PR tree-optimization/56541

	PR tree-optimization/56541
	* doc/invoke.texi (@item max-tree-if-conversion-phi-args): New item.
	* params.def (PARAM_MAX_TREE_IF_CONVERSION_PHI_ARGS): new param.
	* tree-if-conv.c (MAX_PHI_ARG_NUM): new macro.
	(any_complicated_phi): new static variable.
	(aggressive_if_conv): delete.
	(if_convertible_phi_p): support phis with more than two arguments.
	(if_convertible_bb_p): remvoe check on aggressive_if_conv and
	critical pred edges.
	(ifcvt_split_critical_edges): support phis with more than two
	arguments by checking new parameter.  only split critical edges
	if needed.
	(tree_if_conversion): handle simd pragma marked loop using new
	local variable aggressive_if_conv.  check any_complicated_phi.

	gcc/testsuite
	PR tree-optimization/56541
	* gcc.dg/tree-ssa/ifc-pr56541.c: new test.
	* gcc.dg/vect/pr56541.c: new test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@235808 138bc75d-0d04-0410-961f-82ee72b054a4