re PR tree-optimization/77309 (wrong code at -Os and above on x86_64-linux-gnu (in the 64-bit mode))

	PR rtl-optimization/77309
	* combine.c (make_compound_operation): Allow EQ for IN_CODE, and
	don't assume an equality comparison for plain COMPARE.
	(simplify_comparison): Pass a more accurate code to
	make_compound_operation.

testsuite/
	PR rtl-optimization/77309
	* gcc.dg/torture/pr77309.c: New test.

From-SVN: r241912