similar to: Efficient way to identify an instruction

Hi Tim, as always thanks for your help. Unfortunately I made a mistake in my email but apart from that I still have problems. Il giorno sab 27 lug 2019 alle ore 11:53 Tim Northover < t.p.northover at gmail.com> ha scritto: > Hi Alberto, > > On Sat, 27 Jul 2019 at 10:09, Alberto Barbaro via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > Having the reference I to

Hi Alberto, I have not used this myself, but I think you should be able to visit your Instruction ‘users()’. I think the name this function was given is a bit confusing, but this returns an iterator range you can iterate through to find instructions that depend on a given one. Similarly, you have the function ‘uses()’ that can be used to traverse down the DAG when instructions are still on SSA

---Adding llvm-dev list to CC--- Hi Alberto, Thanks for your prompt reply. Actually, I need this information(about total allocation size and object structure) on runtime, so that is why I was planning to encode this info and store it in the memory itself. Regards, Udit On Mon, Jan 27, 2020 at 7:05 PM Alberto Barbaro <barbaro.alberto at gmail.com> wrote: > Hello Udit, > I'm not

Thanks Tim, I'll try to solve my problem ASAP, if I cannot maybe I'll some other clarifications. Thanks again On Sat, Mar 9, 2019, 06:03 Tim Northover <t.p.northover at gmail.com> wrote: > Hi Alberto, > > On Sat, 9 Mar 2019 at 05:50, Alberto Barbaro via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > i8* getelementptr inbounds ([7 x i8], [7 x i8]*

Hi all, I have a global array declared as: table = internal constant [8 x [256 x i32]] ... At the moment I'm able to get the reference to table using Constant* g_var = cast<GlobalVariable>(I.getOperand(0))->getInitializer(); ( please consider I to be a GetElementPtrInst object ). Now I would like to understand how to get the address of table[2][3], for instance, considering that I

Hi all, I'm trying to print to screen the value read by the fread function. I'm at the point where source refers to the GetElementPtrInst ( pointer to the buffer where fread stored the data - %5 in my case ) and the fread() has been already called. I thought the correct approach to achieve what I need was: ExecutionContext& SF = ECStack.back(); GenericValue SRC =

David, sorry for this email but I noticed I made a mistake in the previous one. So I managed to compile llvm Debug with asserts release. I have used the following commands: cmake -DLLVM_TARGETS_TO_BUILD=X86 -DLLVM_ENABLE_RTTI=ON -DLLVM_ENABLE_FFI=ON -DCMAKE_BUILD_TYPE=Debug -DLLVM_ENABLE_ASSERTIONS=ON .. cmake --build . -- -j8 && sudo cmake --build . --target install Once lli was

> > Hey Lang - does any of this look familiar to you? I'm afraid not: I know nothing about the interpreter. As far as I'm aware it's essentially abandonware. Alberto: The usual recommendation in these circumstances is to use a JIT class instead of the interpreter. You're using -force-interpreter though, so I assume you really want to use the interpreter for your use case?

Hi Eric, Currently I'm mainly playing with interpreter and trying to understand how it exactly works. I have noticed that lli complains when llvm.dbg.value is encounter that why I wanted to remove it. Additionally, I would like to understand that performances with and without intrinsics and the impact they have on the interpreter in general. Thanks Alberto On Wed, Dec 18, 2019, 00:33 Eric

Hi David, In pretty sure that the crash is due to the instruction I have shared in my first email. In order to run pngpixel you just need libpng and zlib.. honest I thought that the .bc had Al the necessary. I'm happy to help you to reproduce it. As a curiosity, why do you think you cannot reproduce it? Unfortunately I won't be able to modify the interpreter soon.. anyway, I'll try to

Hi, I my case I needed to trace the execution of a specific .ll file. I wanted to know when a store and load instruction were executed. Maybe extending the Interpreter class was not the best option so I'm happy to hear suggestions. As a curiosity, why do you think that class should be rewritten? Thanks On Mon, Mar 4, 2019, 08:15 mayuyu.io <admin at mayuyu.io> wrote: > I dont quite

Hi David, My question is: why both #ifdef and #else branches are missing? I think at least one of the two should be present... In fact there is a case where the width could be greater then PNG_USER_WIDTH_MAX but not greater then PNG_UINT_31_MAX. That's why I was expecting at least one of the two... Thanks Alberto On Wed, Dec 18, 2019, 22:12 David Blaikie <dblaikie at gmail.com>

Hi all, I'm still working on the Interpreter class and I would like to understand why an operand cannot be cast to GetElementPtrInst. My code is something like: void MyInterpreter::visitCallInst(CallInst& I) { for(int i = 0; i < I.getNumArgOperands(); i++) { operand = I.getOperand(i); if(GetElementPtrInst* CI = dyn_cast<GetElementPtrInst>(operand)) {

Hi David, Thanks for your answer. Just to clarify, I would like to create 2 3 instructions put them in a function and execute them. Do you still think the JIT would be the best option? Thanks On Sun, Nov 18, 2018, 12:55 David Blaikie <dblaikie at gmail.com wrote: > If you're looking to execute code at runtime (within th eam process - or > across a network etc - as the one that

Hi David, Thanks for your email. I'm just trying to perform some basic analysis on the IR. For instance, is it possible to understand if the variable %10 depends on the value of the first parameter? I know that the first parameter can be referenced as %0 but a proper name would increase the readability. It is not so crucial for me atm. Thanks Alberto On Mon, Dec 9, 2019, 11:01 David Chisnall

Hi Tim, Thank you very much for the message. It indeed solved the problem. Thanks On Fri, Nov 8, 2019, 15:05 Tim Northover <t.p.northover at gmail.com> wrote: > Hi Alberto, > > On Fri, 8 Nov 2019 at 06:59, Alberto Barbaro via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > Is there any way for avoiding to use llvm.dbg.value within a bc file? > >

Hi Tim, My bad, I have installed a newer version of clang and all worked. Thanks On Sun, Dec 8, 2019, 10:05 Tim Northover <t.p.northover at gmail.com> wrote: > On Sun, 8 Dec 2019 at 09:54, Alberto Barbaro via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > thanks for your answer. Unfortunately I'm still using llvm 6.0 and in > llvm-dis I don't see that

Hi all, I have an Instruction object I from where I can correctly obtain the parent doing I.getParent(). Now I would like to understand how to obtain the PHI Nodes in that block. Do you suggest to iterate all over the instructions since the PHI nodes are always at the beginning or should I use another approach? What the best way to iterate over the instructions in a block? Thanks Alberto

Hi, All good points and jokes in your email :) My final goal is the get the value of %8 at runtime. So considering the program is called argv I would like to execute something like ./argv 22 and get the value of argv[0]. Is it possible? So far I have the address where the parameter at position 0 in store but I'd like to read the value and print it. I hope it is clear now Thanks again On

Hi David, Thanks for the suggestions. I can definitely provide the example bc file and image ( please see the attachments ). For the debug + asserts I need a bit of more time. Anyway the full output of lli is: lli --force-interpreter examples/pngpixel_crash.bc 0 0 examples/mini.png png_ptr->width: 1 max_pixel_depth: 24 row_bytes: 28 Unknown constant pointer type! UNREACHABLE executed at