PR tree-optimization/65170
	* wide-int.cc (wi::mul_internal): For the umul_ppmm optimization,
	if val[1] < 0, clear also val[2] and return 3.

	* gcc.c-torture/execute/pr65170.c: New test.
	* gcc.dg/tree-ssa/vrp96.c: New test.

From-SVN: r220931