similar to: [LLVMdev] LLVM Assembly Language Question

No, sorry, I made some typos in my question. I meant to ask For the instructions generated by LLVM for one particular function, is it possible to have duplicated instructions? Thanks On Wed, 14 Dec 2011, Duncan Sands wrote: > Hi Jane, > >> Hi, are the assembly instructions generated by LLVM for each function (and >> not just for each BasicBlock) unique? Thanks. > >

Hi Jane, > Hi, are the assembly instructions generated by LLVM for each function (and > not just for each BasicBlock) unique? Thanks. are you asking if LLVM merges identical functions? It does not (it does have an optional IR level pass for doing this though). Ciao, Duncan.

On 14/12/11 17:29, Jane Ren wrote: > No, sorry, I made some typos in my question. I meant to ask > > For the instructions generated by LLVM for one particular function, is it > possible to have duplicated instructions? I'm not sure what you are asking. If you look at the assembler for all but the simplest function you will see the same assembler instructions occurring several

Hey everyone, So I have an LLVM pass that appears to run completely and work fine, and then it aborts at the very end. When exiting the final runOnFunction call, I get the following error / stack dump. I cannot figure out why this is happening for the life of me - does anyone have any ideas? I'm not trying to do any crazy deallocation or anything, it just seems like a normal pass to me.

Hi Griffin, did your pass create a data structure that holds values somehow, and forgot to delete it? Also, try running under valgrind in case this is due to a memory error of some kind. Ciao, Duncan. > So I have an LLVM pass that appears to run completely and work fine, and > then it aborts at the very end. When exiting the final runOnFunction call, > I get the following error /

Hi Jianfei Hu, the GVN pass does something like this in the logic around GVN::propagateEquality. If in your example it was if a == 2 // BasicBlock A then then it replaces all occurrences of a with 2 in BasicBlock A. For this it needs to understand which basic blocks can only be reached via this conditional edge "a == 2". Ciao, Duncan. > Hello All, > > I want to

Using Valgrind hasn't shown me anything terribly unusual. And I'm confused because its not even trying to delete a real instruction; deleting a void type with no name? That doesn't make any sense... Any other hints? I've seen a few posts in the past about this relating to some internal LLVM bugs... -Griffin On Thu, 12 Jan 2012 21:26:41 +0100, Duncan Sands <baldrick at

Hello All, I want to dertermine whether a basicblock is in a conditional branch. such as, //============================= if a > 2 // BasicBlock A then BasicBlock B endif BasicBlock C //============================= What I want to identify is BasicBlock B, which is in a condtional block. but C is not. In other words, I want to distinguish BasicBlocks that * must * be executed and that

Under what circumstances will a TerminatorInst will have multiple successors? The three methods: virtual BasicBlock *getSuccessorV(unsigned idx) const = 0; virtual unsigned getNumSuccessorsV() const = 0; virtual void setSuccessorV(unsigned idx, BasicBlock *B) = 0; are defined for the TerminatorInst class, but I cannot see why a terminator is allowed to go to different targets. Thanks,

Hi, LLVM provides basic graph traversal for its CFGs, but I need additional operations, such as iterating over the edges. I thought I would solve this problem using the Boost graph library. It should be relatively simple to walk an LLVM CFG and add the BasicBlock objects to a Boost graph declared as: typedef boost::directed_graph<llvm::BasicBlock> Graph; Once constructed, this

Hi Duncan, On 5/6/12 6:12 PM, Duncan Sands wrote: > Hi Ralf, > >> Is there a clean way to attach metadata nodes to Arguments and/or >> BasicBlocks? > > not at the moment. Feel free to work on adding this functionality! I am looking into that now. I decided to temporarily go for the following syntax for BasicBlock metadata (subject to discussion): entry:

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) {

I have ran under valgrind memcheck the process using libLLVM-2.9.so (rev.126022) and got several errors: ==24227== Invalid read of size 1 ==24227== at 0x40274C9: memcpy (mc_replace_strmem.c:497) ==24227== by 0x40D5B84: char* std::string::_S_construct<char const*>(char const*, char const*, std::allocator<char> const&, std::forward_iterator_tag) (in

PS: I works when I use Instruction* prev = current->getPrevNode(); But then I have runtime error Stack dump that is very frequent... On Mon, Dec 17, 2012 at 6:20 PM, John Criswell <criswell at illinois.edu>wrote: > On 12/17/12 10:34 AM, Alexandru Ionut Diaconescu wrote: > > Hello, > > I am a beginner of LLVM. I am trying to move among the instructions of a >

OK. About the error it’s a long story, so it’s probably better to pin some source code here. Below is a piece of code related to my problem, clipped from lib/Transforms/Utils/ValueMapper.cpp. I was wondering what “materialized” means here. Value *Mapper::mapBlockAddress(const BlockAddress &BA) { Function *F = cast<Function>(mapValue(BA.getFunction())); // F may not have

On May 7, 2012, at 7:21 AM, Ralf Karrenberg <Chareos at gmx.de> wrote: > Hi Duncan, > > On 5/6/12 6:12 PM, Duncan Sands wrote: >> Hi Ralf, >> >>> Is there a clean way to attach metadata nodes to Arguments and/or >>> BasicBlocks? >> >> not at the moment. Feel free to work on adding this functionality! > > I am looking into that

Hi there, I'm trying to get a list of predecessors of a BasicBlock. I'm using a code similar to that on here (http://llvm.org/docs/ProgrammersManual.html#iterate_preds), but it appears to be more nodes been iterating that it should. Now, when I print out the llvm IR, I get something like: […] while.body: ; preds = %7, %while.cond […] for a code that

If we were to implement the #unroll pragma, we would want to add metadata to loop headers. But, it's not a big deal since we can simply add this metadata to block terminators. -----Original Message----- From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On Behalf Of Dan Gohman Sent: Tuesday, May 08, 2012 00:58 To: Ralf Karrenberg Cc: llvmdev at cs.uiuc.edu List

It try to put all basicblock in a switch in a loop, like that for example: int main() { if(something) somethingelse: else another; } become: int main() { while(true) { switch(var) { case 0: if(something) var+=1; else: var+=2; break; case1:

I am getting a segmentation fault as soon as I touch the Basic block *b value defined as :  std::string getPHIAssigns(const PHINode *PH)  { const BasicBlock *b = PH->getParent();    errs() << b->size(); where as getPHIAssigns is being called from               for (BasicBlock::iterator ins=b->begin(), e3=b->end(); ins!=e3; ++ins, ++l) // get instructions