similar to: [newbie] trouble with global variables and CreateLoad/Store in JIT

Since the getelementptrs were implicitly generated by the CreateStore/Load I'm not sure how to get access to them. So I hacked the assignment to be done thrice: once using a manual decomposition into two GEPs and stores, once using the "big" CreateStore, once via the setGlobal function, printing addresses and memory contents at each point to the degree that I have access to them.

On Mon, Jun 5, 2017 at 1:34 PM, Nikodemus Siivola < nikodemus at random-state.net> wrote: > Uh. Turns out that if I hide the pointer to @foo from LLVM by passing it > through an opaque identity function ... then everything works fine. > > Is this a bug in LLVM or is there some magic involving globals I'm > misunderstanding? > This looks like a bug in the handling of

That's useful to know that the static compilation code path works. Furthermore, as expected from that: 52: c7 05 04 00 00 00 d5 00 00 00 movl $213, 4 00000054: IMAGE_REL_I386_DIR32 _foo It looks like the offset `4` of the second field of your struct is correct in the object file, so this does seem to be a problem in the JIT-specific linking/loading.

My code was hinky, but only in the sense that I was accidentally duplicating the definition variable in the module where the function was. With only the declaration in the second module loading the bitcode reproduces the issue. Managed an lli reproduction: $ cat jit-0.ll target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32" target triple =

I sent a long message yesterday describing a problem I thought had to do with the JIT stubs. After further investigating, the problem seems to be in the code generation. The following basic block seems to have an error in it's code generation: __exp.exit: ; preds = %codeRepl258, %__exp_bb_bb.exit phi double [ 1.000000e+00, %codeRepl258 ], [ %.reload.reload.i,

Hi all, I changed the code that checks whether a tail call is really eligible for optimization so that it performs the check/fix in SelectionDAGISel.cpp:BuildSelectionDAG() as suggest by Evan. Also eliminated an error that caused the remaining failing test cases in the test-suite. The results look very nice (on darwin x86, r42486). The same number (46) of failing test cases on patched

On Tue, 25 Sep 2007, Evan Cheng wrote: >> the stack adjustment only fastcc was not one of them. Now that fastcc >> can cause tail call optimization i had to change the convention from >> caller pops arguments to callee pops arguments in order to allow tail >> call optimization in a general way. > > Hmmm. Ok. So this is due to X86CallingConv.td changes? Unfortunately

Hello, The function ARMBaseInstrInfo::AnalyzeBranch contains the following piece of code: } else if (I->isReturn()) { // Returns can't be analyzed, but we should run cleanup. CantAnalyze = !isPredicated(I); } else { This could lead to cases where for a block that ends with a conditional return, AnalyzeBranch returns false (i.e. analyzed), both TBB and FBB are

Hello, I have written a pass that works nicely if I use it with the opt tool, as proposed by the "Writing an LLVM Pass" tutorial. Now I want to execute this pass directly when clang is executed. I use the technique described here: http://homes.cs.washington.edu/~asampson/blog/clangpass.html. The pass is loaded and executed, when I run clang with the right command line. But clang

Hi All, we have an issue with our LLVM-based JIT compiler - executing the compiled code corrupts memory (and subsequently crashes) if we alloca more than 4k of variables (more than 511 8-byte ints). The same code works on Windows 7 (32 and 64 bit), Linux, MacOS. We compile LLVM and our program with Microsoft's Visual Studio 2010. Both debug and release builds are affected. The variables

Using the LLVM C++ API, if I want to create an array via an Alloca instruction like: Value *a = ir_builder.CreateAlloca( my_type, my_size ); and then I want to initialize each element of the array with values computed elsewhere like: for ( vector<Value*>::const_iterator i = v.begin(); i != v.end(); ++i ) { builder.CreateStore( *i, a ); // How do I increment 'a' to point to

Hello, I have an optimisation issue in an llvm IR pass - the issue being that unnecessary instructions are generated in the final assembly (with -O3). I want to create the following assembly snippet: mov dl,BYTE PTR [rsi+rdi*1] add dl,0x1 adc dl,0x0 mov BYTE PTR [rsi+rdi*1],dl however what is created is (variant #1): mov dl,BYTE PTR [rsi+rdx*1] add dl,0x1 cmp

Hi Craig, On 03.07.19 17:33, Craig Topper wrote: > Don't the CreateICmp calls return a Value* with an i1 type? But then > they are added to an i8 type? Not sure that works.  I had that initially: auto cf = IRB.CreateICmpULT(Incr, ConstantInt::get(Int8Ty, 1)); auto carry = IRB.CreateZExt(cf, Int8Ty); Incr = IRB.CreateAdd(Incr, carry); it makes no difference to the generated assembly

I don't think it's the same problem as you described. By printing I meant calling printf function and passing my global variable as one of the arguments. My code: Instruction* InstructionVisitor::incrementGlobalKey(Instruction* I) { IRBuilder<> Builder(I->getContext()); Builder.SetInsertPoint(I->getNextNode()); GlobalVariable* key =

Hi all, I have this problem: I'm using LLVM's C++ API, mostly `IRBuilder<>` to generate code. Some of the generated code is just storing constant data to a location provided as a function argument. Something like `ir_builder.CreateStore(get_default_data(), ptrValue)` where `get_default_data()` may return a `ConstantArray` of `i8` and `ptrValue` is a function argument. Looking

Hi, I've been writing some optimization passes for LLVM and had good luck with the simple stuff, but I am running into all kinds of trouble trying to make copies of variables within a BasicBlock as part of a LoopPass I am trying to make copies of the variables that are in scope in the loop body like so: //Remove the existing terminator

Hi Everyone, I'm quite new to LLVM and I want to update value of global variable in LLVM IR. I created new global variable in ModulePass: bool runOnModule(llvm::Module &M) { IRBuilder<> Builder(M.getContext()); Instruction *I = &*inst_begin(M.getFunction("main")); Builder.SetInsertPoint(I); M.getOrInsertGlobal("globalKey",

We tested on 3.4.2 and 3.5.1. Later versions are slightly problematic to test since they don't compile with VS2010. Do you happen to know if it's fixed in one of the released versions, or if there is a workaround (chkstk?) or a bug report online? Thanks! Eph On 30.06.2015 12:58, Nicholas Chapman wrote: > It's a known issue. I believe it's fixed in trunk however. >

On Tue, May 20, 2008 at 5:03 AM, Nicolas Capens <nicolas at capens.net> wrote: > LoadInst *x = new LoadInst(ptr_x, "", false, basicBlock); > > // y = rcpps(x) // FIXME > StoreInst *storeResult = new StoreInst(y, ptr_y, false, basicBlock); Using an IRBuilder, something like the following (uncompiled, but it's at least approximately right): Value* x =

Hello all, I would like to create a new StoreInst into a basic block. I found that I could use methods like ConstantInt::get() to provide the Value* for the first argument of the constructor of the StoreInst, but I don't know how to provide the second one. For example, if I would to do x = 1, I would like to create the "Value" object of "x" for the second argument. I