* config.gcc: Recognize niagara as target.
	* config/sparc/sparc.h (SPARC_RELAXED_ORDERING): Mention Niagara.
	(TARGET_CPU_niagara): Define.
	(CPP_CPU64_DEFAULT_SPEC): Define __sparc_v9__ for Niagara.
	(ASM_CPU64_DEFAULT_SPEC): Pass -Av9b for Niagara.
	(CPP_CPU_SPEC): Handle -mcpu=niagara.
	(ASM_CPU_SPEC): Likewise.
	(PROCESSOR_NIAGARA): New enum entry.
	(REGISTER_MOVE_COST): Handle Niagara.
	(BRANCH_COST, PREFETCH_BLOCK, SIMULTANEOUS_PREFETCHES): Likewise.
	* config/sparc/sparc.c (niagara_costs): New processor_costs entry.
	(sparc_override_options): Recognize "niagara", set appropriate
	default MASK_* values for it, and align functions to 32-bytes
	by default just like ULTRASPARC/ULTRASPARC3.
	(sparc_initialize_trampoline): Handle niagara like ultrasparc.
	(sparc64_initialize_trampoline): Likewise.
	(sparc_use_sched_lookahead): Use zero for niagara.
	(sparc_issue_rate): Use one for niagara.
	* config/sparc/niagara.md: New file.
	* config/sparc/sparc.md: Include it.
	* config/sparc/sol2-bi.h (CPP_CPU64_DEFAULT_SPEC,
	ASM_CPU32_DEFAULT_SPEC, ASM_CPU64_DEFAULT_SPEC): Set appropriately
	when default cpu is niagara.
	(CPP_CPU_SPEC): Handle -mcpu=niagara.
	(ASM_CPU_SPEC): Likewise.
	* config/sparc/sol2.h (ASM_CPU_DEFAULT_SPEC): Set appropriately
	when default cpu is niagara.
	(ASM_CPU_SPEC): Handle -mcpu=niagara.
	* config/sparc/linux64.h: Handle a default of TARGET_CPU_niagara
	just like v9/ultrasparc/ultrasparc3.
	* doc/invoke.texi: Add documentation for "niagara" and improve
	existing documentation for ultrasparc variants.

From-SVN: r111648