binutils-gdb/ld
H.J. Lu 56ceb5b540 Add R_X86_64_[REX_]GOTPCRELX support to gas and ld
This patch adds support for the R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX relocations proposed in

https://groups.google.com/forum/#!topic/x86-64-abi/n9AWHogmVY0

to gas and ld.  It updates gas to generate R_X86_64_GOTPCRELX,
R_X86_64_REX_GOTPCRELX if there is a REX prefix, relocation for memory
operand, foo@GOTPCREL(%rip).  With the locally defined symbol, foo, we
convert

  mov foo@GOTPCREL(%rip), %reg

to

   lea foo(%rip), %reg

and convert

   call/jmp *foo@GOTPCREL(%rip)
to

   nop call foo/jmp foo nop

When PIC is false, convert

   test %reg, foo@GOTPCREL(%rip)
to

test $foo, %reg

and convert

   binop foo@GOTPCREL(%rip), %reg

to

   binop $foo, %reg

where binop is one of adc, add, and, cmp, or, sbb, sub, xor instructions.

bfd/

	* elf64-x86-64.c: Include opcode/i386.h.
	(x86_64_elf_howto_table): Add R_X86_64_GOTPCRELX and
	R_X86_64_REX_GOTPCRELX.
	(R_X86_64_standard): Replace R_X86_64_PLT32_BND with
	R_X86_64_REX_GOTPCRELX.
	(x86_64_reloc_map): Add BFD_RELOC_X86_64_GOTPCRELX and
	BFD_RELOC_X86_64_REX_GOTPCRELX.
	(need_convert_mov_to_lea): Renamed to ...
	(need_convert_load): This.
	(elf_x86_64_check_relocs): Handle R_X86_64_GOTPCRELX and
	R_X86_64_REX_GOTPCRELX.  Replace need_convert_mov_to_lea with
	need_convert_load.
	(elf_x86_64_gc_sweep_hook): Handle R_X86_64_GOTPCRELX and
	R_X86_64_REX_GOTPCRELX.
	(elf_x86_64_size_dynamic_sections): Likewise.
	(elf_x86_64_relocate_section): Likewise.
	(elf_x86_64_convert_mov_to_lea): Renamed to ...
	(elf_x86_64_convert_load): This.  Replace need_convert_mov_to_lea
	with need_convert_load.  Support R_X86_64_GOTPCRELX and
	R_X86_64_REX_GOTPCRELX transformations.
	* reloc.c (BFD_RELOC_X86_64_GOTPCRELX): New.
	(BFD_RELOC_X86_64_REX_GOTPCRELX): Likewise.
	* bfd-in2.h: Regenerated.
	* libbfd.h: Likewise.

gas/

	* config/tc-i386.c (tc_i386_fix_adjustable): Handle
	BFD_RELOC_X86_64_GOTPCRELX and BFD_RELOC_X86_64_REX_GOTPCRELX.
	(tc_gen_reloc): Likewise.
	(i386_validate_fix): Generate BFD_RELOC_X86_64_GOTPCRELX or
	BFD_RELOC_X86_64_REX_GOTPCRELX if fx_tcbit2 is set.
	* config/tc-i386.h (TC_FORCE_RELOCATION_LOCAL): Also return
	true for BFD_RELOC_X86_64_GOTPCRELX and
	BFD_RELOC_X86_64_REX_GOTPCRELX.

gas/testsuite/

	* gas/i386/i386.exp: Run x86-64-gotpcrel.
	* gas/i386/x86-64-gotpcrel.d: New file.
	* gas/i386/x86-64-gotpcrel.s: Likewise.
	* gas/i386/ilp32/x86-64-gotpcrel.d: Likewise.
	* gas/i386/x86-64-localpic.d: Replace R_X86_64_GOTPCREL with
	R_X86_64_REX_GOTPCRELX.
	* gas/i386/ilp32/x86-64-localpic.d: Likewise.

include/elf/

	* x86-64.h (R_X86_64_GOTPCRELX): New.
	(R_X86_64_REX_GOTPCRELX): Likewise.

ld/testsuite/

	* ld-ifunc/ifunc-5r-local-x86-64.d: Replace R_X86_64_GOTPCREL
	with R_X86_64_REX_GOTPCRELX.
	* ld-x86-64/plt-main1.rd: Likewise.
	* ld-x86-64/plt-main3.rd: Likewise.
	* ld-x86-64/plt-main4.rd: Likewise.
	* ld-x86-64/gotpcrel1.dd: New file.
	* ld-x86-64/gotpcrel1.out: Likewise.
	* ld-x86-64/gotpcrel1a.S: Likewise.
	* ld-x86-64/gotpcrel1b.c: Likewise.
	* ld-x86-64/gotpcrel1c.c: Likewise.
	* ld-x86-64/gotpcrel1d.S: Likewise.
	* ld-x86-64/load1.s: Likewise.
	* ld-x86-64/load1a.d: Likewise.
	* ld-x86-64/load1b.d: Likewise.
	* ld-x86-64/load1c.d: Likewise.
	* ld-x86-64/load1d.d: Likewise.
	* ld-x86-64/x86-64.exp: Run load1a, load1b, load1c and load1d
	tests.  Run gotpcrel1 test.
2015-10-22 04:49:38 -07:00
..
emulparams New ARC implementation. 2015-10-07 14:20:19 +01:00
emultempl New ARC implementation. 2015-10-07 14:20:19 +01:00
po Updated Chinese translation for the linker (again!) 2015-10-14 09:55:30 +01:00
scripttempl New ARC implementation. 2015-10-07 14:20:19 +01:00
testsuite Add R_X86_64_[REX_]GOTPCRELX support to gas and ld 2015-10-22 04:49:38 -07:00
.gitignore
aclocal.m4
ChangeLog Extend description of the --enable-compressed-debug-sections configure option in gas and ld. 2015-10-21 14:57:28 +01:00
ChangeLog-0001
ChangeLog-0203
ChangeLog-2004
ChangeLog-2005
ChangeLog-2006
ChangeLog-2007
ChangeLog-2008
ChangeLog-2009
ChangeLog-2010
ChangeLog-2011
ChangeLog-2012
ChangeLog-2013
ChangeLog-2014
ChangeLog-9197
ChangeLog-9899
config.in Reset x86 Linux targets to not compressing debug sections by default. Enable compression of debug sections by default in the linker, if so configured. 2015-10-21 13:15:39 +01:00
configure Extend description of the --enable-compressed-debug-sections configure option in gas and ld. 2015-10-21 14:57:28 +01:00
configure.ac Extend description of the --enable-compressed-debug-sections configure option in gas and ld. 2015-10-21 14:57:28 +01:00
configure.host
configure.tgt New ARC implementation. 2015-10-07 14:20:19 +01:00
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: Extend options for altering orphan handling behaviour. 2015-09-04 22:30:55 +01:00
ld.texinfo Reset x86 Linux targets to not compressing debug sections by default. Enable compression of debug sections by default in the linker, if so configured. 2015-10-21 13:15:39 +01:00
ldbuildid.c
ldbuildid.h
ldcref.c
ldctor.c
ldctor.h
ldemul.c ld: Extend options for altering orphan handling behaviour. 2015-09-04 22:30:55 +01:00
ldemul.h
ldexp.c When evaluating a ternary operator in a linker script, copy the symbol flags. 2015-10-15 13:28:27 +01:00
ldexp.h Delay converting linker script defined symbols from absolute 2015-09-18 12:39:16 +09:30
ldfile.c
ldfile.h
ldgram.y
ldint.texinfo
ldlang.c Delay converting linker script defined symbols from absolute 2015-09-18 12:39:16 +09:30
ldlang.h
ldlex-wrapper.c
ldlex.h Add --no-dynamic-linker option to ld, for static PIE use 2015-09-20 15:52:27 +09:30
ldlex.l
ldmain.c Reset x86 Linux targets to not compressing debug sections by default. Enable compression of debug sections by default in the linker, if so configured. 2015-10-21 13:15:39 +01:00
ldmain.h
ldmisc.c
ldmisc.h
ldver.c
ldver.h
ldwrite.c
ldwrite.h
lexsup.c Reset x86 Linux targets to not compressing debug sections by default. Enable compression of debug sections by default in the linker, if so configured. 2015-10-21 13:15:39 +01:00
MAINTAINERS
Makefile.am New ARC implementation. 2015-10-07 14:20:19 +01:00
Makefile.in New ARC implementation. 2015-10-07 14:20:19 +01:00
mri.c
mri.h
NEWS Reset x86 Linux targets to not compressing debug sections by default. Enable compression of debug sections by default in the linker, if so configured. 2015-10-21 13:15:39 +01:00
pe-dll.c
pe-dll.h
pep-dll.c
pep-dll.h
plugin.c
plugin.h
README
stamp-h.in
sysdep.h
testplug2.c
testplug3.c
testplug.c
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)
  that it uses to read and write object files.  This helps
  insulate the linker itself from the format of object files.

* The linker supports a number of different object file
  formats.  It can even handle multiple formats at once:
  Read two input formats and write a third.

* The linker can be configured for cross-linking.

* The linker supports a control language.

* There is a user manual (ld.texinfo), as well as the
  beginnings of an internals manual (ldint.texinfo).

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.texinfo 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.

Copyright (C) 2012-2015 Free Software Foundation, Inc.

Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.