re PR tree-optimization/46077 (ICE in tree vectorization when compiling towns_audio.cpp from scummvm)

	PR tree-optimization/46077
	* tree-chrec.c (eq_evolutions_p): Accept some expressions.

testsuite/
	PR tree-optimization/46077
	* gcc.dg/vect/O3-pr46077.c: New testcase.

From-SVN: r166958