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 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
806 qrel
->r_addend
= *(long long *)ptr
+ val
;
809 *(long long *)ptr
+= val
;
813 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
814 /* XXX: this logic may depend on TCC's codegen
815 now TCC uses R_X86_64_32 even for a 64bit pointer */
816 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
817 qrel
->r_addend
= *(int *)ptr
+ val
;
824 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
826 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
828 qrel
->r_offset
= rel
->r_offset
;
829 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_PC32
);
830 qrel
->r_addend
= *(int *)ptr
;
836 case R_X86_64_PLT32
: {
838 diff
= (long long)val
- addr
;
839 if (diff
<= -2147483647 || diff
> 2147483647) {
840 #ifdef TCC_HAS_RUNTIME_PLTGOT
841 /* XXX: naive support for over 32bit jump */
842 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
843 val
= (add_jmp_table(s1
, val
- rel
->r_addend
) +
848 if (diff
<= -2147483647 || diff
> 2147483647) {
849 tcc_error("internal error: relocation failed");
855 case R_X86_64_GLOB_DAT
:
856 case R_X86_64_JUMP_SLOT
:
857 /* They don't need addend */
858 *(int *)ptr
= val
- rel
->r_addend
;
860 case R_X86_64_GOTPCREL
:
861 #ifdef TCC_HAS_RUNTIME_PLTGOT
862 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
863 val
= add_got_table(s1
, val
- rel
->r_addend
) + rel
->r_addend
;
864 *(int *)ptr
+= val
- addr
;
868 *(int *)ptr
+= (s1
->got
->sh_addr
- addr
+
869 s1
->sym_attrs
[sym_index
].got_offset
- 4);
871 case R_X86_64_GOTTPOFF
:
872 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
875 /* we load the got offset */
876 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
879 #error unsupported processor
883 /* if the relocation is allocated, we change its symbol table */
884 if (sr
->sh_flags
& SHF_ALLOC
)
885 sr
->link
= s1
->dynsym
;
888 /* relocate relocation table in 'sr' */
889 static void relocate_rel(TCCState
*s1
, Section
*sr
)
894 s
= s1
->sections
[sr
->sh_info
];
895 for_each_elem(sr
, 0, rel
, ElfW_Rel
)
896 rel
->r_offset
+= s
->sh_addr
;
899 /* count the number of dynamic relocations so that we can reserve
901 static int prepare_dynamic_rel(TCCState
*s1
, Section
*sr
)
904 int sym_index
, esym_index
, type
, count
;
907 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
908 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
909 type
= ELFW(R_TYPE
)(rel
->r_info
);
911 #if defined(TCC_TARGET_I386)
913 #elif defined(TCC_TARGET_X86_64)
920 #if defined(TCC_TARGET_I386)
922 #elif defined(TCC_TARGET_X86_64)
925 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
934 /* allocate the section */
935 sr
->sh_flags
|= SHF_ALLOC
;
936 sr
->sh_size
= count
* sizeof(ElfW_Rel
);
941 static struct sym_attr
*alloc_sym_attr(TCCState
*s1
, int index
)
944 struct sym_attr
*tab
;
946 if (index
>= s1
->nb_sym_attrs
) {
947 /* find immediately bigger power of 2 and reallocate array */
951 tab
= tcc_realloc(s1
->sym_attrs
, n
* sizeof(*s1
->sym_attrs
));
953 memset(s1
->sym_attrs
+ s1
->nb_sym_attrs
, 0,
954 (n
- s1
->nb_sym_attrs
) * sizeof(*s1
->sym_attrs
));
955 s1
->nb_sym_attrs
= n
;
957 return &s1
->sym_attrs
[index
];
960 /* XXX: suppress that */
961 static void put32(unsigned char *p
, uint32_t val
)
969 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
970 defined(TCC_TARGET_X86_64)
971 static uint32_t get32(unsigned char *p
)
973 return p
[0] | (p
[1] << 8) | (p
[2] << 16) | (p
[3] << 24);
977 static void build_got(TCCState
*s1
)
981 /* if no got, then create it */
982 s1
->got
= new_section(s1
, ".got", SHT_PROGBITS
, SHF_ALLOC
| SHF_WRITE
);
983 s1
->got
->sh_entsize
= 4;
984 add_elf_sym(symtab_section
, 0, 4, ELFW(ST_INFO
)(STB_GLOBAL
, STT_OBJECT
),
985 0, s1
->got
->sh_num
, "_GLOBAL_OFFSET_TABLE_");
986 ptr
= section_ptr_add(s1
->got
, 3 * PTR_SIZE
);
988 /* keep space for _DYNAMIC pointer, if present */
990 /* two dummy got entries */
994 /* keep space for _DYNAMIC pointer, if present */
997 /* two dummy got entries */
1005 /* put a got entry corresponding to a symbol in symtab_section. 'size'
1006 and 'info' can be modifed if more precise info comes from the DLL */
1007 static void put_got_entry(TCCState
*s1
,
1008 int reloc_type
, unsigned long size
, int info
,
1011 int index
, need_plt_entry
, got_entry_present
= 0;
1014 unsigned long offset
;
1020 need_plt_entry
= s1
->dynsym
&&
1021 #ifdef TCC_TARGET_X86_64
1022 (reloc_type
== R_X86_64_JUMP_SLOT
);
1023 #elif defined(TCC_TARGET_I386)
1024 (reloc_type
== R_386_JMP_SLOT
);
1025 #elif defined(TCC_TARGET_ARM)
1026 (reloc_type
== R_ARM_JUMP_SLOT
);
1031 /* if a got entry already exists for that symbol, no need to add one */
1032 if (sym_index
< s1
->nb_sym_attrs
&&
1033 s1
->sym_attrs
[sym_index
].got_offset
) {
1034 if (!need_plt_entry
|| s1
->sym_attrs
[sym_index
].has_plt_entry
)
1037 got_entry_present
= 1;
1040 alloc_sym_attr(s1
, sym_index
)->got_offset
= s1
->got
->data_offset
;
1043 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1044 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1045 offset
= sym
->st_value
;
1046 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1047 if (need_plt_entry
) {
1052 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1055 /* if we build a DLL, we add a %ebx offset */
1056 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1062 /* add a PLT entry */
1064 if (plt
->data_offset
== 0) {
1065 /* first plt entry */
1066 p
= section_ptr_add(plt
, 16);
1067 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1068 p
[1] = modrm
+ 0x10;
1069 put32(p
+ 2, PTR_SIZE
);
1070 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1072 put32(p
+ 8, PTR_SIZE
* 2);
1075 p
= section_ptr_add(plt
, 16);
1076 p
[0] = 0xff; /* jmp *(got + x) */
1078 put32(p
+ 2, s1
->got
->data_offset
);
1079 p
[6] = 0x68; /* push $xxx */
1080 put32(p
+ 7, (plt
->data_offset
- 32) >> 1);
1081 p
[11] = 0xe9; /* jmp plt_start */
1082 put32(p
+ 12, -(plt
->data_offset
));
1084 /* the symbol is modified so that it will be relocated to
1086 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1087 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1089 offset
= plt
->data_offset
- 16;
1090 s1
->sym_attrs
[sym_index
].has_plt_entry
= 1;
1092 #elif defined(TCC_TARGET_ARM)
1093 if (need_plt_entry
) {
1097 /* if we build a DLL, we add a %ebx offset */
1098 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1099 tcc_error("DLLs unimplemented!");
1101 /* add a PLT entry */
1103 if (plt
->data_offset
== 0) {
1104 /* first plt entry */
1105 p
= section_ptr_add(plt
, 16);
1106 put32(p
, 0xe52de004); /* push {lr} */
1107 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1108 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1109 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1112 if (s1
->sym_attrs
[sym_index
].plt_thumb_stub
) {
1113 p
= section_ptr_add(plt
, 20);
1114 put32(p
, 0x4778); /* bx pc */
1115 put32(p
+2, 0x46c0); /* nop */
1118 p
= section_ptr_add(plt
, 16);
1119 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1120 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1121 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1122 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1124 /* the symbol is modified so that it will be relocated to
1126 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1127 offset
= plt
->data_offset
- 16;
1128 s1
->sym_attrs
[sym_index
].has_plt_entry
= 1;
1130 #elif defined(TCC_TARGET_C67)
1131 tcc_error("C67 got not implemented");
1133 #error unsupported CPU
1135 index
= put_elf_sym(s1
->dynsym
, offset
,
1136 size
, info
, 0, sym
->st_shndx
, name
);
1137 if (got_entry_present
) {
1138 put_elf_reloc(s1
->dynsym
, s1
->got
,
1139 s1
->sym_attrs
[sym_index
].got_offset
,
1144 /* put a got entry */
1145 put_elf_reloc(s1
->dynsym
, s1
->got
,
1146 s1
->got
->data_offset
,
1149 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1153 /* build GOT and PLT entries */
1154 ST_FUNC
void build_got_entries(TCCState
*s1
)
1159 int i
, type
, reloc_type
, sym_index
;
1161 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1162 s
= s1
->sections
[i
];
1163 if (s
->sh_type
!= SHT_RELX
)
1165 /* no need to handle got relocations */
1166 if (s
->link
!= symtab_section
)
1168 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1169 type
= ELFW(R_TYPE
)(rel
->r_info
);
1171 #if defined(TCC_TARGET_I386)
1178 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1179 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1180 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1181 /* look at the symbol got offset. If none, then add one */
1182 if (type
== R_386_GOT32
)
1183 reloc_type
= R_386_GLOB_DAT
;
1185 reloc_type
= R_386_JMP_SLOT
;
1186 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1190 #elif defined(TCC_TARGET_ARM)
1197 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1198 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1199 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1200 /* look at the symbol got offset. If none, then add one */
1201 if (type
== R_ARM_GOT32
)
1202 reloc_type
= R_ARM_GLOB_DAT
;
1204 reloc_type
= R_ARM_JUMP_SLOT
;
1205 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1209 case R_ARM_THM_JUMP24
:
1210 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1211 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1212 /* We are relocating a jump from thumb code to arm code */
1213 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1216 char *name
, buf
[1024];
1217 Section
*text_section
;
1219 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1220 text_section
= s1
->sections
[sym
->st_shndx
];
1221 /* Modify reloc to target a thumb stub to switch to ARM */
1222 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1223 index
= put_elf_sym(symtab_section
,
1224 text_section
->data_offset
+ 1,
1225 sym
->st_size
, sym
->st_info
, 0,
1226 sym
->st_shndx
, buf
);
1227 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1228 /* Create a thumb stub fonction to switch to ARM mode */
1229 put_elf_reloc(symtab_section
, text_section
,
1230 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1232 p
= section_ptr_add(text_section
, 8);
1233 put32(p
, 0x4778); /* bx pc */
1234 put32(p
+2, 0x46c0); /* nop */
1235 put32(p
+4, 0xeafffffe); /* b $sym */
1237 #elif defined(TCC_TARGET_C67)
1244 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1245 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1246 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1247 /* look at the symbol got offset. If none, then add one */
1248 if (type
== R_C60_GOT32
)
1249 reloc_type
= R_C60_GLOB_DAT
;
1251 reloc_type
= R_C60_JMP_SLOT
;
1252 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1256 #elif defined(TCC_TARGET_X86_64)
1257 case R_X86_64_GOT32
:
1258 case R_X86_64_GOTTPOFF
:
1259 case R_X86_64_GOTPCREL
:
1260 case R_X86_64_PLT32
:
1263 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1264 type
== R_X86_64_PLT32
) {
1265 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1266 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1267 /* look at the symbol got offset. If none, then add one */
1268 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1269 reloc_type
= R_X86_64_GLOB_DAT
;
1271 reloc_type
= R_X86_64_JUMP_SLOT
;
1272 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1277 #error unsupported CPU
1286 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1287 const char *symtab_name
, int sh_type
, int sh_flags
,
1288 const char *strtab_name
,
1289 const char *hash_name
, int hash_sh_flags
)
1291 Section
*symtab
, *strtab
, *hash
;
1292 int *ptr
, nb_buckets
;
1294 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1295 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1296 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1297 put_elf_str(strtab
, "");
1298 symtab
->link
= strtab
;
1299 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1303 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1304 hash
->sh_entsize
= sizeof(int);
1305 symtab
->hash
= hash
;
1306 hash
->link
= symtab
;
1308 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1309 ptr
[0] = nb_buckets
;
1311 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1315 /* put dynamic tag */
1316 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1319 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1321 dyn
->d_un
.d_val
= val
;
1324 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1328 char sym_start
[1024];
1331 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1332 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1334 s
= find_section(s1
, section_name
);
1339 end_offset
= s
->data_offset
;
1342 add_elf_sym(symtab_section
,
1344 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1345 s
->sh_num
, sym_start
);
1346 add_elf_sym(symtab_section
,
1348 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1349 s
->sh_num
, sym_end
);
1352 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1354 #ifdef CONFIG_TCC_BCHECK
1356 Section
*init_section
;
1357 unsigned char *pinit
;
1360 if (0 == s1
->do_bounds_check
)
1363 /* XXX: add an object file to do that */
1364 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1366 add_elf_sym(symtab_section
, 0, 0,
1367 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1368 bounds_section
->sh_num
, "__bounds_start");
1369 #ifdef TCC_TARGET_I386
1370 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1371 /* add 'call __bound_init()' in .init section */
1372 init_section
= find_section(s1
, ".init");
1373 pinit
= section_ptr_add(init_section
, 5);
1375 put32(pinit
+ 1, -4);
1376 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1377 put_elf_reloc(symtab_section
, init_section
,
1378 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1384 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1387 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1388 return tcc_add_file(s1
, buf
);
1391 /* add tcc runtime libraries */
1392 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1395 if (!s1
->nostdlib
) {
1396 tcc_add_library(s1
, "c");
1397 #ifdef CONFIG_USE_LIBGCC
1398 if (!s1
->static_link
) {
1399 tcc_add_file(s1
, TCC_LIBGCC
);
1400 tcc_add_support(s1
, "libtcc1.a");
1402 tcc_add_support(s1
, "libtcc1.a");
1404 tcc_add_support(s1
, "libtcc1.a");
1408 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1409 libtcc1.a must be loaded before for __bound_init to be defined and
1410 crtn.o must be loaded after to not finalize _init too early. */
1413 if (!s1
->nostdlib
) {
1414 /* add crt end if not memory output */
1415 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1416 tcc_add_crt(s1
, "crtn.o");
1420 /* add various standard linker symbols (must be done after the
1421 sections are filled (for example after allocating common
1423 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1429 add_elf_sym(symtab_section
,
1430 text_section
->data_offset
, 0,
1431 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1432 text_section
->sh_num
, "_etext");
1433 add_elf_sym(symtab_section
,
1434 data_section
->data_offset
, 0,
1435 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1436 data_section
->sh_num
, "_edata");
1437 add_elf_sym(symtab_section
,
1438 bss_section
->data_offset
, 0,
1439 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1440 bss_section
->sh_num
, "_end");
1441 /* horrible new standard ldscript defines */
1442 add_init_array_defines(s1
, ".preinit_array");
1443 add_init_array_defines(s1
, ".init_array");
1444 add_init_array_defines(s1
, ".fini_array");
1446 /* add start and stop symbols for sections whose name can be
1448 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1449 s
= s1
->sections
[i
];
1450 if (s
->sh_type
== SHT_PROGBITS
&&
1451 (s
->sh_flags
& SHF_ALLOC
)) {
1455 /* check if section name can be expressed in C */
1461 if (!isid(ch
) && !isnum(ch
))
1465 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1466 add_elf_sym(symtab_section
,
1468 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1470 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1471 add_elf_sym(symtab_section
,
1473 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1480 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1481 const int *sec_order
)
1484 int i
, offset
, size
;
1487 for(i
=1;i
<s1
->nb_sections
;i
++) {
1488 s
= s1
->sections
[sec_order
[i
]];
1489 if (s
->sh_type
!= SHT_NOBITS
&&
1490 (s
->sh_flags
& SHF_ALLOC
)) {
1491 while (offset
< s
->sh_offset
) {
1496 fwrite(s
->data
, 1, size
, f
);
1502 // making this evaluate to true allow valgrind to work on linux
1503 // but when compiled with debug info and then striped
1504 // the compiled programs segfault
1505 // more tought must be applyed here
1506 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1508 #define EXTRA_RELITEMS 14
1510 /* move the relocation value from .dynsym to .got */
1511 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1513 uint32_t *gotd
= (void *)s1
->got
->data
;
1516 gotd
+= 3; /* dummy entries in .got */
1517 /* relocate symbols in .dynsym */
1518 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1519 if (sym
->st_shndx
== SHN_UNDEF
) {
1520 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1527 #define EXTRA_RELITEMS 9
1529 /* zero plt offsets of weak symbols in .dynsym */
1530 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1534 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1535 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1540 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1542 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1543 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1544 unsigned long offset
;
1546 if (sym_index
>= s1
->nb_sym_attrs
)
1548 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1549 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1550 #ifdef TCC_TARGET_X86_64
1551 /* only works for x86-64 */
1552 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1554 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1557 /* Perform relocation to GOT or PLTÂ entries */
1558 ST_FUNC
void fill_got(TCCState
*s1
)
1564 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1565 s
= s1
->sections
[i
];
1566 if (s
->sh_type
!= SHT_RELX
)
1568 /* no need to handle got relocations */
1569 if (s
->link
!= symtab_section
)
1571 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1572 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1573 case R_X86_64_GOT32
:
1574 case R_X86_64_GOTPCREL
:
1575 case R_X86_64_PLT32
:
1576 fill_got_entry(s1
, rel
);
1583 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1584 in shared libraries and export non local defined symbols to shared libraries
1585 if -rdynamic switch was given on command line */
1586 static void bind_exe_dynsyms(TCCState
*s1
)
1589 int sym_index
, index
;
1590 ElfW(Sym
) *sym
, *esym
;
1593 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1594 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1595 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1596 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1597 if (sym
->st_shndx
== SHN_UNDEF
) {
1598 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1599 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1601 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1602 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1603 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1604 /* Indirect functions shall have STT_FUNC type in executable
1605 * dynsym section. Indeed, a dlsym call following a lazy
1606 * resolution would pick the symbol value from the
1607 * executable dynsym entry which would contain the address
1608 * of the function wanted by the caller of dlsym instead of
1609 * the address of the function that would return that
1611 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1612 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1613 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1614 } else if (type
== STT_OBJECT
) {
1615 unsigned long offset
;
1617 offset
= bss_section
->data_offset
;
1618 /* XXX: which alignment ? */
1619 offset
= (offset
+ 16 - 1) & -16;
1620 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1621 esym
->st_info
, 0, bss_section
->sh_num
,
1623 /* Ensure R_COPY works for weak symbol aliases */
1624 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1625 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1626 if ((dynsym
->st_value
== esym
->st_value
)
1627 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1628 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1630 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1632 bss_section
->sh_num
, dynname
);
1637 put_elf_reloc(s1
->dynsym
, bss_section
,
1638 offset
, R_COPY
, index
);
1639 offset
+= esym
->st_size
;
1640 bss_section
->data_offset
= offset
;
1643 /* STB_WEAK undefined symbols are accepted */
1644 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1645 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1646 !strcmp(name
, "_fp_hw")) {
1648 tcc_error_noabort("undefined symbol '%s'", name
);
1651 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1652 /* if -rdynamic option, then export all non local symbols */
1653 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1654 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1655 0, sym
->st_shndx
, name
);
1660 /* Bind symbols of libraries: export non local symbols of executable that
1661 resolve undefined symbols of shared libraries */
1662 static void bind_libs_dynsyms(TCCState
*s1
)
1666 ElfW(Sym
) *sym
, *esym
;
1668 /* now look at unresolved dynamic symbols and export
1669 corresponding symbol */
1670 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1671 if (esym
->st_shndx
== SHN_UNDEF
) {
1672 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1673 sym_index
= find_elf_sym(symtab_section
, name
);
1675 /* XXX: avoid adding a symbol if already present because of
1677 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1678 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1679 sym
->st_info
, 0, sym
->st_shndx
, name
);
1681 /* weak symbols can stay undefined */
1682 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1683 tcc_warning("undefined dynamic symbol '%s'", name
);
1689 /* Export all non local symbols (for shared libraries) */
1690 static void export_global_syms(TCCState
*s1
)
1692 int nb_syms
, dynindex
, index
;
1696 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1697 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1698 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1699 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1700 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1701 int type
= ELFW(ST_TYPE
)(sym
->st_info
);
1702 if ((type
== STT_FUNC
|| type
== STT_GNU_IFUNC
)
1703 && sym
->st_shndx
== SHN_UNDEF
) {
1704 int visibility
= ELFW(ST_BIND
)(sym
->st_info
);
1705 put_got_entry(s1
, R_JMP_SLOT
, sym
->st_size
,
1706 ELFW(ST_INFO
)(visibility
, STT_FUNC
),
1707 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1708 } else if (type
== STT_OBJECT
) {
1709 put_got_entry(s1
, R_X86_64_GLOB_DAT
, sym
->st_size
, sym
->st_info
,
1710 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1714 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1715 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1716 sym
->st_info
, 0, sym
->st_shndx
, name
);
1717 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1718 s1
->symtab_to_dynsym
[index
] = dynindex
;
1724 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1725 address for PLT and GOT are known (see fill_program_header) */
1726 static void relocate_plt(TCCState
*s1
)
1731 p_end
= p
+ s1
->plt
->data_offset
;
1733 #if defined(TCC_TARGET_I386)
1734 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1735 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1738 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1741 #elif defined(TCC_TARGET_X86_64)
1742 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1743 put32(p
+ 2, get32(p
+ 2) + x
);
1744 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1747 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1750 #elif defined(TCC_TARGET_ARM)
1752 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1755 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1757 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1760 #elif defined(TCC_TARGET_C67)
1763 #error unsupported CPU
1768 /* Allocate strings for section names and decide if an unallocated section
1771 NOTE: the strsec section comes last, so its size is also correct ! */
1772 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1777 /* Allocate strings for section names */
1778 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1779 s
= s1
->sections
[i
];
1780 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1781 /* when generating a DLL, we include relocations but we may
1783 if (file_type
== TCC_OUTPUT_DLL
&&
1784 s
->sh_type
== SHT_RELX
&&
1785 !(s
->sh_flags
& SHF_ALLOC
)) {
1786 /* gr: avoid bogus relocs for empty (debug) sections */
1787 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1788 prepare_dynamic_rel(s1
, s
);
1789 else if (s1
->do_debug
)
1790 s
->sh_size
= s
->data_offset
;
1791 } else if (s1
->do_debug
||
1792 file_type
== TCC_OUTPUT_OBJ
||
1793 (s
->sh_flags
& SHF_ALLOC
) ||
1794 i
== (s1
->nb_sections
- 1)) {
1795 /* we output all sections if debug or object file */
1796 s
->sh_size
= s
->data_offset
;
1801 /* Info to be copied in dynamic section */
1805 unsigned long dyn_rel_off
;
1808 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1814 /* Assign sections to segments and decide how are sections laid out when loaded
1815 in memory. This function also fills corresponding program headers. */
1816 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1817 Section
*interp
, struct dyn_inf
*dyninf
,
1820 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1826 file_type
= s1
->output_type
;
1828 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1829 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1834 if (s1
->has_text_addr
) {
1835 int a_offset
, p_offset
;
1836 addr
= s1
->text_addr
;
1837 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1839 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1840 p_offset
= file_offset
& (s1
->section_align
- 1);
1841 if (a_offset
< p_offset
)
1842 a_offset
+= s1
->section_align
;
1843 file_offset
+= (a_offset
- p_offset
);
1845 if (file_type
== TCC_OUTPUT_DLL
)
1848 addr
= ELF_START_ADDR
;
1849 /* compute address after headers */
1850 addr
+= (file_offset
& (s1
->section_align
- 1));
1854 /* Leave one program headers for the program interpreter and one for
1855 the program header table itself if needed. These are done later as
1856 they require section layout to be done first. */
1858 ph
+= 1 + HAVE_PHDR
;
1860 /* dynamic relocation table information, for .dynamic section */
1861 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1862 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1863 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1866 for(j
= 0; j
< 2; j
++) {
1867 ph
->p_type
= PT_LOAD
;
1869 ph
->p_flags
= PF_R
| PF_X
;
1871 ph
->p_flags
= PF_R
| PF_W
;
1872 ph
->p_align
= s1
->section_align
;
1874 /* Decide the layout of sections loaded in memory. This must
1875 be done before program headers are filled since they contain
1876 info about the layout. We do the following ordering: interp,
1877 symbol tables, relocations, progbits, nobits */
1878 /* XXX: do faster and simpler sorting */
1879 for(k
= 0; k
< 5; k
++) {
1880 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1881 s
= s1
->sections
[i
];
1882 /* compute if section should be included */
1884 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1888 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1889 (SHF_ALLOC
| SHF_WRITE
))
1895 } else if (s
->sh_type
== SHT_DYNSYM
||
1896 s
->sh_type
== SHT_STRTAB
||
1897 s
->sh_type
== SHT_HASH
) {
1900 } else if (s
->sh_type
== SHT_RELX
) {
1903 } else if (s
->sh_type
== SHT_NOBITS
) {
1910 sec_order
[sh_order_index
++] = i
;
1912 /* section matches: we align it and add its size */
1914 addr
= (addr
+ s
->sh_addralign
- 1) &
1915 ~(s
->sh_addralign
- 1);
1916 file_offset
+= (int) ( addr
- tmp
);
1917 s
->sh_offset
= file_offset
;
1920 /* update program header infos */
1921 if (ph
->p_offset
== 0) {
1922 ph
->p_offset
= file_offset
;
1924 ph
->p_paddr
= ph
->p_vaddr
;
1926 /* update dynamic relocation infos */
1927 if (s
->sh_type
== SHT_RELX
) {
1928 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1929 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1930 dyninf
->rel_addr
= addr
;
1931 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1933 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1934 dyninf
->bss_addr
= addr
;
1935 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1938 if (dyninf
->rel_size
== 0)
1939 dyninf
->rel_addr
= addr
;
1940 dyninf
->rel_size
+= s
->sh_size
;
1944 if (s
->sh_type
!= SHT_NOBITS
)
1945 file_offset
+= s
->sh_size
;
1948 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1949 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1952 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1953 /* if in the middle of a page, we duplicate the page in
1954 memory so that one copy is RX and the other is RW */
1955 if ((addr
& (s1
->section_align
- 1)) != 0)
1956 addr
+= s1
->section_align
;
1958 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1959 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1960 ~(s1
->section_align
- 1);
1966 /* all other sections come after */
1967 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1968 s
= s1
->sections
[i
];
1969 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
1971 sec_order
[sh_order_index
++] = i
;
1973 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
1974 ~(s
->sh_addralign
- 1);
1975 s
->sh_offset
= file_offset
;
1976 if (s
->sh_type
!= SHT_NOBITS
)
1977 file_offset
+= s
->sh_size
;
1983 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
1988 /* if interpreter, then add corresponding program header */
1994 int len
= phnum
* sizeof(ElfW(Phdr
));
1996 ph
->p_type
= PT_PHDR
;
1997 ph
->p_offset
= sizeof(ElfW(Ehdr
));
1998 ph
->p_vaddr
= interp
->sh_addr
- len
;
1999 ph
->p_paddr
= ph
->p_vaddr
;
2000 ph
->p_filesz
= ph
->p_memsz
= len
;
2001 ph
->p_flags
= PF_R
| PF_X
;
2002 ph
->p_align
= 4; /* interp->sh_addralign; */
2006 ph
->p_type
= PT_INTERP
;
2007 ph
->p_offset
= interp
->sh_offset
;
2008 ph
->p_vaddr
= interp
->sh_addr
;
2009 ph
->p_paddr
= ph
->p_vaddr
;
2010 ph
->p_filesz
= interp
->sh_size
;
2011 ph
->p_memsz
= interp
->sh_size
;
2013 ph
->p_align
= interp
->sh_addralign
;
2016 /* if dynamic section, then add corresponding program header */
2018 ph
= &phdr
[phnum
- 1];
2020 ph
->p_type
= PT_DYNAMIC
;
2021 ph
->p_offset
= dynamic
->sh_offset
;
2022 ph
->p_vaddr
= dynamic
->sh_addr
;
2023 ph
->p_paddr
= ph
->p_vaddr
;
2024 ph
->p_filesz
= dynamic
->sh_size
;
2025 ph
->p_memsz
= dynamic
->sh_size
;
2026 ph
->p_flags
= PF_R
| PF_W
;
2027 ph
->p_align
= dynamic
->sh_addralign
;
2031 /* Fill the dynamic section with tags describing the address and size of
2033 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2037 dynamic
= dyninf
->dynamic
;
2039 /* put dynamic section entries */
2040 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2041 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2042 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2043 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2044 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2045 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2046 #ifdef TCC_TARGET_X86_64
2047 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2048 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2049 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2051 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2052 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2053 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2054 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2055 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2056 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2057 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2059 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2060 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2061 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2065 put_dt(dynamic
, DT_DEBUG
, 0);
2066 put_dt(dynamic
, DT_NULL
, 0);
2069 /* Relocate remaining sections and symbols (that is those not related to
2071 static int final_sections_reloc(TCCState
*s1
)
2076 relocate_syms(s1
, 0);
2078 if (s1
->nb_errors
!= 0)
2081 /* relocate sections */
2082 /* XXX: ignore sections with allocated relocations ? */
2083 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2084 s
= s1
->sections
[i
];
2085 if (s
->reloc
&& s
!= s1
->got
)
2086 relocate_section(s1
, s
);
2089 /* relocate relocation entries if the relocation tables are
2090 allocated in the executable */
2091 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2092 s
= s1
->sections
[i
];
2093 if ((s
->sh_flags
& SHF_ALLOC
) &&
2094 s
->sh_type
== SHT_RELX
) {
2095 relocate_rel(s1
, s
);
2101 /* Create an ELF file on disk.
2102 This function handle ELF specific layout requirements */
2103 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2104 int file_offset
, int *sec_order
)
2106 int i
, shnum
, offset
, size
, file_type
;
2109 ElfW(Shdr
) shdr
, *sh
;
2111 file_type
= s1
->output_type
;
2112 shnum
= s1
->nb_sections
;
2114 memset(&ehdr
, 0, sizeof(ehdr
));
2117 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2118 ehdr
.e_phnum
= phnum
;
2119 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2123 file_offset
= (file_offset
+ 3) & -4;
2126 ehdr
.e_ident
[0] = ELFMAG0
;
2127 ehdr
.e_ident
[1] = ELFMAG1
;
2128 ehdr
.e_ident
[2] = ELFMAG2
;
2129 ehdr
.e_ident
[3] = ELFMAG3
;
2130 ehdr
.e_ident
[4] = ELFCLASSW
;
2131 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2132 ehdr
.e_ident
[6] = EV_CURRENT
;
2133 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2134 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2136 #ifdef TCC_TARGET_ARM
2138 ehdr
.e_ident
[EI_OSABI
] = 0;
2139 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2140 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2141 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2142 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2143 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2145 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2147 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2152 case TCC_OUTPUT_EXE
:
2153 ehdr
.e_type
= ET_EXEC
;
2154 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2156 case TCC_OUTPUT_DLL
:
2157 ehdr
.e_type
= ET_DYN
;
2158 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2160 case TCC_OUTPUT_OBJ
:
2161 ehdr
.e_type
= ET_REL
;
2164 ehdr
.e_machine
= EM_TCC_TARGET
;
2165 ehdr
.e_version
= EV_CURRENT
;
2166 ehdr
.e_shoff
= file_offset
;
2167 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2168 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2169 ehdr
.e_shnum
= shnum
;
2170 ehdr
.e_shstrndx
= shnum
- 1;
2172 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2173 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2174 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2176 sort_syms(s1
, symtab_section
);
2177 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2178 s
= s1
->sections
[sec_order
[i
]];
2179 if (s
->sh_type
!= SHT_NOBITS
) {
2180 if (s
->sh_type
== SHT_DYNSYM
)
2181 patch_dynsym_undef(s1
, s
);
2182 while (offset
< s
->sh_offset
) {
2187 fwrite(s
->data
, 1, size
, f
);
2192 /* output section headers */
2193 while (offset
< ehdr
.e_shoff
) {
2198 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2200 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2201 s
= s1
->sections
[i
];
2203 sh
->sh_name
= s
->sh_name
;
2204 sh
->sh_type
= s
->sh_type
;
2205 sh
->sh_flags
= s
->sh_flags
;
2206 sh
->sh_entsize
= s
->sh_entsize
;
2207 sh
->sh_info
= s
->sh_info
;
2209 sh
->sh_link
= s
->link
->sh_num
;
2210 sh
->sh_addralign
= s
->sh_addralign
;
2211 sh
->sh_addr
= s
->sh_addr
;
2212 sh
->sh_offset
= s
->sh_offset
;
2213 sh
->sh_size
= s
->sh_size
;
2215 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2219 /* Write an elf, coff or "binary" file */
2220 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2221 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2223 int fd
, mode
, file_type
;
2226 file_type
= s1
->output_type
;
2227 if (file_type
== TCC_OUTPUT_OBJ
)
2232 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2234 tcc_error_noabort("could not write '%s'", filename
);
2237 f
= fdopen(fd
, "wb");
2239 printf("<- %s\n", filename
);
2241 #ifdef TCC_TARGET_COFF
2242 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2243 tcc_output_coff(s1
, f
);
2246 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2247 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2249 tcc_output_binary(s1
, f
, sec_order
);
2255 /* Output an elf, coff or binary file */
2256 /* XXX: suppress unneeded sections */
2257 static int elf_output_file(TCCState
*s1
, const char *filename
)
2259 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2260 struct dyn_inf dyninf
;
2263 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2265 file_type
= s1
->output_type
;
2268 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2269 if (file_type
!= TCC_OUTPUT_OBJ
) {
2270 tcc_add_runtime(s1
);
2275 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2276 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2278 if (file_type
!= TCC_OUTPUT_OBJ
) {
2279 relocate_common_syms();
2281 tcc_add_linker_symbols(s1
);
2283 if (!s1
->static_link
) {
2284 if (file_type
== TCC_OUTPUT_EXE
) {
2286 /* allow override the dynamic loader */
2287 const char *elfint
= getenv("LD_SO");
2289 elfint
= DEFAULT_ELFINTERP(s1
);
2290 /* add interpreter section only if executable */
2291 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2292 interp
->sh_addralign
= 1;
2293 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2294 strcpy(ptr
, elfint
);
2297 /* add dynamic symbol table */
2298 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2300 ".hash", SHF_ALLOC
);
2301 dynstr
= s1
->dynsym
->link
;
2303 /* add dynamic section */
2304 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2305 SHF_ALLOC
| SHF_WRITE
);
2306 dynamic
->link
= dynstr
;
2307 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2310 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2311 SHF_ALLOC
| SHF_EXECINSTR
);
2312 s1
->plt
->sh_entsize
= 4;
2316 if (file_type
== TCC_OUTPUT_EXE
) {
2317 bind_exe_dynsyms(s1
);
2319 if (s1
->nb_errors
) {
2324 bind_libs_dynsyms(s1
);
2325 } else /* shared library case: simply export all global symbols */
2326 export_global_syms(s1
);
2328 build_got_entries(s1
);
2330 /* add a list of needed dlls */
2331 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2332 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2333 if (dllref
->level
== 0)
2334 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2338 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2340 /* XXX: currently, since we do not handle PIC code, we
2341 must relocate the readonly segments */
2342 if (file_type
== TCC_OUTPUT_DLL
) {
2344 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2345 put_dt(dynamic
, DT_TEXTREL
, 0);
2349 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2351 /* add necessary space for other entries */
2352 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2353 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2355 /* still need to build got entries in case of static link */
2356 build_got_entries(s1
);
2360 /* we add a section for symbols */
2361 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2362 put_elf_str(strsec
, "");
2364 /* compute number of sections */
2365 shnum
= s1
->nb_sections
;
2367 /* this array is used to reorder sections in the output file */
2368 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2371 /* compute number of program headers */
2374 case TCC_OUTPUT_OBJ
:
2377 case TCC_OUTPUT_EXE
:
2378 if (!s1
->static_link
)
2379 phnum
= 4 + HAVE_PHDR
;
2383 case TCC_OUTPUT_DLL
:
2388 /* Allocate strings for section names */
2389 alloc_sec_names(s1
, file_type
, strsec
);
2391 /* allocate program segment headers */
2392 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2394 /* compute section to program header mapping */
2395 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2397 /* Fill remaining program header and finalize relocation related to dynamic
2400 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2402 dyninf
.dynamic
= dynamic
;
2403 dyninf
.dynstr
= dynstr
;
2405 fill_dynamic(s1
, &dyninf
);
2407 /* put in GOT the dynamic section address and relocate PLT */
2408 put32(s1
->got
->data
, dynamic
->sh_addr
);
2409 if (file_type
== TCC_OUTPUT_EXE
2410 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2411 || file_type
== TCC_OUTPUT_DLL
2416 /* relocate symbols in .dynsym now that final addresses are known */
2417 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2418 /* relocate to PLT if symbol corresponds to a PLT entry */
2419 if (sym
->st_shndx
== SHN_UNDEF
) {
2421 sym
->st_value
+= s1
->plt
->sh_addr
;
2422 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2423 /* do symbol relocation */
2424 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2430 /* if building executable or DLL, then relocate each section
2431 except the GOT which is already relocated */
2432 if (file_type
!= TCC_OUTPUT_OBJ
) {
2433 ret
= final_sections_reloc(s1
);
2438 /* Perform relocation to GOT or PLTÂ entries */
2439 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2442 /* Create the ELF file with name 'filename' */
2443 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2445 tcc_free(s1
->symtab_to_dynsym
);
2446 tcc_free(sec_order
);
2448 tcc_free(s1
->sym_attrs
);
2449 s1
->sym_attrs
= NULL
;
2453 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2456 #ifdef TCC_TARGET_PE
2457 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2458 ret
= pe_output_file(s
, filename
);
2461 ret
= elf_output_file(s
, filename
);
2465 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2469 data
= tcc_malloc(size
);
2470 lseek(fd
, file_offset
, SEEK_SET
);
2471 read(fd
, data
, size
);
2475 typedef struct SectionMergeInfo
{
2476 Section
*s
; /* corresponding existing section */
2477 unsigned long offset
; /* offset of the new section in the existing section */
2478 uint8_t new_section
; /* true if section 's' was added */
2479 uint8_t link_once
; /* true if link once section */
2482 /* load an object file and merge it with current files */
2483 /* XXX: handle correctly stab (debug) info */
2484 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2485 int fd
, unsigned long file_offset
)
2488 ElfW(Shdr
) *shdr
, *sh
;
2489 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2490 unsigned char *strsec
, *strtab
;
2491 int *old_to_new_syms
;
2492 char *sh_name
, *name
;
2493 SectionMergeInfo
*sm_table
, *sm
;
2494 ElfW(Sym
) *sym
, *symtab
;
2501 stab_index
= stabstr_index
= 0;
2503 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2505 if (ehdr
.e_ident
[0] != ELFMAG0
||
2506 ehdr
.e_ident
[1] != ELFMAG1
||
2507 ehdr
.e_ident
[2] != ELFMAG2
||
2508 ehdr
.e_ident
[3] != ELFMAG3
)
2510 /* test if object file */
2511 if (ehdr
.e_type
!= ET_REL
)
2513 /* test CPU specific stuff */
2514 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2515 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2517 tcc_error_noabort("invalid object file");
2521 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2522 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2523 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2525 /* load section names */
2526 sh
= &shdr
[ehdr
.e_shstrndx
];
2527 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2529 /* load symtab and strtab */
2530 old_to_new_syms
= NULL
;
2534 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2536 if (sh
->sh_type
== SHT_SYMTAB
) {
2538 tcc_error_noabort("object must contain only one symtab");
2543 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2544 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2545 sm_table
[i
].s
= symtab_section
;
2547 /* now load strtab */
2548 sh
= &shdr
[sh
->sh_link
];
2549 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2553 /* now examine each section and try to merge its content with the
2555 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2556 /* no need to examine section name strtab */
2557 if (i
== ehdr
.e_shstrndx
)
2560 sh_name
= (char *) strsec
+ sh
->sh_name
;
2561 /* ignore sections types we do not handle */
2562 if (sh
->sh_type
!= SHT_PROGBITS
&&
2563 sh
->sh_type
!= SHT_RELX
&&
2565 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2567 sh
->sh_type
!= SHT_NOBITS
&&
2568 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2569 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2570 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2571 strcmp(sh_name
, ".stabstr")
2574 if (sh
->sh_addralign
< 1)
2575 sh
->sh_addralign
= 1;
2576 /* find corresponding section, if any */
2577 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2578 s
= s1
->sections
[j
];
2579 if (!strcmp(s
->name
, sh_name
)) {
2580 if (!strncmp(sh_name
, ".gnu.linkonce",
2581 sizeof(".gnu.linkonce") - 1)) {
2582 /* if a 'linkonce' section is already present, we
2583 do not add it again. It is a little tricky as
2584 symbols can still be defined in
2586 sm_table
[i
].link_once
= 1;
2593 /* not found: create new section */
2594 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2595 /* take as much info as possible from the section. sh_link and
2596 sh_info will be updated later */
2597 s
->sh_addralign
= sh
->sh_addralign
;
2598 s
->sh_entsize
= sh
->sh_entsize
;
2599 sm_table
[i
].new_section
= 1;
2601 if (sh
->sh_type
!= s
->sh_type
) {
2602 tcc_error_noabort("invalid section type");
2606 /* align start of section */
2607 offset
= s
->data_offset
;
2609 if (0 == strcmp(sh_name
, ".stab")) {
2613 if (0 == strcmp(sh_name
, ".stabstr")) {
2618 size
= sh
->sh_addralign
- 1;
2619 offset
= (offset
+ size
) & ~size
;
2620 if (sh
->sh_addralign
> s
->sh_addralign
)
2621 s
->sh_addralign
= sh
->sh_addralign
;
2622 s
->data_offset
= offset
;
2624 sm_table
[i
].offset
= offset
;
2626 /* concatenate sections */
2628 if (sh
->sh_type
!= SHT_NOBITS
) {
2630 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2631 ptr
= section_ptr_add(s
, size
);
2632 read(fd
, ptr
, size
);
2634 s
->data_offset
+= size
;
2639 /* gr relocate stab strings */
2640 if (stab_index
&& stabstr_index
) {
2643 s
= sm_table
[stab_index
].s
;
2644 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2645 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2646 o
= sm_table
[stabstr_index
].offset
;
2648 a
->n_strx
+= o
, a
++;
2651 /* second short pass to update sh_link and sh_info fields of new
2653 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2655 if (!s
|| !sm_table
[i
].new_section
)
2658 if (sh
->sh_link
> 0)
2659 s
->link
= sm_table
[sh
->sh_link
].s
;
2660 if (sh
->sh_type
== SHT_RELX
) {
2661 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2662 /* update backward link */
2663 s1
->sections
[s
->sh_info
]->reloc
= s
;
2668 /* resolve symbols */
2669 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2672 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2673 if (sym
->st_shndx
!= SHN_UNDEF
&&
2674 sym
->st_shndx
< SHN_LORESERVE
) {
2675 sm
= &sm_table
[sym
->st_shndx
];
2676 if (sm
->link_once
) {
2677 /* if a symbol is in a link once section, we use the
2678 already defined symbol. It is very important to get
2679 correct relocations */
2680 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2681 name
= (char *) strtab
+ sym
->st_name
;
2682 sym_index
= find_elf_sym(symtab_section
, name
);
2684 old_to_new_syms
[i
] = sym_index
;
2688 /* if no corresponding section added, no need to add symbol */
2691 /* convert section number */
2692 sym
->st_shndx
= sm
->s
->sh_num
;
2694 sym
->st_value
+= sm
->offset
;
2697 name
= (char *) strtab
+ sym
->st_name
;
2698 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2699 sym
->st_info
, sym
->st_other
,
2700 sym
->st_shndx
, name
);
2701 old_to_new_syms
[i
] = sym_index
;
2704 /* third pass to patch relocation entries */
2705 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2710 offset
= sm_table
[i
].offset
;
2711 switch(s
->sh_type
) {
2713 /* take relocation offset information */
2714 offseti
= sm_table
[sh
->sh_info
].offset
;
2715 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2718 /* convert symbol index */
2719 type
= ELFW(R_TYPE
)(rel
->r_info
);
2720 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2721 /* NOTE: only one symtab assumed */
2722 if (sym_index
>= nb_syms
)
2724 sym_index
= old_to_new_syms
[sym_index
];
2725 /* ignore link_once in rel section. */
2726 if (!sym_index
&& !sm
->link_once
2727 #ifdef TCC_TARGET_ARM
2728 && type
!= R_ARM_V4BX
2732 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2733 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2736 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2737 /* offset the relocation offset */
2738 rel
->r_offset
+= offseti
;
2739 #ifdef TCC_TARGET_ARM
2740 /* Jumps and branches from a Thumb code to a PLT entry need
2741 special handling since PLT entries are ARM code.
2742 Unconditional bl instructions referencing PLT entries are
2743 handled by converting these instructions into blx
2744 instructions. Other case of instructions referencing a PLT
2745 entry require to add a Thumb stub before the PLT entry to
2746 switch to ARM mode. We set bit plt_thumb_stub of the
2747 attribute of a symbol to indicate such a case. */
2748 if (type
== R_ARM_THM_JUMP24
)
2749 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2762 tcc_free(old_to_new_syms
);
2769 typedef struct ArchiveHeader
{
2770 char ar_name
[16]; /* name of this member */
2771 char ar_date
[12]; /* file mtime */
2772 char ar_uid
[6]; /* owner uid; printed as decimal */
2773 char ar_gid
[6]; /* owner gid; printed as decimal */
2774 char ar_mode
[8]; /* file mode, printed as octal */
2775 char ar_size
[10]; /* file size, printed as decimal */
2776 char ar_fmag
[2]; /* should contain ARFMAG */
2779 static int get_be32(const uint8_t *b
)
2781 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2784 /* load only the objects which resolve undefined symbols */
2785 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2787 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2789 const char *ar_names
, *p
;
2790 const uint8_t *ar_index
;
2793 data
= tcc_malloc(size
);
2794 if (read(fd
, data
, size
) != size
)
2796 nsyms
= get_be32(data
);
2797 ar_index
= data
+ 4;
2798 ar_names
= (char *) ar_index
+ nsyms
* 4;
2802 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2803 sym_index
= find_elf_sym(symtab_section
, p
);
2805 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2806 if(sym
->st_shndx
== SHN_UNDEF
) {
2807 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2809 lseek(fd
, off
, SEEK_SET
);
2810 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2825 /* load a '.a' file */
2826 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2833 unsigned long file_offset
;
2835 /* skip magic which was already checked */
2836 read(fd
, magic
, sizeof(magic
));
2839 len
= read(fd
, &hdr
, sizeof(hdr
));
2842 if (len
!= sizeof(hdr
)) {
2843 tcc_error_noabort("invalid archive");
2846 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2847 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2848 size
= strtol(ar_size
, NULL
, 0);
2849 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2850 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2851 if (ar_name
[i
] != ' ')
2854 ar_name
[i
+ 1] = '\0';
2855 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2857 size
= (size
+ 1) & ~1;
2858 if (!strcmp(ar_name
, "/")) {
2859 /* coff symbol table : we handle it */
2860 if(s1
->alacarte_link
)
2861 return tcc_load_alacarte(s1
, fd
, size
);
2862 } else if (!strcmp(ar_name
, "//") ||
2863 !strcmp(ar_name
, "__.SYMDEF") ||
2864 !strcmp(ar_name
, "__.SYMDEF/") ||
2865 !strcmp(ar_name
, "ARFILENAMES/")) {
2866 /* skip symbol table or archive names */
2868 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2871 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2876 #ifndef TCC_TARGET_PE
2877 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2878 is referenced by the user (so it should be added as DT_NEEDED in
2879 the generated ELF file) */
2880 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2883 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2884 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2885 ElfW(Sym
) *sym
, *dynsym
;
2886 ElfW(Dyn
) *dt
, *dynamic
;
2887 unsigned char *dynstr
;
2888 const char *name
, *soname
;
2889 DLLReference
*dllref
;
2891 read(fd
, &ehdr
, sizeof(ehdr
));
2893 /* test CPU specific stuff */
2894 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2895 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2896 tcc_error_noabort("bad architecture");
2901 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2903 /* load dynamic section and dynamic symbols */
2907 dynsym
= NULL
; /* avoid warning */
2908 dynstr
= NULL
; /* avoid warning */
2909 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2910 switch(sh
->sh_type
) {
2912 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2913 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2916 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2917 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2918 sh1
= &shdr
[sh
->sh_link
];
2919 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2926 /* compute the real library name */
2927 soname
= tcc_basename(filename
);
2929 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2930 if (dt
->d_tag
== DT_SONAME
) {
2931 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2935 /* if the dll is already loaded, do not load it */
2936 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2937 dllref
= s1
->loaded_dlls
[i
];
2938 if (!strcmp(soname
, dllref
->name
)) {
2939 /* but update level if needed */
2940 if (level
< dllref
->level
)
2941 dllref
->level
= level
;
2947 /* add the dll and its level */
2948 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2949 dllref
->level
= level
;
2950 strcpy(dllref
->name
, soname
);
2951 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2953 /* add dynamic symbols in dynsym_section */
2954 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2955 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2956 if (sym_bind
== STB_LOCAL
)
2958 name
= (char *) dynstr
+ sym
->st_name
;
2959 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
2960 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
2963 /* load all referenced DLLs */
2964 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2967 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
2968 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
2969 dllref
= s1
->loaded_dlls
[j
];
2970 if (!strcmp(name
, dllref
->name
))
2971 goto already_loaded
;
2973 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
2974 tcc_error_noabort("referenced dll '%s' not found", name
);
2991 #define LD_TOK_NAME 256
2992 #define LD_TOK_EOF (-1)
2994 /* return next ld script token */
2995 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
3013 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
3014 ch
= file
->buf_ptr
[0];
3022 /* case 'a' ... 'z': */
3049 /* case 'A' ... 'z': */
3084 if (!((ch
>= 'a' && ch
<= 'z') ||
3085 (ch
>= 'A' && ch
<= 'Z') ||
3086 (ch
>= '0' && ch
<= '9') ||
3087 strchr("/.-_+=$:\\,~", ch
)))
3089 if ((q
- name
) < name_size
- 1) {
3108 static int ld_add_file(TCCState
*s1
, const char filename
[])
3112 ret
= tcc_add_file_internal(s1
, filename
, 0);
3114 ret
= tcc_add_dll(s1
, filename
, 0);
3118 static inline int new_undef_syms(void)
3121 ret
= new_undef_sym
;
3126 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3128 char filename
[1024], libname
[1024];
3129 int t
, group
, nblibs
= 0, ret
= 0;
3132 group
= !strcmp(cmd
, "GROUP");
3135 t
= ld_next(s1
, filename
, sizeof(filename
));
3138 t
= ld_next(s1
, filename
, sizeof(filename
));
3141 if (t
== LD_TOK_EOF
) {
3142 tcc_error_noabort("unexpected end of file");
3144 goto lib_parse_error
;
3145 } else if (t
== ')') {
3147 } else if (t
== '-') {
3148 t
= ld_next(s1
, filename
, sizeof(filename
));
3149 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3150 tcc_error_noabort("library name expected");
3152 goto lib_parse_error
;
3154 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3155 if (s1
->static_link
) {
3156 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3158 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3160 } else if (t
!= LD_TOK_NAME
) {
3161 tcc_error_noabort("filename expected");
3163 goto lib_parse_error
;
3165 if (!strcmp(filename
, "AS_NEEDED")) {
3166 ret
= ld_add_file_list(s1
, cmd
, 1);
3168 goto lib_parse_error
;
3170 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3172 ret
= ld_add_file(s1
, filename
);
3174 goto lib_parse_error
;
3176 /* Add the filename *and* the libname to avoid future conversions */
3177 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3178 if (libname
[0] != '\0')
3179 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3183 t
= ld_next(s1
, filename
, sizeof(filename
));
3185 t
= ld_next(s1
, filename
, sizeof(filename
));
3188 if (group
&& !as_needed
) {
3189 while (new_undef_syms()) {
3192 for (i
= 0; i
< nblibs
; i
++)
3193 ld_add_file(s1
, libs
[i
]);
3197 dynarray_reset(&libs
, &nblibs
);
3201 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3203 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3206 char filename
[1024];
3209 ch
= file
->buf_ptr
[0];
3212 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3213 if (t
== LD_TOK_EOF
)
3215 else if (t
!= LD_TOK_NAME
)
3217 if (!strcmp(cmd
, "INPUT") ||
3218 !strcmp(cmd
, "GROUP")) {
3219 ret
= ld_add_file_list(s1
, cmd
, 0);
3222 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3223 !strcmp(cmd
, "TARGET")) {
3224 /* ignore some commands */
3225 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3229 t
= ld_next(s1
, filename
, sizeof(filename
));
3230 if (t
== LD_TOK_EOF
) {
3231 tcc_error_noabort("unexpected end of file");
3233 } else if (t
== ')') {
3243 #endif /* !TCC_TARGET_PE */