[ARC] Avoid specific constants to end in limm field.

[ARC] Avoid specific constants to end in limm field.

Avoid constants to end up in the limm field for particular
instructions when compiling for size.

gcc/
xxxx-xx-xx  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/arc/arc.md (*add_n): Clean up pattern, update instruction
	constraints.
	(ashlsi3_insn): Update instruction constraints.
	(ashrsi3_insn): Likewise.
	(rotrsi3): Likewise.
	(add_shift): Likewise.
	* config/arc/constraints.md (Csz): New 32 bit constraint. It
	avoids placing in the limm field small constants which, otherwise,
	could end into a small instruction.

testsuite/
xxxx-xx-xx  Claudiu Zissulescu  <claziss@synopsys.com>

	* gcc.target/arc/tph_addx.c: New test.

From-SVN: r264737