similar to: [LLVMdev] Changing pointer addresses in Transform pass

Larry, On Wed, Aug 11, 2010 at 4:55 PM, Larry Gritz <lg at larrygritz.com> wrote: > I have a whole slew of questions about optimization passes. Answers to any > or all would be extremely helpful: > > How important are doInitialization/doFinalization? Most of the passes do not use them. > I can't detect any difference if I use them or not. Say, if you are writing

Hi again, I come back to this issue with an example. It's a pass which does nothing but throw the 'Unable to schedule' error. namespace { struct MyPass : public FunctionPass { static char ID; // Pass identification, replacement for typeid MyPass() : FunctionPass(ID) { initializeMyPassPass(*PassRegistry::getPassRegistry()); } virtual void

Hello, I'm writing a pass that adds a function prototype to the module during doInitialization() and stores the pointer in a global variable. If I run opt with "-O1" or less, everything works fine. However, If I call opt with "-O2" or "-O3" then as soon as runOnFunction() is called, the pointer seems to be NULL. Here is a code that shows the problem:

Hello ! I have a toolchain of two passes. First one, is a transformation pass that should add metadata to some structures (instructions/variables) and the second pass is an analyzing pass which needs to access the added metadata. The problem is with my adding metadata transformation pass. There might be two problems(or both): First, maybe I don't add correctly metadata.

Hello everyone, I am trying to write a trivial adding metadata transformation pass. I have Test.bc the target on which I want to perform transformations. First, I compile with clang++ my target program and I have my resulting Test.bc. I save it under Test1.bc. As a particular example, I have " %myDimension = alloca %class.ThreeDimension, align 4 ". Second, I apply my pass :

This gives me: Assertion failed: (0 && "Unable to find on the fly pass"), function getOnTheFlyPass, file PassManager.cpp #include "llvm/Module.h" #include "llvm/Analysis/MemoryDependenceAnalysis.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; struct Hello: public FunctionPass { public: static char ID; Hello(): FunctionPass(ID) {

Hello LLVMdev, I’m using LLVM to do static analysis exclusively (without any code generation). To implement this analysis, I’m using multiple address spaces to disambiguate the purpose of the pointed memory. Since address spaces never alias in my model, I set on to implement an alias analysis pass that would exactly provide this information, as I’m seeing a couple of otherwise dead store that

I am currectly experimenting with -Xclang option.. I have a simple pass (to just print function names). I ran: clang -Xclang -load -Xclang LLVMHello.so t.c but nothing was printed, no output from the pass. when I run: opt -load LLVMHello.so -hello t.ll I get the output from pass (i.e. list of function names) Part of the source ode of the Hello pass: struct Hello : public FunctionPass {

I am having problems passing analysis results to transformation passes, so I reduced my testcase into the following bare bone: Pass1: simple FunctionPass, counting functions Pass2: transformation pass, for now, just trying to obtain a reference of Pass1 using AU.getAnalysis<Pass1>() inside its runOnFunction(). When I run it, I get the following runtime error: opt -load

On 6/15/11 6:46 PM, Alexey Bakhirkin wrote: > Hi. I'm trying to implement a module pass which can be dynamically > loaded by `opt` (against up-to-date llvm from svn). > Despite what the tutorial > (http://llvm.org/docs/WritingAnLLVMPass.html) states in my module pass > I cannot perform getAnalysis and fetch the function pass result. > When trying to do so `opt` fails with the

On Wed, 2004-11-17 at 23:19, Abhijit Ray wrote: > 1. If we run a few passes in a sequence ..is the bytecode file > transformed after each pass in sequence i.e > > if we have > a) opt -pass1 -pass2 -pass3 < in.bc > out.bc > b)opt -pass1 -pass2 < in.bc > tmp.bc > opt -pass3 < tmp.bc > out.bc > > are the above two equivalent ? Yes, they're

On Thu, 24 Jun 2004, Vladimir Prus wrote: > I wonder in what cases FunctionPass is better that Pass. For example, > addPassesToEmitAssembly takes PassManger and addPassesToJITCompile takes > FunctionPassManager. Here's a simple way to look at it. Use a Function pass whenever you can. A function pass will always work where a Pass works (it derives from pass as you've noticed),

Thanks, John. There were a couple of function declarations in the module, and 'getAnalysis' failed for those. By the way, what do you mean by "in older versions of LLVM"? I'm quite sure I was using the latest llvm trunk. 2011/6/16 John Criswell <criswell at cs.uiuc.edu>: > On 6/15/11 6:46 PM, Alexey Bakhirkin wrote: >> Hi. I'm trying to implement a module

Hi. I'm trying to implement a module pass which can be dynamically loaded by `opt` (against up-to-date llvm from svn). Despite what the tutorial (http://llvm.org/docs/WritingAnLLVMPass.html) states in my module pass I cannot perform getAnalysis and fetch the function pass result. When trying to do so `opt` fails with the following mesage: [***@*** ***]$ opt -load

Hello all; So my goal is to insert some (self-written) function calls in the LLVM IR. I can achieve it with a ModulePass and using the getOrInsertFunction() call. For a ModulePass I follow the steps- 1. Compile the code (in which call instructions are to be inserted) to LLVM IR 2. Compile the file (which contains the *called* external function ) to LLVM IR 3. Link them together and run the

I have written a new pass, it compiles ok but crashes when i run it with error (llvm::Pass::Pass(llvm::PassKind, intptr_t): Assertion `pid && "pid cannot be 0"' failed.). The pass is : using namespace llvm; namespace { struct Dfl : public FunctionPass { static char ID; Dfl() : FunctionPass(ID) { } virtual bool runOnFunction(Function &F) { bool

llvm/include/llvm/Pass.h:93: llvm::Pass::Pass(llvm::PassKind, intptr_t): Assertion `pid && "pid cannot be 0"' failed. On Mon, Jan 31, 2011 at 3:55 PM, Surinder <surifilms at gmail.com> wrote: > I have written a new pass, it compiles ok but crashes when i run it > with error (llvm::Pass::Pass(llvm::PassKind, intptr_t): Assertion `pid > && "pid

In runOnFunction(), you should check to see if the function F is a declaration before calling getAnalysis(F). Calling getAnalysis<FunctionPass>() on a function that is a declaration will trigger an assertion if the function is just a declaration. To see if a function is a declaration, call its isDeclaration() method (i.e. if (F->isDeclaration()) ... ) -- John T. On 10/13/11 8:09

I wonder in what cases FunctionPass is better that Pass. For example, addPassesToEmitAssembly takes PassManger and addPassesToJITCompile takes FunctionPassManager. Another question is about FunctionPassManager::run(Function&) and FunctionPass(Function&). The former calls the later, which is fine, but the latter looks like this: bool FunctionPass::run(Function &F) { if

Hi John!! >1) Have you ensured that your passes have different arguments to the = >RegisterPass constructor (i.e., they have different names)? Yes, I only write one Pass (Function Pass) and gave it that one name. >2) Are you sure that variable X is only being defined once? There are = >some ways in which you could have unintentionally defined it twice. For = >example, if you