criswell at uiuc.edu
Thu Jun 24 08:15:41 PDT 2010
RAJWINDER SINGH wrote:
> I am making a CDFG graph out of the instruction.
What is a CDFG? Do you mean a control dependence graph?
Control-dependence can be computed utilizing the PostDominatorTree pass.
> for that purpose I require the name because
> if I am using its ID then ID may be same for the two such variables.
What do you mean by an instruction's ID?
> How can I distinguish b/w them?
I'm assuming that you're writing an LLVM analysis pass that creates this
CDFG data structure as an internal, in-memory data structure. If that
is the case, then you simply use the pointer to the Instruction object
to identify it. Each Instruction object inhabits a different location
in memory; therefore, pointers to them are unique.
-- John T.
> --Rajwinder Singh
> On Thu, Jun 24, 2010 at 12:12 AM, John Criswell <criswell at uiuc.edu
> <mailto:criswell at uiuc.edu>> wrote:
> RAJWINDER SINGH wrote:
> Sir ,how can I get the variable %2 in instruction
> %2 = sub nsw i32 1, %y If I am using getName() function
> then it outputs the null string.
> How can I get the original name?
> I don't believe the instruction has a name. The LLVM disassembler
> just assigns a numeric name when generating the .ll file so that
> the output is readable by a human.
> What is it that you are trying to do that requires that name of an
> SSA value?
> -- John T.
> Rajwinder Singh
More information about the llvm-dev