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This patch is glibc support for a PowerPC TLS optimization, inspired by Alexandre Oliva's TLS optimization for other processors, http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt In essence, this optimization uses a zero module id in the tls_index GOT entry to indicate that a TLS variable is allocated space in the static TLS area. A special plt call linker stub for __tls_get_addr checks for such a tls_index and if found, returns the offset immediately. The linker communicates the fact that the special __tls_get_addr stub is used by setting a bit in the dynamic tag DT_PPC64_OPT/DT_PPC_OPT. glibc communicates to the linker that this optimization is available by the presence of __tls_get_addr_opt. tst-tlsmod2.so is built with -Wl,--no-tls-get-addr-optimize for tst-tls-dlinfo, which otherwise would fail since it tests that no static tls is allocated. The ld option --no-tls-get-addr-optimize has been available since binutils-2.20 so doesn't need a configure test. * NEWS: Advertise TLS optimization. * elf/elf.h (R_PPC_TLSGD, R_PPC_TLSLD, DT_PPC_OPT, PPC_OPT_TLS): Define. (DT_PPC_NUM): Increment. * elf/dynamic-link.h (HAVE_STATIC_TLS): Define. (CHECK_STATIC_TLS): Use here. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Optimize TLS descriptors. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/dl-tls.c: New file. * sysdeps/powerpc/Versions: Add __tls_get_addr_opt. * sysdeps/powerpc/tst-tlsopt-powerpc.c: New tls test. * sysdeps/unix/sysv/linux/powerpc/Makefile: Add new test. Build tst-tlsmod2.so with --no-tls-get-addr-optimize. * sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist: Update. * sysdeps/unix/sysv/linux/powerpc/powerpc64/ld.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/ld-le.abilist: Likewise. |
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.. | ||
bits | ||
fpu | ||
nofpu | ||
nptl | ||
power4 | ||
power5+/fpu | ||
power6 | ||
power7/fpu | ||
powerpc32 | ||
powerpc64 | ||
soft-fp | ||
sys/platform | ||
abort-instr.h | ||
dl-procinfo.c | ||
dl-procinfo.h | ||
dl-tls.c | ||
dl-tls.h | ||
ffs.c | ||
fpu_control.h | ||
gccframe.h | ||
ifunc-sel.h | ||
Implies | ||
jmpbuf-offsets.h | ||
jmpbuf-unwind.h | ||
ldsodefs.h | ||
locale-defines.sym | ||
longjmp.c | ||
machine-gmon.h | ||
Makefile | ||
math-tests.h | ||
memusage.h | ||
mp_clz_tab.c | ||
novmx-longjmp.c | ||
novmx-sigjmp.c | ||
novmxsetjmp.h | ||
preconfigure | ||
rtld-global-offsets.sym | ||
sched_cpucount.c | ||
sigjmp.c | ||
sotruss-lib.c | ||
stackinfo.h | ||
strcat.c | ||
sysdep.h | ||
test-arith.c | ||
test-arithf.c | ||
test-gettimebase.c | ||
tls-macros.h | ||
tst-stack-align.h | ||
tst-tlsopt-powerpc.c | ||
Versions |