcodes->opcode)
258 	return true;
259 
260       opcodes ++;
261     }
262 
263   return false;
264 }
265 
266 #define PAGENO(ABSADDR) ((ABSADDR) & 0xFFFFC000)
267 #define BASEADDR(SEC)	((SEC)->output_section->vma + (SEC)->output_offset)
268 
269 #define UNDEFINED_SYMBOL (~(bfd_vma)0)
270 
271 /* Return the value of the symbol associated with the relocation IREL.  */
272 
273 static bfd_vma
symbol_value(bfd * abfd,Elf_Internal_Shdr * symtab_hdr,Elf_Internal_Sym * isymbuf,Elf_Internal_Rela * irel)274 symbol_value (bfd *abfd,
275 	      Elf_Internal_Shdr *symtab_hdr,
276 	      Elf_Internal_Sym *isymbuf,
277 	      Elf_Internal_Rela *irel)
278 {
279   if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
280     {
281       Elf_Internal_Sym *isym;
282       asection *sym_sec;
283 
284       isym = isymbuf + ELF32_R_SYM (irel->r_info);
285       if (isym->st_shndx == SHN_UNDEF)
286 	sym_sec = bfd_und_section_ptr;
287       else if (isym->st_shndx == SHN_ABS)
288 	sym_sec = bfd_abs_section_ptr;
289       else if (isym->st_shndx == SHN_COMMON)
290 	sym_sec = bfd_com_section_ptr;
291       else
292 	sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
293 
294       return isym->st_value + BASEADDR (sym_sec);
295     }
296   else
297     {
298       unsigned long indx;
299       struct elf_link_hash_entry *h;
300 
301       indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
302       h = elf_sym_hashes (abfd)[indx];
303       BFD_ASSERT (h != NULL);
304 
305       if (h->root.type != bfd_link_hash_defined
306 	  && h->root.type != bfd_link_hash_defweak)
307 	return UNDEFINED_SYMBOL;
308 
309       return (h->root.u.def.value + BASEADDR (h->root.u.def.section));
310     }
311 }
312 
313 /* Determine if the instruction sequence matches that for
314    the prologue of a switch dispatch table with fewer than
315    128 entries.
316 
317 	  sc
318 	  page	  $nnn0
319 	  jmp	  $nnn0
320 	  add	  w,wreg
321 	  add	  pcl,w
322   addr=>
323 	  page	  $nnn1
324 	  jmp	  $nnn1
325 	   page	   $nnn2
326 	   jmp	   $nnn2
327 	   ...
328 	   page	   $nnnN
329 	   jmp	   $nnnN
330 
331   After relaxation.
332 	   sc
333 	   page	   $nnn0
334 	   jmp	   $nnn0
335 	   add	   pcl,w
336   addr=>
337 	   jmp	   $nnn1
338 	   jmp	   $nnn2
339 	   ...
340 	  jmp	  $nnnN  */
341 
342 static int
ip2k_is_switch_table_128(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,bfd_vma addr,bfd_byte * contents)343 ip2k_is_switch_table_128 (bfd *abfd ATTRIBUTE_UNUSED,
344 			  asection *sec,
345 			  bfd_vma addr,
346 			  bfd_byte *contents)
347 {
348   bfd_byte code[4];
349   int table_index = 0;
350 
351   /* Check current page-jmp.  */
352   if (addr + 4 > sec->size)
353     return -1;
354 
355   ip2k_get_mem (abfd, contents + addr, 4, code);
356 
357   if ((! IS_PAGE_OPCODE (code + 0))
358       || (! IS_JMP_OPCODE (code + 2)))
359     return -1;
360 
361   /* Search back.  */
362   while (1)
363     {
364       if (addr < 4)
365 	return -1;
366 
367       /* Check previous 2 instructions.  */
368       ip2k_get_mem (abfd, contents + addr - 4, 4, code);
369       if ((IS_ADD_W_WREG_OPCODE (code + 0))
370 	  && (IS_ADD_PCL_W_OPCODE (code + 2)))
371 	return table_index;
372 
373       if ((! IS_PAGE_OPCODE (code + 0))
374 	  || (! IS_JMP_OPCODE (code + 2)))
375 	return -1;
376 
377       table_index++;
378       addr -= 4;
379     }
380 }
381 
382 /* Determine if the instruction sequence matches that for
383    the prologue switch dispatch table with fewer than
384    256 entries but more than 127.
385 
386    Before relaxation.
387 	  push	  %lo8insn(label) ; Push address of table
388 	  push	  %hi8insn(label)
389 	  add	  w,wreg	  ; index*2 => offset
390 	  snc			  ; CARRY SET?
391 	  inc	  1(sp)		  ; Propagate MSB into table address
392 	  add	  2(sp),w	  ; Add low bits of offset to table address
393 	  snc			  ; and handle any carry-out
394 	  inc	  1(sp)
395    addr=>
396 	  page	  __indjmp	  ; Do an indirect jump to that location
397 	  jmp	  __indjmp
398    label:			  ; case dispatch table starts here
399 	   page	   $nnn1
400 	   jmp	   $nnn1
401 	   page	   $nnn2
402 	   jmp	   $nnn2
403 	   ...
404 	   page	   $nnnN
405 	   jmp	   $nnnN
406 
407   After relaxation.
408 	  push	  %lo8insn(label) ; Push address of table
409 	  push	  %hi8insn(label)
410 	  add	  2(sp),w	  ; Add low bits of offset to table address
411 	  snc			  ; and handle any carry-out
412 	  inc	  1(sp)
413   addr=>
414 	  page	  __indjmp	  ; Do an indirect jump to that location
415 	  jmp	  __indjmp
416    label:			  ; case dispatch table starts here
417 	  jmp	  $nnn1
418 	  jmp	  $nnn2
419 	  ...
420 	  jmp	  $nnnN  */
421 
422 static int
ip2k_is_switch_table_256(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,bfd_vma addr,bfd_byte * contents)423 ip2k_is_switch_table_256 (bfd *abfd ATTRIBUTE_UNUSED,
424 			  asection *sec,
425 			  bfd_vma addr,
426 			  bfd_byte *contents)
427 {
428   bfd_byte code[16];
429   int table_index = 0;
430 
431   /* Check current page-jmp.  */
432   if (addr + 4 > sec->size)
433     return -1;
434 
435   ip2k_get_mem (abfd, contents + addr, 4, code);
436   if ((! IS_PAGE_OPCODE (code + 0))
437       || (! IS_JMP_OPCODE (code + 2)))
438     return -1;
439 
440   /* Search back.  */
441   while (1)
442     {
443       if (addr < 16)
444 	return -1;
445 
446       /* Check previous 8 instructions.  */
447       ip2k_get_mem (abfd, contents + addr - 16, 16, code);
448       if ((IS_ADD_W_WREG_OPCODE (code + 0))
449 	  && (IS_SNC_OPCODE (code + 2))
450 	  && (IS_INC_1SP_OPCODE (code + 4))
451 	  && (IS_ADD_2SP_W_OPCODE (code + 6))
452 	  && (IS_SNC_OPCODE (code + 8))
453 	  && (IS_INC_1SP_OPCODE (code + 10))
454 	  && (IS_PAGE_OPCODE (code + 12))
455 	  && (IS_JMP_OPCODE (code + 14)))
456 	return table_index;
457 
458       if ((IS_ADD_W_WREG_OPCODE (code + 2))
459 	  && (IS_SNC_OPCODE (code + 4))
460 	  && (IS_INC_1SP_OPCODE (code + 6))
461 	  && (IS_ADD_2SP_W_OPCODE (code + 8))
462 	  && (IS_SNC_OPCODE (code + 10))
463 	  && (IS_INC_1SP_OPCODE (code + 12))
464 	  && (IS_JMP_OPCODE (code + 14)))
465 	return table_index;
466 
467       if ((! IS_PAGE_OPCODE (code + 0))
468 	  || (! IS_JMP_OPCODE (code + 2)))
469 	return -1;
470 
471       table_index++;
472       addr -= 4;
473     }
474 }
475 
476 /* Returns the expected page state for the given instruction not including
477    the effect of page instructions.  */
478 
479 static bfd_vma
ip2k_nominal_page_bits(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,bfd_vma addr,bfd_byte * contents)480 ip2k_nominal_page_bits (bfd *abfd ATTRIBUTE_UNUSED,
481 			asection *sec,
482 			bfd_vma addr,
483 			bfd_byte *contents)
484 {
485   bfd_vma page = PAGENO (BASEADDR (sec) + addr);
486 
487   /* Check if section flows into this page. If not then the page
488      bits are assumed to match the PC. This will be true unless
489      the user has a page instruction without a call/jump, in which
490      case they are on their own.  */
491   if (PAGENO (BASEADDR (sec)) == page)
492     return page;
493 
494   /* Section flows across page boundary. The page bits should match
495      the PC unless there is a possible flow from the previous page,
496      in which case it is not possible to determine the value of the
497      page bits.  */
498   while (PAGENO (BASEADDR (sec) + addr - 2) == page)
499     {
500       bfd_byte code[2];
501 
502       addr -= 2;
503       ip2k_get_mem (abfd, contents + addr, 2, code);
504       if (!IS_PAGE_OPCODE (code))
505 	continue;
506 
507       /* Found a page instruction, check if jump table.  */
508       if (ip2k_is_switch_table_128 (abfd, sec, addr, contents) != -1)
509 	/* Jump table => page is conditional.  */
510 	continue;
511 
512       if (ip2k_is_switch_table_256 (abfd, sec, addr, contents) != -1)
513 	/* Jump table => page is conditional.  */
514 	continue;
515 
516       /* Found a page instruction, check if conditional.  */
517       if (addr >= 2)
518 	{
519 	  ip2k_get_mem (abfd, contents + addr - 2, 2, code);
520 	  if (IS_SKIP_OPCODE (code))
521 	    /* Page is conditional.  */
522 	    continue;
523 	}
524 
525       /* Unconditional page instruction => page bits should be correct.  */
526       return page;
527     }
528 
529   /* Flow from previous page => page bits are impossible to determine.  */
530   return 0;
531 }
532 
533 static bool
ip2k_test_page_insn(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,Elf_Internal_Rela * irel,struct misc * misc)534 ip2k_test_page_insn (bfd *abfd ATTRIBUTE_UNUSED,
535 		     asection *sec,
536 		     Elf_Internal_Rela *irel,
537 		     struct misc *misc)
538 {
539   bfd_vma symval;
540 
541   /* Get the value of the symbol referred to by the reloc.  */
542   symval = symbol_value (abfd, misc->symtab_hdr, misc->isymbuf, irel);
543   if (symval == UNDEFINED_SYMBOL)
544     /* This appears to be a reference to an undefined
545        symbol.  Just ignore it--it will be caught by the
546        regular reloc processing.  */
547     return false;
548 
549   /* Test if we can delete this page instruction.  */
550   if (PAGENO (symval + irel->r_addend) !=
551       ip2k_nominal_page_bits (abfd, sec, irel->r_offset, misc->contents))
552     return false;
553 
554   return true;
555 }
556 
557 /* Parts of a Stabs entry.  */
558 
559 #define STRDXOFF   0
560 #define TYPEOFF    4
561 #define OTHEROFF   5
562 #define DESCOFF    6
563 #define VALOFF     8
564 #define STABSIZE   12
565 
566 /* Adjust all the relocations entries after adding or inserting instructions.  */
567 
568 static void
adjust_all_relocations(bfd * abfd,asection * sec,bfd_vma addr,bfd_vma endaddr,int count,int noadj)569 adjust_all_relocations (bfd *abfd,
570 			asection *sec,
571 			bfd_vma addr,
572 			bfd_vma endaddr,
573 			int count,
574 			int noadj)
575 {
576   Elf_Internal_Shdr *symtab_hdr;
577   Elf_Internal_Sym *isymbuf, *isym, *isymend;
578   unsigned int shndx;
579   Elf_Internal_Rela *irel, *irelend, *irelbase;
580   struct elf_link_hash_entry **sym_hashes;
581   struct elf_link_hash_entry **end_hashes;
582   unsigned int symcount;
583   asection *stab;
584 
585   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
586   isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
587 
588   shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
589 
590   irelbase = elf_section_data (sec)->relocs;
591   irelend = irelbase + sec->reloc_count;
592 
593   for (irel = irelbase; irel < irelend; irel++)
594     {
595       if (ELF32_R_TYPE (irel->r_info) != R_IP2K_NONE)
596 	{
597 	  /* Get the value of the symbol referred to by the reloc.  */
598 	  if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
599 	    {
600 	      asection *sym_sec;
601 
602 	      /* A local symbol.  */
603 	      isym = isymbuf + ELF32_R_SYM (irel->r_info);
604 	      sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
605 
606 	      if (isym->st_shndx == shndx)
607 		{
608 		  bfd_vma baseaddr = BASEADDR (sec);
609 		  bfd_vma symval = BASEADDR (sym_sec) + isym->st_value
610 				   + irel->r_addend;
611 
612 		  if ((baseaddr + addr + noadj) <= symval
613 		      && symval < (baseaddr + endaddr))
614 		    irel->r_addend += count;
615 		}
616 	    }
617 	}
618 
619       /* Do this only for PC space relocations.  */
620       if (addr <= irel->r_offset && irel->r_offset < endaddr)
621 	irel->r_offset += count;
622     }
623 
624   /* Now fix the stab relocations.  */
625   stab = bfd_get_section_by_name (abfd, ".stab");
626   if (stab)
627     {
628       bfd_byte *stabcontents, *stabend, *stabp;
629       bfd_size_type stab_size = stab->rawsize ? stab->rawsize : stab->size;
630 
631       irelbase = elf_section_data (stab)->relocs;
632       irelend = irelbase + stab->reloc_count;
633 
634       /* Pull out the contents of the stab section.  */
635       if (elf_section_data (stab)->this_hdr.contents != NULL)
636 	stabcontents = elf_section_data (stab)->this_hdr.contents;
637       else
638 	{
639 	  if (!bfd_malloc_and_get_section (abfd, stab, &stabcontents))
640 	    {
641 	      free (stabcontents);
642 	      return;
643 	    }
644 
645 	  /* We need to remember this.  */
646 	  elf_section_data (stab)->this_hdr.contents = stabcontents;
647 	}
648 
649       stabend = stabcontents + stab_size;
650 
651       for (irel = irelbase; irel < irelend; irel++)
652 	{
653 	  if (ELF32_R_TYPE (irel->r_info) != R_IP2K_NONE)
654 	    {
655 	      /* Get the value of the symbol referred to by the reloc.  */
656 	      if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
657 		{
658 		  asection *sym_sec;
659 
660 		  /* A local symbol.  */
661 		  isym = isymbuf + ELF32_R_SYM (irel->r_info);
662 		  sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
663 
664 		  if (sym_sec == sec)
665 		    {
666 		      const char *name;
667 		      unsigned char type;
668 		      bfd_vma value;
669 		      bfd_vma baseaddr = BASEADDR (sec);
670 		      bfd_vma symval = BASEADDR (sym_sec) + isym->st_value
671 			+ irel->r_addend;
672 
673 		      if ((baseaddr + addr) <= symval
674 			  && symval <= (baseaddr + endaddr))
675 			irel->r_addend += count;
676 
677 		      /* Go hunt up a function and fix its line info if needed.  */
678 		      stabp = stabcontents + irel->r_offset - 8;
679 
680 		      /* Go pullout the stab entry.  */
681 		      type  = bfd_h_get_8 (abfd, stabp + TYPEOFF);
682 		      value = bfd_h_get_32 (abfd, stabp + VALOFF);
683 
684 		      name = bfd_get_stab_name (type);
685 
686 		      if (strcmp (name, "FUN") == 0)
687 			{
688 			  int function_adjusted = 0;
689 
690 			  if (symval > (baseaddr + addr))
691 			    /* Not in this function.  */
692 			    continue;
693 
694 			  /* Hey we got a function hit.  */
695 			  stabp += STABSIZE;
696 			  for (;stabp < stabend; stabp += STABSIZE)
697 			    {
698 			      /* Go pullout the stab entry.  */
699 			      type  = bfd_h_get_8 (abfd, stabp + TYPEOFF);
700 			      value = bfd_h_get_32 (abfd, stabp + VALOFF);
701 
702 			      name = bfd_get_stab_name (type);
703 
704 			      if (strcmp (name, "FUN") == 0)
705 				{
706 				  /* Hit another function entry.  */
707 				  if (function_adjusted)
708 				    {
709 				      /* Adjust the value.  */
710 				      value += count;
711 
712 				      /* We need to put it back.  */
713 				      bfd_h_put_32 (abfd, value,stabp + VALOFF);
714 				    }
715 
716 				  /* And then bale out.  */
717 				  break;
718 				}
719 
720 			      if (strcmp (name, "SLINE") == 0)
721 				{
722 				  /* Got a line entry.  */
723 				  if ((baseaddr + addr) <= (symval + value))
724 				    {
725 				      /* Adjust the line entry.  */
726 				      value += count;
727 
728 				      /* We need to put it back.  */
729 				      bfd_h_put_32 (abfd, value,stabp + VALOFF);
730 				      function_adjusted = 1;
731 				    }
732 				}
733 			    }
734 			}
735 		    }
736 		}
737 	    }
738 	}
739     }
740 
741   /* When adding an instruction back it is sometimes necessary to move any
742      global or local symbol that was referencing the first instruction of
743      the moved block to refer to the first instruction of the inserted block.
744 
745      For example adding a PAGE instruction before a CALL or JMP requires
746      that any label on the CALL or JMP is moved to the PAGE insn.  */
747   addr += noadj;
748 
749   /* Adjust the local symbols defined in this section.  */
750   isymend = isymbuf + symtab_hdr->sh_info;
751   for (isym = isymbuf; isym < isymend; isym++)
752     {
753       if (isym->st_shndx == shndx
754 	  && addr <= isym->st_value
755 	  && isym->st_value < endaddr)
756 	isym->st_value += count;
757     }
758 
759   /* Now adjust the global symbols defined in this section.  */
760   symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
761 	      - symtab_hdr->sh_info);
762   sym_hashes = elf_sym_hashes (abfd);
763   end_hashes = sym_hashes + symcount;
764   for (; sym_hashes < end_hashes; sym_hashes++)
765     {
766       struct elf_link_hash_entry *sym_hash = *sym_hashes;
767 
768       if ((sym_hash->root.type == bfd_link_hash_defined
769 	   || sym_hash->root.type == bfd_link_hash_defweak)
770 	  && sym_hash->root.u.def.section == sec)
771 	{
772 	  if (addr <= sym_hash->root.u.def.value
773 	      && sym_hash->root.u.def.value < endaddr)
774 	    sym_hash->root.u.def.value += count;
775 	}
776     }
777 
778   return;
779 }
780 
781 /* Delete some bytes from a section while relaxing.  */
782 
783 static bool
ip2k_elf_relax_delete_bytes(bfd * abfd,asection * sec,bfd_vma addr,int count)784 ip2k_elf_relax_delete_bytes (bfd *abfd,
785 			     asection *sec,
786 			     bfd_vma addr,
787 			     int count)
788 {
789   bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
790   bfd_vma endaddr = sec->size;
791 
792   /* Actually delete the bytes.  */
793   memmove (contents + addr, contents + addr + count,
794 	   endaddr - addr - count);
795 
796   sec->size -= count;
797 
798   adjust_all_relocations (abfd, sec, addr + count, endaddr, -count, 0);
799   return true;
800 }
801 
802 static bool
ip2k_delete_page_insn(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,Elf_Internal_Rela * irel,bool * again,struct misc * misc)803 ip2k_delete_page_insn (bfd *abfd ATTRIBUTE_UNUSED,
804 		       asection *sec,
805 		       Elf_Internal_Rela *irel,
806 		       bool *again,
807 		       struct misc *misc)
808 {
809   /* Note that we've changed the relocs, section contents, etc.  */
810   elf_section_data (sec)->relocs = misc->irelbase;
811   elf_section_data (sec)->this_hdr.contents = misc->contents;
812   misc->symtab_hdr->contents = (bfd_byte *) misc->isymbuf;
813 
814   /* Fix the relocation's type.  */
815   irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info), R_IP2K_NONE);
816 
817   /* Delete the PAGE insn.  */
818   if (!ip2k_elf_relax_delete_bytes (abfd, sec, irel->r_offset, 2))
819     return false;
820 
821   /* Modified => will need to iterate relaxation again.  */
822   *again = true;
823 
824   return true;
825 }
826 
827 static bool
ip2k_relax_switch_table_128(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,Elf_Internal_Rela * irel,bool * again,struct misc * misc)828 ip2k_relax_switch_table_128 (bfd *abfd ATTRIBUTE_UNUSED,
829 			     asection *sec,
830 			     Elf_Internal_Rela *irel,
831 			     bool *again,
832 			     struct misc *misc)
833 {
834   Elf_Internal_Rela *irelend = misc->irelbase + sec->reloc_count;
835   Elf_Internal_Rela *ireltest = irel;
836   bfd_byte code[4];
837   bfd_vma addr;
838 
839   /* Test all page instructions.  */
840   addr = irel->r_offset;
841   while (1)
842     {
843       if (addr + 4 > sec->size)
844 	break;
845 
846       ip2k_get_mem (abfd, misc->contents + addr, 4, code);
847       if ((! IS_PAGE_OPCODE (code + 0))
848 	  || (! IS_JMP_OPCODE (code + 2)))
849 	break;
850 
851       /* Validate relocation entry (every entry should have a matching
852 	  relocation entry).  */
853       if (ireltest >= irelend)
854 	{
855 	  _bfd_error_handler (_("ip2k relaxer: switch table without complete matching relocation information."));
856 	  return false;
857 	}
858 
859       if (ireltest->r_offset != addr)
860 	{
861 	  _bfd_error_handler (_("ip2k relaxer: switch table without complete matching relocation information."));
862 	  return false;
863 	}
864 
865       if (! ip2k_test_page_insn (abfd, sec, ireltest, misc))
866 	/* Un-removable page insn => nothing can be done.  */
867 	return true;
868 
869       addr += 4;
870       ireltest += 2;
871     }
872 
873   /* Relaxable. Adjust table header.  */
874   ip2k_get_mem (abfd, misc->contents + irel->r_offset - 4, 4, code);
875   if ((! IS_ADD_W_WREG_OPCODE (code + 0))
876       || (! IS_ADD_PCL_W_OPCODE (code + 2)))
877     {
878       _bfd_error_handler (_("ip2k relaxer: switch table header corrupt."));
879       return false;
880     }
881 
882   if (!ip2k_elf_relax_delete_bytes (abfd, sec, irel->r_offset - 4, 2))
883     return false;
884 
885   *again = true;
886 
887   /* Delete all page instructions in table.  */
888   while (irel < ireltest)
889     {
890       if (!ip2k_delete_page_insn (abfd, sec, irel, again, misc))
891 	return false;
892       irel += 2;
893     }
894 
895   return true;
896 }
897 
898 static bool
ip2k_relax_switch_table_256(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,Elf_Internal_Rela * irel,bool * again,struct misc * misc)899 ip2k_relax_switch_table_256 (bfd *abfd ATTRIBUTE_UNUSED,
900 			     asection *sec,
901 			     Elf_Internal_Rela *irel,
902 			     bool *again,
903 			     struct misc *misc)
904 {
905   Elf_Internal_Rela *irelend = misc->irelbase + sec->reloc_count;
906   Elf_Internal_Rela *ireltest = irel;
907   bfd_byte code[12];
908   bfd_vma addr;
909 
910   /* Test all page instructions.  */
911   addr = irel->r_offset;
912 
913   while (1)
914     {
915       if (addr + 4 > sec->size)
916 	break;
917 
918       ip2k_get_mem (abfd, misc->contents + addr, 4, code);
919 
920       if ((! IS_PAGE_OPCODE (code + 0))
921 	  || (! IS_JMP_OPCODE (code + 2)))
922 	break;
923 
924       /* Validate relocation entry (every entry should have a matching
925 	  relocation entry).  */
926       if (ireltest >= irelend)
927 	{
928 	  _bfd_error_handler (_("ip2k relaxer: switch table without complete matching relocation information."));
929 	  return false;
930 	}
931 
932       if (ireltest->r_offset != addr)
933 	{
934 	  _bfd_error_handler (_("ip2k relaxer: switch table without complete matching relocation information."));
935 	  return false;
936 	}
937 
938       if (!ip2k_test_page_insn (abfd, sec, ireltest, misc))
939 	/* Un-removable page insn => nothing can be done.  */
940 	return true;
941 
942       addr += 4;
943       ireltest += 2;
944     }
945 
946   /* Relaxable. Adjust table header.  */
947   ip2k_get_mem (abfd, misc->contents + irel->r_offset - 4, 2, code);
948   if (IS_PAGE_OPCODE (code))
949     addr = irel->r_offset - 16;
950   else
951     addr = irel->r_offset - 14;
952 
953   ip2k_get_mem (abfd, misc->contents + addr, 12, code);
954   if ((!IS_ADD_W_WREG_OPCODE (code + 0))
955       || (!IS_SNC_OPCODE (code + 2))
956       || (!IS_INC_1SP_OPCODE (code + 4))
957       || (!IS_ADD_2SP_W_OPCODE (code + 6))
958       || (!IS_SNC_OPCODE (code + 8))
959       || (!IS_INC_1SP_OPCODE (code + 10)))
960     {
961       _bfd_error_handler (_("ip2k relaxer: switch table header corrupt."));
962       return false;
963     }
964 
965   /* Delete first 3 opcodes.  */
966   if (!ip2k_elf_relax_delete_bytes (abfd, sec, addr + 0, 6))
967     return false;
968 
969   *again = true;
970 
971   /* Delete all page instructions in table.  */
972   while (irel < ireltest)
973     {
974       if (!ip2k_delete_page_insn (abfd, sec, irel, again, misc))
975 	return false;
976       irel += 2;
977     }
978 
979   return true;
980 }
981 
982 /* This function handles relaxation of a section in a specific page.  */
983 
984 static bool
ip2k_elf_relax_section_page(bfd * abfd,asection * sec,bool * again,struct misc * misc,unsigned long page_start,unsigned long page_end)985 ip2k_elf_relax_section_page (bfd *abfd,
986 			     asection *sec,
987 			     bool *again,
988 			     struct misc *misc,
989 			     unsigned long page_start,
990 			     unsigned long page_end)
991 {
992   Elf_Internal_Rela *irelend = misc->irelbase + sec->reloc_count;
993   Elf_Internal_Rela *irel;
994   int switch_table_128;
995   int switch_table_256;
996 
997   /* Walk thru the section looking for relaxation opportunities.  */
998   for (irel = misc->irelbase; irel < irelend; irel++)
999     {
1000       if (ELF32_R_TYPE (irel->r_info) != (int) R_IP2K_PAGE3)
1001 	/* Ignore non page instructions.  */
1002 	continue;
1003 
1004       if (BASEADDR (sec) + irel->r_offset < page_start)
1005 	/* Ignore page instructions on earlier page - they have
1006 	   already been processed. Remember that there is code flow
1007 	   that crosses a page boundary.  */
1008 	continue;
1009 
1010       if (BASEADDR (sec) + irel->r_offset > page_end)
1011 	/* Flow beyond end of page => nothing more to do for this page.  */
1012 	return true;
1013 
1014       /* Detect switch tables.  */
1015       switch_table_128 = ip2k_is_switch_table_128 (abfd, sec, irel->r_offset, misc->contents);
1016       switch_table_256 = ip2k_is_switch_table_256 (abfd, sec, irel->r_offset, misc->contents);
1017 
1018       if ((switch_table_128 > 0) || (switch_table_256 > 0))
1019 	/* If the index is greater than 0 then it has already been processed.  */
1020 	continue;
1021 
1022       if (switch_table_128 == 0)
1023 	{
1024 	  if (!ip2k_relax_switch_table_128 (abfd, sec, irel, again, misc))
1025 	    return false;
1026 
1027 	  continue;
1028 	}
1029 
1030       if (switch_table_256 == 0)
1031 	{
1032 	  if (!ip2k_relax_switch_table_256 (abfd, sec, irel, again, misc))
1033 	    return false;
1034 
1035 	  continue;
1036 	}
1037 
1038       /* Simple relax.  */
1039       if (ip2k_test_page_insn (abfd, sec, irel, misc))
1040 	{
1041 	  if (!ip2k_delete_page_insn (abfd, sec, irel, again, misc))
1042 	    return false;
1043 
1044 	  continue;
1045 	}
1046     }
1047 
1048   return true;
1049 }
1050 
1051 /* This function handles relaxing for the ip2k.
1052 
1053    Principle: Start with the first page and remove page instructions that
1054    are not require on this first page. By removing page instructions more
1055    code will fit into this page - repeat until nothing more can be achieved
1056    for this page. Move on to the next page.
1057 
1058    Processing the pages one at a time from the lowest page allows a removal
1059    only policy to be used - pages can be removed but are never reinserted.  */
1060 
1061 static bool
ip2k_elf_relax_section(bfd * abfd,asection * sec,struct bfd_link_info * link_info,bool * again)1062 ip2k_elf_relax_section (bfd *abfd,
1063 			asection *sec,
1064 			struct bfd_link_info *link_info,
1065 			bool *again)
1066 {
1067   Elf_Internal_Shdr *symtab_hdr;
1068   Elf_Internal_Rela *internal_relocs;
1069   bfd_byte *contents = NULL;
1070   Elf_Internal_Sym *isymbuf = NULL;
1071   static asection * first_section = NULL;
1072   static unsigned long search_addr;
1073   static unsigned long page_start = 0;
1074   static unsigned long page_end = 0;
1075   static unsigned int pass = 0;
1076   static bool new_pass = false;
1077   static bool changed = false;
1078   struct misc misc;
1079 
1080   /* Assume nothing changes.  */
1081   *again = false;
1082 
1083   if (first_section == NULL)
1084     {
1085       ip2k_relaxed = true;
1086       first_section = sec;
1087     }
1088 
1089   if (first_section == sec)
1090     {
1091       pass++;
1092       new_pass = true;
1093     }
1094 
1095   /* We don't have to do anything for a relocatable link,
1096      if this section does not have relocs, or if this is
1097      not a code section.  */
1098   if (bfd_link_relocatable (link_info)
1099       || (sec->flags & SEC_RELOC) == 0
1100       || sec->reloc_count == 0
1101       || (sec->flags & SEC_CODE) == 0)
1102     return true;
1103 
1104   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1105 
1106   internal_relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
1107 					       link_info->keep_memory);
1108   if (internal_relocs == NULL)
1109     goto error_return;
1110 
1111   /* Get section contents cached copy if it exists.  */
1112   if (contents == NULL)
1113     {
1114       /* Get cached copy if it exists.  */
1115       if (elf_section_data (sec)->this_hdr.contents != NULL)
1116 	contents = elf_section_data (sec)->this_hdr.contents;
1117       else
1118 	{
1119 	  /* Go get them off disk.  */
1120 	  if (!bfd_malloc_and_get_section (abfd, sec, &contents))
1121 	    goto error_return;
1122 	}
1123     }
1124 
1125   /* Read this BFD's symbols cached copy if it exists.  */
1126   if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1127     {
1128       isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1129       if (isymbuf == NULL)
1130 	isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1131 					symtab_hdr->sh_info, 0,
1132 					NULL, NULL, NULL);
1133       if (isymbuf == NULL)
1134 	goto error_return;
1135     }
1136 
1137   misc.symtab_hdr = symtab_hdr;
1138   misc.isymbuf = isymbuf;
1139   misc.irelbase = internal_relocs;
1140   misc.contents = contents;
1141 
1142   /* This is where all the relaxation actually get done.  */
1143   if ((pass == 1) || (new_pass && !changed))
1144     {
1145       /* On the first pass we simply search for the lowest page that
1146 	 we havn't relaxed yet. Note that the pass count is reset
1147 	 each time a page is complete in order to move on to the next page.
1148 	 If we can't find any more pages then we are finished.  */
1149       if (new_pass)
1150 	{
1151 	  pass = 1;
1152 	  new_pass = false;
1153 	  changed = true; /* Pre-initialize to break out of pass 1.  */
1154 	  search_addr = 0xFFFFFFFF;
1155 	}
1156 
1157       if ((BASEADDR (sec) + sec->size < search_addr)
1158 	  && (BASEADDR (sec) + sec->size > page_end))
1159 	{
1160 	  if (BASEADDR (sec) <= page_end)
1161 	    search_addr = page_end + 1;
1162 	  else
1163 	    search_addr = BASEADDR (sec);
1164 
1165 	  /* Found a page => more work to do.  */
1166 	  *again = true;
1167 	}
1168     }
1169   else
1170     {
1171       if (new_pass)
1172 	{
1173 	  new_pass = false;
1174 	  changed = false;
1175 	  page_start = PAGENO (search_addr);
1176 	  page_end = page_start | 0x00003FFF;
1177 	}
1178 
1179       /* Only process sections in range.  */
1180       if ((BASEADDR (sec) + sec->size >= page_start)
1181 	  && (BASEADDR (sec) <= page_end))
1182 	{
1183 	  if (!ip2k_elf_relax_section_page (abfd, sec, &changed, &misc, page_start, page_end))
1184 	    return false;
1185 	}
1186       *again = true;
1187     }
1188 
1189   /* Perform some house keeping after relaxing the section.  */
1190 
1191   if (isymbuf != NULL
1192       && symtab_hdr->contents != (unsigned char *) isymbuf)
1193     {
1194       if (! link_info->keep_memory)
1195 	free (isymbuf);
1196       else
1197 	symtab_hdr->contents = (unsigned char *) isymbuf;
1198     }
1199 
1200   if (contents != NULL
1201       && elf_section_data (sec)->this_hdr.contents != contents)
1202     {
1203       if (! link_info->keep_memory)
1204 	free (contents);
1205       else
1206 	{
1207 	  /* Cache the section contents for elf_link_input_bfd.  */
1208 	  elf_section_data (sec)->this_hdr.contents = contents;
1209 	}
1210     }
1211 
1212   if (elf_section_data (sec)->relocs != internal_relocs)
1213     free (internal_relocs);
1214 
1215   return true;
1216 
1217  error_return:
1218   if (symtab_hdr->contents != (unsigned char *) isymbuf)
1219     free (isymbuf);
1220   if (elf_section_data (sec)->this_hdr.contents != contents)
1221     free (contents);
1222   if (elf_section_data (sec)->relocs != internal_relocs)
1223     free (internal_relocs);
1224   return false;
1225 }
1226 
1227 /* Set the howto pointer for a IP2K ELF reloc.  */
1228 
1229 static bool
ip2k_info_to_howto_rela(bfd * abfd,arelent * cache_ptr,Elf_Internal_Rela * dst)1230 ip2k_info_to_howto_rela (bfd * abfd,
1231 			 arelent * cache_ptr,
1232 			 Elf_Internal_Rela * dst)
1233 {
1234   unsigned int r_type;
1235 
1236   r_type = ELF32_R_TYPE (dst->r_info);
1237   if (r_type >= (unsigned int) R_IP2K_max)
1238     {
1239       /* xgettext:c-format */
1240       _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
1241 			  abfd, r_type);
1242       bfd_set_error (bfd_error_bad_value);
1243       return false;
1244     }
1245   cache_ptr->howto = & ip2k_elf_howto_table [r_type];
1246   return true;
1247 }
1248 
1249 /* Perform a single relocation.
1250    By default we use the standard BFD routines.  */
1251 
1252 static bfd_reloc_status_type
ip2k_final_link_relocate(reloc_howto_type * howto,bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * rel,bfd_vma relocation)1253 ip2k_final_link_relocate (reloc_howto_type *  howto,
1254 			  bfd *		      input_bfd,
1255 			  asection *	      input_section,
1256 			  bfd_byte *	      contents,
1257 			  Elf_Internal_Rela * rel,
1258 			  bfd_vma	      relocation)
1259 {
1260   static bfd_vma page_addr = 0;
1261 
1262   bfd_reloc_status_type r = bfd_reloc_ok;
1263   switch (howto->type)
1264     {
1265       /* Handle data space relocations.  */
1266     case R_IP2K_FR9:
1267     case R_IP2K_BANK:
1268       if ((relocation & IP2K_DATA_MASK) == IP2K_DATA_VALUE)
1269 	relocation &= ~IP2K_DATA_MASK;
1270       else
1271 	r = bfd_reloc_notsupported;
1272       break;
1273 
1274     case R_IP2K_LO8DATA:
1275     case R_IP2K_HI8DATA:
1276     case R_IP2K_EX8DATA:
1277       break;
1278 
1279       /* Handle insn space relocations.  */
1280     case R_IP2K_PAGE3:
1281       page_addr = BASEADDR (input_section) + rel->r_offset;
1282       if ((relocation & IP2K_INSN_MASK) == IP2K_INSN_VALUE)
1283 	relocation &= ~IP2K_INSN_MASK;
1284       else
1285 	r = bfd_reloc_notsupported;
1286       break;
1287 
1288     case R_IP2K_ADDR16CJP:
1289       if (BASEADDR (input_section) + rel->r_offset != page_addr + 2)
1290 	{
1291 	  /* No preceding page instruction, verify that it isn't needed.  */
1292 	  if (PAGENO (relocation + rel->r_addend) !=
1293 	      ip2k_nominal_page_bits (input_bfd, input_section,
1294 				      rel->r_offset, contents))
1295 	    /* xgettext:c-format */
1296 	    _bfd_error_handler
1297 	      (_("ip2k linker: missing page instruction "
1298 		 "at %#" PRIx64 " (dest = %#" PRIx64 ")"),
1299 	       (uint64_t) (BASEADDR (input_section) + rel->r_offset),
1300 	       (uint64_t) (relocation + rel->r_addend));
1301 	}
1302       else if (ip2k_relaxed)
1303 	{
1304 	  /* Preceding page instruction. Verify that the page instruction is
1305 	     really needed. One reason for the relaxation to miss a page is if
1306 	     the section is not marked as executable.  */
1307 	  if (!ip2k_is_switch_table_128 (input_bfd, input_section,
1308 					 rel->r_offset - 2, contents)
1309 	      && !ip2k_is_switch_table_256 (input_bfd, input_section,
1310 					    rel->r_offset - 2, contents)
1311 	      && (PAGENO (relocation + rel->r_addend) ==
1312 		  ip2k_nominal_page_bits (input_bfd, input_section,
1313 					  rel->r_offset - 2, contents)))
1314 	    /* xgettext:c-format */
1315 	    _bfd_error_handler
1316 	      (_("ip2k linker: redundant page instruction "
1317 		 "at %#" PRIx64 " (dest = %#" PRIx64 ")"),
1318 	       (uint64_t) page_addr,
1319 	       (uint64_t) (relocation + rel->r_addend));
1320 	}
1321       if ((relocation & IP2K_INSN_MASK) == IP2K_INSN_VALUE)
1322 	relocation &= ~IP2K_INSN_MASK;
1323       else
1324 	r = bfd_reloc_notsupported;
1325       break;
1326 
1327     case R_IP2K_LO8INSN:
1328     case R_IP2K_HI8INSN:
1329     case R_IP2K_PC_SKIP:
1330       if ((relocation & IP2K_INSN_MASK) == IP2K_INSN_VALUE)
1331 	relocation &= ~IP2K_INSN_MASK;
1332       else
1333 	r = bfd_reloc_notsupported;
1334       break;
1335 
1336     case R_IP2K_16:
1337       /* If this is a relocation involving a TEXT
1338 	 symbol, reduce it to a word address.  */
1339       if ((relocation & IP2K_INSN_MASK) == IP2K_INSN_VALUE)
1340 	howto = &ip2k_elf_howto_table[ (int) R_IP2K_TEXT];
1341       break;
1342 
1343       /* Pass others through.  */
1344     default:
1345       break;
1346     }
1347 
1348   /* Only install relocation if above tests did not disqualify it.  */
1349   if (r == bfd_reloc_ok)
1350     r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1351 				  contents, rel->r_offset,
1352 				  relocation, rel->r_addend);
1353 
1354   return r;
1355 }
1356 
1357 /* Relocate a IP2K ELF section.
1358 
1359    The RELOCATE_SECTION function is called by the new ELF backend linker
1360    to handle the relocations for a section.
1361 
1362    The relocs are always passed as Rela structures; if the section
1363    actually uses Rel structures, the r_addend field will always be
1364    zero.
1365 
1366    This function is responsible for adjusting the section contents as
1367    necessary, and (if using Rela relocs and generating a relocatable
1368    output file) adjusting the reloc addend as necessary.
1369 
1370    This function does not have to worry about setting the reloc
1371    address or the reloc symbol index.
1372 
1373    LOCAL_SYMS is a pointer to the swapped in local symbols.
1374 
1375    LOCAL_SECTIONS is an array giving the section in the input file
1376    corresponding to the st_shndx field of each local symbol.
1377 
1378    The global hash table entry for the global symbols can be found
1379    via elf_sym_hashes (input_bfd).
1380 
1381    When generating relocatable output, this function must handle
1382    STB_LOCAL/STT_SECTION symbols specially.  The output symbol is
1383    going to be the section symbol corresponding to the output
1384    section, which means that the addend must be adjusted
1385    accordingly.  */
1386 
1387 static int
ip2k_elf_relocate_section(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * relocs,Elf_Internal_Sym * local_syms,asection ** local_sections)1388 ip2k_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
1389 			   struct bfd_link_info *info,
1390 			   bfd *input_bfd,
1391 			   asection *input_section,
1392 			   bfd_byte *contents,
1393 			   Elf_Internal_Rela *relocs,
1394 			   Elf_Internal_Sym *local_syms,
1395 			   asection **local_sections)
1396 {
1397   Elf_Internal_Shdr *symtab_hdr;
1398   struct elf_link_hash_entry **sym_hashes;
1399   Elf_Internal_Rela *rel;
1400   Elf_Internal_Rela *relend;
1401 
1402   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1403   sym_hashes = elf_sym_hashes (input_bfd);
1404   relend     = relocs + input_section->reloc_count;
1405 
1406   for (rel = relocs; rel < relend; rel ++)
1407     {
1408       reloc_howto_type *	   howto;
1409       unsigned long		   r_symndx;
1410       Elf_Internal_Sym *	   sym;
1411       asection *		   sec;
1412       struct elf_link_hash_entry * h;
1413       bfd_vma			   relocation;
1414       bfd_reloc_status_type	   r;
1415       const char *		   name = NULL;
1416       int			   r_type;
1417 
1418       r_type = ELF32_R_TYPE (rel->r_info);
1419       r_symndx = ELF32_R_SYM (rel->r_info);
1420       howto  = ip2k_elf_howto_table + r_type;
1421       h      = NULL;
1422       sym    = NULL;
1423       sec    = NULL;
1424 
1425       if (r_symndx < symtab_hdr->sh_info)
1426 	{
1427 	  sym = local_syms + r_symndx;
1428 	  sec = local_sections [r_symndx];
1429 	  relocation = BASEADDR (sec) + sym->st_value;
1430 
1431 	  name = bfd_elf_string_from_elf_section
1432 	    (input_bfd, symtab_hdr->sh_link, sym->st_name);
1433 	  name = name == NULL ? bfd_section_name (sec) : name;
1434 	}
1435       else
1436 	{
1437 	  bool warned, ignored;
1438 	  bool unresolved_reloc;
1439 
1440 	  RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1441 				   r_symndx, symtab_hdr, sym_hashes,
1442 				   h, sec, relocation,
1443 				   unresolved_reloc, warned, ignored);
1444 
1445 	  name = h->root.root.string;
1446 	}
1447 
1448       if (sec != NULL && discarded_section (sec))
1449 	RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
1450 					 rel, 1, relend, howto, 0, contents);
1451 
1452       if (bfd_link_relocatable (info))
1453 	continue;
1454 
1455       /* Finally, the sole IP2K-specific part.  */
1456       r = ip2k_final_link_relocate (howto, input_bfd, input_section,
1457 				     contents, rel, relocation);
1458 
1459       if (r != bfd_reloc_ok)
1460 	{
1461 	  const char * msg = NULL;
1462 
1463 	  switch (r)
1464 	    {
1465 	    case bfd_reloc_overflow:
1466 	      (*info->callbacks->reloc_overflow)
1467 		(info, (h ? &h->root : NULL), name, howto->name,
1468 		 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
1469 	      break;
1470 
1471 	    case bfd_reloc_undefined:
1472 	      (*info->callbacks->undefined_symbol)
1473 		(info, name, input_bfd, input_section, rel->r_offset, true);
1474 	      break;
1475 
1476 	    case bfd_reloc_outofrange:
1477 	      msg = _("internal error: out of range error");
1478 	      break;
1479 
1480 	      /* This is how ip2k_final_link_relocate tells us of a non-kosher
1481 		 reference between insn & data address spaces.  */
1482 	    case bfd_reloc_notsupported:
1483 	      if (sym != NULL) /* Only if it's not an unresolved symbol.  */
1484 		 msg = _("unsupported relocation between data/insn address spaces");
1485 	      break;
1486 
1487 	    case bfd_reloc_dangerous:
1488 	      msg = _("internal error: dangerous relocation");
1489 	      break;
1490 
1491 	    default:
1492 	      msg = _("internal error: unknown error");
1493 	      break;
1494 	    }
1495 
1496 	  if (msg)
1497 	    (*info->callbacks->warning) (info, msg, name, input_bfd,
1498 					 input_section, rel->r_offset);
1499 	}
1500     }
1501 
1502   return true;
1503 }
1504 
1505 #define TARGET_BIG_SYM	 ip2k_elf32_vec
1506 #define TARGET_BIG_NAME  "elf32-ip2k"
1507 
1508 #define ELF_ARCH	 bfd_arch_ip2k
1509 #define ELF_MACHINE_CODE EM_IP2K
1510 #define ELF_MACHINE_ALT1 EM_IP2K_OLD
1511 #define ELF_MAXPAGESIZE  1 /* No pages on the IP2K.  */
1512 
1513 #define elf_info_to_howto_rel			NULL
1514 #define elf_info_to_howto			ip2k_info_to_howto_rela
1515 
1516 #define elf_backend_can_gc_sections		1
1517 #define elf_backend_rela_normal			1
1518 #define elf_backend_relocate_section		ip2k_elf_relocate_section
1519 
1520 #define elf_symbol_leading_char			'_'
1521 #define bfd_elf32_bfd_reloc_type_lookup		ip2k_reloc_type_lookup
1522 #define bfd_elf32_bfd_reloc_name_lookup	ip2k_reloc_name_lookup
1523 #define bfd_elf32_bfd_relax_section		ip2k_elf_relax_section
1524 
1525 #include "elf32-target.h"
1526