[llvm-dev] How to get the address of a global variable in LLVM?

Dipanjan Das via llvm-dev llvm-dev at lists.llvm.org
Fri Apr 28 14:38:27 PDT 2017

I am a little confused. Can anyone explain me in short? The definition of
`func` is as below:

   void func(int var_addr) {
printf("[instr]: Global variable at address 0x%x\n", var_addr);

I want to insert a call to `func` just before the store instruction with
the address `x` of global variable `g` as parameter.

On 28 April 2017 at 14:34, Tim Northover <t.p.northover at gmail.com> wrote:

> On 28 April 2017 at 14:32, Jonathan Roelofs via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
> > You need a load instruction since your function takes an i32, not an
> > i32*.... A global's value in llvm is its address, not the numeric data it
> > contains.
> I suspect he actually wants to make his function take an "i8*" and
> bitcast his pointer to that type before calling it. [*]
> Tim.
> [*] Keeping it as an i32/i64 and using ptrtoint instead of bitcast
> would also work, but be less portable and elegant.


Thanks & Regards,
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