re PR target/82580 (Optimize comparisons for __int128 on x86-64)

re PR target/82580 (Optimize comparisons for __int128 on x86-64)

	PR target/82580
	* config/i386/i386-modes.def (CCGZ): New CC mode.
	* config/i386/i386.md (sub<mode>3_carry_ccgz): New insn pattern.
	* config/i386/predicates.md (ix86_comparison_operator):
	Handle CCGZmode.
	* config/i386/i386.c (ix86_expand_branch) <case E_TImode>:
	Emulate LE, LEU, GT, GTU, LT, LTU, GE and GEU double-word comparisons
	with double-word subtraction.
	(put_condition_code): Handle CCGZmode.

testsuite/ChangeLog:

	PR target/82580
	* gcc.target/i386/pr82580.c: New test.

From-SVN: r253867