2015-07-14  Sandra Loosemore  <sandra@codesourcery.com>
	    Cesar Philippidis  <cesar@codesourcery.com>
	    Chung-Lin Tang  <cltang@codesourcery.com>

	gcc/
	* config/nios2/nios2.h (SMALL_INT12): New macro.
	* config/nios2/nios2.c (nios2_valid_addr_offset_p): New function.
	(nios2_valid_addr_expr_p): Use it.
	(nios2_symbol_ref_in_small_data_p): Disallow GP-relative addressing
	with implicit "io" instructions on R2.
	* config/nios2/constraints.md (w): New constraint.
	* config/nios2/predicates.md (ldstio_memory_operand): New.
	* config/nios2/nios2.md (ld<bhw_uns>io, ld<bh>io): Update memory
	operand predicate and constraint.
	(ld<bh>io_signed, st<bhw>io>): Likewise.
	* doc/md.texi (Machine Constraints): Document w constraint.

	gcc/testsuite/
	* gcc.target/nios2/r2-io-range.c: New.
	* gcc.target/nios2/r2-stio-1.c: New.
	* gcc.target/nios2/r2-stio-2.c: New.
	* gcc.target/nios2/nios2-ldxio.c: New.
	* gcc.target/nios2/nios2-stxio.c: Change to assemble test instead
	of just compile.  Add more tests.

Co-Authored-By: Cesar Philippidis <cesar@codesourcery.com>
Co-Authored-By: Chung-Lin Tang <cltang@codesourcery.com>

From-SVN: r225792