glibc/sysdeps/ia64/dl-machine.h

582 lines
15 KiB
C

/* Machine-dependent ELF dynamic relocation inline functions. IA-64 version.
Copyright (C) 1995, 1996, 1997, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#ifndef dl_machine_h
#define dl_machine_h 1
#define ELF_MACHINE_NAME "ia64"
#include <assert.h>
#include <string.h>
#include <link.h>
#include <errno.h>
/* Translate a processor specific dynamic tag to the index
in l_info array. */
#define DT_IA_64(x) (DT_IA_64_##x - DT_LOPROC + DT_NUM)
/* An FPTR is a function descriptor. Properly they consist of just
FUNC and GP. But we want to traverse a binary tree too. */
#define IA64_BOOT_FPTR_SIZE 256
struct ia64_fptr
{
Elf64_Addr func;
Elf64_Addr gp;
struct ia64_fptr *next;
};
extern struct ia64_fptr __boot_ldso_fptr[];
extern struct ia64_fptr *__fptr_next;
extern struct ia64_fptr *__fptr_root;
extern int __fptr_count;
extern Elf64_Addr __ia64_make_fptr (const struct link_map *, Elf64_Addr,
struct ia64_fptr **, struct ia64_fptr *);
/* Return nonzero iff E_MACHINE is compatible with the running host. */
static inline int
elf_machine_matches_host (Elf64_Word e_machine)
{
return e_machine == EM_IA_64;
}
/* Return the link-time address of _DYNAMIC. */
static inline Elf64_Addr
elf_machine_dynamic (void)
{
Elf64_Addr *p;
__asm__(
".section .sdata\n"
" .type __dynamic_ltv#, @object\n"
" .size __dynamic_ltv#, 8\n"
"__dynamic_ltv:\n"
" data8 @ltv(_DYNAMIC#)\n"
".previous\n"
" addl %0 = @gprel(__dynamic_ltv#), gp ;;"
: "=r"(p));
return *p;
}
/* Return the run-time load address of the shared object. */
static inline Elf64_Addr
elf_machine_load_address (void)
{
Elf64_Addr ip;
int *p;
__asm__(
"1: mov %0 = ip\n"
".section .sdata\n"
"2: data4 @ltv(1b)\n"
" .align 8\n"
".previous\n"
" addl %1 = @gprel(2b), gp ;;"
: "=r"(ip), "=r"(p));
return ip - (Elf64_Addr)*p;
}
/* Set up the loaded object described by L so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */
static inline int
elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
{
extern void _dl_runtime_resolve (void);
extern void _dl_runtime_profile (void);
if (lazy)
{
register Elf64_Addr gp __asm__("gp");
Elf64_Addr *reserve, doit;
/*
* Careful with the typecast here or it will try to add l-l_addr
* pointer elements
*/
reserve = (Elf64_Addr *)
(l->l_info[DT_IA_64(PLT_RESERVE)]->d_un.d_ptr + l->l_addr);
/* Identify this shared object. */
reserve[0] = (Elf64_Addr) l;
/* This function will be called to perform the relocation. */
if (!profile)
doit = (Elf64_Addr) ((struct ia64_fptr *)&_dl_runtime_resolve)->func;
else
{
if (_dl_name_match_p (_dl_profile, l))
{
/* This is the object we are looking for. Say that we really
want profiling and the timers are started. */
_dl_profile_map = l;
}
doit = (Elf64_Addr) ((struct ia64_fptr *)&_dl_runtime_profile)->func;
}
reserve[1] = doit;
reserve[2] = gp;
}
return lazy;
}
/*
This code is used in dl-runtime.c to call the `fixup' function
and then redirect to the address it returns. `fixup()' takes two
arguments, however fixup_profile() takes three.
The ABI specifies that we will never see more than 8 input
registers to a function call, thus it is safe to simply allocate
those, and simpler than playing stack games.
- 12/09/99 Jes
*/
#define TRAMPOLINE_TEMPLATE(tramp_name, fixup_name) \
extern void tramp_name (void); \
asm ( "\
.global " #tramp_name "#
.proc " #tramp_name "#
" #tramp_name ":
{ .mmi
alloc loc0 = ar.pfs, 8, 2, 3, 0
adds r2 = -144, r12
adds r3 = -128, r12
}
{ .mii
adds r12 = -160, r12
mov loc1 = b0
mov out2 = b0 /* needed by fixup_profile */
;;
}
{ .mmi
stf.spill [r2] = f8, 32
stf.spill [r3] = f9, 32
mov out0 = r16
;;
}
{ .mmi
stf.spill [r2] = f10, 32
stf.spill [r3] = f11, 32
shl out1 = r15, 4
;;
}
{ .mmi
stf.spill [r2] = f12, 32
stf.spill [r3] = f13, 32
shladd out1 = r15, 3, out1
;;
}
{ .mmb
stf.spill [r2] = f14
stf.spill [r3] = f15
br.call.sptk.many b0 = " #fixup_name "#
}
{ .mii
ld8 r9 = [ret0], 8
adds r2 = 16, r12
adds r3 = 32, r12
;;
}
{ .mmi
ldf.fill f8 = [r2], 32
ldf.fill f9 = [r3], 32
mov b0 = loc1
;;
}
{ .mmi
ldf.fill f10 = [r2], 32
ldf.fill f11 = [r3], 32
mov b6 = r9
;;
}
{ .mmi
ldf.fill f12 = [r2], 32
ldf.fill f13 = [r3], 32
mov ar.pfs = loc0
;;
}
{ .mmi
ldf.fill f14 = [r2], 32
ldf.fill f15 = [r3], 32
adds r12 = 160, r12
;;
}
/* An alloc is needed for the break system call to work.
We don't care about the old value of the pfs register. */
{ .mmb
alloc r2 = ar.pfs, 0, 0, 8, 0
ld8 gp = [ret0]
br.sptk.many b6
;;
}
.endp " #tramp_name "#")
#ifndef PROF
#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup); \
TRAMPOLINE_TEMPLATE (_dl_runtime_profile, profile_fixup);
#else
#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup); \
strong_alias (_dl_runtime_resolve, _dl_runtime_profile);
#endif
/* Initial entry point code for the dynamic linker.
The C function `_dl_start' is the real entry point;
its return value is the user program's entry point. */
#define RTLD_START asm ("\
.text
.global _start#
.proc _start#
_start:
0: { .mii
alloc loc0 = ar.pfs, 0, 3, 4, 0
mov r2 = ip
addl r3 = @gprel(0b), r0
;;
}
{ .mlx
/* Calculate the GP, and save a copy in loc1. */
sub gp = r2, r3
movl r8 = 0x9804c0270033f
;;
}
{ .mii
mov ar.fpsr = r8
sub loc1 = r2, r3
/* _dl_start wants a pointer to the pointer to the arg block
and the arg block starts with an integer, thus the magic 16. */
adds out0 = 16, sp
}
{ .bbb
br.call.sptk.many b0 = _dl_start#
;;
}
.endp _start#
/* FALLTHRU */
.global _dl_start_user#
.proc _dl_start_user#
_dl_start_user:
{ .mii
/* Save the pointer to the user entry point fptr in loc2. */
mov loc2 = ret0
/* Store the highest stack address. */
addl r2 = @ltoff(__libc_stack_end#), gp
addl r3 = @gprel(_dl_skip_args), gp
;;
}
{ .mmi
ld8 r2 = [r2]
ld4 r3 = [r3]
adds r11 = 24, sp /* Load the address of argv. */
;;
}
{ .mii
st8 [r2] = sp
adds r10 = 16, sp /* Load the address of argc. */
mov out2 = r11
;;
/* See if we were run as a command with the executable file
name as an extra leading argument. If so, adjust the argv
pointer to skip _dl_skip_args words.
Note that _dl_skip_args is an integer, not a long - Jes
The stack pointer has to be 16 byte aligned. We cannot simply
addjust the stack pointer. We have to move the whole argv and
envp. H.J. */
}
{ .mmi
ld8 out1 = [r10] /* is argc actually stored as a long
or as an int? */
;;
sub out1 = out1, r3 /* Get the new argc. */
shladd r15 = r3, 3, r11 /* The address of the argv we move */
;;
}
/* ??? Could probably merge these two loops into 3 bundles.
using predication to control which set of copies we're on. */
1: /* Copy argv. */
{ .mfi
ld8 r16 = [r15], 8 /* Load the value in the old argv. */
;;
}
{ .mib
st8 [r11] = r16, 8 /* Store it in the new argv. */
cmp.ne p6, p7 = 0, r16
(p6) br.cond.dptk.few 1b
;;
}
{ .mib
mov out3 = r11
addl out0 = @ltoff(_dl_loaded), gp
}
1: /* Copy env. */
{ .mfi
ld8 r16 = [r15], 8 /* Load the value in the old env. */
;;
}
{ .mib
st8 [r11] = r16, 8 /* Store it in the new env. */
cmp.ne p6, p7 = 0, r16
(p6) br.cond.dptk.few 1b
;;
}
{ .mmb
st8 [r10] = out1 /* Record the new argc. */
ld8 out0 = [out0]
}
{ .mfb
ld8 out0 = [out0] /* get the linkmap */
br.call.sptk.many b0 = _dl_init#
;;
}
/* Pass our finializer function to the user,
and jump to the user's entry point. */
{ .mmi
ld8 r3 = [loc2], 8
mov b0 = r0
}
{ .mmi
addl ret0 = @ltoff(@fptr(_dl_fini#)), gp
;;
mov b6 = r3
}
{ .mmi
ld8 ret0 = [ret0]
ld8 gp = [loc2]
mov ar.pfs = loc0
;;
}
{ .mfb
br.sptk.many b6
;;
}
.endp _dl_start_user#
.previous");
#ifndef RTLD_START_SPECIAL_INIT
#define RTLD_START_SPECIAL_INIT /* nothing */
#endif
/* Nonzero iff TYPE describes relocation of a PLT entry, so
PLT entries should not be allowed to define the value. */
/* ??? Ignore IPLTMSB for now. */
#define elf_machine_lookup_noplt_p(type) ((type) == R_IA64_IPLTLSB)
/* Nonzero iff TYPE should not be allowed to resolve to one of
the main executable's symbols, as for a COPY reloc, which we don't use. */
#define elf_machine_lookup_noexec_p(type) (0)
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_IA64_IPLTLSB
/* According to the IA-64 specific documentation, Rela is always used. */
#define ELF_MACHINE_NO_REL 1
/* Since ia64's stack has to be 16byte aligned, we cannot arbitrarily
move the stack pointer. */
#define ELF_MACHINE_FIXED_STACK 1
/* Return the address of the entry point. */
extern ElfW(Addr) _dl_start_address (const struct link_map *map,
ElfW(Addr) start);
#define ELF_MACHINE_START_ADDRESS(map, start) \
_dl_start_address ((map), (start))
#define elf_machine_profile_fixup_plt(l, reloc, rel_addr, value) \
elf_machine_fixup_plt ((l), (reloc), (rel_addr), (value))
#define elf_machine_profile_plt(reloc_addr) ((Elf64_Addr) (reloc_addr))
/* Fixup a PLT entry to bounce directly to the function at VALUE. */
static inline Elf64_Addr
elf_machine_fixup_plt (struct link_map *l, lookup_t t,
const Elf64_Rela *reloc,
Elf64_Addr *reloc_addr, Elf64_Addr value)
{
/* l is the link_map for the caller, t is the link_map for the object
* being called */
/* got has already been relocated in elf_get_dynamic_info() */
reloc_addr[1] = t->l_info[DT_PLTGOT]->d_un.d_ptr;
reloc_addr[0] = value;
return (Elf64_Addr) reloc_addr;
}
/* Return the final value of a plt relocation. */
static inline Elf64_Addr
elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
Elf64_Addr value)
{
/* No need to handle rel vs rela since IA64 is rela only */
return value + reloc->r_addend;
}
#endif /* !dl_machine_h */
#ifdef RESOLVE_MAP
#define R_IA64_TYPE(R) ((R) & -8)
#define R_IA64_FORMAT(R) ((R) & 7)
#define R_IA64_FORMAT_32MSB 4
#define R_IA64_FORMAT_32LSB 5
#define R_IA64_FORMAT_64MSB 6
#define R_IA64_FORMAT_64LSB 7
/* Perform the relocation specified by RELOC and SYM (which is fully
resolved). MAP is the object containing the reloc. */
static inline void
elf_machine_rela (struct link_map *map,
const Elf64_Rela *reloc,
const Elf64_Sym *sym,
const struct r_found_version *version,
Elf64_Addr *const reloc_addr)
{
unsigned long const r_type = ELF64_R_TYPE (reloc->r_info);
Elf64_Addr value;
#ifndef RTLD_BOOTSTRAP
/* This is defined in rtld.c, but nowhere in the static libc.a; make the
reference weak so static programs can still link. This declaration
cannot be done when compiling rtld.c (i.e. #ifdef RTLD_BOOTSTRAP)
because rtld.c contains the common defn for _dl_rtld_map, which is
incompatible with a weak decl in the same file. */
weak_extern (_dl_rtld_map);
#endif
/* We cannot use a switch here because we cannot locate the switch
jump table until we've self-relocated. */
if (R_IA64_TYPE (r_type) == R_IA64_TYPE (R_IA64_REL64LSB))
{
value = *reloc_addr;
#ifndef RTLD_BOOTSTRAP
/* Already done in dynamic linker. */
if (map != &_dl_rtld_map)
#endif
value += map->l_addr;
}
else if (r_type == R_IA64_NONE)
return;
else
{
struct link_map *sym_map;
/*
* RESOLVE_MAP() will return NULL if it fail to locate the symbol
*/
if ((sym_map = RESOLVE_MAP (&sym, version, r_type)))
{
value = sym ? sym_map->l_addr + sym->st_value : 0;
value += reloc->r_addend;
if (R_IA64_TYPE (r_type) == R_IA64_TYPE (R_IA64_DIR64LSB))
;/* No adjustment. */
else if (r_type == R_IA64_IPLTLSB)
{
elf_machine_fixup_plt (NULL, sym_map, reloc, reloc_addr, value);
return;
}
else if (R_IA64_TYPE (r_type) == R_IA64_TYPE (R_IA64_FPTR64LSB))
#ifndef RTLD_BOOTSTRAP
value = __ia64_make_fptr (sym_map, value, &__fptr_root, NULL);
#else
{
struct ia64_fptr *p_boot_ldso_fptr;
struct ia64_fptr **p_fptr_root;
int *p_fptr_count;
/* Special care must be taken to address these variables
during bootstrap. Further, since we don't know exactly
when __fptr_next will be relocated, we index directly
off __boot_ldso_fptr. */
asm ("addl %0 = @gprel(__boot_ldso_fptr#), gp\n\t"
"addl %1 = @gprel(__fptr_root#), gp\n\t"
"addl %2 = @gprel(__fptr_count#), gp"
: "=r"(p_boot_ldso_fptr),
"=r"(p_fptr_root),
"=r"(p_fptr_count));
/*
* Go from the top - __ia64_make_fptr goes from the bottom,
* this way we will never clash.
*/
value = __ia64_make_fptr (sym_map, value, p_fptr_root,
&p_boot_ldso_fptr[--*p_fptr_count]);
}
#endif
else if (R_IA64_TYPE (r_type) == R_IA64_TYPE (R_IA64_PCREL64LSB))
value -= (Elf64_Addr)reloc_addr & -16;
else
assert (! "unexpected dynamic reloc type");
}
else
value = 0;
}
/* ??? Ignore MSB and Instruction format for now. */
if (R_IA64_FORMAT (r_type) == R_IA64_FORMAT_64LSB)
*reloc_addr = value;
else if (R_IA64_FORMAT (r_type) == R_IA64_FORMAT_32LSB)
*(int *)reloc_addr = value;
else if (r_type == R_IA64_IPLTLSB)
{
reloc_addr[0] = 0;
reloc_addr[1] = 0;
}
else
assert (! "unexpected dynamic reloc format");
}
/* Perform a RELATIVE reloc on the .got entry that transfers to the .plt. */
static inline void
elf_machine_lazy_rel (struct link_map *map,
Elf64_Addr l_addr, const Elf64_Rela *reloc)
{
Elf64_Addr * const reloc_addr = (void *)(l_addr + reloc->r_offset);
unsigned long const r_type = ELF64_R_TYPE (reloc->r_info);
if (r_type == R_IA64_IPLTLSB)
{
reloc_addr[0] += l_addr;
reloc_addr[1] += l_addr;
}
else if (r_type == R_IA64_NONE)
return;
else
assert (! "unexpected PLT reloc type");
}
#endif /* RESOLVE_MAP */