llvm dev - Jul 2010 - [LLVMdev] Is there a way to address an instruction?

Hi,

In the objdump for binary, there is always an address associated with an 
instruction.

In the bitcode file, is there a way to address an instruction? It does 
not have to be a single ID like objdump.

Thanks,
Guoliang

Hi Guoliang,
> In the objdump for binary, there is always an address associated with an
> instruction.
>
> In the bitcode file, is there a way to address an instruction? It does
> not have to be a single ID like objdump.
no, there is no way in general.  You can always start a new basic block
just before your instruction and take the address of that basic block.
However later optimizations may move your instruction out of the basic
block.  What do you want this for?

Ciao,

Duncan.

Hi,
>> In the objdump for binary, there is always an address associated with
an
>> instruction.
>> In the bitcode file, is there a way to address an instruction? It does
>> not have to be a single ID like objdump.
> no, there is no way in general.  You can always start a new basic block
> just before your instruction and take the address of that basic block.
> However later optimizations may move your instruction out of the basic
> block.  What do you want this for?
Suppose I magically know that some instruction need special attention 
after reviewing one .ll file. Then I have a tool will handle them. The 
problem is how should I name that instruction so that my tool can 
identify it?

One way I can think of is using a triplet: function_name, the number of 
iterations to go to the block, and finally the number of iterations to 
reach the instruction.

I also noticed some instructions have name associated. But I cannot find 
too much about instruction name. If this is the way to go, then I have 
concern that whether two instructions will have the same name, and also 
I noticed some instructions do not have names.

Thanks,
Guoliang