Help debugging variational quantum algorithm example

[zachary-crockett]

Today, I was checking out @Shavi's variational quantum algorithm example post. I gathered the code in the PDF into one C++ file, and also downloaded the current version of dlib (ver. 19.24), and I submitted it as a job using qsub.

After about 18 minutes, the job finished unsuccessfully. It was job number 2285384 in case that's helpful to someone for internal debugging.

Before failing, the job generated output files source.ll, source_flattened.ll, and (much later) source_unrolled.ll_3. That last file is over 128 MB.

The error in the stderr file is:

/glob/development-tools/versions/intel-quantum-sdk/1.2.20230316/LLVM-10.0.0-Linux/bin/opt: /home/uUSERID/project_dir/source_unrolled.ll_3:324093:387: error: use of undefined value '%for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for4'

and the offending line in source_unrolled.ll_3 is:

  %inc.i.i.i.i10 = phi i32 [ 8, %for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i.preheader ], [ %inc.i.i.i.i, %for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for.body_crit_edge.i_crit_edge.i_crit_edge.i_crit_edge.i.for.body.for.body_crit_edge.i.for.body.for4 ]

 Can anyone offer tips on how to debug or fix? Thanks!

[KevinR_Intel]

Hi Zachary,

Thanks for reporting this. I reached out to you by PM.

[KevinR_Intel]

Thanks for sharing your source file with us. We’ll dig into this and provide a fully working recipe, complete with any build instructions and compilaton flags required.

[zachary-crockett]

No worries at all. I really appreciate the speedy help!

[KevinR_Intel]

I responded with a full workflow to your original question under the original post about TFD for later readers:  https://community.intel.com/t5/Intel-Quantum-SDK/How-would-I-use-the-Intel-Quantum-SDK-to-write-a-complete/m-p/1487079/highlight/true#M79