re PR tree-optimization/52678 (internal compiler error: in vect_update_ivs_after_vectorizer, at tree-vect-loop-manip.c:1842)

2012-03-23  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/52678
	* tree-vectorizer.h (struct _stmt_vec_info): Add
	loop_phi_evolution_part member.
	(STMT_VINFO_LOOP_PHI_EVOLUTION_PART): New define.
	* tree-vect-loop.c (vect_analyze_scalar_cycles_1): Initialize
	STMT_VINFO_LOOP_PHI_EVOLUTION_PART.
	* tree-vect-loop-manip.c (vect_update_ivs_after_vectorizer):
	Use the cached evolution part and the PHI nodes value from
	the loop preheader edge instead of re-analyzing the evolution.

	* gfortran.dg/pr52678.f: New testcase.

From-SVN: r185734