PR target/57819
	* simplify-rtx.c (simplify_unary_operation_1) <case ZERO_EXTEND>:
	Simplify (zero_extend:SI (subreg:QI (and:SI (reg:SI)
	(const_int 63)) 0)).
	* combine.c (make_extraction): Create ZERO_EXTEND or SIGN_EXTEND
	using simplify_gen_unary instead of gen_rtx_*_EXTEND.
	* config/i386/i386.md (*jcc_bt<mode>_1): New define_insn_and_split.

	* gcc.target/i386/pr57819.c: New test.

From-SVN: r200775