Add support for lzd and popc instructions on sparc.

Add support for lzd and popc instructions on sparc.

gcc/

	* config/sparc/sparc.opt (POPC): New option.
	* doc/invoke.texi: Document it.
	* config/sparc/sparc.c (sparc_option_override): Enable MASK_POPC by
	default on Niagara-2 and later.
	* config/sparc/sparc.h (CLZ_DEFINED_VALUE_AT_ZERO): Define.
	* config/sparc/sparc.md (SIDI): New mode iterator.
	(ffsdi2): Delete commented out pattern and comments.
	(popcount<mode>2, clz<mode>2): New expanders.
	(*popcount<mode>_sp64, popcountsi_v8plus, popcountdi_v8plus,
	*clzdi_sp64, clzdi_v8plus, *clzsi_sp64, clzsi_v8plus): New insns.

gcc/testsuite/

	* gcc.target/sparc/lzd.c: New test.
	* gcc.target/sparc/popc.c: New test.

From-SVN: r179591