re PR middle-end/39157 (Code that compiles fine in 1GB of memory with 4.1.2 requires > 20GB in 4.2.* and higher)
PR middle-end/39157
* Makefile.in (loop-invariant.o): Depend on $(PARAMS_H).
* params.h (LOOP_INVARIANT_MAX_BBS_IN_LOOP): Define.
* params.def (loop-invariant-max-bbs-in-loop): New parameter.
* opts.c (decode_options): Set loop-invariant-max-bbs-in-loop
parameter to 1000 for -O1 by default.
* doc/invoke.texi (loop-invariant-max-bbs-in-loop): Document new
parameter.
* loop-invariant.c: Include params.h.
(move_loop_invariants): Don't call move_single_loop_invariants on
very large loops.