binutils-gdb/ld
Alan Modra c213164ad2 [PowerPC64] pc-relative TLS relocations
This patch supports using pcrel instructions in TLS code sequences.  A
number of new relocations are needed, gas operand modifiers to
generate those relocations, and new TLS optimisation.  For
optimisation it turns out that the new pcrel GD and LD sequences can
be distinguished from the non-pcrel GD and LD sequences by there being
different relocations on the new sequence.  The final "add ra,rb,13"
on IE sequences similarly needs a new relocation, or as I chose, a
modification of R_PPC64_TLS.  On pcrel IE code, the R_PPC64_TLS points
one byte into the "add" instruction rather than being on the
instruction boundary.

GD:
 pla 3,z@got@tlsgd@pcrel	  # R_PPC64_GOT_TLSGD34
 bl __tls_get_addr@notoc(z@tlsgd) # R_PPC64_TLSGD and R_PPC64_REL24_NOTOC
  edited to IE
   pld 3,z@got@tprel@pcrel
   add 3,3,13
  edited to LE
   paddi 3,13,z@tprel
   nop

LD:
 pla 3,z@got@tlsld@pcrel	  # R_PPC64_GOT_TLSLD34
 bl __tls_get_addr@notoc(z@tlsld) # R_PPC64_TLSLD and R_PPC64_REL24_NOTOC
 ..
 paddi 9,3,z2@dtprel
 pld 10,z3@got@dtprel@pcrel
 add 10,10,3
  edited to LE
   paddi 3,13,0x1000
   nop

IE:
 pld 9,z@got@tprel@pcrel	  # R_PPC64_GOT_TPREL34
 add 3,9,z@tls@pcrel		  # R_PPC64_TLS at insn+1
 ldx 4,9,z@tls@pcrel
 lwax 5,9,z@tls@pcrel
 stdx 5,9,z@tls@pcrel
  edited to LE
  paddi 9,13,z@tprel
  nop
  ld 4,0(9)
  lwa 5,0(9)
  std 5,0(9)

LE:
 paddi 10,13,z@tprel

include/
	* elf/ppc64.h (R_PPC64_TPREL34, R_PPC64_DTPREL34),
	(R_PPC64_GOT_TLSGD34, R_PPC64_GOT_TLSLD34),
	(R_PPC64_GOT_TPREL34, R_PPC64_GOT_DTPREL34): Define.
	(IS_PPC64_TLS_RELOC): Include new tls relocs.
bfd/
	* reloc.c (BFD_RELOC_PPC64_TPREL34, BFD_RELOC_PPC64_DTPREL34),
	(BFD_RELOC_PPC64_GOT_TLSGD34, BFD_RELOC_PPC64_GOT_TLSLD34),
	(BFD_RELOC_PPC64_GOT_TPREL34, BFD_RELOC_PPC64_GOT_DTPREL34),
	(BFD_RELOC_PPC64_TLS_PCREL): New pcrel tls relocs.
	* elf64-ppc.c (ppc64_elf_howto_raw): Add howtos for pcrel tls relocs.
	(ppc64_elf_reloc_type_lookup): Translate pcrel tls relocs.
	(must_be_dyn_reloc, dec_dynrel_count): Add R_PPC64_TPREL64.
	(ppc64_elf_check_relocs): Support pcrel tls relocs.
	(ppc64_elf_tls_optimize, ppc64_elf_relocate_section): Likewise.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.
gas/
	* config/tc-ppc.c (ppc_elf_suffix): Map "tls@pcrel", "got@tlsgd@pcrel",
	"got@tlsld@pcrel", "got@tprel@pcrel", and "got@dtprel@pcrel".
	(fixup_size, md_assemble): Handle pcrel tls relocs.
	(ppc_force_relocation, ppc_fix_adjustable): Likewise.
	(md_apply_fix, tc_gen_reloc): Likewise.
ld/
	* testsuite/ld-powerpc/tlsgd.d,
	* testsuite/ld-powerpc/tlsgd.s,
	* testsuite/ld-powerpc/tlsie.d,
	* testsuite/ld-powerpc/tlsie.s,
	* testsuite/ld-powerpc/tlsld.d,
	* testsuite/ld-powerpc/tlsld.s: New tests.
	* testsuite/ld-powerpc/powerpc.exp: Run them.
2019-07-19 18:01:25 +09:30
..
emulparams s12z genelf.em 2019-05-30 01:01:42 +09:30
emultempl ld -r: Don't merge with member of output section group 2019-07-18 08:01:54 -07:00
po Regen POTFILES for bpf 2019-05-24 23:15:07 +09:30
scripttempl Use the correct names for the init and fini array start symbols in the default Pru linker script. 2019-05-09 10:26:11 +01:00
testsuite [PowerPC64] pc-relative TLS relocations 2019-07-19 18:01:25 +09:30
.gitignore
aclocal.m4
ChangeLog [PowerPC64] pc-relative TLS relocations 2019-07-19 18:01:25 +09:30
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-2015
ChangeLog-2016
ChangeLog-2017
ChangeLog-2018
ChangeLog-9197
ChangeLog-9899
config.in
configure Regenerate with approved autotools version 2019-06-14 10:30:35 +09:30
configure.ac Automatic makefile dependencies for generated ld/e*.c 2019-04-13 12:13:22 +09:30
configure.host
configure.tgt ld: add support for eBPF 2019-05-23 19:34:15 +02:00
deffile.h
deffilep.y
dep-in.sed
elf-hints-local.h
fdl.texi
gen-doc.texi
genscrba.sh Automatic makefile dependencies for generated ld/e*.c 2019-04-13 12:13:22 +09:30
genscripts.sh Fix automatic makefile dependencies for generated ld/e*.c 2019-04-23 17:02:44 +09:30
h8-doc.texi
ld.h ld: Add --no-print-map-discarded option 2019-04-11 10:16:31 -07:00
ld.texi LD/doc: Clarify `-rpath' option's semantics WRT link-time dependencies 2019-06-07 19:25:21 +01:00
ldbuildid.c Fix compile time warning when building the linker in a MinGw32 environment using gcc 8. 2019-05-08 16:54:16 +01:00
ldbuildid.h
ldcref.c
ldctor.c
ldctor.h
ldemul.c
ldemul.h
ldexp.c Allow the use of the ORIGIN and LENGTH attributes in expressions inside MEMORY regions. 2019-03-06 15:20:29 +00:00
ldexp.h
ldfile.c Re: Have the linker report an error if the same script is used twice 2019-05-23 10:38:45 +09:30
ldfile.h Have the linker report an error if the same script is used twice. 2019-05-22 15:58:57 +01:00
ldgram.y
ldint.texi
ldlang.c PR24786, wrong LMA if first section in overlay is empty 2019-07-13 09:57:50 +09:30
ldlang.h PR24786, wrong LMA if first section in overlay is empty 2019-07-13 09:57:50 +09:30
ldlex-wrapper.c
ldlex.h ld: Add --no-print-map-discarded option 2019-04-11 10:16:31 -07:00
ldlex.l PR24411, Division is not accepted in MEMORY length expression 2019-04-03 13:01:49 +10:30
ldmain.c Have the linker report an error if the same script is used twice. 2019-05-22 15:58:57 +01:00
ldmain.h
ldmisc.c
ldmisc.h
ldver.c
ldver.h
ldwrite.c
ldwrite.h
lexsup.c Have the linker report an error if the same script is used twice. 2019-05-22 15:58:57 +01:00
MAINTAINERS
Makefile.am ld: add support for eBPF 2019-05-23 19:34:15 +02:00
Makefile.in Regenerate with approved autotools version 2019-06-14 10:30:35 +09:30
mri.c
mri.h
NEWS [LD, AArch64] Move ELF options behind -z 2019-06-06 12:21:14 +01:00
pe-dll.c
pe-dll.h
pep-dll.c
pep-dll.h
plugin.c ld/plugins: avoid shadowing a C library symbol 2019-06-25 12:02:23 +02:00
plugin.h
README
stamp-h.in
sysdep.h
testplug2.c
testplug3.c
testplug4.c
testplug.c
TODO

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		README for LD

This is the GNU linker.  It is distributed with other "binary
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HP/UX 9.01 has a shell bug that causes the linker scripts to be
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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).
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