Add -z bndplt to generate BND prefix in PLT entries

Add -z bndplt to generate BND prefix in PLT entries

This patch adds "-z bndplt" option Linux/x86-64 linker to generate BND
prefix in PLT entries.  It also updated Linux/x86-64 assembler not to
generate R_X86_64_PLT32_BND nor R_X86_64_PC32_BND relocations.

bfd/

2014-11-18  Igor Zamyatin  <igor.zamyatin@intel.com>

	* elf64-x86-64.c (elf_x86_64_check_relocs): Enable MPX PLT only
	for -z bndplt.

gas/

2014-11-18  Igor Zamyatin  <igor.zamyatin@intel.com>

	* config/tc-i386-intel.c (i386_operator): Remove last argument
	from lex_got call.
	* config/tc-i386.c (reloc): Remove bnd_prefix from parameters'
	list.  Return always BFD_RELOC_32_PCREL.
	* (output_branch): Remove condition for BFD_RELOC_X86_64_PC32_BND.
	* (output_jump): Update call to reloc accordingly.
	* (output_interseg_jump): Likewise.
	* (output_disp): Likewise.
	* (output_imm): Likewise.
	* (x86_cons_fix_new): Likewise.
	* (lex_got): Remove bnd_prefix from parameters' list in macro and
	declarations. Don't use BFD_RELOC_X86_64_PLT32_BND.
	* (x86_cons): Update call to lex_got accordingly.
	* (i386_immediate): Likewise.
	* (i386_displacement): Likewise.
	* (md_apply_fix): Don't use BFD_RELOC_X86_64_PLT32_BND nor
	BFD_RELOC_X86_64_PC32_BND.
	* (tc_gen_reloc): Likewise.

include/

2014-11-18  Igor Zamyatin  <igor.zamyatin@intel.com>

	* bfdlink.h (struct bfd_link_info): Add bndplt.

ld/

2014-11-18  Igor Zamyatin  <igor.zamyatin@intel.com>

	* emulparams/elf_x86_64.sh (BNDPLT): Set to yes for x86_64.
	* emultempl/elf32.em (gld${EMULATION_NAME}_handle_option): Handle
	"-z bndplt" if BNDPLT is yes.
	(gld${EMULATION_NAME}_list_options): Add "-z bndplt" entry.
	* ld.texinfo: Add description for bndplt.

ld/testsuite/

2014-11-18  Igor Zamyatin  <igor.zamyatin@intel.com>

	* testsuite/ld-x86-64/bnd-ifunc-1.d: Add bndplt option.
	* testsuite/ld-x86-64/bnd-ifunc-2.d: Likewise.
	* testsuite/ld-x86-64/bnd-plt-1.d: Likewise.  Update dissassembly
	sections.
	* testsuite/ld-x86-64/mpx.exp: Handle mpx3 and mpx4 tests.
	* testsuite/ld-x86-64/mpx1a.rd: Remove _BND from relocation name.
	* testsuite/ld-x86-64/mpx1c.rd: Likewise.
	* testsuite/ld-x86-64/mpx2a.rd: Likewise.
	* testsuite/ld-x86-64/mpx2c.rd: Likewise.
	* testsuite/ld-x86-64/mpx3.dd: New file.
	* testsuite/ld-x86-64/mpx3a.s: Likewise.
	* testsuite/ld-x86-64/mpx3b.s: Likewise.
	* testsuite/ld-x86-64/mpx4.dd: Likewise.
	* testsuite/ld-x86-64/mpx4a.s: Likewise.
	* testsuite/ld-x86-64/mpx4b.s: Likewise.