int
archreloc(Reloc *r, Sym *s, vlong *val)
{
USED(s);
switch(r->type) {
case D_CONST:
*val = r->add;
return 0;
case D_GOTOFF:
*val = symaddr(r->sym) + r->add - symaddr(lookup(".got", 0));
return 0;
}
return -1;
}
void
shsym(Elf64_Shdr *sh, Sym *s)
{
sh->addr = symaddr(s);
sh->off = datoff(sh->addr);
sh->size = s->size;
}
int
archreloc(Reloc *r, LSym *s, vlong *val)
{
USED(s);
if(linkmode == LinkExternal)
return -1;
switch(r->type) {
case D_CONST:
*val = r->add;
return 0;
case D_GOTOFF:
*val = symaddr(r->sym) + r->add - symaddr(linklookup(ctxt, ".got", 0));
return 0;
}
return -1;
}
void
shsym(ElfShdr *sh, Sym *s)
{
vlong addr;
addr = symaddr(s);
if(sh->flags&SHF_ALLOC)
sh->addr = addr;
sh->off = datoff(addr);
sh->size = s->size;
}
void
relocsym(Sym *s)
{
Reloc *r;
Prog p;
int32 i, off, siz, fl;
vlong o;
uchar *cast;
cursym = s;
memset(&p, 0, sizeof p);
for(r=s->r; r<s->r+s->nr; r++) {
off = r->off;
siz = r->siz;
if(off < 0 || off+(siz&~Rbig) > s->np) {
diag("%s: invalid relocation %d+%d not in [%d,%d)", s->name, off, siz&~Rbig, 0, s->np);
continue;
}
if(r->sym != S && (r->sym->type == 0 || r->sym->type == SXREF)) {
diag("%s: not defined", r->sym->name);
continue;
}
if(r->type >= 256)
continue;
if(r->sym != S && r->sym->type == SDYNIMPORT)
diag("unhandled relocation for %s (type %d rtype %d)", r->sym->name, r->sym->type, r->type);
if(r->sym != S && !r->sym->reachable)
diag("unreachable sym in relocation: %s %s", s->name, r->sym->name);
switch(r->type) {
default:
o = 0;
if(archreloc(r, s, &o) < 0)
diag("unknown reloc %d", r->type);
break;
case D_ADDR:
o = symaddr(r->sym) + r->add;
break;
case D_PCREL:
// r->sym can be null when CALL $(constant) is transformed from absoulte PC to relative PC call.
o = 0;
if(r->sym)
o += symaddr(r->sym);
o += r->add - (s->value + r->off + r->siz);
break;
case D_SIZE:
o = r->sym->size + r->add;
break;
}
//print("relocate %s %p %s => %p %p %p %p [%p]\n", s->name, s->value+off, r->sym ? r->sym->name : "<nil>", (void*)symaddr(r->sym), (void*)s->value, (void*)r->off, (void*)r->siz, (void*)o);
switch(siz) {
default:
cursym = s;
diag("bad reloc size %#ux for %s", siz, r->sym->name);
case 4 + Rbig:
fl = o;
s->p[off] = fl>>24;
s->p[off+1] = fl>>16;
s->p[off+2] = fl>>8;
s->p[off+3] = fl;
break;
case 4 + Rlittle:
fl = o;
s->p[off] = fl;
s->p[off+1] = fl>>8;
s->p[off+2] = fl>>16;
s->p[off+3] = fl>>24;
break;
case 4:
fl = o;
cast = (uchar*)&fl;
for(i=0; i<4; i++)
s->p[off+i] = cast[inuxi4[i]];
break;
case 8:
cast = (uchar*)&o;
for(i=0; i<8; i++)
s->p[off+i] = cast[inuxi8[i]];
break;
}
}
}
void
genasmsym(void (*put)(Sym*, char*, int, vlong, vlong, int, Sym*))
{
Auto *a;
Sym *s;
int h;
s = lookup("etext", 0);
if(s->type == STEXT)
put(s, s->name, 'T', s->value, s->size, s->version, 0);
for(h=0; h<NHASH; h++) {
for(s=hash[h]; s!=S; s=s->hash) {
if(s->hide)
continue;
switch(s->type&SMASK) {
case SCONST:
case SRODATA:
case SDATA:
case SELFROSECT:
case SMACHO:
case SMACHOGOT:
case STYPE:
case SSTRING:
case SGOSTRING:
case SWINDOWS:
case SNOPTRDATA:
case SSYMTAB:
case SPCLNTAB:
case SGCDATA:
case SGCBSS:
if(!s->reachable)
continue;
put(s, s->name, 'D', symaddr(s), s->size, s->version, s->gotype);
continue;
case SBSS:
case SNOPTRBSS:
if(!s->reachable)
continue;
put(s, s->name, 'B', symaddr(s), s->size, s->version, s->gotype);
continue;
case SFILE:
put(nil, s->name, 'f', s->value, 0, s->version, 0);
continue;
}
}
}
for(s = textp; s != nil; s = s->next) {
if(s->text == nil)
continue;
/* filenames first */
for(a=s->autom; a; a=a->link)
if(a->type == D_FILE)
put(nil, a->asym->name, 'z', a->aoffset, 0, 0, 0);
else if(a->type == D_FILE1)
put(nil, a->asym->name, 'Z', a->aoffset, 0, 0, 0);
put(s, s->name, 'T', s->value, s->size, s->version, s->gotype);
/* frame, auto and param after */
put(nil, ".frame", 'm', s->text->to.offset+4, 0, 0, 0);
for(a=s->autom; a; a=a->link)
if(a->type == D_AUTO)
put(nil, a->asym->name, 'a', -a->aoffset, 0, 0, a->gotype);
else if(a->type == D_PARAM)
put(nil, a->asym->name, 'p', a->aoffset, 0, 0, a->gotype);
}
if(debug['v'] || debug['n'])
Bprint(&bso, "symsize = %d\n", symsize);
Bflush(&bso);
}
void
relocsym(Sym *s)
{
Reloc *r;
Sym *rs;
Prog p;
int32 i, off, siz, fl;
vlong o;
uchar *cast;
cursym = s;
memset(&p, 0, sizeof p);
for(r=s->r; r<s->r+s->nr; r++) {
r->done = 1;
off = r->off;
siz = r->siz;
if(off < 0 || off+siz > s->np) {
diag("%s: invalid relocation %d+%d not in [%d,%d)", s->name, off, siz, 0, s->np);
continue;
}
if(r->sym != S && (r->sym->type & SMASK == 0 || r->sym->type & SMASK == SXREF)) {
diag("%s: not defined", r->sym->name);
continue;
}
if(r->type >= 256)
continue;
if(r->sym != S && r->sym->type == SDYNIMPORT)
diag("unhandled relocation for %s (type %d rtype %d)", r->sym->name, r->sym->type, r->type);
if(r->sym != S && !r->sym->reachable)
diag("unreachable sym in relocation: %s %s", s->name, r->sym->name);
switch(r->type) {
default:
o = 0;
if(linkmode == LinkExternal || archreloc(r, s, &o) < 0)
diag("unknown reloc %d", r->type);
break;
case D_ADDR:
if(linkmode == LinkExternal && r->sym->type != SCONST) {
r->done = 0;
// set up addend for eventual relocation via outer symbol.
rs = r->sym;
r->xadd = r->add;
while(rs->outer != nil) {
r->xadd += symaddr(rs) - symaddr(rs->outer);
rs = rs->outer;
}
if(rs->type != SHOSTOBJ && rs->sect == nil)
diag("missing section for %s", rs->name);
r->xsym = rs;
o = r->xadd;
if(iself) {
if(thechar == '6')
o = 0;
} else if(HEADTYPE == Hdarwin) {
if(rs->type != SHOSTOBJ)
o += symaddr(rs);
} else {
diag("unhandled pcrel relocation for %s", headtype);
}
break;
}
o = symaddr(r->sym) + r->add;
break;
case D_PCREL:
// r->sym can be null when CALL $(constant) is transformed from absolute PC to relative PC call.
if(linkmode == LinkExternal && r->sym && r->sym->type != SCONST && r->sym->sect != cursym->sect) {
r->done = 0;
// set up addend for eventual relocation via outer symbol.
rs = r->sym;
r->xadd = r->add;
while(rs->outer != nil) {
r->xadd += symaddr(rs) - symaddr(rs->outer);
rs = rs->outer;
}
r->xadd -= r->siz; // relative to address after the relocated chunk
if(rs->type != SHOSTOBJ && rs->sect == nil)
diag("missing section for %s", rs->name);
r->xsym = rs;
o = r->xadd;
if(iself) {
if(thechar == '6')
o = 0;
} else if(HEADTYPE == Hdarwin) {
if(rs->type != SHOSTOBJ)
o += symaddr(rs) - rs->sect->vaddr;
o -= r->off; // WTF?
} else {
diag("unhandled pcrel relocation for %s", headtype);
}
break;
}
o = 0;
if(r->sym)
o += symaddr(r->sym);
o += r->add - (s->value + r->off + r->siz);
break;
case D_SIZE:
o = r->sym->size + r->add;
break;
}
//print("relocate %s %p %s => %p %p %p %p [%p]\n", s->name, s->value+off, r->sym ? r->sym->name : "<nil>", (void*)symaddr(r->sym), (void*)s->value, (void*)r->off, (void*)r->siz, (void*)o);
switch(siz) {
default:
cursym = s;
diag("bad reloc size %#ux for %s", siz, r->sym->name);
case 4:
fl = o;
cast = (uchar*)&fl;
for(i=0; i<4; i++)
s->p[off+i] = cast[inuxi4[i]];
break;
case 8:
cast = (uchar*)&o;
for(i=0; i<8; i++)
s->p[off+i] = cast[inuxi8[i]];
break;
}
}
}
// assign addresses
void
address(void)
{
Section *s, *text, *data, *rodata, *symtab, *pclntab, *noptr, *bss, *noptrbss, *datarelro;
Section *typelink;
Sym *sym, *sub;
uvlong va;
vlong vlen;
va = INITTEXT;
segtext.rwx = 05;
segtext.vaddr = va;
segtext.fileoff = HEADR;
for(s=segtext.sect; s != nil; s=s->next) {
va = rnd(va, s->align);
s->vaddr = va;
va += s->len;
}
segtext.len = va - INITTEXT;
segtext.filelen = segtext.len;
va = rnd(va, INITRND);
segdata.rwx = 06;
segdata.vaddr = va;
segdata.fileoff = va - segtext.vaddr + segtext.fileoff;
segdata.filelen = 0;
if(HEADTYPE == Hwindows)
segdata.fileoff = segtext.fileoff + rnd(segtext.len, PEFILEALIGN);
if(HEADTYPE == Hplan9x64 || HEADTYPE == Hplan9x32)
segdata.fileoff = segtext.fileoff + segtext.filelen;
data = nil;
noptr = nil;
bss = nil;
noptrbss = nil;
datarelro = nil;
for(s=segdata.sect; s != nil; s=s->next) {
vlen = s->len;
if(s->next)
vlen = s->next->vaddr - s->vaddr;
s->vaddr = va;
va += vlen;
segdata.len = va - segdata.vaddr;
if(strcmp(s->name, ".data") == 0)
data = s;
if(strcmp(s->name, ".noptrdata") == 0)
noptr = s;
if(strcmp(s->name, ".bss") == 0)
bss = s;
if(strcmp(s->name, ".noptrbss") == 0)
noptrbss = s;
if(strcmp(s->name, ".data.rel.ro") == 0)
datarelro = s;
}
segdata.filelen = bss->vaddr - segdata.vaddr;
text = segtext.sect;
rodata = text->next;
typelink = rodata->next;
symtab = typelink->next;
pclntab = symtab->next;
for(sym = datap; sym != nil; sym = sym->next) {
cursym = sym;
if(sym->type < SNOPTRDATA)
sym->value += rodata->vaddr;
else
sym->value += segdata.sect->vaddr;
for(sub = sym->sub; sub != nil; sub = sub->sub)
sub->value += sym->value;
}
xdefine("text", STEXT, text->vaddr);
xdefine("etext", STEXT, text->vaddr + text->len);
xdefine("rodata", SRODATA, rodata->vaddr);
xdefine("erodata", SRODATA, rodata->vaddr + rodata->len);
xdefine("typelink", SRODATA, typelink->vaddr);
xdefine("etypelink", SRODATA, typelink->vaddr + typelink->len);
if(datarelro != nil) {
xdefine("datarelro", SRODATA, datarelro->vaddr);
xdefine("edatarelro", SRODATA, datarelro->vaddr + datarelro->len);
}
sym = lookup("gcdata", 0);
xdefine("egcdata", STYPE, symaddr(sym) + sym->size);
lookup("egcdata", 0)->sect = sym->sect;
sym = lookup("gcbss", 0);
xdefine("egcbss", STYPE, symaddr(sym) + sym->size);
lookup("egcbss", 0)->sect = sym->sect;
xdefine("symtab", SRODATA, symtab->vaddr);
xdefine("esymtab", SRODATA, symtab->vaddr + symtab->len);
xdefine("pclntab", SRODATA, pclntab->vaddr);
xdefine("epclntab", SRODATA, pclntab->vaddr + pclntab->len);
xdefine("noptrdata", SNOPTRDATA, noptr->vaddr);
xdefine("enoptrdata", SNOPTRDATA, noptr->vaddr + noptr->len);
xdefine("bss", SBSS, bss->vaddr);
xdefine("ebss", SBSS, bss->vaddr + bss->len);
xdefine("data", SDATA, data->vaddr);
xdefine("edata", SDATA, data->vaddr + data->len);
xdefine("noptrbss", SNOPTRBSS, noptrbss->vaddr);
xdefine("enoptrbss", SNOPTRBSS, noptrbss->vaddr + noptrbss->len);
xdefine("end", SBSS, segdata.vaddr + segdata.len);
}
void
relocsym(Sym *s)
{
Reloc *r;
Sym *rs;
Prog p;
int32 i, off, siz, fl;
vlong o;
uchar *cast;
cursym = s;
memset(&p, 0, sizeof p);
for(r=s->r; r<s->r+s->nr; r++) {
off = r->off;
siz = r->siz;
if(off < 0 || off+siz > s->np) {
diag("%s: invalid relocation %d+%d not in [%d,%d)", s->name, off, siz, 0, s->np);
continue;
}
if(r->sym != S && (r->sym->type & SMASK == 0 || r->sym->type & SMASK == SXREF)) {
diag("%s: not defined", r->sym->name);
continue;
}
if(r->type >= 256)
continue;
if(r->sym != S && r->sym->type == SDYNIMPORT)
diag("unhandled relocation for %s (type %d rtype %d)", r->sym->name, r->sym->type, r->type);
if(r->sym != S && !r->sym->reachable)
diag("unreachable sym in relocation: %s %s", s->name, r->sym->name);
switch(r->type) {
default:
o = 0;
if(isobj || archreloc(r, s, &o) < 0)
diag("unknown reloc %d", r->type);
break;
case D_ADDR:
o = symaddr(r->sym) + r->add;
if(isobj && r->sym->type != SCONST) {
if(thechar == '6')
o = 0;
else {
// set up addend for eventual relocation via outer symbol
rs = r->sym;
while(rs->outer != nil)
rs = rs->outer;
o -= symaddr(rs);
}
}
break;
case D_PCREL:
// r->sym can be null when CALL $(constant) is transformed from absolute PC to relative PC call.
o = 0;
if(r->sym)
o += symaddr(r->sym);
o += r->add - (s->value + r->off + r->siz);
if(isobj && r->sym->type != SCONST) {
if(thechar == '6')
o = 0;
else
o = r->add - r->siz;
}
break;
case D_SIZE:
o = r->sym->size + r->add;
break;
}
//print("relocate %s %p %s => %p %p %p %p [%p]\n", s->name, s->value+off, r->sym ? r->sym->name : "<nil>", (void*)symaddr(r->sym), (void*)s->value, (void*)r->off, (void*)r->siz, (void*)o);
switch(siz) {
default:
cursym = s;
diag("bad reloc size %#ux for %s", siz, r->sym->name);
case 4:
fl = o;
cast = (uchar*)&fl;
for(i=0; i<4; i++)
s->p[off+i] = cast[inuxi4[i]];
break;
case 8:
cast = (uchar*)&o;
for(i=0; i<8; i++)
s->p[off+i] = cast[inuxi8[i]];
break;
}
}
}
/*
* Apply a single intra-module relocation to the data. `relbase' is the
* target relocation base for the section (i.e. it corresponds to where
* r_offset == 0). `dataaddr' is the relocated address corresponding to
* the start of the data, and `len' is the number of bytes.
*/
int
__elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata,
int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len)
{
#ifdef __sparc__
Elf_Size w;
const Elf_Rela *a;
switch (reltype) {
case ELF_RELOC_RELA:
a = reldata;
if (relbase + a->r_offset >= dataaddr &&
relbase + a->r_offset < dataaddr + len) {
switch (ELF_R_TYPE(a->r_info)) {
case R_SPARC_RELATIVE:
w = relbase + a->r_addend;
bcopy(&w, (u_char *)data + (relbase +
a->r_offset - dataaddr), sizeof(w));
break;
default:
printf("\nunhandled relocation type %u\n",
(u_int)ELF_R_TYPE(a->r_info));
return (EFTYPE);
}
}
break;
}
return (0);
#elif (defined(__i386__) || defined(__amd64__)) && __ELF_WORD_SIZE == 64
Elf64_Addr *where, val;
Elf_Addr addend, addr;
Elf_Size rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
/* XXX, definitions not available on i386. */
#define R_X86_64_64 1
#define R_X86_64_RELATIVE 8
switch (rtype) {
case R_X86_64_64: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
case R_X86_64_RELATIVE:
addr = (Elf_Addr)addend + relbase;
val = addr;
*where = val;
break;
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__i386__) && __ELF_WORD_SIZE == 32
Elf_Addr addend, addr, *where, val;
Elf_Size rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
/* XXX, definitions not available on amd64. */
#define R_386_32 1 /* Add symbol value. */
#define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */
#define R_386_RELATIVE 8 /* Add load address of shared object. */
switch (rtype) {
case R_386_RELATIVE:
addr = addend + relbase;
*where = addr;
break;
case R_386_32: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__powerpc__)
Elf_Size w;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_RELA:
rela = reldata;
if (relbase + rela->r_offset >= dataaddr &&
relbase + rela->r_offset < dataaddr + len) {
switch (ELF_R_TYPE(rela->r_info)) {
case R_PPC_RELATIVE:
w = relbase + rela->r_addend;
bcopy(&w, (u_char *)data + (relbase +
rela->r_offset - dataaddr), sizeof(w));
break;
default:
printf("\nunhandled relocation type %u\n",
(u_int)ELF_R_TYPE(rela->r_info));
return (EFTYPE);
}
}
break;
}
return (0);
#else
(void)ef;
(void)symaddr;
(void)reldata;
(void)reltype;
(void)relbase;
(void)dataaddr;
(void)data;
(void)len;
return (EOPNOTSUPP);
#endif
}
void
relocsym(LSym *s)
{
Reloc *r;
LSym *rs;
int32 i, off, siz, fl;
vlong o;
uchar *cast;
ctxt->cursym = s;
for(r=s->r; r<s->r+s->nr; r++) {
r->done = 1;
off = r->off;
siz = r->siz;
if(off < 0 || off+siz > s->np) {
diag("%s: invalid relocation %d+%d not in [%d,%d)", s->name, off, siz, 0, s->np);
continue;
}
if(r->sym != S && ((r->sym->type & (SMASK | SHIDDEN)) == 0 || (r->sym->type & SMASK) == SXREF)) {
diag("%s: not defined", r->sym->name);
continue;
}
if(r->type >= 256)
continue;
if(r->siz == 0) // informational relocation - no work to do
continue;
// Solaris needs the ability to reference dynimport symbols.
if(HEADTYPE != Hsolaris && r->sym != S && r->sym->type == SDYNIMPORT)
diag("unhandled relocation for %s (type %d rtype %d)", r->sym->name, r->sym->type, r->type);
if(r->sym != S && r->sym->type != STLSBSS && !r->sym->reachable)
diag("unreachable sym in relocation: %s %s", s->name, r->sym->name);
// Android emulates runtime.tlsg as a regular variable.
if (r->type == R_TLS && strcmp(goos, "android") == 0)
r->type = R_ADDR;
switch(r->type) {
default:
o = 0;
if(archreloc(r, s, &o) < 0)
diag("unknown reloc %d", r->type);
break;
case R_TLS:
if(linkmode == LinkInternal && iself && thechar == '5') {
// On ELF ARM, the thread pointer is 8 bytes before
// the start of the thread-local data block, so add 8
// to the actual TLS offset (r->sym->value).
// This 8 seems to be a fundamental constant of
// ELF on ARM (or maybe Glibc on ARM); it is not
// related to the fact that our own TLS storage happens
// to take up 8 bytes.
o = 8 + r->sym->value;
break;
}
r->done = 0;
o = 0;
if(thechar != '6')
o = r->add;
break;
case R_TLS_LE:
if(linkmode == LinkExternal && iself && HEADTYPE != Hopenbsd) {
r->done = 0;
r->sym = ctxt->tlsg;
r->xsym = ctxt->tlsg;
r->xadd = r->add;
o = 0;
if(thechar != '6')
o = r->add;
break;
}
o = ctxt->tlsoffset + r->add;
break;
case R_TLS_IE:
if(linkmode == LinkExternal && iself && HEADTYPE != Hopenbsd) {
r->done = 0;
r->sym = ctxt->tlsg;
r->xsym = ctxt->tlsg;
r->xadd = r->add;
o = 0;
if(thechar != '6')
o = r->add;
break;
}
if(iself || ctxt->headtype == Hplan9)
o = ctxt->tlsoffset + r->add;
else if(ctxt->headtype == Hwindows)
o = r->add;
else
sysfatal("unexpected R_TLS_IE relocation for %s", headstr(ctxt->headtype));
break;
case R_ADDR:
if(linkmode == LinkExternal && r->sym->type != SCONST) {
r->done = 0;
// set up addend for eventual relocation via outer symbol.
rs = r->sym;
r->xadd = r->add;
while(rs->outer != nil) {
r->xadd += symaddr(rs) - symaddr(rs->outer);
rs = rs->outer;
}
if(rs->type != SHOSTOBJ && rs->type != SDYNIMPORT && rs->sect == nil)
diag("missing section for %s", rs->name);
r->xsym = rs;
o = r->xadd;
if(iself) {
if(thechar == '6')
o = 0;
} else if(HEADTYPE == Hdarwin) {
if(rs->type != SHOSTOBJ)
o += symaddr(rs);
} else {
diag("unhandled pcrel relocation for %s", headstring);
}
break;
}
o = symaddr(r->sym) + r->add;
// On amd64, 4-byte offsets will be sign-extended, so it is impossible to
// access more than 2GB of static data; fail at link time is better than
// fail at runtime. See http://golang.org/issue/7980.
// Instead of special casing only amd64, we treat this as an error on all
// 64-bit architectures so as to be future-proof.
if((int32)o < 0 && PtrSize > 4 && siz == 4) {
diag("non-pc-relative relocation address is too big: %#llux", o);
errorexit();
}
break;
case R_CALL:
case R_PCREL:
// r->sym can be null when CALL $(constant) is transformed from absolute PC to relative PC call.
if(linkmode == LinkExternal && r->sym && r->sym->type != SCONST && r->sym->sect != ctxt->cursym->sect) {
r->done = 0;
// set up addend for eventual relocation via outer symbol.
rs = r->sym;
r->xadd = r->add;
while(rs->outer != nil) {
r->xadd += symaddr(rs) - symaddr(rs->outer);
rs = rs->outer;
}
r->xadd -= r->siz; // relative to address after the relocated chunk
if(rs->type != SHOSTOBJ && rs->type != SDYNIMPORT && rs->sect == nil)
diag("missing section for %s", rs->name);
r->xsym = rs;
o = r->xadd;
if(iself) {
if(thechar == '6')
o = 0;
} else if(HEADTYPE == Hdarwin) {
if(r->type == R_CALL) {
if(rs->type != SHOSTOBJ)
o += symaddr(rs) - rs->sect->vaddr;
o -= r->off; // relative to section offset, not symbol
} else {
o += r->siz;
}
} else {
diag("unhandled pcrel relocation for %s", headstring);
}
break;
}
o = 0;
if(r->sym)
o += symaddr(r->sym);
// NOTE: The (int32) cast on the next line works around a bug in Plan 9's 8c
// compiler. The expression s->value + r->off + r->siz is int32 + int32 +
// uchar, and Plan 9 8c incorrectly treats the expression as type uint32
// instead of int32, causing incorrect values when sign extended for adding
// to o. The bug only occurs on Plan 9, because this C program is compiled by
// the standard host compiler (gcc on most other systems).
o += r->add - (s->value + r->off + (int32)r->siz);
break;
case R_SIZE:
o = r->sym->size + r->add;
break;
}
//print("relocate %s %#llux (%#llux+%#llux, size %d) => %s %#llux +%#llx [%llx]\n", s->name, (uvlong)(s->value+off), (uvlong)s->value, (uvlong)r->off, r->siz, r->sym ? r->sym->name : "<nil>", (uvlong)symaddr(r->sym), (vlong)r->add, (vlong)o);
switch(siz) {
default:
ctxt->cursym = s;
diag("bad reloc size %#ux for %s", siz, r->sym->name);
case 1:
// TODO(rsc): Remove.
s->p[off] = (int8)o;
break;
case 4:
if(r->type == R_PCREL || r->type == R_CALL) {
if(o != (int32)o)
diag("pc-relative relocation address is too big: %#llx", o);
} else {
if(o != (int32)o && o != (uint32)o)
diag("non-pc-relative relocation address is too big: %#llux", o);
}
fl = o;
cast = (uchar*)&fl;
for(i=0; i<4; i++)
s->p[off+i] = cast[inuxi4[i]];
break;
case 8:
cast = (uchar*)&o;
for(i=0; i<8; i++)
s->p[off+i] = cast[inuxi8[i]];
break;
}
}
}
// assign addresses
void
address(void)
{
Section *s, *text, *data, *rodata, *symtab, *pclntab, *noptr, *bss, *noptrbss;
Section *typelink;
LSym *sym, *sub;
uvlong va;
vlong vlen;
va = INITTEXT;
segtext.rwx = 05;
segtext.vaddr = va;
segtext.fileoff = HEADR;
for(s=segtext.sect; s != nil; s=s->next) {
va = rnd(va, s->align);
s->vaddr = va;
va += s->len;
}
segtext.len = va - INITTEXT;
segtext.filelen = segtext.len;
if(HEADTYPE == Hnacl)
va += 32; // room for the "halt sled"
if(segrodata.sect != nil) {
// align to page boundary so as not to mix
// rodata and executable text.
va = rnd(va, INITRND);
segrodata.rwx = 04;
segrodata.vaddr = va;
segrodata.fileoff = va - segtext.vaddr + segtext.fileoff;
segrodata.filelen = 0;
for(s=segrodata.sect; s != nil; s=s->next) {
va = rnd(va, s->align);
s->vaddr = va;
va += s->len;
}
segrodata.len = va - segrodata.vaddr;
segrodata.filelen = segrodata.len;
}
va = rnd(va, INITRND);
segdata.rwx = 06;
segdata.vaddr = va;
segdata.fileoff = va - segtext.vaddr + segtext.fileoff;
segdata.filelen = 0;
if(HEADTYPE == Hwindows)
segdata.fileoff = segtext.fileoff + rnd(segtext.len, PEFILEALIGN);
if(HEADTYPE == Hplan9)
segdata.fileoff = segtext.fileoff + segtext.filelen;
data = nil;
noptr = nil;
bss = nil;
noptrbss = nil;
for(s=segdata.sect; s != nil; s=s->next) {
vlen = s->len;
if(s->next)
vlen = s->next->vaddr - s->vaddr;
s->vaddr = va;
va += vlen;
segdata.len = va - segdata.vaddr;
if(strcmp(s->name, ".data") == 0)
data = s;
if(strcmp(s->name, ".noptrdata") == 0)
noptr = s;
if(strcmp(s->name, ".bss") == 0)
bss = s;
if(strcmp(s->name, ".noptrbss") == 0)
noptrbss = s;
}
segdata.filelen = bss->vaddr - segdata.vaddr;
text = segtext.sect;
if(segrodata.sect)
rodata = segrodata.sect;
else
rodata = text->next;
typelink = rodata->next;
symtab = typelink->next;
pclntab = symtab->next;
for(sym = datap; sym != nil; sym = sym->next) {
ctxt->cursym = sym;
if(sym->sect != nil)
sym->value += sym->sect->vaddr;
for(sub = sym->sub; sub != nil; sub = sub->sub)
sub->value += sym->value;
}
xdefine("runtime.text", STEXT, text->vaddr);
xdefine("runtime.etext", STEXT, text->vaddr + text->len);
xdefine("runtime.rodata", SRODATA, rodata->vaddr);
xdefine("runtime.erodata", SRODATA, rodata->vaddr + rodata->len);
xdefine("runtime.typelink", SRODATA, typelink->vaddr);
xdefine("runtime.etypelink", SRODATA, typelink->vaddr + typelink->len);
sym = linklookup(ctxt, "runtime.gcdata", 0);
xdefine("runtime.egcdata", SRODATA, symaddr(sym) + sym->size);
linklookup(ctxt, "runtime.egcdata", 0)->sect = sym->sect;
sym = linklookup(ctxt, "runtime.gcbss", 0);
xdefine("runtime.egcbss", SRODATA, symaddr(sym) + sym->size);
linklookup(ctxt, "runtime.egcbss", 0)->sect = sym->sect;
xdefine("runtime.symtab", SRODATA, symtab->vaddr);
xdefine("runtime.esymtab", SRODATA, symtab->vaddr + symtab->len);
xdefine("runtime.pclntab", SRODATA, pclntab->vaddr);
xdefine("runtime.epclntab", SRODATA, pclntab->vaddr + pclntab->len);
xdefine("runtime.noptrdata", SNOPTRDATA, noptr->vaddr);
xdefine("runtime.enoptrdata", SNOPTRDATA, noptr->vaddr + noptr->len);
xdefine("runtime.bss", SBSS, bss->vaddr);
xdefine("runtime.ebss", SBSS, bss->vaddr + bss->len);
xdefine("runtime.data", SDATA, data->vaddr);
xdefine("runtime.edata", SDATA, data->vaddr + data->len);
xdefine("runtime.noptrbss", SNOPTRBSS, noptrbss->vaddr);
xdefine("runtime.enoptrbss", SNOPTRBSS, noptrbss->vaddr + noptrbss->len);
xdefine("runtime.end", SBSS, segdata.vaddr + segdata.len);
}
