Deterministic printing of IR values

[vaivaswatha]

Closes #4517

---

Note

Make IR value names deterministic in the printer and update tests, expectations, and round-trip checks to match the new stable naming scheme.

• IR Printer:
  • Deterministic value naming: switch default names from sequential v<idx> to stable v<slot_key> (v\d+v\d+), importing slotmap::Key.
• Optimizer Tests:
  • Adjust constant folding expectations (omit temp name in const lines) and fixed expected value names in assertions.
• Test Suite:
  • Update all IR filecheck regexes and snapshots to new value-name pattern.
  • Strengthen IR (de)serialization test to round-trip twice for stability.
  • Minor test regex tweaks (e.g., panic regex, mem2reg/serialize expectations).

^{Written by Cursor Bugbot for commit 5b4f77a. This will update automatically on new commits. Configure here.}

[cursor]

This is the final PR Bugbot will review for you during this billing cycle

Your free Bugbot reviews will reset on December 7

Details

Your team is on the Bugbot Free tier. On this plan, Bugbot will review limited PRs each billing cycle for each member of your team.

To receive Bugbot reviews on all of your PRs, visit the Cursor dashboard to activate Pro and start your 14-day free trial.