9e390558ce
This is in preparation for the next patch adding Spectre variant 2 mitigation for PowerPC and PowerPC64. Besides tidying code involved in stub output (to reduce the number of places where bctr is output), the patch adds some user visible features: 1) PowerPC64 ELFv2 global entry stubs now are aligned under the control of --plt-align, with a default alignment of 32 bytes. 2) PowerPC64 __glink_PLTresolve is no longer padded out with nops. 3) PowerPC32 PLT stubs are aligned under the control of --plt-align, with the default alignment being 16 bytes as before. 4) The PowerPC32 branch/nop table emitted before __glink_PLTresolve is now smaller in many cases. It was sized incorrectly when the __tls_get_addr_opt stub was used, and unnecessarily included space for local ifuncs. bfd/ * elf32-ppc.c (GLINK_ENTRY_SIZE): Add parameters, handle __tls_get_addr_opt, and alignment sizing. (TLS_GET_ADDR_GLINK_SIZE): Delete. (is_nonpic_glink_stub): Don't use GLINK_ENTRY_SIZE. (ppc_elf_get_synthetic_symtab): Recognize stubs spaced at 4, 6, or 8 insns. (ppc_elf_link_hash_table_create): Init new ppc_elf_params field. (allocate_dynrelocs): Use new GLINK_ENTRY_SIZE. (ppc_elf_size_dynamic_sections): Likewise. Size branch table by PLT reloc count. (write_glink_stub): Handle __tls_get_addr_opt stub. Pad out to size given by GLINK_ENTRY_SIZE. (ppc_elf_relocate_section): Adjust write_glink_stub call. (ppc_elf_finish_dynamic_symbol): Likewise. (ppc_elf_finish_dynamic_sections): Write PLTresolve without using insn array since so many need rewriting. * elf32-ppc.h (struct ppc_elf_params): Add plt_stub_align. * elf64-ppc.c (GLINK_PLTRESOLVE_SIZE): Rename from GLINK_CALL_STUB_SIZE. Add htab param and evaluate to size without nops. Adjust all uses. (ppc64_elf_get_synthetic_symtab): Don't use GLINK_CALL_STUB_SIZE in glink_vma calculation. (struct ppc_link_hash_table): Add global_entry section pointer. (create_linkage_sections): Create separate section for global entry stubs. (PPC_LO, PPC_HI, PPC_HA): Move earlier. (size_global_entry_stubs): Handle sizing for aligned stubs. (ppc64_elf_size_dynamic_sections): Handle global_entry alloc, and don't stash end of glink branch table in rawsize. (ppc_build_one_stub): Rewrite stub size calculations. (build_global_entry_stubs): Use new section. (ppc64_elf_build_stubs): Don't pad __glink_PLTresolve with nops. Build lazy link stubs out to end of section. Build global entry stubs in new section. gold/ * options.h (plt_align): Support for PowerPC32 too. * powerpc.cc (Stub_table::stub_align): Heed --plt-align for 32-bit. (Stub_table::plt_call_size, branch_stub_size): Tidy. (Stub_table::plt_call_align): Implement using stub_align. (Output_data_glink::global_entry_align): New function. (Output_data_glink::global_entry_off): New function. (Output_data_glink::global_entry_address): Use global_entry_off. (Output_data_glink::pltresolve_size): New function, replacing pltresolve_size_ constant. Update all uses. (Output_data_glink::add_global_entry): Align offset. (Output_data_glink::set_final_data_size): Use global_entry_align. (Stub_table::do_write): Don't pad __glink_PLTrelsolve with nops. Tidy stub output. Use global_entry_off. ld/ * emultempl/ppc32elf.em (params): Init new field. (enum ppc32_opt): New enum to define OPTION_* values. Add OPTION_PLT_ALIGN and OPTION_NO_PLT_ALIGN. (PARSE_AND_LIST_LONGOPTS): Handle new options. (PARSE_AND_LIST_ARGS_CASES): Likewise. (PARSE_AND_LIST_OPTIONS): Likewise. Break up help output. * emultempl/ppc64elf.em (ppc_add_stub_section): Init alignment correctly for negative --plt-stub-align. * testsuite/ld-powerpc/elfv2exe.d, * testsuite/ld-powerpc/elfv2so.d, * testsuite/ld-powerpc/relbrlt.d, * testsuite/ld-powerpc/relbrlt.s, * testsuite/ld-powerpc/tlsexe.d, * testsuite/ld-powerpc/tlsexe.r, * testsuite/ld-powerpc/tlsexe32.d, * testsuite/ld-powerpc/tlsexe32.g, * testsuite/ld-powerpc/tlsexe32.r, * testsuite/ld-powerpc/tlsexetoc.d, * testsuite/ld-powerpc/tlsexetoc.r, * testsuite/ld-powerpc/tlsopt5_32.d, * testsuite/ld-powerpc/tlsso.d, * testsuite/ld-powerpc/tlstocso.d: Update for changed stub order. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
readline | ||
sim | ||
texinfo | ||
zlib | ||
.cvsignore | ||
.gitattributes | ||
.gitignore | ||
COPYING | ||
COPYING.LIB | ||
COPYING.LIBGLOSS | ||
COPYING.NEWLIB | ||
COPYING3 | ||
COPYING3.LIB | ||
ChangeLog | ||
MAINTAINERS | ||
Makefile.def | ||
Makefile.in | ||
Makefile.tpl | ||
README | ||
README-maintainer-mode | ||
compile | ||
config-ml.in | ||
config.guess | ||
config.rpath | ||
config.sub | ||
configure | ||
configure.ac | ||
depcomp | ||
djunpack.bat | ||
install-sh | ||
libtool.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
lt~obsolete.m4 | ||
makefile.vms | ||
missing | ||
mkdep | ||
mkinstalldirs | ||
move-if-change | ||
setup.com | ||
src-release.sh | ||
symlink-tree | ||
ylwrap |
README
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.