ia64 prologue/epilogue rewrite 4/4

[Richard Henderson <rth at cygnus dot com>]

This was still way bigger than I hoped, but there's prolly
little for it.  Highlights:

  * Prologue/epilogue now uses dual post_modify iterators
    to do two memory references in parallel on large frames.
  * Register stack avoided on leaf functions that require
    a frame pointer, but still have global regs unused.
  * Application registers (ar.lc, ar.unat, etc) saved to
    unused general regs instead of the stack when possible.
  * ar.pfs not saved/restored for leaf functions.
  * non-local gotos work without a frame pointer.
  * trampolines work reliably (not exactly sure what the problem was,
    but the new implementation is lots smaller, and understandable).
  * exception handling should work across shared libraries.
  * some general pattern and comment cleanup.
  

r~
  

	* config/ia64/ia64-protos.h: Remove duplicates.  Update
	for massive code rearrangements.
	* config/ia64/ia64.c (ia64_arpfs_regno): Remove.
	(ia64_rp_regno, ia64_fp_regno, ia64_input_regs): Remove.
	(ia64_local_regs, ia64_need_regstk): Remove.
	(ar_ccv_reg_operand): New.
	(ia64_gp_save_reg): New.
	(struct ia64_frame_info): Combine most of the size elements;
	add new gr save elements.
	(find_gr_spill): New.
	(next_scratch_gr_reg): New.
	(mark_reg_gr_used_mask): New.
	(ia64_compute_frame_size): Rewrite.  Allocate special AR regs
	to GR backing store regs when possible.
	(ia64_initial_elimination_offset): New.
	(ia64_rap_fp_offset): Remove.
	(save_restore_insns): Remove.
	(setup_spill_pointers): New.
	(finish_spill_pointers): New.
	(spill_restore_mem): New.
	(do_spill, do_restore): New.
	(ia64_expand_prologue): Rewrite to use them.
	(ia64_expand_epilogue): Likewise.
	(ia64_direct_return): Update for current_frame_info changes.
	(ia64_function_prologue): Simplify .prologue emission.  Emit
	.spill when needed.
	(ia64_setup_incoming_varargs): Don't ever emit rtl.
	(ia64_dbx_register_number): New.
	(ia64_initialize_trampoline): New.
	(ia64_secondary_reload_class): Request GR_REGS for integer
	arithmetic destined for FR_REGS.
	(ia64_init_machine_status): Don't reset return_address_pointer_rtx.
	(ia64_mark_machine_status): Mark ia64_gp_save.
	(rws_access_regno): Rename from rws_access_reg; don't treat
	predicates specially.
	(rws_access_reg): New.  Update all callers.
	(rtx_needs_barrier): Remove dead unspecs.
	(ia64_epilogue_uses): Mark ar.pfs and ar.unat live on exit.
	(ia64_encode_section_info): Silence signed/unsigned warnings.
	(spill_offset, sp_offset, spill_offset_emitted): Remove.
	(tmp_reg, tmp_saved): Remove.
	(process_set): Rewrite to expect complicated bits via 
	REG_FRAME_RELATED_EXPR.
	(ia64_expand_fetch_and_op): Use emit_move_insn; be explicit
	in the use of ar.ccv; never set RTX_UNCHANGING_P.
	(ia64_expand_op_and_fetch): Likewise.
	(ia64_expand_compare_and_swap): Likewise.
	(ia64_expand_builtin): Likewise.
	* config/ia64/ia64.h (AR_UNAT_REGNUM): New.
	(FIRST_PSEUDO_REGISTER): Update.
	(AR_M_REGNO_P): Update.
	(FIXED_REGS): Don't mark three local registers as used.
	(EXTRA_CC_MODES): New.
	(SELECT_CC_MODE): New.
	(HARD_REGNO_NREGS): Allow DImode in p0; handle CCImode.
	(HARD_REGNO_MODE_OK): Disallow CCImode from non-predicates.
	(FRAME_GROWS_DOWNWARD): Unset.
	(STARTING_FRAME_OFFSET): Zero.
	(ELIMINABLE_REGS): Eliminate from the soft to hard frame pointer.
	(INITIAL_ELIMINATION_OFFSET): Defer to out of line function.
	(HARD_FRAME_POINTER_REGNUM): New.
	(CAN_DEBUG_WITHOUT_FP): Define.
	(TRAMPOLINE_TEMPLATE): Remove.
	(TRAMPOLINE_SIZE): Lower to 32.
	(TRAMPOLINE_ALIGNMENT): Lower to 64.
	(INITIALIZE_TRAMPOLINE): Defer to out of line function.
	(PREDICATE_CODES): Update.
	(struct machine_function): Add ia64_gp_save.
	* config/ia64/ia64.md: Purge unused unspecs.
	(movsi patterns): Allow moves to/from AR_M_REGS.
	(movdi patterns): Allow moves to/from p0.
	(call patterns): Move most setjmp hackery to ia64_gp_save_reg.
	(gr_spill, gr_restore): Indicate ar.unat read/written.
	(nonlocal_goto): Don't pass old frame_pointer.
	(nonlocal_goto_receiver): Remove.
	(exception_receiver): New.
	(builtin_setjmp_setup): New.
	(builtin_setjmp_receiver): New.
	* config/ia64/lib1funcs.asm (__ia64_save_stack_nonlocal): Bundle.
	(__ia64_nonlocal_goto): Bundle.  Don't kill r7.
	(__ia64_restore_stack_nonlocal): Likewise.
	(__ia64_trampoline): New.
	* config/ia64/sysv4.h (DBX_REGISTER_NUMBER): Defer to out of line
	function.
	* config/ia64/t-ia64 (LIB1ASMFUNCS): Add __trampoline.

z-bulk-prologue.gz