Post SSA, not tracking liveness

Project Infrastructure LLVM Dev List Archives
#1

With “-print-machineinstrs” I’m seeing this message

Machine code for function main: Post SSA, not tracking liveness”

But I see “”, and “”, info in the printout,

The question is, does “not tracking liveness” mean this info is invalid / out-of-date ???

If so, what do I do to ensure that it is valid ???

I ask because I’m writing a post-RA MachineFunctionPass that requires this info.

Or to put it another way,

If the info is invalid why are we printing it out ?

Otherwise if the info is valid what does “not tracking liveness” mean ?

–Peter Lawrence.

#2

Hi Peter,

With “-print-machineinstrs” I’m seeing this message

# Machine code for function main: Post SSA, not tracking liveness”

But I see “<kill>”, and “<dead>”, info in the printout,
The question is, does “not tracking liveness” mean this info is invalid / out-of-date ???

This specific info is valid no matter what (or it is a bug).

What this means is that the LiveIntervalAnalysis is not correct anymore (must be recomputed).

If so, what do I do to ensure that it is valid ???
I ask because I’m writing a post-RA MachineFunctionPass that requires this info.

What kind of information do you need specifically?

Cheers,
-Quentin