* optabs.h (enum optab_index): Add new OTI_ldexp.
	(ldexp_optab): Define corresponding macro.
	* optabs.c (init_optabs): Initialize ldexp_optab.
	* genopinit.c (optabs): Implement ldexp_optab using ldexp?f3
	patterns.
	* builtins.c (expand_builtin_mathfn_2): Handle BUILT_IN_LDEXP{,F,L}
	using ldexp_optab.
	(expand_builtin): Expand BUILT_IN_LDEXP{,F,L} using
	expand_builtin_mathfn_2 if flag_unsafe_math_optimizations is set.

	* config/i386/i386.md (ldexpsf3, ldexpdf3, ldexpxf3): New expanders
	to implement ldexpf, ldexp and ldexpl built-ins as inline x87
	intrinsics.

testsuite:

	* gcc.dg/builtins-34.c: Also check ldexp*.

From-SVN: r94931