similar to: [LLVMdev] Basic Block Predecessor

Hi! I want to know How to count the number of predecessors for each basic block? Thank You ____________________________________________________________________________________ Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs

On Feb 1, 2011, at 1:34 PM, Andrew Trick wrote: > On Feb 1, 2011, at 1:08 PM, Andrew Clinton wrote: > >> I have a (non-entry) basic block that contains only PHI nodes and an >> unconditional branch (that does not branch to itself). Is it always >> possible to merge this block with it's successor and produce a >> semantically equivalent program? I'm

Hi all, Is there a way to walk through ALL the predecessors of a basic block in a CFG. I tried to iterate over the preds using this method for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++I) { BasicBlock *PredBB = *PI; } but this only gives the immediate predecessors for a basic block. For example, in this sample control flow graph. entry -> bb1 -> bb2 -> bb4

Hi I have checked all blocks, each block have a Terminator instruction and each blocks belongs to a function. I'm really confused. I guess the problem is caused by the removal of the Loop,The code is as follows: * //every block to header (except the ones in the loop), will now redirect to newblock for (pred_iterator PI = pred_begin(header); PI != pred_end(header); ++PI) {

Here's what I've got so far - it seems to work, aside from the fact that DeleteDeadPHIs is not removing at least one dead PHI in my test program. --------------------- static bool mergeBlockIntoSuccessor(BasicBlock *pred, BasicBlock *succ) { if (succ == pred) return false; if (pred->getFirstNonPHI() != pred->getTerminator()) return false; //

hi, how to get the number of immediate predecessors for each basic block (arguements of remarks statement at the beginning of the basic block) thank you aditya ____________________________________________________________________________________ Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs

How can I get list of its predecessor basic blocks from a basic block? --Rajwinder Singh -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20100625/21c52063/attachment.html>

Hi, All I want to implement DSWP Which is used for parallelization of loops. For this purpose, the loop was replaced with a new basic block in main function. And new functions were created and basic blocks of Loop assigned to them.I have checked blocks and branches for Succ and Pred relation and I have not found any problems. However I get the following error: * **opt:

Hi, while reading the TailDuplication pass, I found a check that looks rather pointless. TailDuplication looks at an unconditional branch instruction, BI. It performs a number of checks on the successor of this branch instruction, Dest. One of this checks is counting the number of predecessor. If this count is zero, Dest is regarded as dead and no tail duplication happens. However, as far as I

Hi Pabhat, Have you checked out DepthFirstIterator? (include/llvm/ADT/ DepthFirstIterator.h). It provides an iterator abstraction to perform a forward/reverse DFS traversal of a graph. Many of the LLVM datatypes that represent graphs have a template specialization of the GraphTraits<> class which allows separate algorithms to treat them as graphs, walk them, etc. (Both BasicBlock

Hello, I was investigating GVN.cpp file and I found suspicious part: 1587 bool NeedToSplitEdges = false; 1588 for (pred_iterator PI = pred_begin(LoadBB), E = pred_end(LoadBB); 1589 PI != E; ++PI) { 1590 BasicBlock *Pred = *PI; 1591 if (IsValueFullyAvailableInBlock(Pred, FullyAvailableBlocks)) { 1592 continue; 1593 } 1594 PredLoads[Pred] = 0; 1595 1596 if

Hey all, I have a piece of code (written in LLVM 2.8) which uses profiling results produced by ProfileInfo. It essentially computes the number of iterations performed by a loop from the profiling information available. The code snippet in my pass looks something like this. BasicBlock *header = loop->getHeader(); ProfileInfo &pi = getAnalysis< ProfileInfo >(); for(pred_iterator

Hi, Well, yes i did try your suggestion but i keep on running into a compilation problem. The error is: llvm[0]: Compiling Hello.cpp for Release build (PIC) /home/saraswat/llvm/llvm-2.1/include/llvm/ADT/GraphTraits.h: In instantiation of `llvm::GraphTraits<llvm::ilist_iterator<llvm::BasicBlock> >': Hello.cpp:59: instantiated from here

Thank you so much for your response. On Wed, Aug 15, 2018 at 3:08 PM, Xinliang David Li <xinliangli at gmail.com> wrote: > > > On Wed, Aug 15, 2018 at 7:36 AM Malhar Thakkar via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> Hey all, >> >> I have a piece of code (written in LLVM 2.8) which uses profiling results >> produced by ProfileInfo.

Dear All I'm making a transformation pass that inserts a new basic block at the start of a loop. However when I try to change predecessor/successor relations, it does not consider the new block in the loop at all. So I got that just inserting a loop in a function before another loop is not enough. So how exactly to do this job? Regards, Marwa Yusuf Teaching Assistant - Computer Engineering

On Wed, Aug 15, 2018 at 1:28 PM Xinliang David Li <xinliangli at gmail.com> wrote: > > > On Wed, Aug 15, 2018 at 12:46 PM Malhar Thakkar <cs13b1031 at iith.ac.in> > wrote: > >> Thank you so much for your response. >> >> On Wed, Aug 15, 2018 at 3:08 PM, Xinliang David Li <xinliangli at gmail.com> >> wrote: >> >>> >>>

I have a pointer to a basic block and am iterating thru its predecessor blocks. I want to get a pointer to the predecessor block. How do I do it. I am using following code and it given compile time errors. error: cannot convert 'llvm::const_pred_iterator' to 'const llvm::BasicBlock*' in initialization const BasicBlock *b = PH->getParent(); // process all pred block

Sorry, still a bit confused. Say we have two basic blocks: A and B. B has a label. There is no branch/control flow instructions explicit uses B. like this: A: code sequence does not contain br/other control flow instruction B: lable_of_b: code sequence Is A still a predecessor of B? Thanks. Chris Lattner wrote: > On Thu, 13 Jan 2005, Zhou Feng wrote: > >> hi, >> I'm

Today, the IR requires that if you have multiple edges from A to B (typically with a switch) any phi nodes in B must have an equal number of entries for A, but that all of them must have the same value. This seems rather annoying.... 1) It creates multiple uses of values in A for no apparently good reason 2) It makes updating PHI nodes using sets of predecessors incredibly hard 3) There is no

Hi, I want to instrument every control-flow edge in a CFG. What is the best way to do this ? I was thinking of getting a reference to the CFG using GraphTraits<Function *>. Is there a simple way to get the CFG handle? Thanks.