rs6000-protos.h (expand_strn_compare): Add arg.

rs6000-protos.h (expand_strn_compare): Add arg.

2017-01-18  Aaron Sawdey  <acsawdey@linux.vnet.ibm.com>
	* config/rs6000/rs6000-protos.h (expand_strn_compare): Add arg.
	* config/rs6000/rs6000.c (expand_strn_compare): Add ability to expand
	strcmp. Fix bug where comparison didn't stop with zero byte. Fix
	case where N arg is SIZE_MAX.
	* config/rs6000/rs6000.md (cmpstrnsi): Args to expand_strn_compare.
	(cmpstrsi): Add pattern.
2017-01-18  Aaron Sawdey  <acsawdey@linux.vnet.ibm.com>
	* gcc.dg/strcmp-1.c: New test.
	* gcc.dg/strncmp-1.c: Add test for a bug that escaped.

From-SVN: r244598