[binutils-gdb] Support i386 TLS code sequences without PLT

[sergiodj+buildbot at sergiodj dot net]

*** TEST RESULTS FOR COMMIT 6eaa7fb59b32beaca017abf139a67bbe87592d9b ***

Author: H.J. Lu <hjl.tools@gmail.com>
Branch: master
Commit: 6eaa7fb59b32beaca017abf139a67bbe87592d9b

Support i386 TLS code sequences without PLT

We can generate i386 TLS code sequences for general and local dynamic
models without PLT, which uses indirect call via GOT:

call *___tls_get_addr@GOT(%reg)

where EBX register isn't required as GOT base, instead of direct call:

call ___tls_get_addr[@PLT]

which requires EBX register as GOT base.

Since direct call is 4-byte long and indirect call, is 5-byte long, the
extra one byte must be handled properly.

For general dynamic model, 7-byte lea instruction before call instruction
is replaced by 6-byte one to make room for indirect call.  For local
dynamic model, we simply use 5-byte indirect call.

TLS linker optimization is updated to recognize new instruction patterns.
For local dynamic model to local exec model transition, we generate
a 6-byte lea instruction as nop, instead of a 1-byte nop plus a 4-byte
lea instruction.  Since linker may convert

call ___tls_get_addr[@PLT]

to

addr32 call ____tls_get_addr

when producing static executable, both patterns are recognized.

bfd/

	* elf64-i386.c (elf_i386_link_hash_entry): Add tls_get_addr.
	(elf_i386_link_hash_newfunc): Initialize tls_get_addr to 2.
	(elf_i386_check_tls_transition): Check indirect call and direct
	call with the addr32 prefix for general and local dynamic models.
	Set the tls_get_addr feild.
	(elf_i386_convert_load_reloc): Always use addr32 prefix for
	indirect ___tls_get_addr call via GOT.
	(elf_i386_relocate_section): Handle GD->LE, GD->IE and LD->LE
	transitions with indirect call and direct call with the addr32
	prefix.

ld/

	* testsuite/ld-i386/i386.exp: Run libtlspic2.so, tlsbin2,
	tlsgd3, tlsld2, tlsgd4, tlspie3a, tlspie3b and tlspie3c.
	* testsuite/ld-i386/pass.out: New file.
	* testsuite/ld-i386/tls-def1.c: Likewise.
	* testsuite/ld-i386/tls-gd1.S: Likewise.
	* testsuite/ld-i386/tls-ld1.S: Likewise.
	* testsuite/ld-i386/tls-main1.c: Likewise.
	* testsuite/ld-i386/tls.exp: Likewise.
	* testsuite/ld-i386/tlsbin2-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsbin2.dd: Likewise.
	* testsuite/ld-i386/tlsbin2.rd: Likewise.
	* testsuite/ld-i386/tlsbin2.sd: Likewise.
	* testsuite/ld-i386/tlsbin2.td: Likewise.
	* testsuite/ld-i386/tlsbinpic2.s: Likewise.
	* testsuite/ld-i386/tlsgd3.dd: Likewise.
	* testsuite/ld-i386/tlsgd3.s: Likewise.
	* testsuite/ld-i386/tlsgd4.d: Likewise.
	* testsuite/ld-i386/tlsgd4.s: Likewise.
	* testsuite/ld-i386/tlsld2.s: Likewise.
	* testsuite/ld-i386/tlspic2-nacl.rd: Likewise.
	* testsuite/ld-i386/tlspic2.dd: Likewise.
	* testsuite/ld-i386/tlspic2.rd: Likewise.
	* testsuite/ld-i386/tlspic2.sd: Likewise.
	* testsuite/ld-i386/tlspic2.td: Likewise.
	* testsuite/ld-i386/tlspic3.s: Likewise.
	* testsuite/ld-i386/tlspie3.s: Likewise.
	* testsuite/ld-i386/tlspie3a.d: Likewise.
	* testsuite/ld-i386/tlspie3b.d: Likewise.
	* testsuite/ld-i386/tlspie3c.d: Likewise.