[LLVMdev] replacing a global variable by a constant

[Ralf Karrenberg]

Hi,

I am trying to replace a global variable with a constant.
I did manage to do it, but somehow it appears to be fairly bruteforce by
just iterating over all functions/bblocks/instructions and filtering for
 those that load the variable and replacing the instruction with
Instruction::replaceAllUsesWith().
The more intuitive way of iterating over the uses of the variable did
not work out as I have to replace the whole instruction instead of just
the operand (as GlobalVariable::replaceAllUsesWith() does) in order to
prevent loading from the memory address of the constant instead of
loading the constant :p. Basically what seems to be missing is some
method that returns the parent-instruction of a Use.

Maybe I am even tackling the whole problem from the wrong side anyway?!

And another question:
Does an invokation of a JIT through runFunction() perform any
optimization(s) by itself? Is there a way to display the generated code?

Thank you in advance :).

Regards,
Ralf