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nasm/output/outelfx32.c

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backend: add support for x32 ELF Add an x32 ELF (32-bit code with the CPU in 64-bit mode) backend.
2012-02-04 04:06:04 +08:00
/* ----------------------------------------------------------------------- *
*
* Copyright 2012 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following
* conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ----------------------------------------------------------------------- */
/*
* outelfx32.c output routines for the Netwide Assembler to produce
* ELF32 (x86_64) object file format
*/
#include "compiler.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include "nasm.h"
#include "nasmlib.h"
#include "saa.h"
#include "raa.h"
#include "stdscan.h"
#include "eval.h"
#include "output/outform.h"
#include "output/outlib.h"
#include "rbtree.h"
#include "output/dwarf.h"
#include "output/stabs.h"
#include "output/outelf.h"
#ifdef OF_ELFX32
/*
* Relocation types.
*/
struct Reloc {
struct Reloc *next;
int32_t address; /* relative to _start_ of section */
int32_t symbol; /* symbol index */
int32_t offset; /* symbol addend */
int type; /* type of relocation */
};
struct Symbol {
struct rbtree symv; /* symbol value and rbtree of globals */
int32_t strpos; /* string table position of name */
int32_t section; /* section ID of the symbol */
int type; /* symbol type */
int other; /* symbol visibility */
int32_t size; /* size of symbol */
int32_t globnum; /* symbol table offset if global */
struct Symbol *nextfwd; /* list of unresolved-size symbols */
char *name; /* used temporarily if in above list */
};
struct Section {
struct SAA *data;
uint32_t len, size, nrelocs;
int32_t index; /* index into sects array */
int type; /* SHT_PROGBITS or SHT_NOBITS */
uint32_t align; /* alignment: power of two */
uint32_t flags; /* section flags */
char *name;
struct SAA *rel;
uint32_t rellen;
struct Reloc *head, **tail;
struct rbtree *gsyms; /* global symbols in section */
};
#define SECT_DELTA 32
static struct Section **sects;
static int nsects, sectlen;
#define SHSTR_DELTA 256
static char *shstrtab;
static int shstrtablen, shstrtabsize;
static struct SAA *syms;
static uint32_t nlocals, nglobs, ndebugs; /* Symbol counts */
static int32_t def_seg;
static struct RAA *bsym;
static struct SAA *strs;
static uint32_t strslen;
static struct Symbol *fwds;
static char elf_module[FILENAME_MAX];
static uint8_t elf_osabi = 0; /* Default OSABI = 0 (System V or Linux) */
static uint8_t elf_abiver = 0; /* Current ABI version */
extern struct ofmt of_elfx32;
static struct ELF_SECTDATA {
void *data;
int32_t len;
bool is_saa;
} *elf_sects;
static int elf_nsect, nsections;
static int32_t elf_foffs;
static void elf_write(void);
static void elf_sect_write(struct Section *, const void *, size_t);
static void elf_sect_writeaddr(struct Section *, int32_t, size_t);
static void elf_section_header(int, int, uint32_t, void *, bool, uint32_t, int, int,
int, int);
static void elf_write_sections(void);
static struct SAA *elf_build_symtab(int32_t *, int32_t *);
static struct SAA *elf_build_reltab(uint32_t *, struct Reloc *);
static void add_sectname(char *, char *);
struct erel {
int offset, info;
};
struct symlininfo {
int offset;
int section; /* index into sects[] */
int segto; /* internal section number */
char *name; /* shallow-copied pointer of section name */
};
struct linelist {
struct linelist *next;
struct linelist *last;
struct symlininfo info;
char *filename;
int line;
};
struct sectlist {
struct SAA *psaa;
int section;
int line;
int offset;
int file;
struct sectlist *next;
struct sectlist *last;
};
/* common debug variables */
static int currentline = 1;
static int debug_immcall = 0;
/* stabs debug variables */
static struct linelist *stabslines = 0;
static int numlinestabs = 0;
static char *stabs_filename = 0;
static uint8_t *stabbuf = 0, *stabstrbuf = 0, *stabrelbuf = 0;
static int stablen, stabstrlen, stabrellen;
/* dwarf debug variables */
static struct linelist *dwarf_flist = 0, *dwarf_clist = 0, *dwarf_elist = 0;
static struct sectlist *dwarf_fsect = 0, *dwarf_csect = 0, *dwarf_esect = 0;
static int dwarf_numfiles = 0, dwarf_nsections;
static uint8_t *arangesbuf = 0, *arangesrelbuf = 0, *pubnamesbuf = 0, *infobuf = 0, *inforelbuf = 0,
*abbrevbuf = 0, *linebuf = 0, *linerelbuf = 0, *framebuf = 0, *locbuf = 0;
static int8_t line_base = -5, line_range = 14, opcode_base = 13;
static int arangeslen, arangesrellen, pubnameslen, infolen, inforellen,
abbrevlen, linelen, linerellen, framelen, loclen;
static int32_t dwarf_infosym, dwarf_abbrevsym, dwarf_linesym;
static struct dfmt df_dwarf;
static struct dfmt df_stabs;
static struct Symbol *lastsym;
/* common debugging routines */
static void debugx32_typevalue(int32_t);
static void debugx32_deflabel(char *, int32_t, int64_t, int, char *);
static void debugx32_directive(const char *, const char *);
/* stabs debugging routines */
static void stabsx32_linenum(const char *filename, int32_t linenumber, int32_t);
static void stabsx32_output(int, void *);
static void stabsx32_generate(void);
static void stabsx32_cleanup(void);
/* dwarf debugging routines */
static void dwarfx32_init(void);
static void dwarfx32_linenum(const char *filename, int32_t linenumber, int32_t);
static void dwarfx32_output(int, void *);
static void dwarfx32_generate(void);
static void dwarfx32_cleanup(void);
static void dwarfx32_findfile(const char *);
static void dwarfx32_findsect(const int);
/*
* Special section numbers which are used to define ELF special
* symbols, which can be used with WRT to provide PIC relocation
* types.
*/
static int32_t elf_gotpc_sect, elf_gotoff_sect;
static int32_t elf_got_sect, elf_plt_sect;
static int32_t elf_sym_sect;
static int32_t elf_gottpoff_sect;
static void elf_init(void)
{
maxbits = 64;
sects = NULL;
nsects = sectlen = 0;
syms = saa_init((int32_t)sizeof(struct Symbol));
nlocals = nglobs = ndebugs = 0;
bsym = raa_init();
strs = saa_init(1L);
saa_wbytes(strs, "\0", 1L);
saa_wbytes(strs, elf_module, strlen(elf_module)+1);
strslen = 2 + strlen(elf_module);
shstrtab = NULL;
shstrtablen = shstrtabsize = 0;;
add_sectname("", "");
fwds = NULL;
elf_gotpc_sect = seg_alloc();
define_label("..gotpc", elf_gotpc_sect + 1, 0L, NULL, false, false);
elf_gotoff_sect = seg_alloc();
define_label("..gotoff", elf_gotoff_sect + 1, 0L, NULL, false, false);
elf_got_sect = seg_alloc();
define_label("..got", elf_got_sect + 1, 0L, NULL, false, false);
elf_plt_sect = seg_alloc();
define_label("..plt", elf_plt_sect + 1, 0L, NULL, false, false);
elf_sym_sect = seg_alloc();
define_label("..sym", elf_sym_sect + 1, 0L, NULL, false, false);
elf_gottpoff_sect = seg_alloc();
define_label("..gottpoff", elf_gottpoff_sect + 1, 0L, NULL, false, false);
def_seg = seg_alloc();
}
static void elf_cleanup(int debuginfo)
{
struct Reloc *r;
int i;
(void)debuginfo;
elf_write();
for (i = 0; i < nsects; i++) {
if (sects[i]->type != SHT_NOBITS)
saa_free(sects[i]->data);
if (sects[i]->head)
saa_free(sects[i]->rel);
while (sects[i]->head) {
r = sects[i]->head;
sects[i]->head = sects[i]->head->next;
nasm_free(r);
}
}
nasm_free(sects);
saa_free(syms);
raa_free(bsym);
saa_free(strs);
if (of_elfx32.current_dfmt) {
of_elfx32.current_dfmt->cleanup();
}
}
/* add entry to the elf .shstrtab section */
static void add_sectname(char *firsthalf, char *secondhalf)
{
int len = strlen(firsthalf) + strlen(secondhalf);
while (shstrtablen + len + 1 > shstrtabsize)
shstrtab = nasm_realloc(shstrtab, (shstrtabsize += SHSTR_DELTA));
strcpy(shstrtab + shstrtablen, firsthalf);
strcat(shstrtab + shstrtablen, secondhalf);
shstrtablen += len + 1;
}
static int elf_make_section(char *name, int type, int flags, int align)
{
struct Section *s;
s = nasm_zalloc(sizeof(*s));
if (type != SHT_NOBITS)
s->data = saa_init(1L);
s->tail = &s->head;
if (!strcmp(name, ".text"))
s->index = def_seg;
else
s->index = seg_alloc();
add_sectname("", name);
s->name = nasm_strdup(name);
s->type = type;
s->flags = flags;
s->align = align;
if (nsects >= sectlen)
sects = nasm_realloc(sects, (sectlen += SECT_DELTA) * sizeof(*sects));
sects[nsects++] = s;
return nsects - 1;
}
static int32_t elf_section_names(char *name, int pass, int *bits)
{
char *p;
uint32_t flags, flags_and, flags_or;
uint64_t align;
int type, i;
/*
* Default is 64 bits.
*/
if (!name) {
*bits = 64;
return def_seg;
}
p = nasm_skip_word(name);
if (*p)
*p++ = '\0';
flags_and = flags_or = type = align = 0;
section_attrib(name, p, pass, &flags_and,
&flags_or, &align, &type);
if (!strcmp(name, ".shstrtab") ||
!strcmp(name, ".symtab") ||
!strcmp(name, ".strtab")) {
nasm_error(ERR_NONFATAL, "attempt to redefine reserved section"
"name `%s'", name);
return NO_SEG;
}
for (i = 0; i < nsects; i++)
if (!strcmp(name, sects[i]->name))
break;
if (i == nsects) {
const struct elf_known_section *ks = elf_known_sections;
while (ks->name) {
if (!strcmp(name, ks->name))
break;
ks++;
}
type = type ? type : ks->type;
align = align ? align : ks->align;
flags = (ks->flags & ~flags_and) | flags_or;
i = elf_make_section(name, type, flags, align);
} else if (pass == 1) {
if ((type && sects[i]->type != type)
|| (align && sects[i]->align != align)
|| (flags_and && ((sects[i]->flags & flags_and) != flags_or)))
nasm_error(ERR_WARNING, "incompatible section attributes ignored on"
" redeclaration of section `%s'", name);
}
return sects[i]->index;
}
static void elf_deflabel(char *name, int32_t segment, int64_t offset,
int is_global, char *special)
{
int pos = strslen;
struct Symbol *sym;
bool special_used = false;
#if defined(DEBUG) && DEBUG>2
nasm_error(ERR_DEBUG,
" elf_deflabel: %s, seg=%"PRIx32", off=%"PRIx64", is_global=%d, %s\n",
name, segment, offset, is_global, special);
#endif
if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
/*
* This is a NASM special symbol. We never allow it into
* the ELF symbol table, even if it's a valid one. If it
* _isn't_ a valid one, we should barf immediately.
*/
if (strcmp(name, "..gotpc") && strcmp(name, "..gotoff") &&
strcmp(name, "..got") && strcmp(name, "..plt") &&
strcmp(name, "..sym") && strcmp(name, "..gottpoff"))
nasm_error(ERR_NONFATAL, "unrecognised special symbol `%s'", name);
return;
}
if (is_global == 3) {
struct Symbol **s;
/*
* Fix up a forward-reference symbol size from the first
* pass.
*/
for (s = &fwds; *s; s = &(*s)->nextfwd)
if (!strcmp((*s)->name, name)) {
struct tokenval tokval;
expr *e;
char *p = nasm_skip_spaces(nasm_skip_word(special));
stdscan_reset();
stdscan_set(p);
tokval.t_type = TOKEN_INVALID;
e = evaluate(stdscan, NULL, &tokval, NULL, 1, nasm_error, NULL);
if (e) {
if (!is_simple(e))
nasm_error(ERR_NONFATAL, "cannot use relocatable"
" expression as symbol size");
else
(*s)->size = reloc_value(e);
}
/*
* Remove it from the list of unresolved sizes.
*/
nasm_free((*s)->name);
*s = (*s)->nextfwd;
return;
}
return; /* it wasn't an important one */
}
saa_wbytes(strs, name, (int32_t)(1 + strlen(name)));
strslen += 1 + strlen(name);
lastsym = sym = saa_wstruct(syms);
memset(&sym->symv, 0, sizeof(struct rbtree));
sym->strpos = pos;
sym->type = is_global ? SYM_GLOBAL : SYM_LOCAL;
sym->other = STV_DEFAULT;
sym->size = 0;
if (segment == NO_SEG)
sym->section = SHN_ABS;
else {
int i;
sym->section = SHN_UNDEF;
if (segment == def_seg) {
/* we have to be sure at least text section is there */
int tempint;
if (segment != elf_section_names(".text", 2, &tempint))
nasm_error(ERR_PANIC, "strange segment conditions in ELF driver");
}
for (i = 0; i < nsects; i++) {
if (segment == sects[i]->index) {
sym->section = i + 1;
break;
}
}
}
if (is_global == 2) {
sym->size = offset;
sym->symv.key = 0;
sym->section = SHN_COMMON;
/*
* We have a common variable. Check the special text to see
* if it's a valid number and power of two; if so, store it
* as the alignment for the common variable.
*/
if (special) {
bool err;
sym->symv.key = readnum(special, &err);
if (err)
nasm_error(ERR_NONFATAL, "alignment constraint `%s' is not a"
" valid number", special);
else if ((sym->symv.key | (sym->symv.key - 1)) != 2 * sym->symv.key - 1)
nasm_error(ERR_NONFATAL, "alignment constraint `%s' is not a"
" power of two", special);
}
special_used = true;
} else
sym->symv.key = (sym->section == SHN_UNDEF ? 0 : offset);
if (sym->type == SYM_GLOBAL) {
/*
* If sym->section == SHN_ABS, then the first line of the
* else section would cause a core dump, because its a reference
* beyond the end of the section array.
* This behaviour is exhibited by this code:
* GLOBAL crash_nasm
* crash_nasm equ 0
* To avoid such a crash, such requests are silently discarded.
* This may not be the best solution.
*/
if (sym->section == SHN_UNDEF || sym->section == SHN_COMMON) {
bsym = raa_write(bsym, segment, nglobs);
} else if (sym->section != SHN_ABS) {
/*
* This is a global symbol; so we must add it to the rbtree
* of global symbols in its section.
*
* In addition, we check the special text for symbol
* type and size information.
*/
sects[sym->section-1]->gsyms =
rb_insert(sects[sym->section-1]->gsyms, &sym->symv);
if (special) {
int n = strcspn(special, " \t");
if (!nasm_strnicmp(special, "function", n))
sym->type |= STT_FUNC;
else if (!nasm_strnicmp(special, "data", n) ||
!nasm_strnicmp(special, "object", n))
sym->type |= STT_OBJECT;
else if (!nasm_strnicmp(special, "notype", n))
sym->type |= STT_NOTYPE;
else
nasm_error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
n, special);
special += n;
special = nasm_skip_spaces(special);
if (*special) {
n = strcspn(special, " \t");
if (!nasm_strnicmp(special, "default", n))
sym->other = STV_DEFAULT;
else if (!nasm_strnicmp(special, "internal", n))
sym->other = STV_INTERNAL;
else if (!nasm_strnicmp(special, "hidden", n))
sym->other = STV_HIDDEN;
else if (!nasm_strnicmp(special, "protected", n))
sym->other = STV_PROTECTED;
else
n = 0;
special += n;
}
if (*special) {
struct tokenval tokval;
expr *e;
int fwd = 0;
char *saveme = stdscan_get();
while (special[n] && nasm_isspace(special[n]))
n++;
/*
* We have a size expression; attempt to
* evaluate it.
*/
stdscan_reset();
stdscan_set(special + n);
tokval.t_type = TOKEN_INVALID;
e = evaluate(stdscan, NULL, &tokval, &fwd, 0, nasm_error,
NULL);
if (fwd) {
sym->nextfwd = fwds;
fwds = sym;
sym->name = nasm_strdup(name);
} else if (e) {
if (!is_simple(e))
nasm_error(ERR_NONFATAL, "cannot use relocatable"
" expression as symbol size");
else
sym->size = reloc_value(e);
}
stdscan_set(saveme);
}
special_used = true;
}
/*
* If TLS segment, mark symbol accordingly.
*/
if (sects[sym->section - 1]->flags & SHF_TLS) {
sym->type &= 0xf0;
sym->type |= STT_TLS;
}
}
sym->globnum = nglobs;
nglobs++;
} else
nlocals++;
if (special && !special_used)
nasm_error(ERR_NONFATAL, "no special symbol features supported here");
}
static void elf_add_reloc(struct Section *sect, int32_t segment,
int32_t offset, int type)
{
struct Reloc *r;
r = *sect->tail = nasm_zalloc(sizeof(struct Reloc));
sect->tail = &r->next;
r->address = sect->len;
r->offset = offset;
if (segment != NO_SEG) {
int i;
for (i = 0; i < nsects; i++)
if (segment == sects[i]->index)
r->symbol = i + 2;
if (!r->symbol)
r->symbol = GLOBAL_TEMP_BASE + raa_read(bsym, segment);
}
r->type = type;
sect->nrelocs++;
}
/*
* This routine deals with ..got and ..sym relocations: the more
* complicated kinds. In shared-library writing, some relocations
* with respect to global symbols must refer to the precise symbol
* rather than referring to an offset from the base of the section
* _containing_ the symbol. Such relocations call to this routine,
* which searches the symbol list for the symbol in question.
*
* R_X86_64_GOT32 references require the _exact_ symbol address to be
* used; R_X86_64_32 references can be at an offset from the symbol.
* The boolean argument `exact' tells us this.
*
* Return value is the adjusted value of `addr', having become an
* offset from the symbol rather than the section. Should always be
* zero when returning from an exact call.
*
* Limitation: if you define two symbols at the same place,
* confusion will occur.
*
* Inefficiency: we search, currently, using a linked list which
* isn't even necessarily sorted.
*/
static void elf_add_gsym_reloc(struct Section *sect,
int32_t segment, uint32_t offset, int32_t pcrel,
int type, bool exact)
{
struct Reloc *r;
struct Section *s;
struct Symbol *sym;
struct rbtree *srb;
int i;
/*
* First look up the segment/offset pair and find a global
* symbol corresponding to it. If it's not one of our segments,
* then it must be an external symbol, in which case we're fine
* doing a normal elf_add_reloc after first sanity-checking
* that the offset from the symbol is zero.
*/
s = NULL;
for (i = 0; i < nsects; i++)
if (segment == sects[i]->index) {
s = sects[i];
break;
}
if (!s) {
if (exact && offset)
nasm_error(ERR_NONFATAL, "invalid access to an external symbol");
else
elf_add_reloc(sect, segment, offset - pcrel, type);
return;
}
srb = rb_search(s->gsyms, offset);
if (!srb || (exact && srb->key != offset)) {
nasm_error(ERR_NONFATAL, "unable to find a suitable global symbol"
" for this reference");
return;
}
sym = container_of(srb, struct Symbol, symv);
r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
sect->tail = &r->next;
r->next = NULL;
r->address = sect->len;
r->offset = offset - pcrel - sym->symv.key;
r->symbol = GLOBAL_TEMP_BASE + sym->globnum;
r->type = type;
sect->nrelocs++;
}
static void elf_out(int32_t segto, const void *data,
enum out_type type, uint64_t size,
int32_t segment, int32_t wrt)
{
struct Section *s;
int32_t addr;
int reltype, bytes;
int i;
static struct symlininfo sinfo;
#if defined(DEBUG) && DEBUG>2
if (data)
nasm_error(ERR_DEBUG,
" elf_out line: %d type: %x seg: %"PRIx32" segto: %"PRIx32" bytes: %"PRIx64" data: %"PRIx64"\n",
currentline, type, segment, segto, size, *(int64_t *)data);
else
nasm_error(ERR_DEBUG,
" elf_out line: %d type: %x seg: %"PRIx32" segto: %"PRIx32" bytes: %"PRIx64"\n",
currentline, type, segment, segto, size);
#endif
/*
* handle absolute-assembly (structure definitions)
*/
if (segto == NO_SEG) {
if (type != OUT_RESERVE)
nasm_error(ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
" space");
return;
}
s = NULL;
for (i = 0; i < nsects; i++)
if (segto == sects[i]->index) {
s = sects[i];
break;
}
if (!s) {
int tempint; /* ignored */
if (segto != elf_section_names(".text", 2, &tempint))
nasm_error(ERR_PANIC, "strange segment conditions in ELF driver");
else {
s = sects[nsects - 1];
i = nsects - 1;
}
}
/* again some stabs debugging stuff */
if (of_elfx32.current_dfmt) {
sinfo.offset = s->len;
sinfo.section = i;
sinfo.segto = segto;
sinfo.name = s->name;
of_elfx32.current_dfmt->debug_output(TY_DEBUGSYMLIN, &sinfo);
}
/* end of debugging stuff */
if (s->type == SHT_NOBITS && type != OUT_RESERVE) {
nasm_error(ERR_WARNING, "attempt to initialize memory in"
" BSS section `%s': ignored", s->name);
s->len += realsize(type, size);
return;
}
switch (type) {
case OUT_RESERVE:
if (s->type == SHT_PROGBITS) {
nasm_error(ERR_WARNING, "uninitialized space declared in"
" non-BSS section `%s': zeroing", s->name);
elf_sect_write(s, NULL, size);
} else
s->len += size;
break;
case OUT_RAWDATA:
if (segment != NO_SEG)
nasm_error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
elf_sect_write(s, data, size);
break;
case OUT_ADDRESS:
addr = *(int64_t *)data;
if (segment == NO_SEG) {
/* Do nothing */
} else if (segment % 2) {
nasm_error(ERR_NONFATAL, "ELF format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
switch ((int)size) {
case 1:
elf_add_reloc(s, segment, addr, R_X86_64_8);
break;
case 2:
elf_add_reloc(s, segment, addr, R_X86_64_16);
break;
case 4:
elf_add_reloc(s, segment, addr, R_X86_64_32);
break;
case 8:
elf_add_reloc(s, segment, addr, R_X86_64_64);
break;
default:
nasm_error(ERR_PANIC, "internal error elfx32-hpa-871");
break;
}
addr = 0;
} else if (wrt == elf_gotpc_sect + 1) {
/*
* The user will supply GOT relative to $$. ELF
* will let us have GOT relative to $. So we
* need to fix up the data item by $-$$.
*/
addr += s->len;
elf_add_reloc(s, segment, addr, R_X86_64_GOTPC32);
addr = 0;
} else if (wrt == elf_gotoff_sect + 1) {
nasm_error(ERR_NONFATAL, "ELFX32 doesn't support "
"R_X86_64_GOTOFF64");
} else if (wrt == elf_got_sect + 1) {
switch ((int)size) {
case 4:
elf_add_gsym_reloc(s, segment, addr, 0,
R_X86_64_GOT32, true);
addr = 0;
break;
default:
nasm_error(ERR_NONFATAL, "invalid ..got reference");
break;
}
} else if (wrt == elf_sym_sect + 1) {
switch ((int)size) {
case 1:
elf_add_gsym_reloc(s, segment, addr, 0,
R_X86_64_8, false);
addr = 0;
break;
case 2:
elf_add_gsym_reloc(s, segment, addr, 0,
R_X86_64_16, false);
addr = 0;
break;
case 4:
elf_add_gsym_reloc(s, segment, addr, 0,
R_X86_64_32, false);
addr = 0;
break;
case 8:
elf_add_gsym_reloc(s, segment, addr, 0,
R_X86_64_64, false);
addr = 0;
break;
default:
nasm_error(ERR_PANIC, "internal error elfx32-hpa-903");
break;
}
} else if (wrt == elf_plt_sect + 1) {
nasm_error(ERR_NONFATAL, "ELF format cannot produce non-PC-"
"relative PLT references");
} else {
nasm_error(ERR_NONFATAL, "ELF format does not support this"
" use of WRT");
}
}
elf_sect_writeaddr(s, addr, size);
break;
case OUT_REL1ADR:
reltype = R_X86_64_PC8;
bytes = 1;
goto rel12adr;
case OUT_REL2ADR:
reltype = R_X86_64_PC16;
bytes = 2;
goto rel12adr;
rel12adr:
addr = *(int64_t *)data - size;
if (segment == segto)
nasm_error(ERR_PANIC, "intra-segment OUT_REL1ADR");
if (segment == NO_SEG) {
/* Do nothing */
} else if (segment % 2) {
nasm_error(ERR_NONFATAL, "ELF format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
elf_add_reloc(s, segment, addr, reltype);
addr = 0;
} else {
nasm_error(ERR_NONFATAL,
"Unsupported non-32-bit ELF relocation");
}
}
elf_sect_writeaddr(s, addr, bytes);
break;
case OUT_REL4ADR:
addr = *(int64_t *)data - size;
if (segment == segto)
nasm_error(ERR_PANIC, "intra-segment OUT_REL4ADR");
if (segment == NO_SEG) {
/* Do nothing */
} else if (segment % 2) {
nasm_error(ERR_NONFATAL, "ELFX32 format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
elf_add_reloc(s, segment, addr, R_X86_64_PC32);
addr = 0;
} else if (wrt == elf_plt_sect + 1) {
elf_add_gsym_reloc(s, segment, addr+size, size,
R_X86_64_PLT32, true);
addr = 0;
} else if (wrt == elf_gotpc_sect + 1 ||
wrt == elf_got_sect + 1) {
elf_add_gsym_reloc(s, segment, addr+size, size,
R_X86_64_GOTPCREL, true);
addr = 0;
} else if (wrt == elf_gotoff_sect + 1 ||
wrt == elf_got_sect + 1) {
nasm_error(ERR_NONFATAL, "invalid ..gotoff reference");
} else if (wrt == elf_gottpoff_sect + 1) {
elf_add_gsym_reloc(s, segment, addr+size, size,
R_X86_64_GOTTPOFF, true);
addr = 0;
} else {
nasm_error(ERR_NONFATAL, "ELFX32 format does not support this"
" use of WRT");
}
}
elf_sect_writeaddr(s, addr, 4);
break;
case OUT_REL8ADR:
nasm_error(ERR_NONFATAL,
"32-bit ELF format does not support 64-bit relocations");
addr = 0;
elf_sect_writeaddr(s, addr, 8);
break;
}
}
static void elf_write(void)
{
int align;
char *p;
int i;
struct SAA *symtab;
int32_t symtablen, symtablocal;
/*
* Work out how many sections we will have. We have SHN_UNDEF,
* then the flexible user sections, then the fixed sections
* `.shstrtab', `.symtab' and `.strtab', then optionally
* relocation sections for the user sections.
*/
nsections = sec_numspecial + 1;
if (of_elfx32.current_dfmt == &df_stabs)
nsections += 3;
else if (of_elfx32.current_dfmt == &df_dwarf)
nsections += 10;
add_sectname("", ".shstrtab");
add_sectname("", ".symtab");
add_sectname("", ".strtab");
for (i = 0; i < nsects; i++) {
nsections++; /* for the section itself */
if (sects[i]->head) {
nsections++; /* for its relocations */
add_sectname(".rela", sects[i]->name);
}
}
if (of_elfx32.current_dfmt == &df_stabs) {
/* in case the debug information is wanted, just add these three sections... */
add_sectname("", ".stab");
add_sectname("", ".stabstr");
add_sectname(".rel", ".stab");
}
else if (of_elfx32.current_dfmt == &df_dwarf) {
/* the dwarf debug standard specifies the following ten sections,
not all of which are currently implemented,
although all of them are defined. */
add_sectname("", ".debug_aranges");
add_sectname(".rela", ".debug_aranges");
add_sectname("", ".debug_pubnames");
add_sectname("", ".debug_info");
add_sectname(".rela", ".debug_info");
add_sectname("", ".debug_abbrev");
add_sectname("", ".debug_line");
add_sectname(".rela", ".debug_line");
add_sectname("", ".debug_frame");
add_sectname("", ".debug_loc");
}
/*
* Output the ELF header.
*/
fwrite("\177ELF\1\1\1", 7, 1, ofile);
fputc(elf_osabi, ofile);
fputc(elf_abiver, ofile);
fwritezero(7, ofile);
fwriteint16_t(ET_REL, ofile); /* relocatable file */
fwriteint16_t(EM_X86_64, ofile); /* processor ID */
fwriteint32_t(1L, ofile); /* EV_CURRENT file format version */
fwriteint32_t(0L, ofile); /* no entry point */
fwriteint32_t(0L, ofile); /* no program header table */
fwriteint32_t(0x40L, ofile); /* section headers straight after
* ELF header plus alignment */
fwriteint32_t(0L, ofile); /* X86_64 defines no special flags */
fwriteint16_t(0x34, ofile); /* size of ELF header */
fwriteint16_t(0, ofile); /* no program header table, again */
fwriteint16_t(0, ofile); /* still no program header table */
fwriteint16_t(sizeof(Elf32_Shdr), ofile); /* size of section header */
fwriteint16_t(nsections, ofile); /* number of sections */
fwriteint16_t(sec_shstrtab, ofile); /* string table section index for
* section header table */
fwriteint32_t(0L, ofile); /* align to 0x40 bytes */
fwriteint32_t(0L, ofile);
fwriteint32_t(0L, ofile);
/*
* Build the symbol table and relocation tables.
*/
symtab = elf_build_symtab(&symtablen, &symtablocal);
for (i = 0; i < nsects; i++)
if (sects[i]->head)
sects[i]->rel = elf_build_reltab(&sects[i]->rellen,
sects[i]->head);
/*
* Now output the section header table.
*/
elf_foffs = 0x40 + sizeof(Elf32_Shdr) * nsections;
align = ALIGN(elf_foffs, SEC_FILEALIGN) - elf_foffs;
elf_foffs += align;
elf_nsect = 0;
elf_sects = nasm_malloc(sizeof(*elf_sects) * nsections);
/* SHN_UNDEF */
elf_section_header(0, SHT_NULL, 0, NULL, false, 0, SHN_UNDEF, 0, 0, 0);
p = shstrtab + 1;
/* The normal sections */
for (i = 0; i < nsects; i++) {
elf_section_header(p - shstrtab, sects[i]->type, sects[i]->flags,
(sects[i]->type == SHT_PROGBITS ?
sects[i]->data : NULL), true,
sects[i]->len, 0, 0, sects[i]->align, 0);
p += strlen(p) + 1;
}
/* .shstrtab */
elf_section_header(p - shstrtab, SHT_STRTAB, 0, shstrtab, false,
shstrtablen, 0, 0, 1, 0);
p += strlen(p) + 1;
/* .symtab */
elf_section_header(p - shstrtab, SHT_SYMTAB, 0, symtab, true,
symtablen, sec_strtab, symtablocal, 4, 16);
p += strlen(p) + 1;
/* .strtab */
elf_section_header(p - shstrtab, SHT_STRTAB, 0, strs, true,
strslen, 0, 0, 1, 0);
p += strlen(p) + 1;
/* The relocation sections */
for (i = 0; i < nsects; i++)
if (sects[i]->head) {
elf_section_header(p - shstrtab, SHT_RELA, 0, sects[i]->rel, true,
sects[i]->rellen, sec_symtab, i + 1, 4, 12);
p += strlen(p) + 1;
}
if (of_elfx32.current_dfmt == &df_stabs) {
/* for debugging information, create the last three sections
which are the .stab , .stabstr and .rel.stab sections respectively */
/* this function call creates the stab sections in memory */
stabsx32_generate();
if (stabbuf && stabstrbuf && stabrelbuf) {
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, stabbuf, false,
stablen, sec_stabstr, 0, 4, 12);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_STRTAB, 0, stabstrbuf, false,
stabstrlen, 0, 0, 4, 0);
p += strlen(p) + 1;
/* link -> symtable info -> section to refer to */
elf_section_header(p - shstrtab, SHT_REL, 0, stabrelbuf, false,
stabrellen, sec_symtab, sec_stab, 4, 8);
p += strlen(p) + 1;
}
} else if (of_elfx32.current_dfmt == &df_dwarf) {
/* for dwarf debugging information, create the ten dwarf sections */
/* this function call creates the dwarf sections in memory */
if (dwarf_fsect)
dwarfx32_generate();
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, arangesbuf, false,
arangeslen, 0, 0, 1, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_RELA, 0, arangesrelbuf, false,
arangesrellen, sec_symtab, sec_debug_aranges, 1, 12);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, pubnamesbuf, false,
pubnameslen, 0, 0, 1, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, infobuf, false,
infolen, 0, 0, 1, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_RELA, 0, inforelbuf, false,
inforellen, sec_symtab, sec_debug_info, 1, 12);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, abbrevbuf, false,
abbrevlen, 0, 0, 1, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, linebuf, false,
linelen, 0, 0, 1, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_RELA, 0, linerelbuf, false,
linerellen, sec_symtab, sec_debug_line, 1, 12);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, framebuf, false,
framelen, 0, 0, 8, 0);
p += strlen(p) + 1;
elf_section_header(p - shstrtab, SHT_PROGBITS, 0, locbuf, false,
loclen, 0, 0, 1, 0);
p += strlen(p) + 1;
}
fwritezero(align, ofile);
/*
* Now output the sections.
*/
elf_write_sections();
nasm_free(elf_sects);
saa_free(symtab);
}
static struct SAA *elf_build_symtab(int32_t *len, int32_t *local)
{
struct SAA *s = saa_init(1L);
struct Symbol *sym;
uint8_t entry[24], *p;
int i;
*len = *local = 0;
/*
* First, an all-zeros entry, required by the ELF spec.
*/
saa_wbytes(s, NULL, 16L); /* null symbol table entry */
*len += 16;
(*local)++;
/*
* Next, an entry for the file name.
*/
p = entry;
WRITELONG(p, 1); /* we know it's 1st entry in strtab */
WRITELONG(p, 0); /* no value */
WRITELONG(p, 0); /* no size either */
WRITESHORT(p, STT_FILE); /* type FILE */
WRITESHORT(p, SHN_ABS);
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
/*
* Now some standard symbols defining the segments, for relocation
* purposes.
*/
for (i = 1; i <= nsects; i++) {
p = entry;
WRITELONG(p, 0); /* no symbol name */
WRITELONG(p, 0); /* offset zero */
WRITELONG(p, 0); /* size zero */
WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
WRITESHORT(p, i); /* section id */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
}
/*
* Now the other local symbols.
*/
saa_rewind(syms);
while ((sym = saa_rstruct(syms))) {
if (sym->type & SYM_GLOBAL)
continue;
p = entry;
WRITELONG(p, sym->strpos); /* index into symbol string table */
WRITELONG(p, sym->symv.key); /* value of symbol */
WRITELONG(p, sym->size); /* size of symbol */
WRITECHAR(p, sym->type); /* type and binding */
WRITECHAR(p, sym->other); /* visibility */
WRITESHORT(p, sym->section); /* index into section header table */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
}
/*
* dwarf needs symbols for debug sections
* which are relocation targets.
*/
if (of_elfx32.current_dfmt == &df_dwarf) {
dwarf_infosym = *local;
p = entry;
WRITELONG(p, 0); /* no symbol name */
WRITELONG(p, 0); /* offset zero */
WRITELONG(p, 0); /* size zero */
WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
WRITESHORT(p, sec_debug_info); /* section id */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
dwarf_abbrevsym = *local;
p = entry;
WRITELONG(p, 0); /* no symbol name */
WRITELONG(p, 0); /* offset zero */
WRITELONG(p, 0); /* size zero */
WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
WRITESHORT(p, sec_debug_abbrev); /* section id */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
dwarf_linesym = *local;
p = entry;
WRITELONG(p, 0); /* no symbol name */
WRITELONG(p, 0); /* offset zero */
WRITELONG(p, 0); /* size zero */
WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
WRITESHORT(p, sec_debug_line); /* section id */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
}
/*
* Now the global symbols.
*/
saa_rewind(syms);
while ((sym = saa_rstruct(syms))) {
if (!(sym->type & SYM_GLOBAL))
continue;
p = entry;
WRITELONG(p, sym->strpos);
WRITELONG(p, sym->symv.key);
WRITELONG(p, sym->size);
WRITECHAR(p, sym->type); /* type and binding */
WRITECHAR(p, sym->other); /* visibility */
WRITESHORT(p, sym->section);
saa_wbytes(s, entry, 16L);
*len += 16;
}
return s;
}
static struct SAA *elf_build_reltab(uint32_t *len, struct Reloc *r)
{
struct SAA *s;
uint8_t *p, entry[12];
int32_t global_offset;
if (!r)
return NULL;
s = saa_init(1L);
*len = 0;
/*
* How to onvert from a global placeholder to a real symbol index;
* the +2 refers to the two special entries, the null entry and
* the filename entry.
*/
global_offset = -GLOBAL_TEMP_BASE + nsects + nlocals + ndebugs + 2;
while (r) {
int32_t sym = r->symbol;
if (sym >= GLOBAL_TEMP_BASE)
sym += global_offset;
p = entry;
WRITELONG(p, r->address);
WRITELONG(p, (sym << 8) + r->type);
WRITELONG(p, r->offset);
saa_wbytes(s, entry, 12L);
*len += 12;
r = r->next;
}
return s;
}
static void elf_section_header(int name, int type, uint32_t flags,
void *data, bool is_saa, uint32_t datalen,
int link, int info, int align, int eltsize)
{
elf_sects[elf_nsect].data = data;
elf_sects[elf_nsect].len = datalen;
elf_sects[elf_nsect].is_saa = is_saa;
elf_nsect++;
fwriteint32_t((int32_t)name, ofile);
fwriteint32_t((int32_t)type, ofile);
fwriteint32_t((int32_t)flags, ofile);
fwriteint32_t(0L, ofile); /* no address, ever, in object files */
fwriteint32_t(type == 0 ? 0L : elf_foffs, ofile);
fwriteint32_t(datalen, ofile);
if (data)
elf_foffs += ALIGN(datalen, SEC_FILEALIGN);
fwriteint32_t((int32_t)link, ofile);
fwriteint32_t((int32_t)info, ofile);
fwriteint32_t((int32_t)align, ofile);
fwriteint32_t((int32_t)eltsize, ofile);
}
static void elf_write_sections(void)
{
int i;
for (i = 0; i < elf_nsect; i++)
if (elf_sects[i].data) {
int32_t len = elf_sects[i].len;
int32_t reallen = ALIGN(len, SEC_FILEALIGN);
int32_t align = reallen - len;
if (elf_sects[i].is_saa)
saa_fpwrite(elf_sects[i].data, ofile);
else
fwrite(elf_sects[i].data, len, 1, ofile);
fwritezero(align, ofile);
}
}
static void elf_sect_write(struct Section *sect, const void *data, size_t len)
{
saa_wbytes(sect->data, data, len);
sect->len += len;
}
static void elf_sect_writeaddr(struct Section *sect, int32_t data, size_t len)
{
saa_writeaddr(sect->data, data, len);
sect->len += len;
}
static void elf_sectalign(int32_t seg, unsigned int value)
{
struct Section *s = NULL;
int i;
for (i = 0; i < nsects; i++) {
if (sects[i]->index == seg) {
s = sects[i];
break;
}
}
if (!s || !is_power2(value))
return;
if (value > s->align)
s->align = value;
}
static int32_t elf_segbase(int32_t segment)
{
return segment;
}
static int elf_directive(enum directives directive, char *value, int pass)
{
bool err;
int64_t n;
char *p;
switch (directive) {
case D_OSABI:
if (pass == 2)
return 1; /* ignore in pass 2 */
n = readnum(value, &err);
if (err) {
nasm_error(ERR_NONFATAL, "`osabi' directive requires a parameter");
return 1;
}
if (n < 0 || n > 255) {
nasm_error(ERR_NONFATAL, "valid osabi numbers are 0 to 255");
return 1;
}
elf_osabi = n;
elf_abiver = 0;
if ((p = strchr(value,',')) == NULL)
return 1;
n = readnum(p+1, &err);
if (err || n < 0 || n > 255) {
nasm_error(ERR_NONFATAL, "invalid ABI version number (valid: 0 to 255)");
return 1;
}
elf_abiver = n;
return 1;
default:
return 0;
}
}
static void elf_filename(char *inname, char *outname)
{
strcpy(elf_module, inname);
standard_extension(inname, outname, ".o");
}
extern macros_t elf_stdmac[];
static int elf_set_info(enum geninfo type, char **val)
{
(void)type;
(void)val;
return 0;
}
static struct dfmt df_dwarf = {
"ELFX32 (x86-64) dwarf debug format for Linux/Unix",
"dwarf",
dwarfx32_init,
dwarfx32_linenum,
debugx32_deflabel,
debugx32_directive,
debugx32_typevalue,
dwarfx32_output,
dwarfx32_cleanup
};
static struct dfmt df_stabs = {
"ELFX32 (x86-64) stabs debug format for Linux/Unix",
"stabs",
null_debug_init,
stabsx32_linenum,
debugx32_deflabel,
debugx32_directive,
debugx32_typevalue,
stabsx32_output,
stabsx32_cleanup
};
struct dfmt *elfx32_debugs_arr[3] = { &df_dwarf, &df_stabs, NULL };
struct ofmt of_elfx32 = {
"ELFX32 (x86_64) object files (e.g. Linux)",
"elfx32",
0,
elfx32_debugs_arr,
&df_stabs,
elf_stdmac,
elf_init,
elf_set_info,
elf_out,
elf_deflabel,
elf_section_names,
elf_sectalign,
elf_segbase,
elf_directive,
elf_filename,
elf_cleanup
};
/* common debugging routines */
static void debugx32_deflabel(char *name, int32_t segment, int64_t offset,
int is_global, char *special)
{
(void)name;
(void)segment;
(void)offset;
(void)is_global;
(void)special;
}
static void debugx32_directive(const char *directive, const char *params)
{
(void)directive;
(void)params;
}
static void debugx32_typevalue(int32_t type)
{
int32_t stype, ssize;
switch (TYM_TYPE(type)) {
case TY_LABEL:
ssize = 0;
stype = STT_NOTYPE;
break;
case TY_BYTE:
ssize = 1;
stype = STT_OBJECT;
break;
case TY_WORD:
ssize = 2;
stype = STT_OBJECT;
break;
case TY_DWORD:
ssize = 4;
stype = STT_OBJECT;
break;
case TY_FLOAT:
ssize = 4;
stype = STT_OBJECT;
break;
case TY_QWORD:
ssize = 8;
stype = STT_OBJECT;
break;
case TY_TBYTE:
ssize = 10;
stype = STT_OBJECT;
break;
case TY_OWORD:
ssize = 16;
stype = STT_OBJECT;
break;
case TY_YWORD:
ssize = 32;
stype = STT_OBJECT;
break;
case TY_COMMON:
ssize = 0;
stype = STT_COMMON;
break;
case TY_SEG:
ssize = 0;
stype = STT_SECTION;
break;
case TY_EXTERN:
ssize = 0;
stype = STT_NOTYPE;
break;
case TY_EQU:
ssize = 0;
stype = STT_NOTYPE;
break;
default:
ssize = 0;
stype = STT_NOTYPE;
break;
}
if (stype == STT_OBJECT && lastsym && !lastsym->type) {
lastsym->size = ssize;
lastsym->type = stype;
}
}
/* stabs debugging routines */
static void stabsx32_linenum(const char *filename, int32_t linenumber, int32_t segto)
{
(void)segto;
if (!stabs_filename) {
stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
strcpy(stabs_filename, filename);
} else {
if (strcmp(stabs_filename, filename)) {
/* yep, a memory leak...this program is one-shot anyway, so who cares...
in fact, this leak comes in quite handy to maintain a list of files
encountered so far in the symbol lines... */
/* why not nasm_free(stabs_filename); we're done with the old one */
stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
strcpy(stabs_filename, filename);
}
}
debug_immcall = 1;
currentline = linenumber;
}
static void stabsx32_output(int type, void *param)
{
struct symlininfo *s;
struct linelist *el;
if (type == TY_DEBUGSYMLIN) {
if (debug_immcall) {
s = (struct symlininfo *)param;
if (!(sects[s->section]->flags & SHF_EXECINSTR))
return; /* line info is only collected for executable sections */
numlinestabs++;
el = (struct linelist *)nasm_malloc(sizeof(struct linelist));
el->info.offset = s->offset;
el->info.section = s->section;
el->info.name = s->name;
el->line = currentline;
el->filename = stabs_filename;
el->next = 0;
if (stabslines) {
stabslines->last->next = el;
stabslines->last = el;
} else {
stabslines = el;
stabslines->last = el;
}
}
}
debug_immcall = 0;
}
/* for creating the .stab , .stabstr and .rel.stab sections in memory */
static void stabsx32_generate(void)
{
int i, numfiles, strsize, numstabs = 0, currfile, mainfileindex;
uint8_t *sbuf, *ssbuf, *rbuf, *sptr, *rptr;
char **allfiles;
int *fileidx;
struct linelist *ptr;
ptr = stabslines;
allfiles = (char **)nasm_zalloc(numlinestabs * sizeof(char *));
numfiles = 0;
while (ptr) {
if (numfiles == 0) {
allfiles[0] = ptr->filename;
numfiles++;
} else {
for (i = 0; i < numfiles; i++) {
if (!strcmp(allfiles[i], ptr->filename))
break;
}
if (i >= numfiles) {
allfiles[i] = ptr->filename;
numfiles++;
}
}
ptr = ptr->next;
}
strsize = 1;
fileidx = (int *)nasm_malloc(numfiles * sizeof(int));
for (i = 0; i < numfiles; i++) {
fileidx[i] = strsize;
strsize += strlen(allfiles[i]) + 1;
}
mainfileindex = 0;
for (i = 0; i < numfiles; i++) {
if (!strcmp(allfiles[i], elf_module)) {
mainfileindex = i;
break;
}
}
/*
* worst case size of the stab buffer would be:
* the sourcefiles changes each line, which would mean 1 SOL, 1 SYMLIN per line
* plus one "ending" entry
*/
sbuf = (uint8_t *)nasm_malloc((numlinestabs * 2 + 4) *
sizeof(struct stabentry));
ssbuf = (uint8_t *)nasm_malloc(strsize);
rbuf = (uint8_t *)nasm_malloc(numlinestabs * 8 * (2 + 3));
rptr = rbuf;
for (i = 0; i < numfiles; i++)
strcpy((char *)ssbuf + fileidx[i], allfiles[i]);
ssbuf[0] = 0;
stabstrlen = strsize; /* set global variable for length of stab strings */
sptr = sbuf;
ptr = stabslines;
numstabs = 0;
if (ptr) {
/*
* this is the first stab, its strx points to the filename of the
* the source-file, the n_desc field should be set to the number
* of remaining stabs
*/
WRITE_STAB(sptr, fileidx[0], 0, 0, 0, strlen(allfiles[0] + 12));
/* this is the stab for the main source file */
WRITE_STAB(sptr, fileidx[mainfileindex], N_SO, 0, 0, 0);
/* relocation table entry */
/*
* Since the symbol table has two entries before
* the section symbols, the index in the info.section
* member must be adjusted by adding 2
*/
WRITELONG(rptr, (sptr - sbuf) - 4);
WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_X86_64_32);
numstabs++;
currfile = mainfileindex;
}
while (ptr) {
if (strcmp(allfiles[currfile], ptr->filename)) {
/* oops file has changed... */
for (i = 0; i < numfiles; i++)
if (!strcmp(allfiles[i], ptr->filename))
break;
currfile = i;
WRITE_STAB(sptr, fileidx[currfile], N_SOL, 0, 0,
ptr->info.offset);
numstabs++;
/* relocation table entry */
WRITELONG(rptr, (sptr - sbuf) - 4);
WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_X86_64_32);
}
WRITE_STAB(sptr, 0, N_SLINE, 0, ptr->line, ptr->info.offset);
numstabs++;
/* relocation table entry */
WRITELONG(rptr, (sptr - sbuf) - 4);
WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_X86_64_32);
ptr = ptr->next;
}
/* this is an "ending" token */
WRITE_STAB(sptr, 0, N_SO, 0, 0, 0);
numstabs++;
((struct stabentry *)sbuf)->n_desc = numstabs;
nasm_free(allfiles);
nasm_free(fileidx);
stablen = (sptr - sbuf);
stabrellen = (rptr - rbuf);
stabrelbuf = rbuf;
stabbuf = sbuf;
stabstrbuf = ssbuf;
}
static void stabsx32_cleanup(void)
{
struct linelist *ptr, *del;
if (!stabslines)
return;
ptr = stabslines;
while (ptr) {
del = ptr;
ptr = ptr->next;
nasm_free(del);
}
nasm_free(stabbuf);
nasm_free(stabrelbuf);
nasm_free(stabstrbuf);
}
/* dwarf routines */
static void dwarfx32_init(void)
{
ndebugs = 3; /* 3 debug symbols */
}
static void dwarfx32_linenum(const char *filename, int32_t linenumber,
int32_t segto)
{
(void)segto;
dwarfx32_findfile(filename);
debug_immcall = 1;
currentline = linenumber;
}
/* called from elf_out with type == TY_DEBUGSYMLIN */
static void dwarfx32_output(int type, void *param)
{
int ln, aa, inx, maxln, soc;
struct symlininfo *s;
struct SAA *plinep;
(void)type;
s = (struct symlininfo *)param;
/* line number info is only gathered for executable sections */
if (!(sects[s->section]->flags & SHF_EXECINSTR))
return;
/* Check if section index has changed */
if (!(dwarf_csect && (dwarf_csect->section) == (s->section)))
dwarfx32_findsect(s->section);
/* do nothing unless line or file has changed */
if (!debug_immcall)
return;
ln = currentline - dwarf_csect->line;
aa = s->offset - dwarf_csect->offset;
inx = dwarf_clist->line;
plinep = dwarf_csect->psaa;
/* check for file change */
if (!(inx == dwarf_csect->file)) {
saa_write8(plinep,DW_LNS_set_file);
saa_write8(plinep,inx);
dwarf_csect->file = inx;
}
/* check for line change */
if (ln) {
/* test if in range of special op code */
maxln = line_base + line_range;
soc = (ln - line_base) + (line_range * aa) + opcode_base;
if (ln >= line_base && ln < maxln && soc < 256) {
saa_write8(plinep,soc);
} else {
saa_write8(plinep,DW_LNS_advance_line);
saa_wleb128s(plinep,ln);
if (aa) {
saa_write8(plinep,DW_LNS_advance_pc);
saa_wleb128u(plinep,aa);
}
}
dwarf_csect->line = currentline;
dwarf_csect->offset = s->offset;
}
/* show change handled */
debug_immcall = 0;
}
static void dwarfx32_generate(void)
{
uint8_t *pbuf;
int indx;
struct linelist *ftentry;
struct SAA *paranges, *ppubnames, *pinfo, *pabbrev, *plines, *plinep;
struct SAA *parangesrel, *plinesrel, *pinforel;
struct sectlist *psect;
size_t saalen, linepoff, totlen, highaddr;
/* write epilogues for each line program range */
/* and build aranges section */
paranges = saa_init(1L);
parangesrel = saa_init(1L);
saa_write16(paranges,3); /* dwarf version */
saa_write32(parangesrel, paranges->datalen+4);
saa_write32(parangesrel, (dwarf_infosym << 8) + R_X86_64_32); /* reloc to info */
saa_write32(parangesrel, 0);
saa_write32(paranges,0); /* offset into info */
saa_write8(paranges,4); /* pointer size */
saa_write8(paranges,0); /* not segmented */
saa_write32(paranges,0); /* padding */
/* iterate though sectlist entries */
psect = dwarf_fsect;
totlen = 0;
highaddr = 0;
for (indx = 0; indx < dwarf_nsections; indx++)
{
plinep = psect->psaa;
/* Line Number Program Epilogue */
saa_write8(plinep,2); /* std op 2 */
saa_write8(plinep,(sects[psect->section]->len)-psect->offset);
saa_write8(plinep,DW_LNS_extended_op);
saa_write8(plinep,1); /* operand length */
saa_write8(plinep,DW_LNE_end_sequence);
totlen += plinep->datalen;
/* range table relocation entry */
saa_write32(parangesrel, paranges->datalen + 4);
saa_write32(parangesrel, ((uint32_t) (psect->section + 2) << 8) + R_X86_64_32);
saa_write32(parangesrel, (uint32_t) 0);
/* range table entry */
saa_write32(paranges,0x0000); /* range start */
saa_write32(paranges,sects[psect->section]->len); /* range length */
highaddr += sects[psect->section]->len;
/* done with this entry */
psect = psect->next;
}
saa_write32(paranges,0); /* null address */
saa_write32(paranges,0); /* null length */
saalen = paranges->datalen;
arangeslen = saalen + 4;
arangesbuf = pbuf = nasm_malloc(arangeslen);
WRITELONG(pbuf,saalen); /* initial length */
saa_rnbytes(paranges, pbuf, saalen);
saa_free(paranges);
/* build rela.aranges section */
arangesrellen = saalen = parangesrel->datalen;
arangesrelbuf = pbuf = nasm_malloc(arangesrellen);
saa_rnbytes(parangesrel, pbuf, saalen);
saa_free(parangesrel);
/* build pubnames section */
ppubnames = saa_init(1L);
saa_write16(ppubnames,3); /* dwarf version */
saa_write32(ppubnames,0); /* offset into info */
saa_write32(ppubnames,0); /* space used in info */
saa_write32(ppubnames,0); /* end of list */
saalen = ppubnames->datalen;
pubnameslen = saalen + 4;
pubnamesbuf = pbuf = nasm_malloc(pubnameslen);
WRITELONG(pbuf,saalen); /* initial length */
saa_rnbytes(ppubnames, pbuf, saalen);
saa_free(ppubnames);
/* build info section */
pinfo = saa_init(1L);
pinforel = saa_init(1L);
saa_write16(pinfo,3); /* dwarf version */
saa_write32(pinforel, pinfo->datalen + 4);
saa_write32(pinforel, (dwarf_abbrevsym << 8) + R_X86_64_32); /* reloc to abbrev */
saa_write32(pinforel, 0);
saa_write32(pinfo,0); /* offset into abbrev */
saa_write8(pinfo,4); /* pointer size */
saa_write8(pinfo,1); /* abbrviation number LEB128u */
saa_write32(pinforel, pinfo->datalen + 4);
saa_write32(pinforel, ((dwarf_fsect->section + 2) << 8) + R_X86_64_32);
saa_write32(pinforel, 0);
saa_write32(pinfo,0); /* DW_AT_low_pc */
saa_write32(pinforel, pinfo->datalen + 4);
saa_write32(pinforel, ((dwarf_fsect->section + 2) << 8) + R_X86_64_32);
saa_write32(pinforel, 0);
saa_write32(pinfo,highaddr); /* DW_AT_high_pc */
saa_write32(pinforel, pinfo->datalen + 4);
saa_write32(pinforel, (dwarf_linesym << 8) + R_X86_64_32); /* reloc to line */
saa_write32(pinforel, 0);
saa_write32(pinfo,0); /* DW_AT_stmt_list */
saa_wbytes(pinfo, elf_module, strlen(elf_module)+1);
saa_wbytes(pinfo, nasm_signature, strlen(nasm_signature)+1);
saa_write16(pinfo,DW_LANG_Mips_Assembler);
saa_write8(pinfo,2); /* abbrviation number LEB128u */
saa_write32(pinforel, pinfo->datalen + 4);
saa_write32(pinforel, ((dwarf_fsect->section + 2) << 8) + R_X86_64_32);
saa_write32(pinforel, 0);
saa_write32(pinfo,0); /* DW_AT_low_pc */
saa_write32(pinfo,0); /* DW_AT_frame_base */
saa_write8(pinfo,0); /* end of entries */
saalen = pinfo->datalen;
infolen = saalen + 4;
infobuf = pbuf = nasm_malloc(infolen);
WRITELONG(pbuf,saalen); /* initial length */
saa_rnbytes(pinfo, pbuf, saalen);
saa_free(pinfo);
/* build rela.info section */
inforellen = saalen = pinforel->datalen;
inforelbuf = pbuf = nasm_malloc(inforellen);
saa_rnbytes(pinforel, pbuf, saalen);
saa_free(pinforel);
/* build abbrev section */
pabbrev = saa_init(1L);
saa_write8(pabbrev,1); /* entry number LEB128u */
saa_write8(pabbrev,DW_TAG_compile_unit); /* tag LEB128u */
saa_write8(pabbrev,1); /* has children */
/* the following attributes and forms are all LEB128u values */
saa_write8(pabbrev,DW_AT_low_pc);
saa_write8(pabbrev,DW_FORM_addr);
saa_write8(pabbrev,DW_AT_high_pc);
saa_write8(pabbrev,DW_FORM_addr);
saa_write8(pabbrev,DW_AT_stmt_list);
saa_write8(pabbrev,DW_FORM_data4);
saa_write8(pabbrev,DW_AT_name);
saa_write8(pabbrev,DW_FORM_string);
saa_write8(pabbrev,DW_AT_producer);
saa_write8(pabbrev,DW_FORM_string);
saa_write8(pabbrev,DW_AT_language);
saa_write8(pabbrev,DW_FORM_data2);
saa_write16(pabbrev,0); /* end of entry */
/* LEB128u usage same as above */
saa_write8(pabbrev,2); /* entry number */
saa_write8(pabbrev,DW_TAG_subprogram);
saa_write8(pabbrev,0); /* no children */
saa_write8(pabbrev,DW_AT_low_pc);
saa_write8(pabbrev,DW_FORM_addr);
saa_write8(pabbrev,DW_AT_frame_base);
saa_write8(pabbrev,DW_FORM_data4);
saa_write16(pabbrev,0); /* end of entry */
abbrevlen = saalen = pabbrev->datalen;
abbrevbuf = pbuf = nasm_malloc(saalen);
saa_rnbytes(pabbrev, pbuf, saalen);
saa_free(pabbrev);
/* build line section */
/* prolog */
plines = saa_init(1L);
saa_write8(plines,1); /* Minimum Instruction Length */
saa_write8(plines,1); /* Initial value of 'is_stmt' */
saa_write8(plines,line_base); /* Line Base */
saa_write8(plines,line_range); /* Line Range */
saa_write8(plines,opcode_base); /* Opcode Base */
/* standard opcode lengths (# of LEB128u operands) */
saa_write8(plines,0); /* Std opcode 1 length */
saa_write8(plines,1); /* Std opcode 2 length */
saa_write8(plines,1); /* Std opcode 3 length */
saa_write8(plines,1); /* Std opcode 4 length */
saa_write8(plines,1); /* Std opcode 5 length */
saa_write8(plines,0); /* Std opcode 6 length */
saa_write8(plines,0); /* Std opcode 7 length */
saa_write8(plines,0); /* Std opcode 8 length */
saa_write8(plines,1); /* Std opcode 9 length */
saa_write8(plines,0); /* Std opcode 10 length */
saa_write8(plines,0); /* Std opcode 11 length */
saa_write8(plines,1); /* Std opcode 12 length */
/* Directory Table */
saa_write8(plines,0); /* End of table */
/* File Name Table */
ftentry = dwarf_flist;
for (indx = 0;indx<dwarf_numfiles;indx++)
{
saa_wbytes(plines, ftentry->filename, (int32_t)(strlen(ftentry->filename) + 1));
saa_write8(plines,0); /* directory LEB128u */
saa_write8(plines,0); /* time LEB128u */
saa_write8(plines,0); /* size LEB128u */
ftentry = ftentry->next;
}
saa_write8(plines,0); /* End of table */
linepoff = plines->datalen;
linelen = linepoff + totlen + 10;
linebuf = pbuf = nasm_malloc(linelen);
WRITELONG(pbuf,linelen-4); /* initial length */
WRITESHORT(pbuf,3); /* dwarf version */
WRITELONG(pbuf,linepoff); /* offset to line number program */
/* write line header */
saalen = linepoff;
saa_rnbytes(plines, pbuf, saalen); /* read a given no. of bytes */
pbuf += linepoff;
saa_free(plines);
/* concatonate line program ranges */
linepoff += 13;
plinesrel = saa_init(1L);
psect = dwarf_fsect;
for (indx = 0; indx < dwarf_nsections; indx++) {
saa_write32(plinesrel, linepoff);
saa_write32(plinesrel, ((psect->section + 2) << 8) + R_X86_64_32);
saa_write32(plinesrel, 0);
plinep = psect->psaa;
saalen = plinep->datalen;
saa_rnbytes(plinep, pbuf, saalen);
pbuf += saalen;
linepoff += saalen;
saa_free(plinep);
/* done with this entry */
psect = psect->next;
}
/* build rela.lines section */
linerellen =saalen = plinesrel->datalen;
linerelbuf = pbuf = nasm_malloc(linerellen);
saa_rnbytes(plinesrel, pbuf, saalen);
saa_free(plinesrel);
/* build frame section */
framelen = 4;
framebuf = pbuf = nasm_malloc(framelen);
WRITELONG(pbuf,framelen-4); /* initial length */
/* build loc section */
loclen = 16;
locbuf = pbuf = nasm_malloc(loclen);
WRITELONG(pbuf,0); /* null beginning offset */
WRITELONG(pbuf,0); /* null ending offset */
}
static void dwarfx32_cleanup(void)
{
nasm_free(arangesbuf);
nasm_free(arangesrelbuf);
nasm_free(pubnamesbuf);
nasm_free(infobuf);
nasm_free(inforelbuf);
nasm_free(abbrevbuf);
nasm_free(linebuf);
nasm_free(linerelbuf);
nasm_free(framebuf);
nasm_free(locbuf);
}
static void dwarfx32_findfile(const char * fname)
{
int finx;
struct linelist *match;
/* return if fname is current file name */
if (dwarf_clist && !(strcmp(fname, dwarf_clist->filename)))
return;
/* search for match */
match = 0;
if (dwarf_flist) {
match = dwarf_flist;
for (finx = 0; finx < dwarf_numfiles; finx++) {
if (!(strcmp(fname, match->filename))) {
dwarf_clist = match;
return;
}
}
}
/* add file name to end of list */
dwarf_clist = (struct linelist *)nasm_malloc(sizeof(struct linelist));
dwarf_numfiles++;
dwarf_clist->line = dwarf_numfiles;
dwarf_clist->filename = nasm_malloc(strlen(fname) + 1);
strcpy(dwarf_clist->filename,fname);
dwarf_clist->next = 0;
if (!dwarf_flist) { /* if first entry */
dwarf_flist = dwarf_elist = dwarf_clist;
dwarf_clist->last = 0;
} else { /* chain to previous entry */
dwarf_elist->next = dwarf_clist;
dwarf_elist = dwarf_clist;
}
}
static void dwarfx32_findsect(const int index)
{
int sinx;
struct sectlist *match;
struct SAA *plinep;
/* return if index is current section index */
if (dwarf_csect && (dwarf_csect->section == index))
return;
/* search for match */
match = 0;
if (dwarf_fsect) {
match = dwarf_fsect;
for (sinx = 0; sinx < dwarf_nsections; sinx++) {
if ((match->section == index)) {
dwarf_csect = match;
return;
}
match = match->next;
}
}
/* add entry to end of list */
dwarf_csect = (struct sectlist *)nasm_malloc(sizeof(struct sectlist));
dwarf_nsections++;
dwarf_csect->psaa = plinep = saa_init(1L);
dwarf_csect->line = 1;
dwarf_csect->offset = 0;
dwarf_csect->file = 1;
dwarf_csect->section = index;
dwarf_csect->next = 0;
/* set relocatable address at start of line program */
saa_write8(plinep,DW_LNS_extended_op);
saa_write8(plinep,5); /* operand length */
saa_write8(plinep,DW_LNE_set_address);
saa_write32(plinep,0); /* Start Address */
if (!dwarf_fsect) { /* if first entry */
dwarf_fsect = dwarf_esect = dwarf_csect;
dwarf_csect->last = 0;
} else { /* chain to previous entry */
dwarf_esect->next = dwarf_csect;
dwarf_esect = dwarf_csect;
}
}
#endif /* OF_ELFX32 */
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