llvm dev - Oct 2011 - [LLVMdev] replacing a global variable by a constant

hi
i want  replacing a global variable by a constant  value for erase
instruction. i had seen the code that as follows

for (llvm::GlobalVariable::use_iterator U = gv->use_begin(); U
!gv->use_end();--U ) {
    llvm::Instruction *I = llvm::cast<llvm::Instruction>(U);
    I->replaceAllUsesWith(constPtr);
    I->eraseFromParent();
}

but i dont know how can declare constptr.
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Hi nada,
> i want  replacing a global variable by a constant  value for erase
instruction.
I'm not sure what you mean exactly.  A GlobalVariable has pointer type.  Do
you
want to replace that pointer by a constant pointer?  Or is it rather that you
want to say that the contents of the memory pointed to by the GlobalVariable is
constant, and have all places that load that GlobalVariable use the constant
instead?

Ciao, Duncan.
> i had seen the code that as follows
>
> for (llvm::GlobalVariable::use_iterator U = gv->use_begin(); U !=
gv->use_end();--U ) {
>      llvm::Instruction *I = llvm::cast<llvm::Instruction>(U);
>      I->replaceAllUsesWith(constPtr);
>      I->eraseFromParent();
> }
>
> but i dont know how can declare constptr.
>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

I would delete the Loop. I used the following code.

    cout << "begin to delete loop" << endl;
    for (Loop::block_iterator bi = L->block_begin(), bi2; bi
!L->block_end(); bi = bi2) {
        bi2 = bi;
        bi2++;
        BasicBlock * BB = *bi;
        for (BasicBlock::iterator ii = BB->begin(), ii2; ii != BB->end();
ii= ii2) {
            ii2 = ii;
            ii2++;
            Instruction *inst = ii;
            inst->eraseFromParent();
        }
        BB->eraseFromParent();
    }

But I get the following error:

Use still stuck around after Def is destroyed:  %t1 = icmp sle i32 %t0, 9
opt: /home/llvm/src/lib/VMCore/Value.cpp:75: virtual llvm::Value::~Value():
Assertion `use_empty() && "Uses remain when a value is
destroyed!"' failed.
0  opt 0x0848e569
Stack dump:


What suggestions do you have for solve this problem?
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