similar to: [LLVMdev] DominanceFrontier/PostDominanceFrontier for PRE

Hi, I'm not able to answer your question. I'm wondering if you can create your own if it is just your own hobby project, or a project that you don't have to commit to the main repository. Creating DominatorFrontier seems to be expensive. However, if you are using bit-vector to represent a basic-block-set, I guess it can be done in linear time in practice. Following is the

Is there a reason this is better than the modified algorithm created by Ferrante? It looks like yours has as bad a worst case time bound in reality. That is, the algorithm runs in O(sum of the size of all the dominance frontiers). http://www.cs.rice.edu/~keith/Embed/dom.pdf See figure 5. It will only touch nodes actually in the dominance frontier. This is what GCC uses. There are actually real

On Sun, Nov 3, 2013 at 1:02 AM, Daniel Berlin <dberlin at dberlin.org> wrote: > Is there a reason this is better than the modified algorithm created > by Ferrante? > It looks like yours has as bad a worst case time bound in reality. > That is, the algorithm runs in O(sum of the size of all the dominance > frontiers). > > http://www.cs.rice.edu/~keith/Embed/dom.pdf >

On Sun, Nov 3, 2013 at 1:02 AM, Daniel Berlin <dberlin at dberlin.org> wrote: > As for a "better" way to implement PRE, it depends on what algorithm > you want to use. If you just want to write a PRE pass, that's easy > enough without dominance frontiers. > I simply want to write a PRE pass to get a better understanding of the transformation. Any tips on where to

On Sun, Nov 3, 2013 at 9:19 AM, Christopher Wood <christopherwood07 at gmail.com> wrote: > On Sun, Nov 3, 2013 at 1:02 AM, Daniel Berlin <dberlin at dberlin.org> wrote: >> >> As for a "better" way to implement PRE, it depends on what algorithm >> you want to use. If you just want to write a PRE pass, that's easy >> enough without dominance

Hi Guys, I saw in the API that DominanceFrontier has been deprecated. Is this for real? I have read the computational issues but shouldn't that be left to the users of llvm? My concern is I am writing a Control Dependence module that uses Dominance-Frontier information. Getting rid of Dominance Frontiers will put me in a tight spot. George -------------- next part -------------- An HTML

Hi George, > I saw in the API that DominanceFrontier has been deprecated. Is this for real? > I have read the computational issues but shouldn't that be left to the users of > llvm? > My concern is I am writing a Control Dependence module that uses > Dominance-Frontier information. > Getting rid of Dominance Frontiers will put me in a tight spot. if the dominancefrontier

George Baah <georgebaah at gmail.com> writes: > Hi Guys, > > I saw in the API that DominanceFrontier has been deprecated. Is this > for real? > I have read the computational issues but shouldn't that be left to the > users of llvm? > My concern is I am writing a Control Dependence module that uses > Dominance-Frontier information. > Getting rid of Dominance

Thank you John. Actually the opt tool (from LLVM 3.2 version) can generate the needed graphs (with pass "-domfrontier"). But I just want to surely know is there some pass or builder which can be integrated somehow so it will be possible directly to generate CDG? -- View this message in context: http://llvm.1065342.n5.nabble.com/Control-Dependence-Graph-builder-tp56687p56689.html Sent

On Dec 23, 2011, at 1:35 PM, Preston Briggs wrote: > Reading the comments in Analysis/DominanceFrontier.h, I see a note that the structure is deprecated and we're not to use it for anything new. > > Has it been replaced with something equally useful, or shall I redo the calculation for myself, or ...? We're hoping to remove them, because they're inherently an N^2 data

Reading the comments in Analysis/DominanceFrontier.h, I see a note that the structure is deprecated and we're not to use it for anything new. Has it been replaced with something equally useful, or shall I redo the calculation for myself, or ...? Thanks, Preston -------------- next part -------------- An HTML attachment was scrubbed... URL:

On 4/12/13 3:19 PM, Arsen wrote: > Thank you John. > Actually the opt tool (from LLVM 3.2 version) can generate the needed graphs > (with pass "-domfrontier"). > But I just want to surely know is there some pass or builder which can be > integrated somehow so it will be possible directly to generate CDG? Yes and no. There's isn't a control dependence pass in LLVM

When analysing a function "fn", my FunctionPass needs some PostDominanceFrontier information of functions which are called by function "fn". getAnalysis<PostDominanceFrontier>() cannot give the information, because it only gives the PostDominanceFrontier information of "fn", not the PostDominanceFrontier information of functions called by "fn".

A while ago I reported a bug in the computation of the post-dominance frontier (PDF). I submitted it as http://llvm.org/bugs/show_bug.cgi?id=1069, and it is now marked as a duplicate of http://llvm.org/bugs/show_bug.cgi?id=1098, which is still an open bug. I needed the PDF to compute control dependencies for code on which I'm working. I was not familiar with the algorithm used in LLVM

On 07/13/2012 04:30 PM, Duncan Sands wrote: > Hi, > >> I found the -postdomfrontier pass in *llvm*.org/docs/Passes.html, but >> 'opt' does not accept it. I could not find the relevant codes in >> PostDominance.cpp in SVN trunk, but I found some relevant codes here >> http://opensource.apple.com/source/clang/clang-137/src/lib/Analysis/PostDominators.cpp.

Thanks very much for the quick response. I have read the text many times, but it was not very clear to me why checking the two conditions involving dominance frontiers is equivalent to proving the pair {entry, exit} defines a refined region. I was asking for an mathematical proof really. It sounds to me like there should be a theorem or two in the graph theory endorsing it. Or do you mean, the

Hi shadowkernel, > I searched the archives and found > http://llvm.1065342.n5.nabble.com/post-dominance-frontier-fix-td10221.html > http://llvm.1065342.n5.nabble.com/Is-there-a-control-dependence-graph-builder-td35919.html#a35921 > http://llvm.1065342.n5.nabble.com/post-dominance-frontier-td6783.html > > It seems none of them are relevant. Could you give me more hints about

Hello All, I am interested in Control Dependence Graph building using the CFG and Dominance Frontier provided by corresponding passes. Just wandering whether LLVM provides some kind of pass or builder which will generate the Control Dependence Graph? Thanks, Arsen -- View this message in context: http://llvm.1065342.n5.nabble.com/Control-Dependence-Graph-builder-tp56687.html Sent from the

Hi, I found the -postdomfrontier pass in *llvm*.org/docs/Passes.html, but 'opt' does not accept it. I could not find the relevant codes in PostDominance.cpp in SVN trunk, but I found some relevant codes here http://opensource.apple.com/source/clang/clang-137/src/lib/Analysis/PostDominators.cpp. I am wondering why this pass is removed and what should I do if I want the post

On Jan 6, 2012, at 5:08 PM, Chris Lattner wrote: >>> >>> It's very like SSA construction, but must make provision >>> testing anti dependences. I had planned to use dominance frontiers to >>> guide placement of phi nodes, as usual. >> >> Ok, in that case, please check out include/llvm/Transforms/Utils/SSAUpdater.h, >> which is the