gcc man page says: max-cse-insns: The maximum instructions CSE process before flushing. The default is 1000. but gcc --param max-cse-insns=1000 gives the following error: cc1: error: invalid parameter 'max-cse-insns' With some googling I found the following patch which seems to have a bug where it uses the parameter max-flow-memory-locations erronously also in place for max-cse-insns http://gcc.gnu.org/ml/gcc-patches/2005-11/msg00249.html
Confirmed, this is a regression as the documentation is wrong but was correct before 4.1.0.
Subject: Bug number PR26685 A patch for this bug has been added to the patch tracker. The mailing list url for the patch is http://gcc.gnu.org/ml/gcc-patches/2006-04/msg01035.html
Subject: Bug 26685 Author: rguenth Date: Thu Apr 27 14:24:15 2006 New Revision: 113299 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=113299 Log: 2006-04-27 Richard Guenther <rguenther@suse.de> PR rtl-optimization/26685 * params.def (PARAM_MAX_CSE_INSNS): Correct typo that named this one "max-flow-memory-locations". Modified: branches/gcc-4_1-branch/gcc/ChangeLog branches/gcc-4_1-branch/gcc/params.def
Subject: Bug 26685 Author: rguenth Date: Thu Apr 27 14:25:49 2006 New Revision: 113300 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=113300 Log: 2006-04-27 Richard Guenther <rguenther@suse.de> PR rtl-optimization/26685 * params.def (PARAM_MAX_CSE_INSNS): Correct typo that named this one "max-flow-memory-locations". Modified: trunk/gcc/ChangeLog trunk/gcc/params.def
Fixed.