re PR middle-end/54146 (Very slow compile with attribute((flatten)))

re PR middle-end/54146 (Very slow compile with attribute((flatten)))

	PR middle-end/54146
	* tree-flow.h (compute_global_livein): Remove prototype.
	* tree-into-ssa.c (compute_global_livein): Remove function.
	* tree-ssa-loop-manip.c: Include gimple-pretty-print.h.
	(find_sibling_superloop): New function.
	(compute_live_loop_exits): New function.
	(add_exit_phis_edge): Rename to add_exit_phi.  Do not allow
	inserting a PHI in a block that is not a loop exit for VAR.
	Add dumping if TDF_DETAILS.
	(add_exit_phis_var): Rewrite.
	(add_exit_phis): Update.
	(get_loops_exits): Rewrite to return an array of per-loop exits
	rather than one bitmap with all loop exits.
	(find_uses_to_rename_bb): Ignore virtual PHI nodes.
	(rewrite_into_loop_closed_ssa): Update.

From-SVN: r190442