binutils-gdb/ld
Clément Chigot 1b2cb8e2ee aix: implement TLS relocation for gas and ld
Add support for TLS in XCOFF. Amongst the things done by this commit:
 - Update XCOFF auxialiary header to match new version and allow TLS
   sections.
 - Add TLS sections (.tdata and .tbss) support in gas and ld.
 - Add support for the TLS relocations in gas and ld.
   Two different types BFD_RELOC are created for PPC and PPC64 as
   the size is a pointer, thus distinct in 32 or 64bit.

The addresses given by ld to .tdata and .tbss is a bit special. In
XCOFF, these addresses are actually offsets from the TLS pointer
computed at runtime. AIX assembly and linker does the same. In
top of that, the .tdata must be before .data (this is mandatory for AIX
loader). Thus, the aix ld script is recomputing "." before .data to restore
its original value. There might be a simpler way, but this one is working.

Optimisation linked to TLS relocations aren't yet implemented.

bfd/
	* reloc.c (BFD_RELOC_PPC_TLS_LE, BFD_RELOC_PPC_TLS_IE,
	BFD_RELOC_PPC_TLS_M, BFD_RELOC_PPC_TLS_ML, BFD_RELOC_PPC64_TLS_GD,
	BFD_RELOC_PPC64_TLS_LD, BFD_RELOC_PPC64_TLS_LE,
	BFD_RELOC_PPC64_TLS_IE, BFD_RELOC_PPC64_TLS_M,
	BFD_RELOC_PPC64_TLS_ML): New relocations.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.
	* coff-rs6000.c (xcoff_calculate_relocation): Call
	xcoff_reloc_type_tls for TLS relocations.
	(xcoff_howto_table): Implement TLS relocations.
	(_bfd_xcoff_reloc_type_lookup): Add cases TLS relocations.
	(xcoff_reloc_type_tls): New function.
	* coff64-rs6000.c (xcoff_calculate_relocation): Likewise.
	(xcoff_howto_table): Likewise.
	(_bfd_xcoff_reloc_type_lookup): Likewise.
	* coffcode.h (sec_to_styp_flags): Handle TLS sections.
	(styp_to_sec_flags): Likewise.
	(coff_compute_section_file_positions): Avoid file offset
	optimisation for .data when the previous section is .tdata.
	(coff_write_object_contents): Handle TLS sections.
	* coffswap.h (coff_swap_aouthdr_out): Add support for
	new fields in aouthdr.
	* libxcoff.h (xcoff_reloc_type_tls): Add prototype.
	* xcofflink.c (xcoff_link_add_symbols): Handle XMC_UL.
	(xcoff_need_ldrel_p): Add cases for TLS relocations.
	(xcoff_create_ldrel): Add l_symndx for TLS sections.
gas/
	* config/tc-ppc.c (ppc_xcoff_text_section, ppc_xcoff_data_section,
	(ppc_xcoff_bss_section, ppc_xcoff_tdata_section,
	(ppc_xcoff_tbss_section): New variables.
	(ppc_text_subsegment, ppc_text_csects, ppc_data_subgments,
	(ppc_data_csects): Removed.
	(ppc_xcoff_section_is_initialized, ppc_init_xcoff_section,
	ppc_xcoff_parse_cons): New functions.
	(md_being): Initialize XCOFF sections.
	(ppc_xcoff_suffix): Add support for TLS relocations
	(fixup_size, md_apply_fix): Add support for new BFD_RELOC.
	(ppc_change_csect): Handle XMC_TL, XMC_UL.  Correctly, add XMC_BS
	to .bss section.  Handle new XCOFF section variables.
	(ppc_comm): Likewise.
	(ppc_toc): Likewise.
	(ppc_symbol_new_hook): Likewise.
	(ppc_frob_symbol): Likewise.
	(ppc_fix_adjustable): Add tbss support.
	* config/tc-ppc.h (TC_PARSE_CONS_EXPRESSION): New define.
	(ppc_xcoff_parse_cons): Add prototype.
	(struct ppc_xcoff_section): New structure.
ld/
	* emultempl/aix.em: Ensure .tdata section is removed
	if empty, even with -r flag.
	* scripttempl/aix.sc: Handle TLS sections.
	* testsuite/ld-powerpc/aix52.exp: Add new tests.
	* testsuite/ld-powerpc/aix-tls-reloc-32.d: New test.
	* testsuite/ld-powerpc/aix-tls-reloc-64.d: New test.
	* testsuite/ld-powerpc/aix-tls-reloc.ex: New test.
	* testsuite/ld-powerpc/aix-tls-reloc.s: New test.
	* testsuite/ld-powerpc/aix-tls-section-32.d: New test.
	* testsuite/ld-powerpc/aix-tls-section-64.d: New test.
	* testsuite/ld-powerpc/aix-tls-section.ex: New test.
	* testsuite/ld-powerpc/aix-tls-section.s: New test.
include/
	* coff/internal.h (struct internal_aouthdr): Add new fields.
	* coff/rs6000.h (AOUTHDRÃ): Add new fields.
	* coff/rs6k64.h (struct external_filehdr): Likewise.
	* coff/xcoff.h (_TDATA), _TBSS): New defines
	(RS6K_AOUTHDR_TLS_LE, RS6K_AOUTHDR_RAS, RS6K_AOUTHDR_ALGNTDATA,
	RS6K_AOUTHDR_SHR_SYMTAB, RS6K_AOUTHDR_FORK_POLICY,
	RS6K_AOUTHDR_FORK_COR): New defines.
	(XMC_TU): Removed.
	(XMC_UL): New define.
2021-03-12 22:47:33 +10:30
..
emulparams Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
emultempl aix: implement TLS relocation for gas and ld 2021-03-12 22:47:33 +10:30
po Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
scripttempl aix: implement TLS relocation for gas and ld 2021-03-12 22:47:33 +10:30
testsuite aix: implement TLS relocation for gas and ld 2021-03-12 22:47:33 +10:30
.gitignore
aclocal.m4 Implement a workaround for GNU mak jobserver 2021-01-12 05:45:44 -08:00
ChangeLog aix: implement TLS relocation for gas and ld 2021-03-12 22:47:33 +10:30
ChangeLog-0001
ChangeLog-0203
ChangeLog-2004
ChangeLog-2005
ChangeLog-2006
ChangeLog-2007
ChangeLog-2008
ChangeLog-2009
ChangeLog-2010
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ChangeLog-2012
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ChangeLog-2014
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ChangeLog-2016
ChangeLog-2017
ChangeLog-2018
ChangeLog-2019
ChangeLog-2020
ChangeLog-9197
ChangeLog-9899
config.in
configure Implement a workaround for GNU mak jobserver 2021-01-12 05:45:44 -08:00
configure.ac Implement a workaround for GNU mak jobserver 2021-01-12 05:45:44 -08:00
configure.host
configure.tgt Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
deffile.h
deffilep.y
dep-in.sed
elf-hints-local.h
fdl.texi
gen-doc.texi
genscrba.sh
genscripts.sh
h8-doc.texi
ld.h
ld.texi PR27451, -z start_stop_gc 2021-03-01 17:28:03 +10:30
ldbuildid.c
ldbuildid.h
ldcref.c
ldctor.c
ldctor.h
ldelf.c elf/x86-64: Subtract __ImageBase for R_AMD64_IMAGEBASE 2021-03-05 18:25:06 -08:00
ldelf.h elf/x86-64: Subtract __ImageBase for R_AMD64_IMAGEBASE 2021-03-05 18:25:06 -08:00
ldelfgen.c bfd, ld, libctf: skip zero-refcount strings in CTF string reporting 2021-03-02 15:10:10 +00:00
ldelfgen.h
ldemul.c
ldemul.h
ldexp.c ld: don't generate base relocations in PE output for absolute symbols 2021-03-04 16:55:01 +01:00
ldexp.h ld: don't generate base relocations in PE output for absolute symbols 2021-03-04 16:55:01 +01:00
ldfile.c
ldfile.h
ldgram.y ld --defsym 2021-02-02 01:27:12 +10:30
ldint.texi
ldlang.c --gc-sections with groups and start/stop syms 2021-03-03 17:46:36 +10:30
ldlang.h SHF_LINK_ORDER fixup_link_order in ld 2021-01-13 22:06:02 +10:30
ldlex-wrapper.c
ldlex.h ld --defsym 2021-02-02 01:27:12 +10:30
ldlex.l ld --defsym 2021-02-02 01:27:12 +10:30
ldmain.c PR27451, -z start_stop_gc 2021-03-01 17:28:03 +10:30
ldmain.h
ldmisc.c
ldmisc.h
ldver.c
ldver.h
ldwrite.c
ldwrite.h
lexsup.c PR27451, -z start_stop_gc 2021-03-01 17:28:03 +10:30
libdep_plugin.c
MAINTAINERS
Makefile.am Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
Makefile.in Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
mri.c
mri.h
NEWS PR27451, -z start_stop_gc 2021-03-01 17:28:03 +10:30
pe-dll.c ld: don't generate base relocations in PE output for absolute symbols 2021-03-04 16:55:01 +01:00
pe-dll.h
pep-dll.c
pep-dll.h
plugin.c
plugin.h
README
stamp-h.in
sysdep.h
testplug2.c
testplug3.c
testplug4.c
testplug.c ld: remove stray debug fprintf 2021-02-18 10:36:39 +00:00
TODO

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		README for LD

This is the GNU linker.  It is distributed with other "binary
utilities" which should be in ../binutils.  See ../binutils/README for
more general notes, including where to send bug reports.

There are many features of the linker:

* The linker uses a Binary File Descriptor library (../bfd)
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* The linker supports a number of different object file
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* The linker can be configured for cross-linking.

* The linker supports a control language.

* There is a user manual (ld.texi), as well as the
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Installation
============

See ../binutils/README.

If you want to make a cross-linker, you may want to specify
a different search path of -lfoo libraries than the default.
You can do this by setting the LIB_PATH variable in ./Makefile
or using the --with-lib-path configure switch.

To build just the linker, make the target all-ld from the top level
directory (one directory above this one).

Porting to a new target
=======================

See the ldint.texi manual.

Reporting bugs etc
===========================

See ../binutils/README.

Known problems
==============

The Solaris linker normally exports all dynamic symbols from an
executable.  The GNU linker does not do this by default.  This is
because the GNU linker tries to present the same interface for all
similar targets (in this case, all native ELF targets).  This does not
matter for normal programs, but it can make a difference for programs
which try to dlopen an executable, such as PERL or Tcl.  You can make
the GNU linker export all dynamic symbols with the -E or
--export-dynamic command line option.

HP/UX 9.01 has a shell bug that causes the linker scripts to be
generated incorrectly.  The symptom of this appears to be "fatal error
- scanner input buffer overflow" error messages.  There are various
workarounds to this:
  * Build and install bash, and build with "make SHELL=bash".
  * Update to a version of HP/UX with a working shell (e.g., 9.05).
  * Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
    genscripts.sh with "sh ${srcdir}..." (no parens) and make sure the
    emulparams script used exports any shell variables it sets.

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