* 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.