re PR tree-optimization/69615 (0 to limit signed range checks don't always use unsign...

re PR tree-optimization/69615 (0 to limit signed range checks don't always use unsigned compare)

	PR tree-optimization/69615
	* tree-ssa-reassoc.c (optimize_range_tests_var_bound): If rhs2 is lhs
	of a cast from a same precision integral SSA_NAME in a bb dominated
	by first_bb, retry with rhs2 set to the rhs1 of the cast.  Don't emit
	cast to utype if rhs2 has already a compatible type.

	* gcc.dg/tree-ssa/pr69615.c: New test.

From-SVN: r261264