similar to: [LLVMdev] #uses

I think since we use the replaceAllUsesWith to replace all uses of old one, the old one should already be a instruction with # of uses equals 0. So it should be Ok to directly delete it. Can you let me know if there is anything wrong with simple deletion? Why can we create illegal LLVM? Thanks, xiaodong ---- Original message ---- >Date: Thu, 26 Sep 2002 10:50:00 -0500 >From: "Vikram

Finally lli and llvmgcc can work under my directory. I wrote the following simple program and compiled it using gcc and then run it without any problem. But when I tried to compile it using llvmgcc and lli, llvmgcc gave me the following error message which I cannot understand: xli3|csil-suna37|~/cs426|[181]% llvmgcc test.c -o test test.c: In function `init': test.c:10: warning: cast to

Sorry I got really overwhelmed by so many classes and member functions in LLVM. So would you please clarify some problems I have? 1. If I see this instruction in the function. %S.i = alloca %struct.SimpleStruct Suppose SimpleStruct is as following: struct.SimpleStruct = type { int, double } When I read the instruction, how can I know the type of simplstruct, should I use 'getType'

Hi, I've another question about getelementptr. So, in the twisted mind of my little pass, I have a statement like this: %reg228-mod = getelementptr %struct.SimpleStruct* %N.1, long 0 ; <%struct.SimpleStruct*> [#uses=2] I'm not sure of the semantics of %a = getelementptr %b, long 0. I want to think that it is some kind of weird identity (no-op), judging from the operand

Hi, I have a question about the modify of instruction: Say I want to modify %a = getelementptr %struct %S, long 0, ubyte 1 into %a.f0 = getelementptr int* %S.f0, long 0 There are 3 ways I can think of to implement, but I'm not sure what should I do. 1. I can use new GetElementPtr to create a new instruction and use ReplaceInstWithInst() function to replace the old one. 2. I can use new

On 5/3/11 4:08 PM, tarun agrawal wrote: > HI > > I know it is a very simple question not worth asking here but I am > really struggling pls help me out.. This is a question worth asking; it's just that not everyone can answer all the time. :) If all you want to do is to follow the SSA def-use chain within a single function, then this is very easy. All you have to do is use

Hi, I need to find out all the places where the value of a variable is being used. For this I have to implement reaching definitions(def-use chains). When I searched for its implementation I found Iterating over def-use & use-def chains <http://llvm.org/docs/ProgrammersManual.html#iterate_chains>. will this work for finding the places where a variable is reaching? I tried to use

Thanks John, I know how to iterate through def-use chains and I also have realized the need for an algorithm to do the work. But the algorithm I am able to figure out is not linear in time. It wold be a great help if someone suggest me a way to get all basic-block along all path between two instruction. On Wed, May 4, 2011 at 7:00 AM, John Criswell <criswell at illinois.edu> wrote: >

I have a question about GetElementPtr. Suppose I have an GetElementPtr Instruction GI: %reg = getelementptr %ST* %s, uint 1, ubyte 2, ubyte 1, uint 5, uint 13 I want to check if this is the reference of a component of a structure, how can I do that? Should I check which operand of this instruction is 'ubyte' type? How can I do that in code? should I use ubyte *a =

Hello All, What would be the best way to trace Value Dependency Chains in LLVM. Can I use some API to perform this? The use-def chain process mentioned at http://llvm.org/docs/ProgrammersManual.html#iterate_chains will just get the values (Operands) being used in the current Instruction. For getting the values operands in the particular instruction are influenced from I have to recursively call

Hello All, Is the use-define chain related API avaliable in LLVM? I want to get the information about the variables' value changes at different points in the program. Best wishes.

You are correct, ubyte 2 simply means 3rd element of the structure. This quantity is always constant (it specifies the field number), so we could have used any signed or unsigned integer type for it instead of ubyte. UByte means we are limited to at most 256 structure fields but it also makes the bytecode representation more compact. (To remove this restriction, we may migrate to UInt in the

Thanks for your response! But I want to determine wheter the specific variable's value has been changed between two usages of variable, and wheter the parameter's value is changed in a function. Like the reaching definition analysis, and ud chains. 2012/8/9 ��f�� (Wei-Ren Chen) <chenwj at iis.sinica.edu.tw>: > On Thu, Aug 09, 2012 at 11:16:15AM +0800, Jianfei Hu wrote: >>

Dear Tarun, It just occurred to me that this may or may not be what you are asking about. This only finds basic blocks along the def-use chain of an instruction; it does not find all basic blocks along all paths between two instructions. I don't know of an algorithm off-hand for the latter, but if you understand how to iterate over def-use chains and the control-flow graph, then

Also sprach xli3 at uiuc.edu: } Sorry I got really overwhelmed by so many classes and member } functions in LLVM. So would you please clarify some problems } I have? } } 1. If I see this instruction in the function. } } %S.i = alloca %struct.SimpleStruct } } Suppose SimpleStruct is as following: } struct.SimpleStruct = type { int, double } } } When I read the instruction, how can I know the

On Wed, 2006-02-15 at 04:29, anubham suresh wrote: > hi everyone, > here i have a question: > is there any chance in llvm intermediate > representation to compare whether a operand (ie a > value) is used as a user without iterating over all > the instructions in a basic block. > i will explain this with an example: > i=p+4; > j=i+p; > > in the above example i

On 8/4/11 1:53 PM, Manish Gupta wrote: > It would be great help if someone can point me to similar code in > Analysis or Transform, i.e. tracing value dependencies chains. If I understand correctly, given an instruction I, you want to find its operands o1 through oN, and then find the instructions (or LLVM values) that generate the values o1 through oN, and then find the instructions

On Thu, Aug 09, 2012 at 11:16:15AM +0800, Jianfei Hu wrote: > Hello All, > > Is the use-define chain related API avaliable in LLVM? I want > to get the information > about the variables' value changes at different points in the program. Is this [1] fit your need? HTH, chenwj [1] http://llvm.org/docs/ProgrammersManual.html#iterate_chains -- Wei-Ren Chen (陳韋任)

Hello, is there any documentation for LLVM codebase other than produced by doxygen? The reason I'm asking is that doxygen docs are (1) not very complete at the moment, as lot of classes don't even have a description (2) is generally not the best way to get high-level view of a big codebase. As an example, consider this code: %tmp.1 = setgt int %i, 0 br bool %tmp.1, label

It would be great help if someone can point me to similar code in Analysis or Transform, i.e. tracing value dependencies chains. Thanks, Manish On Wed, Aug 3, 2011 at 10:47 AM, Manish Gupta <manishg at cs.ucsd.edu> wrote: > Hello All, > > What would be the best way to trace Value Dependency Chains in LLVM. Can I > use some API to perform this? > > The use-def chain