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 (s1
->sym_attrs
[sym_index
].has_plt_entry
)
1047 s1
->sym_attrs
[sym_index
].has_plt_entry
= 1;
1048 offset
= sym
->st_value
;
1049 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1050 if (need_plt_entry
) {
1055 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1058 /* if we build a DLL, we add a %ebx offset */
1059 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1065 /* add a PLT entry */
1067 if (plt
->data_offset
== 0) {
1068 /* first plt entry */
1069 p
= section_ptr_add(plt
, 16);
1070 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1071 p
[1] = modrm
+ 0x10;
1072 put32(p
+ 2, PTR_SIZE
);
1073 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1075 put32(p
+ 8, PTR_SIZE
* 2);
1078 p
= section_ptr_add(plt
, 16);
1079 p
[0] = 0xff; /* jmp *(got + x) */
1081 put32(p
+ 2, s1
->got
->data_offset
);
1082 p
[6] = 0x68; /* push $xxx */
1083 put32(p
+ 7, (plt
->data_offset
- 32) >> 1);
1084 p
[11] = 0xe9; /* jmp plt_start */
1085 put32(p
+ 12, -(plt
->data_offset
));
1087 /* the symbol is modified so that it will be relocated to
1089 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1090 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1092 offset
= plt
->data_offset
- 16;
1094 #elif defined(TCC_TARGET_ARM)
1095 if (need_plt_entry
) {
1099 /* if we build a DLL, we add a %ebx offset */
1100 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1101 tcc_error("DLLs unimplemented!");
1103 /* add a PLT entry */
1105 if (plt
->data_offset
== 0) {
1106 /* first plt entry */
1107 p
= section_ptr_add(plt
, 16);
1108 put32(p
, 0xe52de004); /* push {lr} */
1109 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1110 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1111 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1114 if (s1
->sym_attrs
[sym_index
].plt_thumb_stub
) {
1115 p
= section_ptr_add(plt
, 20);
1116 put32(p
, 0x4778); /* bx pc */
1117 put32(p
+2, 0x46c0); /* nop */
1120 p
= section_ptr_add(plt
, 16);
1121 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1122 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1123 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1124 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1126 /* the symbol is modified so that it will be relocated to
1128 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1129 offset
= plt
->data_offset
- 16;
1131 #elif defined(TCC_TARGET_C67)
1132 tcc_error("C67 got not implemented");
1134 #error unsupported CPU
1136 index
= put_elf_sym(s1
->dynsym
, offset
,
1137 size
, info
, 0, sym
->st_shndx
, name
);
1138 if (got_entry_present
) {
1139 put_elf_reloc(s1
->dynsym
, s1
->got
,
1140 s1
->sym_attrs
[sym_index
].got_offset
,
1145 /* put a got entry */
1146 put_elf_reloc(s1
->dynsym
, s1
->got
,
1147 s1
->got
->data_offset
,
1150 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1154 /* build GOT and PLT entries */
1155 ST_FUNC
void build_got_entries(TCCState
*s1
)
1160 int i
, type
, reloc_type
, sym_index
;
1162 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1163 s
= s1
->sections
[i
];
1164 if (s
->sh_type
!= SHT_RELX
)
1166 /* no need to handle got relocations */
1167 if (s
->link
!= symtab_section
)
1169 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1170 type
= ELFW(R_TYPE
)(rel
->r_info
);
1172 #if defined(TCC_TARGET_I386)
1179 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1180 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1181 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1182 /* look at the symbol got offset. If none, then add one */
1183 if (type
== R_386_GOT32
)
1184 reloc_type
= R_386_GLOB_DAT
;
1186 reloc_type
= R_386_JMP_SLOT
;
1187 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1191 #elif defined(TCC_TARGET_ARM)
1198 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1199 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1200 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1201 /* look at the symbol got offset. If none, then add one */
1202 if (type
== R_ARM_GOT32
)
1203 reloc_type
= R_ARM_GLOB_DAT
;
1205 reloc_type
= R_ARM_JUMP_SLOT
;
1206 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1210 case R_ARM_THM_JUMP24
:
1211 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1212 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1213 /* We are relocating a jump from thumb code to arm code */
1214 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1217 char *name
, buf
[1024];
1218 Section
*text_section
;
1220 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1221 text_section
= s1
->sections
[sym
->st_shndx
];
1222 /* Modify reloc to target a thumb stub to switch to ARM */
1223 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1224 index
= put_elf_sym(symtab_section
,
1225 text_section
->data_offset
+ 1,
1226 sym
->st_size
, sym
->st_info
, 0,
1227 sym
->st_shndx
, buf
);
1228 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1229 /* Create a thumb stub fonction to switch to ARM mode */
1230 put_elf_reloc(symtab_section
, text_section
,
1231 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1233 p
= section_ptr_add(text_section
, 8);
1234 put32(p
, 0x4778); /* bx pc */
1235 put32(p
+2, 0x46c0); /* nop */
1236 put32(p
+4, 0xeafffffe); /* b $sym */
1238 #elif defined(TCC_TARGET_C67)
1245 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1246 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1247 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1248 /* look at the symbol got offset. If none, then add one */
1249 if (type
== R_C60_GOT32
)
1250 reloc_type
= R_C60_GLOB_DAT
;
1252 reloc_type
= R_C60_JMP_SLOT
;
1253 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1257 #elif defined(TCC_TARGET_X86_64)
1258 case R_X86_64_GOT32
:
1259 case R_X86_64_GOTTPOFF
:
1260 case R_X86_64_GOTPCREL
:
1261 case R_X86_64_PLT32
:
1264 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1265 type
== R_X86_64_PLT32
) {
1266 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1267 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1268 /* look at the symbol got offset. If none, then add one */
1269 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1270 reloc_type
= R_X86_64_GLOB_DAT
;
1272 reloc_type
= R_X86_64_JUMP_SLOT
;
1273 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1278 #error unsupported CPU
1287 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1288 const char *symtab_name
, int sh_type
, int sh_flags
,
1289 const char *strtab_name
,
1290 const char *hash_name
, int hash_sh_flags
)
1292 Section
*symtab
, *strtab
, *hash
;
1293 int *ptr
, nb_buckets
;
1295 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1296 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1297 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1298 put_elf_str(strtab
, "");
1299 symtab
->link
= strtab
;
1300 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1304 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1305 hash
->sh_entsize
= sizeof(int);
1306 symtab
->hash
= hash
;
1307 hash
->link
= symtab
;
1309 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1310 ptr
[0] = nb_buckets
;
1312 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1316 /* put dynamic tag */
1317 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1320 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1322 dyn
->d_un
.d_val
= val
;
1325 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1329 char sym_start
[1024];
1332 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1333 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1335 s
= find_section(s1
, section_name
);
1340 end_offset
= s
->data_offset
;
1343 add_elf_sym(symtab_section
,
1345 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1346 s
->sh_num
, sym_start
);
1347 add_elf_sym(symtab_section
,
1349 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1350 s
->sh_num
, sym_end
);
1353 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1355 #ifdef CONFIG_TCC_BCHECK
1357 Section
*init_section
;
1358 unsigned char *pinit
;
1361 if (0 == s1
->do_bounds_check
)
1364 /* XXX: add an object file to do that */
1365 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1367 add_elf_sym(symtab_section
, 0, 0,
1368 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1369 bounds_section
->sh_num
, "__bounds_start");
1370 #ifdef TCC_TARGET_I386
1371 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1372 /* add 'call __bound_init()' in .init section */
1373 init_section
= find_section(s1
, ".init");
1374 pinit
= section_ptr_add(init_section
, 5);
1376 put32(pinit
+ 1, -4);
1377 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1378 put_elf_reloc(symtab_section
, init_section
,
1379 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1385 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1388 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1389 return tcc_add_file(s1
, buf
);
1392 /* add tcc runtime libraries */
1393 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1396 if (!s1
->nostdlib
) {
1397 tcc_add_library(s1
, "c");
1398 #ifdef CONFIG_USE_LIBGCC
1399 if (!s1
->static_link
) {
1400 tcc_add_file(s1
, TCC_LIBGCC
);
1401 tcc_add_support(s1
, "libtcc1.a");
1403 tcc_add_support(s1
, "libtcc1.a");
1405 tcc_add_support(s1
, "libtcc1.a");
1409 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1410 libtcc1.a must be loaded before for __bound_init to be defined and
1411 crtn.o must be loaded after to not finalize _init too early. */
1414 if (!s1
->nostdlib
) {
1415 /* add crt end if not memory output */
1416 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1417 tcc_add_crt(s1
, "crtn.o");
1421 /* add various standard linker symbols (must be done after the
1422 sections are filled (for example after allocating common
1424 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1430 add_elf_sym(symtab_section
,
1431 text_section
->data_offset
, 0,
1432 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1433 text_section
->sh_num
, "_etext");
1434 add_elf_sym(symtab_section
,
1435 data_section
->data_offset
, 0,
1436 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1437 data_section
->sh_num
, "_edata");
1438 add_elf_sym(symtab_section
,
1439 bss_section
->data_offset
, 0,
1440 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1441 bss_section
->sh_num
, "_end");
1442 /* horrible new standard ldscript defines */
1443 add_init_array_defines(s1
, ".preinit_array");
1444 add_init_array_defines(s1
, ".init_array");
1445 add_init_array_defines(s1
, ".fini_array");
1447 /* add start and stop symbols for sections whose name can be
1449 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1450 s
= s1
->sections
[i
];
1451 if (s
->sh_type
== SHT_PROGBITS
&&
1452 (s
->sh_flags
& SHF_ALLOC
)) {
1456 /* check if section name can be expressed in C */
1462 if (!isid(ch
) && !isnum(ch
))
1466 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1467 add_elf_sym(symtab_section
,
1469 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1471 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1472 add_elf_sym(symtab_section
,
1474 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1481 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1482 const int *sec_order
)
1485 int i
, offset
, size
;
1488 for(i
=1;i
<s1
->nb_sections
;i
++) {
1489 s
= s1
->sections
[sec_order
[i
]];
1490 if (s
->sh_type
!= SHT_NOBITS
&&
1491 (s
->sh_flags
& SHF_ALLOC
)) {
1492 while (offset
< s
->sh_offset
) {
1497 fwrite(s
->data
, 1, size
, f
);
1503 #if 1 // this allow valgrind to work on linux //defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1505 #define EXTRA_RELITEMS 14
1507 /* move the relocation value from .dynsym to .got */
1508 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1510 uint32_t *gotd
= (void *)s1
->got
->data
;
1513 gotd
+= 3; /* dummy entries in .got */
1514 /* relocate symbols in .dynsym */
1515 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1516 if (sym
->st_shndx
== SHN_UNDEF
) {
1517 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1524 #define EXTRA_RELITEMS 9
1526 /* zero plt offsets of weak symbols in .dynsym */
1527 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1531 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1532 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1537 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1539 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1540 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1541 unsigned long offset
;
1543 if (sym_index
>= s1
->nb_sym_attrs
)
1545 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1546 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1547 #ifdef TCC_TARGET_X86_64
1548 /* only works for x86-64 */
1549 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1551 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1554 /* Perform relocation to GOT or PLTÂ entries */
1555 ST_FUNC
void fill_got(TCCState
*s1
)
1561 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1562 s
= s1
->sections
[i
];
1563 if (s
->sh_type
!= SHT_RELX
)
1565 /* no need to handle got relocations */
1566 if (s
->link
!= symtab_section
)
1568 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1569 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1570 case R_X86_64_GOT32
:
1571 case R_X86_64_GOTPCREL
:
1572 case R_X86_64_PLT32
:
1573 fill_got_entry(s1
, rel
);
1580 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1581 in shared libraries and export non local defined symbols to shared libraries
1582 if -rdynamic switch was given on command line */
1583 static void bind_exe_dynsyms(TCCState
*s1
)
1586 int sym_index
, index
;
1587 ElfW(Sym
) *sym
, *esym
;
1590 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1591 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1592 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1593 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1594 if (sym
->st_shndx
== SHN_UNDEF
) {
1595 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1596 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1598 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1599 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1600 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1601 /* Indirect functions shall have STT_FUNC type in executable
1602 * dynsym section. Indeed, a dlsym call following a lazy
1603 * resolution would pick the symbol value from the
1604 * executable dynsym entry which would contain the address
1605 * of the function wanted by the caller of dlsym instead of
1606 * the address of the function that would return that
1608 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1609 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1610 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1611 } else if (type
== STT_OBJECT
) {
1612 unsigned long offset
;
1614 offset
= bss_section
->data_offset
;
1615 /* XXX: which alignment ? */
1616 offset
= (offset
+ 16 - 1) & -16;
1617 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1618 esym
->st_info
, 0, bss_section
->sh_num
,
1620 /* Ensure R_COPY works for weak symbol aliases */
1621 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1622 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1623 if ((dynsym
->st_value
== esym
->st_value
)
1624 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1625 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1627 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1629 bss_section
->sh_num
, dynname
);
1634 put_elf_reloc(s1
->dynsym
, bss_section
,
1635 offset
, R_COPY
, index
);
1636 offset
+= esym
->st_size
;
1637 bss_section
->data_offset
= offset
;
1640 /* STB_WEAK undefined symbols are accepted */
1641 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1642 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1643 !strcmp(name
, "_fp_hw")) {
1645 tcc_error_noabort("undefined symbol '%s'", name
);
1648 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1649 /* if -rdynamic option, then export all non local symbols */
1650 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1651 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1652 0, sym
->st_shndx
, name
);
1657 /* Bind symbols of libraries: export non local symbols of executable that
1658 resolve undefined symbols of shared libraries */
1659 static void bind_libs_dynsyms(TCCState
*s1
)
1663 ElfW(Sym
) *sym
, *esym
;
1665 /* now look at unresolved dynamic symbols and export
1666 corresponding symbol */
1667 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1668 if (esym
->st_shndx
== SHN_UNDEF
) {
1669 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1670 sym_index
= find_elf_sym(symtab_section
, name
);
1672 /* XXX: avoid adding a symbol if already present because of
1674 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1675 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1676 sym
->st_info
, 0, sym
->st_shndx
, name
);
1678 /* weak symbols can stay undefined */
1679 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1680 tcc_warning("undefined dynamic symbol '%s'", name
);
1686 /* Export all non local symbols (for shared libraries) */
1687 static void export_global_syms(TCCState
*s1
)
1689 int nb_syms
, dynindex
, index
;
1693 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1694 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1695 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1696 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1697 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1698 int type
= ELFW(ST_TYPE
)(sym
->st_info
);
1699 if ((type
== STT_FUNC
|| type
== STT_GNU_IFUNC
)
1700 && sym
->st_shndx
== SHN_UNDEF
) {
1701 int visibility
= ELFW(ST_BIND
)(sym
->st_info
);
1702 put_got_entry(s1
, R_JMP_SLOT
, sym
->st_size
,
1703 ELFW(ST_INFO
)(visibility
, STT_FUNC
),
1704 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1705 } else if (type
== STT_OBJECT
) {
1706 put_got_entry(s1
, R_X86_64_GLOB_DAT
, sym
->st_size
, sym
->st_info
,
1707 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1711 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1712 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1713 sym
->st_info
, 0, sym
->st_shndx
, name
);
1714 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1715 s1
->symtab_to_dynsym
[index
] = dynindex
;
1721 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1722 address for PLT and GOT are known (see fill_program_header) */
1723 static void relocate_plt(TCCState
*s1
)
1728 p_end
= p
+ s1
->plt
->data_offset
;
1730 #if defined(TCC_TARGET_I386)
1731 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1732 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1735 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1738 #elif defined(TCC_TARGET_X86_64)
1739 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1740 put32(p
+ 2, get32(p
+ 2) + x
);
1741 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1744 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1747 #elif defined(TCC_TARGET_ARM)
1749 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1752 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1754 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1757 #elif defined(TCC_TARGET_C67)
1760 #error unsupported CPU
1765 /* Allocate strings for section names and decide if an unallocated section
1768 NOTE: the strsec section comes last, so its size is also correct ! */
1769 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1774 /* Allocate strings for section names */
1775 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1776 s
= s1
->sections
[i
];
1777 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1778 /* when generating a DLL, we include relocations but we may
1780 if (file_type
== TCC_OUTPUT_DLL
&&
1781 s
->sh_type
== SHT_RELX
&&
1782 !(s
->sh_flags
& SHF_ALLOC
)) {
1783 /* gr: avoid bogus relocs for empty (debug) sections */
1784 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1785 prepare_dynamic_rel(s1
, s
);
1786 else if (s1
->do_debug
)
1787 s
->sh_size
= s
->data_offset
;
1788 } else if (s1
->do_debug
||
1789 file_type
== TCC_OUTPUT_OBJ
||
1790 (s
->sh_flags
& SHF_ALLOC
) ||
1791 i
== (s1
->nb_sections
- 1)) {
1792 /* we output all sections if debug or object file */
1793 s
->sh_size
= s
->data_offset
;
1798 /* Info to be copied in dynamic section */
1802 unsigned long dyn_rel_off
;
1805 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1811 /* Assign sections to segments and decide how are sections laid out when loaded
1812 in memory. This function also fills corresponding program headers. */
1813 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1814 Section
*interp
, struct dyn_inf
*dyninf
,
1817 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1823 file_type
= s1
->output_type
;
1825 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1826 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1831 if (s1
->has_text_addr
) {
1832 int a_offset
, p_offset
;
1833 addr
= s1
->text_addr
;
1834 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1836 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1837 p_offset
= file_offset
& (s1
->section_align
- 1);
1838 if (a_offset
< p_offset
)
1839 a_offset
+= s1
->section_align
;
1840 file_offset
+= (a_offset
- p_offset
);
1842 if (file_type
== TCC_OUTPUT_DLL
)
1845 addr
= ELF_START_ADDR
;
1846 /* compute address after headers */
1847 addr
+= (file_offset
& (s1
->section_align
- 1));
1851 /* Leave one program headers for the program interpreter and one for
1852 the program header table itself if needed. These are done later as
1853 they require section layout to be done first. */
1855 ph
+= 1 + HAVE_PHDR
;
1857 /* dynamic relocation table information, for .dynamic section */
1858 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1859 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1860 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1863 for(j
= 0; j
< 2; j
++) {
1864 ph
->p_type
= PT_LOAD
;
1866 ph
->p_flags
= PF_R
| PF_X
;
1868 ph
->p_flags
= PF_R
| PF_W
;
1869 ph
->p_align
= s1
->section_align
;
1871 /* Decide the layout of sections loaded in memory. This must
1872 be done before program headers are filled since they contain
1873 info about the layout. We do the following ordering: interp,
1874 symbol tables, relocations, progbits, nobits */
1875 /* XXX: do faster and simpler sorting */
1876 for(k
= 0; k
< 5; k
++) {
1877 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1878 s
= s1
->sections
[i
];
1879 /* compute if section should be included */
1881 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1885 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1886 (SHF_ALLOC
| SHF_WRITE
))
1892 } else if (s
->sh_type
== SHT_DYNSYM
||
1893 s
->sh_type
== SHT_STRTAB
||
1894 s
->sh_type
== SHT_HASH
) {
1897 } else if (s
->sh_type
== SHT_RELX
) {
1900 } else if (s
->sh_type
== SHT_NOBITS
) {
1907 sec_order
[sh_order_index
++] = i
;
1909 /* section matches: we align it and add its size */
1911 addr
= (addr
+ s
->sh_addralign
- 1) &
1912 ~(s
->sh_addralign
- 1);
1913 file_offset
+= (int) ( addr
- tmp
);
1914 s
->sh_offset
= file_offset
;
1917 /* update program header infos */
1918 if (ph
->p_offset
== 0) {
1919 ph
->p_offset
= file_offset
;
1921 ph
->p_paddr
= ph
->p_vaddr
;
1923 /* update dynamic relocation infos */
1924 if (s
->sh_type
== SHT_RELX
) {
1925 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1926 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1927 dyninf
->rel_addr
= addr
;
1928 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1930 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1931 dyninf
->bss_addr
= addr
;
1932 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1935 if (dyninf
->rel_size
== 0)
1936 dyninf
->rel_addr
= addr
;
1937 dyninf
->rel_size
+= s
->sh_size
;
1941 if (s
->sh_type
!= SHT_NOBITS
)
1942 file_offset
+= s
->sh_size
;
1945 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1946 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1949 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1950 /* if in the middle of a page, we duplicate the page in
1951 memory so that one copy is RX and the other is RW */
1952 if ((addr
& (s1
->section_align
- 1)) != 0)
1953 addr
+= s1
->section_align
;
1955 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1956 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1957 ~(s1
->section_align
- 1);
1963 /* all other sections come after */
1964 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1965 s
= s1
->sections
[i
];
1966 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
1968 sec_order
[sh_order_index
++] = i
;
1970 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
1971 ~(s
->sh_addralign
- 1);
1972 s
->sh_offset
= file_offset
;
1973 if (s
->sh_type
!= SHT_NOBITS
)
1974 file_offset
+= s
->sh_size
;
1980 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
1985 /* if interpreter, then add corresponding program header */
1991 int len
= phnum
* sizeof(ElfW(Phdr
));
1993 ph
->p_type
= PT_PHDR
;
1994 ph
->p_offset
= sizeof(ElfW(Ehdr
));
1995 ph
->p_vaddr
= interp
->sh_addr
- len
;
1996 ph
->p_paddr
= ph
->p_vaddr
;
1997 ph
->p_filesz
= ph
->p_memsz
= len
;
1998 ph
->p_flags
= PF_R
| PF_X
;
1999 ph
->p_align
= 4; /* interp->sh_addralign; */
2003 ph
->p_type
= PT_INTERP
;
2004 ph
->p_offset
= interp
->sh_offset
;
2005 ph
->p_vaddr
= interp
->sh_addr
;
2006 ph
->p_paddr
= ph
->p_vaddr
;
2007 ph
->p_filesz
= interp
->sh_size
;
2008 ph
->p_memsz
= interp
->sh_size
;
2010 ph
->p_align
= interp
->sh_addralign
;
2013 /* if dynamic section, then add corresponding program header */
2015 ph
= &phdr
[phnum
- 1];
2017 ph
->p_type
= PT_DYNAMIC
;
2018 ph
->p_offset
= dynamic
->sh_offset
;
2019 ph
->p_vaddr
= dynamic
->sh_addr
;
2020 ph
->p_paddr
= ph
->p_vaddr
;
2021 ph
->p_filesz
= dynamic
->sh_size
;
2022 ph
->p_memsz
= dynamic
->sh_size
;
2023 ph
->p_flags
= PF_R
| PF_W
;
2024 ph
->p_align
= dynamic
->sh_addralign
;
2028 /* Fill the dynamic section with tags describing the address and size of
2030 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2034 dynamic
= dyninf
->dynamic
;
2036 /* put dynamic section entries */
2037 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2038 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2039 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2040 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2041 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2042 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2043 #ifdef TCC_TARGET_X86_64
2044 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2045 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2046 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2048 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2049 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2050 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2051 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2052 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2053 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2054 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2056 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2057 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2058 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2062 put_dt(dynamic
, DT_DEBUG
, 0);
2063 put_dt(dynamic
, DT_NULL
, 0);
2066 /* Relocate remaining sections and symbols (that is those not related to
2068 static int final_sections_reloc(TCCState
*s1
)
2073 relocate_syms(s1
, 0);
2075 if (s1
->nb_errors
!= 0)
2078 /* relocate sections */
2079 /* XXX: ignore sections with allocated relocations ? */
2080 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2081 s
= s1
->sections
[i
];
2082 if (s
->reloc
&& s
!= s1
->got
)
2083 relocate_section(s1
, s
);
2086 /* relocate relocation entries if the relocation tables are
2087 allocated in the executable */
2088 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2089 s
= s1
->sections
[i
];
2090 if ((s
->sh_flags
& SHF_ALLOC
) &&
2091 s
->sh_type
== SHT_RELX
) {
2092 relocate_rel(s1
, s
);
2098 /* Create an ELF file on disk.
2099 This function handle ELF specific layout requirements */
2100 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2101 int file_offset
, int *sec_order
)
2103 int i
, shnum
, offset
, size
, file_type
;
2106 ElfW(Shdr
) shdr
, *sh
;
2108 file_type
= s1
->output_type
;
2109 shnum
= s1
->nb_sections
;
2111 memset(&ehdr
, 0, sizeof(ehdr
));
2114 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2115 ehdr
.e_phnum
= phnum
;
2116 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2120 file_offset
= (file_offset
+ 3) & -4;
2123 ehdr
.e_ident
[0] = ELFMAG0
;
2124 ehdr
.e_ident
[1] = ELFMAG1
;
2125 ehdr
.e_ident
[2] = ELFMAG2
;
2126 ehdr
.e_ident
[3] = ELFMAG3
;
2127 ehdr
.e_ident
[4] = ELFCLASSW
;
2128 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2129 ehdr
.e_ident
[6] = EV_CURRENT
;
2130 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2131 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2133 #ifdef TCC_TARGET_ARM
2135 ehdr
.e_ident
[EI_OSABI
] = 0;
2136 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2137 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2138 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2139 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2140 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2142 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2144 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2149 case TCC_OUTPUT_EXE
:
2150 ehdr
.e_type
= ET_EXEC
;
2151 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2153 case TCC_OUTPUT_DLL
:
2154 ehdr
.e_type
= ET_DYN
;
2155 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2157 case TCC_OUTPUT_OBJ
:
2158 ehdr
.e_type
= ET_REL
;
2161 ehdr
.e_machine
= EM_TCC_TARGET
;
2162 ehdr
.e_version
= EV_CURRENT
;
2163 ehdr
.e_shoff
= file_offset
;
2164 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2165 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2166 ehdr
.e_shnum
= shnum
;
2167 ehdr
.e_shstrndx
= shnum
- 1;
2169 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2170 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2171 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2173 sort_syms(s1
, symtab_section
);
2174 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2175 s
= s1
->sections
[sec_order
[i
]];
2176 if (s
->sh_type
!= SHT_NOBITS
) {
2177 if (s
->sh_type
== SHT_DYNSYM
)
2178 patch_dynsym_undef(s1
, s
);
2179 while (offset
< s
->sh_offset
) {
2184 fwrite(s
->data
, 1, size
, f
);
2189 /* output section headers */
2190 while (offset
< ehdr
.e_shoff
) {
2195 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2197 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2198 s
= s1
->sections
[i
];
2200 sh
->sh_name
= s
->sh_name
;
2201 sh
->sh_type
= s
->sh_type
;
2202 sh
->sh_flags
= s
->sh_flags
;
2203 sh
->sh_entsize
= s
->sh_entsize
;
2204 sh
->sh_info
= s
->sh_info
;
2206 sh
->sh_link
= s
->link
->sh_num
;
2207 sh
->sh_addralign
= s
->sh_addralign
;
2208 sh
->sh_addr
= s
->sh_addr
;
2209 sh
->sh_offset
= s
->sh_offset
;
2210 sh
->sh_size
= s
->sh_size
;
2212 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2216 /* Write an elf, coff or "binary" file */
2217 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2218 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2220 int fd
, mode
, file_type
;
2223 file_type
= s1
->output_type
;
2224 if (file_type
== TCC_OUTPUT_OBJ
)
2229 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2231 tcc_error_noabort("could not write '%s'", filename
);
2234 f
= fdopen(fd
, "wb");
2236 printf("<- %s\n", filename
);
2238 #ifdef TCC_TARGET_COFF
2239 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2240 tcc_output_coff(s1
, f
);
2243 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2244 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2246 tcc_output_binary(s1
, f
, sec_order
);
2252 /* Output an elf, coff or binary file */
2253 /* XXX: suppress unneeded sections */
2254 static int elf_output_file(TCCState
*s1
, const char *filename
)
2256 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2257 struct dyn_inf dyninf
;
2260 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2262 file_type
= s1
->output_type
;
2265 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2266 if (file_type
!= TCC_OUTPUT_OBJ
) {
2267 tcc_add_runtime(s1
);
2272 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2273 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2275 if (file_type
!= TCC_OUTPUT_OBJ
) {
2276 relocate_common_syms();
2278 tcc_add_linker_symbols(s1
);
2280 if (!s1
->static_link
) {
2281 if (file_type
== TCC_OUTPUT_EXE
) {
2283 /* allow override the dynamic loader */
2284 const char *elfint
= getenv("LD_SO");
2286 elfint
= DEFAULT_ELFINTERP(s1
);
2287 /* add interpreter section only if executable */
2288 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2289 interp
->sh_addralign
= 1;
2290 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2291 strcpy(ptr
, elfint
);
2294 /* add dynamic symbol table */
2295 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2297 ".hash", SHF_ALLOC
);
2298 dynstr
= s1
->dynsym
->link
;
2300 /* add dynamic section */
2301 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2302 SHF_ALLOC
| SHF_WRITE
);
2303 dynamic
->link
= dynstr
;
2304 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2307 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2308 SHF_ALLOC
| SHF_EXECINSTR
);
2309 s1
->plt
->sh_entsize
= 4;
2313 if (file_type
== TCC_OUTPUT_EXE
) {
2314 bind_exe_dynsyms(s1
);
2316 if (s1
->nb_errors
) {
2321 bind_libs_dynsyms(s1
);
2322 } else /* shared library case: simply export all global symbols */
2323 export_global_syms(s1
);
2325 build_got_entries(s1
);
2327 /* add a list of needed dlls */
2328 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2329 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2330 if (dllref
->level
== 0)
2331 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2335 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2337 /* XXX: currently, since we do not handle PIC code, we
2338 must relocate the readonly segments */
2339 if (file_type
== TCC_OUTPUT_DLL
) {
2341 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2342 put_dt(dynamic
, DT_TEXTREL
, 0);
2346 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2348 /* add necessary space for other entries */
2349 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2350 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2352 /* still need to build got entries in case of static link */
2353 build_got_entries(s1
);
2357 /* we add a section for symbols */
2358 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2359 put_elf_str(strsec
, "");
2361 /* compute number of sections */
2362 shnum
= s1
->nb_sections
;
2364 /* this array is used to reorder sections in the output file */
2365 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2368 /* compute number of program headers */
2371 case TCC_OUTPUT_OBJ
:
2374 case TCC_OUTPUT_EXE
:
2375 if (!s1
->static_link
)
2376 phnum
= 4 + HAVE_PHDR
;
2380 case TCC_OUTPUT_DLL
:
2385 /* Allocate strings for section names */
2386 alloc_sec_names(s1
, file_type
, strsec
);
2388 /* allocate program segment headers */
2389 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2391 /* compute section to program header mapping */
2392 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2394 /* Fill remaining program header and finalize relocation related to dynamic
2397 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2399 dyninf
.dynamic
= dynamic
;
2400 dyninf
.dynstr
= dynstr
;
2402 fill_dynamic(s1
, &dyninf
);
2404 /* put in GOT the dynamic section address and relocate PLT */
2405 put32(s1
->got
->data
, dynamic
->sh_addr
);
2406 if (file_type
== TCC_OUTPUT_EXE
2407 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2408 || file_type
== TCC_OUTPUT_DLL
2413 /* relocate symbols in .dynsym now that final addresses are known */
2414 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2415 /* relocate to PLT if symbol corresponds to a PLT entry */
2416 if (sym
->st_shndx
== SHN_UNDEF
) {
2418 sym
->st_value
+= s1
->plt
->sh_addr
;
2419 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2420 /* do symbol relocation */
2421 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2427 /* if building executable or DLL, then relocate each section
2428 except the GOT which is already relocated */
2429 if (file_type
!= TCC_OUTPUT_OBJ
) {
2430 ret
= final_sections_reloc(s1
);
2435 /* Perform relocation to GOT or PLTÂ entries */
2436 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2439 /* Create the ELF file with name 'filename' */
2440 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2442 tcc_free(s1
->symtab_to_dynsym
);
2443 tcc_free(sec_order
);
2445 tcc_free(s1
->sym_attrs
);
2446 s1
->sym_attrs
= NULL
;
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 */