Add support for the R6 LSA and DLSA instructions

Add support for the R6 LSA and DLSA instructions

gcc/

	* config/mips/mips.c (mips_rtx_costs): Set costs for LSA/DLSA.
	(mips_print_operand): Support 'y' to print exact log2 in decimal
	of a const_int.
	* config/mips/mips.h (ISA_HAS_LSA): New define.
	(ISA_HAS_DLSA): Likewise.
	* config/mips/mips.md (<GPR:d>lsa): New define_insn.
	* config/mips/predicates.md (const_immlsa_operand): New predicate.

gcc/testsuite/

	* gcc.target/mips/lsa.c: New file.
	* gcc.target/mips/mips64-lsa.c: Likewise.
	* gcc.target/mips/mulsize-2.c: Require !HAS_LSA.
	* gcc.target/mips/mulsize-4.c: Likewise.
	* gcc.target/mips/mulsize-5.c: New file.
	* gcc.target/mips/mulsize-6.c: Likewise.
	* gcc.target/mips/mips.exp (mips_option_groups): Support HAS_LSA
	and !HAS_LSA as ghost options.
	(mips-dg-options): Require rev 6 for HAS_LSA. Downgrade to rev 5
	for !HAS_LSA.

From-SVN: r219638