2004-08-12 Andreas Krebbel <krebbel1@de.ibm.com>

	* config/s390/s390.c (struct s390_frame_layout): New struct as element
	of struct machine_function.
	(cfun->machine->frame_size): Moved into cfun->machine->frame_layout and
	changed all uses.
	(cfun->machine->save_fprs_p): Replaced by cfun_save_high_fprs and
	changed all uses.
	(cfun_frame_layout, cfun_save_high_fprs_p, cfun_gprs_save_area_size)
	(cfun_set_fpr_bit, cfun_fpr_bit_p): New macros.
	(s390_frame_area, s390_register_info): New functions.
	(s390_optimize_prolog): Renamed to s390_optimize_prologue.  Added check
	for base register.
	(s390_return_addr_rtx, s390_return_address_offset)
	(s390_va_start, s390_gimplify_va_arg)
	(s390_emit_prologue, s390_emit_epilogue): Adjusted for new stack
	layouts.
	(s390_frame_info): Functionality partly moved to s390_register_info.
	Made adaptions for new stack layout.
	(save_gprs, restore_gprs): Changed meaning of second parameter and
	adapted all callers.

	* config/s390/s390.h (s390_backchain_string): New global variable.
	(MASK_BACKCHAIN): Removed definition.
	(TARGET_BACKCHAIN): Changed check.
	(TARGET_KERNEL_BACKCHAIN): New macro.
	(TARGET_SWITCHES): Removed entries of "backchain" and "no-backchain".
	(TARGET_OPTIONS): Added "backchain", "no-backchain" and
	"kernel-backchain".
	(DYNAMIC_CHAIN_ADDRESS): Adjusted for new stack layouts.

	* config/s390/s390.md ("allocate_stack"): Added TARGET_KERNEL_BACKCHAIN
	as condition.  Adjusted for new stack layout.

	* doc/invoke.texi: Added documentation for new option
	"-mkernel-backchain" and adjusted documentation of "-mbackchain" and
	"-mno-backchain".


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@85882 138bc75d-0d04-0410-961f-82ee72b054a4