Sahoo, Swarup Kumar
2012-Sep-13 15:18 UTC
[LLVMdev] Dominance frontier & Postdominance frontier
Hi, I found that LLVM 3.1 says Dominance frontier is deprecated. Can anyone please tell me, if there is any replacement for Dominance frontier & Postdominance frontier in LLVM? What are the options if we need to use them? Thanks, Swarup. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120913/e46bb309/attachment.html>
On 9/13/12 10:18 AM, Sahoo, Swarup Kumar wrote:> Hi, > > I found that LLVM 3.1 says Dominance frontier is deprecated. Can > anyone please tell me, if there is any replacement for Dominance > frontier & Postdominance frontier in LLVM? What are the options if we > need to use them?You may want to read this thread on llvmdev from August: http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-August/052682.html Marco's reply mentions an alternative algorithm in Muchnick's compiler book. I believe the algorithm in Section 7.3 of Allen and Kennedy uses the post dominator tree only. -- John T.> > Thanks, > Swarup. > > > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120913/46ba88c9/attachment.html>
You can easily calculate the DF(x) of a node if you have the J-edges. Look at V Sreedhar's classic thesis on DJ graphs. Look at our work in TOPLAS 2005 for computing DF and phi using DJ graphs. Its pretty straightforward if u hv the dom tree and J-edges. J-edges are nothing else but CFG edges which are not present in the dominator tree. Hope this helps. Post-dom-frontier is an analogous problem on the reverse cfg and pdom tree. - Dibyendu From: Sahoo, Swarup Kumar [mailto:ssahoo2 at illinois.edu] Sent: Thursday, September 13, 2012 10:18 AM To: llvmdev at cs.uiuc.edu <llvmdev at cs.uiuc.edu> Subject: [LLVMdev] Dominance frontier & Postdominance frontier Hi, I found that LLVM 3.1 says Dominance frontier is deprecated. Can anyone please tell me, if there is any replacement for Dominance frontier & Postdominance frontier in LLVM? What are the options if we need to use them? Thanks, Swarup. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120913/149e8b56/attachment.html>