Add SB-1A support.

Add SB-1A support.

* config/mips/mips.md (cpu): Add sb1a.
* config/mips/sb1.md: Modify almost all patterns to accept sb1a in
addition to sb1.  Adjust comments to clarify SB-1A differences from
SB-1.
(ir_sb1a_load): New.  Modify bypasses to use it.
(ir_sb1a_simple_alu): Likewise.
* config/mips/mips.c (mips_cpu_info_table): Add sb1a.
(mips_rtx_cost_data): Add PROCESSOR_SB1A support.
(mips_issue_rate): Add PROCESSOR_SB1A.
(mips_multipass_dfa_lookahead): Use TUNE_SB1 instead of PROCESSOR_SB1.
* config/mips/mips.h (processor_type): Add PROCESSOR_SB1A.
(TARGET_SB1): Add PROCESSOR_SB1A check.
(TUNE_SB1): Likewise.
* config/mips/mips-protos.h (mips_store_data_bypass_p): New.
* config/mips/mips.c (mips_store_data_bypass_p): New.
* config/mips/sb1.md: Use mips_store_data_bypass_p instead of
store_data_bypass_p.

From-SVN: r115274