unwind-ia64.c (struct _Unwind_Context): Add new field 'signal_pfs_loc'.

unwind-ia64.c (struct _Unwind_Context): Add new field 'signal_pfs_loc'.

	* config/ia64/unwind-ia64.c (struct _Unwind_Context): Add new
	field 'signal_pfs_loc'.
	(uw_frame_state_for): Remove duplicate code dealing with leaf
	procedures without unwind info.
	If in the frame after unwinding through a signal handler, restore
	the AR.PFS register instead of the CFM if AR.PFS has not been saved.
	* config/ia64/linux-unwind.h (ia64_fallback_frame_state): Do not set
	'pfs_loc' to the AR.PFS location in the signal context; instead
	set 'signal_pfs_loc'.
	Manually generate the unwind info for the AR.PFS register.
	(ABI_MARKER_OLD_LINUX_SIGTRAMP, ABI_MARKER_OLD_LINUX_INTERRUPT,
	ABI_MARKER_LINUX_SIGTRAMP, ABI_MARKER_LINUX_INTERRUPT): Define.
	(ia64_handle_unwabi): Test 'fs->unwabi' against them.
	Do not set 'pfs_loc' to the AR.PFS location in the signal context;
	instead set 'signal_pfs_loc'.
	Remove code preventing the AR.PFS register from being restored
	from the signal context.

From-SVN: r150777