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ELF64: actually generate relative GOT/PLT references correctly
[nasm.git] / output / outelf64.c
blobf6dc617243dd6d59d47a46a670343cbb1a9414e1
1 /* outelf64.c output routines for the Netwide Assembler to produce
2 * ELF64 (x86_64 of course) object file format
3 *
4 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
5 * Julian Hall. All rights reserved. The software is
6 * redistributable under the license given in the file "LICENSE"
7 * distributed in the NASM archive.
8 */
9 #include "compiler.h"
10
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <ctype.h>
15 #include <inttypes.h>
16
17 #include "nasm.h"
18 #include "nasmlib.h"
19 #include "saa.h"
20 #include "raa.h"
21 #include "stdscan.h"
22 #include "outform.h"
23
24 /* Definitions in lieu of elf.h */
25 #define SHT_NULL 0 /* Inactive section header */
26 #define SHT_PROGBITS 1 /* Program defined content */
27 #define SHT_RELA 4 /* Relocation entries with addends */
28 #define SHT_NOBITS 8 /* Section requires no space in file */
29 #define SHF_WRITE (1 << 0) /* Writable */
30 #define SHF_ALLOC (1 << 1) /* Occupies memory during execution */
31 #define SHF_EXECINSTR (1 << 2) /* Executable */
32 #define SHN_ABS 0xfff1 /* Associated symbol is absolute */
33 #define SHN_COMMON 0xfff2 /* Associated symbol is common */
34 #define R_X86_64_NONE 0 /* No reloc */
35 #define R_X86_64_64 1 /* Direct 64 bit */
36 #define R_X86_64_PC32 2 /* PC relative 32 bit signed */
37 #define R_X86_64_GOT32 3 /* 32 bit GOT entry */
38 #define R_X86_64_PLT32 4 /* 32 bit PLT address */
39 #define R_X86_64_COPY 5 /* Copy symbol at runtime */
40 #define R_X86_64_GLOB_DAT 6 /* Create GOT entry */
41 #define R_X86_64_JUMP_SLOT 7 /* Create PLT entry */
42 #define R_X86_64_RELATIVE 8 /* Adjust by program base */
43 #define R_X86_64_GOTPCREL 9 /* 32 bit signed PC relative
44 offset to GOT */
45 #define R_X86_64_32 10 /* Direct 32 bit zero extended */
46 #define R_X86_64_32S 11 /* Direct 32 bit sign extended */
47 #define R_X86_64_16 12 /* Direct 16 bit zero extended */
48 #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */
49 #define R_X86_64_8 14 /* Direct 8 bit sign extended */
50 #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */
51 #define R_X86_64_DTPMOD64 16 /* ID of module containing symbol */
52 #define R_X86_64_DTPOFF64 17 /* Offset in module's TLS block */
53 #define R_X86_64_TPOFF64 18 /* Offset in initial TLS block */
54 #define R_X86_64_TLSGD 19 /* 32 bit signed PC relative offset
55 to two GOT entries for GD symbol */
56 #define R_X86_64_TLSLD 20 /* 32 bit signed PC relative offset
57 to two GOT entries for LD symbol */
58 #define R_X86_64_DTPOFF32 21 /* Offset in TLS block */
59 #define R_X86_64_GOTTPOFF 22 /* 32 bit signed PC relative offset
60 to GOT entry for IE symbol */
61 #define R_X86_64_TPOFF32 23 /* Offset in initial TLS block */
62 #define R_X86_64_PC64 24 /* word64 S + A - P */
63 #define R_X86_64_GOTOFF64 25 /* word64 S + A - GOT */
64 #define R_X86_64_GOTPC32 26 /* word32 GOT + A - P */
65 #define R_X86_64_GOT64 27 /* word64 G + A */
66 #define R_X86_64_GOTPCREL64 28 /* word64 G + GOT - P + A */
67 #define R_X86_64_GOTPC64 29 /* word64 GOT - P + A */
68 #define R_X86_64_GOTPLT64 30 /* word64 G + A */
69 #define R_X86_64_PLTOFF64 31 /* word64 L - GOT + A */
70 #define R_X86_64_SIZE32 32 /* word32 Z + A */
71 #define R_X86_64_SIZE64 33 /* word64 Z + A */
72 #define R_X86_64_GOTPC32_TLSDESC 34 /* word32 */
73 #define R_X86_64_TLSDESC_CALL 35 /* none */
74 #define R_X86_64_TLSDESC 36 /* word64×2 */
75 #define ET_REL 1 /* Relocatable file */
76 #define EM_X86_64 62 /* AMD x86-64 architecture */
77 #define STT_NOTYPE 0 /* Symbol type is unspecified */
78 #define STT_OBJECT 1 /* Symbol is a data object */
79 #define STT_FUNC 2 /* Symbol is a code object */
80 #define STT_SECTION 3 /* Symbol associated with a section */
81 #define STT_FILE 4 /* Symbol's name is file name */
82 #define STT_COMMON 5 /* Symbol is a common data object */
83 #define STT_TLS 6 /* Symbol is thread-local data object*/
84 #define STT_NUM 7 /* Number of defined types. */
85
86 /* Definitions in lieu of dwarf.h */
87 #define DW_TAG_compile_unit 0x11
88 #define DW_TAG_subprogram 0x2e
89 #define DW_AT_name 0x03
90 #define DW_AT_stmt_list 0x10
91 #define DW_AT_low_pc 0x11
92 #define DW_AT_high_pc 0x12
93 #define DW_AT_language 0x13
94 #define DW_AT_producer 0x25
95 #define DW_AT_frame_base 0x40
96 #define DW_FORM_addr 0x01
97 #define DW_FORM_data2 0x05
98 #define DW_FORM_data4 0x06
99 #define DW_FORM_string 0x08
100 #define DW_LNS_extended_op 0
101 #define DW_LNS_advance_pc 2
102 #define DW_LNS_advance_line 3
103 #define DW_LNS_set_file 4
104 #define DW_LNE_end_sequence 1
105 #define DW_LNE_set_address 2
106 #define DW_LNE_define_file 3
107 #define DW_LANG_Mips_Assembler 0x8001
108
109 #define SOC(ln,aa) ln - line_base + (line_range * aa) + opcode_base
110
111 typedef uint32_t Elf64_Word;
112 typedef uint64_t Elf64_Xword;
113 typedef uint64_t Elf64_Addr;
114 typedef uint64_t Elf64_Off;
115 typedef struct
116 {
117 Elf64_Word sh_name; /* Section name (string tbl index) */
118 Elf64_Word sh_type; /* Section type */
119 Elf64_Xword sh_flags; /* Section flags */
120 Elf64_Addr sh_addr; /* Section virtual addr at execution */
121 Elf64_Off sh_offset; /* Section file offset */
122 Elf64_Xword sh_size; /* Section size in bytes */
123 Elf64_Word sh_link; /* Link to another section */
124 Elf64_Word sh_info; /* Additional section information */
125 Elf64_Xword sh_addralign; /* Section alignment */
126 Elf64_Xword sh_entsize; /* Entry size if section holds table */
127 } Elf64_Shdr;
128
129
130 #ifdef OF_ELF64
131
132
133 struct Reloc {
134 struct Reloc *next;
135 int64_t address; /* relative to _start_ of section */
136 int64_t symbol; /* symbol index */
137 int64_t offset; /* symbol addend */
138 int type; /* type of relocation */
139 };
140
141 struct Symbol {
142 int32_t strpos; /* string table position of name */
143 int32_t section; /* section ID of the symbol */
144 int type; /* symbol type */
145 int other; /* symbol visibility */
146 int64_t value; /* address, or COMMON variable align */
147 int32_t size; /* size of symbol */
148 int32_t globnum; /* symbol table offset if global */
149 struct Symbol *next; /* list of globals in each section */
150 struct Symbol *nextfwd; /* list of unresolved-size symbols */
151 char *name; /* used temporarily if in above list */
152 };
153
154
155 struct Section {
156 struct SAA *data;
157 uint64_t len, size;
158 uint32_t nrelocs;
159 int32_t index; /* index into sects array */
160 uint32_t type; /* SHT_PROGBITS or SHT_NOBITS */
161 uint64_t align; /* alignment: power of two */
162 uint64_t flags; /* section flags */
163 char *name;
164 struct SAA *rel;
165 uint64_t rellen;
166 struct Reloc *head, **tail;
167 struct Symbol *gsyms; /* global symbols in section */
168 };
169
170 #define SECT_DELTA 32
171 static struct Section **sects;
172 static int nsects, sectlen;
173
174 #define SHSTR_DELTA 256
175 static char *shstrtab;
176 static int shstrtablen, shstrtabsize;
177
178 static struct SAA *syms;
179 static uint32_t nlocals, nglobs;
180
181 static int32_t def_seg;
182
183 static struct RAA *bsym;
184
185 static struct SAA *strs;
186 static uint32_t strslen;
187
188 static FILE *elffp;
189 static efunc error;
190 static evalfunc evaluate;
191
192 static struct Symbol *fwds;
193
194 static char elf_module[FILENAME_MAX];
195
196 static uint8_t elf_osabi = 0; /* Default OSABI = 0 (System V or Linux) */
197 static uint8_t elf_abiver = 0; /* Current ABI version */
198
199 extern struct ofmt of_elf64;
200
201 #define SHN_UNDEF 0
202
203 #define SYM_GLOBAL 0x10
204
205 #define STV_DEFAULT 0
206 #define STV_INTERNAL 1
207 #define STV_HIDDEN 2
208 #define STV_PROTECTED 3
209
210 #define GLOBAL_TEMP_BASE 1048576 /* bigger than any reasonable sym id */
211
212 #define SEG_ALIGN 16 /* alignment of sections in file */
213 #define SEG_ALIGN_1 (SEG_ALIGN-1)
214
215 #define TY_DEBUGSYMLIN 0x40 /* internal call to debug_out */
216
217 static const char align_str[SEG_ALIGN] = ""; /* ANSI will pad this with 0s */
218
219 static struct ELF_SECTDATA {
220 void *data;
221 int64_t len;
222 bool is_saa;
223 } *elf_sects;
224 static int elf_nsect, nsections;
225 static int64_t elf_foffs;
226
227 static void elf_write(void);
228 static void elf_sect_write(struct Section *, const void *, size_t);
229 static void elf_sect_writeaddr(struct Section *, int64_t, size_t);
230 static void elf_section_header(int, int, uint64_t, void *, bool, uint64_t, int, int,
231 int, int);
232 static void elf_write_sections(void);
233 static struct SAA *elf_build_symtab(int32_t *, int32_t *);
234 static struct SAA *elf_build_reltab(uint64_t *, struct Reloc *);
235 static void add_sectname(char *, char *);
236
237 /* type values for stabs debugging sections */
238 #define N_SO 0x64 /* ID for main source file */
239 #define N_SOL 0x84 /* ID for sub-source file */
240 #define N_BINCL 0x82 /* not currently used */
241 #define N_EINCL 0xA2 /* not currently used */
242 #define N_SLINE 0x44
243
244 struct stabentry {
245 uint32_t n_strx;
246 uint8_t n_type;
247 uint8_t n_other;
248 uint16_t n_desc;
249 uint32_t n_value;
250 };
251
252 struct erel {
253 int offset, info;
254 };
255
256 struct symlininfo {
257 int offset;
258 int section; /* index into sects[] */
259 int segto; /* internal section number */
260 char *name; /* shallow-copied pointer of section name */
261 };
262
263 struct linelist {
264 struct symlininfo info;
265 int line;
266 char *filename;
267 struct linelist *next;
268 struct linelist *last;
269 };
270
271 struct sectlist {
272 struct SAA *psaa;
273 int section;
274 int line;
275 int offset;
276 int file;
277 struct sectlist *next;
278 struct sectlist *last;
279 };
280
281 /* common debug variables */
282 static int currentline = 1;
283 static int debug_immcall = 0;
284
285 /* stabs debug variables */
286 static struct linelist *stabslines = 0;
287 static int numlinestabs = 0;
288 static char *stabs_filename = 0;
289 static int symtabsection;
290 static uint8_t *stabbuf = 0, *stabstrbuf = 0, *stabrelbuf = 0;
291 static int stablen, stabstrlen, stabrellen;
292
293 /* dwarf debug variables */
294 static struct linelist *dwarf_flist = 0, *dwarf_clist = 0, *dwarf_elist = 0;
295 static struct sectlist *dwarf_fsect = 0, *dwarf_csect = 0, *dwarf_esect = 0;
296 static int dwarf_numfiles = 0, dwarf_nsections;
297 static uint8_t *arangesbuf = 0, *arangesrelbuf = 0, *pubnamesbuf = 0, *infobuf = 0, *inforelbuf = 0,
298 *abbrevbuf = 0, *linebuf = 0, *linerelbuf = 0, *framebuf = 0, *locbuf = 0;
299 static int8_t line_base = -5, line_range = 14, opcode_base = 13;
300 static int arangeslen, arangesrellen, pubnameslen, infolen, inforellen,
301 abbrevlen, linelen, linerellen, framelen, loclen;
302 static int64_t dwarf_infosym, dwarf_abbrevsym, dwarf_linesym;
303
304
305 static struct dfmt df_dwarf;
306 static struct dfmt df_stabs;
307 static struct Symbol *lastsym;
308
309 /* common debugging routines */
310 void debug64_typevalue(int32_t);
311 void debug64_init(struct ofmt *, void *, FILE *, efunc);
312 void debug64_deflabel(char *, int32_t, int64_t, int, char *);
313 void debug64_directive(const char *, const char *);
314
315 /* stabs debugging routines */
316 void stabs64_linenum(const char *filename, int32_t linenumber, int32_t);
317 void stabs64_output(int, void *);
318 void stabs64_generate(void);
319 void stabs64_cleanup(void);
320
321 /* dwarf debugging routines */
322 void dwarf64_linenum(const char *filename, int32_t linenumber, int32_t);
323 void dwarf64_output(int, void *);
324 void dwarf64_generate(void);
325 void dwarf64_cleanup(void);
326 void dwarf64_findfile(const char *);
327 void dwarf64_findsect(const int);
328
329 /*
330 * Special section numbers which are used to define ELF special
331 * symbols, which can be used with WRT to provide PIC relocation
332 * types.
333 */
334 static int32_t elf_gotpc_sect, elf_gotoff_sect;
335 static int32_t elf_got_sect, elf_plt_sect;
336 static int32_t elf_sym_sect;
337
338 static void elf_init(FILE * fp, efunc errfunc, ldfunc ldef, evalfunc eval)
339 {
340 maxbits = 64;
341 elffp = fp;
342 error = errfunc;
343 evaluate = eval;
344 (void)ldef; /* placate optimisers */
345 sects = NULL;
346 nsects = sectlen = 0;
347 syms = saa_init((int32_t)sizeof(struct Symbol));
348 nlocals = nglobs = 0;
349 bsym = raa_init();
350 strs = saa_init(1L);
351 saa_wbytes(strs, "\0", 1L);
352 saa_wbytes(strs, elf_module, (int32_t)(strlen(elf_module) + 1));
353 strslen = 2 + strlen(elf_module);
354 shstrtab = NULL;
355 shstrtablen = shstrtabsize = 0;;
356 add_sectname("", "");
357
358 fwds = NULL;
359
360 elf_gotpc_sect = seg_alloc();
361 ldef("..gotpc", elf_gotpc_sect + 1, 0L, NULL, false, false, &of_elf64,
362 error);
363 elf_gotoff_sect = seg_alloc();
364 ldef("..gotoff", elf_gotoff_sect + 1, 0L, NULL, false, false, &of_elf64,
365 error);
366 elf_got_sect = seg_alloc();
367 ldef("..got", elf_got_sect + 1, 0L, NULL, false, false, &of_elf64,
368 error);
369 elf_plt_sect = seg_alloc();
370 ldef("..plt", elf_plt_sect + 1, 0L, NULL, false, false, &of_elf64,
371 error);
372 elf_sym_sect = seg_alloc();
373 ldef("..sym", elf_sym_sect + 1, 0L, NULL, false, false, &of_elf64,
374 error);
375
376 def_seg = seg_alloc();
377
378 }
379
380 static void elf_cleanup(int debuginfo)
381 {
382 struct Reloc *r;
383 int i;
384
385 (void)debuginfo;
386
387 elf_write();
388 fclose(elffp);
389 for (i = 0; i < nsects; i++) {
390 if (sects[i]->type != SHT_NOBITS)
391 saa_free(sects[i]->data);
392 if (sects[i]->head)
393 saa_free(sects[i]->rel);
394 while (sects[i]->head) {
395 r = sects[i]->head;
396 sects[i]->head = sects[i]->head->next;
397 nasm_free(r);
398 }
399 }
400 nasm_free(sects);
401 saa_free(syms);
402 raa_free(bsym);
403 saa_free(strs);
404 if (of_elf64.current_dfmt) {
405 of_elf64.current_dfmt->cleanup();
406 }
407 }
408 /* add entry to the elf .shstrtab section */
409 static void add_sectname(char *firsthalf, char *secondhalf)
410 {
411 int len = strlen(firsthalf) + strlen(secondhalf);
412 while (shstrtablen + len + 1 > shstrtabsize)
413 shstrtab = nasm_realloc(shstrtab, (shstrtabsize += SHSTR_DELTA));
414 strcpy(shstrtab + shstrtablen, firsthalf);
415 strcat(shstrtab + shstrtablen, secondhalf);
416 shstrtablen += len + 1;
417 }
418
419 static int elf_make_section(char *name, int type, int flags, int align)
420 {
421 struct Section *s;
422
423 s = nasm_malloc(sizeof(*s));
424
425 if (type != SHT_NOBITS)
426 s->data = saa_init(1L);
427 s->head = NULL;
428 s->tail = &s->head;
429 s->len = s->size = 0;
430 s->nrelocs = 0;
431 if (!strcmp(name, ".text"))
432 s->index = def_seg;
433 else
434 s->index = seg_alloc();
435 add_sectname("", name);
436 s->name = nasm_malloc(1 + strlen(name));
437 strcpy(s->name, name);
438 s->type = type;
439 s->flags = flags;
440 s->align = align;
441 s->gsyms = NULL;
442
443 if (nsects >= sectlen)
444 sects =
445 nasm_realloc(sects, (sectlen += SECT_DELTA) * sizeof(*sects));
446 sects[nsects++] = s;
447
448 return nsects - 1;
449 }
450
451 static int32_t elf_section_names(char *name, int pass, int *bits)
452 {
453 char *p;
454 unsigned flags_and, flags_or;
455 uint64_t type, align;
456 int i;
457
458 /*
459 * Default is 64 bits.
460 */
461 if (!name) {
462 *bits = 64;
463 return def_seg;
464 }
465
466 p = name;
467 while (*p && !nasm_isspace(*p))
468 p++;
469 if (*p)
470 *p++ = '\0';
471 flags_and = flags_or = type = align = 0;
472
473 while (*p && nasm_isspace(*p))
474 p++;
475 while (*p) {
476 char *q = p;
477 while (*p && !nasm_isspace(*p))
478 p++;
479 if (*p)
480 *p++ = '\0';
481 while (*p && nasm_isspace(*p))
482 p++;
483
484 if (!nasm_strnicmp(q, "align=", 6)) {
485 align = atoi(q + 6);
486 if (align == 0)
487 align = 1;
488 if ((align - 1) & align) { /* means it's not a power of two */
489 error(ERR_NONFATAL, "section alignment %d is not"
490 " a power of two", align);
491 align = 1;
492 }
493 } else if (!nasm_stricmp(q, "alloc")) {
494 flags_and |= SHF_ALLOC;
495 flags_or |= SHF_ALLOC;
496 } else if (!nasm_stricmp(q, "noalloc")) {
497 flags_and |= SHF_ALLOC;
498 flags_or &= ~SHF_ALLOC;
499 } else if (!nasm_stricmp(q, "exec")) {
500 flags_and |= SHF_EXECINSTR;
501 flags_or |= SHF_EXECINSTR;
502 } else if (!nasm_stricmp(q, "noexec")) {
503 flags_and |= SHF_EXECINSTR;
504 flags_or &= ~SHF_EXECINSTR;
505 } else if (!nasm_stricmp(q, "write")) {
506 flags_and |= SHF_WRITE;
507 flags_or |= SHF_WRITE;
508 } else if (!nasm_stricmp(q, "nowrite")) {
509 flags_and |= SHF_WRITE;
510 flags_or &= ~SHF_WRITE;
511 } else if (!nasm_stricmp(q, "progbits")) {
512 type = SHT_PROGBITS;
513 } else if (!nasm_stricmp(q, "nobits")) {
514 type = SHT_NOBITS;
515 }
516 }
517
518 if (!strcmp(name, ".comment") ||
519 !strcmp(name, ".shstrtab") ||
520 !strcmp(name, ".symtab") || !strcmp(name, ".strtab")) {
521 error(ERR_NONFATAL, "attempt to redefine reserved section"
522 "name `%s'", name);
523 return NO_SEG;
524 }
525
526 for (i = 0; i < nsects; i++)
527 if (!strcmp(name, sects[i]->name))
528 break;
529 if (i == nsects) {
530 if (!strcmp(name, ".text"))
531 i = elf_make_section(name, SHT_PROGBITS,
532 SHF_ALLOC | SHF_EXECINSTR, 16);
533 else if (!strcmp(name, ".rodata"))
534 i = elf_make_section(name, SHT_PROGBITS, SHF_ALLOC, 4);
535 else if (!strcmp(name, ".data"))
536 i = elf_make_section(name, SHT_PROGBITS,
537 SHF_ALLOC | SHF_WRITE, 4);
538 else if (!strcmp(name, ".bss"))
539 i = elf_make_section(name, SHT_NOBITS,
540 SHF_ALLOC | SHF_WRITE, 4);
541 else
542 i = elf_make_section(name, SHT_PROGBITS, SHF_ALLOC, 1);
543 if (type)
544 sects[i]->type = type;
545 if (align)
546 sects[i]->align = align;
547 sects[i]->flags &= ~flags_and;
548 sects[i]->flags |= flags_or;
549 } else if (pass == 1) {
550 if ((type && sects[i]->type != type)
551 || (align && sects[i]->align != align)
552 || (flags_and && ((sects[i]->flags & flags_and) != flags_or)))
553 error(ERR_WARNING, "incompatible section attributes ignored on"
554 " redeclaration of section `%s'", name);
555 }
556
557 return sects[i]->index;
558 }
559
560 static void elf_deflabel(char *name, int32_t segment, int64_t offset,
561 int is_global, char *special)
562 {
563 int pos = strslen;
564 struct Symbol *sym;
565 bool special_used = false;
566
567 #if defined(DEBUG) && DEBUG>2
568 fprintf(stderr,
569 " elf_deflabel: %s, seg=%x, off=%x, is_global=%d, %s\n",
570 name, segment, offset, is_global, special);
571 #endif
572 if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
573 /*
574 * This is a NASM special symbol. We never allow it into
575 * the ELF symbol table, even if it's a valid one. If it
576 * _isn't_ a valid one, we should barf immediately.
577 */
578 if (strcmp(name, "..gotpc") && strcmp(name, "..gotoff") &&
579 strcmp(name, "..got") && strcmp(name, "..plt") &&
580 strcmp(name, "..sym"))
581 error(ERR_NONFATAL, "unrecognised special symbol `%s'", name);
582 return;
583 }
584
585 if (is_global == 3) {
586 struct Symbol **s;
587 /*
588 * Fix up a forward-reference symbol size from the first
589 * pass.
590 */
591 for (s = &fwds; *s; s = &(*s)->nextfwd)
592 if (!strcmp((*s)->name, name)) {
593 struct tokenval tokval;
594 expr *e;
595 char *p = special;
596
597 while (*p && !nasm_isspace(*p))
598 p++;
599 while (*p && nasm_isspace(*p))
600 p++;
601 stdscan_reset();
602 stdscan_bufptr = p;
603 tokval.t_type = TOKEN_INVALID;
604 e = evaluate(stdscan, NULL, &tokval, NULL, 1, error, NULL);
605 if (e) {
606 if (!is_simple(e))
607 error(ERR_NONFATAL, "cannot use relocatable"
608 " expression as symbol size");
609 else
610 (*s)->size = reloc_value(e);
611 }
612
613 /*
614 * Remove it from the list of unresolved sizes.
615 */
616 nasm_free((*s)->name);
617 *s = (*s)->nextfwd;
618 return;
619 }
620 return; /* it wasn't an important one */
621 }
622
623 saa_wbytes(strs, name, (int32_t)(1 + strlen(name)));
624 strslen += 1 + strlen(name);
625
626 lastsym = sym = saa_wstruct(syms);
627
628 sym->strpos = pos;
629 sym->type = is_global ? SYM_GLOBAL : 0;
630 sym->other = STV_DEFAULT;
631 sym->size = 0;
632 if (segment == NO_SEG)
633 sym->section = SHN_ABS;
634 else {
635 int i;
636 sym->section = SHN_UNDEF;
637 if (nsects == 0 && segment == def_seg) {
638 int tempint;
639 if (segment != elf_section_names(".text", 2, &tempint))
640 error(ERR_PANIC,
641 "strange segment conditions in ELF driver");
642 sym->section = nsects;
643 } else {
644 for (i = 0; i < nsects; i++)
645 if (segment == sects[i]->index) {
646 sym->section = i + 1;
647 break;
648 }
649 }
650 }
651
652 if (is_global == 2) {
653 sym->size = offset;
654 sym->value = 0;
655 sym->section = SHN_COMMON;
656 /*
657 * We have a common variable. Check the special text to see
658 * if it's a valid number and power of two; if so, store it
659 * as the alignment for the common variable.
660 */
661 if (special) {
662 bool err;
663 sym->value = readnum(special, &err);
664 if (err)
665 error(ERR_NONFATAL, "alignment constraint `%s' is not a"
666 " valid number", special);
667 else if ((sym->value | (sym->value - 1)) != 2 * sym->value - 1)
668 error(ERR_NONFATAL, "alignment constraint `%s' is not a"
669 " power of two", special);
670 }
671 special_used = true;
672 } else
673 sym->value = (sym->section == SHN_UNDEF ? 0 : offset);
674
675 if (sym->type == SYM_GLOBAL) {
676 /*
677 * If sym->section == SHN_ABS, then the first line of the
678 * else section would cause a core dump, because its a reference
679 * beyond the end of the section array.
680 * This behaviour is exhibited by this code:
681 * GLOBAL crash_nasm
682 * crash_nasm equ 0
683 * To avoid such a crash, such requests are silently discarded.
684 * This may not be the best solution.
685 */
686 if (sym->section == SHN_UNDEF || sym->section == SHN_COMMON) {
687 bsym = raa_write(bsym, segment, nglobs);
688 } else if (sym->section != SHN_ABS) {
689 /*
690 * This is a global symbol; so we must add it to the linked
691 * list of global symbols in its section. We'll push it on
692 * the beginning of the list, because it doesn't matter
693 * much which end we put it on and it's easier like this.
694 *
695 * In addition, we check the special text for symbol
696 * type and size information.
697 */
698 sym->next = sects[sym->section - 1]->gsyms;
699 sects[sym->section - 1]->gsyms = sym;
700
701 if (special) {
702 int n = strcspn(special, " \t");
703
704 if (!nasm_strnicmp(special, "function", n))
705 sym->type |= STT_FUNC;
706 else if (!nasm_strnicmp(special, "data", n) ||
707 !nasm_strnicmp(special, "object", n))
708 sym->type |= STT_OBJECT;
709 else if (!nasm_strnicmp(special, "notype", n))
710 sym->type |= STT_NOTYPE;
711 else
712 error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
713 n, special);
714 special += n;
715
716 while (nasm_isspace(*special))
717 ++special;
718 if (*special) {
719 n = strcspn(special, " \t");
720 if (!nasm_strnicmp(special, "default", n))
721 sym->other = STV_DEFAULT;
722 else if (!nasm_strnicmp(special, "internal", n))
723 sym->other = STV_INTERNAL;
724 else if (!nasm_strnicmp(special, "hidden", n))
725 sym->other = STV_HIDDEN;
726 else if (!nasm_strnicmp(special, "protected", n))
727 sym->other = STV_PROTECTED;
728 else
729 n = 0;
730 special += n;
731 }
732
733 if (*special) {
734 struct tokenval tokval;
735 expr *e;
736 int fwd = 0;
737 char *saveme = stdscan_bufptr; /* bugfix? fbk 8/10/00 */
738
739 while (special[n] && nasm_isspace(special[n]))
740 n++;
741 /*
742 * We have a size expression; attempt to
743 * evaluate it.
744 */
745 stdscan_reset();
746 stdscan_bufptr = special + n;
747 tokval.t_type = TOKEN_INVALID;
748 e = evaluate(stdscan, NULL, &tokval, &fwd, 0, error,
749 NULL);
750 if (fwd) {
751 sym->nextfwd = fwds;
752 fwds = sym;
753 sym->name = nasm_strdup(name);
754 } else if (e) {
755 if (!is_simple(e))
756 error(ERR_NONFATAL, "cannot use relocatable"
757 " expression as symbol size");
758 else
759 sym->size = reloc_value(e);
760 }
761 stdscan_bufptr = saveme; /* bugfix? fbk 8/10/00 */
762 }
763 special_used = true;
764 }
765 }
766 sym->globnum = nglobs;
767 nglobs++;
768 } else
769 nlocals++;
770
771 if (special && !special_used)
772 error(ERR_NONFATAL, "no special symbol features supported here");
773 }
774
775 static void elf_add_reloc(struct Section *sect, int32_t segment,
776 int64_t offset, int type)
777 {
778 struct Reloc *r;
779 r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
780 sect->tail = &r->next;
781 r->next = NULL;
782
783 r->address = sect->len;
784 r->offset = offset;
785 if (segment == NO_SEG)
786 r->symbol = 0;
787 else {
788 int i;
789 r->symbol = 0;
790 for (i = 0; i < nsects; i++)
791 if (segment == sects[i]->index)
792 r->symbol = i + 2;
793 if (!r->symbol)
794 r->symbol = GLOBAL_TEMP_BASE + raa_read(bsym, segment);
795 }
796 r->type = type;
797
798 sect->nrelocs++;
799 }
800
801 /*
802 * This routine deals with ..got and ..sym relocations: the more
803 * complicated kinds. In shared-library writing, some relocations
804 * with respect to global symbols must refer to the precise symbol
805 * rather than referring to an offset from the base of the section
806 * _containing_ the symbol. Such relocations call to this routine,
807 * which searches the symbol list for the symbol in question.
808 *
809 * R_386_GOT32 references require the _exact_ symbol address to be
810 * used; R_386_32 references can be at an offset from the symbol.
811 * The boolean argument `exact' tells us this.
812 *
813 * Return value is the adjusted value of `addr', having become an
814 * offset from the symbol rather than the section. Should always be
815 * zero when returning from an exact call.
816 *
817 * Limitation: if you define two symbols at the same place,
818 * confusion will occur.
819 *
820 * Inefficiency: we search, currently, using a linked list which
821 * isn't even necessarily sorted.
822 */
823 static void elf_add_gsym_reloc(struct Section *sect,
824 int32_t segment, int64_t offset, int64_t pcrel,
825 int type, bool exact)
826 {
827 struct Reloc *r;
828 struct Section *s;
829 struct Symbol *sym, *sm;
830 int i;
831
832 /*
833 * First look up the segment/offset pair and find a global
834 * symbol corresponding to it. If it's not one of our segments,
835 * then it must be an external symbol, in which case we're fine
836 * doing a normal elf_add_reloc after first sanity-checking
837 * that the offset from the symbol is zero.
838 */
839 s = NULL;
840 for (i = 0; i < nsects; i++)
841 if (segment == sects[i]->index) {
842 s = sects[i];
843 break;
844 }
845
846 if (!s) {
847 if (exact && offset)
848 error(ERR_NONFATAL, "invalid access to an external symbol");
849 else
850 elf_add_reloc(sect, segment, offset - pcrel, type);
851 return;
852 }
853
854 if (exact) {
855 /*
856 * Find a symbol pointing _exactly_ at this one.
857 */
858 for (sym = s->gsyms; sym; sym = sym->next)
859 if (sym->value == offset)
860 break;
861 if (!sym) {
862 error(ERR_NONFATAL, "unable to find a suitable global symbol"
863 " for this reference");
864 return;
865 }
866 } else {
867 /*
868 * Find the nearest symbol below this one.
869 */
870 sym = NULL;
871 for (sm = s->gsyms; sm; sm = sm->next)
872 if (sm->value <= offset && (!sym || sm->value > sym->value))
873 sym = sm;
874 }
875
876 r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
877 sect->tail = &r->next;
878 r->next = NULL;
879
880 r->address = sect->len;
881 r->offset = offset - pcrel - sym->value;
882 r->symbol = GLOBAL_TEMP_BASE + sym->globnum;
883 r->type = type;
884
885 sect->nrelocs++;
886 }
887
888 static void elf_out(int32_t segto, const void *data,
889 enum out_type type, uint64_t size,
890 int32_t segment, int32_t wrt)
891 {
892 struct Section *s;
893 int64_t addr, zero;
894 int i;
895 static struct symlininfo sinfo;
896
897 zero = 0;
898
899 #if defined(DEBUG) && DEBUG>2
900 if (data) fprintf(stderr,
901 " elf_out line: %d type: %x seg: %d segto: %d bytes: %x data: %"PRIx64"\n",
902 currentline, type, segment, segto, size, *(int64_t *)data);
903 else fprintf(stderr,
904 " elf_out line: %d type: %x seg: %d segto: %d bytes: %x\n",
905 currentline, type, segment, segto, size);
906 #endif
907
908 /*
909 * handle absolute-assembly (structure definitions)
910 */
911 if (segto == NO_SEG) {
912 if (type != OUT_RESERVE)
913 error(ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
914 " space");
915 return;
916 }
917
918 s = NULL;
919 for (i = 0; i < nsects; i++)
920 if (segto == sects[i]->index) {
921 s = sects[i];
922 break;
923 }
924 if (!s) {
925 int tempint; /* ignored */
926 if (segto != elf_section_names(".text", 2, &tempint))
927 error(ERR_PANIC, "strange segment conditions in ELF driver");
928 else {
929 s = sects[nsects - 1];
930 i = nsects - 1;
931 }
932 }
933 /* invoke current debug_output routine */
934 if (of_elf64.current_dfmt) {
935 sinfo.offset = s->len;
936 sinfo.section = i;
937 sinfo.segto = segto;
938 sinfo.name = s->name;
939 of_elf64.current_dfmt->debug_output(TY_DEBUGSYMLIN, &sinfo);
940 }
941 /* end of debugging stuff */
942
943 if (s->type == SHT_NOBITS && type != OUT_RESERVE) {
944 error(ERR_WARNING, "attempt to initialize memory in"
945 " BSS section `%s': ignored", s->name);
946 switch (type) {
947 case OUT_REL2ADR:
948 size = 2;
949 break;
950 case OUT_REL4ADR:
951 size = 4;
952 break;
953 case OUT_REL8ADR:
954 size = 8;
955 break;
956 default:
957 break; /* size is already set */
958 }
959 s->len += size;
960 return;
961 }
962
963 if (type == OUT_RESERVE) {
964 if (s->type == SHT_PROGBITS) {
965 error(ERR_WARNING, "uninitialized space declared in"
966 " non-BSS section `%s': zeroing", s->name);
967 elf_sect_write(s, NULL, size);
968 } else
969 s->len += size;
970 } else if (type == OUT_RAWDATA) {
971 if (segment != NO_SEG)
972 error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
973 elf_sect_write(s, data, size);
974 } else if (type == OUT_ADDRESS) {
975 addr = *(int64_t *)data;
976 if (segment == NO_SEG) {
977 /* Do nothing */
978 } else if (segment % 2) {
979 error(ERR_NONFATAL, "ELF format does not support"
980 " segment base references");
981 } else {
982 if (wrt == NO_SEG) {
983 switch ((int)size) {
984 case 1:
985 elf_add_reloc(s, segment, addr, R_X86_64_8);
986 break;
987 case 2:
988 elf_add_reloc(s, segment, addr, R_X86_64_16);
989 break;
990 case 4:
991 elf_add_reloc(s, segment, addr, R_X86_64_32);
992 break;
993 case 8:
994 elf_add_reloc(s, segment, addr, R_X86_64_64);
995 break;
996 default:
997 error(ERR_PANIC, "internal error elf64-hpa-871");
998 break;
999 }
1000 addr = 0;
1001 } else if (wrt == elf_gotpc_sect + 1) {
1002 /*
1003 * The user will supply GOT relative to $$. ELF
1004 * will let us have GOT relative to $. So we
1005 * need to fix up the data item by $-$$.
1006 */
1007 addr += s->len;
1008 elf_add_reloc(s, segment, addr, R_X86_64_GOTPC32);
1009 addr = 0;
1010 } else if (wrt == elf_gotoff_sect + 1) {
1011 if (size != 8) {
1012 error(ERR_NONFATAL, "ELF64 requires ..gotoff "
1013 "references to be qword absolute");
1014 } else {
1015 elf_add_reloc(s, segment, addr, R_X86_64_GOTOFF64);
1016 addr = 0;
1017 }
1018 } else if (wrt == elf_got_sect + 1) {
1019 switch ((int)size) {
1020 case 4:
1021 elf_add_gsym_reloc(s, segment, addr, 0,
1022 R_X86_64_GOT32, true);
1023 addr = 0;
1024 break;
1025 case 8:
1026 elf_add_gsym_reloc(s, segment, addr, 0,
1027 R_X86_64_GOT64, true);
1028 addr = 0;
1029 break;
1030 default:
1031 error(ERR_NONFATAL, "invalid ..got reference");
1032 break;
1033 }
1034 } else if (wrt == elf_sym_sect + 1) {
1035 switch ((int)size) {
1036 case 1:
1037 elf_add_gsym_reloc(s, segment, addr, 0,
1038 R_X86_64_8, false);
1039 addr = 0;
1040 break;
1041 case 2:
1042 elf_add_gsym_reloc(s, segment, addr, 0,
1043 R_X86_64_16, false);
1044 addr = 0;
1045 break;
1046 case 4:
1047 elf_add_gsym_reloc(s, segment, addr, 0,
1048 R_X86_64_32, false);
1049 addr = 0;
1050 break;
1051 case 8:
1052 elf_add_gsym_reloc(s, segment, addr, 0,
1053 R_X86_64_64, false);
1054 addr = 0;
1055 break;
1056 default:
1057 error(ERR_PANIC, "internal error elf64-hpa-903");
1058 break;
1059 }
1060 } else if (wrt == elf_plt_sect + 1) {
1061 error(ERR_NONFATAL, "ELF format cannot produce non-PC-"
1062 "relative PLT references");
1063 } else {
1064 error(ERR_NONFATAL, "ELF format does not support this"
1065 " use of WRT");
1066 }
1067 }
1068 elf_sect_writeaddr(s, addr, size);
1069 } else if (type == OUT_REL2ADR) {
1070 addr = *(int64_t *)data;
1071 if (segment == segto)
1072 error(ERR_PANIC, "intra-segment OUT_REL2ADR");
1073 if (segment == NO_SEG) {
1074 /* Do nothing */
1075 } else if (segment % 2) {
1076 error(ERR_NONFATAL, "ELF format does not support"
1077 " segment base references");
1078 } else {
1079 if (wrt == NO_SEG) {
1080 elf_add_reloc(s, segment, addr-size, R_X86_64_PC16);
1081 addr = 0;
1082 } else {
1083 error(ERR_NONFATAL,
1084 "Unsupported non-32-bit ELF relocation [2]");
1085 }
1086 }
1087 elf_sect_writeaddr(s, addr, size);
1088 } else if (type == OUT_REL4ADR) {
1089 addr = *(int64_t *)data;
1090 if (segment == segto)
1091 error(ERR_PANIC, "intra-segment OUT_REL4ADR");
1092 if (segment == NO_SEG) {
1093 /* Do nothing */
1094 } else if (segment % 2) {
1095 error(ERR_NONFATAL, "ELF64 format does not support"
1096 " segment base references");
1097 } else {
1098 if (wrt == NO_SEG) {
1099 elf_add_reloc(s, segment, addr-size, R_X86_64_PC32);
1100 addr = 0;
1101 } else if (wrt == elf_plt_sect + 1) {
1102 elf_add_gsym_reloc(s, segment, addr, size,
1103 R_X86_64_PLT32, false);
1104 addr = 0;
1105 } else if (wrt == elf_gotpc_sect + 1 ||
1106 wrt == elf_got_sect + 1) {
1107 printf("addr = %ld, pcrel = %ld\n", addr, size);
1108 elf_add_gsym_reloc(s, segment, addr, size,
1109 R_X86_64_GOTPCREL, false);
1110 addr = 0;
1111 } else if (wrt == elf_gotoff_sect + 1 ||
1112 wrt == elf_got_sect + 1) {
1113 error(ERR_NONFATAL, "ELF64 requires ..gotoff references to be "
1114 "qword absolute");
1115 } else {
1116 error(ERR_NONFATAL, "ELF64 format does not support this"
1117 " use of WRT");
1118 }
1119 }
1120 elf_sect_writeaddr(s, addr, size);
1121 } else if (type == OUT_REL8ADR) {
1122 addr = *(int64_t *)data;
1123 if (segment == segto)
1124 error(ERR_PANIC, "intra-segment OUT_REL8ADR");
1125 if (segment == NO_SEG) {
1126 /* Do nothing */
1127 } else if (segment % 2) {
1128 error(ERR_NONFATAL, "ELF64 format does not support"
1129 " segment base references");
1130 } else {
1131 if (wrt == NO_SEG) {
1132 elf_add_reloc(s, segment, addr-size, R_X86_64_PC64);
1133 addr = 0;
1134 } else if (wrt == elf_gotpc_sect + 1 ||
1135 wrt == elf_got_sect + 1) {
1136 elf_add_gsym_reloc(s, segment, addr, size,
1137 R_X86_64_GOTPCREL64, false);
1138 addr = 0;
1139 } else if (wrt == elf_gotoff_sect + 1 ||
1140 wrt == elf_got_sect + 1) {
1141 error(ERR_NONFATAL, "ELF64 requires ..gotoff references to be "
1142 "qword absolute");
1143 } else {
1144 error(ERR_NONFATAL, "ELF64 format does not support this"
1145 " use of WRT");
1146 }
1147 }
1148 elf_sect_writeaddr(s, addr, size);
1149 }
1150 }
1151
1152 static void elf_write(void)
1153 {
1154 int align;
1155 int scount;
1156 char *p;
1157 int commlen;
1158 char comment[64];
1159 int i;
1160
1161 struct SAA *symtab;
1162 int32_t symtablen, symtablocal;
1163
1164 /*
1165 * Work out how many sections we will have. We have SHN_UNDEF,
1166 * then the flexible user sections, then the four fixed
1167 * sections `.comment', `.shstrtab', `.symtab' and `.strtab',
1168 * then optionally relocation sections for the user sections.
1169 */
1170 if (of_elf64.current_dfmt == &df_stabs)
1171 nsections = 8;
1172 else if (of_elf64.current_dfmt == &df_dwarf)
1173 nsections = 15;
1174 else
1175 nsections = 5; /* SHN_UNDEF and the fixed ones */
1176
1177 add_sectname("", ".comment");
1178 add_sectname("", ".shstrtab");
1179 add_sectname("", ".symtab");
1180 add_sectname("", ".strtab");
1181 for (i = 0; i < nsects; i++) {
1182 nsections++; /* for the section itself */
1183 if (sects[i]->head) {
1184 nsections++; /* for its relocations */
1185 add_sectname(".rela", sects[i]->name);
1186 }
1187 }
1188
1189 if (of_elf64.current_dfmt == &df_stabs) {
1190 /* in case the debug information is wanted, just add these three sections... */
1191 add_sectname("", ".stab");
1192 add_sectname("", ".stabstr");
1193 add_sectname(".rel", ".stab");
1194 }
1195
1196 else if (of_elf64.current_dfmt == &df_dwarf) {
1197 /* the dwarf debug standard specifies the following ten sections,
1198 not all of which are currently implemented,
1199 although all of them are defined. */
1200 #define debug_aranges (int64_t) (nsections-10)
1201 #define debug_info (int64_t) (nsections-7)
1202 #define debug_abbrev (int64_t) (nsections-5)
1203 #define debug_line (int64_t) (nsections-4)
1204 add_sectname("", ".debug_aranges");
1205 add_sectname(".rela", ".debug_aranges");
1206 add_sectname("", ".debug_pubnames");
1207 add_sectname("", ".debug_info");
1208 add_sectname(".rela", ".debug_info");
1209 add_sectname("", ".debug_abbrev");
1210 add_sectname("", ".debug_line");
1211 add_sectname(".rela", ".debug_line");
1212 add_sectname("", ".debug_frame");
1213 add_sectname("", ".debug_loc");
1214 }
1215
1216 /*
1217 * Do the comment.
1218 */
1219 *comment = '\0';
1220 commlen =
1221 2 + sprintf(comment + 1, "The Netwide Assembler %s", NASM_VER);
1222
1223 /*
1224 * Output the ELF header.
1225 */
1226 fwrite("\177ELF\2\1\1", 7, 1, elffp);
1227 fputc(elf_osabi, elffp);
1228 fputc(elf_abiver, elffp);
1229 fwrite("\0\0\0\0\0\0\0", 7, 1, elffp);
1230 fwriteint16_t(ET_REL, elffp); /* relocatable file */
1231 fwriteint16_t(EM_X86_64, elffp); /* processor ID */
1232 fwriteint32_t(1L, elffp); /* EV_CURRENT file format version */
1233 fwriteint64_t(0L, elffp); /* no entry point */
1234 fwriteint64_t(0L, elffp); /* no program header table */
1235 fwriteint64_t(0x40L, elffp); /* section headers straight after
1236 * ELF header plus alignment */
1237 fwriteint32_t(0L, elffp); /* 386 defines no special flags */
1238 fwriteint16_t(0x40, elffp); /* size of ELF header */
1239 fwriteint16_t(0, elffp); /* no program header table, again */
1240 fwriteint16_t(0, elffp); /* still no program header table */
1241 fwriteint16_t(sizeof(Elf64_Shdr), elffp); /* size of section header */
1242 fwriteint16_t(nsections, elffp); /* number of sections */
1243 fwriteint16_t(nsects + 2, elffp); /* string table section index for
1244 * section header table */
1245
1246 /*
1247 * Build the symbol table and relocation tables.
1248 */
1249 symtab = elf_build_symtab(&symtablen, &symtablocal);
1250 for (i = 0; i < nsects; i++)
1251 if (sects[i]->head)
1252 sects[i]->rel = elf_build_reltab(&sects[i]->rellen,
1253 sects[i]->head);
1254
1255 /*
1256 * Now output the section header table.
1257 */
1258
1259 elf_foffs = 0x40 + sizeof(Elf64_Shdr) * nsections;
1260 align = ((elf_foffs + SEG_ALIGN_1) & ~SEG_ALIGN_1) - elf_foffs;
1261 elf_foffs += align;
1262 elf_nsect = 0;
1263 elf_sects = nasm_malloc(sizeof(*elf_sects) * nsections);
1264 elf_section_header(0, 0, 0, NULL, false, 0L, 0, 0, 0, 0); /* SHN_UNDEF */
1265 scount = 1; /* needed for the stabs debugging to track the symtable section */
1266 p = shstrtab + 1;
1267 for (i = 0; i < nsects; i++) {
1268 elf_section_header(p - shstrtab, sects[i]->type, sects[i]->flags,
1269 (sects[i]->type == SHT_PROGBITS ?
1270 sects[i]->data : NULL), true,
1271 sects[i]->len, 0, 0, sects[i]->align, 0);
1272 p += strlen(p) + 1;
1273 scount++; /* ditto */
1274 }
1275 elf_section_header(p - shstrtab, 1, 0, comment, false, (int32_t)commlen, 0, 0, 1, 0); /* .comment */
1276 scount++; /* ditto */
1277 p += strlen(p) + 1;
1278 elf_section_header(p - shstrtab, 3, 0, shstrtab, false, (int32_t)shstrtablen, 0, 0, 1, 0); /* .shstrtab */
1279 scount++; /* ditto */
1280 p += strlen(p) + 1;
1281 elf_section_header(p - shstrtab, 2, 0, symtab, true, symtablen, nsects + 4, symtablocal, 4, 24); /* .symtab */
1282 symtabsection = scount; /* now we got the symtab section index in the ELF file */
1283 p += strlen(p) + 1;
1284 elf_section_header(p - shstrtab, 3, 0, strs, true, strslen, 0, 0, 1, 0); /* .strtab */
1285 for (i = 0; i < nsects; i++)
1286 if (sects[i]->head) {
1287 p += strlen(p) + 1;
1288 elf_section_header(p - shstrtab,SHT_RELA, 0, sects[i]->rel, true,
1289 sects[i]->rellen, nsects + 3, i + 1, 4, 24);
1290 }
1291 if (of_elf64.current_dfmt == &df_stabs) {
1292 /* for debugging information, create the last three sections
1293 which are the .stab , .stabstr and .rel.stab sections respectively */
1294
1295 /* this function call creates the stab sections in memory */
1296 stabs64_generate();
1297
1298 if ((stabbuf) && (stabstrbuf) && (stabrelbuf)) {
1299 p += strlen(p) + 1;
1300 elf_section_header(p - shstrtab, 1, 0, stabbuf, false, stablen,
1301 nsections - 2, 0, 4, 12);
1302
1303 p += strlen(p) + 1;
1304 elf_section_header(p - shstrtab, 3, 0, stabstrbuf, false,
1305 stabstrlen, 0, 0, 4, 0);
1306
1307 p += strlen(p) + 1;
1308 /* link -> symtable info -> section to refer to */
1309 elf_section_header(p - shstrtab, 9, 0, stabrelbuf, false,
1310 stabrellen, symtabsection, nsections - 3, 4,
1311 16);
1312 }
1313 }
1314 else if (of_elf64.current_dfmt == &df_dwarf) {
1315 /* for dwarf debugging information, create the ten dwarf sections */
1316
1317 /* this function call creates the dwarf sections in memory */
1318 if (dwarf_fsect) dwarf64_generate();
1319
1320 p += strlen(p) + 1;
1321 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, arangesbuf, false,
1322 arangeslen, 0, 0, 1, 0);
1323 p += strlen(p) + 1;
1324 elf_section_header(p - shstrtab, SHT_RELA, 0, arangesrelbuf, false,
1325 arangesrellen, symtabsection, debug_aranges, 1, 24);
1326 p += strlen(p) + 1;
1327 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, pubnamesbuf, false,
1328 pubnameslen, 0, 0, 1, 0);
1329 p += strlen(p) + 1;
1330 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, infobuf, false,
1331 infolen, 0, 0, 1, 0);
1332 p += strlen(p) + 1;
1333 elf_section_header(p - shstrtab, SHT_RELA, 0, inforelbuf, false,
1334 inforellen, symtabsection, debug_info, 1, 24);
1335 p += strlen(p) + 1;
1336 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, abbrevbuf, false,
1337 abbrevlen, 0, 0, 1, 0);
1338 p += strlen(p) + 1;
1339 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, linebuf, false,
1340 linelen, 0, 0, 1, 0);
1341 p += strlen(p) + 1;
1342 elf_section_header(p - shstrtab, SHT_RELA, 0, linerelbuf, false,
1343 linerellen, symtabsection, debug_line, 1, 24);
1344 p += strlen(p) + 1;
1345 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, framebuf, false,
1346 framelen, 0, 0, 8, 0);
1347 p += strlen(p) + 1;
1348 elf_section_header(p - shstrtab, SHT_PROGBITS, 0, locbuf, false,
1349 loclen, 0, 0, 1, 0);
1350
1351 }
1352 fwrite(align_str, align, 1, elffp);
1353
1354 /*
1355 * Now output the sections.
1356 */
1357 elf_write_sections();
1358
1359 nasm_free(elf_sects);
1360 saa_free(symtab);
1361 }
1362
1363 static struct SAA *elf_build_symtab(int32_t *len, int32_t *local)
1364 {
1365 struct SAA *s = saa_init(1L);
1366 struct Symbol *sym;
1367 uint8_t entry[24], *p;
1368 int i;
1369
1370 *len = *local = 0;
1371
1372 /*
1373 * First, an all-zeros entry, required by the ELF spec.
1374 */
1375 saa_wbytes(s, NULL, 24L); /* null symbol table entry */
1376 *len += 24;
1377 (*local)++;
1378
1379 /*
1380 * Next, an entry for the file name.
1381 */
1382 p = entry;
1383 WRITELONG(p, 1); /* we know it's 1st entry in strtab */
1384 WRITESHORT(p, STT_FILE); /* type FILE */
1385 WRITESHORT(p, SHN_ABS);
1386 WRITEDLONG(p, (uint64_t) 0); /* no value */
1387 WRITEDLONG(p, (uint64_t) 0); /* no size either */
1388 saa_wbytes(s, entry, 24L);
1389 *len += 24;
1390 (*local)++;
1391
1392 /*
1393 * Now some standard symbols defining the segments, for relocation
1394 * purposes.
1395 */
1396 for (i = 1; i <= nsects; i++) {
1397 p = entry;
1398 WRITELONG(p, 0); /* no symbol name */
1399 WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
1400 WRITESHORT(p, i); /* section id */
1401 WRITEDLONG(p, (uint64_t) 0); /* offset zero */
1402 WRITEDLONG(p, (uint64_t) 0); /* size zero */
1403 saa_wbytes(s, entry, 24L);
1404 *len += 24;
1405 (*local)++;
1406 }
1407
1408
1409 /*
1410 * Now the other local symbols.
1411 */
1412 saa_rewind(syms);
1413 while ((sym = saa_rstruct(syms))) {
1414 if (sym->type & SYM_GLOBAL)
1415 continue;
1416 p = entry;
1417 WRITELONG(p, sym->strpos); /* index into symbol string table */
1418 WRITECHAR(p, sym->type); /* type and binding */
1419 WRITECHAR(p, sym->other); /* visibility */
1420 WRITESHORT(p, sym->section); /* index into section header table */
1421 WRITEDLONG(p, (int64_t)sym->value); /* value of symbol */
1422 WRITEDLONG(p, (int64_t)sym->size); /* size of symbol */
1423 saa_wbytes(s, entry, 24L);
1424 *len += 24;
1425 (*local)++;
1426 }
1427 /*
1428 * dwarf needs symbols for debug sections
1429 * which are relocation targets.
1430 */
1431 if (of_elf64.current_dfmt == &df_dwarf) {
1432 dwarf_infosym = *local;
1433 p = entry;
1434 WRITELONG(p, 0); /* no symbol name */
1435 WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
1436 WRITESHORT(p, debug_info); /* section id */
1437 WRITEDLONG(p, (uint64_t) 0); /* offset zero */
1438 WRITEDLONG(p, (uint64_t) 0); /* size zero */
1439 saa_wbytes(s, entry, 24L);
1440 *len += 24;
1441 (*local)++;
1442 dwarf_abbrevsym = *local;
1443 p = entry;
1444 WRITELONG(p, 0); /* no symbol name */
1445 WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
1446 WRITESHORT(p, debug_abbrev); /* section id */
1447 WRITEDLONG(p, (uint64_t) 0); /* offset zero */
1448 WRITEDLONG(p, (uint64_t) 0); /* size zero */
1449 saa_wbytes(s, entry, 24L);
1450 *len += 24;
1451 (*local)++;
1452 dwarf_linesym = *local;
1453 p = entry;
1454 WRITELONG(p, 0); /* no symbol name */
1455 WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
1456 WRITESHORT(p, debug_line); /* section id */
1457 WRITEDLONG(p, (uint64_t) 0); /* offset zero */
1458 WRITEDLONG(p, (uint64_t) 0); /* size zero */
1459 saa_wbytes(s, entry, 24L);
1460 *len += 24;
1461 (*local)++;
1462 }
1463
1464 /*
1465 * Now the global symbols.
1466 */
1467 saa_rewind(syms);
1468 while ((sym = saa_rstruct(syms))) {
1469 if (!(sym->type & SYM_GLOBAL))
1470 continue;
1471 p = entry;
1472 WRITELONG(p, sym->strpos);
1473 WRITECHAR(p, sym->type); /* type and binding */
1474 WRITECHAR(p, sym->other); /* visibility */
1475 WRITESHORT(p, sym->section);
1476 WRITEDLONG(p, (int64_t)sym->value);
1477 WRITEDLONG(p, (int64_t)sym->size);
1478 saa_wbytes(s, entry, 24L);
1479 *len += 24;
1480 }
1481
1482 return s;
1483 }
1484
1485 static struct SAA *elf_build_reltab(uint64_t *len, struct Reloc *r)
1486 {
1487 struct SAA *s;
1488 uint8_t *p, entry[24];
1489
1490 if (!r)
1491 return NULL;
1492
1493 s = saa_init(1L);
1494 *len = 0;
1495
1496 while (r) {
1497 int64_t sym = r->symbol;
1498
1499 if (sym >= GLOBAL_TEMP_BASE)
1500 {
1501 if (of_elf64.current_dfmt == &df_dwarf)
1502 sym += -GLOBAL_TEMP_BASE + (nsects + 5) + nlocals;
1503 else sym += -GLOBAL_TEMP_BASE + (nsects + 2) + nlocals;
1504 }
1505 p = entry;
1506 WRITEDLONG(p, r->address);
1507 WRITEDLONG(p, (sym << 32) + r->type);
1508 WRITEDLONG(p, r->offset);
1509 saa_wbytes(s, entry, 24L);
1510 *len += 24;
1511
1512 r = r->next;
1513 }
1514
1515 return s;
1516 }
1517
1518 static void elf_section_header(int name, int type, uint64_t flags,
1519 void *data, bool is_saa, uint64_t datalen,
1520 int link, int info, int align, int eltsize)
1521 {
1522 elf_sects[elf_nsect].data = data;
1523 elf_sects[elf_nsect].len = datalen;
1524 elf_sects[elf_nsect].is_saa = is_saa;
1525 elf_nsect++;
1526
1527 fwriteint32_t((int32_t)name, elffp);
1528 fwriteint32_t((int32_t)type, elffp);
1529 fwriteint64_t((int64_t)flags, elffp);
1530 fwriteint64_t(0L, elffp); /* no address, ever, in object files */
1531 fwriteint64_t(type == 0 ? 0L : elf_foffs, elffp);
1532 fwriteint64_t(datalen, elffp);
1533 if (data)
1534 elf_foffs += (datalen + SEG_ALIGN_1) & ~SEG_ALIGN_1;
1535 fwriteint32_t((int32_t)link, elffp);
1536 fwriteint32_t((int32_t)info, elffp);
1537 fwriteint64_t((int64_t)align, elffp);
1538 fwriteint64_t((int64_t)eltsize, elffp);
1539 }
1540
1541 static void elf_write_sections(void)
1542 {
1543 int i;
1544 for (i = 0; i < elf_nsect; i++)
1545 if (elf_sects[i].data) {
1546 int32_t len = elf_sects[i].len;
1547 int32_t reallen = (len + SEG_ALIGN_1) & ~SEG_ALIGN_1;
1548 int32_t align = reallen - len;
1549 if (elf_sects[i].is_saa)
1550 saa_fpwrite(elf_sects[i].data, elffp);
1551 else
1552 fwrite(elf_sects[i].data, len, 1, elffp);
1553 fwrite(align_str, align, 1, elffp);
1554 }
1555 }
1556
1557 static void elf_sect_write(struct Section *sect, const void *data, size_t len)
1558 {
1559 saa_wbytes(sect->data, data, len);
1560 sect->len += len;
1561 }
1562 static void elf_sect_writeaddr(struct Section *sect, int64_t data, size_t len)
1563 {
1564 saa_writeaddr(sect->data, data, len);
1565 sect->len += len;
1566 }
1567
1568 static int32_t elf_segbase(int32_t segment)
1569 {
1570 return segment;
1571 }
1572
1573 static int elf_directive(char *directive, char *value, int pass)
1574 {
1575 bool err;
1576 int64_t n;
1577 char *p;
1578
1579 if (!strcmp(directive, "osabi")) {
1580 if (pass == 2)
1581 return 1; /* ignore in pass 2 */
1582
1583 n = readnum(value, &err);
1584 if (err) {
1585 error(ERR_NONFATAL, "`osabi' directive requires a parameter");
1586 return 1;
1587 }
1588 if (n < 0 || n > 255) {
1589 error(ERR_NONFATAL, "valid osabi numbers are 0 to 255");
1590 return 1;
1591 }
1592 elf_osabi = n;
1593 elf_abiver = 0;
1594
1595 if ((p = strchr(value,',')) == NULL)
1596 return 1;
1597
1598 n = readnum(p+1, &err);
1599 if (err || n < 0 || n > 255) {
1600 error(ERR_NONFATAL, "invalid ABI version number (valid: 0 to 255)");
1601 return 1;
1602 }
1603
1604 elf_abiver = n;
1605 return 1;
1606 }
1607
1608 return 0;
1609 }
1610
1611 static void elf_filename(char *inname, char *outname, efunc error)
1612 {
1613 strcpy(elf_module, inname);
1614 standard_extension(inname, outname, ".o", error);
1615 }
1616
1617 extern macros_t elf_stdmac[];
1618
1619 static int elf_set_info(enum geninfo type, char **val)
1620 {
1621 (void)type;
1622 (void)val;
1623 return 0;
1624 }
1625 static struct dfmt df_dwarf = {
1626 "ELF64 (X86_64) dwarf debug format for Linux",
1627 "dwarf",
1628 debug64_init,
1629 dwarf64_linenum,
1630 debug64_deflabel,
1631 debug64_directive,
1632 debug64_typevalue,
1633 dwarf64_output,
1634 dwarf64_cleanup
1635 };
1636 static struct dfmt df_stabs = {
1637 "ELF64 (X86_64) stabs debug format for Linux",
1638 "stabs",
1639 debug64_init,
1640 stabs64_linenum,
1641 debug64_deflabel,
1642 debug64_directive,
1643 debug64_typevalue,
1644 stabs64_output,
1645 stabs64_cleanup
1646 };
1647
1648 struct dfmt *elf64_debugs_arr[3] = { &df_stabs, &df_dwarf, NULL };
1649
1650 struct ofmt of_elf64 = {
1651 "ELF64 (x86_64) object files (e.g. Linux)",
1652 "elf64",
1653 NULL,
1654 elf64_debugs_arr,
1655 &null_debug_form,
1656 elf_stdmac,
1657 elf_init,
1658 elf_set_info,
1659 elf_out,
1660 elf_deflabel,
1661 elf_section_names,
1662 elf_segbase,
1663 elf_directive,
1664 elf_filename,
1665 elf_cleanup
1666 };
1667
1668 /* common debugging routines */
1669 void debug64_init(struct ofmt *of, void *id, FILE * fp, efunc error)
1670 {
1671 (void)of;
1672 (void)id;
1673 (void)fp;
1674 (void)error;
1675 }
1676 void debug64_deflabel(char *name, int32_t segment, int64_t offset, int is_global,
1677 char *special)
1678 {
1679 (void)name;
1680 (void)segment;
1681 (void)offset;
1682 (void)is_global;
1683 (void)special;
1684 }
1685
1686 void debug64_directive(const char *directive, const char *params)
1687 {
1688 (void)directive;
1689 (void)params;
1690 }
1691
1692 void debug64_typevalue(int32_t type)
1693 {
1694 int32_t stype, ssize;
1695 switch (TYM_TYPE(type)) {
1696 case TY_LABEL:
1697 ssize = 0;
1698 stype = STT_NOTYPE;
1699 break;
1700 case TY_BYTE:
1701 ssize = 1;
1702 stype = STT_OBJECT;
1703 break;
1704 case TY_WORD:
1705 ssize = 2;
1706 stype = STT_OBJECT;
1707 break;
1708 case TY_DWORD:
1709 ssize = 4;
1710 stype = STT_OBJECT;
1711 break;
1712 case TY_FLOAT:
1713 ssize = 4;
1714 stype = STT_OBJECT;
1715 break;
1716 case TY_QWORD:
1717 ssize = 8;
1718 stype = STT_OBJECT;
1719 break;
1720 case TY_TBYTE:
1721 ssize = 10;
1722 stype = STT_OBJECT;
1723 break;
1724 case TY_OWORD:
1725 ssize = 16;
1726 stype = STT_OBJECT;
1727 break;
1728 case TY_COMMON:
1729 ssize = 0;
1730 stype = STT_COMMON;
1731 break;
1732 case TY_SEG:
1733 ssize = 0;
1734 stype = STT_SECTION;
1735 break;
1736 case TY_EXTERN:
1737 ssize = 0;
1738 stype = STT_NOTYPE;
1739 break;
1740 case TY_EQU:
1741 ssize = 0;
1742 stype = STT_NOTYPE;
1743 break;
1744 default:
1745 ssize = 0;
1746 stype = STT_NOTYPE;
1747 break;
1748 }
1749 if (stype == STT_OBJECT && lastsym && !lastsym->type) {
1750 lastsym->size = ssize;
1751 lastsym->type = stype;
1752 }
1753 }
1754
1755 /* stabs debugging routines */
1756
1757
1758 void stabs64_linenum(const char *filename, int32_t linenumber, int32_t segto)
1759 {
1760 (void)segto;
1761 if (!stabs_filename) {
1762 stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
1763 strcpy(stabs_filename, filename);
1764 } else {
1765 if (strcmp(stabs_filename, filename)) {
1766 /* yep, a memory leak...this program is one-shot anyway, so who cares...
1767 in fact, this leak comes in quite handy to maintain a list of files
1768 encountered so far in the symbol lines... */
1769
1770 /* why not nasm_free(stabs_filename); we're done with the old one */
1771
1772 stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
1773 strcpy(stabs_filename, filename);
1774 }
1775 }
1776 debug_immcall = 1;
1777 currentline = linenumber;
1778 }
1779
1780
1781 void stabs64_output(int type, void *param)
1782 {
1783 struct symlininfo *s;
1784 struct linelist *el;
1785 if (type == TY_DEBUGSYMLIN) {
1786 if (debug_immcall) {
1787 s = (struct symlininfo *)param;
1788 if (!(sects[s->section]->flags & SHF_EXECINSTR))
1789 return; /* line info is only collected for executable sections */
1790 numlinestabs++;
1791 el = (struct linelist *)nasm_malloc(sizeof(struct linelist));
1792 el->info.offset = s->offset;
1793 el->info.section = s->section;
1794 el->info.name = s->name;
1795 el->line = currentline;
1796 el->filename = stabs_filename;
1797 el->next = 0;
1798 if (stabslines) {
1799 stabslines->last->next = el;
1800 stabslines->last = el;
1801 } else {
1802 stabslines = el;
1803 stabslines->last = el;
1804 }
1805 }
1806 }
1807 debug_immcall = 0;
1808 }
1809
1810 #define WRITE_STAB(p,n_strx,n_type,n_other,n_desc,n_value) \
1811 do {\
1812 WRITELONG(p,n_strx); \
1813 WRITECHAR(p,n_type); \
1814 WRITECHAR(p,n_other); \
1815 WRITESHORT(p,n_desc); \
1816 WRITELONG(p,n_value); \
1817 } while (0)
1818
1819 /* for creating the .stab , .stabstr and .rel.stab sections in memory */
1820
1821 void stabs64_generate(void)
1822 {
1823 int i, numfiles, strsize, numstabs = 0, currfile, mainfileindex;
1824 uint8_t *sbuf, *ssbuf, *rbuf, *sptr, *rptr;
1825 char **allfiles;
1826 int *fileidx;
1827
1828 struct linelist *ptr;
1829
1830 ptr = stabslines;
1831
1832 allfiles = (char **)nasm_malloc(numlinestabs * sizeof(int8_t *));
1833 for (i = 0; i < numlinestabs; i++)
1834 allfiles[i] = 0;
1835 numfiles = 0;
1836 while (ptr) {
1837 if (numfiles == 0) {
1838 allfiles[0] = ptr->filename;
1839 numfiles++;
1840 } else {
1841 for (i = 0; i < numfiles; i++) {
1842 if (!strcmp(allfiles[i], ptr->filename))
1843 break;
1844 }
1845 if (i >= numfiles) {
1846 allfiles[i] = ptr->filename;
1847 numfiles++;
1848 }
1849 }
1850 ptr = ptr->next;
1851 }
1852 strsize = 1;
1853 fileidx = (int *)nasm_malloc(numfiles * sizeof(int));
1854 for (i = 0; i < numfiles; i++) {
1855 fileidx[i] = strsize;
1856 strsize += strlen(allfiles[i]) + 1;
1857 }
1858 mainfileindex = 0;
1859 for (i = 0; i < numfiles; i++) {
1860 if (!strcmp(allfiles[i], elf_module)) {
1861 mainfileindex = i;
1862 break;
1863 }
1864 }
1865
1866 /* worst case size of the stab buffer would be:
1867 the sourcefiles changes each line, which would mean 1 SOL, 1 SYMLIN per line
1868 */
1869 sbuf =
1870 (uint8_t *)nasm_malloc((numlinestabs * 2 + 3) *
1871 sizeof(struct stabentry));
1872
1873 ssbuf = (uint8_t *)nasm_malloc(strsize);
1874
1875 rbuf = (uint8_t *)nasm_malloc(numlinestabs * 16 * (2 + 3));
1876 rptr = rbuf;
1877
1878 for (i = 0; i < numfiles; i++) {
1879 strcpy((char *)ssbuf + fileidx[i], allfiles[i]);
1880 }
1881 ssbuf[0] = 0;
1882
1883 stabstrlen = strsize; /* set global variable for length of stab strings */
1884
1885 sptr = sbuf;
1886 ptr = stabslines;
1887 numstabs = 0;
1888
1889 if (ptr) {
1890 /* this is the first stab, its strx points to the filename of the
1891 the source-file, the n_desc field should be set to the number
1892 of remaining stabs
1893 */
1894 WRITE_STAB(sptr, fileidx[0], 0, 0, 0, strlen(allfiles[0] + 12));
1895
1896 /* this is the stab for the main source file */
1897 WRITE_STAB(sptr, fileidx[mainfileindex], N_SO, 0, 0, 0);
1898
1899 /* relocation table entry */
1900
1901 /* Since the symbol table has two entries before */
1902 /* the section symbols, the index in the info.section */
1903 /* member must be adjusted by adding 2 */
1904
1905 WRITEDLONG(rptr, (int64_t)(sptr - sbuf) - 4);
1906 WRITELONG(rptr, R_X86_64_32);
1907 WRITELONG(rptr, ptr->info.section + 2);
1908
1909 numstabs++;
1910 currfile = mainfileindex;
1911 }
1912
1913 while (ptr) {
1914 if (strcmp(allfiles[currfile], ptr->filename)) {
1915 /* oops file has changed... */
1916 for (i = 0; i < numfiles; i++)
1917 if (!strcmp(allfiles[i], ptr->filename))
1918 break;
1919 currfile = i;
1920 WRITE_STAB(sptr, fileidx[currfile], N_SOL, 0, 0,
1921 ptr->info.offset);
1922 numstabs++;
1923
1924 /* relocation table entry */
1925
1926 WRITEDLONG(rptr, (int64_t)(sptr - sbuf) - 4);
1927 WRITELONG(rptr, R_X86_64_32);
1928 WRITELONG(rptr, ptr->info.section + 2);
1929 }
1930
1931 WRITE_STAB(sptr, 0, N_SLINE, 0, ptr->line, ptr->info.offset);
1932 numstabs++;
1933
1934 /* relocation table entry */
1935
1936 WRITEDLONG(rptr, (int64_t)(sptr - sbuf) - 4);
1937 WRITELONG(rptr, R_X86_64_32);
1938 WRITELONG(rptr, ptr->info.section + 2);
1939
1940 ptr = ptr->next;
1941
1942 }
1943
1944 ((struct stabentry *)sbuf)->n_desc = numstabs;
1945
1946 nasm_free(allfiles);
1947 nasm_free(fileidx);
1948
1949 stablen = (sptr - sbuf);
1950 stabrellen = (rptr - rbuf);
1951 stabrelbuf = rbuf;
1952 stabbuf = sbuf;
1953 stabstrbuf = ssbuf;
1954 }
1955
1956 void stabs64_cleanup(void)
1957 {
1958 struct linelist *ptr, *del;
1959 if (!stabslines)
1960 return;
1961 ptr = stabslines;
1962 while (ptr) {
1963 del = ptr;
1964 ptr = ptr->next;
1965 nasm_free(del);
1966 }
1967 if (stabbuf)
1968 nasm_free(stabbuf);
1969 if (stabrelbuf)
1970 nasm_free(stabrelbuf);
1971 if (stabstrbuf)
1972 nasm_free(stabstrbuf);
1973 }
1974 /* dwarf routines */
1975
1976
1977 void dwarf64_linenum(const char *filename, int32_t linenumber, int32_t segto)
1978 {
1979 (void)segto;
1980 dwarf64_findfile(filename);
1981 debug_immcall = 1;
1982 currentline = linenumber;
1983 }
1984
1985 /* called from elf_out with type == TY_DEBUGSYMLIN */
1986 void dwarf64_output(int type, void *param)
1987 {
1988 int ln, aa, inx, maxln, soc;
1989 struct symlininfo *s;
1990 struct SAA *plinep;
1991
1992 (void)type;
1993
1994 s = (struct symlininfo *)param;
1995 /* line number info is only gathered for executable sections */
1996 if (!(sects[s->section]->flags & SHF_EXECINSTR))
1997 return;
1998 /* Check if section index has changed */
1999 if (!(dwarf_csect && (dwarf_csect->section) == (s->section)))
2000 {
2001 dwarf64_findsect(s->section);
2002 }
2003 /* do nothing unless line or file has changed */
2004 if (debug_immcall)
2005 {
2006 ln = currentline - dwarf_csect->line;
2007 aa = s->offset - dwarf_csect->offset;
2008 inx = dwarf_clist->line;
2009 plinep = dwarf_csect->psaa;
2010 /* check for file change */
2011 if (!(inx == dwarf_csect->file))
2012 {
2013 saa_write8(plinep,DW_LNS_set_file);
2014 saa_write8(plinep,inx);
2015 dwarf_csect->file = inx;
2016 }
2017 /* check for line change */
2018 if (ln)
2019 {
2020 /* test if in range of special op code */
2021 maxln = line_base + line_range;
2022 soc = (ln - line_base) + (line_range * aa) + opcode_base;
2023 if (ln >= line_base && ln < maxln && soc < 256)
2024 {
2025 saa_write8(plinep,soc);
2026 }
2027 else
2028 {
2029 if (ln)
2030 {
2031 saa_write8(plinep,DW_LNS_advance_line);
2032 saa_wleb128s(plinep,ln);
2033 }
2034 if (aa)
2035 {
2036 saa_write8(plinep,DW_LNS_advance_pc);
2037 saa_wleb128u(plinep,aa);
2038 }
2039 }
2040 dwarf_csect->line = currentline;
2041 dwarf_csect->offset = s->offset;
2042 }
2043 /* show change handled */
2044 debug_immcall = 0;
2045 }
2046 }
2047
2048
2049 void dwarf64_generate(void)
2050 {
2051 static const char nasm_signature[] = "NASM " NASM_VER;
2052 uint8_t *pbuf;
2053 int indx;
2054 struct linelist *ftentry;
2055 struct SAA *paranges, *ppubnames, *pinfo, *pabbrev, *plines, *plinep;
2056 struct SAA *parangesrel, *plinesrel, *pinforel;
2057 struct sectlist *psect;
2058 size_t saalen, linepoff, totlen, highaddr;
2059
2060 /* write epilogues for each line program range */
2061 /* and build aranges section */
2062 paranges = saa_init(1L);
2063 parangesrel = saa_init(1L);
2064 saa_write16(paranges,3); /* dwarf version */
2065 saa_write64(parangesrel, paranges->datalen+4);
2066 saa_write64(parangesrel, (dwarf_infosym << 32) + R_X86_64_32); /* reloc to info */
2067 saa_write64(parangesrel, 0);
2068 saa_write32(paranges,0); /* offset into info */
2069 saa_write8(paranges,8); /* pointer size */
2070 saa_write8(paranges,0); /* not segmented */
2071 saa_write32(paranges,0); /* padding */
2072 /* iterate though sectlist entries */
2073 psect = dwarf_fsect;
2074 totlen = 0;
2075 highaddr = 0;
2076 for (indx = 0; indx < dwarf_nsections; indx++)
2077 {
2078 plinep = psect->psaa;
2079 /* Line Number Program Epilogue */
2080 saa_write8(plinep,2); /* std op 2 */
2081 saa_write8(plinep,(sects[psect->section]->len)-psect->offset);
2082 saa_write8(plinep,DW_LNS_extended_op);
2083 saa_write8(plinep,1); /* operand length */
2084 saa_write8(plinep,DW_LNE_end_sequence);
2085 totlen += plinep->datalen;
2086 /* range table relocation entry */
2087 saa_write64(parangesrel, paranges->datalen + 4);
2088 saa_write64(parangesrel, ((uint64_t) (psect->section + 2) << 32) + R_X86_64_64);
2089 saa_write64(parangesrel, (uint64_t) 0);
2090 /* range table entry */
2091 saa_write64(paranges,0x0000); /* range start */
2092 saa_write64(paranges,sects[psect->section]->len); /* range length */
2093 highaddr += sects[psect->section]->len;
2094 /* done with this entry */
2095 psect = psect->next;
2096 }
2097 saa_write64(paranges,0); /* null address */
2098 saa_write64(paranges,0); /* null length */
2099 saalen = paranges->datalen;
2100 arangeslen = saalen + 4;
2101 arangesbuf = pbuf = nasm_malloc(arangeslen);
2102 WRITELONG(pbuf,saalen); /* initial length */
2103 saa_rnbytes(paranges, pbuf, saalen);
2104 saa_free(paranges);
2105
2106 /* build rela.aranges section */
2107 arangesrellen = saalen = parangesrel->datalen;
2108 arangesrelbuf = pbuf = nasm_malloc(arangesrellen);
2109 saa_rnbytes(parangesrel, pbuf, saalen);
2110 saa_free(parangesrel);
2111
2112 /* build pubnames section */
2113 ppubnames = saa_init(1L);
2114 saa_write16(ppubnames,3); /* dwarf version */
2115 saa_write32(ppubnames,0); /* offset into info */
2116 saa_write32(ppubnames,0); /* space used in info */
2117 saa_write32(ppubnames,0); /* end of list */
2118 saalen = ppubnames->datalen;
2119 pubnameslen = saalen + 4;
2120 pubnamesbuf = pbuf = nasm_malloc(pubnameslen);
2121 WRITELONG(pbuf,saalen); /* initial length */
2122 saa_rnbytes(ppubnames, pbuf, saalen);
2123 saa_free(ppubnames);
2124
2125 /* build info section */
2126 pinfo = saa_init(1L);
2127 pinforel = saa_init(1L);
2128 saa_write16(pinfo,3); /* dwarf version */
2129 saa_write64(pinforel, pinfo->datalen + 4);
2130 saa_write64(pinforel, (dwarf_abbrevsym << 32) + R_X86_64_32); /* reloc to abbrev */
2131 saa_write64(pinforel, 0);
2132 saa_write32(pinfo,0); /* offset into abbrev */
2133 saa_write8(pinfo,8); /* pointer size */
2134 saa_write8(pinfo,1); /* abbrviation number LEB128u */
2135 saa_write64(pinforel, pinfo->datalen + 4);
2136 saa_write64(pinforel, ((uint64_t)(dwarf_fsect->section + 2) << 32) + R_X86_64_64);
2137 saa_write64(pinforel, 0);
2138 saa_write64(pinfo,0); /* DW_AT_low_pc */
2139 saa_write64(pinforel, pinfo->datalen + 4);
2140 saa_write64(pinforel, ((uint64_t)(dwarf_fsect->section + 2) << 32) + R_X86_64_64);
2141 saa_write64(pinforel, 0);
2142 saa_write64(pinfo,highaddr); /* DW_AT_high_pc */
2143 saa_write64(pinforel, pinfo->datalen + 4);
2144 saa_write64(pinforel, (dwarf_linesym << 32) + R_X86_64_32); /* reloc to line */
2145 saa_write64(pinforel, 0);
2146 saa_write32(pinfo,0); /* DW_AT_stmt_list */
2147 saa_wbytes(pinfo, elf_module, strlen(elf_module)+1);
2148 saa_wbytes(pinfo, nasm_signature, strlen(nasm_signature)+1);
2149 saa_write16(pinfo,DW_LANG_Mips_Assembler);
2150 saa_write8(pinfo,2); /* abbrviation number LEB128u */
2151 saa_write64(pinforel, pinfo->datalen + 4);
2152 saa_write64(pinforel, ((uint64_t)(dwarf_fsect->section + 2) << 32) + R_X86_64_64);
2153 saa_write64(pinforel, 0);
2154 saa_write64(pinfo,0); /* DW_AT_low_pc */
2155 saa_write64(pinfo,0); /* DW_AT_frame_base */
2156 saa_write8(pinfo,0); /* end of entries */
2157 saalen = pinfo->datalen;
2158 infolen = saalen + 4;
2159 infobuf = pbuf = nasm_malloc(infolen);
2160 WRITELONG(pbuf,saalen); /* initial length */
2161 saa_rnbytes(pinfo, pbuf, saalen);
2162 saa_free(pinfo);
2163
2164 /* build rela.info section */
2165 inforellen = saalen = pinforel->datalen;
2166 inforelbuf = pbuf = nasm_malloc(inforellen);
2167 saa_rnbytes(pinforel, pbuf, saalen);
2168 saa_free(pinforel);
2169
2170 /* build abbrev section */
2171 pabbrev = saa_init(1L);
2172 saa_write8(pabbrev,1); /* entry number LEB128u */
2173 saa_write8(pabbrev,DW_TAG_compile_unit); /* tag LEB128u */
2174 saa_write8(pabbrev,1); /* has children */
2175 /* the following attributes and forms are all LEB128u values */
2176 saa_write8(pabbrev,DW_AT_low_pc);
2177 saa_write8(pabbrev,DW_FORM_addr);
2178 saa_write8(pabbrev,DW_AT_high_pc);
2179 saa_write8(pabbrev,DW_FORM_addr);
2180 saa_write8(pabbrev,DW_AT_stmt_list);
2181 saa_write8(pabbrev,DW_FORM_data4);
2182 saa_write8(pabbrev,DW_AT_name);
2183 saa_write8(pabbrev,DW_FORM_string);
2184 saa_write8(pabbrev,DW_AT_producer);
2185 saa_write8(pabbrev,DW_FORM_string);
2186 saa_write8(pabbrev,DW_AT_language);
2187 saa_write8(pabbrev,DW_FORM_data2);
2188 saa_write16(pabbrev,0); /* end of entry */
2189 /* LEB128u usage same as above */
2190 saa_write8(pabbrev,2); /* entry number */
2191 saa_write8(pabbrev,DW_TAG_subprogram);
2192 saa_write8(pabbrev,0); /* no children */
2193 saa_write8(pabbrev,DW_AT_low_pc);
2194 saa_write8(pabbrev,DW_FORM_addr);
2195 saa_write8(pabbrev,DW_AT_frame_base);
2196 saa_write8(pabbrev,DW_FORM_data4);
2197 saa_write16(pabbrev,0); /* end of entry */
2198 abbrevlen = saalen = pabbrev->datalen;
2199 abbrevbuf = pbuf = nasm_malloc(saalen);
2200 saa_rnbytes(pabbrev, pbuf, saalen);
2201 saa_free(pabbrev);
2202
2203 /* build line section */
2204 /* prolog */
2205 plines = saa_init(1L);
2206 saa_write8(plines,1); /* Minimum Instruction Length */
2207 saa_write8(plines,1); /* Initial value of 'is_stmt' */
2208 saa_write8(plines,line_base); /* Line Base */
2209 saa_write8(plines,line_range); /* Line Range */
2210 saa_write8(plines,opcode_base); /* Opcode Base */
2211 /* standard opcode lengths (# of LEB128u operands) */
2212 saa_write8(plines,0); /* Std opcode 1 length */
2213 saa_write8(plines,1); /* Std opcode 2 length */
2214 saa_write8(plines,1); /* Std opcode 3 length */
2215 saa_write8(plines,1); /* Std opcode 4 length */
2216 saa_write8(plines,1); /* Std opcode 5 length */
2217 saa_write8(plines,0); /* Std opcode 6 length */
2218 saa_write8(plines,0); /* Std opcode 7 length */
2219 saa_write8(plines,0); /* Std opcode 8 length */
2220 saa_write8(plines,1); /* Std opcode 9 length */
2221 saa_write8(plines,0); /* Std opcode 10 length */
2222 saa_write8(plines,0); /* Std opcode 11 length */
2223 saa_write8(plines,1); /* Std opcode 12 length */
2224 /* Directory Table */
2225 saa_write8(plines,0); /* End of table */
2226 /* File Name Table */
2227 ftentry = dwarf_flist;
2228 for (indx = 0;indx<dwarf_numfiles;indx++)
2229 {
2230 saa_wbytes(plines, ftentry->filename, (int32_t)(strlen(ftentry->filename) + 1));
2231 saa_write8(plines,0); /* directory LEB128u */
2232 saa_write8(plines,0); /* time LEB128u */
2233 saa_write8(plines,0); /* size LEB128u */
2234 ftentry = ftentry->next;
2235 }
2236 saa_write8(plines,0); /* End of table */
2237 linepoff = plines->datalen;
2238 linelen = linepoff + totlen + 10;
2239 linebuf = pbuf = nasm_malloc(linelen);
2240 WRITELONG(pbuf,linelen-4); /* initial length */
2241 WRITESHORT(pbuf,3); /* dwarf version */
2242 WRITELONG(pbuf,linepoff); /* offset to line number program */
2243 /* write line header */
2244 saalen = linepoff;
2245 saa_rnbytes(plines, pbuf, saalen); /* read a given no. of bytes */
2246 pbuf += linepoff;
2247 saa_free(plines);
2248 /* concatonate line program ranges */
2249 linepoff += 13;
2250 plinesrel = saa_init(1L);
2251 psect = dwarf_fsect;
2252 for (indx = 0; indx < dwarf_nsections; indx++)
2253 {
2254 saa_write64(plinesrel, linepoff);
2255 saa_write64(plinesrel, ((uint64_t) (psect->section + 2) << 32) + R_X86_64_64);
2256 saa_write64(plinesrel, (uint64_t) 0);
2257 plinep = psect->psaa;
2258 saalen = plinep->datalen;
2259 saa_rnbytes(plinep, pbuf, saalen);
2260 pbuf += saalen;
2261 linepoff += saalen;
2262 saa_free(plinep);
2263 /* done with this entry */
2264 psect = psect->next;
2265 }
2266
2267
2268 /* build rela.lines section */
2269 linerellen =saalen = plinesrel->datalen;
2270 linerelbuf = pbuf = nasm_malloc(linerellen);
2271 saa_rnbytes(plinesrel, pbuf, saalen);
2272 saa_free(plinesrel);
2273
2274 /* build frame section */
2275 framelen = 4;
2276 framebuf = pbuf = nasm_malloc(framelen);
2277 WRITELONG(pbuf,framelen-4); /* initial length */
2278
2279 /* build loc section */
2280 loclen = 16;
2281 locbuf = pbuf = nasm_malloc(loclen);
2282 WRITEDLONG(pbuf,0); /* null beginning offset */
2283 WRITEDLONG(pbuf,0); /* null ending offset */
2284 }
2285
2286 void dwarf64_cleanup(void)
2287 {
2288 if (arangesbuf)
2289 nasm_free(arangesbuf);
2290 if (arangesrelbuf)
2291 nasm_free(arangesrelbuf);
2292 if (pubnamesbuf)
2293 nasm_free(pubnamesbuf);
2294 if (infobuf)
2295 nasm_free(infobuf);
2296 if (inforelbuf)
2297 nasm_free(inforelbuf);
2298 if (abbrevbuf)
2299 nasm_free(abbrevbuf);
2300 if (linebuf)
2301 nasm_free(linebuf);
2302 if (linerelbuf)
2303 nasm_free(linerelbuf);
2304 if (framebuf)
2305 nasm_free(framebuf);
2306 if (locbuf)
2307 nasm_free(locbuf);
2308 }
2309 void dwarf64_findfile(const char * fname)
2310 {
2311 int finx;
2312 struct linelist *match;
2313
2314 /* return if fname is current file name */
2315 if (dwarf_clist && !(strcmp(fname, dwarf_clist->filename))) return;
2316 /* search for match */
2317 else
2318 {
2319 match = 0;
2320 if (dwarf_flist)
2321 {
2322 match = dwarf_flist;
2323 for (finx = 0; finx < dwarf_numfiles; finx++)
2324 {
2325 if (!(strcmp(fname, match->filename)))
2326 {
2327 dwarf_clist = match;
2328 return;
2329 }
2330 }
2331 }
2332 /* add file name to end of list */
2333 dwarf_clist = (struct linelist *)nasm_malloc(sizeof(struct linelist));
2334 dwarf_numfiles++;
2335 dwarf_clist->line = dwarf_numfiles;
2336 dwarf_clist->filename = nasm_malloc(strlen(fname) + 1);
2337 strcpy(dwarf_clist->filename,fname);
2338 dwarf_clist->next = 0;
2339 /* if first entry */
2340 if (!dwarf_flist)
2341 {
2342 dwarf_flist = dwarf_elist = dwarf_clist;
2343 dwarf_clist->last = 0;
2344 }
2345 /* chain to previous entry */
2346 else
2347 {
2348 dwarf_elist->next = dwarf_clist;
2349 dwarf_elist = dwarf_clist;
2350 }
2351 }
2352 }
2353 /* */
2354 void dwarf64_findsect(const int index)
2355 {
2356 int sinx;
2357 struct sectlist *match;
2358 struct SAA *plinep;
2359 /* return if index is current section index */
2360 if (dwarf_csect && (dwarf_csect->section == index))
2361 {
2362 return;
2363 }
2364 /* search for match */
2365 else
2366 {
2367 match = 0;
2368 if (dwarf_fsect)
2369 {
2370 match = dwarf_fsect;
2371 for (sinx = 0; sinx < dwarf_nsections; sinx++)
2372 {
2373 if ((match->section == index))
2374 {
2375 dwarf_csect = match;
2376 return;
2377 }
2378 match = match->next;
2379 }
2380 }
2381 /* add entry to end of list */
2382 dwarf_csect = (struct sectlist *)nasm_malloc(sizeof(struct sectlist));
2383 dwarf_nsections++;
2384 dwarf_csect->psaa = plinep = saa_init(1L);
2385 dwarf_csect->line = 1;
2386 dwarf_csect->offset = 0;
2387 dwarf_csect->file = 1;
2388 dwarf_csect->section = index;
2389 dwarf_csect->next = 0;
2390 /* set relocatable address at start of line program */
2391 saa_write8(plinep,DW_LNS_extended_op);
2392 saa_write8(plinep,9); /* operand length */
2393 saa_write8(plinep,DW_LNE_set_address);
2394 saa_write64(plinep,0); /* Start Address */
2395 /* if first entry */
2396 if (!dwarf_fsect)
2397 {
2398 dwarf_fsect = dwarf_esect = dwarf_csect;
2399 dwarf_csect->last = 0;
2400 }
2401 /* chain to previous entry */
2402 else
2403 {
2404 dwarf_esect->next = dwarf_csect;
2405 dwarf_esect = dwarf_csect;
2406 }
2407 }
2408 }
2409
2410 #endif /* OF_ELF */
The Netwide Assembler