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
,
1014 unsigned long offset
;
1020 /* if a got entry already exists for that symbol, no need to add one */
1021 if (sym_index
< s1
->nb_sym_attrs
&&
1022 s1
->sym_attrs
[sym_index
].got_offset
)
1025 alloc_sym_attr(s1
, sym_index
)->got_offset
= s1
->got
->data_offset
;
1028 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1029 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1030 offset
= sym
->st_value
;
1031 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1033 #ifdef TCC_TARGET_X86_64
1043 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1046 /* if we build a DLL, we add a %ebx offset */
1047 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1053 /* add a PLT entry */
1055 if (plt
->data_offset
== 0) {
1056 /* first plt entry */
1057 p
= section_ptr_add(plt
, 16);
1058 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1059 p
[1] = modrm
+ 0x10;
1060 put32(p
+ 2, PTR_SIZE
);
1061 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1063 put32(p
+ 8, PTR_SIZE
* 2);
1066 p
= section_ptr_add(plt
, 16);
1067 p
[0] = 0xff; /* jmp *(got + x) */
1069 put32(p
+ 2, s1
->got
->data_offset
);
1070 p
[6] = 0x68; /* push $xxx */
1071 put32(p
+ 7, (plt
->data_offset
- 32) >> 1);
1072 p
[11] = 0xe9; /* jmp plt_start */
1073 put32(p
+ 12, -(plt
->data_offset
));
1075 /* the symbol is modified so that it will be relocated to
1077 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1078 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1080 offset
= plt
->data_offset
- 16;
1082 #elif defined(TCC_TARGET_ARM)
1083 if (reloc_type
== R_ARM_JUMP_SLOT
) {
1087 /* if we build a DLL, we add a %ebx offset */
1088 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1089 tcc_error("DLLs unimplemented!");
1091 /* add a PLT entry */
1093 if (plt
->data_offset
== 0) {
1094 /* first plt entry */
1095 p
= section_ptr_add(plt
, 16);
1096 put32(p
, 0xe52de004); /* push {lr} */
1097 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1098 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1099 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1102 if (s1
->sym_attrs
[sym_index
].plt_thumb_stub
) {
1103 p
= section_ptr_add(plt
, 20);
1104 put32(p
, 0x4778); /* bx pc */
1105 put32(p
+2, 0x46c0); /* nop */
1108 p
= section_ptr_add(plt
, 16);
1109 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1110 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1111 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1112 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1114 /* the symbol is modified so that it will be relocated to
1116 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1117 offset
= plt
->data_offset
- 16;
1119 #elif defined(TCC_TARGET_C67)
1120 tcc_error("C67 got not implemented");
1122 #error unsupported CPU
1124 index
= put_elf_sym(s1
->dynsym
, offset
,
1125 size
, info
, 0, sym
->st_shndx
, name
);
1126 /* put a got entry */
1127 put_elf_reloc(s1
->dynsym
, s1
->got
,
1128 s1
->got
->data_offset
,
1131 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1135 /* build GOT and PLT entries */
1136 ST_FUNC
void build_got_entries(TCCState
*s1
)
1141 int i
, type
, reloc_type
, sym_index
;
1143 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1144 s
= s1
->sections
[i
];
1145 if (s
->sh_type
!= SHT_RELX
)
1147 /* no need to handle got relocations */
1148 if (s
->link
!= symtab_section
)
1150 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1151 type
= ELFW(R_TYPE
)(rel
->r_info
);
1153 #if defined(TCC_TARGET_I386)
1160 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1161 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1162 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1163 /* look at the symbol got offset. If none, then add one */
1164 if (type
== R_386_GOT32
)
1165 reloc_type
= R_386_GLOB_DAT
;
1167 reloc_type
= R_386_JMP_SLOT
;
1168 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1172 #elif defined(TCC_TARGET_ARM)
1179 if (type
== R_ARM_GOT32
|| type
== R_ARM_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_ARM_GOT32
)
1184 reloc_type
= R_ARM_GLOB_DAT
;
1186 reloc_type
= R_ARM_JUMP_SLOT
;
1187 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1191 case R_ARM_THM_JUMP24
:
1192 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1193 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1194 /* We are relocating a jump from thumb code to arm code */
1195 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1198 char *name
, buf
[1024];
1199 Section
*text_section
;
1201 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1202 text_section
= s1
->sections
[sym
->st_shndx
];
1203 /* Modify reloc to target a thumb stub to switch to ARM */
1204 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1205 index
= put_elf_sym(symtab_section
,
1206 text_section
->data_offset
+ 1,
1207 sym
->st_size
, sym
->st_info
, 0,
1208 sym
->st_shndx
, buf
);
1209 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1210 /* Create a thumb stub fonction to switch to ARM mode */
1211 put_elf_reloc(symtab_section
, text_section
,
1212 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1214 p
= section_ptr_add(text_section
, 8);
1215 put32(p
, 0x4778); /* bx pc */
1216 put32(p
+2, 0x46c0); /* nop */
1217 put32(p
+4, 0xeafffffe); /* b $sym */
1219 #elif defined(TCC_TARGET_C67)
1226 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1227 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1228 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1229 /* look at the symbol got offset. If none, then add one */
1230 if (type
== R_C60_GOT32
)
1231 reloc_type
= R_C60_GLOB_DAT
;
1233 reloc_type
= R_C60_JMP_SLOT
;
1234 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1238 #elif defined(TCC_TARGET_X86_64)
1239 case R_X86_64_GOT32
:
1240 case R_X86_64_GOTTPOFF
:
1241 case R_X86_64_GOTPCREL
:
1242 case R_X86_64_PLT32
:
1245 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1246 type
== R_X86_64_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_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1251 reloc_type
= R_X86_64_GLOB_DAT
;
1253 reloc_type
= R_X86_64_JUMP_SLOT
;
1254 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1259 #error unsupported CPU
1268 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1269 const char *symtab_name
, int sh_type
, int sh_flags
,
1270 const char *strtab_name
,
1271 const char *hash_name
, int hash_sh_flags
)
1273 Section
*symtab
, *strtab
, *hash
;
1274 int *ptr
, nb_buckets
;
1276 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1277 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1278 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1279 put_elf_str(strtab
, "");
1280 symtab
->link
= strtab
;
1281 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1285 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1286 hash
->sh_entsize
= sizeof(int);
1287 symtab
->hash
= hash
;
1288 hash
->link
= symtab
;
1290 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1291 ptr
[0] = nb_buckets
;
1293 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1297 /* put dynamic tag */
1298 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1301 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1303 dyn
->d_un
.d_val
= val
;
1306 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1310 char sym_start
[1024];
1313 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1314 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1316 s
= find_section(s1
, section_name
);
1321 end_offset
= s
->data_offset
;
1324 add_elf_sym(symtab_section
,
1326 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1327 s
->sh_num
, sym_start
);
1328 add_elf_sym(symtab_section
,
1330 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1331 s
->sh_num
, sym_end
);
1334 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1336 #ifdef CONFIG_TCC_BCHECK
1338 Section
*init_section
;
1339 unsigned char *pinit
;
1342 if (0 == s1
->do_bounds_check
)
1345 /* XXX: add an object file to do that */
1346 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1348 add_elf_sym(symtab_section
, 0, 0,
1349 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1350 bounds_section
->sh_num
, "__bounds_start");
1351 #ifdef TCC_TARGET_I386
1352 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1353 /* add 'call __bound_init()' in .init section */
1354 init_section
= find_section(s1
, ".init");
1355 pinit
= section_ptr_add(init_section
, 5);
1357 put32(pinit
+ 1, -4);
1358 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1359 put_elf_reloc(symtab_section
, init_section
,
1360 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1366 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1369 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1370 return tcc_add_file(s1
, buf
);
1373 /* add tcc runtime libraries */
1374 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1379 if (!s1
->nostdlib
) {
1380 tcc_add_library(s1
, "c");
1381 #ifdef CONFIG_USE_LIBGCC
1382 if (!s1
->static_link
)
1383 tcc_add_file(s1
, TCC_LIBGCC
);
1385 tcc_add_support(s1
, "libtcc1.a");
1387 tcc_add_support(s1
, "libtcc1.a");
1389 /* add crt end if not memory output */
1390 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1391 tcc_add_crt(s1
, "crtn.o");
1395 /* add various standard linker symbols (must be done after the
1396 sections are filled (for example after allocating common
1398 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1404 add_elf_sym(symtab_section
,
1405 text_section
->data_offset
, 0,
1406 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1407 text_section
->sh_num
, "_etext");
1408 add_elf_sym(symtab_section
,
1409 data_section
->data_offset
, 0,
1410 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1411 data_section
->sh_num
, "_edata");
1412 add_elf_sym(symtab_section
,
1413 bss_section
->data_offset
, 0,
1414 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1415 bss_section
->sh_num
, "_end");
1416 /* horrible new standard ldscript defines */
1417 add_init_array_defines(s1
, ".preinit_array");
1418 add_init_array_defines(s1
, ".init_array");
1419 add_init_array_defines(s1
, ".fini_array");
1421 /* add start and stop symbols for sections whose name can be
1423 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1424 s
= s1
->sections
[i
];
1425 if (s
->sh_type
== SHT_PROGBITS
&&
1426 (s
->sh_flags
& SHF_ALLOC
)) {
1430 /* check if section name can be expressed in C */
1436 if (!isid(ch
) && !isnum(ch
))
1440 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1441 add_elf_sym(symtab_section
,
1443 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1445 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1446 add_elf_sym(symtab_section
,
1448 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1455 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1456 const int *sec_order
)
1459 int i
, offset
, size
;
1462 for(i
=1;i
<s1
->nb_sections
;i
++) {
1463 s
= s1
->sections
[sec_order
[i
]];
1464 if (s
->sh_type
!= SHT_NOBITS
&&
1465 (s
->sh_flags
& SHF_ALLOC
)) {
1466 while (offset
< s
->sh_offset
) {
1471 fwrite(s
->data
, 1, size
, f
);
1477 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1479 #define EXTRA_RELITEMS 14
1481 /* move the relocation value from .dynsym to .got */
1482 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1484 uint32_t *gotd
= (void *)s1
->got
->data
;
1487 gotd
+= 3; /* dummy entries in .got */
1488 /* relocate symbols in .dynsym */
1489 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1490 if (sym
->st_shndx
== SHN_UNDEF
) {
1491 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1498 #define EXTRA_RELITEMS 9
1500 /* zero plt offsets of weak symbols in .dynsym */
1501 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1505 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1506 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1511 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1513 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1514 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1515 unsigned long offset
;
1517 if (sym_index
>= s1
->nb_sym_attrs
)
1519 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1520 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1521 #ifdef TCC_TARGET_X86_64
1522 /* only works for x86-64 */
1523 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1525 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1528 /* Perform relocation to GOT or PLTÂ entries */
1529 ST_FUNC
void fill_got(TCCState
*s1
)
1535 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1536 s
= s1
->sections
[i
];
1537 if (s
->sh_type
!= SHT_RELX
)
1539 /* no need to handle got relocations */
1540 if (s
->link
!= symtab_section
)
1542 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1543 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1544 case R_X86_64_GOT32
:
1545 case R_X86_64_GOTPCREL
:
1546 case R_X86_64_PLT32
:
1547 fill_got_entry(s1
, rel
);
1554 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1555 in shared libraries and export non local defined symbols to shared libraries
1556 if -rdynamic switch was given on command line */
1557 static void bind_exe_dynsyms(TCCState
*s1
)
1560 int sym_index
, index
;
1561 ElfW(Sym
) *sym
, *esym
;
1564 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1565 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1566 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1567 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1568 if (sym
->st_shndx
== SHN_UNDEF
) {
1569 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1570 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1572 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1573 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1574 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1575 /* Indirect functions shall have STT_FUNC type in executable
1576 * dynsym section. Indeed, a dlsym call following a lazy
1577 * resolution would pick the symbol value from the
1578 * executable dynsym entry which would contain the address
1579 * of the function wanted by the caller of dlsym instead of
1580 * the address of the function that would return that
1582 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1583 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1584 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1585 } else if (type
== STT_OBJECT
) {
1586 unsigned long offset
;
1588 offset
= bss_section
->data_offset
;
1589 /* XXX: which alignment ? */
1590 offset
= (offset
+ 16 - 1) & -16;
1591 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1592 esym
->st_info
, 0, bss_section
->sh_num
,
1594 /* Ensure R_COPY works for weak symbol aliases */
1595 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1596 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1597 if ((dynsym
->st_value
== esym
->st_value
)
1598 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1599 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1601 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1603 bss_section
->sh_num
, dynname
);
1608 put_elf_reloc(s1
->dynsym
, bss_section
,
1609 offset
, R_COPY
, index
);
1610 offset
+= esym
->st_size
;
1611 bss_section
->data_offset
= offset
;
1614 /* STB_WEAK undefined symbols are accepted */
1615 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1616 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1617 !strcmp(name
, "_fp_hw")) {
1619 tcc_error_noabort("undefined symbol '%s'", name
);
1622 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1623 /* if -rdynamic option, then export all non local symbols */
1624 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1625 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1626 0, sym
->st_shndx
, name
);
1631 /* Bind symbols of libraries: export non local symbols of executable that
1632 resolve undefined symbols of shared libraries */
1633 static void bind_libs_dynsyms(TCCState
*s1
)
1637 ElfW(Sym
) *sym
, *esym
;
1639 /* now look at unresolved dynamic symbols and export
1640 corresponding symbol */
1641 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1642 if (esym
->st_shndx
== SHN_UNDEF
) {
1643 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1644 sym_index
= find_elf_sym(symtab_section
, name
);
1646 /* XXX: avoid adding a symbol if already present because of
1648 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1649 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1650 sym
->st_info
, 0, sym
->st_shndx
, name
);
1652 /* weak symbols can stay undefined */
1653 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1654 tcc_warning("undefined dynamic symbol '%s'", name
);
1660 /* Export all non local symbols (for shared libraries) */
1661 static void export_global_syms(TCCState
*s1
)
1663 int nb_syms
, dynindex
, index
;
1667 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1668 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1669 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1670 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1671 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1672 int type
= ELFW(ST_TYPE
)(sym
->st_info
);
1673 if ((type
== STT_FUNC
|| type
== STT_GNU_IFUNC
)
1674 && sym
->st_shndx
== SHN_UNDEF
) {
1675 int visibility
= ELFW(ST_BIND
)(sym
->st_info
);
1676 put_got_entry(s1
, R_JMP_SLOT
, sym
->st_size
,
1677 ELFW(ST_INFO
)(visibility
, STT_FUNC
),
1678 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1679 } else if (type
== STT_OBJECT
) {
1680 put_got_entry(s1
, R_X86_64_GLOB_DAT
, sym
->st_size
, sym
->st_info
,
1681 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1685 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1686 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1687 sym
->st_info
, 0, sym
->st_shndx
, name
);
1688 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1689 s1
->symtab_to_dynsym
[index
] = dynindex
;
1695 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1696 address for PLT and GOT are known (see fill_program_header) */
1697 static void relocate_plt(TCCState
*s1
)
1702 p_end
= p
+ s1
->plt
->data_offset
;
1704 #if defined(TCC_TARGET_I386)
1705 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1706 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1709 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1712 #elif defined(TCC_TARGET_X86_64)
1713 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1714 put32(p
+ 2, get32(p
+ 2) + x
);
1715 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1718 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1721 #elif defined(TCC_TARGET_ARM)
1723 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1726 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1728 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1731 #elif defined(TCC_TARGET_C67)
1734 #error unsupported CPU
1739 /* Allocate strings for section names and decide if an unallocated section
1742 NOTE: the strsec section comes last, so its size is also correct ! */
1743 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1748 /* Allocate strings for section names */
1749 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1750 s
= s1
->sections
[i
];
1751 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1752 /* when generating a DLL, we include relocations but we may
1754 if (file_type
== TCC_OUTPUT_DLL
&&
1755 s
->sh_type
== SHT_RELX
&&
1756 !(s
->sh_flags
& SHF_ALLOC
)) {
1757 /* gr: avoid bogus relocs for empty (debug) sections */
1758 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1759 prepare_dynamic_rel(s1
, s
);
1760 else if (s1
->do_debug
)
1761 s
->sh_size
= s
->data_offset
;
1762 } else if (s1
->do_debug
||
1763 file_type
== TCC_OUTPUT_OBJ
||
1764 (s
->sh_flags
& SHF_ALLOC
) ||
1765 i
== (s1
->nb_sections
- 1)) {
1766 /* we output all sections if debug or object file */
1767 s
->sh_size
= s
->data_offset
;
1772 /* Info to be copied in dynamic section */
1776 unsigned long dyn_rel_off
;
1779 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1785 /* Assign sections to segments and decide how are sections laid out when loaded
1786 in memory. This function also fills corresponding program headers. */
1787 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1788 Section
*interp
, struct dyn_inf
*dyninf
,
1791 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1797 file_type
= s1
->output_type
;
1799 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1800 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1805 if (s1
->has_text_addr
) {
1806 int a_offset
, p_offset
;
1807 addr
= s1
->text_addr
;
1808 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1810 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1811 p_offset
= file_offset
& (s1
->section_align
- 1);
1812 if (a_offset
< p_offset
)
1813 a_offset
+= s1
->section_align
;
1814 file_offset
+= (a_offset
- p_offset
);
1816 if (file_type
== TCC_OUTPUT_DLL
)
1819 addr
= ELF_START_ADDR
;
1820 /* compute address after headers */
1821 addr
+= (file_offset
& (s1
->section_align
- 1));
1825 /* Leave one program headers for the program interpreter and one for
1826 the program header table itself if needed. These are done later as
1827 they require section layout to be done first. */
1829 ph
+= 1 + HAVE_PHDR
;
1831 /* dynamic relocation table information, for .dynamic section */
1832 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1833 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1834 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1837 for(j
= 0; j
< 2; j
++) {
1838 ph
->p_type
= PT_LOAD
;
1840 ph
->p_flags
= PF_R
| PF_X
;
1842 ph
->p_flags
= PF_R
| PF_W
;
1843 ph
->p_align
= s1
->section_align
;
1845 /* Decide the layout of sections loaded in memory. This must
1846 be done before program headers are filled since they contain
1847 info about the layout. We do the following ordering: interp,
1848 symbol tables, relocations, progbits, nobits */
1849 /* XXX: do faster and simpler sorting */
1850 for(k
= 0; k
< 5; k
++) {
1851 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1852 s
= s1
->sections
[i
];
1853 /* compute if section should be included */
1855 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1859 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1860 (SHF_ALLOC
| SHF_WRITE
))
1866 } else if (s
->sh_type
== SHT_DYNSYM
||
1867 s
->sh_type
== SHT_STRTAB
||
1868 s
->sh_type
== SHT_HASH
) {
1871 } else if (s
->sh_type
== SHT_RELX
) {
1874 } else if (s
->sh_type
== SHT_NOBITS
) {
1881 sec_order
[sh_order_index
++] = i
;
1883 /* section matches: we align it and add its size */
1885 addr
= (addr
+ s
->sh_addralign
- 1) &
1886 ~(s
->sh_addralign
- 1);
1887 file_offset
+= (int) ( addr
- tmp
);
1888 s
->sh_offset
= file_offset
;
1891 /* update program header infos */
1892 if (ph
->p_offset
== 0) {
1893 ph
->p_offset
= file_offset
;
1895 ph
->p_paddr
= ph
->p_vaddr
;
1897 /* update dynamic relocation infos */
1898 if (s
->sh_type
== SHT_RELX
) {
1899 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1900 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1901 dyninf
->rel_addr
= addr
;
1902 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1904 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1905 dyninf
->bss_addr
= addr
;
1906 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1909 if (dyninf
->rel_size
== 0)
1910 dyninf
->rel_addr
= addr
;
1911 dyninf
->rel_size
+= s
->sh_size
;
1915 if (s
->sh_type
!= SHT_NOBITS
)
1916 file_offset
+= s
->sh_size
;
1919 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1920 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1923 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1924 /* if in the middle of a page, we duplicate the page in
1925 memory so that one copy is RX and the other is RW */
1926 if ((addr
& (s1
->section_align
- 1)) != 0)
1927 addr
+= s1
->section_align
;
1929 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1930 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1931 ~(s1
->section_align
- 1);
1937 /* all other sections come after */
1938 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1939 s
= s1
->sections
[i
];
1940 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
1942 sec_order
[sh_order_index
++] = i
;
1944 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
1945 ~(s
->sh_addralign
- 1);
1946 s
->sh_offset
= file_offset
;
1947 if (s
->sh_type
!= SHT_NOBITS
)
1948 file_offset
+= s
->sh_size
;
1954 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
1959 /* if interpreter, then add corresponding program header */
1965 int len
= phnum
* sizeof(ElfW(Phdr
));
1967 ph
->p_type
= PT_PHDR
;
1968 ph
->p_offset
= sizeof(ElfW(Ehdr
));
1969 ph
->p_vaddr
= interp
->sh_addr
- len
;
1970 ph
->p_paddr
= ph
->p_vaddr
;
1971 ph
->p_filesz
= ph
->p_memsz
= len
;
1972 ph
->p_flags
= PF_R
| PF_X
;
1973 ph
->p_align
= 4; /* interp->sh_addralign; */
1977 ph
->p_type
= PT_INTERP
;
1978 ph
->p_offset
= interp
->sh_offset
;
1979 ph
->p_vaddr
= interp
->sh_addr
;
1980 ph
->p_paddr
= ph
->p_vaddr
;
1981 ph
->p_filesz
= interp
->sh_size
;
1982 ph
->p_memsz
= interp
->sh_size
;
1984 ph
->p_align
= interp
->sh_addralign
;
1987 /* if dynamic section, then add corresponding program header */
1989 ph
= &phdr
[phnum
- 1];
1991 ph
->p_type
= PT_DYNAMIC
;
1992 ph
->p_offset
= dynamic
->sh_offset
;
1993 ph
->p_vaddr
= dynamic
->sh_addr
;
1994 ph
->p_paddr
= ph
->p_vaddr
;
1995 ph
->p_filesz
= dynamic
->sh_size
;
1996 ph
->p_memsz
= dynamic
->sh_size
;
1997 ph
->p_flags
= PF_R
| PF_W
;
1998 ph
->p_align
= dynamic
->sh_addralign
;
2002 /* Fill the dynamic section with tags describing the address and size of
2004 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2008 dynamic
= dyninf
->dynamic
;
2010 /* put dynamic section entries */
2011 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2012 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2013 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2014 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2015 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2016 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2017 #ifdef TCC_TARGET_X86_64
2018 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2019 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2020 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2022 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2023 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2024 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2025 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2026 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2027 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2028 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2030 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2031 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2032 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2036 put_dt(dynamic
, DT_DEBUG
, 0);
2037 put_dt(dynamic
, DT_NULL
, 0);
2040 /* Relocate remaining sections and symbols (that is those not related to
2042 static int final_sections_reloc(TCCState
*s1
)
2047 relocate_syms(s1
, 0);
2049 if (s1
->nb_errors
!= 0)
2052 /* relocate sections */
2053 /* XXX: ignore sections with allocated relocations ? */
2054 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2055 s
= s1
->sections
[i
];
2056 if (s
->reloc
&& s
!= s1
->got
)
2057 relocate_section(s1
, s
);
2060 /* relocate relocation entries if the relocation tables are
2061 allocated in the executable */
2062 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2063 s
= s1
->sections
[i
];
2064 if ((s
->sh_flags
& SHF_ALLOC
) &&
2065 s
->sh_type
== SHT_RELX
) {
2066 relocate_rel(s1
, s
);
2072 /* Create an ELF file on disk.
2073 This function handle ELF specific layout requirements */
2074 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2075 int file_offset
, int *sec_order
)
2077 int i
, shnum
, offset
, size
, file_type
;
2080 ElfW(Shdr
) shdr
, *sh
;
2082 file_type
= s1
->output_type
;
2083 shnum
= s1
->nb_sections
;
2085 memset(&ehdr
, 0, sizeof(ehdr
));
2088 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2089 ehdr
.e_phnum
= phnum
;
2090 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2094 file_offset
= (file_offset
+ 3) & -4;
2097 ehdr
.e_ident
[0] = ELFMAG0
;
2098 ehdr
.e_ident
[1] = ELFMAG1
;
2099 ehdr
.e_ident
[2] = ELFMAG2
;
2100 ehdr
.e_ident
[3] = ELFMAG3
;
2101 ehdr
.e_ident
[4] = ELFCLASSW
;
2102 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2103 ehdr
.e_ident
[6] = EV_CURRENT
;
2104 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2105 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2107 #ifdef TCC_TARGET_ARM
2109 ehdr
.e_ident
[EI_OSABI
] = 0;
2110 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2111 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2112 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2113 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2114 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2116 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2118 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2123 case TCC_OUTPUT_EXE
:
2124 ehdr
.e_type
= ET_EXEC
;
2125 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2127 case TCC_OUTPUT_DLL
:
2128 ehdr
.e_type
= ET_DYN
;
2129 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2131 case TCC_OUTPUT_OBJ
:
2132 ehdr
.e_type
= ET_REL
;
2135 ehdr
.e_machine
= EM_TCC_TARGET
;
2136 ehdr
.e_version
= EV_CURRENT
;
2137 ehdr
.e_shoff
= file_offset
;
2138 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2139 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2140 ehdr
.e_shnum
= shnum
;
2141 ehdr
.e_shstrndx
= shnum
- 1;
2143 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2144 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2145 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2147 sort_syms(s1
, symtab_section
);
2148 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2149 s
= s1
->sections
[sec_order
[i
]];
2150 if (s
->sh_type
!= SHT_NOBITS
) {
2151 if (s
->sh_type
== SHT_DYNSYM
)
2152 patch_dynsym_undef(s1
, s
);
2153 while (offset
< s
->sh_offset
) {
2158 fwrite(s
->data
, 1, size
, f
);
2163 /* output section headers */
2164 while (offset
< ehdr
.e_shoff
) {
2169 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2171 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2172 s
= s1
->sections
[i
];
2174 sh
->sh_name
= s
->sh_name
;
2175 sh
->sh_type
= s
->sh_type
;
2176 sh
->sh_flags
= s
->sh_flags
;
2177 sh
->sh_entsize
= s
->sh_entsize
;
2178 sh
->sh_info
= s
->sh_info
;
2180 sh
->sh_link
= s
->link
->sh_num
;
2181 sh
->sh_addralign
= s
->sh_addralign
;
2182 sh
->sh_addr
= s
->sh_addr
;
2183 sh
->sh_offset
= s
->sh_offset
;
2184 sh
->sh_size
= s
->sh_size
;
2186 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2190 /* Write an elf, coff or "binary" file */
2191 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2192 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2194 int fd
, mode
, file_type
;
2197 file_type
= s1
->output_type
;
2198 if (file_type
== TCC_OUTPUT_OBJ
)
2203 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2205 tcc_error_noabort("could not write '%s'", filename
);
2208 f
= fdopen(fd
, "wb");
2210 printf("<- %s\n", filename
);
2212 #ifdef TCC_TARGET_COFF
2213 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2214 tcc_output_coff(s1
, f
);
2217 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2218 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2220 tcc_output_binary(s1
, f
, sec_order
);
2226 /* Output an elf, coff or binary file */
2227 /* XXX: suppress unneeded sections */
2228 static int elf_output_file(TCCState
*s1
, const char *filename
)
2230 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2231 struct dyn_inf dyninf
;
2234 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2236 file_type
= s1
->output_type
;
2239 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2240 if (file_type
!= TCC_OUTPUT_OBJ
) {
2241 tcc_add_runtime(s1
);
2246 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2247 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2249 if (file_type
!= TCC_OUTPUT_OBJ
) {
2250 relocate_common_syms();
2252 tcc_add_linker_symbols(s1
);
2254 if (!s1
->static_link
) {
2255 if (file_type
== TCC_OUTPUT_EXE
) {
2257 /* allow override the dynamic loader */
2258 const char *elfint
= getenv("LD_SO");
2260 elfint
= DEFAULT_ELFINTERP(s1
);
2261 /* add interpreter section only if executable */
2262 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2263 interp
->sh_addralign
= 1;
2264 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2265 strcpy(ptr
, elfint
);
2268 /* add dynamic symbol table */
2269 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2271 ".hash", SHF_ALLOC
);
2272 dynstr
= s1
->dynsym
->link
;
2274 /* add dynamic section */
2275 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2276 SHF_ALLOC
| SHF_WRITE
);
2277 dynamic
->link
= dynstr
;
2278 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2281 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2282 SHF_ALLOC
| SHF_EXECINSTR
);
2283 s1
->plt
->sh_entsize
= 4;
2287 if (file_type
== TCC_OUTPUT_EXE
) {
2288 bind_exe_dynsyms(s1
);
2290 if (s1
->nb_errors
) {
2295 bind_libs_dynsyms(s1
);
2296 } else /* shared library case: simply export all global symbols */
2297 export_global_syms(s1
);
2299 build_got_entries(s1
);
2301 /* add a list of needed dlls */
2302 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2303 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2304 if (dllref
->level
== 0)
2305 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2309 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2311 /* XXX: currently, since we do not handle PIC code, we
2312 must relocate the readonly segments */
2313 if (file_type
== TCC_OUTPUT_DLL
) {
2315 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2316 put_dt(dynamic
, DT_TEXTREL
, 0);
2320 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2322 /* add necessary space for other entries */
2323 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2324 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2326 /* still need to build got entries in case of static link */
2327 build_got_entries(s1
);
2331 /* we add a section for symbols */
2332 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2333 put_elf_str(strsec
, "");
2335 /* compute number of sections */
2336 shnum
= s1
->nb_sections
;
2338 /* this array is used to reorder sections in the output file */
2339 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2342 /* compute number of program headers */
2345 case TCC_OUTPUT_OBJ
:
2348 case TCC_OUTPUT_EXE
:
2349 if (!s1
->static_link
)
2350 phnum
= 4 + HAVE_PHDR
;
2354 case TCC_OUTPUT_DLL
:
2359 /* Allocate strings for section names */
2360 alloc_sec_names(s1
, file_type
, strsec
);
2362 /* allocate program segment headers */
2363 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2365 /* compute section to program header mapping */
2366 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2368 /* Fill remaining program header and finalize relocation related to dynamic
2371 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2373 dyninf
.dynamic
= dynamic
;
2374 dyninf
.dynstr
= dynstr
;
2376 fill_dynamic(s1
, &dyninf
);
2378 /* put in GOT the dynamic section address and relocate PLT */
2379 put32(s1
->got
->data
, dynamic
->sh_addr
);
2380 if (file_type
== TCC_OUTPUT_EXE
2381 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2382 || file_type
== TCC_OUTPUT_DLL
2387 /* relocate symbols in .dynsym now that final addresses are known */
2388 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2389 /* relocate to PLT if symbol corresponds to a PLT entry */
2390 if (sym
->st_shndx
== SHN_UNDEF
) {
2392 sym
->st_value
+= s1
->plt
->sh_addr
;
2393 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2394 /* do symbol relocation */
2395 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2401 /* if building executable or DLL, then relocate each section
2402 except the GOT which is already relocated */
2403 if (file_type
!= TCC_OUTPUT_OBJ
) {
2404 ret
= final_sections_reloc(s1
);
2409 /* Perform relocation to GOT or PLTÂ entries */
2410 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2413 /* Create the ELF file with name 'filename' */
2414 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2416 tcc_free(s1
->symtab_to_dynsym
);
2417 tcc_free(sec_order
);
2419 tcc_free(s1
->sym_attrs
);
2423 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2426 #ifdef TCC_TARGET_PE
2427 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2428 ret
= pe_output_file(s
, filename
);
2431 ret
= elf_output_file(s
, filename
);
2435 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2439 data
= tcc_malloc(size
);
2440 lseek(fd
, file_offset
, SEEK_SET
);
2441 read(fd
, data
, size
);
2445 typedef struct SectionMergeInfo
{
2446 Section
*s
; /* corresponding existing section */
2447 unsigned long offset
; /* offset of the new section in the existing section */
2448 uint8_t new_section
; /* true if section 's' was added */
2449 uint8_t link_once
; /* true if link once section */
2452 /* load an object file and merge it with current files */
2453 /* XXX: handle correctly stab (debug) info */
2454 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2455 int fd
, unsigned long file_offset
)
2458 ElfW(Shdr
) *shdr
, *sh
;
2459 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2460 unsigned char *strsec
, *strtab
;
2461 int *old_to_new_syms
;
2462 char *sh_name
, *name
;
2463 SectionMergeInfo
*sm_table
, *sm
;
2464 ElfW(Sym
) *sym
, *symtab
;
2471 stab_index
= stabstr_index
= 0;
2473 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2475 if (ehdr
.e_ident
[0] != ELFMAG0
||
2476 ehdr
.e_ident
[1] != ELFMAG1
||
2477 ehdr
.e_ident
[2] != ELFMAG2
||
2478 ehdr
.e_ident
[3] != ELFMAG3
)
2480 /* test if object file */
2481 if (ehdr
.e_type
!= ET_REL
)
2483 /* test CPU specific stuff */
2484 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2485 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2487 tcc_error_noabort("invalid object file");
2491 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2492 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2493 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2495 /* load section names */
2496 sh
= &shdr
[ehdr
.e_shstrndx
];
2497 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2499 /* load symtab and strtab */
2500 old_to_new_syms
= NULL
;
2504 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2506 if (sh
->sh_type
== SHT_SYMTAB
) {
2508 tcc_error_noabort("object must contain only one symtab");
2513 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2514 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2515 sm_table
[i
].s
= symtab_section
;
2517 /* now load strtab */
2518 sh
= &shdr
[sh
->sh_link
];
2519 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2523 /* now examine each section and try to merge its content with the
2525 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2526 /* no need to examine section name strtab */
2527 if (i
== ehdr
.e_shstrndx
)
2530 sh_name
= (char *) strsec
+ sh
->sh_name
;
2531 /* ignore sections types we do not handle */
2532 if (sh
->sh_type
!= SHT_PROGBITS
&&
2533 sh
->sh_type
!= SHT_RELX
&&
2535 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2537 sh
->sh_type
!= SHT_NOBITS
&&
2538 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2539 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2540 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2541 strcmp(sh_name
, ".stabstr")
2544 if (sh
->sh_addralign
< 1)
2545 sh
->sh_addralign
= 1;
2546 /* find corresponding section, if any */
2547 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2548 s
= s1
->sections
[j
];
2549 if (!strcmp(s
->name
, sh_name
)) {
2550 if (!strncmp(sh_name
, ".gnu.linkonce",
2551 sizeof(".gnu.linkonce") - 1)) {
2552 /* if a 'linkonce' section is already present, we
2553 do not add it again. It is a little tricky as
2554 symbols can still be defined in
2556 sm_table
[i
].link_once
= 1;
2563 /* not found: create new section */
2564 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2565 /* take as much info as possible from the section. sh_link and
2566 sh_info will be updated later */
2567 s
->sh_addralign
= sh
->sh_addralign
;
2568 s
->sh_entsize
= sh
->sh_entsize
;
2569 sm_table
[i
].new_section
= 1;
2571 if (sh
->sh_type
!= s
->sh_type
) {
2572 tcc_error_noabort("invalid section type");
2576 /* align start of section */
2577 offset
= s
->data_offset
;
2579 if (0 == strcmp(sh_name
, ".stab")) {
2583 if (0 == strcmp(sh_name
, ".stabstr")) {
2588 size
= sh
->sh_addralign
- 1;
2589 offset
= (offset
+ size
) & ~size
;
2590 if (sh
->sh_addralign
> s
->sh_addralign
)
2591 s
->sh_addralign
= sh
->sh_addralign
;
2592 s
->data_offset
= offset
;
2594 sm_table
[i
].offset
= offset
;
2596 /* concatenate sections */
2598 if (sh
->sh_type
!= SHT_NOBITS
) {
2600 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2601 ptr
= section_ptr_add(s
, size
);
2602 read(fd
, ptr
, size
);
2604 s
->data_offset
+= size
;
2609 /* gr relocate stab strings */
2610 if (stab_index
&& stabstr_index
) {
2613 s
= sm_table
[stab_index
].s
;
2614 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2615 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2616 o
= sm_table
[stabstr_index
].offset
;
2618 a
->n_strx
+= o
, a
++;
2621 /* second short pass to update sh_link and sh_info fields of new
2623 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2625 if (!s
|| !sm_table
[i
].new_section
)
2628 if (sh
->sh_link
> 0)
2629 s
->link
= sm_table
[sh
->sh_link
].s
;
2630 if (sh
->sh_type
== SHT_RELX
) {
2631 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2632 /* update backward link */
2633 s1
->sections
[s
->sh_info
]->reloc
= s
;
2638 /* resolve symbols */
2639 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2642 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2643 if (sym
->st_shndx
!= SHN_UNDEF
&&
2644 sym
->st_shndx
< SHN_LORESERVE
) {
2645 sm
= &sm_table
[sym
->st_shndx
];
2646 if (sm
->link_once
) {
2647 /* if a symbol is in a link once section, we use the
2648 already defined symbol. It is very important to get
2649 correct relocations */
2650 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2651 name
= (char *) strtab
+ sym
->st_name
;
2652 sym_index
= find_elf_sym(symtab_section
, name
);
2654 old_to_new_syms
[i
] = sym_index
;
2658 /* if no corresponding section added, no need to add symbol */
2661 /* convert section number */
2662 sym
->st_shndx
= sm
->s
->sh_num
;
2664 sym
->st_value
+= sm
->offset
;
2667 name
= (char *) strtab
+ sym
->st_name
;
2668 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2669 sym
->st_info
, sym
->st_other
,
2670 sym
->st_shndx
, name
);
2671 old_to_new_syms
[i
] = sym_index
;
2674 /* third pass to patch relocation entries */
2675 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2680 offset
= sm_table
[i
].offset
;
2681 switch(s
->sh_type
) {
2683 /* take relocation offset information */
2684 offseti
= sm_table
[sh
->sh_info
].offset
;
2685 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2688 /* convert symbol index */
2689 type
= ELFW(R_TYPE
)(rel
->r_info
);
2690 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2691 /* NOTE: only one symtab assumed */
2692 if (sym_index
>= nb_syms
)
2694 sym_index
= old_to_new_syms
[sym_index
];
2695 /* ignore link_once in rel section. */
2696 if (!sym_index
&& !sm
->link_once
2697 #ifdef TCC_TARGET_ARM
2698 && type
!= R_ARM_V4BX
2702 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2703 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2706 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2707 /* offset the relocation offset */
2708 rel
->r_offset
+= offseti
;
2709 #ifdef TCC_TARGET_ARM
2710 /* Jumps and branches from a Thumb code to a PLT entry need
2711 special handling since PLT entries are ARM code.
2712 Unconditional bl instructions referencing PLT entries are
2713 handled by converting these instructions into blx
2714 instructions. Other case of instructions referencing a PLT
2715 entry require to add a Thumb stub before the PLT entry to
2716 switch to ARM mode. We set bit plt_thumb_stub of the
2717 attribute of a symbol to indicate such a case. */
2718 if (type
== R_ARM_THM_JUMP24
)
2719 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2732 tcc_free(old_to_new_syms
);
2739 typedef struct ArchiveHeader
{
2740 char ar_name
[16]; /* name of this member */
2741 char ar_date
[12]; /* file mtime */
2742 char ar_uid
[6]; /* owner uid; printed as decimal */
2743 char ar_gid
[6]; /* owner gid; printed as decimal */
2744 char ar_mode
[8]; /* file mode, printed as octal */
2745 char ar_size
[10]; /* file size, printed as decimal */
2746 char ar_fmag
[2]; /* should contain ARFMAG */
2749 static int get_be32(const uint8_t *b
)
2751 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2754 /* load only the objects which resolve undefined symbols */
2755 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2757 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2759 const char *ar_names
, *p
;
2760 const uint8_t *ar_index
;
2763 data
= tcc_malloc(size
);
2764 if (read(fd
, data
, size
) != size
)
2766 nsyms
= get_be32(data
);
2767 ar_index
= data
+ 4;
2768 ar_names
= (char *) ar_index
+ nsyms
* 4;
2772 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2773 sym_index
= find_elf_sym(symtab_section
, p
);
2775 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2776 if(sym
->st_shndx
== SHN_UNDEF
) {
2777 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2779 lseek(fd
, off
, SEEK_SET
);
2780 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2795 /* load a '.a' file */
2796 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2803 unsigned long file_offset
;
2805 /* skip magic which was already checked */
2806 read(fd
, magic
, sizeof(magic
));
2809 len
= read(fd
, &hdr
, sizeof(hdr
));
2812 if (len
!= sizeof(hdr
)) {
2813 tcc_error_noabort("invalid archive");
2816 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2817 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2818 size
= strtol(ar_size
, NULL
, 0);
2819 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2820 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2821 if (ar_name
[i
] != ' ')
2824 ar_name
[i
+ 1] = '\0';
2825 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2827 size
= (size
+ 1) & ~1;
2828 if (!strcmp(ar_name
, "/")) {
2829 /* coff symbol table : we handle it */
2830 if(s1
->alacarte_link
)
2831 return tcc_load_alacarte(s1
, fd
, size
);
2832 } else if (!strcmp(ar_name
, "//") ||
2833 !strcmp(ar_name
, "__.SYMDEF") ||
2834 !strcmp(ar_name
, "__.SYMDEF/") ||
2835 !strcmp(ar_name
, "ARFILENAMES/")) {
2836 /* skip symbol table or archive names */
2838 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2841 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2846 #ifndef TCC_TARGET_PE
2847 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2848 is referenced by the user (so it should be added as DT_NEEDED in
2849 the generated ELF file) */
2850 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2853 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2854 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2855 ElfW(Sym
) *sym
, *dynsym
;
2856 ElfW(Dyn
) *dt
, *dynamic
;
2857 unsigned char *dynstr
;
2858 const char *name
, *soname
;
2859 DLLReference
*dllref
;
2861 read(fd
, &ehdr
, sizeof(ehdr
));
2863 /* test CPU specific stuff */
2864 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2865 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2866 tcc_error_noabort("bad architecture");
2871 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2873 /* load dynamic section and dynamic symbols */
2877 dynsym
= NULL
; /* avoid warning */
2878 dynstr
= NULL
; /* avoid warning */
2879 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2880 switch(sh
->sh_type
) {
2882 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2883 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2886 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2887 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2888 sh1
= &shdr
[sh
->sh_link
];
2889 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2896 /* compute the real library name */
2897 soname
= tcc_basename(filename
);
2899 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2900 if (dt
->d_tag
== DT_SONAME
) {
2901 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2905 /* if the dll is already loaded, do not load it */
2906 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2907 dllref
= s1
->loaded_dlls
[i
];
2908 if (!strcmp(soname
, dllref
->name
)) {
2909 /* but update level if needed */
2910 if (level
< dllref
->level
)
2911 dllref
->level
= level
;
2917 /* add the dll and its level */
2918 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2919 dllref
->level
= level
;
2920 strcpy(dllref
->name
, soname
);
2921 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2923 /* add dynamic symbols in dynsym_section */
2924 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2925 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2926 if (sym_bind
== STB_LOCAL
)
2928 name
= (char *) dynstr
+ sym
->st_name
;
2929 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
2930 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
2933 /* load all referenced DLLs */
2934 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2937 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
2938 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
2939 dllref
= s1
->loaded_dlls
[j
];
2940 if (!strcmp(name
, dllref
->name
))
2941 goto already_loaded
;
2943 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
2944 tcc_error_noabort("referenced dll '%s' not found", name
);
2961 #define LD_TOK_NAME 256
2962 #define LD_TOK_EOF (-1)
2964 /* return next ld script token */
2965 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
2983 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
2984 ch
= file
->buf_ptr
[0];
2992 /* case 'a' ... 'z': */
3019 /* case 'A' ... 'z': */
3054 if (!((ch
>= 'a' && ch
<= 'z') ||
3055 (ch
>= 'A' && ch
<= 'Z') ||
3056 (ch
>= '0' && ch
<= '9') ||
3057 strchr("/.-_+=$:\\,~", ch
)))
3059 if ((q
- name
) < name_size
- 1) {
3078 static int ld_add_file(TCCState
*s1
, const char filename
[])
3082 ret
= tcc_add_file_internal(s1
, filename
, 0);
3084 ret
= tcc_add_dll(s1
, filename
, 0);
3088 static inline int new_undef_syms(void)
3091 ret
= new_undef_sym
;
3096 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3098 char filename
[1024], libname
[1024];
3099 int t
, group
, nblibs
= 0, ret
= 0;
3102 group
= !strcmp(cmd
, "GROUP");
3105 t
= ld_next(s1
, filename
, sizeof(filename
));
3108 t
= ld_next(s1
, filename
, sizeof(filename
));
3111 if (t
== LD_TOK_EOF
) {
3112 tcc_error_noabort("unexpected end of file");
3114 goto lib_parse_error
;
3115 } else if (t
== ')') {
3117 } else if (t
== '-') {
3118 t
= ld_next(s1
, filename
, sizeof(filename
));
3119 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3120 tcc_error_noabort("library name expected");
3122 goto lib_parse_error
;
3124 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3125 if (s1
->static_link
) {
3126 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3128 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3130 } else if (t
!= LD_TOK_NAME
) {
3131 tcc_error_noabort("filename expected");
3133 goto lib_parse_error
;
3135 if (!strcmp(filename
, "AS_NEEDED")) {
3136 ret
= ld_add_file_list(s1
, cmd
, 1);
3138 goto lib_parse_error
;
3140 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3142 ret
= ld_add_file(s1
, filename
);
3144 goto lib_parse_error
;
3146 /* Add the filename *and* the libname to avoid future conversions */
3147 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3148 if (libname
[0] != '\0')
3149 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3153 t
= ld_next(s1
, filename
, sizeof(filename
));
3155 t
= ld_next(s1
, filename
, sizeof(filename
));
3158 if (group
&& !as_needed
) {
3159 while (new_undef_syms()) {
3162 for (i
= 0; i
< nblibs
; i
++)
3163 ld_add_file(s1
, libs
[i
]);
3167 dynarray_reset(&libs
, &nblibs
);
3171 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3173 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3176 char filename
[1024];
3179 ch
= file
->buf_ptr
[0];
3182 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3183 if (t
== LD_TOK_EOF
)
3185 else if (t
!= LD_TOK_NAME
)
3187 if (!strcmp(cmd
, "INPUT") ||
3188 !strcmp(cmd
, "GROUP")) {
3189 ret
= ld_add_file_list(s1
, cmd
, 0);
3192 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3193 !strcmp(cmd
, "TARGET")) {
3194 /* ignore some commands */
3195 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3199 t
= ld_next(s1
, filename
, sizeof(filename
));
3200 if (t
== LD_TOK_EOF
) {
3201 tcc_error_noabort("unexpected end of file");
3203 } else if (t
== ')') {
3213 #endif /* !TCC_TARGET_PE */