glibc/sysdeps/arm/dl-machine.h

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/* Machine-dependent ELF dynamic relocation inline functions. ARM version.
Copyright (C) 1995-2021 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
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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
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library. If not, see
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
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<https://www.gnu.org/licenses/>. */
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#ifndef dl_machine_h
#define dl_machine_h
#define ELF_MACHINE_NAME "ARM"
elf: Fix elf_get_dynamic_info definition Before to 490e6c62aa31a8a ('elf: Avoid nested functions in the loader [BZ #27220]'), elf_get_dynamic_info() was defined twice on rtld.c: on the first dynamic-link.h include and later within _dl_start(). The former definition did not define DONT_USE_BOOTSTRAP_MAP and it is used on setup_vdso() (since it is a global definition), while the former does define DONT_USE_BOOTSTRAP_MAP and it is used on loader self-relocation. With the commit change, the function is now included and defined once instead of defined as a nested function. So rtld.c defines without defining RTLD_BOOTSTRAP and it brokes at least powerpc32. This patch fixes by moving the get-dynamic-info.h include out of dynamic-link.h, which then the caller can corirectly set the expected semantic by defining STATIC_PIE_BOOTSTRAP, RTLD_BOOTSTRAP, and/or RESOLVE_MAP. It also required to enable some asserts only for the loader bootstrap to avoid issues when called from setup_vdso(). As a side note, this is another issues with nested functions: it is not clear from pre-processed output (-E -dD) how the function will be build and its semantic (since nested function will be local and extra C defines may change it). I checked on x86_64-linux-gnu (w/o --enable-static-pie), i686-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu-power4, aarch64-linux-gnu, arm-linux-gnu, sparc64-linux-gnu, and s390x-linux-gnu. Reviewed-by: Fangrui Song <maskray@google.com> (cherry picked from commit 4af6982e4c9fc465ffb7a54b794aaaa134241f05) Resolved conflicts: elf/rtld.c
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#include <assert.h>
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#include <sys/param.h>
#include <tls.h>
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#include <dl-tlsdesc.h>
#include <dl-irel.h>
elf: Fix dynamic-link.h usage on rtld.c The 4af6982e4c fix does not fully handle RTLD_BOOTSTRAP usage on rtld.c due two issues: 1. RTLD_BOOTSTRAP is also used on dl-machine.h on various architectures and it changes the semantics of various machine relocation functions. 2. The elf_get_dynamic_info() change was done sideways, previously to 490e6c62aa get-dynamic-info.h was included by the first dynamic-link.h include *without* RTLD_BOOTSTRAP being defined. It means that the code within elf_get_dynamic_info() that uses RTLD_BOOTSTRAP is in fact unused. To fix 1. this patch now includes dynamic-link.h only once with RTLD_BOOTSTRAP defined. The ELF_DYNAMIC_RELOCATE call will now have the relocation fnctions with the expected semantics for the loader. And to fix 2. part of 4af6982e4c is reverted (the check argument elf_get_dynamic_info() is not required) and the RTLD_BOOTSTRAP pieces are removed. To reorganize the includes the static TLS definition is moved to its own header to avoid a circular dependency (it is defined on dynamic-link.h and dl-machine.h requires it at same time other dynamic-link.h definition requires dl-machine.h defitions). Also ELF_MACHINE_NO_REL, ELF_MACHINE_NO_RELA, and ELF_MACHINE_PLT_REL are moved to its own header. Only ancient ABIs need special values (arm, i386, and mips), so a generic one is used as default. The powerpc Elf64_FuncDesc is also moved to its own header, since csu code required its definition (which would require either include elf/ folder or add a full path with elf/). Checked on x86_64, i686, aarch64, armhf, powerpc64, powerpc32, and powerpc64le. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com> (cherry picked from commit d6d89608ac8cf2b37c75debad1fff653f6939f90) Resolved conflicts: elf/rtld.c
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#include <dl-static-tls.h>
#include <dl-machine-rel.h>
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#ifndef CLEAR_CACHE
# error CLEAR_CACHE definition required to handle TEXTREL
#endif
/* Return nonzero iff ELF header is compatible with the running host. */
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static inline int __attribute__ ((unused))
elf_machine_matches_host (const Elf32_Ehdr *ehdr)
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{
return ehdr->e_machine == EM_ARM;
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}
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
first element of the GOT. */
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static inline Elf32_Addr __attribute__ ((unused))
elf_machine_dynamic (void)
{
/* Declaring this hidden ensures that a PC-relative reference is used. */
extern const Elf32_Addr _GLOBAL_OFFSET_TABLE_[] attribute_hidden;
return _GLOBAL_OFFSET_TABLE_[0];
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}
/* Return the run-time load address of the shared object. */
static inline Elf32_Addr __attribute__ ((unused))
elf_machine_load_address (void)
{
Elf32_Addr pcrel_addr;
#ifdef SHARED
extern Elf32_Addr __dl_start (void *) asm ("_dl_start");
Elf32_Addr got_addr = (Elf32_Addr) &__dl_start;
asm ("adr %0, _dl_start" : "=r" (pcrel_addr));
#else
extern Elf32_Addr __dl_relocate_static_pie (void *)
asm ("_dl_relocate_static_pie") attribute_hidden;
Elf32_Addr got_addr = (Elf32_Addr) &__dl_relocate_static_pie;
asm ("adr %0, _dl_relocate_static_pie" : "=r" (pcrel_addr));
#endif
#ifdef __thumb__
/* Clear the low bit of the function address.
NOTE: got_addr is from GOT table whose lsb is always set by linker if it's
Thumb function address. PCREL_ADDR comes from PC-relative calculation
which will finish during assembling. GAS assembler before the fix for
PR gas/21458 was not setting the lsb but does after that. Always do the
strip for both, so the code works with various combinations of glibc and
Binutils. */
got_addr &= ~(Elf32_Addr) 1;
pcrel_addr &= ~(Elf32_Addr) 1;
#endif
return pcrel_addr - got_addr;
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}
/* 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 __attribute__ ((unused))
elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
int lazy, int profile)
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{
Elf32_Addr *got;
extern void _dl_runtime_resolve (Elf32_Word);
extern void _dl_runtime_profile (Elf32_Word);
if (l->l_info[DT_JMPREL] && lazy)
{
/* patb: this is different than i386 */
/* The GOT entries for functions in the PLT have not yet been filled
in. Their initial contents will arrange when called to push an
index into the .got section, load ip with &_GLOBAL_OFFSET_TABLE_[3],
and then jump to _GLOBAL_OFFSET_TABLE[2]. */
got = (Elf32_Addr *) D_PTR (l, l_info[DT_PLTGOT]);
/* If a library is prelinked but we have to relocate anyway,
we have to be able to undo the prelinking of .got.plt.
The prelinker saved us here address of .plt. */
if (got[1])
l->l_mach.plt = got[1] + l->l_addr;
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got[1] = (Elf32_Addr) l; /* Identify this shared object. */
/* The got[2] entry contains the address of a function which gets
called to get the address of a so far unresolved function and
jump to it. The profiling extension of the dynamic linker allows
to intercept the calls to collect information. In this case we
don't store the address in the GOT so that all future calls also
end in this function. */
if (profile)
{
got[2] = (Elf32_Addr) &_dl_runtime_profile;
if (GLRO(dl_profile) != NULL
&& _dl_name_match_p (GLRO(dl_profile), l))
/* Say that we really want profiling and the timers are
started. */
GL(dl_profile_map) = l;
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}
else
/* This function will get called to fix up the GOT entry indicated by
the offset on the stack, and then jump to the resolved address. */
got[2] = (Elf32_Addr) &_dl_runtime_resolve;
}
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return lazy;
}
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#if defined(ARCH_HAS_BX)
#define BX(x) "bx\t" #x
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#else
#define BX(x) "mov\tpc, " #x
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#endif
/* Mask identifying addresses reserved for the user program,
where the dynamic linker should not map anything. */
#define ELF_MACHINE_USER_ADDRESS_MASK 0xf8000000UL
/* 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\n\
.globl _start\n\
.type _start, %function\n\
.globl _dl_start_user\n\
.type _dl_start_user, %function\n\
_start:\n\
@ we are PIC code, so get global offset table\n\
ldr sl, .L_GET_GOT\n\
@ See if we were run as a command with the executable file\n\
@ name as an extra leading argument.\n\
ldr r4, .L_SKIP_ARGS\n\
@ at start time, all the args are on the stack\n\
mov r0, sp\n\
bl _dl_start\n\
@ returns user entry point in r0\n\
_dl_start_user:\n\
adr r6, .L_GET_GOT\n\
add sl, sl, r6\n\
ldr r4, [sl, r4]\n\
@ save the entry point in another register\n\
mov r6, r0\n\
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@ get the original arg count\n\
ldr r1, [sp]\n\
@ get the argv address\n\
add r2, sp, #4\n\
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@ Fix up the stack if necessary.\n\
cmp r4, #0\n\
bne .L_fixup_stack\n\
.L_done_fixup:\n\
@ compute envp\n\
add r3, r2, r1, lsl #2\n\
add r3, r3, #4\n\
@ now we call _dl_init\n\
ldr r0, .L_LOADED\n\
ldr r0, [sl, r0]\n\
@ call _dl_init\n\
Don't use INTDEF/INTUSE with _dl_init (bug 14132). Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this patch eliminates its use for _dl_init. Since _dl_init was already declared with hidden visibility, creating a second hidden alias for it was completely pointless, so this patch replaces all uses of _dl_init_internal with plain _dl_init instead of using hidden_proto / hidden_def (which are only needed when you want a hidden alias for a non-hidden symbol; it's quite possible there are cases where they are used but don't need to be because the symbol in question is not part of the public ABI and is only used within a single library, so using attributes_hidden instead would suffice). Tested for x86_64 that installed stripped shared libraries are unchanged by the patch. [BZ #14132] * elf/dl-init.c (_dl_init): Don't use INTDEF. * sysdeps/aarch64/dl-machine.h (RTLD_START): Use _dl_init instead of _dl_init_internal. * sysdeps/alpha/dl-machine.h (RTLD_START): Likewise. * sysdeps/arm/dl-machine.h (RTLD_START): Likewise. * sysdeps/hppa/dl-machine.h (RTLD_START): Likewise. * sysdeps/i386/dl-machine.h (RTLD_START): Likewise. * sysdeps/ia64/dl-machine.h (RTLD_START): Likewise. * sysdeps/m68k/dl-machine.h (RTLD_START): Likewise. * sysdeps/microblaze/dl-machine.h (RTLD_START): Likewise. * sysdeps/mips/dl-machine.h (RTLD_START): Likewise. * sysdeps/powerpc/powerpc32/dl-start.S (_start): Likewise. * sysdeps/s390/s390-32/dl-machine.h (RTLD_START): Likewise. * sysdeps/s390/s390-64/dl-machine.h (RTLD_START): Likewise. * sysdeps/sh/dl-machine.h (RTLD_START): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (RTLD_START): Likewise. * sysdeps/tile/dl-start.S (_start): Likewise. * sysdeps/x86_64/dl-machine.h (RTLD_START): Likewise. * sysdeps/x86_64/x32/dl-machine.h (RTLD_START): Likewise.
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bl _dl_init(PLT)\n\
@ load the finalizer function\n\
ldr r0, .L_FINI_PROC\n\
add r0, sl, r0\n\
@ jump to the user_s entry point\n\
" BX(r6) "\n\
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\n\
@ iWMMXt and EABI targets require the stack to be eight byte\n\
@ aligned - shuffle arguments etc.\n\
.L_fixup_stack:\n\
@ subtract _dl_skip_args from original arg count\n\
sub r1, r1, r4\n\
@ store the new argc in the new stack location\n\
str r1, [sp]\n\
@ find the first unskipped argument\n\
mov r3, r2\n\
add r4, r2, r4, lsl #2\n\
@ shuffle argv down\n\
1: ldr r5, [r4], #4\n\
str r5, [r3], #4\n\
cmp r5, #0\n\
bne 1b\n\
@ shuffle envp down\n\
1: ldr r5, [r4], #4\n\
str r5, [r3], #4\n\
cmp r5, #0\n\
bne 1b\n\
@ shuffle auxv down\n\
1: ldmia r4!, {r0, r5}\n\
stmia r3!, {r0, r5}\n\
cmp r0, #0\n\
bne 1b\n\
@ Update _dl_argv\n\
ldr r3, .L_ARGV\n\
str r2, [sl, r3]\n\
b .L_done_fixup\n\
\n\
.L_GET_GOT:\n\
.word _GLOBAL_OFFSET_TABLE_ - .L_GET_GOT\n\
.L_SKIP_ARGS:\n\
.word _dl_skip_args(GOTOFF)\n\
.L_FINI_PROC:\n\
.word _dl_fini(GOTOFF)\n\
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.L_ARGV:\n\
.word _dl_argv(GOTOFF)\n\
.L_LOADED:\n\
.word _rtld_local(GOTOFF)\n\
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.previous\n\
");
/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
TLS variable, so undefined references should not be allowed to
define the value.
ELF_RTYPE_CLASS_COPY iff TYPE should not be allowed to resolve to one
of the main executable's symbols, as for a COPY reloc.
ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA iff TYPE describes relocation against
protected data whose address may be external due to copy relocation. */
#ifndef RTLD_BOOTSTRAP
# define elf_machine_type_class(type) \
((((type) == R_ARM_JUMP_SLOT || (type) == R_ARM_TLS_DTPMOD32 \
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|| (type) == R_ARM_TLS_DTPOFF32 || (type) == R_ARM_TLS_TPOFF32 \
|| (type) == R_ARM_TLS_DESC) \
* ELF_RTYPE_CLASS_PLT) \
| (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY) \
| (((type) == R_ARM_GLOB_DAT) * ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA))
#else
#define elf_machine_type_class(type) \
((((type) == R_ARM_JUMP_SLOT) * ELF_RTYPE_CLASS_PLT) \
| (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY) \
| (((type) == R_ARM_GLOB_DAT) * ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA))
#endif
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/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
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#define ELF_MACHINE_JMP_SLOT R_ARM_JUMP_SLOT
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/* We define an initialization functions. This is called very early in
_dl_sysdep_start. */
#define DL_PLATFORM_INIT dl_platform_init ()
static inline void __attribute__ ((unused))
dl_platform_init (void)
{
if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0')
/* Avoid an empty string which would disturb us. */
GLRO(dl_platform) = NULL;
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}
static inline Elf32_Addr
elf_machine_fixup_plt (struct link_map *map, lookup_t t,
PowerPC64 ELFv2 PPC64_OPT_LOCALENTRY ELFv2 functions with localentry:0 are those with a single entry point, ie. global entry == local entry, that have no requirement on r2 or r12 and guarantee r2 is unchanged on return. Such an external function can be called via the PLT without saving r2 or restoring it on return, avoiding a common load-hit-store for small functions. This patch implements the ld.so changes necessary for this optimization. ld.so needs to check that an optimized plt call sequence is in fact calling a function implemented with localentry:0, end emit a fatal error otherwise. The elf/testobj6.c change is to stop "error while loading shared libraries: expected localentry:0 `preload'" when running elf/preloadtest, which we'd get otherwise. * elf/elf.h (PPC64_OPT_LOCALENTRY): Define. * sysdeps/alpha/dl-machine.h (elf_machine_fixup_plt): Add refsym and sym parameters. Adjust callers. * sysdeps/aarch64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/generic/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/mips/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.c (_dl_error_localentry): New. (_dl_reloc_overflow): Increase buffser size. Formatting. * sysdeps/powerpc/powerpc64/dl-machine.h (ppc64_local_entry_offset): Delete reloc param, add refsym and sym. Check optimized plt call stubs for localentry:0 functions. Adjust callers. (elf_machine_fixup_plt, elf_machine_plt_conflict): Add refsym and sym parameters. Adjust callers. (_dl_reloc_overflow): Move attribute. (_dl_error_localentry): Declare. * elf/dl-runtime.c (_dl_fixup): Save original sym. Pass refsym and sym to elf_machine_fixup_plt. * elf/testobj6.c (preload): Call printf.
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const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const Elf32_Rel *reloc,
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Elf32_Addr *reloc_addr, Elf32_Addr value)
{
return *reloc_addr = value;
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}
/* Return the final value of a plt relocation. */
static inline Elf32_Addr
elf_machine_plt_value (struct link_map *map, const Elf32_Rel *reloc,
Elf32_Addr value)
{
return value;
}
#endif /* !dl_machine_h */
/* Names of the architecture-specific auditing callback functions. */
#define ARCH_LA_PLTENTER arm_gnu_pltenter
#define ARCH_LA_PLTEXIT arm_gnu_pltexit
#ifdef RESOLVE_MAP
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/* Handle a PC24 reloc, including the out-of-range case. */
static void
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relocate_pc24 (struct link_map *map, Elf32_Addr value,
Elf32_Addr *const reloc_addr, Elf32_Sword addend)
{
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Elf32_Addr new_value;
/* Set NEW_VALUE based on V, and return true iff it overflows 24 bits. */
inline bool set_new_value (Elf32_Addr v)
{
new_value = v + addend - (Elf32_Addr) reloc_addr;
Elf32_Addr topbits = new_value & 0xfe000000;
return topbits != 0xfe000000 && topbits != 0x00000000;
}
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if (set_new_value (value))
{
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/* The PC-relative address doesn't fit in 24 bits! */
static void *fix_page;
static size_t fix_offset;
if (fix_page == NULL)
{
void *new_page = __mmap (NULL, GLRO(dl_pagesize),
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANON, -1, 0);
if (new_page == MAP_FAILED)
_dl_signal_error (0, map->l_name, NULL,
"could not map page for fixup");
fix_page = new_page;
assert (fix_offset == 0);
}
Elf32_Word *fix_address = fix_page + fix_offset;
fix_address[0] = 0xe51ff004; /* ldr pc, [pc, #-4] */
fix_address[1] = value;
fix_offset += sizeof fix_address[0] * 2;
if (fix_offset >= GLRO(dl_pagesize))
{
fix_page = NULL;
fix_offset = 0;
}
if (set_new_value ((Elf32_Addr) fix_address))
_dl_signal_error (0, map->l_name, NULL,
"R_ARM_PC24 relocation out of range");
}
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*reloc_addr = (*reloc_addr & 0xff000000) | ((new_value >> 2) & 0x00ffffff);
}
1998-03-18 14:28:36 +00:00
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
MAP is the object containing the reloc. */
static inline void
__attribute__ ((always_inline))
elf_machine_rel (struct link_map *map, struct r_scope_elem *scope[],
const Elf32_Rel *reloc, const Elf32_Sym *sym,
const struct r_found_version *version,
void *const reloc_addr_arg, int skip_ifunc)
1998-03-18 14:28:36 +00:00
{
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
Elf32_Addr *const reloc_addr = reloc_addr_arg;
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
#if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC
if (__builtin_expect (r_type == R_ARM_RELATIVE, 0))
1998-03-18 14:28:36 +00:00
{
# if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC
/* 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. */
# ifndef SHARED
weak_extern (_dl_rtld_map);
# endif
if (map != &GL(dl_rtld_map)) /* Already done in rtld itself. */
# endif
1998-03-18 14:28:36 +00:00
*reloc_addr += map->l_addr;
}
# ifndef RTLD_BOOTSTRAP
else if (__builtin_expect (r_type == R_ARM_NONE, 0))
return;
# endif
else
#endif
1998-03-18 14:28:36 +00:00
{
const Elf32_Sym *const refsym = sym;
struct link_map *sym_map = RESOLVE_MAP (map, scope, &sym, version,
r_type);
elf: Unify symbol address run-time calculation [BZ #19818] Wrap symbol address run-time calculation into a macro and use it throughout, replacing inline calculations. There are a couple of variants, most of them different in a functionally insignificant way. Most calculations are right following RESOLVE_MAP, at which point either the map or the symbol returned can be checked for validity as the macro sets either both or neither. In some places both the symbol and the map has to be checked however. My initial implementation therefore always checked both, however that resulted in code larger by as much as 0.3%, as many places know from elsewhere that no check is needed. I have decided the size growth was unacceptable. Having looked closer I realized that it's the map that is the culprit. Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional boolean argument telling it to access the map without checking it for validity. This in turn has brought quite nice results, with new code actually being smaller for i686, and MIPS o32, n32 and little-endian n64 targets, unchanged in size for x86-64 and, unusually, marginally larger for big-endian MIPS n64, as follows: i686: text data bss dec hex filename 152255 4052 192 156499 26353 ld-2.27.9000-base.so 152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so MIPS/o32/el: text data bss dec hex filename 142906 4396 260 147562 2406a ld-2.27.9000-base.so 142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so MIPS/n32/el: text data bss dec hex filename 142267 4404 260 146931 23df3 ld-2.27.9000-base.so 142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so MIPS/n64/el: text data bss dec hex filename 149835 7376 408 157619 267b3 ld-2.27.9000-base.so 149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so MIPS/o32/eb: text data bss dec hex filename 142870 4396 260 147526 24046 ld-2.27.9000-base.so 142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so MIPS/n32/eb: text data bss dec hex filename 142019 4404 260 146683 23cfb ld-2.27.9000-base.so 141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so MIPS/n64/eb: text data bss dec hex filename 149763 7376 408 157547 2676b ld-2.27.9000-base.so 149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so x86-64: text data bss dec hex filename 148462 6452 400 155314 25eb2 ld-2.27.9000-base.so 148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so [BZ #19818] * sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set' parameter. (SYMBOL_ADDRESS): New macro. [!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use SYMBOL_ADDRESS for symbol address calculation. * elf/dl-runtime.c (_dl_fixup): Likewise. (_dl_profile_fixup): Likewise. * elf/dl-symaddr.c (_dl_symbol_address): Likewise. * elf/rtld.c (dl_main): Likewise. * sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC): Likewise. (elf_machine_reloc): Likewise. (elf_machine_got_rel): Likewise. * sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2018-04-04 22:09:37 +00:00
Elf32_Addr value = SYMBOL_ADDRESS (sym_map, sym, true);
1998-03-18 14:28:36 +00:00
if (sym != NULL
&& __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0)
&& __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
&& __builtin_expect (!skip_ifunc, 1))
value = elf_ifunc_invoke (value);
switch (r_type)
1998-03-18 14:28:36 +00:00
{
case R_ARM_COPY:
if (sym == NULL)
/* This can happen in trace mode if an object could not be
found. */
break;
if (sym->st_size > refsym->st_size
|| (GLRO(dl_verbose) && sym->st_size < refsym->st_size))
1998-03-18 14:28:36 +00:00
{
const char *strtab;
strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
_dl_error_printf ("\
%s: Symbol `%s' has different size in shared object, consider re-linking\n",
RTLD_PROGNAME, strtab + refsym->st_name);
1998-03-18 14:28:36 +00:00
}
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
memcpy (reloc_addr_arg, (void *) value,
MIN (sym->st_size, refsym->st_size));
1998-03-18 14:28:36 +00:00
break;
case R_ARM_GLOB_DAT:
1998-06-09 15:13:18 +00:00
case R_ARM_JUMP_SLOT:
# ifdef RTLD_BOOTSTRAP
/* Fix weak undefined references. */
if (sym != NULL && sym->st_value == 0)
*reloc_addr = 0;
else
# endif
*reloc_addr = value;
1998-03-18 14:28:36 +00:00
break;
1998-06-09 15:13:18 +00:00
case R_ARM_ABS32:
1998-03-18 14:28:36 +00:00
{
struct unaligned
{
Elf32_Addr x;
} __attribute__ ((packed, may_alias));
# ifndef RTLD_BOOTSTRAP
1998-03-18 14:28:36 +00:00
/* 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. */
# ifndef SHARED
1998-03-18 14:28:36 +00:00
weak_extern (_dl_rtld_map);
# endif
if (map == &GL(dl_rtld_map))
1998-03-18 14:28:36 +00:00
/* Undo the relocation done here during bootstrapping.
Now we will relocate it anew, possibly using a
binding found in the user program or a loaded library
rather than the dynamic linker's built-in definitions
used while loading those libraries. */
elf: Unify symbol address run-time calculation [BZ #19818] Wrap symbol address run-time calculation into a macro and use it throughout, replacing inline calculations. There are a couple of variants, most of them different in a functionally insignificant way. Most calculations are right following RESOLVE_MAP, at which point either the map or the symbol returned can be checked for validity as the macro sets either both or neither. In some places both the symbol and the map has to be checked however. My initial implementation therefore always checked both, however that resulted in code larger by as much as 0.3%, as many places know from elsewhere that no check is needed. I have decided the size growth was unacceptable. Having looked closer I realized that it's the map that is the culprit. Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional boolean argument telling it to access the map without checking it for validity. This in turn has brought quite nice results, with new code actually being smaller for i686, and MIPS o32, n32 and little-endian n64 targets, unchanged in size for x86-64 and, unusually, marginally larger for big-endian MIPS n64, as follows: i686: text data bss dec hex filename 152255 4052 192 156499 26353 ld-2.27.9000-base.so 152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so MIPS/o32/el: text data bss dec hex filename 142906 4396 260 147562 2406a ld-2.27.9000-base.so 142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so MIPS/n32/el: text data bss dec hex filename 142267 4404 260 146931 23df3 ld-2.27.9000-base.so 142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so MIPS/n64/el: text data bss dec hex filename 149835 7376 408 157619 267b3 ld-2.27.9000-base.so 149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so MIPS/o32/eb: text data bss dec hex filename 142870 4396 260 147526 24046 ld-2.27.9000-base.so 142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so MIPS/n32/eb: text data bss dec hex filename 142019 4404 260 146683 23cfb ld-2.27.9000-base.so 141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so MIPS/n64/eb: text data bss dec hex filename 149763 7376 408 157547 2676b ld-2.27.9000-base.so 149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so x86-64: text data bss dec hex filename 148462 6452 400 155314 25eb2 ld-2.27.9000-base.so 148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so [BZ #19818] * sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set' parameter. (SYMBOL_ADDRESS): New macro. [!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use SYMBOL_ADDRESS for symbol address calculation. * elf/dl-runtime.c (_dl_fixup): Likewise. (_dl_profile_fixup): Likewise. * elf/dl-symaddr.c (_dl_symbol_address): Likewise. * elf/rtld.c (dl_main): Likewise. * sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC): Likewise. (elf_machine_reloc): Likewise. (elf_machine_got_rel): Likewise. * sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2018-04-04 22:09:37 +00:00
value -= SYMBOL_ADDRESS (map, refsym, true);
# endif
/* Support relocations on mis-aligned offsets. */
((struct unaligned *) reloc_addr)->x += value;
1998-03-18 14:28:36 +00:00
break;
}
2011-03-05 03:39:15 +00:00
case R_ARM_TLS_DESC:
{
struct tlsdesc *td = (struct tlsdesc *)reloc_addr;
2011-03-05 03:39:15 +00:00
# ifndef RTLD_BOOTSTRAP
if (! sym)
td->entry = _dl_tlsdesc_undefweak;
else
# endif
{
if (ELF32_R_SYM (reloc->r_info) == STN_UNDEF)
value = td->argument.value;
else
value = sym->st_value;
2011-03-05 03:39:15 +00:00
# ifndef RTLD_BOOTSTRAP
# ifndef SHARED
CHECK_STATIC_TLS (map, sym_map);
# else
if (!TRY_STATIC_TLS (map, sym_map))
{
td->argument.pointer
= _dl_make_tlsdesc_dynamic (sym_map, value);
td->entry = _dl_tlsdesc_dynamic;
}
else
# endif
# endif
{
2011-03-05 03:39:15 +00:00
td->argument.value = value + sym_map->l_tls_offset;
td->entry = _dl_tlsdesc_return;
}
2011-03-05 03:39:15 +00:00
}
}
break;
case R_ARM_PC24:
2012-10-05 16:39:23 +00:00
relocate_pc24 (map, value, reloc_addr,
/* Sign-extend the 24-bit addend in the
instruction (which counts instructions), and
then shift it up two so as to count bytes. */
(((Elf32_Sword) *reloc_addr << 8) >> 8) << 2);
break;
#if !defined RTLD_BOOTSTRAP
case R_ARM_TLS_DTPMOD32:
/* Get the information from the link map returned by the
resolv function. */
if (sym_map != NULL)
*reloc_addr = sym_map->l_tls_modid;
break;
case R_ARM_TLS_DTPOFF32:
if (sym != NULL)
*reloc_addr += sym->st_value;
break;
case R_ARM_TLS_TPOFF32:
if (sym != NULL)
{
CHECK_STATIC_TLS (map, sym_map);
*reloc_addr += sym->st_value + sym_map->l_tls_offset;
}
break;
case R_ARM_IRELATIVE:
value = map->l_addr + *reloc_addr;
if (__glibc_likely (!skip_ifunc))
value = ((Elf32_Addr (*) (int)) value) (GLRO(dl_hwcap));
*reloc_addr = value;
break;
#endif
1998-03-18 14:28:36 +00:00
default:
_dl_reloc_bad_type (map, r_type, 0);
1998-03-18 14:28:36 +00:00
break;
}
}
}
# ifndef RTLD_BOOTSTRAP
static inline void
__attribute__ ((always_inline))
elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
const Elf32_Rela *reloc, const Elf32_Sym *sym,
const struct r_found_version *version,
void *const reloc_addr_arg, int skip_ifunc)
{
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
Elf32_Addr *const reloc_addr = reloc_addr_arg;
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
if (__builtin_expect (r_type == R_ARM_RELATIVE, 0))
*reloc_addr = map->l_addr + reloc->r_addend;
else if (__builtin_expect (r_type == R_ARM_NONE, 0))
return;
else
{
# ifndef RESOLVE_CONFLICT_FIND_MAP
const Elf32_Sym *const refsym = sym;
# endif
struct link_map *sym_map = RESOLVE_MAP (map, scope, &sym, version, r_type);
elf: Unify symbol address run-time calculation [BZ #19818] Wrap symbol address run-time calculation into a macro and use it throughout, replacing inline calculations. There are a couple of variants, most of them different in a functionally insignificant way. Most calculations are right following RESOLVE_MAP, at which point either the map or the symbol returned can be checked for validity as the macro sets either both or neither. In some places both the symbol and the map has to be checked however. My initial implementation therefore always checked both, however that resulted in code larger by as much as 0.3%, as many places know from elsewhere that no check is needed. I have decided the size growth was unacceptable. Having looked closer I realized that it's the map that is the culprit. Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional boolean argument telling it to access the map without checking it for validity. This in turn has brought quite nice results, with new code actually being smaller for i686, and MIPS o32, n32 and little-endian n64 targets, unchanged in size for x86-64 and, unusually, marginally larger for big-endian MIPS n64, as follows: i686: text data bss dec hex filename 152255 4052 192 156499 26353 ld-2.27.9000-base.so 152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so MIPS/o32/el: text data bss dec hex filename 142906 4396 260 147562 2406a ld-2.27.9000-base.so 142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so MIPS/n32/el: text data bss dec hex filename 142267 4404 260 146931 23df3 ld-2.27.9000-base.so 142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so MIPS/n64/el: text data bss dec hex filename 149835 7376 408 157619 267b3 ld-2.27.9000-base.so 149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so MIPS/o32/eb: text data bss dec hex filename 142870 4396 260 147526 24046 ld-2.27.9000-base.so 142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so MIPS/n32/eb: text data bss dec hex filename 142019 4404 260 146683 23cfb ld-2.27.9000-base.so 141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so MIPS/n64/eb: text data bss dec hex filename 149763 7376 408 157547 2676b ld-2.27.9000-base.so 149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so x86-64: text data bss dec hex filename 148462 6452 400 155314 25eb2 ld-2.27.9000-base.so 148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so [BZ #19818] * sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set' parameter. (SYMBOL_ADDRESS): New macro. [!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use SYMBOL_ADDRESS for symbol address calculation. * elf/dl-runtime.c (_dl_fixup): Likewise. (_dl_profile_fixup): Likewise. * elf/dl-symaddr.c (_dl_symbol_address): Likewise. * elf/rtld.c (dl_main): Likewise. * sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC): Likewise. (elf_machine_reloc): Likewise. (elf_machine_got_rel): Likewise. * sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2018-04-04 22:09:37 +00:00
Elf32_Addr value = SYMBOL_ADDRESS (sym_map, sym, true);
if (sym != NULL
&& __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0)
&& __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
&& __builtin_expect (!skip_ifunc, 1))
value = elf_ifunc_invoke (value);
switch (r_type)
{
# ifndef RESOLVE_CONFLICT_FIND_MAP
/* Not needed for dl-conflict.c. */
case R_ARM_COPY:
if (sym == NULL)
/* This can happen in trace mode if an object could not be
found. */
break;
if (sym->st_size > refsym->st_size
|| (GLRO(dl_verbose) && sym->st_size < refsym->st_size))
{
const char *strtab;
strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
_dl_error_printf ("\
%s: Symbol `%s' has different size in shared object, consider re-linking\n",
RTLD_PROGNAME, strtab + refsym->st_name);
}
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
memcpy (reloc_addr_arg, (void *) value,
MIN (sym->st_size, refsym->st_size));
break;
# endif /* !RESOLVE_CONFLICT_FIND_MAP */
case R_ARM_GLOB_DAT:
case R_ARM_JUMP_SLOT:
case R_ARM_ABS32:
*reloc_addr = value + reloc->r_addend;
break;
case R_ARM_PC24:
2012-10-05 16:39:23 +00:00
relocate_pc24 (map, value, reloc_addr, reloc->r_addend);
break;
#if !defined RTLD_BOOTSTRAP
case R_ARM_TLS_DTPMOD32:
/* Get the information from the link map returned by the
resolv function. */
if (sym_map != NULL)
*reloc_addr = sym_map->l_tls_modid;
break;
case R_ARM_TLS_DTPOFF32:
*reloc_addr = (sym == NULL ? 0 : sym->st_value) + reloc->r_addend;
break;
case R_ARM_TLS_TPOFF32:
if (sym != NULL)
{
CHECK_STATIC_TLS (map, sym_map);
*reloc_addr = (sym->st_value + sym_map->l_tls_offset
+ reloc->r_addend);
}
break;
case R_ARM_IRELATIVE:
value = map->l_addr + reloc->r_addend;
if (__glibc_likely (!skip_ifunc))
value = ((Elf32_Addr (*) (int)) value) (GLRO(dl_hwcap));
*reloc_addr = value;
break;
#endif
default:
_dl_reloc_bad_type (map, r_type, 0);
break;
}
}
}
# endif
static inline void
__attribute__ ((always_inline))
elf_machine_rel_relative (Elf32_Addr l_addr, const Elf32_Rel *reloc,
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
void *const reloc_addr_arg)
{
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
Elf32_Addr *const reloc_addr = reloc_addr_arg;
*reloc_addr += l_addr;
}
# ifndef RTLD_BOOTSTRAP
static inline void
__attribute__ ((always_inline))
elf_machine_rela_relative (Elf32_Addr l_addr, const Elf32_Rela *reloc,
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
void *const reloc_addr_arg)
{
* elf/dynamic-link.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Don't assume reloc_addr is aligned. * sysdeps/alpha/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/arm/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/cris/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/hppa/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/i386/dl-machine.h (elf_machine_rel, elf_machine_rela, elf_machine_rel_relative, elf_machine_rela_relative): Adjust. * sysdeps/ia64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/m68k/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/mips/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela_relative, elf_machine_rela): Adjust. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): * sysdeps/sh/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust. * sysdeps/x86_64/dl-machine.h (elf_machine_rela, elf_machine_rela_relative): Adjust.
2003-07-31 06:33:52 +00:00
Elf32_Addr *const reloc_addr = reloc_addr_arg;
*reloc_addr = l_addr + reloc->r_addend;
}
# endif
static inline void
__attribute__ ((always_inline))
elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
Elf32_Addr l_addr, const Elf32_Rel *reloc,
int skip_ifunc)
1998-03-18 14:28:36 +00:00
{
Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
/* Check for unexpected PLT reloc type. */
if (__builtin_expect (r_type == R_ARM_JUMP_SLOT, 1))
{
if (__builtin_expect (map->l_mach.plt, 0) == 0)
*reloc_addr += l_addr;
else
*reloc_addr = map->l_mach.plt;
}
2011-03-05 03:39:15 +00:00
else if (__builtin_expect (r_type == R_ARM_TLS_DESC, 1))
{
const Elf_Symndx symndx = ELFW (R_SYM) (reloc->r_info);
const ElfW (Sym) *symtab = (const void *)D_PTR (map, l_info[DT_SYMTAB]);
const ElfW (Sym) *sym = &symtab[symndx];
const struct r_found_version *version = NULL;
if (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
{
const ElfW (Half) *vernum =
(const void *)D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
version = &map->l_versions[vernum[symndx] & 0x7fff];
}
/* Always initialize TLS descriptors completely, because lazy
initialization requires synchronization at every TLS access. */
elf_machine_rel (map, scope, reloc, sym, version, reloc_addr, skip_ifunc);
2011-03-05 03:39:15 +00:00
}
else
_dl_reloc_bad_type (map, r_type, 1);
1998-03-18 14:28:36 +00:00
}
#endif /* RESOLVE_MAP */