Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!snorkelwacker!spdcc!ima!esegue!compilers-sender From: rfg@ics.UCI.EDU (Ron Guilmette) Newsgroups: comp.compilers Subject: Re: Graph coloring, patents Message-ID: <1989Nov16.012226.4078@esegue.segue.boston.ma.us> Date: 16 Nov 89 01:22:26 GMT References: <1989Nov15.010209.11362@esegue.segue.boston.ma.us> Sender: compilers-sender@esegue.segue.boston.ma.us Reply-To: Ron Guilmette Organization: University of California, Irvine - Dept of ICS Lines: 17 Approved: compilers@esegue.segue.boston.ma.us In article <1989Nov15.010209.11362@esegue.segue.boston.ma.us> Preston Briggs writes: >I don't know which is more effective. I suspect (with no evidence) that >Chow's method will be better on constrained machines (not many registers) and >Chaitin's better otherwise. Neither seems worthwhile without some global >optimization to provide grist for the mill. Chow's method is always at least as good as Chaitin's graph coloring (and sometimes better). It is likely that it will only be significantly better on machines *without* lots of registers. That's because both of these methods try to avoid spills. If you have a zillion registers, you never spill with either method, so they're equal in that case. // rfg -- Send compilers articles to compilers@esegue.segue.boston.ma.us {spdcc | ima | lotus}!esegue. Meta-mail to compilers-request@esegue. Please send responses to the author of the message, not the poster.