* config/s390/s390-protos.h (s390_load_got): Update prototype.
	* config/s390/s390.c (struct machine_function): Add member base_reg.
	(s390_decompose_address): Accept UNSPEC_LTREF.  Simplify logic.
	(s390_split_branches): Annotate late pool references.
	(annotate_constant_pool_refs): New function.
	(find_constant_pool_ref): Work on annotated pool references.
	(replace_constant_pool_ref): Likewise.  Use explicit base.
	(replace_ltrel_base): Use explicit base.
	(s390_mainpool_start): Reflect main_pool pattern change.
	(s390_mainpool_finish): Use base register from main_pool.
	Update calls to replace_ltrel_base and replace_constant_pool_ref.
	(s390_chunkify_start): Use base_reg from struct machine_function.
	(s390_chunkify_finish): Remove base_reg argument.  Update calls
	to replace_ltrel_base and replace_constant_pool_ref.
	(s390_reorg): Don't decide upon base register.  Update calls.
	(s390_load_got): Remove MAYBE_DEAD handling.  Do not emit insns
	but return sequence instead.
	(s390_emit_prologue): Decide upon base register to use.  Annotate
	all literal pool references.  Adapt to main_pool pattern change.
	Update s390_load_got call; move MAYBE_DEAD handling here.
	(s390_emit_epilogue): Annotate late literal pool references.
	Remove barrier before register restore instruction.
	* config/s390/s390.md (UNSPEC_LTREF): New constant.
	("builtin_setjmp_receiver"): Update s390_load_got call.
	("main_pool"): Explicitly reference base register.

From-SVN: r83735