* builtin-types.def (BT_FN_FLOAT_FLOAT_FLOAT): New built-in type.
	(BT_FN_LONG_DOUBLE_LONG_DOUBLE_LONG_DOUBLE): Likewise.
	(BT_FN_DOUBLE_DOUBLE_DOUBLE): Likewise.
	* builtins.def: Define pow, powf, powl, atan2, atan2f and atan2l
	builtin functions (and their __builtin_* variants).
	* builtins.c (mathfn_built_in): Handle missing log{,f,l} cases.
	(expand_builtin): Don't expand log{,f,l}, pow{,f,l} or atan2{,f,l}
	when not optimizing.

	* doc/extend.texi: Document new pow and atan2 builtins, and
	their float and long double variants.  Realphabetize builtins.

	* testsuite/gcc.dg/builtins-4.c: New test case.

From-SVN: r62551