2 * ELF file handling for TCC
4 * Copyright (c) 2001-2004 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library 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 GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 /* XXX: avoid static variable */
24 static int new_undef_sym
= 0; /* Is there a new undefined sym since last new_undef_sym() */
26 ST_FUNC
int put_elf_str(Section
*s
, const char *sym
)
31 len
= strlen(sym
) + 1;
32 offset
= s
->data_offset
;
33 ptr
= section_ptr_add(s
, len
);
34 memcpy(ptr
, sym
, len
);
38 /* elf symbol hashing function */
39 static unsigned long elf_hash(const unsigned char *name
)
41 unsigned long h
= 0, g
;
44 h
= (h
<< 4) + *name
++;
53 /* rebuild hash table of section s */
54 /* NOTE: we do factorize the hash table code to go faster */
55 static void rebuild_hash(Section
*s
, unsigned int nb_buckets
)
58 int *ptr
, *hash
, nb_syms
, sym_index
, h
;
59 unsigned char *strtab
;
61 strtab
= s
->link
->data
;
62 nb_syms
= s
->data_offset
/ sizeof(ElfW(Sym
));
64 s
->hash
->data_offset
= 0;
65 ptr
= section_ptr_add(s
->hash
, (2 + nb_buckets
+ nb_syms
) * sizeof(int));
70 memset(hash
, 0, (nb_buckets
+ 1) * sizeof(int));
71 ptr
+= nb_buckets
+ 1;
73 sym
= (ElfW(Sym
) *)s
->data
+ 1;
74 for(sym_index
= 1; sym_index
< nb_syms
; sym_index
++) {
75 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
76 h
= elf_hash(strtab
+ sym
->st_name
) % nb_buckets
;
87 /* return the symbol number */
88 ST_FUNC
int put_elf_sym(Section
*s
, addr_t value
, unsigned long size
,
89 int info
, int other
, int shndx
, const char *name
)
91 int name_offset
, sym_index
;
96 sym
= section_ptr_add(s
, sizeof(ElfW(Sym
)));
98 name_offset
= put_elf_str(s
->link
, name
);
101 /* XXX: endianness */
102 sym
->st_name
= name_offset
;
103 sym
->st_value
= value
;
106 sym
->st_other
= other
;
107 sym
->st_shndx
= shndx
;
108 sym_index
= sym
- (ElfW(Sym
) *)s
->data
;
112 ptr
= section_ptr_add(hs
, sizeof(int));
113 base
= (int *)hs
->data
;
114 /* only add global or weak symbols */
115 if (ELFW(ST_BIND
)(info
) != STB_LOCAL
) {
116 /* add another hashing entry */
118 h
= elf_hash((unsigned char *) name
) % nbuckets
;
120 base
[2 + h
] = sym_index
;
122 /* we resize the hash table */
123 hs
->nb_hashed_syms
++;
124 if (hs
->nb_hashed_syms
> 2 * nbuckets
) {
125 rebuild_hash(s
, 2 * nbuckets
);
135 /* find global ELF symbol 'name' and return its index. Return 0 if not
137 ST_FUNC
int find_elf_sym(Section
*s
, const char *name
)
141 int nbuckets
, sym_index
, h
;
147 nbuckets
= ((int *)hs
->data
)[0];
148 h
= elf_hash((unsigned char *) name
) % nbuckets
;
149 sym_index
= ((int *)hs
->data
)[2 + h
];
150 while (sym_index
!= 0) {
151 sym
= &((ElfW(Sym
) *)s
->data
)[sym_index
];
152 name1
= (char *) s
->link
->data
+ sym
->st_name
;
153 if (!strcmp(name
, name1
))
155 sym_index
= ((int *)hs
->data
)[2 + nbuckets
+ sym_index
];
160 /* return elf symbol value, signal error if 'err' is nonzero */
161 ST_FUNC addr_t
get_elf_sym_addr(TCCState
*s
, const char *name
, int err
)
166 sym_index
= find_elf_sym(s
->symtab
, name
);
167 sym
= &((ElfW(Sym
) *)s
->symtab
->data
)[sym_index
];
168 if (!sym_index
|| sym
->st_shndx
== SHN_UNDEF
) {
170 tcc_error("%s not defined", name
);
173 return sym
->st_value
;
176 /* return elf symbol value */
177 LIBTCCAPI
void *tcc_get_symbol(TCCState
*s
, const char *name
)
179 return (void*)(uintptr_t)get_elf_sym_addr(s
, name
, 0);
182 #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
183 /* return elf symbol value or error */
184 ST_FUNC
void* tcc_get_symbol_err(TCCState
*s
, const char *name
)
186 return (void*)(uintptr_t)get_elf_sym_addr(s
, name
, 1);
190 /* add an elf symbol : check if it is already defined and patch
191 it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
192 ST_FUNC
int add_elf_sym(Section
*s
, addr_t value
, unsigned long size
,
193 int info
, int other
, int sh_num
, const char *name
)
196 int sym_bind
, sym_index
, sym_type
, esym_bind
;
197 unsigned char sym_vis
, esym_vis
, new_vis
;
199 sym_bind
= ELFW(ST_BIND
)(info
);
200 sym_type
= ELFW(ST_TYPE
)(info
);
201 sym_vis
= ELFW(ST_VISIBILITY
)(other
);
203 if (sym_bind
!= STB_LOCAL
) {
204 /* we search global or weak symbols */
205 sym_index
= find_elf_sym(s
, name
);
208 esym
= &((ElfW(Sym
) *)s
->data
)[sym_index
];
209 if (esym
->st_shndx
!= SHN_UNDEF
) {
210 esym_bind
= ELFW(ST_BIND
)(esym
->st_info
);
211 /* propagate the most constraining visibility */
212 /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
213 esym_vis
= ELFW(ST_VISIBILITY
)(esym
->st_other
);
214 if (esym_vis
== STV_DEFAULT
) {
216 } else if (sym_vis
== STV_DEFAULT
) {
219 new_vis
= (esym_vis
< sym_vis
) ? esym_vis
: sym_vis
;
221 esym
->st_other
= (esym
->st_other
& ~ELFW(ST_VISIBILITY
)(-1))
223 other
= esym
->st_other
; /* in case we have to patch esym */
224 if (sh_num
== SHN_UNDEF
) {
225 /* ignore adding of undefined symbol if the
226 corresponding symbol is already defined */
227 } else if (sym_bind
== STB_GLOBAL
&& esym_bind
== STB_WEAK
) {
228 /* global overrides weak, so patch */
230 } else if (sym_bind
== STB_WEAK
&& esym_bind
== STB_GLOBAL
) {
231 /* weak is ignored if already global */
232 } else if (sym_bind
== STB_WEAK
&& esym_bind
== STB_WEAK
) {
233 /* keep first-found weak definition, ignore subsequents */
234 } else if (sym_vis
== STV_HIDDEN
|| sym_vis
== STV_INTERNAL
) {
235 /* ignore hidden symbols after */
236 } else if (esym
->st_shndx
== SHN_COMMON
237 && (sh_num
< SHN_LORESERVE
|| sh_num
== SHN_COMMON
)) {
238 /* gr: Happens with 'tcc ... -static tcctest.c' on e.g. Ubuntu 6.01
239 No idea if this is the correct solution ... */
241 } else if (s
== tcc_state
->dynsymtab_section
) {
242 /* we accept that two DLL define the same symbol */
245 printf("new_bind=%x new_shndx=%x new_vis=%x old_bind=%x old_shndx=%x old_vis=%x\n",
246 sym_bind
, sh_num
, new_vis
, esym_bind
, esym
->st_shndx
, esym_vis
);
248 tcc_error_noabort("'%s' defined twice", name
);
252 esym
->st_info
= ELFW(ST_INFO
)(sym_bind
, sym_type
);
253 esym
->st_shndx
= sh_num
;
255 esym
->st_value
= value
;
256 esym
->st_size
= size
;
257 esym
->st_other
= other
;
261 sym_index
= put_elf_sym(s
, value
, size
,
262 ELFW(ST_INFO
)(sym_bind
, sym_type
), other
,
269 ST_FUNC
void put_elf_reloc(Section
*symtab
, Section
*s
, unsigned long offset
,
270 int type
, int symbol
)
278 /* if no relocation section, create it */
279 snprintf(buf
, sizeof(buf
), REL_SECTION_FMT
, s
->name
);
280 /* if the symtab is allocated, then we consider the relocation
282 sr
= new_section(tcc_state
, buf
, SHT_RELX
, symtab
->sh_flags
);
283 sr
->sh_entsize
= sizeof(ElfW_Rel
);
285 sr
->sh_info
= s
->sh_num
;
288 rel
= section_ptr_add(sr
, sizeof(ElfW_Rel
));
289 rel
->r_offset
= offset
;
290 rel
->r_info
= ELFW(R_INFO
)(symbol
, type
);
291 #ifdef TCC_TARGET_X86_64
296 /* put stab debug information */
298 ST_FUNC
void put_stabs(const char *str
, int type
, int other
, int desc
,
303 sym
= section_ptr_add(stab_section
, sizeof(Stab_Sym
));
305 sym
->n_strx
= put_elf_str(stabstr_section
, str
);
310 sym
->n_other
= other
;
312 sym
->n_value
= value
;
315 ST_FUNC
void put_stabs_r(const char *str
, int type
, int other
, int desc
,
316 unsigned long value
, Section
*sec
, int sym_index
)
318 put_stabs(str
, type
, other
, desc
, value
);
319 put_elf_reloc(symtab_section
, stab_section
,
320 stab_section
->data_offset
- sizeof(unsigned int),
321 R_DATA_32
, sym_index
);
324 ST_FUNC
void put_stabn(int type
, int other
, int desc
, int value
)
326 put_stabs(NULL
, type
, other
, desc
, value
);
329 ST_FUNC
void put_stabd(int type
, int other
, int desc
)
331 put_stabs(NULL
, type
, other
, desc
, 0);
334 /* Browse each elem of type <type> in section <sec> starting at elem <startoff>
335 using variable <elem> */
336 #define for_each_elem(sec, startoff, elem, type) \
337 for (elem = (type *) sec->data + startoff; \
338 elem < (type *) (sec->data + sec->data_offset); elem++)
340 /* In an ELF file symbol table, the local symbols must appear below
341 the global and weak ones. Since TCC cannot sort it while generating
342 the code, we must do it after. All the relocation tables are also
343 modified to take into account the symbol table sorting */
344 static void sort_syms(TCCState
*s1
, Section
*s
)
346 int *old_to_new_syms
;
354 nb_syms
= s
->data_offset
/ sizeof(ElfW(Sym
));
355 new_syms
= tcc_malloc(nb_syms
* sizeof(ElfW(Sym
)));
356 old_to_new_syms
= tcc_malloc(nb_syms
* sizeof(int));
358 /* first pass for local symbols */
359 p
= (ElfW(Sym
) *)s
->data
;
361 for(i
= 0; i
< nb_syms
; i
++) {
362 if (ELFW(ST_BIND
)(p
->st_info
) == STB_LOCAL
) {
363 old_to_new_syms
[i
] = q
- new_syms
;
368 /* save the number of local symbols in section header */
369 s
->sh_info
= q
- new_syms
;
371 /* then second pass for non local symbols */
372 p
= (ElfW(Sym
) *)s
->data
;
373 for(i
= 0; i
< nb_syms
; i
++) {
374 if (ELFW(ST_BIND
)(p
->st_info
) != STB_LOCAL
) {
375 old_to_new_syms
[i
] = q
- new_syms
;
381 /* we copy the new symbols to the old */
382 memcpy(s
->data
, new_syms
, nb_syms
* sizeof(ElfW(Sym
)));
385 /* now we modify all the relocations */
386 for(i
= 1; i
< s1
->nb_sections
; i
++) {
387 sr
= s1
->sections
[i
];
388 if (sr
->sh_type
== SHT_RELX
&& sr
->link
== s
) {
389 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
390 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
391 type
= ELFW(R_TYPE
)(rel
->r_info
);
392 sym_index
= old_to_new_syms
[sym_index
];
393 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
398 tcc_free(old_to_new_syms
);
401 /* relocate common symbols in the .bss section */
402 ST_FUNC
void relocate_common_syms(void)
405 unsigned long offset
, align
;
407 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
408 if (sym
->st_shndx
== SHN_COMMON
) {
410 align
= sym
->st_value
;
411 offset
= bss_section
->data_offset
;
412 offset
= (offset
+ align
- 1) & -align
;
413 sym
->st_value
= offset
;
414 sym
->st_shndx
= bss_section
->sh_num
;
415 offset
+= sym
->st_size
;
416 bss_section
->data_offset
= offset
;
421 /* relocate symbol table, resolve undefined symbols if do_resolve is
422 true and output error if undefined symbol. */
423 ST_FUNC
void relocate_syms(TCCState
*s1
, int do_resolve
)
425 ElfW(Sym
) *sym
, *esym
;
426 int sym_bind
, sh_num
, sym_index
;
429 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
430 sh_num
= sym
->st_shndx
;
431 if (sh_num
== SHN_UNDEF
) {
432 name
= (char *) strtab_section
->data
+ sym
->st_name
;
433 /* Use ld.so to resolve symbol for us (for tcc -run) */
435 #if defined TCC_IS_NATIVE && !defined _WIN32
437 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
438 addr
= resolve_sym(s1
, name
);
440 sym
->st_value
= (addr_t
)addr
;
444 } else if (s1
->dynsym
) {
445 /* if dynamic symbol exist, then use it */
446 sym_index
= find_elf_sym(s1
->dynsym
, name
);
448 esym
= &((ElfW(Sym
) *)s1
->dynsym
->data
)[sym_index
];
449 sym
->st_value
= esym
->st_value
;
453 /* XXX: _fp_hw seems to be part of the ABI, so we ignore
455 if (!strcmp(name
, "_fp_hw"))
457 /* only weak symbols are accepted to be undefined. Their
459 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
460 if (sym_bind
== STB_WEAK
) {
463 tcc_error_noabort("undefined symbol '%s'", name
);
465 } else if (sh_num
< SHN_LORESERVE
) {
466 /* add section base */
467 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
473 #ifdef TCC_HAS_RUNTIME_PLTGOT
474 #ifdef TCC_TARGET_X86_64
475 #define JMP_TABLE_ENTRY_SIZE 14
476 static addr_t
add_jmp_table(TCCState
*s1
, addr_t val
)
478 char *p
= s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
;
479 s1
->runtime_plt_and_got_offset
+= JMP_TABLE_ENTRY_SIZE
;
484 *(addr_t
*)(p
+ 6) = val
;
488 static addr_t
add_got_table(TCCState
*s1
, addr_t val
)
490 addr_t
*p
= (addr_t
*)(s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
);
491 s1
->runtime_plt_and_got_offset
+= sizeof(addr_t
);
495 #elif defined TCC_TARGET_ARM
496 #define JMP_TABLE_ENTRY_SIZE 8
497 static addr_t
add_jmp_table(TCCState
*s1
, int val
)
499 uint32_t *p
= (uint32_t *)(s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
);
500 s1
->runtime_plt_and_got_offset
+= JMP_TABLE_ENTRY_SIZE
;
501 /* ldr pc, [pc, #-4] */
507 #endif /* def TCC_HAS_RUNTIME_PLTGOT */
509 /* relocate a given section (CPU dependent) by applying the relocations
510 in the associated relocation section */
511 ST_FUNC
void relocate_section(TCCState
*s1
, Section
*s
)
513 Section
*sr
= s
->reloc
;
519 #if defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
520 ElfW_Rel
*qrel
= (ElfW_Rel
*) sr
->data
; /* ptr to next reloc entry reused */
524 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
525 ptr
= s
->data
+ rel
->r_offset
;
527 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
528 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
530 #ifdef TCC_TARGET_X86_64
531 val
+= rel
->r_addend
;
533 type
= ELFW(R_TYPE
)(rel
->r_info
);
534 addr
= s
->sh_addr
+ rel
->r_offset
;
538 #if defined(TCC_TARGET_I386)
540 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
541 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
542 qrel
->r_offset
= rel
->r_offset
;
544 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_386_32
);
548 qrel
->r_info
= ELFW(R_INFO
)(0, R_386_RELATIVE
);
555 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
557 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
559 qrel
->r_offset
= rel
->r_offset
;
560 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_386_PC32
);
565 *(int *)ptr
+= val
- addr
;
568 *(int *)ptr
+= val
- addr
;
575 *(int *)ptr
+= s1
->got
->sh_addr
- addr
;
578 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
581 /* we load the got offset */
582 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
585 if (s1
->output_format
!= TCC_OUTPUT_FORMAT_BINARY
) {
587 tcc_error("can only produce 16-bit binary files");
589 *(short *)ptr
+= val
;
592 if (s1
->output_format
!= TCC_OUTPUT_FORMAT_BINARY
)
594 *(short *)ptr
+= val
- addr
;
596 #elif defined(TCC_TARGET_ARM)
602 int x
, is_thumb
, is_call
, h
, blx_avail
, is_bl
, th_ko
;
603 x
= (*(int *) ptr
) & 0xffffff;
604 (*(int *)ptr
) &= 0xff000000;
608 blx_avail
= (TCC_ARM_VERSION
>= 5);
610 is_bl
= (*(unsigned *) ptr
) >> 24 == 0xeb;
611 is_call
= (type
== R_ARM_CALL
|| (type
== R_ARM_PC24
&& is_bl
));
614 th_ko
= (x
& 3) && (!blx_avail
|| !is_call
);
615 #ifdef TCC_HAS_RUNTIME_PLTGOT
616 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
617 if (th_ko
|| x
>= 0x2000000 || x
< -0x2000000) {
618 x
+= add_jmp_table(s1
, val
) - val
; /* add veneer */
619 th_ko
= (x
& 3) && (!blx_avail
|| !is_call
);
620 is_thumb
= 0; /* Veneer uses ARM instructions */
624 if (th_ko
|| x
>= 0x2000000 || x
< -0x2000000)
625 tcc_error("can't relocate value at %x",addr
);
628 /* Only reached if blx is avail and it is a call */
631 (*(int *)ptr
) = 0xfa << 24; /* bl -> blx */
636 /* Since these relocations only concern Thumb-2 and blx instruction was
637 introduced before Thumb-2, we can assume blx is available and not
640 case R_ARM_THM_JUMP24
:
642 int x
, hi
, lo
, s
, j1
, j2
, i1
, i2
, imm10
, imm11
;
643 int to_thumb
, is_call
, to_plt
, blx_bit
= 1 << 12;
647 if (sym
->st_shndx
== SHN_UNDEF
&&
648 ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
651 /* Get initial offset */
652 hi
= (*(uint16_t *)ptr
);
653 lo
= (*(uint16_t *)(ptr
+2));
661 x
= (s
<< 24) | (i1
<< 23) | (i2
<< 22) |
662 (imm10
<< 12) | (imm11
<< 1);
666 /* Relocation infos */
669 to_plt
= (val
>= plt
->sh_addr
) &&
670 (val
< plt
->sh_addr
+ plt
->data_offset
);
671 is_call
= (type
== R_ARM_THM_PC22
);
673 /* Compute final offset */
674 if (to_plt
&& !is_call
) /* Point to 1st instr of Thumb stub */
677 if (!to_thumb
&& is_call
) {
678 blx_bit
= 0; /* bl -> blx */
679 x
= (x
+ 3) & -4; /* Compute offset from aligned PC */
682 /* Check that relocation is possible
683 * offset must not be out of range
684 * if target is to be entered in arm mode:
686 - instruction must be a call (bl) or a jump to PLT */
687 if (!to_thumb
|| x
>= 0x1000000 || x
< -0x1000000)
688 if (to_thumb
|| (val
& 2) || (!is_call
&& !to_plt
))
689 tcc_error("can't relocate value at %x",addr
);
691 /* Compute and store final offset */
697 imm10
= (x
>> 12) & 0x3ff;
698 imm11
= (x
>> 1) & 0x7ff;
699 (*(uint16_t *)ptr
) = (uint16_t) ((hi
& 0xf800) |
701 (*(uint16_t *)(ptr
+2)) = (uint16_t) ((lo
& 0xc000) |
702 (j1
<< 13) | blx_bit
| (j2
<< 11) |
707 case R_ARM_MOVW_ABS_NC
:
710 if (type
== R_ARM_MOVT_ABS
)
713 imm4
= (val
>> 12) & 0xf;
714 x
= (imm4
<< 16) | imm12
;
715 if (type
== R_ARM_THM_MOVT_ABS
)
721 case R_ARM_THM_MOVT_ABS
:
722 case R_ARM_THM_MOVW_ABS_NC
:
724 int x
, i
, imm4
, imm3
, imm8
;
725 if (type
== R_ARM_THM_MOVT_ABS
)
728 imm3
= (val
>> 8) & 0x7;
730 imm4
= (val
>> 12) & 0xf;
731 x
= (imm3
<< 28) | (imm8
<< 16) | (i
<< 10) | imm4
;
732 if (type
== R_ARM_THM_MOVT_ABS
)
741 x
= (*(int *)ptr
) & 0x7fffffff;
742 (*(int *)ptr
) &= 0x80000000;
745 if((x
^(x
>>1))&0x40000000)
746 tcc_error("can't relocate value at %x",addr
);
747 (*(int *)ptr
) |= x
& 0x7fffffff;
753 *(int *)ptr
+= val
- addr
;
756 *(int *)ptr
+= s1
->got
->sh_addr
- addr
;
759 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
762 /* we load the got offset */
763 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
768 /* trade Thumb support for ARMv4 support */
769 if ((0x0ffffff0 & *(int*)ptr
) == 0x012FFF10)
770 *(int*)ptr
^= 0xE12FFF10 ^ 0xE1A0F000; /* BX Rm -> MOV PC, Rm */
773 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
774 type
, (unsigned)addr
, ptr
, (unsigned)val
);
776 #elif defined(TCC_TARGET_C67)
784 /* put the low 16 bits of the absolute address
785 add to what is already there */
787 orig
= ((*(int *)(ptr
)) >> 7) & 0xffff;
788 orig
|= (((*(int *)(ptr
+4)) >> 7) & 0xffff) << 16;
790 /* patch both at once - assumes always in pairs Low - High */
792 *(int *) ptr
= (*(int *) ptr
& (~(0xffff << 7)) ) | (((val
+orig
) & 0xffff) << 7);
793 *(int *)(ptr
+4) = (*(int *)(ptr
+4) & (~(0xffff << 7)) ) | ((((val
+orig
)>>16) & 0xffff) << 7);
799 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
800 type
, (unsigned)addr
, ptr
, (unsigned)val
);
802 #elif defined(TCC_TARGET_X86_64)
804 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
805 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
806 qrel
->r_offset
= rel
->r_offset
;
808 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_64
);
809 qrel
->r_addend
= rel
->r_addend
;
813 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
814 qrel
->r_addend
= *(long long *)ptr
+ val
;
818 *(long long *)ptr
+= val
;
822 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
823 /* XXX: this logic may depend on TCC's codegen
824 now TCC uses R_X86_64_32 even for a 64bit pointer */
825 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
826 qrel
->r_addend
= *(int *)ptr
+ val
;
833 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
835 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
837 qrel
->r_offset
= rel
->r_offset
;
838 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_PC32
);
839 qrel
->r_addend
= *(int *)ptr
;
847 /* We've put the PLT slot offset into r_addend when generating
848 it, and that's what we must use as relocation value (adjusted
849 by section offset of course). */
850 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
851 val
= s1
->plt
->sh_addr
+ rel
->r_addend
;
857 diff
= (long long)val
- addr
;
858 if (diff
<= -2147483647 || diff
> 2147483647) {
859 #ifdef TCC_HAS_RUNTIME_PLTGOT
860 /* XXX: naive support for over 32bit jump */
861 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
862 val
= (add_jmp_table(s1
, val
- rel
->r_addend
) +
867 if (diff
<= -2147483647 || diff
> 2147483647) {
868 tcc_error("internal error: relocation failed");
874 case R_X86_64_GLOB_DAT
:
875 case R_X86_64_JUMP_SLOT
:
876 /* They don't need addend */
877 *(int *)ptr
= val
- rel
->r_addend
;
879 case R_X86_64_GOTPCREL
:
880 #ifdef TCC_HAS_RUNTIME_PLTGOT
881 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
882 val
= add_got_table(s1
, val
- rel
->r_addend
) + rel
->r_addend
;
883 *(int *)ptr
+= val
- addr
;
887 *(int *)ptr
+= (s1
->got
->sh_addr
- addr
+
888 s1
->sym_attrs
[sym_index
].got_offset
- 4);
890 case R_X86_64_GOTTPOFF
:
891 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
894 /* we load the got offset */
895 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
898 #error unsupported processor
902 /* if the relocation is allocated, we change its symbol table */
903 if (sr
->sh_flags
& SHF_ALLOC
)
904 sr
->link
= s1
->dynsym
;
907 /* relocate relocation table in 'sr' */
908 static void relocate_rel(TCCState
*s1
, Section
*sr
)
913 s
= s1
->sections
[sr
->sh_info
];
914 for_each_elem(sr
, 0, rel
, ElfW_Rel
)
915 rel
->r_offset
+= s
->sh_addr
;
918 /* count the number of dynamic relocations so that we can reserve
920 static int prepare_dynamic_rel(TCCState
*s1
, Section
*sr
)
923 int sym_index
, esym_index
, type
, count
;
926 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
927 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
928 type
= ELFW(R_TYPE
)(rel
->r_info
);
930 #if defined(TCC_TARGET_I386)
932 #elif defined(TCC_TARGET_X86_64)
939 #if defined(TCC_TARGET_I386)
941 #elif defined(TCC_TARGET_X86_64)
944 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
953 /* allocate the section */
954 sr
->sh_flags
|= SHF_ALLOC
;
955 sr
->sh_size
= count
* sizeof(ElfW_Rel
);
960 static struct sym_attr
*alloc_sym_attr(TCCState
*s1
, int index
)
963 struct sym_attr
*tab
;
965 if (index
>= s1
->nb_sym_attrs
) {
966 /* find immediately bigger power of 2 and reallocate array */
970 tab
= tcc_realloc(s1
->sym_attrs
, n
* sizeof(*s1
->sym_attrs
));
972 memset(s1
->sym_attrs
+ s1
->nb_sym_attrs
, 0,
973 (n
- s1
->nb_sym_attrs
) * sizeof(*s1
->sym_attrs
));
974 s1
->nb_sym_attrs
= n
;
976 return &s1
->sym_attrs
[index
];
979 /* XXX: suppress that */
980 static void put32(unsigned char *p
, uint32_t val
)
988 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
989 defined(TCC_TARGET_X86_64)
990 static uint32_t get32(unsigned char *p
)
992 return p
[0] | (p
[1] << 8) | (p
[2] << 16) | (p
[3] << 24);
996 static void build_got(TCCState
*s1
)
1000 /* if no got, then create it */
1001 s1
->got
= new_section(s1
, ".got", SHT_PROGBITS
, SHF_ALLOC
| SHF_WRITE
);
1002 s1
->got
->sh_entsize
= 4;
1003 add_elf_sym(symtab_section
, 0, 4, ELFW(ST_INFO
)(STB_GLOBAL
, STT_OBJECT
),
1004 0, s1
->got
->sh_num
, "_GLOBAL_OFFSET_TABLE_");
1005 ptr
= section_ptr_add(s1
->got
, 3 * PTR_SIZE
);
1007 /* keep space for _DYNAMIC pointer, if present */
1009 /* two dummy got entries */
1013 /* keep space for _DYNAMIC pointer, if present */
1016 /* two dummy got entries */
1024 /* put a got or plt entry corresponding to a symbol in symtab_section. 'size'
1025 and 'info' can be modifed if more precise info comes from the DLL.
1026 Returns offset of GOT or PLT slot. */
1027 static unsigned long put_got_entry(TCCState
*s1
,
1028 int reloc_type
, unsigned long size
, int info
,
1031 int index
, need_plt_entry
;
1034 unsigned long offset
;
1036 struct sym_attr
*symattr
;
1041 need_plt_entry
= s1
->dynsym
&&
1042 #ifdef TCC_TARGET_X86_64
1043 (reloc_type
== R_X86_64_JUMP_SLOT
);
1044 #elif defined(TCC_TARGET_I386)
1045 (reloc_type
== R_386_JMP_SLOT
);
1046 #elif defined(TCC_TARGET_ARM)
1047 (reloc_type
== R_ARM_JUMP_SLOT
);
1052 /* If a got/plt entry already exists for that symbol, no need to add one */
1053 if (sym_index
< s1
->nb_sym_attrs
) {
1054 if (need_plt_entry
&& s1
->sym_attrs
[sym_index
].plt_offset
)
1055 return s1
->sym_attrs
[sym_index
].plt_offset
;
1056 else if (!need_plt_entry
&& s1
->sym_attrs
[sym_index
].got_offset
)
1057 return s1
->sym_attrs
[sym_index
].got_offset
;
1060 symattr
= alloc_sym_attr(s1
, sym_index
);
1062 /* Only store the GOT offset if it's not generated for the PLT entry. */
1063 if (!need_plt_entry
)
1064 symattr
->got_offset
= s1
->got
->data_offset
;
1067 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1068 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1069 offset
= sym
->st_value
;
1070 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1071 if (need_plt_entry
) {
1075 unsigned long relofs
;
1077 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1080 /* if we build a DLL, we add a %ebx offset */
1081 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1087 /* add a PLT entry */
1089 if (plt
->data_offset
== 0) {
1090 /* first plt entry */
1091 p
= section_ptr_add(plt
, 16);
1092 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1093 p
[1] = modrm
+ 0x10;
1094 put32(p
+ 2, PTR_SIZE
);
1095 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1097 put32(p
+ 8, PTR_SIZE
* 2);
1100 /* The PLT slot refers to the relocation entry it needs
1101 via offset. The reloc entry is created below, so its
1102 offset is the current data_offset. */
1103 relofs
= s1
->got
->reloc
? s1
->got
->reloc
->data_offset
: 0;
1104 symattr
->plt_offset
= plt
->data_offset
;
1105 p
= section_ptr_add(plt
, 16);
1106 p
[0] = 0xff; /* jmp *(got + x) */
1108 put32(p
+ 2, s1
->got
->data_offset
);
1109 p
[6] = 0x68; /* push $xxx */
1110 #ifdef TCC_TARGET_X86_64
1111 /* On x86-64, the relocation is referred to by _index_. */
1112 put32(p
+ 7, relofs
/ sizeof (ElfW_Rel
));
1114 put32(p
+ 7, relofs
);
1116 p
[11] = 0xe9; /* jmp plt_start */
1117 put32(p
+ 12, -(plt
->data_offset
));
1119 /* If this was an UNDEF symbol set the offset in the
1120 dynsymtab to the PLT slot, so that PC32 relocs to it
1122 if (sym
->st_shndx
== SHN_UNDEF
)
1123 offset
= plt
->data_offset
- 16;
1125 #elif defined(TCC_TARGET_ARM)
1126 if (need_plt_entry
) {
1130 /* if we build a DLL, we add a %ebx offset */
1131 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1132 tcc_error("DLLs unimplemented!");
1134 /* add a PLT entry */
1136 if (plt
->data_offset
== 0) {
1137 /* first plt entry */
1138 p
= section_ptr_add(plt
, 16);
1139 put32(p
, 0xe52de004); /* push {lr} */
1140 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1141 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1142 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1145 symattr
->plt_offset
= plt
->data_offset
;
1146 if (symattr
->plt_thumb_stub
) {
1147 p
= section_ptr_add(plt
, 20);
1148 put32(p
, 0x4778); /* bx pc */
1149 put32(p
+2, 0x46c0); /* nop */
1152 p
= section_ptr_add(plt
, 16);
1153 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1154 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1155 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1156 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1158 /* the symbol is modified so that it will be relocated to
1160 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1161 offset
= plt
->data_offset
- 16;
1163 #elif defined(TCC_TARGET_C67)
1164 tcc_error("C67 got not implemented");
1166 #error unsupported CPU
1168 /* XXX This might generate multiple syms for name. */
1169 index
= put_elf_sym(s1
->dynsym
, offset
,
1170 size
, info
, 0, sym
->st_shndx
, name
);
1171 /* Create the relocation (it's against the GOT for PLT
1173 put_elf_reloc(s1
->dynsym
, s1
->got
,
1174 s1
->got
->data_offset
,
1177 /* Without .dynsym (i.e. static link or memory output) we
1178 still need relocs against the generated got, so as to fill
1179 the entries with the symbol values (determined later). */
1180 put_elf_reloc(symtab_section
, s1
->got
,
1181 s1
->got
->data_offset
,
1182 reloc_type
, sym_index
);
1184 /* And now create the GOT slot itself. */
1185 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1188 return symattr
->plt_offset
;
1190 return symattr
->got_offset
;
1193 /* build GOT and PLT entries */
1194 ST_FUNC
void build_got_entries(TCCState
*s1
)
1199 int i
, type
, reloc_type
, sym_index
;
1201 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1202 s
= s1
->sections
[i
];
1203 if (s
->sh_type
!= SHT_RELX
)
1205 /* no need to handle got relocations */
1206 if (s
->link
!= symtab_section
)
1208 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1209 type
= ELFW(R_TYPE
)(rel
->r_info
);
1211 #if defined(TCC_TARGET_I386)
1218 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1219 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1220 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1221 /* look at the symbol got offset. If none, then add one */
1222 if (type
== R_386_GOT32
)
1223 reloc_type
= R_386_GLOB_DAT
;
1225 reloc_type
= R_386_JMP_SLOT
;
1226 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1230 #elif defined(TCC_TARGET_ARM)
1237 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1238 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1239 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1240 /* look at the symbol got offset. If none, then add one */
1241 if (type
== R_ARM_GOT32
)
1242 reloc_type
= R_ARM_GLOB_DAT
;
1244 reloc_type
= R_ARM_JUMP_SLOT
;
1245 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1249 case R_ARM_THM_JUMP24
:
1250 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1251 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1252 /* We are relocating a jump from thumb code to arm code */
1253 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1256 char *name
, buf
[1024];
1257 Section
*text_section
;
1259 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1260 text_section
= s1
->sections
[sym
->st_shndx
];
1261 /* Modify reloc to target a thumb stub to switch to ARM */
1262 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1263 index
= put_elf_sym(symtab_section
,
1264 text_section
->data_offset
+ 1,
1265 sym
->st_size
, sym
->st_info
, 0,
1266 sym
->st_shndx
, buf
);
1267 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1268 /* Create a thumb stub fonction to switch to ARM mode */
1269 put_elf_reloc(symtab_section
, text_section
,
1270 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1272 p
= section_ptr_add(text_section
, 8);
1273 put32(p
, 0x4778); /* bx pc */
1274 put32(p
+2, 0x46c0); /* nop */
1275 put32(p
+4, 0xeafffffe); /* b $sym */
1277 #elif defined(TCC_TARGET_C67)
1284 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1285 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1286 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1287 /* look at the symbol got offset. If none, then add one */
1288 if (type
== R_C60_GOT32
)
1289 reloc_type
= R_C60_GLOB_DAT
;
1291 reloc_type
= R_C60_JMP_SLOT
;
1292 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1296 #elif defined(TCC_TARGET_X86_64)
1297 case R_X86_64_GOT32
:
1298 case R_X86_64_GOTTPOFF
:
1299 case R_X86_64_GOTPCREL
:
1300 case R_X86_64_PLT32
:
1303 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1304 type
== R_X86_64_PLT32
) {
1306 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1307 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1308 /* look at the symbol got offset. If none, then add one */
1309 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1310 reloc_type
= R_X86_64_GLOB_DAT
;
1312 reloc_type
= R_X86_64_JUMP_SLOT
;
1313 ofs
= put_got_entry(s1
, reloc_type
, sym
->st_size
,
1314 sym
->st_info
, sym_index
);
1315 if (type
== R_X86_64_PLT32
1316 && s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1317 /* We store the place of the generated PLT slot
1319 rel
->r_addend
+= ofs
;
1323 #error unsupported CPU
1332 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1333 const char *symtab_name
, int sh_type
, int sh_flags
,
1334 const char *strtab_name
,
1335 const char *hash_name
, int hash_sh_flags
)
1337 Section
*symtab
, *strtab
, *hash
;
1338 int *ptr
, nb_buckets
;
1340 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1341 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1342 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1343 put_elf_str(strtab
, "");
1344 symtab
->link
= strtab
;
1345 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1349 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1350 hash
->sh_entsize
= sizeof(int);
1351 symtab
->hash
= hash
;
1352 hash
->link
= symtab
;
1354 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1355 ptr
[0] = nb_buckets
;
1357 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1361 /* put dynamic tag */
1362 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1365 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1367 dyn
->d_un
.d_val
= val
;
1370 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1374 char sym_start
[1024];
1377 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1378 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1380 s
= find_section(s1
, section_name
);
1385 end_offset
= s
->data_offset
;
1388 add_elf_sym(symtab_section
,
1390 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1391 s
->sh_num
, sym_start
);
1392 add_elf_sym(symtab_section
,
1394 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1395 s
->sh_num
, sym_end
);
1398 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1400 #ifdef CONFIG_TCC_BCHECK
1402 Section
*init_section
;
1403 unsigned char *pinit
;
1406 if (0 == s1
->do_bounds_check
)
1409 /* XXX: add an object file to do that */
1410 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1412 add_elf_sym(symtab_section
, 0, 0,
1413 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1414 bounds_section
->sh_num
, "__bounds_start");
1415 #ifdef TCC_TARGET_I386
1416 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1417 /* add 'call __bound_init()' in .init section */
1418 init_section
= find_section(s1
, ".init");
1419 pinit
= section_ptr_add(init_section
, 5);
1421 put32(pinit
+ 1, -4);
1422 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1423 put_elf_reloc(symtab_section
, init_section
,
1424 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1430 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1433 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1434 return tcc_add_file(s1
, buf
);
1437 /* add tcc runtime libraries */
1438 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1441 if (!s1
->nostdlib
) {
1442 tcc_add_library(s1
, "c");
1443 #ifdef CONFIG_USE_LIBGCC
1444 if (!s1
->static_link
) {
1445 tcc_add_file(s1
, TCC_LIBGCC
);
1446 tcc_add_support(s1
, "libtcc1.a");
1448 tcc_add_support(s1
, "libtcc1.a");
1450 tcc_add_support(s1
, "libtcc1.a");
1454 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1455 libtcc1.a must be loaded before for __bound_init to be defined and
1456 crtn.o must be loaded after to not finalize _init too early. */
1459 if (!s1
->nostdlib
) {
1460 /* add crt end if not memory output */
1461 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1462 tcc_add_crt(s1
, "crtn.o");
1466 /* add various standard linker symbols (must be done after the
1467 sections are filled (for example after allocating common
1469 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1475 add_elf_sym(symtab_section
,
1476 text_section
->data_offset
, 0,
1477 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1478 text_section
->sh_num
, "_etext");
1479 add_elf_sym(symtab_section
,
1480 data_section
->data_offset
, 0,
1481 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1482 data_section
->sh_num
, "_edata");
1483 add_elf_sym(symtab_section
,
1484 bss_section
->data_offset
, 0,
1485 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1486 bss_section
->sh_num
, "_end");
1487 /* horrible new standard ldscript defines */
1488 add_init_array_defines(s1
, ".preinit_array");
1489 add_init_array_defines(s1
, ".init_array");
1490 add_init_array_defines(s1
, ".fini_array");
1492 /* add start and stop symbols for sections whose name can be
1494 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1495 s
= s1
->sections
[i
];
1496 if (s
->sh_type
== SHT_PROGBITS
&&
1497 (s
->sh_flags
& SHF_ALLOC
)) {
1501 /* check if section name can be expressed in C */
1507 if (!isid(ch
) && !isnum(ch
))
1511 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1512 add_elf_sym(symtab_section
,
1514 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1516 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1517 add_elf_sym(symtab_section
,
1519 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1526 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1527 const int *sec_order
)
1530 int i
, offset
, size
;
1533 for(i
=1;i
<s1
->nb_sections
;i
++) {
1534 s
= s1
->sections
[sec_order
[i
]];
1535 if (s
->sh_type
!= SHT_NOBITS
&&
1536 (s
->sh_flags
& SHF_ALLOC
)) {
1537 while (offset
< s
->sh_offset
) {
1542 fwrite(s
->data
, 1, size
, f
);
1548 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1550 #define EXTRA_RELITEMS 14
1552 /* move the relocation value from .dynsym to .got */
1553 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1555 uint32_t *gotd
= (void *)s1
->got
->data
;
1558 gotd
+= 3; /* dummy entries in .got */
1559 /* relocate symbols in .dynsym */
1560 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1561 if (sym
->st_shndx
== SHN_UNDEF
) {
1562 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1569 #define EXTRA_RELITEMS 9
1571 /* zero plt offsets of weak symbols in .dynsym */
1572 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1576 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1577 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1582 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1584 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1585 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1586 unsigned long offset
;
1588 if (sym_index
>= s1
->nb_sym_attrs
)
1590 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1591 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1592 #ifdef TCC_TARGET_X86_64
1593 /* only works for x86-64 */
1594 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1596 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1599 /* Perform relocation to GOT or PLTÂ entries */
1600 ST_FUNC
void fill_got(TCCState
*s1
)
1606 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1607 s
= s1
->sections
[i
];
1608 if (s
->sh_type
!= SHT_RELX
)
1610 /* no need to handle got relocations */
1611 if (s
->link
!= symtab_section
)
1613 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1614 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1615 case R_X86_64_GOT32
:
1616 case R_X86_64_GOTPCREL
:
1617 case R_X86_64_PLT32
:
1618 fill_got_entry(s1
, rel
);
1625 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1626 in shared libraries and export non local defined symbols to shared libraries
1627 if -rdynamic switch was given on command line */
1628 static void bind_exe_dynsyms(TCCState
*s1
)
1631 int sym_index
, index
;
1632 ElfW(Sym
) *sym
, *esym
;
1635 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1636 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1637 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1638 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1639 if (sym
->st_shndx
== SHN_UNDEF
) {
1640 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1641 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1643 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1644 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1645 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1646 /* Indirect functions shall have STT_FUNC type in executable
1647 * dynsym section. Indeed, a dlsym call following a lazy
1648 * resolution would pick the symbol value from the
1649 * executable dynsym entry which would contain the address
1650 * of the function wanted by the caller of dlsym instead of
1651 * the address of the function that would return that
1653 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1654 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1655 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1656 } else if (type
== STT_OBJECT
) {
1657 unsigned long offset
;
1659 offset
= bss_section
->data_offset
;
1660 /* XXX: which alignment ? */
1661 offset
= (offset
+ 16 - 1) & -16;
1662 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1663 esym
->st_info
, 0, bss_section
->sh_num
,
1665 /* Ensure R_COPY works for weak symbol aliases */
1666 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1667 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1668 if ((dynsym
->st_value
== esym
->st_value
)
1669 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1670 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1672 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1674 bss_section
->sh_num
, dynname
);
1679 put_elf_reloc(s1
->dynsym
, bss_section
,
1680 offset
, R_COPY
, index
);
1681 offset
+= esym
->st_size
;
1682 bss_section
->data_offset
= offset
;
1685 /* STB_WEAK undefined symbols are accepted */
1686 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1687 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1688 !strcmp(name
, "_fp_hw")) {
1690 tcc_error_noabort("undefined symbol '%s'", name
);
1693 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1694 /* if -rdynamic option, then export all non local symbols */
1695 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1696 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1697 0, sym
->st_shndx
, name
);
1702 /* Bind symbols of libraries: export non local symbols of executable that
1703 resolve undefined symbols of shared libraries */
1704 static void bind_libs_dynsyms(TCCState
*s1
)
1708 ElfW(Sym
) *sym
, *esym
;
1710 /* now look at unresolved dynamic symbols and export
1711 corresponding symbol */
1712 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1713 if (esym
->st_shndx
== SHN_UNDEF
) {
1714 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1715 sym_index
= find_elf_sym(symtab_section
, name
);
1717 /* XXX: avoid adding a symbol if already present because of
1719 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1720 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1721 sym
->st_info
, 0, sym
->st_shndx
, name
);
1723 /* weak symbols can stay undefined */
1724 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1725 tcc_warning("undefined dynamic symbol '%s'", name
);
1731 /* Export all non local symbols (for shared libraries) */
1732 static void export_global_syms(TCCState
*s1
)
1734 int nb_syms
, dynindex
, index
;
1738 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1739 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1740 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1741 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1742 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1743 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1744 sym
->st_info
, 0, sym
->st_shndx
, name
);
1745 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1746 s1
->symtab_to_dynsym
[index
] = dynindex
;
1751 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1752 address for PLT and GOT are known (see fill_program_header) */
1753 static void relocate_plt(TCCState
*s1
)
1758 p_end
= p
+ s1
->plt
->data_offset
;
1760 #if defined(TCC_TARGET_I386)
1761 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1762 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1765 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1768 #elif defined(TCC_TARGET_X86_64)
1769 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1770 put32(p
+ 2, get32(p
+ 2) + x
);
1771 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1774 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1777 #elif defined(TCC_TARGET_ARM)
1779 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1782 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1784 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1787 #elif defined(TCC_TARGET_C67)
1790 #error unsupported CPU
1795 /* Allocate strings for section names and decide if an unallocated section
1798 NOTE: the strsec section comes last, so its size is also correct ! */
1799 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1804 /* Allocate strings for section names */
1805 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1806 s
= s1
->sections
[i
];
1807 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1808 /* when generating a DLL, we include relocations but we may
1810 if (file_type
== TCC_OUTPUT_DLL
&&
1811 s
->sh_type
== SHT_RELX
&&
1812 !(s
->sh_flags
& SHF_ALLOC
)) {
1813 /* gr: avoid bogus relocs for empty (debug) sections */
1814 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1815 prepare_dynamic_rel(s1
, s
);
1816 else if (s1
->do_debug
)
1817 s
->sh_size
= s
->data_offset
;
1818 } else if (s1
->do_debug
||
1819 file_type
== TCC_OUTPUT_OBJ
||
1820 (s
->sh_flags
& SHF_ALLOC
) ||
1821 i
== (s1
->nb_sections
- 1)) {
1822 /* we output all sections if debug or object file */
1823 s
->sh_size
= s
->data_offset
;
1828 /* Info to be copied in dynamic section */
1832 unsigned long dyn_rel_off
;
1835 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1841 /* Assign sections to segments and decide how are sections laid out when loaded
1842 in memory. This function also fills corresponding program headers. */
1843 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1844 Section
*interp
, struct dyn_inf
*dyninf
,
1847 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1853 file_type
= s1
->output_type
;
1855 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1856 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1861 if (s1
->has_text_addr
) {
1862 int a_offset
, p_offset
;
1863 addr
= s1
->text_addr
;
1864 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1866 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1867 p_offset
= file_offset
& (s1
->section_align
- 1);
1868 if (a_offset
< p_offset
)
1869 a_offset
+= s1
->section_align
;
1870 file_offset
+= (a_offset
- p_offset
);
1872 if (file_type
== TCC_OUTPUT_DLL
)
1875 addr
= ELF_START_ADDR
;
1876 /* compute address after headers */
1877 addr
+= (file_offset
& (s1
->section_align
- 1));
1881 /* Leave one program headers for the program interpreter and one for
1882 the program header table itself if needed. These are done later as
1883 they require section layout to be done first. */
1885 ph
+= 1 + HAVE_PHDR
;
1887 /* dynamic relocation table information, for .dynamic section */
1888 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1889 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1890 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1893 for(j
= 0; j
< 2; j
++) {
1894 ph
->p_type
= PT_LOAD
;
1896 ph
->p_flags
= PF_R
| PF_X
;
1898 ph
->p_flags
= PF_R
| PF_W
;
1899 ph
->p_align
= s1
->section_align
;
1901 /* Decide the layout of sections loaded in memory. This must
1902 be done before program headers are filled since they contain
1903 info about the layout. We do the following ordering: interp,
1904 symbol tables, relocations, progbits, nobits */
1905 /* XXX: do faster and simpler sorting */
1906 for(k
= 0; k
< 5; k
++) {
1907 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1908 s
= s1
->sections
[i
];
1909 /* compute if section should be included */
1911 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1915 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1916 (SHF_ALLOC
| SHF_WRITE
))
1922 } else if (s
->sh_type
== SHT_DYNSYM
||
1923 s
->sh_type
== SHT_STRTAB
||
1924 s
->sh_type
== SHT_HASH
) {
1927 } else if (s
->sh_type
== SHT_RELX
) {
1930 } else if (s
->sh_type
== SHT_NOBITS
) {
1937 sec_order
[sh_order_index
++] = i
;
1939 /* section matches: we align it and add its size */
1941 addr
= (addr
+ s
->sh_addralign
- 1) &
1942 ~(s
->sh_addralign
- 1);
1943 file_offset
+= (int) ( addr
- tmp
);
1944 s
->sh_offset
= file_offset
;
1947 /* update program header infos */
1948 if (ph
->p_offset
== 0) {
1949 ph
->p_offset
= file_offset
;
1951 ph
->p_paddr
= ph
->p_vaddr
;
1953 /* update dynamic relocation infos */
1954 if (s
->sh_type
== SHT_RELX
) {
1955 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1956 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1957 dyninf
->rel_addr
= addr
;
1958 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1960 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1961 dyninf
->bss_addr
= addr
;
1962 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1965 if (dyninf
->rel_size
== 0)
1966 dyninf
->rel_addr
= addr
;
1967 dyninf
->rel_size
+= s
->sh_size
;
1971 if (s
->sh_type
!= SHT_NOBITS
)
1972 file_offset
+= s
->sh_size
;
1976 /* Make the first PT_LOAD segment include the program
1977 headers itself (and the ELF header as well), it'll
1978 come out with same memory use but will make various
1979 tools like binutils strip work better. */
1980 ph
->p_offset
&= ~(ph
->p_align
- 1);
1981 ph
->p_vaddr
&= ~(ph
->p_align
- 1);
1982 ph
->p_paddr
&= ~(ph
->p_align
- 1);
1984 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1985 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1988 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1989 /* if in the middle of a page, we duplicate the page in
1990 memory so that one copy is RX and the other is RW */
1991 if ((addr
& (s1
->section_align
- 1)) != 0)
1992 addr
+= s1
->section_align
;
1994 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1995 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1996 ~(s1
->section_align
- 1);
2002 /* all other sections come after */
2003 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2004 s
= s1
->sections
[i
];
2005 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
2007 sec_order
[sh_order_index
++] = i
;
2009 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
2010 ~(s
->sh_addralign
- 1);
2011 s
->sh_offset
= file_offset
;
2012 if (s
->sh_type
!= SHT_NOBITS
)
2013 file_offset
+= s
->sh_size
;
2019 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
2024 /* if interpreter, then add corresponding program header */
2030 int len
= phnum
* sizeof(ElfW(Phdr
));
2032 ph
->p_type
= PT_PHDR
;
2033 ph
->p_offset
= sizeof(ElfW(Ehdr
));
2034 ph
->p_vaddr
= interp
->sh_addr
- len
;
2035 ph
->p_paddr
= ph
->p_vaddr
;
2036 ph
->p_filesz
= ph
->p_memsz
= len
;
2037 ph
->p_flags
= PF_R
| PF_X
;
2038 ph
->p_align
= 4; /* interp->sh_addralign; */
2042 ph
->p_type
= PT_INTERP
;
2043 ph
->p_offset
= interp
->sh_offset
;
2044 ph
->p_vaddr
= interp
->sh_addr
;
2045 ph
->p_paddr
= ph
->p_vaddr
;
2046 ph
->p_filesz
= interp
->sh_size
;
2047 ph
->p_memsz
= interp
->sh_size
;
2049 ph
->p_align
= interp
->sh_addralign
;
2052 /* if dynamic section, then add corresponding program header */
2054 ph
= &phdr
[phnum
- 1];
2056 ph
->p_type
= PT_DYNAMIC
;
2057 ph
->p_offset
= dynamic
->sh_offset
;
2058 ph
->p_vaddr
= dynamic
->sh_addr
;
2059 ph
->p_paddr
= ph
->p_vaddr
;
2060 ph
->p_filesz
= dynamic
->sh_size
;
2061 ph
->p_memsz
= dynamic
->sh_size
;
2062 ph
->p_flags
= PF_R
| PF_W
;
2063 ph
->p_align
= dynamic
->sh_addralign
;
2067 /* Fill the dynamic section with tags describing the address and size of
2069 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2073 dynamic
= dyninf
->dynamic
;
2075 /* put dynamic section entries */
2076 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2077 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2078 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2079 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2080 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2081 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2082 #ifdef TCC_TARGET_X86_64
2083 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2084 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2085 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2087 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2088 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2089 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2090 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2091 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2092 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2093 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2095 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2096 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2097 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2101 put_dt(dynamic
, DT_DEBUG
, 0);
2102 put_dt(dynamic
, DT_NULL
, 0);
2105 /* Relocate remaining sections and symbols (that is those not related to
2107 static int final_sections_reloc(TCCState
*s1
)
2112 relocate_syms(s1
, 0);
2114 if (s1
->nb_errors
!= 0)
2117 /* relocate sections */
2118 /* XXX: ignore sections with allocated relocations ? */
2119 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2120 s
= s1
->sections
[i
];
2121 if (s
->reloc
&& s
!= s1
->got
)
2122 relocate_section(s1
, s
);
2125 /* relocate relocation entries if the relocation tables are
2126 allocated in the executable */
2127 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2128 s
= s1
->sections
[i
];
2129 if ((s
->sh_flags
& SHF_ALLOC
) &&
2130 s
->sh_type
== SHT_RELX
) {
2131 relocate_rel(s1
, s
);
2137 /* Create an ELF file on disk.
2138 This function handle ELF specific layout requirements */
2139 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2140 int file_offset
, int *sec_order
)
2142 int i
, shnum
, offset
, size
, file_type
;
2145 ElfW(Shdr
) shdr
, *sh
;
2147 file_type
= s1
->output_type
;
2148 shnum
= s1
->nb_sections
;
2150 memset(&ehdr
, 0, sizeof(ehdr
));
2153 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2154 ehdr
.e_phnum
= phnum
;
2155 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2159 file_offset
= (file_offset
+ 3) & -4;
2162 ehdr
.e_ident
[0] = ELFMAG0
;
2163 ehdr
.e_ident
[1] = ELFMAG1
;
2164 ehdr
.e_ident
[2] = ELFMAG2
;
2165 ehdr
.e_ident
[3] = ELFMAG3
;
2166 ehdr
.e_ident
[4] = ELFCLASSW
;
2167 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2168 ehdr
.e_ident
[6] = EV_CURRENT
;
2169 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2170 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2172 #ifdef TCC_TARGET_ARM
2174 ehdr
.e_ident
[EI_OSABI
] = 0;
2175 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2176 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2177 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2178 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2179 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2181 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2183 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2188 case TCC_OUTPUT_EXE
:
2189 ehdr
.e_type
= ET_EXEC
;
2190 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2192 case TCC_OUTPUT_DLL
:
2193 ehdr
.e_type
= ET_DYN
;
2194 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2196 case TCC_OUTPUT_OBJ
:
2197 ehdr
.e_type
= ET_REL
;
2200 ehdr
.e_machine
= EM_TCC_TARGET
;
2201 ehdr
.e_version
= EV_CURRENT
;
2202 ehdr
.e_shoff
= file_offset
;
2203 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2204 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2205 ehdr
.e_shnum
= shnum
;
2206 ehdr
.e_shstrndx
= shnum
- 1;
2208 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2209 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2210 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2212 sort_syms(s1
, symtab_section
);
2213 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2214 s
= s1
->sections
[sec_order
[i
]];
2215 if (s
->sh_type
!= SHT_NOBITS
) {
2216 if (s
->sh_type
== SHT_DYNSYM
)
2217 patch_dynsym_undef(s1
, s
);
2218 while (offset
< s
->sh_offset
) {
2223 fwrite(s
->data
, 1, size
, f
);
2228 /* output section headers */
2229 while (offset
< ehdr
.e_shoff
) {
2234 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2236 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2237 s
= s1
->sections
[i
];
2239 sh
->sh_name
= s
->sh_name
;
2240 sh
->sh_type
= s
->sh_type
;
2241 sh
->sh_flags
= s
->sh_flags
;
2242 sh
->sh_entsize
= s
->sh_entsize
;
2243 sh
->sh_info
= s
->sh_info
;
2245 sh
->sh_link
= s
->link
->sh_num
;
2246 sh
->sh_addralign
= s
->sh_addralign
;
2247 sh
->sh_addr
= s
->sh_addr
;
2248 sh
->sh_offset
= s
->sh_offset
;
2249 sh
->sh_size
= s
->sh_size
;
2251 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2255 /* Write an elf, coff or "binary" file */
2256 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2257 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2259 int fd
, mode
, file_type
;
2262 file_type
= s1
->output_type
;
2263 if (file_type
== TCC_OUTPUT_OBJ
)
2268 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2270 tcc_error_noabort("could not write '%s'", filename
);
2273 f
= fdopen(fd
, "wb");
2275 printf("<- %s\n", filename
);
2277 #ifdef TCC_TARGET_COFF
2278 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2279 tcc_output_coff(s1
, f
);
2282 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2283 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2285 tcc_output_binary(s1
, f
, sec_order
);
2291 /* Output an elf, coff or binary file */
2292 /* XXX: suppress unneeded sections */
2293 static int elf_output_file(TCCState
*s1
, const char *filename
)
2295 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2296 struct dyn_inf dyninf
;
2299 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2301 file_type
= s1
->output_type
;
2304 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2305 if (file_type
!= TCC_OUTPUT_OBJ
) {
2306 tcc_add_runtime(s1
);
2311 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2312 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2314 if (file_type
!= TCC_OUTPUT_OBJ
) {
2315 relocate_common_syms();
2317 tcc_add_linker_symbols(s1
);
2319 if (!s1
->static_link
) {
2320 if (file_type
== TCC_OUTPUT_EXE
) {
2322 /* allow override the dynamic loader */
2323 const char *elfint
= getenv("LD_SO");
2325 elfint
= DEFAULT_ELFINTERP(s1
);
2326 /* add interpreter section only if executable */
2327 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2328 interp
->sh_addralign
= 1;
2329 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2330 strcpy(ptr
, elfint
);
2333 /* add dynamic symbol table */
2334 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2336 ".hash", SHF_ALLOC
);
2337 dynstr
= s1
->dynsym
->link
;
2339 /* add dynamic section */
2340 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2341 SHF_ALLOC
| SHF_WRITE
);
2342 dynamic
->link
= dynstr
;
2343 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2346 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2347 SHF_ALLOC
| SHF_EXECINSTR
);
2348 s1
->plt
->sh_entsize
= 4;
2352 if (file_type
== TCC_OUTPUT_EXE
) {
2353 bind_exe_dynsyms(s1
);
2355 if (s1
->nb_errors
) {
2360 bind_libs_dynsyms(s1
);
2361 } else /* shared library case: simply export all global symbols */
2362 export_global_syms(s1
);
2364 build_got_entries(s1
);
2366 /* add a list of needed dlls */
2367 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2368 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2369 if (dllref
->level
== 0)
2370 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2374 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2376 /* XXX: currently, since we do not handle PIC code, we
2377 must relocate the readonly segments */
2378 if (file_type
== TCC_OUTPUT_DLL
) {
2380 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2381 put_dt(dynamic
, DT_TEXTREL
, 0);
2385 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2387 /* add necessary space for other entries */
2388 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2389 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2391 /* still need to build got entries in case of static link */
2392 build_got_entries(s1
);
2396 /* we add a section for symbols */
2397 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2398 put_elf_str(strsec
, "");
2400 /* compute number of sections */
2401 shnum
= s1
->nb_sections
;
2403 /* this array is used to reorder sections in the output file */
2404 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2407 /* compute number of program headers */
2410 case TCC_OUTPUT_OBJ
:
2413 case TCC_OUTPUT_EXE
:
2414 if (!s1
->static_link
)
2415 phnum
= 4 + HAVE_PHDR
;
2419 case TCC_OUTPUT_DLL
:
2424 /* Allocate strings for section names */
2425 alloc_sec_names(s1
, file_type
, strsec
);
2427 /* allocate program segment headers */
2428 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2430 /* compute section to program header mapping */
2431 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2433 /* Fill remaining program header and finalize relocation related to dynamic
2436 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2438 dyninf
.dynamic
= dynamic
;
2439 dyninf
.dynstr
= dynstr
;
2441 fill_dynamic(s1
, &dyninf
);
2443 /* put in GOT the dynamic section address and relocate PLT */
2444 put32(s1
->got
->data
, dynamic
->sh_addr
);
2445 if (file_type
== TCC_OUTPUT_EXE
2446 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2447 || file_type
== TCC_OUTPUT_DLL
2452 /* relocate symbols in .dynsym now that final addresses are known */
2453 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2454 /* relocate to PLT if symbol corresponds to a PLT entry */
2455 if (sym
->st_shndx
== SHN_UNDEF
) {
2457 sym
->st_value
+= s1
->plt
->sh_addr
;
2458 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2459 /* do symbol relocation */
2460 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2466 /* if building executable or DLL, then relocate each section
2467 except the GOT which is already relocated */
2468 if (file_type
!= TCC_OUTPUT_OBJ
) {
2469 ret
= final_sections_reloc(s1
);
2474 /* Perform relocation to GOT or PLTÂ entries */
2475 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2478 /* Create the ELF file with name 'filename' */
2479 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2481 tcc_free(s1
->symtab_to_dynsym
);
2482 tcc_free(sec_order
);
2484 tcc_free(s1
->sym_attrs
);
2485 s1
->sym_attrs
= NULL
;
2489 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2492 #ifdef TCC_TARGET_PE
2493 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2494 ret
= pe_output_file(s
, filename
);
2497 ret
= elf_output_file(s
, filename
);
2501 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2505 data
= tcc_malloc(size
);
2506 lseek(fd
, file_offset
, SEEK_SET
);
2507 read(fd
, data
, size
);
2511 typedef struct SectionMergeInfo
{
2512 Section
*s
; /* corresponding existing section */
2513 unsigned long offset
; /* offset of the new section in the existing section */
2514 uint8_t new_section
; /* true if section 's' was added */
2515 uint8_t link_once
; /* true if link once section */
2518 /* load an object file and merge it with current files */
2519 /* XXX: handle correctly stab (debug) info */
2520 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2521 int fd
, unsigned long file_offset
)
2524 ElfW(Shdr
) *shdr
, *sh
;
2525 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2526 unsigned char *strsec
, *strtab
;
2527 int *old_to_new_syms
;
2528 char *sh_name
, *name
;
2529 SectionMergeInfo
*sm_table
, *sm
;
2530 ElfW(Sym
) *sym
, *symtab
;
2537 stab_index
= stabstr_index
= 0;
2539 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2541 if (ehdr
.e_ident
[0] != ELFMAG0
||
2542 ehdr
.e_ident
[1] != ELFMAG1
||
2543 ehdr
.e_ident
[2] != ELFMAG2
||
2544 ehdr
.e_ident
[3] != ELFMAG3
)
2546 /* test if object file */
2547 if (ehdr
.e_type
!= ET_REL
)
2549 /* test CPU specific stuff */
2550 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2551 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2553 tcc_error_noabort("invalid object file");
2557 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2558 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2559 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2561 /* load section names */
2562 sh
= &shdr
[ehdr
.e_shstrndx
];
2563 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2565 /* load symtab and strtab */
2566 old_to_new_syms
= NULL
;
2570 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2572 if (sh
->sh_type
== SHT_SYMTAB
) {
2574 tcc_error_noabort("object must contain only one symtab");
2579 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2580 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2581 sm_table
[i
].s
= symtab_section
;
2583 /* now load strtab */
2584 sh
= &shdr
[sh
->sh_link
];
2585 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2589 /* now examine each section and try to merge its content with the
2591 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2592 /* no need to examine section name strtab */
2593 if (i
== ehdr
.e_shstrndx
)
2596 sh_name
= (char *) strsec
+ sh
->sh_name
;
2597 /* ignore sections types we do not handle */
2598 if (sh
->sh_type
!= SHT_PROGBITS
&&
2599 sh
->sh_type
!= SHT_RELX
&&
2601 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2603 sh
->sh_type
!= SHT_NOBITS
&&
2604 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2605 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2606 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2607 strcmp(sh_name
, ".stabstr")
2610 if (sh
->sh_addralign
< 1)
2611 sh
->sh_addralign
= 1;
2612 /* find corresponding section, if any */
2613 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2614 s
= s1
->sections
[j
];
2615 if (!strcmp(s
->name
, sh_name
)) {
2616 if (!strncmp(sh_name
, ".gnu.linkonce",
2617 sizeof(".gnu.linkonce") - 1)) {
2618 /* if a 'linkonce' section is already present, we
2619 do not add it again. It is a little tricky as
2620 symbols can still be defined in
2622 sm_table
[i
].link_once
= 1;
2629 /* not found: create new section */
2630 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2631 /* take as much info as possible from the section. sh_link and
2632 sh_info will be updated later */
2633 s
->sh_addralign
= sh
->sh_addralign
;
2634 s
->sh_entsize
= sh
->sh_entsize
;
2635 sm_table
[i
].new_section
= 1;
2637 if (sh
->sh_type
!= s
->sh_type
) {
2638 tcc_error_noabort("invalid section type");
2642 /* align start of section */
2643 offset
= s
->data_offset
;
2645 if (0 == strcmp(sh_name
, ".stab")) {
2649 if (0 == strcmp(sh_name
, ".stabstr")) {
2654 size
= sh
->sh_addralign
- 1;
2655 offset
= (offset
+ size
) & ~size
;
2656 if (sh
->sh_addralign
> s
->sh_addralign
)
2657 s
->sh_addralign
= sh
->sh_addralign
;
2658 s
->data_offset
= offset
;
2660 sm_table
[i
].offset
= offset
;
2662 /* concatenate sections */
2664 if (sh
->sh_type
!= SHT_NOBITS
) {
2666 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2667 ptr
= section_ptr_add(s
, size
);
2668 read(fd
, ptr
, size
);
2670 s
->data_offset
+= size
;
2675 /* gr relocate stab strings */
2676 if (stab_index
&& stabstr_index
) {
2679 s
= sm_table
[stab_index
].s
;
2680 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2681 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2682 o
= sm_table
[stabstr_index
].offset
;
2684 a
->n_strx
+= o
, a
++;
2687 /* second short pass to update sh_link and sh_info fields of new
2689 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2691 if (!s
|| !sm_table
[i
].new_section
)
2694 if (sh
->sh_link
> 0)
2695 s
->link
= sm_table
[sh
->sh_link
].s
;
2696 if (sh
->sh_type
== SHT_RELX
) {
2697 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2698 /* update backward link */
2699 s1
->sections
[s
->sh_info
]->reloc
= s
;
2704 /* resolve symbols */
2705 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2708 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2709 if (sym
->st_shndx
!= SHN_UNDEF
&&
2710 sym
->st_shndx
< SHN_LORESERVE
) {
2711 sm
= &sm_table
[sym
->st_shndx
];
2712 if (sm
->link_once
) {
2713 /* if a symbol is in a link once section, we use the
2714 already defined symbol. It is very important to get
2715 correct relocations */
2716 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2717 name
= (char *) strtab
+ sym
->st_name
;
2718 sym_index
= find_elf_sym(symtab_section
, name
);
2720 old_to_new_syms
[i
] = sym_index
;
2724 /* if no corresponding section added, no need to add symbol */
2727 /* convert section number */
2728 sym
->st_shndx
= sm
->s
->sh_num
;
2730 sym
->st_value
+= sm
->offset
;
2733 name
= (char *) strtab
+ sym
->st_name
;
2734 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2735 sym
->st_info
, sym
->st_other
,
2736 sym
->st_shndx
, name
);
2737 old_to_new_syms
[i
] = sym_index
;
2740 /* third pass to patch relocation entries */
2741 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2746 offset
= sm_table
[i
].offset
;
2747 switch(s
->sh_type
) {
2749 /* take relocation offset information */
2750 offseti
= sm_table
[sh
->sh_info
].offset
;
2751 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2754 /* convert symbol index */
2755 type
= ELFW(R_TYPE
)(rel
->r_info
);
2756 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2757 /* NOTE: only one symtab assumed */
2758 if (sym_index
>= nb_syms
)
2760 sym_index
= old_to_new_syms
[sym_index
];
2761 /* ignore link_once in rel section. */
2762 if (!sym_index
&& !sm
->link_once
2763 #ifdef TCC_TARGET_ARM
2764 && type
!= R_ARM_V4BX
2768 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2769 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2772 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2773 /* offset the relocation offset */
2774 rel
->r_offset
+= offseti
;
2775 #ifdef TCC_TARGET_ARM
2776 /* Jumps and branches from a Thumb code to a PLT entry need
2777 special handling since PLT entries are ARM code.
2778 Unconditional bl instructions referencing PLT entries are
2779 handled by converting these instructions into blx
2780 instructions. Other case of instructions referencing a PLT
2781 entry require to add a Thumb stub before the PLT entry to
2782 switch to ARM mode. We set bit plt_thumb_stub of the
2783 attribute of a symbol to indicate such a case. */
2784 if (type
== R_ARM_THM_JUMP24
)
2785 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2798 tcc_free(old_to_new_syms
);
2805 typedef struct ArchiveHeader
{
2806 char ar_name
[16]; /* name of this member */
2807 char ar_date
[12]; /* file mtime */
2808 char ar_uid
[6]; /* owner uid; printed as decimal */
2809 char ar_gid
[6]; /* owner gid; printed as decimal */
2810 char ar_mode
[8]; /* file mode, printed as octal */
2811 char ar_size
[10]; /* file size, printed as decimal */
2812 char ar_fmag
[2]; /* should contain ARFMAG */
2815 static int get_be32(const uint8_t *b
)
2817 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2820 /* load only the objects which resolve undefined symbols */
2821 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2823 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2825 const char *ar_names
, *p
;
2826 const uint8_t *ar_index
;
2829 data
= tcc_malloc(size
);
2830 if (read(fd
, data
, size
) != size
)
2832 nsyms
= get_be32(data
);
2833 ar_index
= data
+ 4;
2834 ar_names
= (char *) ar_index
+ nsyms
* 4;
2838 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2839 sym_index
= find_elf_sym(symtab_section
, p
);
2841 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2842 if(sym
->st_shndx
== SHN_UNDEF
) {
2843 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2845 lseek(fd
, off
, SEEK_SET
);
2846 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2861 /* load a '.a' file */
2862 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2869 unsigned long file_offset
;
2871 /* skip magic which was already checked */
2872 read(fd
, magic
, sizeof(magic
));
2875 len
= read(fd
, &hdr
, sizeof(hdr
));
2878 if (len
!= sizeof(hdr
)) {
2879 tcc_error_noabort("invalid archive");
2882 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2883 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2884 size
= strtol(ar_size
, NULL
, 0);
2885 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2886 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2887 if (ar_name
[i
] != ' ')
2890 ar_name
[i
+ 1] = '\0';
2891 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2893 size
= (size
+ 1) & ~1;
2894 if (!strcmp(ar_name
, "/")) {
2895 /* coff symbol table : we handle it */
2896 if(s1
->alacarte_link
)
2897 return tcc_load_alacarte(s1
, fd
, size
);
2898 } else if (!strcmp(ar_name
, "//") ||
2899 !strcmp(ar_name
, "__.SYMDEF") ||
2900 !strcmp(ar_name
, "__.SYMDEF/") ||
2901 !strcmp(ar_name
, "ARFILENAMES/")) {
2902 /* skip symbol table or archive names */
2904 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2907 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2912 #ifndef TCC_TARGET_PE
2913 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2914 is referenced by the user (so it should be added as DT_NEEDED in
2915 the generated ELF file) */
2916 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2919 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2920 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2921 ElfW(Sym
) *sym
, *dynsym
;
2922 ElfW(Dyn
) *dt
, *dynamic
;
2923 unsigned char *dynstr
;
2924 const char *name
, *soname
;
2925 DLLReference
*dllref
;
2927 read(fd
, &ehdr
, sizeof(ehdr
));
2929 /* test CPU specific stuff */
2930 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2931 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2932 tcc_error_noabort("bad architecture");
2937 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2939 /* load dynamic section and dynamic symbols */
2943 dynsym
= NULL
; /* avoid warning */
2944 dynstr
= NULL
; /* avoid warning */
2945 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2946 switch(sh
->sh_type
) {
2948 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2949 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2952 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2953 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2954 sh1
= &shdr
[sh
->sh_link
];
2955 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2962 /* compute the real library name */
2963 soname
= tcc_basename(filename
);
2965 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2966 if (dt
->d_tag
== DT_SONAME
) {
2967 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2971 /* if the dll is already loaded, do not load it */
2972 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2973 dllref
= s1
->loaded_dlls
[i
];
2974 if (!strcmp(soname
, dllref
->name
)) {
2975 /* but update level if needed */
2976 if (level
< dllref
->level
)
2977 dllref
->level
= level
;
2983 /* add the dll and its level */
2984 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2985 dllref
->level
= level
;
2986 strcpy(dllref
->name
, soname
);
2987 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2989 /* add dynamic symbols in dynsym_section */
2990 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2991 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2992 if (sym_bind
== STB_LOCAL
)
2994 name
= (char *) dynstr
+ sym
->st_name
;
2995 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
2996 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
2999 /* load all referenced DLLs */
3000 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
3003 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
3004 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
3005 dllref
= s1
->loaded_dlls
[j
];
3006 if (!strcmp(name
, dllref
->name
))
3007 goto already_loaded
;
3009 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
3010 tcc_error_noabort("referenced dll '%s' not found", name
);
3027 #define LD_TOK_NAME 256
3028 #define LD_TOK_EOF (-1)
3030 /* return next ld script token */
3031 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
3049 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
3050 ch
= file
->buf_ptr
[0];
3058 /* case 'a' ... 'z': */
3085 /* case 'A' ... 'z': */
3120 if (!((ch
>= 'a' && ch
<= 'z') ||
3121 (ch
>= 'A' && ch
<= 'Z') ||
3122 (ch
>= '0' && ch
<= '9') ||
3123 strchr("/.-_+=$:\\,~", ch
)))
3125 if ((q
- name
) < name_size
- 1) {
3144 static int ld_add_file(TCCState
*s1
, const char filename
[])
3148 ret
= tcc_add_file_internal(s1
, filename
, 0);
3150 ret
= tcc_add_dll(s1
, filename
, 0);
3154 static inline int new_undef_syms(void)
3157 ret
= new_undef_sym
;
3162 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3164 char filename
[1024], libname
[1024];
3165 int t
, group
, nblibs
= 0, ret
= 0;
3168 group
= !strcmp(cmd
, "GROUP");
3171 t
= ld_next(s1
, filename
, sizeof(filename
));
3174 t
= ld_next(s1
, filename
, sizeof(filename
));
3177 if (t
== LD_TOK_EOF
) {
3178 tcc_error_noabort("unexpected end of file");
3180 goto lib_parse_error
;
3181 } else if (t
== ')') {
3183 } else if (t
== '-') {
3184 t
= ld_next(s1
, filename
, sizeof(filename
));
3185 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3186 tcc_error_noabort("library name expected");
3188 goto lib_parse_error
;
3190 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3191 if (s1
->static_link
) {
3192 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3194 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3196 } else if (t
!= LD_TOK_NAME
) {
3197 tcc_error_noabort("filename expected");
3199 goto lib_parse_error
;
3201 if (!strcmp(filename
, "AS_NEEDED")) {
3202 ret
= ld_add_file_list(s1
, cmd
, 1);
3204 goto lib_parse_error
;
3206 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3208 ret
= ld_add_file(s1
, filename
);
3210 goto lib_parse_error
;
3212 /* Add the filename *and* the libname to avoid future conversions */
3213 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3214 if (libname
[0] != '\0')
3215 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3219 t
= ld_next(s1
, filename
, sizeof(filename
));
3221 t
= ld_next(s1
, filename
, sizeof(filename
));
3224 if (group
&& !as_needed
) {
3225 while (new_undef_syms()) {
3228 for (i
= 0; i
< nblibs
; i
++)
3229 ld_add_file(s1
, libs
[i
]);
3233 dynarray_reset(&libs
, &nblibs
);
3237 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3239 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3242 char filename
[1024];
3245 ch
= file
->buf_ptr
[0];
3248 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3249 if (t
== LD_TOK_EOF
)
3251 else if (t
!= LD_TOK_NAME
)
3253 if (!strcmp(cmd
, "INPUT") ||
3254 !strcmp(cmd
, "GROUP")) {
3255 ret
= ld_add_file_list(s1
, cmd
, 0);
3258 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3259 !strcmp(cmd
, "TARGET")) {
3260 /* ignore some commands */
3261 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3265 t
= ld_next(s1
, filename
, sizeof(filename
));
3266 if (t
== LD_TOK_EOF
) {
3267 tcc_error_noabort("unexpected end of file");
3269 } else if (t
== ')') {
3279 #endif /* !TCC_TARGET_PE */