* emulparams/elf64alpha.sh (PLT): New.
(TEXT_PLT): New.
* emultempl/alphaelf.em (disable_relaxation): New.
(limit_32bit): Rename from elf64alpha_32bit; update all users.
(elf64_alpha_use_secureplt): Declare.
(bfd_elf64_alpha_vec, bfd_elf64_alpha_freebsd_vec): Declare.
(alpha_after_open): New.
(alpha_before_allocation): New.
(OPTION_NO_RELAX, OPTION_SECUREPLT, OPTION_NO_SECUREPLT): New.
(PARSE_AND_LIST_LONGOPTS): Include them.
(PARSE_AND_LIST_OPTIONS): Likewise.
(PARSE_AND_LIST_ARGS_CASES): Likewise.
(LDEMUL_AFTER_OPEN, LDEMUL_BEFORE_ALLOCATION): New.
* scripttempl/elf.sc (TEXT_PLT): New.
(PLT): Use it.