✨ Map scf::WhileOps using the restore strategy

[MatthiasReumann]

Description

This pull request adds mapping support for the scf::WhileOp.

• ✨ Add scf::WhileOp to supported SCF ops in Mapping.cpp
• 🐛 Fix WireIterator for scf::WhileOp
• ♻️ Simplify isExecutable function in test_mapping.cpp
• ♻️ Simplify dispatch function in Mapping.cpp

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• I have added entries to the changelog for any noteworthy additions, changes, fixes, or removals.
• I have added migration instructions to the upgrade guide (if needed).
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the CI checks.
• I have reviewed my own code changes.

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[codecov]

Codecov Report

❌ Patch coverage is 98.37838% with 3 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...lir/lib/Dialect/QCO/Transforms/Mapping/Mapping.cpp	98.8%	2 Missing ⚠️
mlir/lib/Dialect/QCO/Utils/WireIterator.cpp	92.3%	1 Missing ⚠️

📢 Thoughts on this report? Let us know!

[MatthiasReumann]

@coderabbitai full review

[coderabbitai]

✅ Action performed

Full review finished.

[coderabbitai]

Caution

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✨ Finishing Touches

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch feat/scf-while-ops-mapping

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[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@mlir/unittests/Dialect/QCO/Transforms/Mapping/test_mapping.cpp`:
- Around line 107-127: Update the initialization in the mapping test around
initArgs, initialHardwareOrder, and localM so SCF hardware indices are derived
from qubit-only init operands, matching the filtered qubitArgs order. Filter
scf::WhileOp getInits() and scf::ForOp getInits() by QubitType before mapping
through m, while preserving qco::IfOp behavior and ensuring mixed-type loops do
not access missing DenseMap entries.
- Line 738: Add routing-relevant gates to the while after-region test around the
identity callback in the mapping test, so recursive after-region routing and
terminator realignment are exercised. Extend the test inputs and assertions to
verify the mapped values and control flow remain correctly aligned through the
after-region rather than merely returning args unchanged.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: ce75cc65-da3f-4bff-a384-61ca652f1b74

📥 Commits

Reviewing files that changed from the base of the PR and between 559fde4 and 0c05d8e.

📒 Files selected for processing (4)

• mlir/include/mlir/Dialect/QCO/Utils/Drivers.h
• mlir/lib/Dialect/QCO/Transforms/Mapping/Mapping.cpp
• mlir/lib/Dialect/QCO/Utils/WireIterator.cpp
• mlir/unittests/Dialect/QCO/Transforms/Mapping/test_mapping.cpp

[burgholzer]

I haven't scrutinized every single detail here, but this looks good except for the conflicts that need to be addressed. Afterwards, this can go in.