[ix86/gcc-4_4-branch]: Backport the first Atom patch

[H.J. Lu]

Hi,

I backported the first Atom patch from mainline to
ix86/gcc-4_4-branch.


-- 
H.J.
---
2009-04-06  H.J. Lu  <hongjiu.lu@intel.com>

	Backport from mainline:
	2009-04-06  Joey Ye  <joey.ye@intel.com>
		    Xuepeng Guo <xuepeng.guo@intel.com>
		    H.J. Lu  <hongjiu.lu@intel.com>

	Atom pipeline model, tuning and insn selection.
	* config.gcc (atom): Add atom config options and target.

	* config/i386/atom.md: New.

	* config/i386/i386.c (atom_cost): New cost.
	(m_ATOM): New macro flag.
	(initial_ix86_tune_features): Set m_ATOM.
	(x86_accumulate_outgoing_args): Likewise.
	(x86_arch_always_fancy_math_387): Likewise.
	(processor_target): Add Atom cost.
	(cpu_names): Add Atom cpu name.
	(override_options): Set Atom ISA.
	(ix86_issue_rate): New case PROCESSOR_ATOM.
	(ix86_adjust_cost): Likewise.

	* config/i386/i386.h (TARGET_ATOM): New target macro.
	(ix86_tune_indices): Add X86_TUNE_OPT_AGU.
	(TARGET_OPT_AGU): New target option.
	(target_cpu_default): Add TARGET_CPU_DEFAULT_atom.
	(processor_type): Add PROCESSOR_ATOM.

	* config/i386/i386.md (cpu): Add new value "atom".
	(use_carry, movu): New attr.
	(atom.md): Include atom.md.
	(adddi3_carry_rex64): Set attr "use_carry".
	(addqi3_carry): Likewise.
	(addhi3_carry): Likewise.
	(addsi3_carry): Likewise.
	(*addsi3_carry_zext): Likewise.
	(subdi3_carry_rex64): Likewise.
	(subqi3_carry): Likewise.
	(subhi3_carry): Likewise.
	(subsi3_carry): Likewise.
	(x86_movdicc_0_m1_rex64): Likewise.
	(*x86_movdicc_0_m1_se): Likewise.
	(x86_movsicc_0_m1): Likewise.
	(*x86_movsicc_0_m1_se): Likewise.
	(*adddi_1_rex64): Emit add insn as much as possible.
	(*addsi_1): Likewise.
	(return_internal): Set atom_unit.
	(return_internal_long): Likewise.
	(return_pop_internal): Likewise.
	(*rcpsf2_sse): Set atom_sse_attr attr.
	(*qrt<mode>2_sse): Likewise.