This makes the __tls_get_addr_opt test run as a shared library, and so
actually test that DTPMOD64/DTPREL64 pairs are processed by ld.so to
support the __tls_get_adfr_opt call stub fast return. After a
2017-01-24 patch (binutils f0158f4416) ld.bfd no longer emitted
unnecessary dynamic relocations against local thread variables,
instead setting up the __tls_index GOT entries for the call stub fast
return. This meant tst-tlsopt-powerpc passed but did not check ld.so
relocation support. After a 2017-07-16 patch (binutils 676ee2b5fa)
ld.bfd no longer set up the __tls_index GOT entries for the call stub
fast return, and tst-tlsopt-powerpc failed.
Compiling mod-tlsopt-powerpc.c with -DSHARED exposed a bug in
powerpc64/tls-macros.h, which defines a __TLS_GET_ADDR macro that
clashes with one defined in dl-tls.h. The tls-macros.h version is
only used in that file, so delete it and expand.
* sysdeps/powerpc/mod-tlsopt-powerpc.c: Extract from
tst-tlsopt-powerpc.c with function name change and no test harness.
* sysdeps/powerpc/tst-tlsopt-powerpc.c: Remove body of test.
Call tls_get_addr_opt_test.
* sysdeps/powerpc/Makefile (LDFLAGS-tst-tlsopt-powerpc): Don't define.
(modules-names): Add mod-tlsopt-powerpc.
(mod-tlsopt-powerpc.so-no-z-defs): Define.
(tst-tlsopt-powerpc): Depend on .so.
* sysdeps/powerpc/powerpc64/tls-macros.h (__TLS_GET_ADDR): Don't
define. Expand use in TLS_GD and TLS_LD.
Change the powerpc tests to use <support/test-driver.c>.
Also replace some of pthread calls to its xpthread equivalent.
Tested on ppc64le.
* sysdeps/powerpc/test-get_hwcap.c: Use <support/test-driver.c>
instead of test-skeleton.c.
(do_test): Replaced pthread_create and pthread_join with
xpthread_create and xpthread_join. Use TEST_VERIFY_EXIT macro.
Removed unneeded status variable.
* sysdeps/powerpc/test-gettimebase.c: Use <support/test-driver.c>
instead of test-skeleton.c.
* sysdeps/powerpc/tst-tlsopt-powerpc.c: Likewise.
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.
Alan Modra
Wainer dos Santos Moschetta