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Maciej W. Rozycki 10a446ddcc 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 23:09:37 +01:00
argp Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
assert Fix uninitialized variable in assert_perror (bug 22761) 2018-02-05 11:06:15 +01:00
benchtests Undefine attribute_hidden to fix benchtests 2018-03-19 10:53:14 +00:00
bits Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947] 2018-04-03 12:19:29 -07:00
catgets intl/tst-gettext: fix failure with newest msgfmt 2018-02-18 18:16:05 +01:00
ChangeLog.old Add missing reference to bug 21654 2017-10-07 13:14:36 +02:00
conform Don't install libio.h or _G_config.h. 2018-02-07 10:07:31 -05:00
crypt crypt: Fix badsalttest test (Bug 22765) 2018-02-01 00:02:49 -08:00
csu hurd: Initialize TLS and libpthread before signal thread start 2018-03-25 00:52:39 +01:00
ctype Use libc_hidden_* for tolower, toupper (bug 15105). 2018-02-23 13:54:53 +00:00
debug Use x86_64 backtrace as generic version. 2018-03-21 17:25:30 +00:00
dirent Define _DIRENT_MATCHES_DIRENT64 regardless 2018-03-05 18:10:04 -03:00
dlfcn Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
elf elf: Unify symbol address run-time calculation [BZ #19818] 2018-04-04 23:09:37 +01:00
gmon Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
gnulib Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
grp Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
gshadow Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
htl hurd: Avoid local PLT in libpthread 2018-04-03 02:56:35 +02:00
hurd hurd: Silence warning 2018-04-04 02:06:16 +02:00
iconv Fix s390 -Os iconv build. 2018-03-05 21:46:55 +00:00
iconvdata Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
include Revert parts of "hurd: Avoid more libc.so local PLTs" 2018-04-03 23:06:00 +02:00
inet inet: Actually build and run tst-deadline 2018-04-04 16:08:18 +02:00
intl intl/tst-gettext: fix failure with newest msgfmt 2018-02-18 18:16:05 +01:00
io Revert __dirfd PLT avoidance for now 2018-04-02 21:45:38 +02:00
libidn Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
libio hurd: Avoid more libc.so local PLTs 2018-04-03 00:36:33 +00:00
locale Fix two more -Os strcoll / wcscoll build failures. 2018-02-27 16:55:42 +00:00
localedata cs_CZ locale: Add alternative month names (bug 22963). 2018-03-15 01:21:02 +01:00
login Update copyright dates not handled by scripts/update-copyrights. 2018-01-01 00:41:16 +00:00
mach hurd: Add missing symbols 2018-04-04 02:17:49 +02:00
malloc malloc: harden removal from unsorted list 2018-03-14 16:25:57 -04:00
manual Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947] 2018-04-03 12:19:29 -07:00
math Add narrowing subtract functions. 2018-03-20 00:34:52 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
misc Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947] 2018-04-03 12:19:29 -07:00
nis libnsl: Turn remaining symbols into compat symbols [BZ #22701] 2018-01-29 17:42:30 +01:00
nptl Filter out NPTL internal signals (BZ #22391) 2018-04-03 13:30:49 -03:00
nptl_db nptl_db: Remove stale match_pid' parameter from iterate_thread_list' 2018-03-01 16:10:05 +00:00
nscd hurd: Add hurd thread library 2018-04-02 01:44:14 +02:00
nss Fix multiple definitions of __nss_*_database (bug 22918) 2018-03-03 17:44:24 +01:00
po Update translations from the Translation Project 2018-03-12 13:24:46 +00:00
posix Fix multiple definitions of __nss_*_database (bug 22918) 2018-03-03 17:44:24 +01:00
pwd Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
resolv hurd: Add hurd thread library 2018-04-02 01:44:14 +02:00
resource resource/tst-getrlimit.c: Add copyright header 2018-01-05 20:34:10 +01:00
rt hurd: Add hurd thread library 2018-04-02 01:44:14 +02:00
scripts Use Linux 4.16 in build-many-glibcs.py. 2018-04-03 15:41:08 +00:00
setjmp Revert parts of "hurd: Avoid more libc.so local PLTs" 2018-04-03 23:06:00 +02:00
shadow Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
signal hurd: fix build 2018-04-04 02:28:20 +02:00
socket Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
soft-fp Do not use packed structures in soft-fp. 2018-02-01 20:44:49 +00:00
stdio-common Remove miscellaneous debris from libio. 2018-02-21 14:39:54 -05:00
stdlib hurd: Avoid some PLTs in libc and librt 2018-04-02 19:07:52 +00:00
streams Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
string Fix i386 memmove issue (bug 22644). 2018-03-23 16:19:45 +01:00
sunrpc Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
support support_format_addrinfo: Include unknown error number in result 2018-04-01 19:41:01 +02:00
sysdeps elf: Unify symbol address run-time calculation [BZ #19818] 2018-04-04 23:09:37 +01:00
sysvipc Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
termios Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
time Fix -Os getc_unlocked linknamespace, localplt issues (bug 15105, bug 19463). 2018-02-21 18:01:11 +00:00
timezone Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
wcsmbs [BZ 1190] Make EOF sticky in stdio. 2018-03-13 08:31:56 -04:00
wctype Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 LIBC_SLIBDIR_RTLDDIR: substitute arguments in single quotes 2018-01-25 17:20:28 +01:00
ChangeLog elf: Unify symbol address run-time calculation [BZ #19818] 2018-04-04 23:09:37 +01:00
config.h.in Add RISC-V entries to config.h.in 2018-01-29 10:24:57 -08:00
config.make.in Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
configure Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
configure.ac Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Improve gen-locales.mk and gen-locale.sh to make test files with @ options work 2018-02-27 17:01:57 +01:00
INSTALL Document use of CC and CFLAGS in more detail (bug 20980, bug 21234). 2018-02-15 23:48:47 +00:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Add support for sqrt asm redirects 2018-03-15 19:21:35 +00:00
Makefile Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Define GEN_AS_CONST_HEADERS when generating header files [BZ #22792] 2018-02-23 11:29:39 -08:00
NEWS hurd: Announce that glibc now builds unpatched 2018-04-02 16:45:44 +02:00
o-iterator.mk Fri Mar 17 12:58:37 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu> 1995-03-17 18:42:51 +00:00
README hurd: Announce that glibc now builds unpatched 2018-04-02 16:45:44 +02:00
Rules Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
shlib-versions Extend NSS test suite 2017-07-17 15:52:44 -04:00
test-skeleton.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
version.h Open master branch for glibc 2.28 development 2018-02-01 17:18:19 +00:00

This directory contains the sources of the GNU C Library.
See the file "version.h" for what release version you have.

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