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
)
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 if (!find_elf_sym(s1
->dynsym
, name
))
1049 offset
= sym
->st_value
;
1050 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1051 if (need_plt_entry
) {
1056 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1059 /* if we build a DLL, we add a %ebx offset */
1060 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1066 /* add a PLT entry */
1068 if (plt
->data_offset
== 0) {
1069 /* first plt entry */
1070 p
= section_ptr_add(plt
, 16);
1071 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1072 p
[1] = modrm
+ 0x10;
1073 put32(p
+ 2, PTR_SIZE
);
1074 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1076 put32(p
+ 8, PTR_SIZE
* 2);
1079 p
= section_ptr_add(plt
, 16);
1080 p
[0] = 0xff; /* jmp *(got + x) */
1082 put32(p
+ 2, s1
->got
->data_offset
);
1083 p
[6] = 0x68; /* push $xxx */
1084 put32(p
+ 7, (plt
->data_offset
- 32) >> 1);
1085 p
[11] = 0xe9; /* jmp plt_start */
1086 put32(p
+ 12, -(plt
->data_offset
));
1088 /* the symbol is modified so that it will be relocated to
1090 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1091 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1093 offset
= plt
->data_offset
- 16;
1095 #elif defined(TCC_TARGET_ARM)
1096 if (need_plt_entry
) {
1100 /* if we build a DLL, we add a %ebx offset */
1101 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1102 tcc_error("DLLs unimplemented!");
1104 /* add a PLT entry */
1106 if (plt
->data_offset
== 0) {
1107 /* first plt entry */
1108 p
= section_ptr_add(plt
, 16);
1109 put32(p
, 0xe52de004); /* push {lr} */
1110 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1111 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1112 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1115 if (s1
->sym_attrs
[sym_index
].plt_thumb_stub
) {
1116 p
= section_ptr_add(plt
, 20);
1117 put32(p
, 0x4778); /* bx pc */
1118 put32(p
+2, 0x46c0); /* nop */
1121 p
= section_ptr_add(plt
, 16);
1122 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1123 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1124 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1125 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1127 /* the symbol is modified so that it will be relocated to
1129 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1130 offset
= plt
->data_offset
- 16;
1132 #elif defined(TCC_TARGET_C67)
1133 tcc_error("C67 got not implemented");
1135 #error unsupported CPU
1137 index
= put_elf_sym(s1
->dynsym
, offset
,
1138 size
, info
, 0, sym
->st_shndx
, name
);
1139 if (got_entry_present
) {
1140 put_elf_reloc(s1
->dynsym
, s1
->got
,
1141 s1
->sym_attrs
[sym_index
].got_offset
,
1146 /* put a got entry */
1147 put_elf_reloc(s1
->dynsym
, s1
->got
,
1148 s1
->got
->data_offset
,
1151 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1155 /* build GOT and PLT entries */
1156 ST_FUNC
void build_got_entries(TCCState
*s1
)
1161 int i
, type
, reloc_type
, sym_index
;
1163 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1164 s
= s1
->sections
[i
];
1165 if (s
->sh_type
!= SHT_RELX
)
1167 /* no need to handle got relocations */
1168 if (s
->link
!= symtab_section
)
1170 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1171 type
= ELFW(R_TYPE
)(rel
->r_info
);
1173 #if defined(TCC_TARGET_I386)
1180 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1181 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1182 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1183 /* look at the symbol got offset. If none, then add one */
1184 if (type
== R_386_GOT32
)
1185 reloc_type
= R_386_GLOB_DAT
;
1187 reloc_type
= R_386_JMP_SLOT
;
1188 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1192 #elif defined(TCC_TARGET_ARM)
1199 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1200 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1201 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1202 /* look at the symbol got offset. If none, then add one */
1203 if (type
== R_ARM_GOT32
)
1204 reloc_type
= R_ARM_GLOB_DAT
;
1206 reloc_type
= R_ARM_JUMP_SLOT
;
1207 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1211 case R_ARM_THM_JUMP24
:
1212 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1213 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1214 /* We are relocating a jump from thumb code to arm code */
1215 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1218 char *name
, buf
[1024];
1219 Section
*text_section
;
1221 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1222 text_section
= s1
->sections
[sym
->st_shndx
];
1223 /* Modify reloc to target a thumb stub to switch to ARM */
1224 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1225 index
= put_elf_sym(symtab_section
,
1226 text_section
->data_offset
+ 1,
1227 sym
->st_size
, sym
->st_info
, 0,
1228 sym
->st_shndx
, buf
);
1229 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1230 /* Create a thumb stub fonction to switch to ARM mode */
1231 put_elf_reloc(symtab_section
, text_section
,
1232 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1234 p
= section_ptr_add(text_section
, 8);
1235 put32(p
, 0x4778); /* bx pc */
1236 put32(p
+2, 0x46c0); /* nop */
1237 put32(p
+4, 0xeafffffe); /* b $sym */
1239 #elif defined(TCC_TARGET_C67)
1246 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1247 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1248 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1249 /* look at the symbol got offset. If none, then add one */
1250 if (type
== R_C60_GOT32
)
1251 reloc_type
= R_C60_GLOB_DAT
;
1253 reloc_type
= R_C60_JMP_SLOT
;
1254 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1258 #elif defined(TCC_TARGET_X86_64)
1259 case R_X86_64_GOT32
:
1260 case R_X86_64_GOTTPOFF
:
1261 case R_X86_64_GOTPCREL
:
1262 case R_X86_64_PLT32
:
1265 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1266 type
== R_X86_64_PLT32
) {
1267 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1268 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1269 /* look at the symbol got offset. If none, then add one */
1270 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1271 reloc_type
= R_X86_64_GLOB_DAT
;
1273 reloc_type
= R_X86_64_JUMP_SLOT
;
1274 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1279 #error unsupported CPU
1288 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1289 const char *symtab_name
, int sh_type
, int sh_flags
,
1290 const char *strtab_name
,
1291 const char *hash_name
, int hash_sh_flags
)
1293 Section
*symtab
, *strtab
, *hash
;
1294 int *ptr
, nb_buckets
;
1296 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1297 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1298 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1299 put_elf_str(strtab
, "");
1300 symtab
->link
= strtab
;
1301 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1305 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1306 hash
->sh_entsize
= sizeof(int);
1307 symtab
->hash
= hash
;
1308 hash
->link
= symtab
;
1310 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1311 ptr
[0] = nb_buckets
;
1313 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1317 /* put dynamic tag */
1318 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1321 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1323 dyn
->d_un
.d_val
= val
;
1326 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1330 char sym_start
[1024];
1333 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1334 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1336 s
= find_section(s1
, section_name
);
1341 end_offset
= s
->data_offset
;
1344 add_elf_sym(symtab_section
,
1346 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1347 s
->sh_num
, sym_start
);
1348 add_elf_sym(symtab_section
,
1350 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1351 s
->sh_num
, sym_end
);
1354 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1356 #ifdef CONFIG_TCC_BCHECK
1358 Section
*init_section
;
1359 unsigned char *pinit
;
1362 if (0 == s1
->do_bounds_check
)
1365 /* XXX: add an object file to do that */
1366 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1368 add_elf_sym(symtab_section
, 0, 0,
1369 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1370 bounds_section
->sh_num
, "__bounds_start");
1371 #ifdef TCC_TARGET_I386
1372 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1373 /* add 'call __bound_init()' in .init section */
1374 init_section
= find_section(s1
, ".init");
1375 pinit
= section_ptr_add(init_section
, 5);
1377 put32(pinit
+ 1, -4);
1378 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1379 put_elf_reloc(symtab_section
, init_section
,
1380 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1386 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1389 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1390 return tcc_add_file(s1
, buf
);
1393 /* add tcc runtime libraries */
1394 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1397 if (!s1
->nostdlib
) {
1398 tcc_add_library(s1
, "c");
1399 #ifdef CONFIG_USE_LIBGCC
1400 if (!s1
->static_link
) {
1401 tcc_add_file(s1
, TCC_LIBGCC
);
1402 tcc_add_support(s1
, "libtcc1.a");
1404 tcc_add_support(s1
, "libtcc1.a");
1406 tcc_add_support(s1
, "libtcc1.a");
1410 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1411 libtcc1.a must be loaded before for __bound_init to be defined and
1412 crtn.o must be loaded after to not finalize _init too early. */
1415 if (!s1
->nostdlib
) {
1416 /* add crt end if not memory output */
1417 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1418 tcc_add_crt(s1
, "crtn.o");
1422 /* add various standard linker symbols (must be done after the
1423 sections are filled (for example after allocating common
1425 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1431 add_elf_sym(symtab_section
,
1432 text_section
->data_offset
, 0,
1433 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1434 text_section
->sh_num
, "_etext");
1435 add_elf_sym(symtab_section
,
1436 data_section
->data_offset
, 0,
1437 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1438 data_section
->sh_num
, "_edata");
1439 add_elf_sym(symtab_section
,
1440 bss_section
->data_offset
, 0,
1441 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1442 bss_section
->sh_num
, "_end");
1443 /* horrible new standard ldscript defines */
1444 add_init_array_defines(s1
, ".preinit_array");
1445 add_init_array_defines(s1
, ".init_array");
1446 add_init_array_defines(s1
, ".fini_array");
1448 /* add start and stop symbols for sections whose name can be
1450 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1451 s
= s1
->sections
[i
];
1452 if (s
->sh_type
== SHT_PROGBITS
&&
1453 (s
->sh_flags
& SHF_ALLOC
)) {
1457 /* check if section name can be expressed in C */
1463 if (!isid(ch
) && !isnum(ch
))
1467 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1468 add_elf_sym(symtab_section
,
1470 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1472 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1473 add_elf_sym(symtab_section
,
1475 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1482 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1483 const int *sec_order
)
1486 int i
, offset
, size
;
1489 for(i
=1;i
<s1
->nb_sections
;i
++) {
1490 s
= s1
->sections
[sec_order
[i
]];
1491 if (s
->sh_type
!= SHT_NOBITS
&&
1492 (s
->sh_flags
& SHF_ALLOC
)) {
1493 while (offset
< s
->sh_offset
) {
1498 fwrite(s
->data
, 1, size
, f
);
1504 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1506 #define EXTRA_RELITEMS 14
1508 /* move the relocation value from .dynsym to .got */
1509 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1511 uint32_t *gotd
= (void *)s1
->got
->data
;
1514 gotd
+= 3; /* dummy entries in .got */
1515 /* relocate symbols in .dynsym */
1516 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1517 if (sym
->st_shndx
== SHN_UNDEF
) {
1518 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1525 #define EXTRA_RELITEMS 9
1527 /* zero plt offsets of weak symbols in .dynsym */
1528 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1532 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1533 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1538 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1540 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1541 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1542 unsigned long offset
;
1544 if (sym_index
>= s1
->nb_sym_attrs
)
1546 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1547 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1548 #ifdef TCC_TARGET_X86_64
1549 /* only works for x86-64 */
1550 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1552 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1555 /* Perform relocation to GOT or PLTÂ entries */
1556 ST_FUNC
void fill_got(TCCState
*s1
)
1562 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1563 s
= s1
->sections
[i
];
1564 if (s
->sh_type
!= SHT_RELX
)
1566 /* no need to handle got relocations */
1567 if (s
->link
!= symtab_section
)
1569 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1570 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1571 case R_X86_64_GOT32
:
1572 case R_X86_64_GOTPCREL
:
1573 case R_X86_64_PLT32
:
1574 fill_got_entry(s1
, rel
);
1581 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1582 in shared libraries and export non local defined symbols to shared libraries
1583 if -rdynamic switch was given on command line */
1584 static void bind_exe_dynsyms(TCCState
*s1
)
1587 int sym_index
, index
;
1588 ElfW(Sym
) *sym
, *esym
;
1591 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1592 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1593 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1594 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1595 if (sym
->st_shndx
== SHN_UNDEF
) {
1596 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1597 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1599 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1600 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1601 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1602 /* Indirect functions shall have STT_FUNC type in executable
1603 * dynsym section. Indeed, a dlsym call following a lazy
1604 * resolution would pick the symbol value from the
1605 * executable dynsym entry which would contain the address
1606 * of the function wanted by the caller of dlsym instead of
1607 * the address of the function that would return that
1609 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1610 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1611 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1612 } else if (type
== STT_OBJECT
) {
1613 unsigned long offset
;
1615 offset
= bss_section
->data_offset
;
1616 /* XXX: which alignment ? */
1617 offset
= (offset
+ 16 - 1) & -16;
1618 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1619 esym
->st_info
, 0, bss_section
->sh_num
,
1621 /* Ensure R_COPY works for weak symbol aliases */
1622 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1623 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1624 if ((dynsym
->st_value
== esym
->st_value
)
1625 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1626 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1628 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1630 bss_section
->sh_num
, dynname
);
1635 put_elf_reloc(s1
->dynsym
, bss_section
,
1636 offset
, R_COPY
, index
);
1637 offset
+= esym
->st_size
;
1638 bss_section
->data_offset
= offset
;
1641 /* STB_WEAK undefined symbols are accepted */
1642 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1643 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1644 !strcmp(name
, "_fp_hw")) {
1646 tcc_error_noabort("undefined symbol '%s'", name
);
1649 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1650 /* if -rdynamic option, then export all non local symbols */
1651 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1652 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1653 0, sym
->st_shndx
, name
);
1658 /* Bind symbols of libraries: export non local symbols of executable that
1659 resolve undefined symbols of shared libraries */
1660 static void bind_libs_dynsyms(TCCState
*s1
)
1664 ElfW(Sym
) *sym
, *esym
;
1666 /* now look at unresolved dynamic symbols and export
1667 corresponding symbol */
1668 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1669 if (esym
->st_shndx
== SHN_UNDEF
) {
1670 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1671 sym_index
= find_elf_sym(symtab_section
, name
);
1673 /* XXX: avoid adding a symbol if already present because of
1675 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1676 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1677 sym
->st_info
, 0, sym
->st_shndx
, name
);
1679 /* weak symbols can stay undefined */
1680 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1681 tcc_warning("undefined dynamic symbol '%s'", name
);
1687 /* Export all non local symbols (for shared libraries) */
1688 static void export_global_syms(TCCState
*s1
)
1690 int nb_syms
, dynindex
, index
;
1694 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1695 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1696 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1697 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1698 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1699 int type
= ELFW(ST_TYPE
)(sym
->st_info
);
1700 if ((type
== STT_FUNC
|| type
== STT_GNU_IFUNC
)
1701 && sym
->st_shndx
== SHN_UNDEF
) {
1702 int visibility
= ELFW(ST_BIND
)(sym
->st_info
);
1703 put_got_entry(s1
, R_JMP_SLOT
, sym
->st_size
,
1704 ELFW(ST_INFO
)(visibility
, STT_FUNC
),
1705 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1706 } else if (type
== STT_OBJECT
) {
1707 put_got_entry(s1
, R_X86_64_GLOB_DAT
, sym
->st_size
, sym
->st_info
,
1708 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1712 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1713 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1714 sym
->st_info
, 0, sym
->st_shndx
, name
);
1715 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1716 s1
->symtab_to_dynsym
[index
] = dynindex
;
1722 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1723 address for PLT and GOT are known (see fill_program_header) */
1724 static void relocate_plt(TCCState
*s1
)
1729 p_end
= p
+ s1
->plt
->data_offset
;
1731 #if defined(TCC_TARGET_I386)
1732 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1733 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1736 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1739 #elif defined(TCC_TARGET_X86_64)
1740 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1741 put32(p
+ 2, get32(p
+ 2) + x
);
1742 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1745 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1748 #elif defined(TCC_TARGET_ARM)
1750 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1753 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1755 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1758 #elif defined(TCC_TARGET_C67)
1761 #error unsupported CPU
1766 /* Allocate strings for section names and decide if an unallocated section
1769 NOTE: the strsec section comes last, so its size is also correct ! */
1770 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1775 /* Allocate strings for section names */
1776 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1777 s
= s1
->sections
[i
];
1778 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1779 /* when generating a DLL, we include relocations but we may
1781 if (file_type
== TCC_OUTPUT_DLL
&&
1782 s
->sh_type
== SHT_RELX
&&
1783 !(s
->sh_flags
& SHF_ALLOC
)) {
1784 /* gr: avoid bogus relocs for empty (debug) sections */
1785 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1786 prepare_dynamic_rel(s1
, s
);
1787 else if (s1
->do_debug
)
1788 s
->sh_size
= s
->data_offset
;
1789 } else if (s1
->do_debug
||
1790 file_type
== TCC_OUTPUT_OBJ
||
1791 (s
->sh_flags
& SHF_ALLOC
) ||
1792 i
== (s1
->nb_sections
- 1)) {
1793 /* we output all sections if debug or object file */
1794 s
->sh_size
= s
->data_offset
;
1799 /* Info to be copied in dynamic section */
1803 unsigned long dyn_rel_off
;
1806 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1812 /* Assign sections to segments and decide how are sections laid out when loaded
1813 in memory. This function also fills corresponding program headers. */
1814 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1815 Section
*interp
, struct dyn_inf
*dyninf
,
1818 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1824 file_type
= s1
->output_type
;
1826 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1827 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1832 if (s1
->has_text_addr
) {
1833 int a_offset
, p_offset
;
1834 addr
= s1
->text_addr
;
1835 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1837 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1838 p_offset
= file_offset
& (s1
->section_align
- 1);
1839 if (a_offset
< p_offset
)
1840 a_offset
+= s1
->section_align
;
1841 file_offset
+= (a_offset
- p_offset
);
1843 if (file_type
== TCC_OUTPUT_DLL
)
1846 addr
= ELF_START_ADDR
;
1847 /* compute address after headers */
1848 addr
+= (file_offset
& (s1
->section_align
- 1));
1852 /* Leave one program headers for the program interpreter and one for
1853 the program header table itself if needed. These are done later as
1854 they require section layout to be done first. */
1856 ph
+= 1 + HAVE_PHDR
;
1858 /* dynamic relocation table information, for .dynamic section */
1859 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1860 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1861 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1864 for(j
= 0; j
< 2; j
++) {
1865 ph
->p_type
= PT_LOAD
;
1867 ph
->p_flags
= PF_R
| PF_X
;
1869 ph
->p_flags
= PF_R
| PF_W
;
1870 ph
->p_align
= s1
->section_align
;
1872 /* Decide the layout of sections loaded in memory. This must
1873 be done before program headers are filled since they contain
1874 info about the layout. We do the following ordering: interp,
1875 symbol tables, relocations, progbits, nobits */
1876 /* XXX: do faster and simpler sorting */
1877 for(k
= 0; k
< 5; k
++) {
1878 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1879 s
= s1
->sections
[i
];
1880 /* compute if section should be included */
1882 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1886 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1887 (SHF_ALLOC
| SHF_WRITE
))
1893 } else if (s
->sh_type
== SHT_DYNSYM
||
1894 s
->sh_type
== SHT_STRTAB
||
1895 s
->sh_type
== SHT_HASH
) {
1898 } else if (s
->sh_type
== SHT_RELX
) {
1901 } else if (s
->sh_type
== SHT_NOBITS
) {
1908 sec_order
[sh_order_index
++] = i
;
1910 /* section matches: we align it and add its size */
1912 addr
= (addr
+ s
->sh_addralign
- 1) &
1913 ~(s
->sh_addralign
- 1);
1914 file_offset
+= (int) ( addr
- tmp
);
1915 s
->sh_offset
= file_offset
;
1918 /* update program header infos */
1919 if (ph
->p_offset
== 0) {
1920 ph
->p_offset
= file_offset
;
1922 ph
->p_paddr
= ph
->p_vaddr
;
1924 /* update dynamic relocation infos */
1925 if (s
->sh_type
== SHT_RELX
) {
1926 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1927 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1928 dyninf
->rel_addr
= addr
;
1929 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1931 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1932 dyninf
->bss_addr
= addr
;
1933 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1936 if (dyninf
->rel_size
== 0)
1937 dyninf
->rel_addr
= addr
;
1938 dyninf
->rel_size
+= s
->sh_size
;
1942 if (s
->sh_type
!= SHT_NOBITS
)
1943 file_offset
+= s
->sh_size
;
1946 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1947 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1950 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1951 /* if in the middle of a page, we duplicate the page in
1952 memory so that one copy is RX and the other is RW */
1953 if ((addr
& (s1
->section_align
- 1)) != 0)
1954 addr
+= s1
->section_align
;
1956 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1957 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1958 ~(s1
->section_align
- 1);
1964 /* all other sections come after */
1965 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1966 s
= s1
->sections
[i
];
1967 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
1969 sec_order
[sh_order_index
++] = i
;
1971 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
1972 ~(s
->sh_addralign
- 1);
1973 s
->sh_offset
= file_offset
;
1974 if (s
->sh_type
!= SHT_NOBITS
)
1975 file_offset
+= s
->sh_size
;
1981 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
1986 /* if interpreter, then add corresponding program header */
1992 int len
= phnum
* sizeof(ElfW(Phdr
));
1994 ph
->p_type
= PT_PHDR
;
1995 ph
->p_offset
= sizeof(ElfW(Ehdr
));
1996 ph
->p_vaddr
= interp
->sh_addr
- len
;
1997 ph
->p_paddr
= ph
->p_vaddr
;
1998 ph
->p_filesz
= ph
->p_memsz
= len
;
1999 ph
->p_flags
= PF_R
| PF_X
;
2000 ph
->p_align
= 4; /* interp->sh_addralign; */
2004 ph
->p_type
= PT_INTERP
;
2005 ph
->p_offset
= interp
->sh_offset
;
2006 ph
->p_vaddr
= interp
->sh_addr
;
2007 ph
->p_paddr
= ph
->p_vaddr
;
2008 ph
->p_filesz
= interp
->sh_size
;
2009 ph
->p_memsz
= interp
->sh_size
;
2011 ph
->p_align
= interp
->sh_addralign
;
2014 /* if dynamic section, then add corresponding program header */
2016 ph
= &phdr
[phnum
- 1];
2018 ph
->p_type
= PT_DYNAMIC
;
2019 ph
->p_offset
= dynamic
->sh_offset
;
2020 ph
->p_vaddr
= dynamic
->sh_addr
;
2021 ph
->p_paddr
= ph
->p_vaddr
;
2022 ph
->p_filesz
= dynamic
->sh_size
;
2023 ph
->p_memsz
= dynamic
->sh_size
;
2024 ph
->p_flags
= PF_R
| PF_W
;
2025 ph
->p_align
= dynamic
->sh_addralign
;
2029 /* Fill the dynamic section with tags describing the address and size of
2031 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2035 dynamic
= dyninf
->dynamic
;
2037 /* put dynamic section entries */
2038 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2039 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2040 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2041 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2042 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2043 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2044 #ifdef TCC_TARGET_X86_64
2045 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2046 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2047 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2049 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2050 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2051 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2052 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2053 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2054 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2055 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2057 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2058 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2059 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2063 put_dt(dynamic
, DT_DEBUG
, 0);
2064 put_dt(dynamic
, DT_NULL
, 0);
2067 /* Relocate remaining sections and symbols (that is those not related to
2069 static int final_sections_reloc(TCCState
*s1
)
2074 relocate_syms(s1
, 0);
2076 if (s1
->nb_errors
!= 0)
2079 /* relocate sections */
2080 /* XXX: ignore sections with allocated relocations ? */
2081 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2082 s
= s1
->sections
[i
];
2083 if (s
->reloc
&& s
!= s1
->got
)
2084 relocate_section(s1
, s
);
2087 /* relocate relocation entries if the relocation tables are
2088 allocated in the executable */
2089 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2090 s
= s1
->sections
[i
];
2091 if ((s
->sh_flags
& SHF_ALLOC
) &&
2092 s
->sh_type
== SHT_RELX
) {
2093 relocate_rel(s1
, s
);
2099 /* Create an ELF file on disk.
2100 This function handle ELF specific layout requirements */
2101 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2102 int file_offset
, int *sec_order
)
2104 int i
, shnum
, offset
, size
, file_type
;
2107 ElfW(Shdr
) shdr
, *sh
;
2109 file_type
= s1
->output_type
;
2110 shnum
= s1
->nb_sections
;
2112 memset(&ehdr
, 0, sizeof(ehdr
));
2115 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2116 ehdr
.e_phnum
= phnum
;
2117 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2121 file_offset
= (file_offset
+ 3) & -4;
2124 ehdr
.e_ident
[0] = ELFMAG0
;
2125 ehdr
.e_ident
[1] = ELFMAG1
;
2126 ehdr
.e_ident
[2] = ELFMAG2
;
2127 ehdr
.e_ident
[3] = ELFMAG3
;
2128 ehdr
.e_ident
[4] = ELFCLASSW
;
2129 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2130 ehdr
.e_ident
[6] = EV_CURRENT
;
2131 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2132 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2134 #ifdef TCC_TARGET_ARM
2136 ehdr
.e_ident
[EI_OSABI
] = 0;
2137 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2138 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2139 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2140 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2141 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2143 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2145 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2150 case TCC_OUTPUT_EXE
:
2151 ehdr
.e_type
= ET_EXEC
;
2152 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2154 case TCC_OUTPUT_DLL
:
2155 ehdr
.e_type
= ET_DYN
;
2156 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2158 case TCC_OUTPUT_OBJ
:
2159 ehdr
.e_type
= ET_REL
;
2162 ehdr
.e_machine
= EM_TCC_TARGET
;
2163 ehdr
.e_version
= EV_CURRENT
;
2164 ehdr
.e_shoff
= file_offset
;
2165 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2166 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2167 ehdr
.e_shnum
= shnum
;
2168 ehdr
.e_shstrndx
= shnum
- 1;
2170 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2171 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2172 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2174 sort_syms(s1
, symtab_section
);
2175 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2176 s
= s1
->sections
[sec_order
[i
]];
2177 if (s
->sh_type
!= SHT_NOBITS
) {
2178 if (s
->sh_type
== SHT_DYNSYM
)
2179 patch_dynsym_undef(s1
, s
);
2180 while (offset
< s
->sh_offset
) {
2185 fwrite(s
->data
, 1, size
, f
);
2190 /* output section headers */
2191 while (offset
< ehdr
.e_shoff
) {
2196 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2198 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2199 s
= s1
->sections
[i
];
2201 sh
->sh_name
= s
->sh_name
;
2202 sh
->sh_type
= s
->sh_type
;
2203 sh
->sh_flags
= s
->sh_flags
;
2204 sh
->sh_entsize
= s
->sh_entsize
;
2205 sh
->sh_info
= s
->sh_info
;
2207 sh
->sh_link
= s
->link
->sh_num
;
2208 sh
->sh_addralign
= s
->sh_addralign
;
2209 sh
->sh_addr
= s
->sh_addr
;
2210 sh
->sh_offset
= s
->sh_offset
;
2211 sh
->sh_size
= s
->sh_size
;
2213 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2217 /* Write an elf, coff or "binary" file */
2218 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2219 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2221 int fd
, mode
, file_type
;
2224 file_type
= s1
->output_type
;
2225 if (file_type
== TCC_OUTPUT_OBJ
)
2230 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2232 tcc_error_noabort("could not write '%s'", filename
);
2235 f
= fdopen(fd
, "wb");
2237 printf("<- %s\n", filename
);
2239 #ifdef TCC_TARGET_COFF
2240 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2241 tcc_output_coff(s1
, f
);
2244 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2245 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2247 tcc_output_binary(s1
, f
, sec_order
);
2253 /* Output an elf, coff or binary file */
2254 /* XXX: suppress unneeded sections */
2255 static int elf_output_file(TCCState
*s1
, const char *filename
)
2257 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2258 struct dyn_inf dyninf
;
2261 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2263 file_type
= s1
->output_type
;
2266 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2267 if (file_type
!= TCC_OUTPUT_OBJ
) {
2268 tcc_add_runtime(s1
);
2273 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2274 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2276 if (file_type
!= TCC_OUTPUT_OBJ
) {
2277 relocate_common_syms();
2279 tcc_add_linker_symbols(s1
);
2281 if (!s1
->static_link
) {
2282 if (file_type
== TCC_OUTPUT_EXE
) {
2284 /* allow override the dynamic loader */
2285 const char *elfint
= getenv("LD_SO");
2287 elfint
= DEFAULT_ELFINTERP(s1
);
2288 /* add interpreter section only if executable */
2289 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2290 interp
->sh_addralign
= 1;
2291 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2292 strcpy(ptr
, elfint
);
2295 /* add dynamic symbol table */
2296 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2298 ".hash", SHF_ALLOC
);
2299 dynstr
= s1
->dynsym
->link
;
2301 /* add dynamic section */
2302 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2303 SHF_ALLOC
| SHF_WRITE
);
2304 dynamic
->link
= dynstr
;
2305 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2308 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2309 SHF_ALLOC
| SHF_EXECINSTR
);
2310 s1
->plt
->sh_entsize
= 4;
2314 if (file_type
== TCC_OUTPUT_EXE
) {
2315 bind_exe_dynsyms(s1
);
2317 if (s1
->nb_errors
) {
2322 bind_libs_dynsyms(s1
);
2323 } else /* shared library case: simply export all global symbols */
2324 export_global_syms(s1
);
2326 build_got_entries(s1
);
2328 /* add a list of needed dlls */
2329 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2330 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2331 if (dllref
->level
== 0)
2332 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2336 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2338 /* XXX: currently, since we do not handle PIC code, we
2339 must relocate the readonly segments */
2340 if (file_type
== TCC_OUTPUT_DLL
) {
2342 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2343 put_dt(dynamic
, DT_TEXTREL
, 0);
2347 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2349 /* add necessary space for other entries */
2350 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2351 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2353 /* still need to build got entries in case of static link */
2354 build_got_entries(s1
);
2358 /* we add a section for symbols */
2359 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2360 put_elf_str(strsec
, "");
2362 /* compute number of sections */
2363 shnum
= s1
->nb_sections
;
2365 /* this array is used to reorder sections in the output file */
2366 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2369 /* compute number of program headers */
2372 case TCC_OUTPUT_OBJ
:
2375 case TCC_OUTPUT_EXE
:
2376 if (!s1
->static_link
)
2377 phnum
= 4 + HAVE_PHDR
;
2381 case TCC_OUTPUT_DLL
:
2386 /* Allocate strings for section names */
2387 alloc_sec_names(s1
, file_type
, strsec
);
2389 /* allocate program segment headers */
2390 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2392 /* compute section to program header mapping */
2393 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2395 /* Fill remaining program header and finalize relocation related to dynamic
2398 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2400 dyninf
.dynamic
= dynamic
;
2401 dyninf
.dynstr
= dynstr
;
2403 fill_dynamic(s1
, &dyninf
);
2405 /* put in GOT the dynamic section address and relocate PLT */
2406 put32(s1
->got
->data
, dynamic
->sh_addr
);
2407 if (file_type
== TCC_OUTPUT_EXE
2408 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2409 || file_type
== TCC_OUTPUT_DLL
2414 /* relocate symbols in .dynsym now that final addresses are known */
2415 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2416 /* relocate to PLT if symbol corresponds to a PLT entry */
2417 if (sym
->st_shndx
== SHN_UNDEF
) {
2419 sym
->st_value
+= s1
->plt
->sh_addr
;
2420 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2421 /* do symbol relocation */
2422 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2428 /* if building executable or DLL, then relocate each section
2429 except the GOT which is already relocated */
2430 if (file_type
!= TCC_OUTPUT_OBJ
) {
2431 ret
= final_sections_reloc(s1
);
2436 /* Perform relocation to GOT or PLTÂ entries */
2437 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2440 /* Create the ELF file with name 'filename' */
2441 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2443 tcc_free(s1
->symtab_to_dynsym
);
2444 tcc_free(sec_order
);
2446 tcc_free(s1
->sym_attrs
);
2450 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2453 #ifdef TCC_TARGET_PE
2454 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2455 ret
= pe_output_file(s
, filename
);
2458 ret
= elf_output_file(s
, filename
);
2462 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2466 data
= tcc_malloc(size
);
2467 lseek(fd
, file_offset
, SEEK_SET
);
2468 read(fd
, data
, size
);
2472 typedef struct SectionMergeInfo
{
2473 Section
*s
; /* corresponding existing section */
2474 unsigned long offset
; /* offset of the new section in the existing section */
2475 uint8_t new_section
; /* true if section 's' was added */
2476 uint8_t link_once
; /* true if link once section */
2479 /* load an object file and merge it with current files */
2480 /* XXX: handle correctly stab (debug) info */
2481 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2482 int fd
, unsigned long file_offset
)
2485 ElfW(Shdr
) *shdr
, *sh
;
2486 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2487 unsigned char *strsec
, *strtab
;
2488 int *old_to_new_syms
;
2489 char *sh_name
, *name
;
2490 SectionMergeInfo
*sm_table
, *sm
;
2491 ElfW(Sym
) *sym
, *symtab
;
2498 stab_index
= stabstr_index
= 0;
2500 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2502 if (ehdr
.e_ident
[0] != ELFMAG0
||
2503 ehdr
.e_ident
[1] != ELFMAG1
||
2504 ehdr
.e_ident
[2] != ELFMAG2
||
2505 ehdr
.e_ident
[3] != ELFMAG3
)
2507 /* test if object file */
2508 if (ehdr
.e_type
!= ET_REL
)
2510 /* test CPU specific stuff */
2511 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2512 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2514 tcc_error_noabort("invalid object file");
2518 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2519 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2520 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2522 /* load section names */
2523 sh
= &shdr
[ehdr
.e_shstrndx
];
2524 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2526 /* load symtab and strtab */
2527 old_to_new_syms
= NULL
;
2531 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2533 if (sh
->sh_type
== SHT_SYMTAB
) {
2535 tcc_error_noabort("object must contain only one symtab");
2540 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2541 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2542 sm_table
[i
].s
= symtab_section
;
2544 /* now load strtab */
2545 sh
= &shdr
[sh
->sh_link
];
2546 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2550 /* now examine each section and try to merge its content with the
2552 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2553 /* no need to examine section name strtab */
2554 if (i
== ehdr
.e_shstrndx
)
2557 sh_name
= (char *) strsec
+ sh
->sh_name
;
2558 /* ignore sections types we do not handle */
2559 if (sh
->sh_type
!= SHT_PROGBITS
&&
2560 sh
->sh_type
!= SHT_RELX
&&
2562 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2564 sh
->sh_type
!= SHT_NOBITS
&&
2565 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2566 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2567 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2568 strcmp(sh_name
, ".stabstr")
2571 if (sh
->sh_addralign
< 1)
2572 sh
->sh_addralign
= 1;
2573 /* find corresponding section, if any */
2574 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2575 s
= s1
->sections
[j
];
2576 if (!strcmp(s
->name
, sh_name
)) {
2577 if (!strncmp(sh_name
, ".gnu.linkonce",
2578 sizeof(".gnu.linkonce") - 1)) {
2579 /* if a 'linkonce' section is already present, we
2580 do not add it again. It is a little tricky as
2581 symbols can still be defined in
2583 sm_table
[i
].link_once
= 1;
2590 /* not found: create new section */
2591 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2592 /* take as much info as possible from the section. sh_link and
2593 sh_info will be updated later */
2594 s
->sh_addralign
= sh
->sh_addralign
;
2595 s
->sh_entsize
= sh
->sh_entsize
;
2596 sm_table
[i
].new_section
= 1;
2598 if (sh
->sh_type
!= s
->sh_type
) {
2599 tcc_error_noabort("invalid section type");
2603 /* align start of section */
2604 offset
= s
->data_offset
;
2606 if (0 == strcmp(sh_name
, ".stab")) {
2610 if (0 == strcmp(sh_name
, ".stabstr")) {
2615 size
= sh
->sh_addralign
- 1;
2616 offset
= (offset
+ size
) & ~size
;
2617 if (sh
->sh_addralign
> s
->sh_addralign
)
2618 s
->sh_addralign
= sh
->sh_addralign
;
2619 s
->data_offset
= offset
;
2621 sm_table
[i
].offset
= offset
;
2623 /* concatenate sections */
2625 if (sh
->sh_type
!= SHT_NOBITS
) {
2627 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2628 ptr
= section_ptr_add(s
, size
);
2629 read(fd
, ptr
, size
);
2631 s
->data_offset
+= size
;
2636 /* gr relocate stab strings */
2637 if (stab_index
&& stabstr_index
) {
2640 s
= sm_table
[stab_index
].s
;
2641 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2642 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2643 o
= sm_table
[stabstr_index
].offset
;
2645 a
->n_strx
+= o
, a
++;
2648 /* second short pass to update sh_link and sh_info fields of new
2650 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2652 if (!s
|| !sm_table
[i
].new_section
)
2655 if (sh
->sh_link
> 0)
2656 s
->link
= sm_table
[sh
->sh_link
].s
;
2657 if (sh
->sh_type
== SHT_RELX
) {
2658 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2659 /* update backward link */
2660 s1
->sections
[s
->sh_info
]->reloc
= s
;
2665 /* resolve symbols */
2666 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2669 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2670 if (sym
->st_shndx
!= SHN_UNDEF
&&
2671 sym
->st_shndx
< SHN_LORESERVE
) {
2672 sm
= &sm_table
[sym
->st_shndx
];
2673 if (sm
->link_once
) {
2674 /* if a symbol is in a link once section, we use the
2675 already defined symbol. It is very important to get
2676 correct relocations */
2677 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2678 name
= (char *) strtab
+ sym
->st_name
;
2679 sym_index
= find_elf_sym(symtab_section
, name
);
2681 old_to_new_syms
[i
] = sym_index
;
2685 /* if no corresponding section added, no need to add symbol */
2688 /* convert section number */
2689 sym
->st_shndx
= sm
->s
->sh_num
;
2691 sym
->st_value
+= sm
->offset
;
2694 name
= (char *) strtab
+ sym
->st_name
;
2695 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2696 sym
->st_info
, sym
->st_other
,
2697 sym
->st_shndx
, name
);
2698 old_to_new_syms
[i
] = sym_index
;
2701 /* third pass to patch relocation entries */
2702 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2707 offset
= sm_table
[i
].offset
;
2708 switch(s
->sh_type
) {
2710 /* take relocation offset information */
2711 offseti
= sm_table
[sh
->sh_info
].offset
;
2712 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2715 /* convert symbol index */
2716 type
= ELFW(R_TYPE
)(rel
->r_info
);
2717 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2718 /* NOTE: only one symtab assumed */
2719 if (sym_index
>= nb_syms
)
2721 sym_index
= old_to_new_syms
[sym_index
];
2722 /* ignore link_once in rel section. */
2723 if (!sym_index
&& !sm
->link_once
2724 #ifdef TCC_TARGET_ARM
2725 && type
!= R_ARM_V4BX
2729 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2730 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2733 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2734 /* offset the relocation offset */
2735 rel
->r_offset
+= offseti
;
2736 #ifdef TCC_TARGET_ARM
2737 /* Jumps and branches from a Thumb code to a PLT entry need
2738 special handling since PLT entries are ARM code.
2739 Unconditional bl instructions referencing PLT entries are
2740 handled by converting these instructions into blx
2741 instructions. Other case of instructions referencing a PLT
2742 entry require to add a Thumb stub before the PLT entry to
2743 switch to ARM mode. We set bit plt_thumb_stub of the
2744 attribute of a symbol to indicate such a case. */
2745 if (type
== R_ARM_THM_JUMP24
)
2746 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2759 tcc_free(old_to_new_syms
);
2766 typedef struct ArchiveHeader
{
2767 char ar_name
[16]; /* name of this member */
2768 char ar_date
[12]; /* file mtime */
2769 char ar_uid
[6]; /* owner uid; printed as decimal */
2770 char ar_gid
[6]; /* owner gid; printed as decimal */
2771 char ar_mode
[8]; /* file mode, printed as octal */
2772 char ar_size
[10]; /* file size, printed as decimal */
2773 char ar_fmag
[2]; /* should contain ARFMAG */
2776 static int get_be32(const uint8_t *b
)
2778 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2781 /* load only the objects which resolve undefined symbols */
2782 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2784 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2786 const char *ar_names
, *p
;
2787 const uint8_t *ar_index
;
2790 data
= tcc_malloc(size
);
2791 if (read(fd
, data
, size
) != size
)
2793 nsyms
= get_be32(data
);
2794 ar_index
= data
+ 4;
2795 ar_names
= (char *) ar_index
+ nsyms
* 4;
2799 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2800 sym_index
= find_elf_sym(symtab_section
, p
);
2802 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2803 if(sym
->st_shndx
== SHN_UNDEF
) {
2804 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2806 lseek(fd
, off
, SEEK_SET
);
2807 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2822 /* load a '.a' file */
2823 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2830 unsigned long file_offset
;
2832 /* skip magic which was already checked */
2833 read(fd
, magic
, sizeof(magic
));
2836 len
= read(fd
, &hdr
, sizeof(hdr
));
2839 if (len
!= sizeof(hdr
)) {
2840 tcc_error_noabort("invalid archive");
2843 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2844 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2845 size
= strtol(ar_size
, NULL
, 0);
2846 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2847 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2848 if (ar_name
[i
] != ' ')
2851 ar_name
[i
+ 1] = '\0';
2852 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2854 size
= (size
+ 1) & ~1;
2855 if (!strcmp(ar_name
, "/")) {
2856 /* coff symbol table : we handle it */
2857 if(s1
->alacarte_link
)
2858 return tcc_load_alacarte(s1
, fd
, size
);
2859 } else if (!strcmp(ar_name
, "//") ||
2860 !strcmp(ar_name
, "__.SYMDEF") ||
2861 !strcmp(ar_name
, "__.SYMDEF/") ||
2862 !strcmp(ar_name
, "ARFILENAMES/")) {
2863 /* skip symbol table or archive names */
2865 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2868 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2873 #ifndef TCC_TARGET_PE
2874 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2875 is referenced by the user (so it should be added as DT_NEEDED in
2876 the generated ELF file) */
2877 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2880 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2881 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2882 ElfW(Sym
) *sym
, *dynsym
;
2883 ElfW(Dyn
) *dt
, *dynamic
;
2884 unsigned char *dynstr
;
2885 const char *name
, *soname
;
2886 DLLReference
*dllref
;
2888 read(fd
, &ehdr
, sizeof(ehdr
));
2890 /* test CPU specific stuff */
2891 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2892 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2893 tcc_error_noabort("bad architecture");
2898 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2900 /* load dynamic section and dynamic symbols */
2904 dynsym
= NULL
; /* avoid warning */
2905 dynstr
= NULL
; /* avoid warning */
2906 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2907 switch(sh
->sh_type
) {
2909 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2910 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2913 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2914 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2915 sh1
= &shdr
[sh
->sh_link
];
2916 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2923 /* compute the real library name */
2924 soname
= tcc_basename(filename
);
2926 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2927 if (dt
->d_tag
== DT_SONAME
) {
2928 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2932 /* if the dll is already loaded, do not load it */
2933 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2934 dllref
= s1
->loaded_dlls
[i
];
2935 if (!strcmp(soname
, dllref
->name
)) {
2936 /* but update level if needed */
2937 if (level
< dllref
->level
)
2938 dllref
->level
= level
;
2944 /* add the dll and its level */
2945 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2946 dllref
->level
= level
;
2947 strcpy(dllref
->name
, soname
);
2948 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2950 /* add dynamic symbols in dynsym_section */
2951 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2952 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2953 if (sym_bind
== STB_LOCAL
)
2955 name
= (char *) dynstr
+ sym
->st_name
;
2956 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
2957 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
2960 /* load all referenced DLLs */
2961 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2964 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
2965 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
2966 dllref
= s1
->loaded_dlls
[j
];
2967 if (!strcmp(name
, dllref
->name
))
2968 goto already_loaded
;
2970 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
2971 tcc_error_noabort("referenced dll '%s' not found", name
);
2988 #define LD_TOK_NAME 256
2989 #define LD_TOK_EOF (-1)
2991 /* return next ld script token */
2992 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
3010 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
3011 ch
= file
->buf_ptr
[0];
3019 /* case 'a' ... 'z': */
3046 /* case 'A' ... 'z': */
3081 if (!((ch
>= 'a' && ch
<= 'z') ||
3082 (ch
>= 'A' && ch
<= 'Z') ||
3083 (ch
>= '0' && ch
<= '9') ||
3084 strchr("/.-_+=$:\\,~", ch
)))
3086 if ((q
- name
) < name_size
- 1) {
3105 static int ld_add_file(TCCState
*s1
, const char filename
[])
3109 ret
= tcc_add_file_internal(s1
, filename
, 0);
3111 ret
= tcc_add_dll(s1
, filename
, 0);
3115 static inline int new_undef_syms(void)
3118 ret
= new_undef_sym
;
3123 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3125 char filename
[1024], libname
[1024];
3126 int t
, group
, nblibs
= 0, ret
= 0;
3129 group
= !strcmp(cmd
, "GROUP");
3132 t
= ld_next(s1
, filename
, sizeof(filename
));
3135 t
= ld_next(s1
, filename
, sizeof(filename
));
3138 if (t
== LD_TOK_EOF
) {
3139 tcc_error_noabort("unexpected end of file");
3141 goto lib_parse_error
;
3142 } else if (t
== ')') {
3144 } else if (t
== '-') {
3145 t
= ld_next(s1
, filename
, sizeof(filename
));
3146 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3147 tcc_error_noabort("library name expected");
3149 goto lib_parse_error
;
3151 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3152 if (s1
->static_link
) {
3153 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3155 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3157 } else if (t
!= LD_TOK_NAME
) {
3158 tcc_error_noabort("filename expected");
3160 goto lib_parse_error
;
3162 if (!strcmp(filename
, "AS_NEEDED")) {
3163 ret
= ld_add_file_list(s1
, cmd
, 1);
3165 goto lib_parse_error
;
3167 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3169 ret
= ld_add_file(s1
, filename
);
3171 goto lib_parse_error
;
3173 /* Add the filename *and* the libname to avoid future conversions */
3174 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3175 if (libname
[0] != '\0')
3176 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3180 t
= ld_next(s1
, filename
, sizeof(filename
));
3182 t
= ld_next(s1
, filename
, sizeof(filename
));
3185 if (group
&& !as_needed
) {
3186 while (new_undef_syms()) {
3189 for (i
= 0; i
< nblibs
; i
++)
3190 ld_add_file(s1
, libs
[i
]);
3194 dynarray_reset(&libs
, &nblibs
);
3198 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3200 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3203 char filename
[1024];
3206 ch
= file
->buf_ptr
[0];
3209 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3210 if (t
== LD_TOK_EOF
)
3212 else if (t
!= LD_TOK_NAME
)
3214 if (!strcmp(cmd
, "INPUT") ||
3215 !strcmp(cmd
, "GROUP")) {
3216 ret
= ld_add_file_list(s1
, cmd
, 0);
3219 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3220 !strcmp(cmd
, "TARGET")) {
3221 /* ignore some commands */
3222 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3226 t
= ld_next(s1
, filename
, sizeof(filename
));
3227 if (t
== LD_TOK_EOF
) {
3228 tcc_error_noabort("unexpected end of file");
3230 } else if (t
== ')') {
3240 #endif /* !TCC_TARGET_PE */